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White clover seed production in British Columbia Huxley, David Morton 1978

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WHITE CLOVER SEED PRODUCTION IN BRITISH COLUMBIA by DAVID MORTON HUXLEY B.Sc,  U n i v e r s i t y o f B r i t i s h Columbia, 1970  A THESIS SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF Master o f S c i e n c e in The F a c u l t y o f Graduate  Studies  Department o f P l a n t S c i e n c e (Faculty of A g r i c u l t u r a l Sciences) The U n i v e r s i t y o f B r i t i s h  Columbia  We accept t h i s t h e s i s as conforming t o the r e q u i r e d s t a n d a r d .  THE UNIVERSITY OF BRITISH COLUMBIA November 1978 (c) David Morton H u x l e y , 1978.  In p r e s e n t i n g  t h i s t h e s i s i n p a r t i a l f u l f i l m e n t o f the requirements f o r  an advanced degree a t t h e U n i v e r s i t y o f B r i t i s h Columbia, I agree t h a t the L i b r a r y s h a l l make i t f r e e l y  a v a i l a b l e f o r r e f e r e n c e and s t u d y .  I f u r t h e r agree t h a t p e r m i s s i o n f o r e x t e n s i v e  copying o f t h i s  thesis  f o r s c h o l a r l y purposes may be g r a n t e d by t h e Head o f my Department o r by h i s r e p r e s e n t a t i v e s .  I t i s understood that copying or p u b l i c a t i o n  of t h i s t h e s i s f o r f i n a n c i a l  g a i n s h a l l n o t be a l l o w e d w i t h o u t my  written permission.  D a v i d M. H u x l e y  Department o f P l a n t  Science  The U n i v e r s i t y o f B r i t i s h Columbia 2075 Wesbrook P l a c e Vancouver, Canada V6T 1W5  Date  ii ABSTRACT In t h e C r e s t o n v a l l e y i n s o u t h e a s t e r n B.C., i n t e r m e d i a t e w h i t e c l o v e r i s grown f o r seed and i s a u s e f u l c r o p i n farm f i e l d r o t a t i o n s .  For  s e v e r a l y e a r s seed y i e l d s have been d e c l i n i n g , and d e s p i t e good p r i c e s and markets,  hectarage to white c l o v e r i s d e c l i n i n g .  In 1976, work was i n i t i a t e d t o determine  some o f t h e f a c t o r s  i b l e f o r t h e d e c l i n e i n seed y i e l d and h e c t a r a g e . exploratory  respons-  A t the same t i m e , an  s t u d y o f t h e g e n e t i c v a r i a t i o n i n t h e seed s t o c k s o f t h e v a l l e y  was i n s t i t u t e d i n t h e hope t h a t a C r e s t o n s t r a i n might be c h a r a c t e r i z e d o r selected. In 1977, i n t h e C r e s t o n v a l l e y , a s e r i e s o f r e p l i c a t e d p l o t s i n s i x f i e l d s , representative  o f t h e e d a p h i c , c l i m a t i c and management regimes,  were e s t a b l i s h e d t o measure seed and f o r a g e y i e l d s and l o s s e s from m u l t i p l e sources.  A t t h e U n i v e r s i t y o f B.C., f o u r hundred i n d i v i d u a l p l a n t s r e p r e s e n t -  a t i v e o f twenty s o u r c e s , i n c l u d i n g some C r e s t o n s o u r c e s , and encompassing s u b s t a n t i a l g e n e t i c d i v e r s i t y , were e s t a b l i s h e d from seed i n r e p l i c a t e d uniform nurseries.  I n an a d j a c e n t n u r s e r y one hundred and e i g h t y  c l o n e s were e s t a b l i s h e d .  O b s e r v a t i o n and measurement o f a number o f c h a r -  a c t e r s were t a k e n on a l l p l a n t s s e v e r a l times d u r i n g t h e growing Average c l e a n seed y i e l d s on t h e C r e s t o n e x p e r i m e n t a l p l o t s from 468-972 kgs. p e r h e c t a r e (418-868 l b s p e r a c r e ) . c l e a n seed, by c o n t r a s t , ranged lbs  per a c r e ) .  Creston  season. ranged  Farm y i e l d s o f  from 262-491 kgs per h e c t a r e (240 t o 450  I t was e s t i m a t e d t h a t o f t h e l o s s i n seed t h r e s h e d  (dock-  age) , but not c l e a n e d , 3-10% was i n s e c t damaged; l o s s a t t r i b u t a b l e t o farm h a r v e s t i n g procedures was e s t i m a t e d t o r e a c h 50%. Losses i n t h e d e v e l o p i n g c r o p a r e d i f f i c u l t but appeared t o be v e r y s e r i o u s .  to assess q u a n t i t a t i v e l y  To o f f s e t t h e s e l o s s e s , i n r e c e n t y e a r s ,  iii  p r o d u c e r s have been r e d u c i n g t h e l e n g t h o f w h i t e c l o v e r l e y and a r e now most cases o b t a i n i n g one  seed c r o p o n l y i n t h e year a f t e r  in  establishment;  t h i s p r a c t i c e , i f c a r r i e d on w i t h o u t c o u n t e r s e l e c t i o n , might r e s u l t i n a biennial habit. Three s p e c i e s o f w e e v i l appeared t o be the most s e r i o u s p e s t s , v i z . the c l o v e r root c u r c u l i o  ( S i t o n a h i s p i d u l a F a b . ) , and the c l o v e r seed  weevil (Miccotrogus p i c i r o s t r i s (Hypera n i g r i r o s t r i s Fab.).  (F)) and t h e l e s s e r c l o v e r l e a f w e e v i l  The p o p u l a t i o n peaks o f t h e a d u l t s a p p a r e n t l y  o c c u r at d i f f e r e n t times i n the season.  C u r r e n t l y o n l y one a e r i a l  applica-  t i o n o f m a l a t h i o n i s a p p l i e d i n June t o c o n t r o l the c l o v e r seed w e e v i l . Almost a l l r o o t s examined bore s i g n s o f l a r v a l f e e d i n g , d o u b t l e s s due  to  the c l o v e r r o o t c u r c u l i o ; r o o t n o d u l e s , abundant i n s p r i n g , d i m i n i s h e d r a p i d l y as t h e season p r o g r e s s e d .  Measurements o f n i t r o g e n f i x a t i o n , u s i n g  t h e a c e t y l e n e r e d u c t i o n t e c h n i q u e and t h e K j e l d a h l N - d e t e r m i n a t i o n ,  were  incomplete. Flower f r e q u e n c y and development, f l o w e r c o l o u r , l e a f a r e a , p e t i o l e l e n g t h , l e a f markings,  p l a n t h e i g h t and w e i g h t , and p r u s s i c a c i d  were some o f t h e c h a r a c t e r s measured and observed  levels  on the i n d i v i d u a l p l a n t s ,  e s t a b l i s h e d i n the U.B.C. n u r s e r i e s from C r e s t o n and o t h e r s o u r c e s . unexpectedly,  the C r e s t o n s t o c k s possessed  Not  a measure o f d i s t i n c t i o n from  most o t h e r s t o c k s o f i n t e r m e d i a t e w h i t e c l o v e r ; n o n e t h e l e s s , t h e r e appeared t o be ample v a r i a b i l i t y i n the C r e s t o n s t o c k s w i t h i n which t o s e l e c t  strains  to meet a t l e a s t two needs o f the r e g i o n - v i z . a)  p l a n t s u s e f u l i n the r e v e g e t a t i o n o f ranges and o f u n s t a b l e  soils,  and b)  p l a n t s w e l l adapted t o t h e a r a b l e l o n g l e y p a s t u r e s o f t h e humid and sub-humid a r e a s .  iv  TABLE OF CONTENTS  INTRODUCTION REVIEW OF RELEVANT LITERATURE 2.1  G e n e r a l "biology o f w h i t e c l o v e r 2.1.1 2.1.2 2.1.3 2.1.4 2.1.5 2.1.6 2.1.7  Nomenclature Agronomic r a c e s Strains Seed A e r i a l development Reproductive structures Root systems  2.2  Biological nitrogen fixation  2.3  Marker g e n e t i c s 2.3.1 I n t r o d u c t i o n 2.3.2 Cyanogenesis 2.3.3 L e a f markings  2.4  Seed p r o d u c t i o n 2.4.1 2.4.2 2.h.3  G e n e r a l b i o l o g y and management P e s t s o f w h i t e c l o v e r seed c r o p s D i s e a s e s o f w h i t e c l o v e r seed crops  DESCRIPTION OF STUDY AREAS 3.1.1 3.1.2 3.1.3  Creston F i e l d management S o i l s e r i e s by f i e l d s  OBSERVATIONS AND EXPERIMENTS A. 4.1  For Creston Based*Studies Sampling f o r I n s e c t s 4.1.1  Sweeps 4.1.1.1 M a t e r i a l s and methods 4.1.1.2 O b s e r v a t i o n s and r e s u l t s 4.1.1.3 D i s c u s s i o n  V  4.1.2  Sticky traps it.1.2.1 M a t e r i a l s and methods 4.1.2.2 O b s e r v a t i o n s and r e s u l t s 4.1.2.3 D i s c u s s i o n  k.1.3  Pitfall 4.1.3.1 4.1.3.2 4.1.3.3  4.1.4  4.2  4.3  4.4  PAGE NO. 39 39 40 44  traps M a t e r i a l s and methods O b s e r v a t i o n s and r e s u l t s Discussion  S o i l i n s e c t sampling 4.1.4.1 M a t e r i a l s and methods 4.1.4.2 O b s e r v a t i o n s and methods 4.1.4.3 D i s c u s s i o n  4  4  4  4  4  4  4  8  4 8 4 4  8  9 51  S o i l Sampling f o r F e r t i l i t y  53  4.2.1 4.2.2 4.2.3  53 53 53  M a t e r i a l s and methods O b s e r v a t i o n s and r e s u l t s Discussion  Phytomass Sampling  54  4.3.1  F o r d r y m a t t e r y i e l d s on 30-5-77 4.3.1.1 M a t e r i a l s and methods 4.3.1.2 O b s e r v a t i o n s and r e s u l t s 4.3.1.3 D i s c u s s i o n  54 54 54 54  4.3.2  F o r d r y m a t t e r y i e l d s on 5-8-77 4.3.2.1 M a t e r i a l s and methods 4.3.2.2 O b s e r v a t i o n s and r e s u l t s 4.3.^2.3 D i s c u s s i o n  54 54 54 58  4.3.3  F o r seed 4.3.3.1 4.3.3.2 4.3.3.3  58 58 58 58  4.3.4  I n d i v i d u a l head e x a m i n a t i o n s 4.3.4.1 M a t e r i a l s and methods 4.3.4.2 O b s e r v a t i o n s and r e s u l t s 4.3.4.3 D i s c u s s i o n  and i n f l o r e s c e n c e y i e l d s on 5-8-77 M a t e r i a l s and methods O b s e r v a t i o n s and r e s u l t s Discussion  62 62 62 6  2  4.3.5  L e a f a r e a , p e t i o l e l e n g t h and p e d u n c l e l e n g t h 4.3.5.1 M a t e r i a l s and methods 4.3.5.2 O b s e r v a t i o n s and r e s u l t s 4.3.5-3 D i s c u s s i o n  62 62 65 65  4.3.6  Swath sampling f o r s t a n d i n g c r o p and seed w e i g h t 4.3.6.1 M a t e r i a l s and methods 4.3.6.2 O b s e r v a t i o n s and r e s u l t s 4.3.6.3 D i s c u s s i o n  70 70 70 70  Sampling f o r N i t r o g e n - f i x i n g A c t i v i t y  74  4.4.1 4.4.2 4.4.3  74 74 75  M a t e r i a l s and methods O b s e r v a t i o n s and r e s u l t s Discussion  vi 4.5  4.5.1 4.5.2 4.5.3 4.6  4.7  4.8  PAGE WO. 75  Mowing T r i a l s M a t e r i a l s and methods O b s e r v a t i o n s and r e s u l t s Discussion  75 75 75  Coated Seed T r i a l  77  4.6.1 4.6.2  77 77  M a t e r i a l s and methods O b s e r v a t i o n s and r e s u l t s  Fertilizer Trials  77  4.7.1 4.7.2  77 78  M a t e r i a l s and methods O b s e r v a t i o n s and r e s u l t s  Sampling f o r Cyanogenesis 4.8.1 4.8.2 4.8.3  i n C r e s t o n White C l o v e r  M a t e r i a l s and methods O b s e r v a t i o n s and r e s u l t s Discussion  78 78 78 78  B.  S t u d i e s u n d e r t a k e n a t t h e U n i v e r s i t y o f B.C.  79  4.9  S t r a i n E v a l u a t i o n u s i n g Groups o f S i n g l e P l a n t s  79  4.9.1  G e n e r a l comments on e x p e r i m e n t a l d e s i g n and l a y o u t  79  4.9.2  V a r i a t i o n i n f l o w e r i n g by date 4.9.2.1 M a t e r i a l s and methods 4.9.2.2 O b s e r v a t i o n s and r e s u l t s 4.9.2.3 D i s c u s s i o n  79 79 81 81  4.9.3  V a r i a t i o n i n l e a f area  87  4.9.3.1 4.9.3.2 4.9.3.3  87 88 88  M a t e r i a l s and methods O b s e r v a t i o n s and r e s u l t s . Discussion  4.9.4' V a r i a t i o n i n p e t i o l e l e n g t h 4.9.4.1' M a t e r i a l s and methods '4.9.4.2 O b s e r v a t i o n s ' a n d r e s u l t s 4\9.4.3 D i s c u s s i o n  94 94 94 94  4.9.5  V a r i a t i o n i n l e a f shape and markings 4.9.5.1 M a t e r i a l s and methods 4.9.5.2 O b s e r v a t i o n s and r e s u l t s 4.9.5.3 D i s c u s s i o n  99 99 99 104  4.9.6  V a r i a t i o n i n plant height 4.9.6.1 M a t e r i a l s and methods 4.9.6.2 O b s e r v a t i o n s and r e s u l t s 4.9.6.3 D i s c u s s i o n  104 104 104 104  4.9.7  V a r i a t i o n i n cyanogenesis 4.9.7.1 M a t e r i a l s and methods 4.9.7.2 O b s e r v a t i o n s and r e s u l t s 4.9.7.3 D i s c u s s i o n  109 109 109 109  vii 4.9.8  4.10  4.11  4.12  Variation 4.9.8.1 4.9.8.2 4.9.8.3  i n p l a n t weight M a t e r i a l s and methods O b s e r v a t i o n s and r e s u l t s Discussion  PAGE NO. 110 110 110 110  V a r i a t i o n w i t h i n and between Clones  110  4.10.1  Comment on t r i a l l a y o u t  110  4.10.2  V a r i a t i o n i n l e a f area 4.10.2.1 M a t e r i a l s and methods 4.10.2.2 O b s e r v a t i o n s and r e s u l t s  115 115 115  4.10.3  Variation i n p e t i o l e length 4.10.3.1 M a t e r i a l s and methods 4.10.3.2 O b s e r v a t i o n s and r e s u l t s  121 121 121  4.10.4  V a r i a t i o n i n p l a n t weight 4.10.4.1 M a t e r i a l s and methods 4.10.4.2 O b s e r v a t i o n s and r e s u l t s  121 121 121  4.10.5  V a r i a t i o n i n plant height 4.10.5-1 M a t e r i a l s and methods 4.10.5.2 O b s e r v a t i o n s and r e s u l t s  127 127 127  4.10.6  V a r i a t i o n i n l e a f markings 4.10.6.1 M a t e r i a l s and methods 4.10.6.2 O b s e r v a t i o n s and r e s u l t s  129 129 129  Coated C l o v e r Seed T r i a l  129  4.11.1  M a t e r i a l s and methods  129  4.11.2  O b s e r v a t i o n s and r e s u l t s  129  4.11.3  Discussion  131  Acetylene Reduction T r i a l s  131  4.12.1 4.12.2 4.12.3  131 131 132  M a t e r i a l s and methods O b s e r v a t i o n s and r e s u l t s Discussion  5.  GENERAL DISCUSSION AND CONCLUSIONS  133  6.  LITERATURE CITED  140  7.  APPENDIX  151  .viii LIST OF TABLES  Table  Page No.  1.1  L i s t i n g o f a c r e a g e , average y i e l d , t o t a l y i e l d s , p r i c e p e r pound and t o t a l v a l u e f o r w h i t e c l o v e r seed p r o d u c t i o n i n t h e C r e s t o n v a l l e y .  2  4.1.1  Average number o f w e e v i l s c o l l e c t e d by sweeping t h e f o l i a g e a t C r e s t o n ; numbers p r e s e n t e d f o r each s p e c i e s b y f i e l d and d a t e .  4.1.2  Average number o f organisms i n groups c o l l e c t e d by means o f s t i c k y t r a p s a t C r e s t o n ; numbers p r e s e n t e d f o r each group by f i e l d and d a t e .  4.1.3.1  Organisms c o l l e c t e d b y p i t - f a l l t r a p s a t C r e s t o n ; g r o u p i n g o f o r d e r s , f a m i l i e s , o r genus.  45  4.1.3.2  Organisms c o l l e c t e d i n p i t - f a l l t r a p s a t C r e s t o n ; dates o f c o l l e c t i o n .  46  4.1.3.3  Average number o f organisms i n groups c o l l e c t e d by means o f p i t - f a l l t r a p s a t C r e s t o n ; numbers p r e s e n t e d f o r each group by f i e l d and d a t e .  47  4.1.4.1  An e s t i m a t i o n o f r o o t damage by date t o w h i t e c l o v e r p l a n t s i n farmers' f i e l d s i n Creston.  50  4.1.4.2  Nematode counts o b t a i n e d by e x t r a c t i o n from s o i l - c l o v e r c o r e s from C r e s t o n .  52  4.3.1.1  Top weight samplings i n s i x f i e l d s i n C r e s t o n i n May 1977. -  55  4.3.2.1  Top weight samplings i n s i x f i e l d s i n C r e s t o n i n August 1977- . •  55  4.3.3.1  Seed w e i g h t s i n s i x f i e l d s i n C r e s t o n i n August.1977-  55  4.3.3.2  Number o f heads p e r u n i t a r e a i n s i x f i e l d s i n C r e s t o n , t a k e n i n August 1977-  59  4.3.3.3  Dependence o f seed y i e l d on number o f i n f l o r e s cences p e r u n i t a r e a . .  59  4.3.4.1  Number o f seeds p e r head i n s i x f i e l d s i n C r e s t o n , August 1977.  37  41  63  ix Table  Page No  4.3.4.2.  C o n t i n g e n c y t a b l e f o r insect-damaged seed from i n d i v i d u a l seed heads from C r e s t o n f i e l d s i n August 1977.  63  4.3.5.1  Average l e a f a r e a s i n square c e n t i m e t e r s f o r s i x f i e l d s i n C r e s t o n , i n J u l y 1977.  66  4.3.5-2  Average l e a f p e t i o l e l e n g t h s i n centimeters f o r s i x f i e l d s i n C r e s t o n , i n J u l y 1977.  66  4.3.5.3  Average ( i n f l o r e s c e n c e ) peduncle l e n g t h s i n centimeters f o r s i x f i e l d s i n Creston, i n J u l y 1977.  66  4.3.5.4  L i n e a r r e g r e s s i o n e q u a t i o n s and c o r r e l a t i o n c o e f f i c i e n t s , (Y) f o r l e a f a r e a and p e t i o l e l e n g t h of white c l o v e r i n s i x f i e l d s i n Creston.  4.3.6.1  Estimates o f standing crop y i e l d s obtained by s a m p l i n g swaths i n t h r e e C r e s t o n f i e l d s , August  71  1977. 4.3.6.2  E s t i m a t e s o f f i e l d seed y i e l d o b t a i n e d by samp l i n g swaths i n t h r e e C r e s t o n f i e l d s , August  71  1977. 4.4.1  Y i e l d o f n i t r o g e n i n kgs/ha f o r s t a n d i n g crops i n s i x Creston f i e l d s .  4.9.1.1  Weight o f seed from twenty s t r a i n s o f w h i t e c l o v e r p l a n t e d a t t h e U n i v e r s i t y o f B.C.  4.9.2.1  Twenty s t r a i n s grown a t t h e U n i v e r s i t y o f B.C. r a n k e d a c c o r d i n g t o average b l o s s o m number p e r plant.  82  4.9.2.2  Relationship of earliness i n flowering to the number o f i n f l o r e s c e n c e s produced.  86  4.9.3.1  Average l e a f a r e a i n square c e n t i m e t e r s f o r i n d i v i d u a l p l a n t s i n twenty s t r a i n s , grown i n a u n i f o r m n u r s e r y a t t h e U n i v e r s i t y o f B.C., sampling date: 20-7-77(1).  88  4.9.3.2  Average l e a f a r e a i n square i n d i v i d u a l p l a n t s i n twenty c l o v e r , grown i n a u n i f o r m U n i v e r s i t y f B.C. s a m p l i n g  90  Q  76  "  centimeters f o r strains of white nursery at the d a t e : : 13-10-77(2).  80  X  Page No.  Table  4.9.3.3  C o n t i n g e n c y t a b l e and C h i - s q u a r e v a l u e s f o r average l e a f a r e a f o r twenty s t r a i n s grown a t t h e U n i v e r s i t y o f B.C., sampled on t h e 20-7-77-  92  4.9.3.4  C o n t i n g e n c y t a b l e and C h i - s q u a r e v a l u e s f o r average l e a f a r e a f o r twenty s t r a i n s grown a t t h e U n i v e r s i t y o f B.C., sampled on t h e 13-10-77-  93  4.9.4.1  Average p e t i o l e l e n g t h i n c e n t i m e t e r s f o r i n d i v i d u a l p l a n t s i n twenty s t r a i n s grown i n a u n i form n u r s e r y a t t h e U n i v e r s i t y o f B.C., sampling date: 20-7-77.  95  4.9.4.2  Average p e t i o l e l e n g t h i n c e n t i m e t e r s f o r i n d i v i d u a l p l a n t s i n twenty s t r a i n s grown i n a u n i form n u r s e r y a t t h e U n i v e r s i t y o f B.C., s a m p l i n g date: 13-10-77-  96  4.9.4.3  Relationship of l e a f area t o p e t i o l e length; measurements t a k e n t h e 20-7-77•  97  4.9.4.4  Relationships of l e a f area t o p e t i o l e length; measurements t a k e n t h e 13-10-77-  98  4.9.5.1  Contingency t a b l e and C h i - s q u a r e v a l u e s f o r w h i t e c l o v e r l e a f shapes.  100  4.9.5.2  R a t i o o f water marks t o no w a t e r marks f o r twenty s t r a i n s o f w h i t e c l o v e r , grown a t t h e U n v i e r s i t y o f B.C. • • . •  101  4.9.5.3  Contingency t a b l e and C h i - s q u a r e v a l u e s f o r f o u r c l a s s e s o f l e a f markings i n 20 s t r a i n s , o f w h i t e c l o v e r grown a t t h e U n i v e r s i t y o f B.C. '  102  4.9.5.4  R a t i o o f a n t h o c y a n i n f l e c k i n g t o no f l e c k i n g f o r twenty s t r a i n s o f w h i t e c l o v e r grown a t t h e U n i v e r s i t y o f B.C.  103  4.9.5.5  Contingency t a b l e and C h i - s q u a r e v a l u e s f o r ant h o c y a n i n f l e c k i n g i n twenty s t r a i n s o f w h i t e c l o v e r grown a t t h e U n i v e r s i t y o f B.C.  105  4.9.5.6  C o n t i n g e n c y t a b l e f o r w h i t e c l o v e r l e a f markings and a n t h o c y a n i n l e a f f l e c k i n g on twenty s t r a i n s grown a t t h e U n i v e r s i t y o f B.C.  1,06  4.9.6.1  Plant height i n centimeters f o r i n d i v i d u a l plants i n twenty s t r a i n s grown a t t h e U n i v e r i s t y o f B.C.  107  xi Table  'Page No.  4.9.8.1  I n d i v i d u a l p l a n t w e i g h t s i n gms. f o r twenty s t r a i n s grown a t t h e U n i v e r s i t y o f B.C., samp l i n g date: 18-8-77(1).  111  4.9.8.2  I n d i v i d u a l p l a n t w e i g h t s i n gms. f o r twenty s t r a i n s grown i n a u n i f o r m n u r s e r y a t t h e U n i v e r s i t y o f B.C., sampling date: 19-10-77(2).  113  4.10.2.1  Area^representation o f i n d i v i d u a l leaves ( i n square c e n t i m e t e r s ) f o r f i v e s t r a i n s o f w h i t e c l o v e r a t t h e U n i v e r s i t y o f B.C., sampled 20-7-77 (!)•• •  116  4.10.2.2  Area representation of i n d i v i d u a l leaves ( i n square c e n t i m e t e r s ) f o r f i v e s t r a i n s o f w h i t e c l o v e r a t t h e U n i v e r s i t y o f B.C., sampled 20-10-77(2). . . . .  116  4.10.2.3  Mean l e a f a r e a v a r i a b i l i t y w i t h i n c l o n e s o f f i v e s t r a i n s o f w h i t e c l o v e r grown i n a u n i f o r m nurs e r y a t t h e U n i v e r i s t y o f B.C.; c o l l e c t i o n d a t e : 20-7-77.  119  4.10.2.4  Mean l e a f v a r i a b i l i t y w i t h i n c l o n e s o f f i v e s t r a i n s o f w h i t e c l o v e r grown i n a u n i f o r m n u r s e r y a t t h e U n i v e r s i t y o f B.C.; c o l l e c t i o n date: 20-10-77-  120  4.10.3.1  P e t i o l e length i n centimeters f o r f i v e s t r a i n s o f w h i t e c l o v e r grown i n a u n i f o r m n u r s e r y a t t h e U n i v e r s i t y o f B.C., sampled: 20-7-77-  122  4.10.3.2  P e t i o l e length i n centimeters f o r f i v e s t r a i n s o f w h i t e c l o v e r grown i n a u n i f o r m n u r s e r y a t the U n i v e r s i t y o f B.C., sampled 20-10-77-  122  4.10.3.3  L i n e a r r e g r e s s i o n e q u a t i o n s and c o r r e l a t i o n c o e f f i c i e n t s < f o r white clover c l o n a l material f o r two dates grown i n a u n i f o r m n u r s e r y a t t h e U n i v e r s i t y o f B.C. . . . . . •  123  4.10.4.1  Top.weight i n grams f o r f i v e s t r a i n s o f w h i t e c l o v e r grown i n a u n i f o r m n u r s e r y a t t h e U n i v e r s i t y o f B.C. - • . . . ,  124  4.10.5.1  Height i n centimeters f o r f i v e s t r a i n s o f white c l o v e r grown i n a u n i f o r m n u r s e r y a t t h e U n i v e r s i t y o f B.C. , _  124 .  xii Page No.  •Table  4.10.4.2  -Mean w i g h t and s t a n d a r d d e v i a t i o n o f t o p growth w i t h i n c l o n e s from f i v e s t r a i n s o f w h i t e c l o v e r grown a t t h e U n i v e r s i t y o f B.C.  126  4.10.5.2  Mean p l a n t h e i g h t and s t a n d a r d d e v i a t i o n w i t h i n c l o n e s from f i v e s t r a i n s o f w h i t e c l o v e r grown at t h e U n i v e r s i t y o f B.C.  126  4.10.6.1  Counts o f l e a f marks f o r f i v e s t r a i n s o f w h i t e c l o v e r grown as c l o n a l m a t e r i a l a t t h e U n i v e r s i t y o f B.C.  130  4.10. 6. 2  Contingency t a b l e and C h i - s q u a r e v a l u e s f o r i n v e r t e d l e a f marks and a n t h o c y a n i n f l e c k i n g on c l o n a l m a t e r i a l a t t h e U n i v e r s i t y o f B.C.  130  xiii  LIST OF ILLUSTRATIONS  Figure  Page No.  .3.1.1  Average t e m p e r a t u r e , p r e c i p i t a t i o n and f r o s t f r e e p e r i o d a t C r e s t o n , B.C.  23  3.1.2  A e r i a l photograph o f f i e l d 1.  25  3.1.3  A e r i a l photograph o f f i e l d 2.  25  3.1.4  A e r i a l photograph o f f i e l d s . 3, 4 and 5.  27  3.1.5  A e r i a l photograph o f f i e l d 6.  30  3.2.1  Average t e m p e r a t u r e , p r e c i p i t a t i o n and f r o s t f r e e p e r i o d a t t h e U n i v e r s i t y o f B.C.  35  4.1.1  W e e v i l s c o l l e c t e d b y means o f sweeping t h e f o l i a g e i n s i x f i e l d s i n the Creston Valley.  38  4.1.2.1  Assessment o f s t i c k y s t r a p s . a t I C r e s t a n .  42  4.1.2.2  I n s e c t s caught on s t i c k y t r a p s i n t h e C r e s t o n v a l l e y i n three f i e l d s .  43  4.1.3  Graph showing i n s e c t s c o l l e c t e d i n p i t - f a l l traps i n the Creston v a l l e y i n three f i e l d s .  4.3.1.1  The v a r i a t i o n i n w e i g h t o f t o p growth i n s i x f i e l d s i n C r e s t o n , May 30, 1 9 7 7 ( 1 ) .  4.3.2.1  The v a r i a t i o n i n w e i g h t o f t o p growth i n s i x f i e l d s i n C r e s t o n , August 1977 ( 2 ) .  4.3.3.1  The v a r i a t i o n i n w e i g h t o f seed from s i x f i e l d s i n C r e s t o n , August 1977-  4.3.3.2  The v a r i a t i o n i n t h e number o f heads p e r u n i t a r e a i n s i x f i e l d s i n C r e s t o n , August 1977-  4.3.4.1  The v a r i a t i o n i n number o f seeds p e r head i n s i x f i e l d s i n C r e s t o n , August 1977.  4.3.5.1  The v a r i a t i o n i n l e a f a r e a i n s i x f i e l d s i n C r e s t o n , J u l y 1977-  xiv  Page No,  •Figure 4.3.5.2  The v a r i a t i o n i n l e a f p e t i o l e l e n g t h f o r s i x f i e l d s i n C r e s t o n , J u l y 1911.  68  4.3.5-3  The v a r i a t i o n i n i n f l o r e s c e n c e peduncle l e n g t h f o r s i x f i e l d s i n t h e C r e s t o n v a l l e y , J u l y 1977-  69  4.3.6.1  The v a r i a t i o n i n s t a n d i n g crop i n t h r e e C r e s t o n f i e l d s , August 1977.  72  4.3.6.2  The v a r i a t i o n i n t h e w e i g h t o f seed from t h r e e f i e l d s i n C r e s t o n , August 1977.  73  4.9.2.1  The response i n f l o w e r i n g by twenty s t r a i n s o f w h i t e c l o v e r on t h e 8-6-77.  83  4.9.2.2  The response i n f l o w e r i n g by twenty s t r a i n s o f w h i t e c l o v e r on t h e 22-6-77.  84  4.9.2.3-  The response i n f l o w e r i n g by twenty s t r a i n s o f " w h i t e c l o v e r on t h e 19-7-77.  85  4.9.3.1  The v a r i a t i o n i n l e a f a r e a on t h e 20-7-77 ( l ) f o r twenty s t r a i n s .  89  4.9.3.2  The v a r i a t i o n i n l e a f a r e a on t h e 13-10-77 (.2) f o r twenty s t r a i n s .  91  4.9.6.1  The v a r i a t i o n i n p l a n t h e i g h t f o r twenty s t r a i n s .  108  4.9-8.1  The v a r i a t i o n i n s t a n d i n g c r o p weight from t h e h a r v e s t on t h e 18-8-77 ( l ) o f w h i t e c l o v e r p l a n t s from twenty s t r a i n s .  112  4.9.8.2  The v a r i a t i o n i n s t a n d i n g crop weight from h a r v e s t on t h e 19-19-77 (2) o f w h i t e c l o v e r p l a n t s from twenty s t r a i n s .  114  4.10.2.1  The v a r i a t i o n i n l e a f a r e a on t h e 20-7-77 ( l ) ; p l a n t s were grown from c u t t i n g s .  117  4.10.2.2  The v a r i a t i o n i n l e a f a r e a on t h e 20-10-77 ( 2 ) ; p l a n t s were grown from c u t t i n g s .  118  4.10.4.1  The v a r i a t i o n i n t o p w e i g h t f o r p l a n t s grown from c u t t i n g s .  125  4.10.5-1  The v a r i a t i o n i n h e i g h t o f w h i t e c l o v e r p l a n t s grown from c u t t i n g s .  128  XV  Figure  Page No.  7.1  The C r e s t o n v a l l e y i n s o u t h - e a s t e r n B.C. i s suitable f o r the production of high q u a l i t y w h i t e c l o v e r seed.  151  7.2(a)  W h i t e c l o v e r r a n k s as one o f t h e w o r l d ' s more i m p o r t a n t f o r a g e p l a n t s . . . i t s a p p l i c a t i o n i n o t h e r s i t u a t i o n s i n i n c r e a s i n g ( e . g . range rehabilitation).  151  7.2(b)  Open g r a s s l a n d .  152  7.2(c)  F o r e s t e d range.  152  7.3(a)  . . . f i f t y p e r c e n t o f t h e v e g e t a t i v e growth o f w h i t e c l o v e r , on t h e C r e s t o n f l a t s , t a k e s p l a c e p r i o r t o t h e end o f May.  153  7.3(b)  Creston s t r a i n s , w i t h l e s s f a l l recovery i n top growth, should d i s p l a y a g r e a t e r p e r s i s t e n c e .  153  7.4(a)  The a c t i o n o f t h e c l o v e r r o o t c u r c u l i o l a r v a e l e a d s t o a weakening o f t h e s t a n d , weed i n f e s t a t i o n . .. .pathogen e n t r y and l o s s o f p l a n t persistence.  154  7.4(b)  O t h e r organisms such as s l u g s , nematodes and r o d e n t s ... t h e i r p r e s e n c e ... o b s e r v e d t o be sporadic.  154  7.4(c)  ...even weeds o f low s t a t u r e such as d a n d e l i o n .  155  7.4(d)  ...and o f c o u r s e t a l l weeds such as p e r e n n i a l sow t h i s t l e .  155  7.5(a)  V o l u n t e e r g r a i n from p r e v i o u s y e a r s h a r v e s t .  156  7.5(b)  ...long stubble remaining a f t e r three previous y e a r ' s g r a i n h a r v e s t . . . such o b s t r u c t i o n s c o u l d l e a d t o poor bee a c t i v i t y .  156  7.6  The s t i c k y t r a p s c o n s i s t e d o f 9 i n c h by 11 i n c h y e l l o w r a i l r o a d board.  157  7.7(a)  W h i t e c l o v e r i n c e r t a i n areas o f d i f f e r e n t s o i l t e x t u r e would f l o w e r prematurely.  157  7.7(b)  F l o w e r i n g i n e a r l y June.  158  xvi  Figure 7.7(c)  Matured by l a t e June.  7.8  The average number o f i n f l o r e s c e n c e s p e r hect a r e was e s t i m a t e d t o be 11.5 m i l l i o n .  7.9  B e e h i v e s a r e r o u t i n e l y p l a c e d i n each crop o f white clover.  7.10(a)  H a r v e s t i n g g e n e r a l l y commences when 90% o f t h e heads a r e "brown".  7.10(b)  Farmers a r e e x p e r i e n c i n g a seed l o s s , w h i l e h a r v e s t i n g , o f up t o 50%.  7.11(a)  I t . i s i m p o s s i b l e f o r t h e farmer t o keep t h e c r o p l o n g e r t h a n on seed h a r v e s t .  7.11(b)  . C h i s e l ploughed.  7.12  C o n s e q u e n t l y t h e t r i a l was abandoned.  7.13  White c l o v e r i s a s h o r t - l o n g day s p e c i e s and d i f f e r e n t s t r a i n s respond i n f l o w e r i n g t o d i f f e r e n t combinations o f t e m p e r a t u r e and daylength.  7.14(a)  F r e e f l o w e r i n g s t r a i n s a r e i m p o r t a n t f o r seed production.  7.14(b)  The p e t a l s a r e w h i t e b u t a r e o c c a s i o n a l y  7.15(a)  L o u i s i a n a . s t r a i n s s t o o d out by t h e i r c o n s i s t e n t presence o f t h e i n v e r t e d "V" l e a f mark.  7.15(b)  P l a n t s w i t h no l e a f markings were i n t h e m i n o r i t y  pink.  xvdi ACKNOWLEDGEMENTS A p p r e c i a t i o n i s extended t o my graduate  committee:  D r . V.C. Rune'ckles  (Chairman), Department o f P l a n t S c i e n c e ; D r . V.C. B r i n k , Department o f P l a n t S c i e n c e ; D r . A . J . Renney, Department o f P l a n t S c i e n c e ; D r . R.H. E l l i o t t , Department o f P l a n t S c i e n c e ; D r . C A . Rowles, Department o f S o i l S c i e n c e , arid Mr. J.V. Z a c h a r i a s , Head, F i e l d Crops Branch, B r i t i s h Columbia Department o f Agriculture.  Acknowledgement i s a l s o g i v e n t o D r . G.W. E a t o n , Department o f  P l a n t S c i e n c e , f o r h i s a d v i c e on s t a t i s t i c a l a n a l y s i s , and t o Dr. R. Copeman, Department o f P l a n t S c i e n c e , f o r e x a m i n a t i o n o f m a t e r i a l f o r pathogens. F i n a n c i a l a i d , g r a t e f u l l y acknowledged, has been p r o v i d e d t h r o u g h t h e A g r i c u l t u r a l S c i e n c e s Research  and Development f u n d .  S p e c i a l thanks f o r t h e i r f i e l d support and c o o p e r a t i o n i n C r e s t o n a r e t o be accorded:  Mr. S.S. D h i n d s a , F i e l d Crops Branch, B r i t i s h Columbia  Department o f A g r i c u l t u r e , and Mr. R. F r a n c e , D i s t r i c t A g r i c u l t u r i s t , Columbia Department o f A g r i c u l t u r e , C r e s t o n , B.C.  British  S p e c i a l thanks a r e a l s o  accorded t o Dr. F. M c E l r o y , A g r i c u l t u r e Canada R e s e a r c h  S t a t i o n , Vancouver, B.C.  T e c h n i c a l a s s i s t a n c e , g r a t e f u l l y acknowledged, has been p r o v i d e d b y Mr. I l m a r s D e r i e s , S e n i o r T e c h n i c i a n , Department o f P l a n t S c i e n c e , f o r t h e c o n s t r u c t i o n o f an e t h y l e n e a n a l y z e r , f o r h e l p i n t h e d e t e r m i n a t i o n o f n i t r o g e n and p r e p a r a t i o n o f s l i d e s .  A l s o Mr. D. P e a r c e , S e n i o r T e c h n i c i a n , and'  Mr. D. A r m s t r o n g , T e c h n i c i a n , Department o f P l a n t S c i e n c e , U n i v e r s i t y o f B r i t i s h Columbia, a r e thanked  f o r t h e i r a s s i s t a n c e i n f i e l d and greenhouse.  S p e c i a l thanks i s extended t o T a l i s m a n P r o j e c t s , Vancouver, B.C., f o r t h e d r a f t i n g o f f i g u r e s and graphs. F i n a l l y , I am i n d e b t e d t o my F a c u l t y S u p e r v i s o r , D r . V.C. B r i n k , Department o f P l a n t S c i e n c e , f o r s u g g e s t i o n o f t h i s t o p i c , f o r h i s keen i n t e r e s t , a d v i c e and h e l p i n t h e l a b o r a t o r y , c l a s s r o o m and f i e l d .  1  1.  INTRODUCTION The C r e s t o n v a l l e y i n south e a s t e r n B r i t i s h Columbia i s s u i t a b l e f o r  p r o d u c t i o n o f h i g h q u a l i t y c l o v e r seed.  Furthermore t h e v a l l e y has become,  d u r i n g t h e l a s t few decades, one o f t h e more i m p o r t a n t areas f o r w h i t e c l o v e r seed p r o d u c t i o n i n Canada. and s t i l l  The c r o p has been f o r s e v e r a l decades  i s an a t t r a c t i v e and i m p o r t a n t c o n s t i t u e n t o f t h e c r o p p i n g  systems i n t h e C r e s t o n v a l l e y . W i t h i n r e c e n t y e a r s , seed y i e l d s have d e c l i n e d i n t h e f i r s t and subsequent y e a r s o f p r o d u c t i o n (see T a b l e 1.1). One o f t h e o b j e c t i v e s o f t h i s r e s e a r c h i s a s e a r c h f o r t h e major causes o f t h e seed y i e l d d e c l i n e . Two i m p o r t a n t f a c t o r s make t h e l o c a l i n d u s t r y worthy o f c l o s e s c r u t i n y and support.  F i r s t , w h i t e c l o v e r , a leguminous c r o p w i t h a h i g h p o t e n t i a l f o r  t h e f i x a t i o n o f atmospheric  n i t r o g e n , f i t s i n w e l l w i t h the a g r i c u l t u r a l  c r o p p i n g systems o f t h e C r e s t o n v a l l e y . c l o v e r seed i s m o d e r a t e l y  Second, t h e B.C. market f o r w h i t e  l u c r a t i v e and, i n a d d i t i o n , markets a r e open i n  t h e U n i t e d S t a t e s and o v e r s e a s . A second o b j e c t i v e o f t h e r e s e a r c h was t o study t h e w i t h i n s t r a i n v a r i a b i l i t y w i t h a view t o d e t e r m i n i n g t h e s u i t a b i l i t y o f t h e C r e s t o n  white  c l o v e r s t o c k s f o r d e s i g n a t i o n as a l a n d s t r a i n . S t u d i e s o f seed p r o d u c t i o n i n w h i t e c l o v e r have not been r e p o r t e d i n Canada, t h e r e f o r e t h i s s t u d y i s e x p l o r a t o r y and broad; i t i s hoped that additional studies w i l l  follow.  2  Table  1.1 H e c t a r a g e , average y i e l d , t o t a l y i e l d ,  price  per k i l o g r a m and t o t a l v a l u e f o r w h i t e c l o v e r seed p r o d u c t i o n i n the C r e s t o n v a l l e y . Year  Hectares  Average y i e l d  1966  771  607 kgs/ha  1967  -  1968  918  1969  Total  yield  Price/kg  Total v a l  468,566 kg  -  -  301,869 kg  -  -  492 kgs/ha  453,597 kg  77*  $350,000  891  358 kgs/ha  319,786 kg  90*  290,000  1970  761  448 kgs/ha  341,105 kg  165*  564,000  1971  709  560 kgs/ha  396,897 kg  71*  280,000  1972  640  448 kgs/ha  286,673 kg  99*  284,000  1973  607  280 kgs/ha  170,099 kg  143*  243,750  1974  405  269 kgs/ha  108,863 kg  220*  240,000  1975  324  403 kgs/ha  130,636 kg  198*  259,000  1976  243  314 kgs/ha  76,204 kg  176*  134,000  1977  243  426 kgs/ha  103,420 kg  176*  182,400  -  -  3  2.  REVIEW OF RELEVANT LITERATURE  2.1  G e n e r a l B i o l o g y o f White C l o v e r White c l o v e r r a n k s as one o f t h e w o r l d ' s more i m p o r t a n t f o r a g e p l a n t s .  With i t s o r i g i n i n t h e M e d i t e r r a n e a n (Davies 1969) i t now enjoys an almost worldwide d i s t r i b u t i o n (Crowder  1960).  V a r i a t i o n s i n g r o s s morphology a r e everywhere  v e r y n o t i c e a b l e ; never-  t h e l e s s w i t h i n t h e genus T r i f o l i u m , a l a r g e genus, w h i t e c l o v e r  (Trifolium  repens) i s a w e l l d e f i n e d s p e c i e s (Chromosome No. 2n = 3 2 ) . A l t h o u g h t h e general b i o l o g y o f white clover i s the subject of several e a r l y r e p o r t s , n o t a b l y a monograph by E r i t h  (1924) and a b i b l i o g r a p h y ( I m p e r i a l Bureaux o f  P a s t u r e s and Forage Crops 1939), i t i s u s e f u l t o r e v i e w some o f t h e s a l i e n t features. 2.1.1  Nomenclature White c l o v e r i s a L i n n a e a n s p e c i e s and i s u n i v e r s a l l y r e c o g n i z e d i n  t e c h n i c a l nomenclature as T r i f o l i u m repens L.; o t h e r common names a r e w h i t e t r e f o i l ; w h i t e h o n e y s u c k l e ; shamrock; bubby-roses; q u i l l e t  (Erith  1924); w h i t e man's f o o t . 2.1.2  Agronomic Races Three forms o f w h i t e c l o v e r a r e i m p o r t a n t a g r o n o m i c a l l y ; t h e r a c e  " s y l v e s t r e " , known as w i l d w h i t e c l o v e r i s a s m a l l but hardy p l a n t .  It  enjoys a r e p u t a t i o n f o r p e r s i s t e n c y i n long-term p a s t u r e s and h i l l p a s t u r e s i n Great B r i t a i n and o t h e r p a r t s o f t h e w o r l d .  The r a c e " h o l -  l a n d i c u m " , known as "common w h i t e " o r " w h i t e Dutch" ( o r i g i n H o l l a n d ) , does not have t h e p e r s i s t e n c y o f w i l d w h i t e c l o v e r b u t i s a l a r g e r p l a n t i n form and i s sometimes r e f e r r e d t o as " i n t e r m e d i a t e " w h i t e c l o v e r .  Place  o f o r i g i n f o r common w h i t e seed s t o c k s has r e s u l t e d i n names such as New  4 Zealand w h i t e ,  K e n t i s h w h i t e , L o u i s i a n a w h i t e ( H o l l o w e l l 1948).  w h i t e i s s u i t e d t o mixed l e y s o f s h o r t t o moderate d u r a t i o n The  (1-5  years).  r a c e "giganteum", commonly known as " L o d i " o r " L a d i n o " i s s i m i l a r i n  almost a l l r e s p e c t s mammoth form.  t o t h e above two forms mentioned but has a " g i g a s " o r  I t y i e l d s a g r e a t e r amount o f d r y m a t t e r t h a n t h e h o l l a n d -  icum r a c e and i s commonly grown f o r hay and s h o r t - t e r m 2.1.3  Common  pastures.  Strains As mentioned p r e v i o u s l y w h i t e c l o v e r i s g r e a t l y v a r i a b l e i n i t s form  and performance.  However, i t i s p o s s i b l e t o group p l a n t s t h a t have c e r t a i n  s a l i e n t f e a t u r e s i n common y e t a r e n o t n e c e s s a r i l y i d e n t i c a l .  F o r conven-  i e n c e i t i s customary t o a s s i g n t h e name " s t r a i n " o r l e s s commonly " c u l t i v a r " ( v a r i e t y ) (Hawkins 1953 and 1960).  Hawkins (1959) l i s t s s e v e r a l i n h e r i t e d  measurable c h a r a c t e r i s t i c s o f w h i t e c l o v e r t h a t a r e u s e f u l f o r s t r a i n i c a t i o n and i d e n t i f i c a t i o n .  When a s s i g n e d  classif-  a name o r number, t h i s t e l l s us t h e  p l a n t ' s o r i g i n , t y p e and s u i t a b i l i t y t o c e r t a i n uses (Ware 1925). p o i n t i s t h e A b e r y s t w y t h s t r a i n , S.184 w i l d w h i t e c l o v e r .  A case i n  English w i l d white  c l o v e r , known f o r i t s p e r s i s t e n c y , i s i n form and b e h a v i o u r q u i t e v a r i a b l e . However by s e l e c t i o n a t t h e Welsh p l a n t b r e e d i n g s t a t i o n a t A b e r y s t w y t h a p e d i g r e e d s t r a i n S.184 w i l d w h i t e c l o v e r was r e l e a s e d .  T h i s s t r a i n has a  g r e a t e r degree o f u n i f o r m i t y w i t h improved performance ( J e n k i n 1943). According misleading represented  t o U.S.D.A. r e p o r t s  (1947) t h e use o f t h e name White Dutch i s  s i n c e i t no l o n g e r r e p r e s e n t s an i n t e r m e d i a t e  f o r common w h i t e c l o v e r .  any p a r t i c u l a r t y p e .  A t one time i t  t y p e o f w h i t e c l o v e r b u t i s now m e r e l y a synonym  This i s important,  s i n c e t h e use o f n a t i o n a l i t y  s e r v e s t o d e s c r i b e t h e type o f p l a n t r a t h e r t h a n j u s t t h e c o u n t r y (Ware 1925,  W i l l i a m s 1945).  of origin  I n Canada i t i s grown and marketed as White  Dutch w i t h no guarantee as t o i t s o r i g i n , performance o r u n i f o r m i t y .  5 U n d e r s t a n d a b l y s t r a i n s and v a r i e t i e s o f w h i t e c l o v e r p e r f o r m d i f f e r e n t l y i n t h e d i f f e r e n t g e o g r a p h i c r e g i o n s o f Canada.  The E n g l i s h w i l d  w h i t e and t h e D a n i s h s t r a i n s l a c k p e r s i s t e n c e i n p l a c e s such as B e a v e r l o d g e and Ottawa, y e t t h e y e n j o y moderate s u c c e s s a t A g a s s i z , B.C.  White  Dutch  and New Zealand s t r a i n s p e r f o r m w e l l a t Ottawa, y e t p o o r l y a t A g a s s i z (Dominion Department o f A g r i c u l t u r e 1941).  E l l i o t and Howe (1977) g i v e t h e  r e l a t i v e h a r d i n e s s and y i e l d s o f w h i t e c l o v e r i n t r o d u c t i o n s as t e s t e d a t Beaverlodge.  The L o u i s i a n a s t r a i n s showed poor h a r d i n e s s and seed  yield  w h i l e those s t r a i n s o f an o r i g i n from a more temperate r e g i o n d i s p l a y e d i n c r e a s e d h a r d i n e s s and seed 2.1.4  yield.  Seed The seed i s s m a l l (1000 seeds w e i g h i n g c a . 0.65 grams) and d e v e l o p s i n  a legume (the f r u i t ) where t h e average number o f seeds i s two t o t h r e e ( E r i t h 1924).  The t e s t a i s y e l l o w i n the m a j o r i t y o f cases b u t i n some cases i s  y e l l o w i s h brown o r b r o w n i s h r e d .  The seed c o a t i n some seeds i s so imperm-  eable to moisture that germination i s delayed f o r years.  This condition  known as "hard seed" e x i s t s i n about 10% o f m e c h a n i c a l l y h a r v e s t e d seeds i n the common w h i t e ( U n i t e d S t a t e s Department o f A g r i c u l t u r e 1915).  Robinson  (1937) c l a i m s t h a t t h i s c o n d i t i o n i s brought about by o v e r - r i p e n e s s o f t h e f l o w e r heads a t h a r v e s t . 2.1.5  Germination i s epigeal.  A e r i a l Development The main stem i s v e r y s h o r t and t h e b r a n c h e s , known as s t o l o n s , a r e  c r e e p i n g and r o o t a t almost every node ( i . e . shoot growth i s i n d e t e r m i n a t e ) . I t i s from t h e s e nodes a l s o t h a t t h e l e a f and f l o w e r buds o r i g i n a t e . l e a f i s palmate and t r i f o l i a t e b e i n g b o r n on a l o n g p e t i o l e .  The  Character-  i s t i c d i u r n a l and n o c t u r n a l l e a f l e t p o s i t i o n s a r e p r o b a b l y . - a t t a i n e d by photonastic*' movement ( E r i t h 1924).  Brougham (1958) and Denne (1966)  6 suggest t h a t p e t i o l e and l e a f e x p a n s i o n c o n t i n u e of those p l a n t p a r t s .  The average l i f e o f a l e a f and i t s p e t i o l e i s  a p p r o x i m a t e l y f o r t y days a f t e r l e a f e x p a n s i o n . l e n g t h do n o t d i f f e r g r e a t l y under n u r s e r y biotic  f o r almost t h e e n t i r e l i f e  Leaf s i z e and p e t i o l e  c o n d i t i o n s b u t may change under  ( g r a z i n g ) , e d a p h i c and c l i m a t i c i n f l u e n c e s (Caradus 1977, King  1961).  There a r e p o s i t i v e c o r r e l a t i o n s between p l a n t h e i g h t , w e i g h t , r o s e t t e d i a m e t e r and l e a f a r e a ( B a r c i k o w s k a 1976, B e i n h a r t  1963).  Leaves produced  e a r l y i n t h e growing season tend t o be l a r g e r than l e a v e s produced l a t e r i n the season ( B e i n h a r t  1963).  D e f o l i a t i o n i s reported  t o reduce t h e s i z e o f  l e a v e s and t h e l e n g t h o f p e t i o l e s ( C a r l s o n 1966, King e t a l . 1978).  Observ-  a t i o n s by Davies (1958) suggest t h a t good l e a f y c u t s o f w h i t e c l o v e r can be t a k e n i n June i n B r i t a i n b u t subsequent crops a r e l e s s l e a f y . c l a i m s t h a t under h i s c o n d i t i o n s , t h e i n t e r m e d i a t e  White Dutch s t r a i n s  g i v e t h e h i g h e s t v e g e t a t i v e y i e l d s over a t h r e e - y e a r 2.1.6  Reproductive The  He a l s o  period.  Structures  i n f l o r e s c e n c e i s a dense raceme b o r n on a l o n g p e d u n c l e t h a t a r i s e s  from a l e a f a x i l on a s t o l o n o r p r o s t r a t e stem.  I t i s made up o f 10 t o 80  f l o r e t s ; the petals are white but are o c c a s i o n a l l y pink.  The s p e c i e s i s  almost always g e n e t i c a l l y s e l f - i n c o m p a t i b l e and c r o s s - f e r t i l i z a t i o n i s n e c e s s a r y (Atwood 1942); t h e most i m p o r t a n t p o l l i n a t o r i s t h e domestic honey bee.  Because o f c r o s s p o l l i n a t i o n and t h e s e l f - i n c o m p a t i b i l i t y p l a n t  breeding i n white clover i s d i f f i c u l t .  Most s t r a i n s , t h a t a r e i n use, a r e  the r e s u l t o f t h e p r o c e s s o f n a t u r a l s e l e c t i o n w i t h o n l y i n c i d e n t a l h e l p by man ( H o l l o w e l l 1948) . As w e l l as s e x u a l p r o p a g a t i o n , a s e x u a l l y by means o f s t o l o n s . clones  i n local habitats.  white clover i s able to maintain  itself  T h i s ensures d i s p e r s i o n and p e r s i s t e n c e o f  Work by Harberd (1963) showed t h a t c l o n e s a r e  7 known to have s u r v i v e d l o n g e r t h a n s i x t y y e a r s and  t o have spread o v e r an  a r e a o f twenty y a r d s d i a m e t e r . 2.1.7  Root Systems White c l o v e r r o o t systems a r e as v a r i e d as the forms o c c u r r i n g above  ground.  The  main stem.  w i l d r a c e s have a f i b r o u s r o o t system and no t a p r o o t on  the  On the o t h e r hand the Ladino r a c e has a d i s t i n c t t a p r o o t  but  few f i b r o u s r o o t s (Caradus 1977).  The  common o r White Dutch i s i n t e r m e d i a t e  i n t h a t i t has a g o o d l y number o f f i b r o u s r o o t s w h i l e a d v e n t i t i o u s r o o t s o c c u r a t almost every node of the s t o l o n . 2. 2  B i o l o g i c a l Nitrogen F i x a t i o n The v i r t u e s o f legumes i n green manuring have been acknowledged by  the a n c i e n t s .  However i t was  not u n t i l 1890  t h a t H e l l r i e g e l and W i l f a r t h  demonstrated c o n c l u s i v e l y t h a t n i t r o g e n f i x a t i o n o c c u r r e d the r o o t n o d u l e s o f legumes.  Much o f the e a r l y l i t e r a t u r e on n i t r o g e n  a t i o n has been r e v i e w e d by W i l s o n Recently,  symbiotically in fix-  (1940).  e s p e c i a l l y w i t h the i n s t i t u t i o n of the I n t e r n a t i o n a l B i o l o g -  i c a l Programme, s e v e r a l major t e x t s have appeared on the broad s u b j e c t b i o l o g i c a l n i t r o g e n f i x a t i o n (Burns and Hardy 1975, Hardy and G i b s o n 1977,  L i e 1971,  Nutman 1976,  Hardy and  Quispel  1974,  trifolii).  The  1976)  1977,  Stewart 1966).  N i t r o g e n f i x a t i o n by w h i t e c l o v e r o c c u r s as a r e s u l t o f a ( V i n c e n t 1974,  Silver  of  symbiotic  r e l a t i o n s h i p between the p l a n t and b a c t e r i a (Rhizobium  b a c t e r i a l Rhizobia that i n f e c t white c l o v e r roots  s p e c i f i c t o t h e c l o v e r (genus T r i f o l i u m ) group. group of b a c t e r i a on o t h e r l e g u m i n o i d  are  C r o s s i n n o c u l a t i o n by  groups such as the a l f a l f a group o r  the l u p i n groups, w i l l l e a d t o degrees of i n e f f e c t i v e nodules ( W i l s o n Annual amounts o f n i t r o g e n f i x e d by w h i t e c l o v e r a r e Estimates  this  1940).  significant.  by workers on the amount o f n i t r o g e n f i x e d by the w h i t e c l o v e r  8 system have been as h i g h as 616 kgs o f e l e m e n t a l  n i t r o g e n per hectare per  annum (Dobson and Beaty 1977, H a l l i d a y and Pate 1976, Haystead and Low 1977, Jones e t a l . 1977, K l e t e r and Bakhuis 1972, Walker e t a l . 1954, W i l l i a m s 1969).  Non s y m b i o t i c b i o l o g i c a l systems, by comparison, have been documented  to f i x no more than 70 pounds p e r a c r e p e r year ( W i l l i a m s 1969).  Under u s u a l  farm p r a c t i c e s amounts o f N f i x e d a r e commonly low - o f t e n below 170 kgs N per  hectare. Many c o n d i t i o n s d i c t a t e t h e a v a i l a b i l i t y o f f i x e d n i t r o g e n a s s o c i a t e d  species. E x c r e t i o n appears t o be a r e a d y s o u r c e o f t r a n s f e r e n c e 1977, V i r t a n e n e t a l .  (Mulder e t a l .  1937) whereas senescence o f n o d u l e s , r o o t s and t o p  growth l i b e r a t e n i t r o g e n o v e r a l o n g e r p e r i o d o f time (Walker e t a l . 1954). I t i s a l s o suggested (Walker et a l . 1954) t h a t t h e r e i s a d i r e c t r e l a t i o n s h i p between t h e amount o f n i t r o g e n r e t a i n e d by c l o v e r and t h e c o n t r i b u t i o n by clover to grasses.  C l o v e r s have been shown t o make a v a i l a b l e t o o t h e r  assoc-  i a t e d s p e c i e s , n o t a b l y g r a s s e s , as much n i t r o g e n as t h e y r e t a i n i n t h e i r aerial parts.  F i x e d n i t r o g e n from e x c r e t i o n and from d e c a y i n g o r g a n i c and  o t h e r s o i l systems a r e confounded and i t i s d i f f i c u l t expressions  to a s s i g n q u a n t i t a t i v e  t o t h e components.  It i s considered  t h a t c l o v e r i s i n e f f i c i e n t i n comparison t o many o t h e r  h i g h e r p l a n t s such as g r a s s e s (Jones e t &1. 1977). have been r e s e a r c h e d  i n t h e s e q u e s t r a t i o n o f n i t r o g e n from t h e s o i l  Long-term c o n t r i b u t i o n s by w h i t e c l o v e r , a f t e r by W i l l i a m s  (1959).  He c l a i m e d  t h a t over equal  ploughing, periods  p e r s i s t e n t v a r i e t i e s o f w h i t e c l o v e r had a g r e a t e r e f f e c t on i n c r e a s i n g y i e l d s o f c r o p s f o l l o w i n g i n a r o t a t i o n than the l e s s p e r s i s t e n t v a r i e t i e s . observed t h a t wheat, under h i s c o n d i t i o n s , grown on ground t h a t was  He occupied  by w h i t e c l o v e r f o r t h r e e y e a r s p r e v i o u s l y , y i e l d e d 30% h i g h e r t h a n wheat grown on l a n d o c c u p i e d  by w h i t e c l o v e r f o r o n l y one y e a r .  9 Although  workers have c l a i m e d a 200%  i n c l u d i n g a legume (Dobson and Beaty 1977)  increase i n forage production  by  i n the f o r a g e m i x t u r e , the use  of  w h i t e c l o v e r i n p a s t u r e and f o r a g e seed m i x t u r e s d e c l i n e d i n many c o u n t r i e s i n the e a r l y 1950's ( W i l l i a m s 1969).  On the o t h e r hand, f o r example, the  use  o f i n o r g a n i c n i t r o g e n f e r t i l i z e r doubled i n B r i t a i n , between the y e a r s 1957 1967;  to  t h e r e , the upper f o r a g e y i e l d o f a mixed c l o v e r - r y e g r a s s l e y i s c a . 9000  kgs/ha w h i l e a pure r y e g r a s s l e y , u s i n g up t o 400 u n i t s o f i n o r g a n i c n i t r o g e n , w i l l y i e l d t w i c e t h a t f i g u r e , or c a . 18000 kg/ha o f d r y m a t t e r ( C h e s t n u t t Lowe 1969, The  Cooper 1969,  W i l l i a m s 1969).  reasons f o r the change, to the use o f i n o r g a n i c n i t r o g e n  a r e many and may inexpensive.  and  c o n t i n u e as l o n g as n i t r o g e n o u s  fertilizers  are  fertilizer, relatively  I t i s t o be noted however t h a t a r t i f i c i a l f i x a t i o n o f atmos-  p h e r i c n i t r o g e n i s a h i g h energy consuming  process.  Measurement o f the l e v e l o f n i t r o g e n f i x a t i o n on t o t a l n i t r o g e n f i x e d has t r a d i t i o n a l l y been by the K j e l d a h l method ( B u r r i s 1974).  Although  this  i s an a c c u r a t e means o f t o t a l n i t r o g e n measurement i t i s d e s t r u c t i v e o f plant material. independently  In 1956  b o t h D i l w o r t h and S c h b l l h o r n s i m u l t a n e o u s l y ,  the  and  o b s e r v e d the r e d u c t i o n o f a c e t y l e n e to e t h y l e n e i n the presence  o f a b i o l o g i c a l n i t r o g e n f i x i n g agent ( n i t r o g e n a s e s y s t e m ) ( B u r r i s  1975).  Koch and Evans (1966) p u b l i s h e d the f i r s t work i n the use o f the method f o l l o w e d by p u b l i c a t i o n s by S c h o l l h o r n and B u r r i s (1967) and (1967).  S t e w a r t et  &1.  The method, known as the a c e t y l e n e r e d u c t i o n method, has p r o v e d t o  be b o t h s e n s i t i v e and and the f i e l d .  i n e x p e n s i v e w i t h a p p l i c a t i o n b o t h i n the l a b o r a t o r y  S i n c l a i r et a l . (1967) e v a l u a t e d the t e c h n i q u e  the l i m i t a t i o n s on i t s a c c u r a c y  and  presented  and a p p l i c a t i o n . Overviews o f t h e  technique  have been g i v e n by B e r g e r s e n (1970), B u r r i s (1974) and Hardy et a l . (1968). S e v e r a l p u b l i c a t i o n s e x i s t on the use o f the a c e t y l e n e r e d u c t i o n t e c h n i q u e w i t h v a r i o u s t y p e s o f a s s a y chambers r a n g i n g from 50 ml. s y r i n g e s  by  10 Hardy e t a l . (1968), 21 l i t r e p l a s t i c waste paper b a s k e t s by F i s h b e c k e_£ a l . (1973) to p l a s t i c bags by Lee and  Y o s h i d a (1977).  f u l l y under f i e l d c o n d i t i o n s  (Lee et a l . 1977,  i n remote areas by S t u t z and  Bliss  I t has been used  success-  Vaughn and Jones 1976)  and  (1973).  White c l o v e r has been s u c c e s s f u l l y s t u d i e d by the t e c h n i q u e ( H a l l i d a y and  Pate 1976,  et a l . 1969, i.e.  Low  1977,  S i n c l a i r 1973)  and  the same p l a n t s have been r e p e a t e d l y  the method may The  ing  Haystead and  not  M a s t e r s o n and Murphy 1976,  i n v o l v e d e s t r u c t i o n o f the p l a n t m a t e r i a l  above a u t h o r s have sampled n i t r o g e n a s e  tested. rang-  introduction.  variability.  The  system t o such f a c t o r s as d e f o l i a t i o n o r p l a n t t o p l a n t a u t h o r s c a u t i o n t h a t the i n t e r p r e t a t i o n o f q u a n t i t a t i v e  measurements can be m i s l e a d i n g  unless  adequate c o n t r o l s are employed, t h e s e  isotopes or K j e l d a h l nitrogen Measurement o f e t h y l e n e  production  determinations. has been by t h e use o f gas  chrom-  a t o g r a p h y e i t h e r by d i r e c t i n t r o d u c t i o n from t h e a s s a y chambers o r i n serum v i a l s .  storage  T h i s method of s t o r a g e has proved p r a c t i c a l but l i m i t e d  i n the l e n g t h o f t i m e one  can s t o r e samples b e f o r e a n a l y s i s .  The  publica-  t i o n by M a l l a r d et a l . (1977) o u t l i n e s the c o n s t r u c t i o n and use o f a chromatograph a p p l i c a b l e to f i e l d use. concentrations 2.3 2.3.1  The  r e d u c t i o n t e c h n i q u e has been used to measure q u a l i t a t i v e r e s p o n s e s  by the n i t r o g e n a s e  being  sampled,  a c t i v i t y over periods  from 30 minutes t o t w e n t y - f o u r hours a f t e r a c e t y l e n e  acetylene  Moustafa  Marker  as low as 10 p a r t s per  I t i s capable of d e t e c t i n g  gas ethylene  million.  Genetics  Introduction In the b r e e d i n g and  seed p r o d u c t i o n  to have v i s i b l e p l a n t c h a r a c t e r s or m a t e r i a l s .  of white c l o v e r i t i s very  useful  t h a t can be used t o i d e n t i f y p l a n t  stocks  They can be used f o r a v a r i e t y o f purposes such as the  ident-  11 i f i c a t i o n o f "mother s t o c k s " and t h e f i e l d maintenance  of c e r t i f i e d  In w h i t e c l o v e r t h e r e a r e a number o f v e r y good d i s t i n c t i v e governed by e a s i l y i d e n t i f i a b l e g e n e t i c systems.  stocks.  markers  One o f t h e s e i s t h e  a b i l i t y o f c e r t a i n w h i t e c l o v e r l i n e s t o produce h y d r o c y a n i c a c i d  (HCN) i n  v a r y i n g amounts; d e t e c t i o n o f HCN c a n be u s e f u l l y u n d e r t a k e n by employing the simple p i c r i c a c i d chemical t e s t .  There a r e a l s o a s e r i e s o f l e a f mark-  i n g s which a r e v i s i b l e w i t h t h e eye and which c a n be s i m p l y c l a s s i f i e d . 2.3.2  Cyanogenesis A comprehensive  r e v i e w o f cyanogenic g l y c o s i d e s , w i t h s p e c i a l r e f e r e n c e  to w h i t e c l o v e r , has been p u b l i s h e d by Jones  (1972).  Corkill  (1942 and 1971)  and Daday (1954 a, b, c and 1955) have s t u d i e d s p e c i a l f e a t u r e s o f cyanogenesis i n white clover. "  Cyanogenic g l u c o s i d e s c a n be found i n o v e r s i x t y o f t h e f l o w e r i n g p l a n t  families.  There i s v a r i a t i o n w i t h i n f a m i l i e s , genera and s p e c i e s w i t h  r e s p e c t t o p r e s e n c e o r absence o f c y a n o g e n e s i s . cyanogenic o r a c y n o g e n i c (Jones 1972).  White c l o v e r may be  The presence o f c y a n o g l u c o s i d e s  i n w h i t e c l o v e r was a p p a r e n t l y f i r s t r e p o r t e d by Mirande Cyanogenesis  (1912) .  i n w h i t e c l o v e r o c c u r s when t h e enzyme l i n a m a r a s e a c t s on  ( h y d r o l y s e s ) t h e two g l u c o s i d e s l i n a m a r i n and l o t a u s t r a l i n ; gaseous anic acid i s released  hydrocy-  (Daday 1955, M e l v i l l e and Doak 1940) . The p r o c e s s i s  u s u a l l y a c t i v a t e d by s t r e s s on t h e p l a n t o r by m e c h a n i c a l damage; c o l d temperatures o r mordants such as t o l u e n e o r c h l o r o f o r m a r e a l s o a b l e t o i n i t i a t e t h i s a c t i v i t y (Jones 1972). Cyanogenesis i s governed by two p a i r s o f genes.  One p a i r r e l a t e s t o  the p r e s e n c e o r absence o f t h e c y a n o g l u c o s i d e s ( l o t a u s t r a l i n 80% and l i n a m a r i n 20%) and t h e o t h e r p a i r t o t h e p r e s e n c e and absence o f t h e enzyme linamarase.  I n b o t h p a i r s t h e gene f o r presence i s dominant ( C o r k i l l 1942,  M e l v i l l e and Doak 1940, Pusey 1966) y e t t h e amount o f g l u c o s i d e i s governed  12 p o s s i b l y by the p r e s e n c e o f m o d i f y i n g genes ( C o r k i l l 1942) . Cyanogenesis i s found m a i n l y i n the l e a v e s and p e t i o l e s b u t a p p a r e n t l y i s not a s s o c i a t e d w i t h p l a n t form Jones 1972); i n New  (Atwood and S u l l i v a n 1943, Daday 1955,  Z e a l a n d and the warmer areas o f Europe cyanogenesis i s  a s s o c i a t e d w i t h , but not n e c e s s a r i l y the cause o f , g r e a t e r p l a n t (Bishop and Korn 1969).  When cyanogenic p l a n t s a r e i n j u r e d by f r o s t t h e  enzyme system i s a c t i v a t e d w i t h a subsequent a c i d (Daday 1965).  fitness  I n New  i n t e r n a l release of hydrocyanic  Zealand the most p r o d u c t i v e and p e r s i s t e n t t y p e s  o f w h i t e c l o v e r a r e t h e h i g h e s t i n c y a n o p h o r i c p r o p e r t i e s (Atwood and S u l l i v a n 1943, C o r k i l l 1942, Daday 1955). Because one cannot v i s u a l l y d i s t i n g u i s h c y a n o g e n i c and p l a n t s o r t h e i r seed, t h e New  acyanogenic  Zealand Department o f A g r i c u l t u r e employs the  p i c r i c a c i d t e s t ( G u i g n a r d t e s t ) as one o f the methods used i n i t s s t r a i n c e r t i f i c a t i o n programme (Foy and Hyde 1937).  The f r e q u e n c y o f cyanogenic  p l a n t s i n a p o p u l a t i o n i s governed by g e o g r a p h i c l o c a t i o n and  climate.  Daday (1954 b) r e p o r t e d a decrease i n t h e f r e q u e n c y o f c y a n o g e n i c p l a n t s from the M e d i t e r r a n e a n r e g i o n northwards t o n o r t h e a s t e r n Europe and which i s s t r o n g l y a s s o c i a t e d w i t h the mean J a n u a r y temperatures (Daday 1954  c,  1965).  this  T h i s was a l s o c o n f i r m e d by DeAraujo  (1976) .  Daday a t t r i b u t e d  t o a d e c r e a s e i n the g l u c o s i d e gene f r e q u e n c y and t o a l e s s e r amount, the enzyme gene f r e q u e n c y .  There i s a s l i g h t d i u r n a l and s e a s o n a l v a r i a t i o n i n  the amounts o f h y d r o c y a n i c a c i d r e l e a s e d (Caradus and Evans 1977, 1942).  Corkill  The reasons f o r t h e c l i n a l d i s t r i b u t i o n o f c y a n o g e n e s i s i n w h i t e  c l o v e r may be found i n r e p e l l e n t - d e f e n s i v e mechanisms ( W a l l a c e and M a n s e l l 1975), b u t t h e i n t e r r e l a t i o n s h i p between the p l a n t and i t s u s e r s a r e  complex.  M o l l u s c s have been r e p o r t e d t o consume up t o 17% o f t h e l e a f a r e a o f acyanog e n i c p l a n t s i n w h i t e c l o v e r (Angseesing and A n g s e e s i n g 1973) .  However  13 d i f f e r e n t species of slugs d i f f e r i n t h e i r p r e f e r e n c e f o r cyanogenic p l a n t s (Crawford-Sidebotham 1972) ; f o r example t h e s p e c i e s A g r i o l i m a x  reticulatus  i s not d e t e r r e d i n i t s e a t i n g o f c y a n o g e n i c p l a n t s ( B i s h o p and Korn 1969). White c l o v e r has been r e p u t e d t o cause d e a t h i n c a t t l e y e t sheep r e q u i r e g r e a t e r doses i n o r d e r f o r i t t o be l e t h a l (Todd 1969) .  High l e v e l s of  h y d r o c y a n i c a c i d i n w h i t e c l o v e r a r e o f the o r d e r o f 0.035 p e r c e n t w h i l e the t o x i c l e v e l f o r sheep i s c a . 0.09 p e r c e n t ( B i s h o p and Korn 1969) o r c a . 2.4 mg/kg body weight (Jones 1972). 2.3.3  Leaf Markings L e a f markings i n the genus T r i f o l i u m a r e common (Brewbaker 1955) .  White c l o v e r d i s p l a y s two d i s t i n c t t y p e s , w h i t e and r e d (Cahn and Harper 1976, Carnahan e t a l . 1955, Davies 1963). are  The i n h e r i t a n c e systems f o r b o t h  s i m p l e (Brewbaker 1955, Carnahan e t a j . 1955, D a v i e s 1963) and a r e b o t h  used as v a l u a b l e v i s u a l a i d s i n the i d e n t i f i c a t i o n o f i n d i v i d u a l c l o n e s and strains  (Cahn and Harper 1976 a, b, Carnahan et a l . 1955, C h a r l e s 1968,  C o r k i l l 1971, Harberd 1963) .  White c l o v e r c l o n e s a r e v e r y r a r e l y s e l f -  c o m p a t i b l e ( C o r k i l l 1971); t h e s e l e a f markings make i t r e l a t i v e l y s i m p l e i n m a i n t a i n i n g g e n e t i c p u r i t y and the i d e n t i f i c a t i o n o f p a r e n t a l l i n e s i n the field. There appears t o be a s e a s o n a l e f f e c t i n l e a f mark e x p r e s s i o n .  The  w h i t e marks a r e a t t h e i r s h a r p e s t e x p r e s s i o n between t h e months o f A p r i l and J u l y w i t h t h e l e a s t e x p r e s s i o n from December t o J a n u a r y .  Cahn and  Harper (1976 a, b) observed t h a t sheep p r e f e r p l a n t s w i t h no l e a f markings and  show  markings.  v a r y i n g degrees o f p r e f e r e n c e f o r d i f f e r e n t i n t e n s i t i e s o f A l s o p l a n t s w i t h no l e a f marks a r e s u i t e d t o l o n g p e r i o d s o f  g r a z i n g ( C h a r l e s 1968) and show more r e s i s t a n c e t o s t o l o n r o t by f u n g i (Cahn and Harper 1976 b ) .  14 The make-up o f the w h i t e mark remains  to be c o n c l u s i v e l y r e s o l v e d , but  a m o r p h o l o g i c a l e x p l a n a t i o n appears t o be p r i m a r y .  I t i s r e c o g n i z e d (Brew-  baker 1955, Carnahan e t a l . 1955, E r i t h 1924, Hara 1957) i a t e d w i t h the m e s o p h y l l t i s s u e on t h e upper s u r f a c e .  t h a t i t i s assoc-  The p a l l i s a d e  cells  are l e s s e l o n g a t e d and o r g a n i z e d , y e t appear t o have a g r e a t e r number o f intercellular  spaces.  The r e d markings  on the l e a f , due t o the n a t u r e o f t h e i r  are u s e f u l t o p l a n t b r e e d e r s i n t h e same way markings  c o n t a i n a n t h o c y a n i n (Davies 1963)  inheritance,  as the w h i t e marks.  These r e d  l o c a t e d i n the e p i d e r m a l  tissue  (Carnahan e t a l . 1955, K i r k et a l . 1967); e x p r e s s i o n i s a t i t s g r e a t e s t below  10°F. The g e n e t i c s o f the w h i t e and r e d markings have been s t u d i e d by Brew-  baker  (1955) and by C o r k i l l  (1971) .  The presence o f marks i s  absence.aid the genes c o n t r o l l i n g c o l o u r are independent trolling 2.4.1  dominant to.  o f the genes con-  cyanogenesis. Seed P r o d u c t i o n - G e n e r a l B i o l o g y  An encompassing t r e a t i s e on the management a s p e c t s o f w h i t e c l o v e r , i n the p r o d u c t i o n o f f o r a g e and seed as w e l l as a n i m a l r e l a t e d f a c t o r s f o r Britain, i s available (L°  w e  1969) .  I t contains relevant a r t i c l e s  by those w o r k i n g on v a r i o u s a s p e c t s o f crop management.  authored  Bulletins with  r e l a t i v e i n f o r m a t i o n about w h i t e c l o v e r f o r the farmer i n B r i t a i n , t h e U n i t e d S t a t e s and Canada a r e a v a i l a b l e (Dominion Department o f A g r i c u l t u r e  1941,  U n i t e d S t a t e s Department o f A g r i c u l t u r e 1915, Ware 1925). The s e e d i n g o f f o r a g e s w i t h a s m a l l g r a i n companion crop i s a common p r a c t i c e (Hughes et a l . 1966), w h i t e c l o v e r b e i n g no e x c e p t i o n .  The  choice  o f a g r a i n crop and i t s s e e d i n g r a t e ( s p r i n g wheat, o a t s o r b a r l e y ) r e s t s l a r g e l y on the e d a p h i c , c l i m a t i c , and economic s i t u a t i o n o f t h e a r e a con-  15 cerned.  Smith e t a l . (1954) found,;that under t h e i r c o n d i t i o n s t h e s e e d i n g  r a t e s o f s p r i n g oats, from 24 kgs/ha t o .141. kgs/ha,,, had l i t t l e e f f e c t on t h e establishment  o f a l f a l f a and r e d c l o v e r .  The f a v o u r a b l e  e f f e c t s enjoyed  by t h e s e e d l i n g c l o v e r and a l f a l f a p l a n t s under t h e low s e e d i n g r a t e o f g r a i n was c a n c e l l e d o u t by t h e i n c r e a s e d weed p o p u l a t i o n .  Under heavy seed-  i n g r a t e s o f g r a i n , good weed c o n t r o l was o b t a i n e d b u t m o i s t u r e and s h a d i n g were l i m i t i n g f a c t o r s f o r t h e legume s e e d l i n g s . Seed y i e l d s a r e c l o s e l y r e l a t e d t o t h e number o f i n f l o r e s c e n c e s p e r a c r e and t h e seeds p e r i n f l o r e s c e n c e (Hawkings 1956) .  Floral initiation i n  B r i t a i n , f o r Kent w i l d w h i t e c l o v e r , t a k e s p l a c e when c a . 610 growing degree days have accumulated.  The d a y l e n g t h t h r e s h o l d f o r f l o r a l bud i n i t i a t i o n  i s c a . t h i r t e e n and a h a l f hours (Hagger e t a l . 1963). stage when l i g h t p e n e t r a t i o n  This i s also the -  t o t h e s t o l o n s i s i m p o r t a n t ( Z a l e s k i 1969).  Temperatures a r e a l s o i m p o r t a n t i n d e t e r m i n i n g  f l o w e r i n g and i t s i n t e n s i t y  ( G a r r i s o n and B u l a 1961, Thomas 1962). I t i s common p r a c t i c e i n B r i t a i n t o g r a z e seed p a s t u r e s  or to d e f o l i a t e  i n some o t h e r manner p r i o r t o t h e f l o r a l bud i n i t i a t i o n s t a g e . i s that d e f o l i a t i o n allows l i g h t penetration b r a n c h and p r o v i d e 1963,  The b e l i e f  to the stolons which, i n t u r n ,  a g r e a t e r number o f s i t e s f o r f l o r a l buds (Haggar et. a l .  Z a l e s k i 1969).  The a d d i t i o n o f a n i t r o g e n f e r t i l i z e r  encourages  v e g e t a t i v e growth and c o n s e q u e n t l y reduces t h e number o f f l o w e r heads (Anslow 1962).  I f d e f o l i a t i o n i s d e l a y e d , peduncle l e n g t h w i l l be reduced  and poor p o l l i n a t i o n may r e s u l t (Thomas 1961) . The w o r l d average w h i t e c l o v e r seed y i e l d i s c a . 200 kgs/ha, w i t h a range o f 100 t o 600 kgs/ha. highest y i e l d s per acre  Argentina,  among c o u n t r i e s , appears t o have t h e  (FAO o f t h e U n i t e d N a t i o n s 1961).  Seed  production  i n B r i t a i n has a p o t e n t i a l y i e l d o f c a . 760 kgs/ha (Davies 1969) y e t o n l y  •)'  -  16 a f r a c t i o n of t h i s p o t e n t i a l i s r e a l i z e d  (Haggar et a l . 1963, Hawkins 1960).  H a r v e s t i n g l o s s e s i n t h e form o f s h a t t e r i n g and  seed head l o s s  account  r  for  much o f t h i s l o s s w h i l e s h r i v e l l i n g and i n s e c t damage make up t h e b a l -  ance (Davies 1969, are very dry w i l l  F o r s t e r et a l . 1962).  H a r v e s t i n g when t h e seed heads  r e s u l t i n heavy l o s s e s due to s h a t t e r i n g on t o t h e ground.  The use o f a vacuum-type h a r v e s t e r has g i v e n an 80% r e c o v e r y r a t e o f  seed  (Dexter and McKibben 1945). The age o f a seed c r o p i s i m p o r t a n t i n r e l a t i o n t o i t s seed capacity.  yield  Haggar and Holmes (1963 a) r e p o r t e d t h a t w i l d w h i t e c l o v e r , which  i n t h e f i r s t year o f seed h a r v e s t y i e l d e d 132 kgs/ha, by t h e f i f t h y i e l d e d o n l y 60 kgs/ha o f seed. t h e heads are "brown".  year  H a r v e s t i n g g e n e r a l l y commences when 90% o f  A l a t e harvest i s reputed to g i v e increased y i e l d  w h i l e an e a r l y h a r v e s t r e s u l t s i n a l o w e r i n g o f p e r s i s t e n c e i n f u t u r e gene r a t i o n s (Haggar and Holmes 1963  b).  The c o l o u r i n g o f seeds o f w h i t e c l o v e r  i s not u n i f o r m ; seedsmen p r e f e r seed l o t s c o n s i s t i n g l a r g e l y o f y e l l o w  seeds;  a b r i g h t y e l l o w c o l o u r i s b e l i e v e d to be a r e s u l t o f h a r v e s t i n g c o n d i t i o n s and t o be a s s o c i a t e d w i t h h i g h v i a b i l i t y o f seed  (Haggar and Holmes 1963  b,  Ware 1925). White c l o v e r i s an open p o l l i n a t e d c r o p and honey bees a r e pollinators. seed y i e l d  The presence  o f h i v e s i n a c r o p have g i v e n a 47% i n c r e a s e i n  (Haggar and Holmes 1963  a).  The recommendations f o r numbers o f  h i v e s per a c r e v a r i e s g r e a t l y from c o u n t r y t o c o u n t r y . for  important  e v e r y one h e c t a r e i s recommended (Davies 1969,  In B r i t a i n one  Z a l e s k i 1969)  hive  and i n  Zealand one h i v e i s recommended t o every t h r e e h e c t a r e s (Davies 1969) .  New In  the U n i t e d S t a t e s one h i v e per s i x h e c t a r e s appears to be adequate (Anslow 1962)  but Green (1957) found t h a t one h i v e t o every f o u r h e c t a r e s gave an  a c c e p t a b l e seed s e t .  Pankiw and E l l i o t t  (1959) working on a l s i k e c l o v e r  17 i n t h e Peace R i v e r R e g i o n o f Canada recommended one h i v e t o one h a l f a hectare. Demand f o r a p e r s i s t e n t w h i t e c l o v e r i s h i g h (Haggar and Holmes 1963 b ) ; and management i s an i m p o r t a n t f a c t o r i n p e r s i s t e n c e .  It i s for  t h i s r e a s o n t h a t buyers o f w i l d w h i t e c l o v e r , l o o k i n g f o r seed w i t h h i g h persistence, insist  t h a t t h i s seed be t a k e n from o l d permanent p a s t u r e s  (Haggar and Holmes 1963 b ) .  The tendency f o r seed t o be t a k e n from s h o r t  term l e y s i s r e p u t e d t o be a g u a r a n t e e o f t h e l o s s o f p e r s i s t e n c e . i n t e r e s t i n g t o note t h a t abundant  flowering i s usually associated with a  l a c k o f p e r s i s t e n c e ( D a v i e s 1969, G i b s o n 1957). of  The l a c k i n r e p l a c e m e n t  p h o t o s y n t h e t i c s u r f a c e when p r i m o r d i a become r e p r o d u c t i v e w i l l  i n poor c a r b o h y d r a t e s t o r a g e ( B e i n h a r t 1963). of  It is  result  The l o s s o f o t h e r f e a t u r e s  a s t r a i n a r e a l s o p o s s i b l e when i t i s grown o u t s i d e i t s r e g i o n o f  a d a p t a t i o n ( G a r r i s o n and B u l a 1961). Top growth y i e l d s o f w h i t e c l o v e r grown i n pure stands i n n o r t h e r n l a t i t u d e s range from 2 t o 4.5 t o n s / h a ( A l l e n et a l . 1976, C h e s t n u t t and Lowe 1969, D a v i e s 1969, Ennik 1969).  I n B r i t a i n i t i s customary t o grow,white  c l o v e r f o r seed w i t h a companion g r a s s t h a t i s a l s o h a r v e s t e d f o r seed. For  w h i t e c l o v e r seed p r o d u c t i o n , C h e s t n u t t and Lowe (1969) recommend  t h a t a v a i l a b l e s o i l phosphorus be above 20 p a r t s p e r m i l l i o n and p o t a s s i u m above 200 p a r t s per m i l l i o n .  In B r i t a i n , f e r t i l i z e r a p p l i e d t o m a i n t a i n  t h e s e l e v e l s i s between 224 t o 448 kgs/ha o f superphosphate of  P  e r  h  e c  t  a r e  (40 t o 90 kgs  ) e v e r y two y e a r s and m u r i a t e o f p o t a s h a p p l i e d each  fall  at r a t e s o f 112 t o 224 kgs/ha (67 t o 134 kgs/ha K 0)(Haggar and Holmes 1963 b ) . „In the U n i t e d S t a t e s s i m i l a r recommendations 1977, U n i t e d S t a t e s Department of  a r e made (Caradus and Evans  o f A g r i c u l t u r e 1947).  f e r t i l i z e r to white c l o v e r are j u s t i f i e d  Fall  applications  s i n c e t h e r e i s new n o d a l r o o t  18 growth a t t h a t time w h i c h i s c a p a b l e o f t a k i n g up t h e a v a i l a b l e n u t r i e n t s (Caradus and Evans 1977). Page and Thomson (.1976) l i s t s e v e r a l h e r b i c i d e s t h a t can be s a f e l y a p p l i e d t o w h i t e c l o v e r ; t h e c u r r e n t recommendations f o r c o n d i t i o n s i n B r i t i s h Columbia a r e made a v a i l a b l e t o farmers t h r o u g h t h e f i e l d  crop  recommendations g u i d e C B r i t i s h C o l u m b i a Department o f A g r i c u l t u r e 1978). 2.4.2  P e s t s o f W h i t e C l o v e r Seed Crops White c l o v e r , l i k e a l l o t h e r f o r a g e  p a r a s i t e s from t h e a n i m a l kingdom.  legumes, i s h o s t t o an a r r a y o f  Most a r e n o t - h o s t  s p e c i f i c and w i l l  attack species other than white c l o v e r . The  European c l o v e r seed w e e v i l  (Miccotrogus  picirostris  (Fab.) has  been known t o g i v e a l o s s i n w h i t e c l o v e r seed y i e l d s o f up t o 70% ( S t r i c k l a n d 1956). The  Both l a r v a e and a d u l t s a r e r e s p o n s i b l e f o r economic l o s s e s .  a d u l t s f e e d on t h e d e v e l o p i n g  f l o r e t s and f o r m i n g  l a r v a e f e e d on t h e immature and mature o v u l e s  seed pods, w h i l e t h e  (Swan and Papp 1972).  This  l a r v a l f e e d i n g i s t h e more s e r i o u s damage ( D a v i d s o n and P e a i r s 1966, D e t w i l e r 1923).  Overwintering  t a k e s p l a c e i n t h e a d u l t and egg forms t o g i v e  a r a p i d b u i l d u p o f t h e p a r a s i t e i n one season (Morgan-Jones 1950) . The  adult of the lesser clover l e a f weevil  (Hypera n i g r i r o s t r i s Fab.)  i s known t o cause s e v e r e p l a n t i n j u r y i n y e a r s t h a t a r e d r y e r t h a n n o r m a l . The  adults are mainly  l e a f f e e d e r s , w h i l e t h e l a r v a e f e e d b o t h on t h e l e a v e s  and  f l o w e r buds (Swan and Papp 1972).  Overwintering  a d u l t form around t h e crowns o f t h e c l o v e r o l a n t . y e a r i s normal a l t h o u g h Wiler  takes p l a c e i n the  One g e n e r a t i o n  a  two a r e p o s s i b l e ( D a v i d s o n and P e a i r s 1966, Det-  1923). The  clover root c u r c u l i o (Sitona h i s p i d u l a  Fab.) can be found i n many  p a r t s o f N o r t h A m e r i c a ( D a v i d s o n and P e a i r s 1966, U n i t e d S t a t e s  Department  19  of A g r i c u l t u r e 1947). considered  The  a d u l t s are l e a f f e e d e r s but t h i s damage i s not  t o be o f economic importance (Swann and  Papp 1972).  f e e d on a l l p a r t s o f t h e r o o t system ( r o o t n o d u l e s , tap and i n e a r l y summer and tap r o o t .  Dunn 1961)  larvae  lateral  roots)  l e a v e c h a r a c t e r i s t i c g i r d l i n g s c a r s e s p e c i a l l y on  I n j u r y i s cumulative  the p l a n t (Dickason  The  et. a l .  1958,  and  l e a d s t o t h e e n t r y o f pathogens i n t o  Hill  e t a l . 1969,  1971,  Kilpatrick  r e s u l t i n g i n the l o s s o f p l a n t v i g o u r and p e r s i s t e n c e  et a l . 1968, generations  Hill  et a l . 1971,  the  Pescho 1975,  and  (Dickason  U n d e r h i l l et a l . 1955).  Two  a year are p o s s i b l e ( S t e i n 1970).  Other i n s e c t s o f economic importance to w h i t e c l o v e r come from t h e f a m i l i e s Aphididae,  C u r c u l i o n i d a e , Eurytomidae , C i c a d e l l i d a e , M i r i d a e  Pentatomidae (Davidson and  P e a i r s 1966).  and  B i o l o g i c a l c o n t r o l o f the  i n j u r i o u s i n s e c t p e s t s o f w h i t e c l o v e r i s e x e r c i s e d by the b e e t l e s , t r u e bugs (Homoptera), f l i e s and wasps, f u n g i , v i r u s and b a c t e r i a (Davidson and P e a i r s 1966). Chemical c o n t r o l i s recommended and insect pests 1957,  (Dickason  et a l . 1958,  U n d e r h i l l et a l . 1955)  1968,  i s p r a c t i c a l f o r a l l o f the above N e a l and R a t c l i f f e 1975,  w i t h v a r y i n g degrees o f s u c c e s s .  Turner  P l a n t morph-  o l o g i c a l c h a r a c t e r i s t i c s o f f e r l i m i t e d c o n t r o l or immunity i n some p l a n t s p e c i e s , n o t a b l y a measure o f r e s i s t a n c e i n Medicago s p e c i e s t o t h e weevil  (Hypera p o s t i c a G y l l ) ( L i a n g and  i s apparently  Sorenson 1977).  alfalfa  This resistance  a s s o c i a t e d w i t h pubescence and v a s c u l a r d i f f e r e n c e s .  B i o l o g i c a l c o n t r o l has been e f f e c t i v e l y used i n N o r t h America,, n o t a b l y i n the s t a t e of New  York where 1.9 m i l l i o n a c r e s o f a l f a l f a are  from the a l f a l f a w e e v i l  protected  ( G y r i s c o 1977).  M o l l u s c s can become economic p e s t s i n c l o v e r i n c e r t a i n y e a r s .  The  20 common s l u g ( A g r i o l i m a x f e e d i n g on c l o v e r .  r e t i c u l a t u s ) can cause economic damage by  Chemical c o n t r o l i s p o s s i b l e by the use  a c t u a l metaldehyde i n j e c t e d i n t o the i r r i g a t i o n w a t e r .  leaf  o f two  kgs/ha o f  A natural control i n  w h i t e c l o v e r i s through the r e p e l l i n g f a c t o r o f c y a n o g e n e s i s (Howitt Nematodes (eelworms) can become a p e s t o f w h i t e c l o v e r .  Their  on the r o o t s g i v e r i s e t o poor p l a n t growth and poor n i t r o g e n The  p r i n c i p a l species  1961). feeding  fixation.  are the r o o t l e s i o n nematode ( P r a t y l e n c h u s  sp.)  ( W i l l i s and Thompson 1977), c l o v e r r o o t nematodes ( H e t e r o d e r a t r i f o l i i Meloidogyne h a p l a ) and and Thompson 1977,  the stem eelworm (Tylenchus sp.)  Yeates 1976,  Yeates et a l . 1977).  and  (Goodey 1950,  Willis  Although chemical  c o n t r o l i s i n c r e a s i n g i n i t s p r a c t i c a l a p p l i c a t i o n on a f i e l d s c a l e , crop rotation i s s t i l l 2.4.3  the recommended method (Yeates et a l . 1976).  D i s e a s e s o f White C l o v e r Seed Crops More t h a n t h i r t y d i s e a s e s  f o r a g e and "Clover and  i n w h i t e c l o v e r l i m i t the p r o d u c t i o n  seed f o r t h i s crop ( U n i t e d S t a t e s Department o f A g r i c u l t u r e 1947) .  s i c k n e s s " , a c a t c h a l l term, i s o f a p r a c t i c a l c o n c e r n t o many growers  farmers (Board o f A g r i c u l t u r e and  ment o f A g r i c u l t u r e 1924).  i n p l a n t y i e l d and  F i s h e r i e s 1913,  United States  s t a n d d e n s i t y or the poor e s t a b l i s h m e n t o f a c l o v e r crop  f o r the d e c l i n e have been put  forward.  Several  sug-  These u s u a l l y i n v o l v e a  c o m b i n a t i o n o f c l o v e r r o t ( S c l e r o t i n i a t r i f o l i o r u m ) and stem eelworm The  the  U s u a l l y the symptoms are e i t h e r a d e c l i n e  when r e s e e d e d w i t h i n f o u r y e a r s o f a p r e c e e d i n g c l o v e r c r o p .  Weston 1950) .  Depart-  I t i n v o l v e s a l l the c u l t i v a t e d c l o v e r s y e t  causes remain obscure (Mann 1950) .  gestions  of  (Dillon  v a r i e t y from Denmark, " P a j b e r g M i l k a " , i s r e s i s t a n t t o  c l o v e r r o t ( A l d r i c h 1969) .  O'Rourke (1969) c o n s i d e r s  t h a t r o o t r o t complex  o f w h i t e c l o v e r t o be the most l i m i t i n g f a c t o r i n the e s t a b l i s h m e n t , t i o n and p e r s i s t e n c e  d f t h i s crop i n I r e l a n d .  He  considers  that  the  produc-  21 u n a c c o u n t a b l e f a i l u r e i n c l o v e r p e r s i s t e n c e can be a t t r i b u t e d t o two Fusarium s p e c i e s t h a t a r e r e s i d e n t i n t h e s o i l . i s considered  Damage by t h e s e f u n g i  t o o c c u r o n l y when t h e p l a n t i s s u b j e c t e d t o s t r e s s i n s  form; a t no o t h e r time does damage o c c u r .  22  3.  DESCRIPTION OF STUDY AREAS  3.1.1  Creston The C r e s t o n v a l l e y i s s i t u a t e d i n s o u t h e a s t e r n B r i t i s h Columbia and  i s a p p r o x i m a t e l y 806 k i l o m e t e r s due east o f Vancouver.  The a r e a o c c u r s i n  the P u r c e l l T r e n c h s o u t h o f Kootenay l a k e a t e l e v a t i o n s between 530 t o 760 meters above sea l e v e l .  The a g r i c u l t u r a l p a r t o f t h e v a l l e y runs i n a  s o u t h - e a s t t o n o r t h - w e s t d i r e c t i o n , i s about 24 k i l o m e t e r s l o n g and i s 6 to 10 k i l o m e t e r s wide. hectares.  I t c o m p r i s e s a t o t a l a r a b l e h e c t a r a g e o f 18,802  The C r e s t o n f l a t s on which w h i t e c l o v e r seed p r o d u c t i o n t a k e s  p l a c e a r e a l l u v i u m and comprise a t o t a l a r a b l e h e c t a r a g e o f 9,120 h e c t a r e s (Wittneben and Sprout 1971). The c l i m a t e o f t h e C r e s t o n a r e a f a l l s i n t o Kbppen's w o r l d c l a s s i f i c a t i o n as Humid C o n t i n e n t a l w i t h warm summers (Department o f Mines T e c h n i c a l Surveys 1957).  The C r e s t o n f l a t s  and  r e c e i v e about 2800 growing  degree days a y e a r and about 120 f r o s t f r e e days w i t h 175 t o 200 m i l l i m e t e r s of p r e c i p i t a t i o n during that period. meters.  Annual s n o w f a l l i s about 1400  The c l i m a t i c d a t a i s p r e s e n t e d i n F i g u r e 3.1.1  Department  o f A g r i c u l t u r e 1974; Connor 1949).  milli-  ( B r i t i s h Columbia  S i x f i e l d s f o r s t u d y were  chosen f o r t h e i r g e o g r a p h i c p o s i t i o n ; a l l f i e l d s chosen had a companion c r o p seeded w i t h the w h i t e c l o v e r ; g e n e r a l management i n a l l f i e l d s was c o n s i d e r e d t o be average o r b e t t e r t h a n average.  chosen  The f i e l d s were  l o c a t e d on t h e a l l u v i a l f l a t s w i t h a d i s t a n c e o f 10 k i l o m e t e r s between the southernmost and northernmost f i e l d . i n between.  The r e m a i n i n g f o u r f i e l d s o c c u r r e d  Four f i x e d but r o u g h l y randomly chosen s a m p l i n g a r e a s were  l o c a t e d w i t h i n each f i e l d .  Photographs o f each f i e l d and sampling a r e a  a r e found i n F i g u r e s 3.1.2, 3.1.3, 3.1.4  and 3.1.5.  F i g u r e .3.1.1  Average t e m p e r a t u r e , p r e c i p i t a t i o n , f r o s t f r e e p e r i o d a t C r e s t o n , B.C.  2.3 ( r  Average Temperatures and Precipitation at Creston by Month  Temp. °F  °C  80 2 7 r -  Maximum Avg. frost free p e r i o d  .Minimum  ^  Precipitation 70  21  60  16  50  10  40  4  1  »-  i  Ption. Inches  8 30  -1  A  7 6  20  - 7  5 4 3  10 - 1 2  0 -18  1  Jan  F  I M  2 1  A  M  J  J  Month  A  S  O  N  D  24 3.1.2  Comment on F i e l d Management The i n d i v i d u a l farm f i e l d i s t h e r e s u l t o f a c o m p l e x i t y o f f a c t o r s ,  b i o l o g i c a l , economic and human.  O n l y a few o f t h e c u r r e n t management  f a c t o r s , over which t h e p r o d u c e r may have some c o n t r o l and which may be c o n s i d e r e d t o have r e l e v a n c e t o seed p r o d u c t i o n , a r e r e c o r d e d f o r t h e ' i n d i v i d u a l f i e l d s s e l e c t e d f o r t h i s study. the  In the i n t e r e s t s o f b r e v i t y  management r e c o r d i s by p h r a s e and i n c l u d e s a few o c c a s i o n a l o b s e r v a -  t i o n s on t h e development o f t h e seed c r o p . F i e l d 1: This f i e l d  "Wyndell s o u t h " . i s l o c a t e d a t t h e s o u t h end o f t h e v a l l e y a d j a c e n t t o t h e  A g r i c u l t u r e Canada Research Sub S t a t i o n and b e l o n g s t o Wyndell Farms L t d . F i e l d acreage - 65 a c r e s (26 h e c t a r e s ) . 1976 - B a r l e y seeded a t 90 l b s p e r a c r e (100 kgs/ha)  with  w h i t e c l o v e r underseeded a t 3 l b s p e r a c r e (3.4 k g s / h a ) . - F e r t i l i z e r a p p l i e d - 22 l b s (25 kgs) N; 66 l b s (74 kgs) P 0 ; 66 l b s (74 kgs) K 0 as 8-24-24 a t s e e d i n g t i m e . 2  5  2  1977 - May 1 5 t h t o 20th - 2 p i n t s p e r a c r e (2.3 l i / h a ) MCPB (Tropotox) f o r Canada t h i s t l e  ( C i r s i u m Arvense (L.)  Scop.) and p e r e n n i a l s o w t h i s t l e (Sonchus a r v e n s i s ( L . ) ) control  ( F r a n k t o n 1955).  - June 7 t h t o June 30th - Bloom 30% t o 100% r e s p e c t i v e l y . - 48 h i v e s o f bees i n t r o d u c e d (1 h i v e t o 1.4 a c r e s , 0.6 h e c t a r e s ) . - June 22nd - 2 p i n t s p e r a c r e (2.3 l i / h a ) M a l a t h i o n f o r c l o v e r seed w e e v i l  control.  - J u l y 2nd - Bloom "browning". - August - swathed, combined  and mouldboard  ploughed.  - C l o v e r seed y i e l d 400 l b s / a c a f t e r c l e a n i n g  (448 k g s / h a ) .  26 F i e l d 2:  "Eastman".  T h i s f i e l d i s l o c a t e d i n t h e m i d d l e o f t h e v a l l e y and b e l o n g s t o E a s t man Farms L t d . 1976  F i e l d acreage - 55 a c r e s  (22 h e c t a r e s ) .  - S p r i n g wheat seeded a t 90 l b s / a c (100 kgs/ha) and c l o v e r underseeded a t 3 l b s / a c (3.4 k g s / h a ) . - F e r t i l i z e r a p p l i e d - 6 l b s (6.7 kgs) N; 20 l b s (22.4 kgs) P 0 ; 20 l b s (22.4 2  5  kgs)  K 0 as 8-24-24 a t seeding 2  time per acre.  - June 5 t h - 10 oz/ac (685 g/ha) o f 2,4-D f o r g e n e r a l weed c o n t r o l - October 10th - 6 oz/ac (411 g/ha) MCPA f o r g e n e r a l weed c o n t r o l . 1977  - May 27th - 3 p i n t s / a c (3.4 l i / h a ) MCPB (Tropotox) f o r dandel i o n s , Canada t h i s t l e and p e r e n n i a l s o w t h i s t l e c o n t r o l . - June 1 s t t o J u l y 2nd - Bloom 30% t o 100%. - 45 h i v e s o f bees i n t r o d u c e d  (1 h i v e t o 1.2 a c r e s , 0.5 h a ) .  - June 22nd - 1 l b / a c (1.1 kgs/ha) M a l a t h i o n  f o r c l o v e r seed  weevil c o n t r o l . - August 20th - swathed, combined and c h i s e l ploughed, - . c l o v e r seed y i e l d 400 l b s / a c a f t e r c l e a n i n g F i e l d s 3 and 4:  (448 k g s / h a ) .  "Huscroft"  These f i e l d s a r e l o c a t e d on t h e e a s t e r n s i d e o f t h e v a l l e y south o f the v i l l a g e o f Wyndell and belong t o H u s c r o f t - 80 a c r e s 1976  Bros. Farm.  F i e l d acreage  (32 h e c t a r e s ) . - May 14th - F i e l d 3 ( e a s t e r n s e c t i o n ) - B a r l e y seeded; F i e l d "4" (west s e c t i o n ) S p r i n g wheat seeded.  On b o t h  the c e r e a l was seeded a t 90 l b s / a c r e (100 kgs/ha) and c l o v e r underseeded a t 4 l b s / a c r e (4.5 k g s / h a ) . - F e r t i l i z e r a p p l i e d - 11 l b s (12.3 P 0 ; 39 l b s (43.7 2  5  kgs)  kgs) N; 22 l b s (24.6 kgs)  K 0 ; 2 l b s (2.2 kgs) 2  17-34-0 and 0-0-60 a t seeding  time.  o f Boron; as  Figure 3.1.4 A e r i a l photograph of f i e l d s 3,  h and 5-  28 1977  - May 13th - F i e l d "4" 2.25 p i n t s p e r a c r e  (2.6 l i / h a ) MCPB  (Tropotox) f o r p e r e n n i a l s o w t h i s t l e and d a n d e l i o n c o n t r o l . - June 7 t h t o June 22nd - 40% t o 100% Bloom. - 64 h i v e s o f bees i n t r o d u c e d  (1 h i v e t o 1.3 a c r e s , 0.5 h e c t a r e s ) .  - June 22nd - 1.5 p i n t s (1.7 l i / h a ) M a l a t h i o n  f o r c l o v e r seed  weevil c o n t r o l . - J u l y 2nd t o J u l y 15th - p e r e n n i a l s o w t h i s t l e d e n s i t y  high  i n places. - August - swathed, combined and c h i s e l ploughed; seed y i e l d 400 l b s / a c a f t e r c l e a n i n g  (448 k g s / h a ) .  F i e l d 5: O g i l v i e . T h i s f i e l d i s l o c a t e d d i a g o n a l l y a c r o s s t h e road north- o f H u s c r o f t and b e l o n g s t o O g i l v i e farms. 1976  F i e l d acreage - 50 a c r e s  field  (20 h e c t a r e s ) .  - S p r i n g wheat, seeded a t 90 l b s / a c r e (100 kgs/ha) and c l o v e r underseeded.  .  - F e r t i l i z e r 56 l b s (62.7 l b s (22.4  kgs)  \ kgs) N; 96 l b s (107.5 kgs)  P 0 ;'20  k 0 as 11-48-0; 34-0-0 and 0-0-60 a t s e e d i n g 2  time per acre. - Avadex BW ( t r i a l l a t e ) and MCPB (Tropotox) f o r w i l d o a t s and g e n e r a l weed c o n t r o l . 1977  - May - heavy i n f e s t a t i o n o f d a n d e l i o n s ,  perennial sowthistle  and Canada t h i s t l e ; no weed c o n t r o l u n d e r t a k e n . - June 7 t o June 22nd - 30% t o 100% bloom. - 40 h i v e s o f bees i n t r o d u c e d  (1 h i v e t o 1.3 a c r e s , 0.5 h e c t a r e s ) .  - June 22nd - 2 p i n t s (2.3 l i / h a ) M a l a t h i o n  f o r c l o v e r seed  weevil c o n t r o l . - J u l y 2nd - Blooms "browning". - August - swathed and combined; c l o v e r seed y i e l d 240 l b s / a c r e a f t e r c l e a n i n g (269 k g s / h a ) .  29 - October - c h i s e l ploughed. F i e l d 6:  "Wyndell  North".  T h i s f i e l d i s l o c a t e d a t t h e n o r t h end o f t h e v a l l e y about one m i l e n o r t h - w e s t o f t h e v i l l a g e o f Wyndell and b e l o n g s t o Wyndell Farms. acreage - 60 a c r e s 1976  Field  (24 h e c t a r e s ) .  - B a r l e y seeded a t 90 l b s / a c r e (100 kgs/ha) and c l o v e r underseeded a t 3 l b s / a c  (3.4 k g s / h a ) .  - F e r t i l i z e r a p p l i e d - 12 l b s (13.4 kgs) N; 36 l b s (40.3 kgs) P 0 ; 36 l b s (40.3 kgs K 0 as 8-24-24 a t seeding 2  1977  5  2  - May 1 5 t h t o 20th - 2 p i n t s p e r a c r e  time per acre.  (2.3 l i / h a ) _ MCPB (Tropotox)  f o r Canada t h i s t l e and p e r e n n i a l s o w t h i s t l e c o n t r o l . - June 7 t h t o J u l y 2nd - 10% t o 100% Bloom. - 44 h i v e s o f bees i n t r o d u c e d  (1 h i v e t o 1.4 a c r e s , 0.6 h e c t a r e s ) .  - June 22nd - 2 p i n t s / a c r e (2.3 l i / h a ) M a l a t h i o n  f o r c l o v e r seed  weevil c o n t r o l . - J u l y 2nd - heavy i n f e s t a t i o n o f p e r e n n i a l s o w t h i s t l e cont r o l l e d by c l i p p i n g . - August t o September - swathed, combined and mouldboard ploughed. - C l o v e r seed y i e l d 450 l b s / a c r e (500 k g s / h a ) . 3.1.3  S o i l S e r i e s by F i e l d s  The  s o i l s o f t h e C r e s t o n V a l l e y a r e a where v i r t u a l l y a l l o f t h e w h i t e  c l o v e r i s grown a r e developed on r e c l a i m e d  (dyked) a l l u v i u m d e p o s i t e d i n  r e c e n t m i l l e n n i a by t h e Kootenay R i v e r as i t debouched i n t o Kootenay Lake; o l d c h a n n e l l i n g and v a r i a b l e d e p o s i t i o n a l p a t t e r n i n g i s s t i l l v i s i b l e i n the g e n e r a l l y f l a t t e r r a i n ; some m o d i f i c a t i o n by p l o u g h i n g , d r a i n a g e i s t o be seen i n t h e s o i l p r o f i l e s .  " f l o a t i n g " and  To some degree s o i l  variability  i s r e f l e c t e d i n t h e s o i l s r e c o r d by f i e l d and s o i l s e r i e s d e s c r i p t i o n g i v e n below.  30  31 Soil Series (Wittneb.en and Sprout Field 1 Field 2  (65 (30 (55 (22  acres) A l l sampling hectares) acres) A l l sampling hectares)  1971)  areas  Benny  areas  Kuskanook 7/10 Buckworth 2/10  F i e l d 3 § 4 (80 a c r e s ) A l l sampling (32 h e c t a r e s )  areas  Kuskanook 7/10 Buckworth 3/10  Field 5  (areas w i t h  Buckworth  early maturity)  Kuskanook 2/10  (50 a c r e s ) Sampling a r e a 1 (20 hectares)Sampling areas 2 5 3  Rykerts  (60 a c r e s ) Sampling areas 1 (24 h e c t a r e s )  Buckworth Nicks  Sampling a r e a 4 Field 6  8/10  2  Benny 7/10 R y k e r s t 3/10  Sampling areas 3 § 4  Nicks  8/10  Kuskanook 2/10  Soil Series Description Benny  Great s o i l group  Regosol  Sub group  Gleyed o r t h i c r e g o s o l  Parent m a t e r i a l  Alluvium  Texture  F i n e sandy loam  Drainage  Imperfect  pH  7.9 m o d e r a t e l y  Calcium  25 m.e. p e r 100 gms h i g h  Magnesium  1.35 m.e.  alkaline  p e r 100 gms. Med.  32 Potassium White c l o v e r  Buckworth  suitability  High  Great s o i l group  Gleysol  Sub group  Carbonated rego g l e y s o l  Parent m a t e r i a l  Alluvium  Texture  Very f i n e sandy loam  Drainage  Poor  pH  7.9 m o d e r a t e l y a l k a l i n e  White c l o v e r  Kuskanook  0.13 m.e. p e r 100 gms.  suitability  Medium  Great s o i l group  Gleysol  Sub group  Carbonated o r t h i c g l e y s o l  Parent m a t e r i a l  Alluvium  Texture  S i l t y c l a y loam  Drainage  Moderately t o poorly  pH  8.0 m o d e r a t e l y a l k a l i n e  Nitrogen  0.195% (low)  Phosphorous  10.5 ppm (low-med)  Potassium  0.1 me/100 gms ,(L)  Calcium  27.55 me/100 gms  Magnesium  1.76 me/100 gms (med)  White c l o v e r  suitability  drained  Medium  Nicks  Great s o i l group  Gleysol  ( F i e l d 5, 6)  Sub group  Low humic e l u v i a t e d g l e y s o l  Parent m a t e r i a l  Alluvium  33 Texture  C l a y loam  Drainage  Poor t o m o d e r a t e l y poor  pH  7.8 ( m i l d l y  Nitrogen  0.162% (low)  Phosphorous  4,2 ppm (low)  Potassium  0.11 me/100 gms t  Calcium  14.88 me/100 gms  Magnesium  3.01 me/100 gms (med)  White c l o v e r  suitability  group  alkaline)  Low  Regosol  Rykerts  Great s o i l  ( F i e l d 5, 6)  Sub group  Gleyed o r t h i c Regosol ( C a l )  Parent  Alluvium  material  Texture  F i n e loamy sand  Drainage  Imperfect  pH  7.5 m i l d l y a l k a l i n e  Nitrogen  0.133% (low)  Phosphorous  5 ppm (low)  Potassium  0.07 me/100 gms  Calcium  18.73 me/100 gms  Magnesium  0.92 me/100 gms  White c l o v e r  suitability  Medium t o h i g h  34 3.2.1  UBC  Study  Area  The a r e a used f o r t h e s t u d y o f w h i t e c l o v e r was U n i v e r s i t y o f B.C. of  a t P o i n t Grey.  l o c a t e d a t the  The a r e a i s s i t u a t e d on the west c o a s t  t h e Lower M a i n l a n d and e x p e r i e n c e s a humid, mesothermal c l i m a t e , m a r i n e  west c o a s t as found i n KQppen's World C l a s s i f i c a t i o n (Department o f Mines and T e c h n i c a l S u r v e y s , 1957).  The average c l i m a t i c d a t a a r e p r e s e n t e d  g r a p h i c a l l y i n F i g u r e 3.2.1.  The average f r o s t - f r e e p e r i o d i s a p p r o x i m a t e l y  260 days, w i t h an approximate  p r e c i p i t a t i o n i n the growing  mm  (B.C. Department o f A g r i c u l t u r e 1974; Connor 1949).  u p l a n d s o i l developed  on g l a c i a l m a t e r i a l .  w i t h an a c i d s o i l r e a c t i o n o f about pH 5.0  The  season o f  The  sub-drainage  soil  275  i s an  is restricted,  ( K e l l y and S p i l s b u r y 1939).  a r e a i s a p p r o x i m a t e l y 107 meters above sea l e v e l and t h e topography  is  undulating.  as  The a r e a e x p e r i e n c e s t h e same number o f d a y l i g h t hours  The  does C r e s t o n . ' The l a n d used f o r t h e t r i a l s was p r e v i o u s l y uncropped except f o r f a l l r y e and A u s t r i a n w i n t e r peas grown as a green manure c r o p over t h e w i n t e r . Barnyard manure was  a p p l i e d i n t h e s p r i n g and t h i s t o g e t h e r w i t h the  manure was ploughed  under i n t h e s p r i n g o f 1977.  The a r e a was  green  harrowed,  " f l o a t e d " , and r o c k s were removed p r i o r t o p l a n t i n g o f e x p e r i m e n t a l m a t e r i a l .  Figure  3.2.1  Average t e m p e r a t u r e , p r e c i p i t a t i o n , and f r o s t p e r i o d a t t h e U n i v e r s i t y o f B r i t i s h Columbia.  AVERAGE TEMPS. AND PRECIPITATION  Temp. o  o  F  C  80  271  70  21  60  16  50  10  40  4  AT U.B.C.  BY M O N T H • Maximum • Minimum Precipitation  Av. Frost F r e e  Period  Ptioa I Inch. 30  8  -1  7 6 20  -7 5 4  10  3  -12  2 1 0  -18  Jan  F  M  A  M  J  J  y  Month  A  S  O  N  Dec  36  4.  OBSERVATIONS AND EXPERIMENTS A.  F o r Creston-based  Studies  S e l e c t i o n o f t h e f i e l d s and l o c a t i o n s took p l a c e on t h e 1 1 t h o f May, 1977. The f i e l d s c o n s t i t u t e r o u g h l y a n o r t h - s o u t h t r a n s e c t o f t h e v a l l e y ; s i t e s w i t h i n f i e l d s were l o c a t e d a t random b u t c l u s t e r i n g was a v o i d e d . 4.1  Sampling  f o r Insects  No one method of. a s s e s s i n g i n s e c t k i n d and abundance i s w i t h o u t d i f f i c u l t y and c r i t i c i s m .  A c c o r d i n g l y , s e v e r a l approaches t o assessment and  m o n i t o r i n g were u n d e r t a k e n w i t h t h e a s s i s t a n c e o f a s t u d e n t r e s i d e n t i n C r e s t o n employed by t h e B.C. M i n i s t r y o f A g r i c u l t u r e . 4.1.1  Sweeps  4.1.1.1  M a t e r i a l s and Methods  Three sweeps i n each l o c a t i o n i n each f i e l d on each s e p a r a t e d a t e were made w i t h a 15 i n c h n e t . bee a c t i v i t y .  Sweeping took p l a c e p r i o r t o 08:00 hours t o a v o i d  Samples were p l a c e d i n p l a s t i c bags and f r o z e n .  The sweeps  took p l a c e on t h e f o l l o w i n g d a t e s i n t h e summer o f 1977: May 1 9 t h , June 7 t h , June 1 5 t h , June 20th, June 24th, June 2 9 t h , J u l y 8 t h and J u l y 1 5 t h .  The  average numbers o f w e e v i l s c o l l e c t e d f o r each f i e l d were c o n v e r t e d t o 20 sweeps p e r f i e l d . 4.1.1.2  O b s e r v a t i o n s and R e s u l t s  The r e s u l t s o f t h e sweeps a r e r e p r e s e n t e d by F i g . 4.1.1.  The most  s t r i k i n g feature i s that there are three species o f weevils present i n a l l six fields weevil).  ( c l o v e r r o o t c u r c u l i o , c l o v e r seed w e e v i l , l e s s e r c l o v e r l e a f There appears l i t t l e o v e r l a p between t h e a d u l t s among s p e c i e s ,  however, l a r v a e o f t h e c l o v e r r o o t c u r c u l i o a r e i n evidence i n June.  Table  4.1.1 Average number o f w e e v i l s c o l l e c t e d by sweeping the f o l i a g e a t C r e s t o n ; numbers p r e s e n t e d  Field  Species  May 19  1-  A B C  14  A B C  3  June 7  f o r each s p e c i e s by f i e l d and date  June 15  Date June 20 June 24  June 29  July 8  0.8 0.5  0.4  3.8 1  2.1 1.5  2.9 3  0.4 1  0.5 5  7.5  6.3  15.4  A B C  1 6.0  14.2  6.0  0.4  A B C  3 5.4 1  0.5 15.4  0.5 17.9  1.7  3 4.6  1 3.5  7 4.6  4 1 .3 0.5  1  A B C  6  A B C  7  Weevil  2.5  2.5 1  1.7  0.8 0.5  1  2  species  -  Clover root curculio - A C l o v e r seed w e e v i l - B Lesser clover l e a f weevil  -  C  J u l y 15  0.4 11  0.8 10  0.8 18  0.8 10  5.0 63  22  Figure  4.1.1  W e e v i l s c o l l e c t e d "by means o f sweeping t h e f o l i a g e i n s i x f i e l d s i n t h e C r e s t o n v a l l e y . The number o f w e e v i l s i s t h e average o f f o u r s i t e s i n each f i e l d c o n v e r t e d t o number o f w e e v i l s f o r twenty sweeps. C o l l e c t i o n s were made on e i g h t dates with, a m a l a t h i o n s p r a y c o n t r o l a p p l i e d on t h e 22nd and 23rd day o f June.  3 8 tr. Creston: Sweeps Field 1  Clover root curculio i Clover seed weevil • Lesser clover leaf weevil 1  S3 c. Creston: Sweeps  Clover root curculio I Clover seed weevil * Lesser clover leaf weevil  Field 4  i(H  5H  19  1_L  1 15  20  24  29  8  20  24  29  8  20  24  29  15 =  Field 5 10-4 >  <a <u  i  E z 0  19  i  !  il  JL-5.  15 i  Field 6  5H  i  Date: I I  MAY  19  15  JUNE  i  i  i  '  8  JULY  15  ,  I I i  39  A d u l t s o f the t h r e e s p e c i e s o f w e e v i l e s s e n t i a l l y occur on s e p a r a t e o c c a s i o n s w i t h i n the sampled growing season.  three  L a r v a e o f the  c l o v e r r o o t c u r c u l i o were observed t o o c c u r i n June, w h i l e the a d u l t s from t h e s e l a r v a e , emerged from pupation-. at the end o f J u l y , as sampled by p i t f a l l t r a p s .  An a e r i a l spray c o n t r o l was  a p p l i e d on the 22nd  23rd o f June u s i n g M a l a t h i o n t o c o n t r o l the c l o v e r seed w e e v i l .  Control  appeared e f f e c t i v e i n r e d u c i n g the c l o v e r seed w e e v i l p o p u l a t i o n . p r e s e n c e o f t h e c l o v e r seed w e e v i l e a r l y i n June i n a l l f i e l d s  and  The  should  w a r r a n t c o n c e r n when t h e i r f e e d i n g h a b i t s a r e taken i n t o c o n s i d e r a t i o n . 4.1.1.3  Discussion  Sweeping appears t o be an e f f e c t i v e method o f assessment o f w e e v i l activity.  The  s t a r t i n g d a t e o f May  been a t l e a s t May  the 1 s t .  19th was  too l a t e and  s h o u l d have  T h i s would have g i v e n a b e t t e r i d e a o f  peak p o p u l a t i o n o f the c l o v e r r o o t c u r c u l i o .  Also, a higher  the  frequency  o f sweeps per week would have been d e s i r a b l e so t h a t t r u e peaks o f a d u l t w e e v i l a c t i v i t y c o u l d have been o b t a i n e d . o f a, more e f f e c t i v e c o n t r o l programme.  T h i s would f a c i l i t a t e  The  sweeping s h o u l d a l s o  planning take  i n t o account l e a f f e e d e r s r a t h e r t h a n j u s t those on the f l o w e r p a r t s . 4.1.2  S t i c k y Traps  4.1.2.1  M a t e r i a l s and Methods  Three f i e l d s were chosen as s i t e s .  These were f i e l d s 1, 5 and  gave a rough r e p r e s e n t a t i o n o f the study a r e a from south to n o r t h . o f the t h r e e f i e l d s , two  6.  This  In each  l o c a t i o n s f o r t r a p s were chosen a t random from f o u r  l o c a t i o n s chosen e a r l i e r f o r o t h e r purposes. 9 i n c h by 11 i n c h y e l l o w r a i l r o a d b o a r d .  The  s t i c k y traps consisted of  "Stickum"  was  a p p l i e d t o one  side  40 o f t h e board on s i t e . t h r e e f e e t ..off  Two boards were p l a c e d on a s t a k e w i t h t h e i r t r a p s  t h e ground.  One board f a c e d s o u t h and one f a c e d n o r t h .  C o l l e c t i o n d a t e s and p e r i o d s o f exposure were: 8th,  J u l y 1 9 t h and J u l y 27th.  June 7 t h , June 2 4 t h , J u l y  When boards were c o l l e c t e d t h e y were  wrapped i n Saran wrap and p l a c e d i n t h e f r e e z e r . Assessment o f t h e c o l l e c t i o n s was based on a v i s u a l e s t i m a t i o n o n l y s i n c e i t was v i r t u a l l y i m p o s s i b l e t o c l a s s i f y a l l organisms t o genus, and to make an a c c u r a t e count.  I t was then d e c i d e d t o make o n l y a v i s u a l  assessment and t o c l a s s i f y t o o r d e r o n l y .  However, Hymenopterans were  counted and r e p r e s e n t e d as average numbers p e r f i e l d .  Thysanopteran  numbers were noted on a s c a l e o f t h r e e , v i z (a) few ( 1 0 ) , (b) many ( 2 0 ) , and (c) v e r y many (30). isms were 4.1.2.2 The  Absence o f a b a r on t h e graph i n d i c a t e s t h a t no o r g a n -  observed. Observations  and R e s u l t s  r e s u l t s o f t h e s t i c k y t r a p s a r e found i n F i g u r e 4.1.2.1.  Organisms  from t h e o r d e r s Hymenoptera and T h y s a n o p t e r a o c c u r r e d i n n o t i c e a b l e numbers. Other organisms which o c c u r r e d s p o r a d i c a l l y were: podamia s p . ) , s t i n k bugs ( P e n t a t o m i d a e ) , ( C u r c u l i o n i d a e ) and f l i e s  (Diptera).  l a d y b i r d b e e t l e (Hip-  butterflies  (Lepidoptera), weevils  The o r d e r Hymenoptera encompasses  s e v e r a l wasps t h a t a r e known t o be p a r a s i t i c and a r e c o n s i d e r e d t o g i v e some biological control.  There i s an i n c r e a s e i n t h e wasp p o p u l a t i o n up t o June  24th and a drop a f t e r t h e s p r a y a p p l i e d on June 22nd. e v i d e n t a month l a t e r .  T h r i p s were p r e s e n t  i n June i n f i e l d  reappeared i n l a r g e amounts i n t h e l a t t e r h a l f o f J u l y . and Thysanopterans a r e p a r a s i t i c .  A r a p i d b u i l d u p was 5 o n l y and t h e n  Not a l l Hymenopterans  41  Table  4.1.2  Average number o f organisms i n groups c o l l e c t e d by means o f s t i c k y t r a p s a t C r e s t o n ; numbers p r e s e n t e d f o r each group by f i e l d and d a t e . Field  Group  1  H T  5  H T  6  H T  June 7  Date July 8  June 24 3  1 10 2.5  Hymenoptera  H  Thysanoptera  T  J u l y 19  J u l y 27  24 20  14 30  15  2  16 20  36 30  13  2  5  25 30  T a b l e 4.1.3.3 Averag e number o f organisms i n groups c o l l e c t e d by means o f pit  f a l l t r a p s a t C r e s t o n ; numbers p r e s e n t e d f o r each group by f i e l d and d a t e . Date  Field  Group  June 8  June 28  J u l y 15  J u l y 27  1  B S D  31 16 5  30 8 2  32 54  50 41 15  5  B S D  49 35 4  71 60 7  43 53 4  53 24 3  6  B S D  46 5 1  46 33 3  62 15 4  21 15 7  B S D  42  F i g u r e 4.1.2.1 Assessment o f s t i c k y t r a p s a t C r e s t o n ; l o c a t e d i n f i e l d s 1, 5 and 6, w i t h two l o c a t i o n s i n each f i e l d and two b o a r d s a t each l o c a t i o n . Graph d a t e  Sampling p e r i o d  June 7 t h  May 30th t o June 7 t h  June 24th  June 7 t h t o June 24th  July 8th  June 24th t o J u l y 8 t h  J u l y 19th  J u l y 8th t o J u l y 19th  J u l y 27th  J u l y 19th t o J u l y  N u m e r i c a l Assessment:  10 = Few  f o r Thysanoptera  20 = Many  27th  30 = V e r y Many  Numerical  Assessment:  f o r Hymenoptera  Average c o u n t s a t two l o c a t i o n s i n three f i e l d s f o r f i v e c o l l e c t i o n dates.  F i g u r e 4.1.2.2  I n s e c t s caught on s t i c k y t r a p s i n t h e C r e s t o n v a l l e y i n t h r e e f i e l d s ; two s i t were l o c a t e d on each, f i e l d and two t r a p were e s t a b l i s h e d a t each. s i t e .  Sticky traps: Creston  44 4.1.2.3  Discussion  S t i c k y t r a p s were u s e f u l t o m o n i t o r f l y i n g i n s e c t . for  They have drawbacks,  i n s t a n c e , t h e " s t i c k u m " m a t e r i a l i s u n p l e a s a n t t o h a n d l e and i f t h e r e i s  r a i n o r d u s t i t has a tendency t o l o s e i t s e f f e c t i v e n e s s ; b i r d s p e r c h on the boards and p i c k o f f a l o t o f t h e l a r g e r i n s e c t s .  Whether t h e boards  f a c e d n o r t h o r south made l i t t l e d i f f e r e n c e t o t h e t y p e o r q u a n t i t y o f i n s e c t s c o l l e c t e d , and t h e t r a p s were n o t u s e f u l i n i n d i c a t i n g t h e d i r e c t i o n o f i n s e c t m i g r a t i o n on a l o c a l s c a l e .  More f r e q u e n t  c o l l e c t i o n s would i n a l l p r o b a b i l -  i t y y i e l d i n f o r m a t i o n t h a t would be more v a l u a b l e . 4.1.3  P i t F a l l Traps  4.1.3.1 The  M a t e r i a l s and Methods same f i e l d s and l o c a t i o n s were used f o r t h e p i t f a l l t r a p s as were  used f o r t h e s t i c k y t r a p s .  These t r a p s were made u s i n g 3 1/2 i n c h wide  Mason j a r s which were p l a c e d w i t h t h e t o p o f t h e j a r l e v e l w i t h t h e ground. A l c o h o l ( 7 0 % ) , used as t h e k i l l i n g and p r e s e r v i n g medium, was added t o each jar  i n the f i e l d .  Two t r a p s were p l a c e d a t each l o c a t i o n ; one a meter n o r t h  o f a p o s t , t h e o t h e r a meter s o u t h o f t h e same p o s t .  C o l l e c t i o n d a t e s were  June 8 t h ( r e p r e s e n t i n g May 30th t o June 8 t h ) , June 28th ( r e p r e s e n t i n g June 8th t o June 2 8 t h ) , J u l y 8 t h ( r e p r e s e n t i n g June 28th t o J u l y 8 t h ) , J u l y 1 5 t h ( r e p r e s e n t i n g J u l y 8 t h t o J u l y 1 5 t h ) , J u l y 27th ( r e p r e s e n t i n g J u l y 15th t o J u l y 27th).  Samples as c o l l e c t e d were p l a c e d i n methaldehyde.  Samples were grouped a c c o r d i n g  t o " a c t i v i t y " and were t a b u l a t e d as  average numbers p e r f i e l d p e r c o l l e c t i o n . 4.1.3.2 The  Observations  and R e s u l t s  r e s u l t s of the p i t f a l l  t r a p s a r e found i n F i g u r e 4.1.3,1, and t h e  organisms a r e grouped under t h e t h r e e headings o f " B e n e f i c i a l " , "Scavenger", and  " D e s t r u c t i v e " (Tables 4.1.3.1 and 4.1.3.2).  Such headings a r e s e l f -  45 T a b l e 4.1.3.1 Organisms c o l l e c t e d by p i t f a l l t r a p s a t C r e s t o n : Grouping o f o r d e r s , f a m i l i e s and/or genus by common name i n t o t h r e e groups a s s o c i a t e d w i t h t h e i r a c t i v i t i e s , a)  Beneficial Taxon  Common name  - ARANEIDA  - Spiders  -  - Rove b e e t l e s  -  b)  Staphylinidae Carabidae  - Ground b e e t l e s  Histeridae  - Hister  beetles  Scavengers Taxon  Common name  -  Silphidae  - Burying  -  Scarabaeidae  - Scarab b e e t l e s  -  Nitidulidae  -  c)  Predacious)  beetles  - Sap b e e t l e s - Spring t a i l s  Thysanura  Destructive Taxon  Common name  -  - Weevils  Curculionidae  -  Dermestidae  - Skin beetles  -  Tenebrionidae  - Darkling beetles  -  Elateridae  - C l i c k beetles  -  Chrysomelidae  - Leaf b e e t l e s  - Deroceras  sp.  - Slugs  46-  Table 4.1.3.2 ^ Q r g a n i s m s . Q O l l e c t e d . i n p i t f a l l t r a p s at Creston:  samples taken on  f o u r separate dates from two l o c a t i o n s i n each o f three f i e l d s . Dates o f C o l l e c t i o n s June 8  June 28  J u l y 15  J u l y 27  Field 1 Beneficial  Spiders  Ground b e e t l e s  Spiders  Spiders  Ground b e e t l e s  Rove b e e t l e s  Ground b e e t l e s  Ground b e e t l e s Rove b e e t l e s Hister beetles  Scavengers  Sap b e e t l e s  Sap b e e t l e s  Burying b e e t l e s  Burying b e e t l e s  Spring  Scarab b e e t l e s  Scarab b e e t l e s  tails  Burying b e e t l e s Destructive  Field 5  Weevils  Weevils  Weevils  Darkling beetles  Beneficial  Ground b e e t l e s  Ground b e e t l e s  Spiders  Sp i d e r s  Rove b e e t l e s  Rove b e e t l e s  Ground b e e t l e s  Ground b e e t l e s  Hister beetles  Rove b e e t l e s  Rove b e e t l e s Scavengers  Hister beetles  Burying b e e t l e s  Burying b e e t l e s  Burying b e e t l e s  Burying b e e t l e s  Spring  Scarab b e e t l e s  Spring  Scarab b e e t l e s  Sap b e e t l e s  tails  Spring  tails  tails  Sap b e e t l e s Destructive  Weevils  Slugs  Slugs  C l i c k beetles  C l i c k beetles  Skin beetles Leaf b e e t l e s Field 6 Beneficial  Spiders  Spiders  Ground b e e t l e s  Spiders  Ground b e e t l e s  Ground b e e t l e s  Rove b e e t l e s  Ground b e e t l e s  Rove b e e t l e s  Hister beetles  Rove b e e t l e s Hister beetles  Scavengers Destructive  Burying b e e t l e s  Sap b e e t l e s  Burying b e e t l e s  Scarab b e e t l e s  Scarab b e e t l e s  Sap b e e t l e s  Skin beetles  Skin beetles  Skin beetles. Spring Slugs  tails  Scarab b e e t l e s Weevils  Figure  4.1.3  Graph showing i n s e c t s c o l l e c t e d i n p i t - f a l l t r a p s i n the C r e s t o n v a l l e y i n t h r e e f i e l d s . Traps were l o c a t e d a t t w c s i t e s on each f i e l d and two t r a p s were l o c a t e d a t each s i t e . Assessment i s t h e average number o f i n s e c t s c o l l e c t e d i n each t a x o n f o r each d a t e .  /on 60-  4 7 (r.  C r e s t o n : Pit Fail T r a p s  Beneficial I Scavenger " Destructive 3  Field 1  504030-  20 10  70-1 •£  60-  B S D  B S D  B S  B S D  Field 5  iS 5 0 H  1o l/l  40.  u  *<5 3 0  I  I  E  Z  20  70 60  1  B S D  Field  B S D  11  B S D  B S D  6  50 40 302010-  1  June 8  June 28 J u l y 15 Sample Date  July 27  48 e x p l a n a t o r y and a r e used by B o r r o r and Delong  (1963).  A " b i o l o g i c a l c o n t r o l " appears t o be i n e f f e c t i n a l l t h r e e f i e l d s and on a l l t h e d a t e s .  The s p r a y c o n t r o l on June 22nd d i d n o t a f f e c t t h e "Ben-  e f i c i a l " o r " S c a v e n g e r " organisms t o any g r e a t 4.1.3.3  extent.  Discussion  I t was hoped t h a t t h e p i t f a l l slug populations.  t r a p s would y i e l d more i n f o r m a t i o n on  A v i s u a l i n s p e c t i o n o f the f o l i a g e o f t h e crop d i d  i n d i c a t e f e e d i n g by a r a t h e r l a r g e p o p u l a t i o n o f s l u g s .  Samples o f s l u g s  c o l l e c t e d were c l a s s i f i e d as t h e common s l u g D e r o c e r a s r e t i c u l a t u m ( M u l l e r ) . Pit  fall  trol  t r a p s p r o v e d t o f u r n i s h u s e f u l i n f o r m a t i o n on t h e b i o l o g i c a l  i n e f f e c t ; more f r e q u e n t  c o l l e c t i o n s would have been u s e f u l .  con-  The  m o n i t o r i n g o f s l u g s and s n a i l s would be b e t t e r u n d e r t a k e n u s i n g b a i t s as d e s c r i b e d by C r a w f o r d - S i d e b o t h a m (1972). those o f t h e c l o v e r root c u r c u l i o . 4.1.4  Weevils  c o l l e c t e d on J u l y 27th were  S o i l I n s e c t Sampling  4.1.4.1  M a t e r i a l s and Methods  A s o i l c o r e o f d i m e n s i o n s 10 c e n t i m e t e r s g i v i n g a volume o f 785 c u b i c c e n t i m e t e r s  deep by 10 c e n t i m e t e r s  was u s e d .  diameter,  T h i s i s a commonly u s e d  d e v i c e o f t h e " p l u g g e r " t y p e t o g i v e an e s s e n t i a l l y u n d i s t u r b e d  cylinder of  soil. A)  For root examination  4 d a t e s were sampled w i t h t h e p l u g g e r  (May 3 0 t h ,  June 1 6 t h , J u l y 1 4 t h and August 8 t h ) , and one d a t e (September 25) an a r b i t r a r y q u a n t i t y was sampled from t h e p l o u g h e d f i e l d s .  A sample c o n s i s t e d o f two  p l u g s , and t h e s e p l u g s were washed c a r e f u l l y t o a v o i d breakage and l o s s o f roots.  Damage assessment on t h e 3 0 t h o f May was as t o t h e p r e s e n c e o r  absence o f r o o t s c o r i n g .  On t h e 1 6 t h June a n u m e r i c a l  assessment was  a l l o c a t e d r a n g i n g from Q t o 5 f o r a l l f o u r l o c a t i o n s on each o f s i x f i e l d s . On t h e 14th J u l y and 4 t h August o n l y two samples were t a k e n from each  field.  49 B)  For i n s e c t e x a m i n a t i o n , s a m p l i n g dates took p l a c e on the 5th August,  18th August and 25th September.  The August samples were f r o z e n , w h i l e the  September samples were s t o r e d a t 8°c.  The method o f e x t r a c t i o n s  consisted  of the use o f s i e v e s and d r y e x t r a c t i o n s , w i t h l i g h t and heat on t h e August samples and wet e x t r a c t i o n s on the September samples. e x t r a c t i o n s p l a s t i c f u n n e l s and c h e e s e c l o t h were used.  I n t h e d r y and  wet  In dry e x t r a c t i o n s  i n s e c t s were a c t i v a t e d so t h a t they m i g r a t e away from the l i g h t and heat then c o l l e c t e d a t t h e base o f t h e f u n n e l . 4 days.  and  Time f o r e x t r a c t i o n i s a p p r o x i m a t e l y  The wet e x t r a c t i o n procedure i s much the same as t h e d r y except t h a t  water i s p l a c e d on the sample and a l i q u o t s are t a k e n every h a l f hour as the l i g h t and heat are i n c r e a s e d . C)  Nematode e x a m i n a t i o n s were undertaken a t the A g r i c u l t u r e Canada  Research S t a t i o n , Vancouver. from each f i e l d August. D)  Samples t o be examined c o n s i s t e d o f 4 cores  ( w i t h p l a n t s i n s i t u ) p l a c e d i n j i f f y p o t s on the 5 t h  The e x t r a c t i o n o f nematodes from t h e r o o t s was by way o f m i s t i n g . For assessment  o f pathogens  ( f u n g i and b a c t e r i a ) , p l a n t s were t a k e n  from f i e l d s 2, 3, 4, and 5 on the 25th September and s t o r e d i n p l a s t i c bags at 8°C.  These samples were s u b s e q u e n t l y examined by Dr. R. Copeman, Depart-  ment o f P l a n t S c i e n c e , the U n i v e r s i t y o f 4.1.4.2 A)  B.C.  O b s e r v a t i o n s and R e s u l t s Root damage r a t i n g s :  The r e s u l t s are p r e s e n t e d i n T a b l e 4.1.4.1.  I t i s noteworthy t h a t damage appears i n almost a l l samples and t h a t the r o o t s d e t e r i o r a t e as t h e summer p r o g r e s s e s . the end o f May.  Moreover,  damage b e g i n s b e f o r e  Larvae f i t t i n g the d e s c r i p t i o n g i v e n by Davidson and P e a i r s  (1960) o f the c l o v e r r o o t c u r c u l i o were observed i n t h e r o o t zone o f each core on dates May B)  30th and June 16th.  S o i l i n s e c t e x a m i n a t i o n s u s i n g s i e v e s and d r y e x t r a c t i o n s proved  to be o f l i t t l e v a l u e ; i t appeared t h a t most organisms p e r i s h e d i n s t o r a g e .  50 T a b l e 4.1.4.1 An e s t i m a t i o n o f r o o t damage by date t o w h i t e c l o v e r p l a n t s i n farmers'  f i e l d s i n Creston  Location  Field  30/5  (Wyndell South)  (Eastman)  (Huscroft East)  1 2 3 4  (Wyndell North)  + +  3 2 3 2  (5) (7) (-) (3)  1 2 3 4  3 (!) 2 (3) 1 CH) 2 (5)  1 2 3 4  3 3 4 3  (-) (") (") (1)  3 3 0 0  (-) (-) (-) (-)  1 2 3 4  1 2 4 3  (-) (2) (1) (7)  1 2 3 4  1 1 2 3  (2) (3) (4) (2)  + +  (Huscroft West)  (Ogilvie)  Date c o l l e c t e d 14/7 16/6 3  4  4  4  2 3  Damage Rating. v i s i b l e insect injury no v i s i b l e i n s e c t i n j u r y  4/8  a)  For date - 30/5/77  +  b)  For dates 16/6, 14/7, and 4/8 r a n k i n g "damage" from 1 t o 5 w i t h 1 as v e r y s l i g h t i n j u r y t o 5 f o r e x t e n s i v e i n j u r y r e s u l t i n g i n crown r o t .  c)  Numbers i n b r a c k e t s a r e numbers o f l a r v a e c o l l e c t e d i n s o i l and r o o t c o r e s .  i  51 C) Nematode e x a m i n a t i o n s : The  occurrence of Pratylenchus  be n o t e d t h a t f i e l d 2 was (personal D) orders  The  r e s u l t s a r e p r e s e n t e d i n T a b l e 4.1.4.2.  spp. i n f i e l d 2, may  a t one  t i m e i n hops.  be o f c o n c e r n ; i t i s t o  Other f i e l d s a r e  "normal"  communication - Dr. M c E l r o y , A g r i c u l t u r e Canada, V a n c o u v e r , B.C.). P r e l i m i n a r y p l a n t pathogen e x a m i n a t i o n s : O b s e r v a t i o n s i n May  o f p a t h o l o g i c a l n a t u r e i n f i e l d s 3 and  normal.  4.  On September 2 5 t h , a f t e r a l l f i e l d s had  Other f i e l d s  p l a n t s examined i n the f i e l d were d y i n g . from f i e l d s 2, 3, 4 and  5 has  appeared  been p l o u g h e d ,  p l a n t s were found i n f i e l d 2, w h i l e i n f i e l d s 3 and  The  healthy  4 a f t e r ploughing, a l l  P r e l i m i n a r y pathogen i d e n t i f i c a t i o n  i n d i c a t e d the presence of s e v e r a l  s p e c i e s o f f u n g i i n damaged r o o t s .  revealed  Fusarium species  that  Fusarium occurred  p r e d o m i n a n t l y i n f i e l d 2 were not so predominant i n f i e l d s 3, 4 and 4.1.4.3  Discussion  It i s evident  from T a b l e 4.1.4.1 t h a t most o f the r o o t damage by  clover root c u r c u l i o i s very have a b e a r i n g The  5.  l i k e l y general  on t h e v i g o u r , l o n g e v i t y and  the  t h r o u g h o u t t h e v a l l e y and  could  seed y i e l d o f w h i t e c l o v e r  stands.  r o o t damage o b s e r v e d on a l l r o o t s f i t t e d c l o s e l y the d e s c r i p t i o n g i v e n  by K i l p a t r i c k and  Dunn (1961).  However, more samples and more s a m p l i n g d a t e s  would be r e q u i r e d t o r e v e a l t h e e x t e n t o f damage t h r o u g h o u t the a r e a . i s evident  It  from t h e absence o f l a r v a e i n t h e J u l y and August samples t h a t  most o f t h e i n i t i a l damage o c c u r s i n May t h a t r o o t washing was  and  e a r l y June.  not e s s e n t i a l , but the g e n e r a l  r o o t s i n the f i e l d would p r o v i d e  I t was  observed  examination of  clover  a good i n d i c a t i o n o f the s u c c e s s i o n  of  infestation. The  p r e s e n c e o f F u s a r i u m spp.  i s i n agreement w i t h K i l p a t r i c k and (1969).  o f f u n g i i n the damaged w h i t e c l o v e r Dunn (1961) and  roots  a l s o the work by O'Rourke  These two p a p e r s i n d i c a t e t h a t Fusarium spp.  a r e normal s o i l  residents  dis-  52  T a b l e 4.1.4.2 Nematode c o u n t s * o b t a i n e d by e x t r a c t i o n from s o i l - c l o v e r Creston.  F i e l d s a m p l i n g 5/8/77.  Counts as number o f nematodes  p e r gram o f a i r d r y r o o t s . Sampling 2 1 Pratylenchus ( s t y l e bearing) Lesion  c o r e s from  area 3  4  Field 1  0  0  0  0  Field 2  374  331  44  0  Field 3  0  0  0  0  Field 4  0  0  120  0  Field 5  0  0  0  0  Field 6  0  6  0  0  Field 1  0  0  0  7  Field 2  20  0  0  30  Field 3  0  0  0  0  Field 4  0  0  0  20  Field 5  0  0  0  0  Field 6  0  0  5  0  Field 1  24  21  50  26  Field 2  7  15  0  0  Field 3  0  160  103  20  Field 4  0  86  14  0  Field 5  23  0  0  0  Field 6  0  6  32  0  Ditylenchus ( s t y l e bearing) Stem  Aphelenchus Leaf  ( s t y l e bearing)  *Made by t h e s t a f f o f the Research S t a t i o n , A g r i c u l t u r e Canada, Vancouver, B.C.  53 b u t t h e y e n t e r t h e p l a n t when i t i s under s t r e s s .  I feel that the feeding  o f t h e c l o v e r r o o t c u r c u l i o on t h e C r e s t o n w h i t e c l o v e r i s a m a j o r c o n t r i b u t o r t o t h e e n t r y o f t h e pathogens i s o l a t e d by Dr. Copeman. 4.2  S o i l Sampling f o r F e r t i l i t y  4.2.1  M a t e r i a l s and Methods In s o i l s a m p l i n g  a one-half  i n c h s o i l c o r e r was employed.  Cores were  taken t o plough depth.  Subsampling a t each f i e l d  l o c a t i o n was done on a  "square g r i d " p a t t e r n .  The d a t e s f o r c o l l e c t i o n were May 3 0 t h and August  28th; 48 samples i n a l l were c o l l e c t e d . M a j o r a v a i l a b l e n u t r i e n t s i n t h e s o i l s o f t h e s t u d y a r e a s were d e t e r mined u s i n g t h e Morgan's U n i v e r s a l System.  S o i l r e a c t i o n was d e t e r m i n e d  u s i n g customary p r o c e d u r e s by employing a pH m e t e r . 4.2.2  Observations  and R e s u l t s  A v a i l a b i l i t y o f major n u t r i e n t s was s i m i l a r i n a l l f i e l d s and s i t e s within fields.  N i t r a t e n i t r o g e n averages were low a t 8 kgs/ha f o r t h e  30th May s a m p l i n g  and a t 7 kgs/ha f o r t h e 5 t h August s a m p l i n g .  Phos-  phorous r e a d i n g s were medium t o h i g h a t 25 t o 50 p a r t s p e r m i l l i o n . nesium l e v e l s were v e r y low a t 12 p a r t s p e r m i l l i o n , w h i l e c a l c i u m were v e r y h i g h a t 250 p a r t s p e r m i l l i o n .  Maglevels  S o i l r e a c t i o n a t a l l l o c a t i o n s was  m i l d l y a l k a l i n e a t pH 7.1 t o 7.8. 4.2.3  Discussion The  q u i c k t e s t system i s adequate f o r t r o u b l e s h o o t i n g , b u t as a  f e r t i l i z e r recommendation i t i s n o t p r e c i s e .  The s o i l r e a c t i o n and n u t r i e n t  l e v e l s approximate those given f o r t h e area i n t h e s o i l W i t t n e b e n and S p r o u t (1971) .  s u r v e y r e p o r t by  The m i l d l y a l k a l i n e r e a c t i o n o f t h e s o i l  c o u p l e d w i t h t h e h i g h l e v e l o f c a l c i u m c o u l d have a b e a r i n g on t h e l e v e l o f a v a i l a b l e phosphorous i n t h e s o i l .  54 4.3  Phytomass Sampling  4.3.1  For Dry M a t t e r Y i e l d s on 30-5-77  4.3.1.1  M a t e r i a l s and Methods  Sampling was  c a r r i e d out on the 30th May.  was used and p l a c e d randomly of  A o n e - q u a r t e r meter quadrat  t w i c e a t each l o c a t i o n i n each f i e l d .  top growth were t a k e n as c l o s e t o t h e ground as p o s s i b l e .  was  then d r i e d i n the p o t - h o l e d r i e r a t U.B.C. and  4.3.1.2  The  Clips material  weighed.  O b s e r v a t i o n s and R e s u l t s  The r e s u l t s are t a b u l a t e d i n T a b l e 4.3.1.1 and graphed  i n F i g u r e 4.3.1.1.  I t i s t o be seen t h a t t h e r e i s a f a i r l y wide d i f f e r e n c e i n y i e l d s between f i e l d s even a t a date as e a r l y as 4.3.1.3  May.  Discussion  More and l a r g e r samples would have g i v e n g r e a t e r p r e c i s i o n ; the sheer volume o f samples t o s t o r e and t r a n s p o r t and the l a b o u r i n making p l a n t s e p a r a t i o n s would r e n d e r t h e e f f o r t s o f q u e s t i o n a b l e w o r t h . 4.3.2  For Dry M a t t e r Y i e l d s on 5-8-77  4.3.2.1  M a t e r i a l s and Methods  Sampling was  c a r r i e d out on August 5 t h .  The sampling p r o c e d u r e was  the  same as a f o r e m e n t i o n e d i n S e c t i o n 4.3.1, except t h a t t h r e e samples p e r l o c a t i o n i n each f i e l d were t a k e n . to  swathing the c r o p .  H a r v e s t i n g was  timed t o o c c u r j u s t p r i o r  The samples were a i r - d r i e d a t C r e s t o n .  was t r a n s p o r t e d t o Vancouver  and p r o c e s s e d .  The  material  S e p a r a t i o n o f g r a i n s t u b b l e from  the p r e v i o u s y e a r ' s crop was done p r i o r t o the t a k i n g o f t o t a l w e i g h t .  The  samples were weighed a f t e r s t a n d i n g a t room temperature f o r a number o f weeks. 4.3.2.2  O b s e r v a t i o n s and R e s u l t s  P l a n t top growth y i e l d s are g i v e n i n : T a b l e 4.3.2.1 and i n F i g u r e 4.3.2.1. A g a i n a s u b s t a n t i a l v a r i a t i o n i n y i e l d s between f i e l d s i s r e c o r d e d .  T a b l e 4.3:1.1 Top weight sampling i n s i x f i e l d s i n C r e s t o n i n May 1977. 2 . ( w e i g h t s i n gms. p e r 1/4 m q u a d r a t ) •• • kgs/ha Mean SD CV% Range  No. Samples  F i e l d 1 Wyndell South  3640  91  16  18  62 - 113  8  F i e l d 2 Eastman  2200  55  13  24  35 -  74  8  F i e l d 3 Huscroft East  2200  55  9  16  37 -  63  8  F i e l d 4 H u s c r o f t West  2400  60  6  10  49 -  66  8  Field 5 Ogilvie  3400  85  17  20  58 - 116  8  F i e l d 6 Wyndell N o r t h  3520  88  14  16  73 - 111  8  T a b l e ,4.3.2.1. Top weight sampling i n s i x f i e l d s i n C r e s t o n i n August. "..".(weights i n gms. per 1/4  m  quadrat) Range  No. Samples  31  106 - 261  12  16  18  65 - 122  12  132  19  14  95 - 156  12  5280  132  51  39  68 - 263  12  Field 5 Ogilvie  6560  164  46  28  87 - 221  12  F i e l d 6 Wyndell N o r t h  7320  183  50  27  109 - 248  12  kgs/ha  Mean  SD  CV%  F i e l d 1 Wyndell"South  6040  151  47  F i e l d 2 Eastman  3640  91  F i e l d 3 H u s c r o f t East  5280  F i e l d 4 H u s c r o f t West  T a b l e 4.3.3.1 Seed weight i n s i x f i e l d s i n C r e s t o n , August 1977. 5 (wei g h t s i n gms. p e r 1/4 kgs/ha  m quadrat) 2  Mean  SD  CV%  Range  No . Samples  F i e l d 1 Wyndell South  672  16.8  5.3  31  11.2 - 30.8  12  F i e l d 2 Eastman  468  11.7  1.6  13  9.6 - 15.1  12  F i e l d 3 Huscroft East  972  24.3  4.5  18  16.9 - 29.4  12  F i e l d 4 H u s c r o f t West  756  18.9  8.8  47  6.9 - 28.3  12  Field 5 Ogilvie  468  11.7  5.6  48  5.3 - 21.1  12  F i e l d 6 Wyndell N o r t h  480  12.0  4.0  33  6.7 - 16.8  12  F i g u r e 4.3.1.1  The v a r i a t i o n i n w e i g h t o f t o p growth, i n s i x f i e l d s i n C r e s t o n , 30th May 1977 (l): Two q u a d r a t s from k r e p l i c a t e s i n each f i e l d , showing: a) b) c)  The a r i t h m e t i c mean f o r each f i e l d • The s i m p l e range by v e r t i c a l b a r ± one s t a n d a r d d e v i a t i o n from t h e mean by h o r i z o n t a l b a r s  Creston: weight of top growth (1)  120  100  80  60  40  20  1  3  Field  F i g u r e U.3.2.1  The v a r i a t i o n i n w e i g h t o f t o p growth i n s i x f i e l d s i n C r e s t o n , August 1977 (2) Three q u a d r a t s from h r e p l i c a t e s i n each f i e l d showing a) b) c)  The a r i t h m e t i c mean f o r each f i e l d The s i m p l e range by v e r t i c a l b a r +_ one s t a n d a r d d e v i a t i o n from t h e mean by h o r i z o n t a l b a r s  •  Creston: weight of top growth (2) 260  240  220  200  180  H  160 k  140  120  100r  80  60  i_ 1  6  Field  58 4.3.2.3  Discussion  Harvesting minimum.  The  o f the m a t e r i a l was  s m a l l quadrat was  c a r e f u l l y u n d e r t a k e n t o keep l o s s t o a  useful i n t h i s respect.  can p a r t i a l l y e x p l a i n the l a r g e s t a n d a r d observed i n one  Soil variability  d e v i a t i o n s ; i t was  further .  s e t . w i t h i n a s i n g l e f i e l d t h a t c l o v e r i n c e r t a i n areas o f  d i f f e r e n t s o i l t e x t u r e would f l o w e r p r e m a t u r e l y and not be v e r y t a l l , whereas i n o t h e r areas c l o v e r remained v e g e t a t i v e and grew v i g o r o u s l y .  Disease,  p e s t s and o t h e r f a c t o r s u n d o u b t e d l y c o n t r i b u t e d t o y i e l d v a r i a b i l i t y . 4.3.3  Seed and  4.3.3.1  I n f l o r e s c e n c e Y i e l d s on 5-8-77  M a t e r i a l s and Methods  I n f l o r e s c e n c e s were s e p a r a t e d from t h e r e s t o f the m a t e r i a l as per s e c t i o n 4.3.2. thresher.  The  4.3.3.2  They were t h e n counted and passed t h r o u g h the head  seed was  hand winnowed, and  t h e n c l e a n e d by p a s s i n g  through a s e r i e s of s i e v e s ,  f i n a l l y weighed.  O b s e r v a t i o n s and  Seed h a r v e s t  Results  and number o f i n f l o r e s c e n c e s per u n i t a r e a a r e  i n T a b l e 4.3.3.1 and 4.3.3.2 and F i g u r e s 4.3.3.1 and 4.3.3.2. and 6 gave the l o w e s t y i e l d s and b o t h seed and  inflorescences.  i n f l o r e s c e n c e s per h e c t a r e was y i e l d s were e s t i m a t e d  illustrated  F i e l d s 2, 5  f i e l d s 3 and 4 gave the h i g h e s t y i e l d s , f o r  The  general  t r e n d from f i e l d t o f i e l d f o r seed  y i e l d t o approximate i n f l o r e s c e n c e number i s e v i d e n t .  4.3.3.3  harvested  estimated  t o range from 468  t o be 11.5 t o 972  The  average number o f  m i l l i o n ; the average seed  kgs per h e c t a r e  (418-868 l b s / a c  Discussion  I t was  a n t i c i p a t e d t h a t the s m a l l number and  r e s u l t i n a r a t h e r large standard  deviation.  s i z e o f the samples would  However i t can be seen t h a t  i n c r e a s i n g seed y i e l d tends t o r e l a t e t o a moderate y i e l d o f s t a n d i n g a heavy top growth tends t o suppress number o f heads and  crop;  seed y i e l d on a  59 T a b l e 4.3.5.2 Number o f heads p e r u n i t a r e a i n s i x f i e l d s i n C r e s t o n t a k e n i n August 1977 No. q u a d r a t s / Sample  Mean  SD  cv%  323  61  19  232 -- 413  12  F i e l d 2 Eastman  213  55  26  92 -- 314  12  F i e l d 3 Huscroft East  363  55  15  278 -- 435  12  F i e l d 4 H u s c r o f t West  326  78  24  227 -- 465  12  Field 5 Ogilvie  257  49  19  173 -- 319  12  F i e l d 6 Wyndell N o r t h  239  80  33  129 -- 375  12  F i e l d 1 Wyndell  South  Range  T a b l e 4.3.3.3 Dependence o f seed y i e l d on number o f i n f l o r e s c e n c e s per u n i t area.  L i n e a r r e g r e s s i o n e q u a t i o n s and  c o r r e l a t i o n c o e f f i c i e n t s f o r s i x f i e l d s i n Creston, August, 1977. Field 1  Y = 0.98 + 0.05X  r = 0..56  Field 2  Y = 7.21 + 0.02X  r = 0,,73 **  Field 3  Y = 8.89 + 0.04X  r = 0.,52  Field 4  Y = -10.15 + 0.09X  r = 0. yg**  Field 5  Y = -12.20 + 0.09X  r = 0.,81**  Field 6  Y = 4.42 +•0.03X  r = 0..75**  r  .01(10) = 0.7079**  Number o f i n f l o r e s c e n c e s - X; seed y i e l d - Y Number o f samples p e r t r e a t m e n t 12  Figure  .4.3,3.1  The v a r i a t i o n i n w e i g h t o f seed from s i x f i e l d s i n C r e s t o n , August 1977: Three q u a d r a t s from 4 r e p l i c a t e s i n each f i e l d showing a) b) c)  The a r i t h m e t i c mean f o r each f i e l d The s i m p l e range by v e r t i c a l b a r f_ one s t a n d a r d d e v i a t i o n from t h e mean by h o r i z o n t a l b a r s  Loir Creston: seed weight  301-  25  20  15  10  0^  L.  1  3 Field  6  Figure  4.3.3.2  The v a r i a t i o n i n t h e number o f heads per u n i t area i n s i x f i e l d s i n Creston, August 1977: Three quadrats from 4 r e p l i c a t e s i n each f i e l d showing a) b) c)  The a r i t h m e t i c mean f o r each f i e l d The s i m p l e range by v e r t i c a l b a r +_one s t a n d a r d d e v i a t i o n from t h e mean by h o r i z o n t a l b a r s  CRESTON: Heads Per Unit Area  illr.  4501  400  350  -3  300 \  |  250 [  o a>  Z  200  150  100  6 Field  62 u n i t area.  T a b l e 4.3.3.3 l i s t s t h e l i n e a r r e g r e s s i o n e q u a t i o n s and c o r -  r e l a t i o n c o e f f i c i e n t s f o r i n f l o r e s c e n c e numbers and seed y i e l d on a u n i t area.  I f seed y i e l d i s r e g a r d e d as the dependent v a r i a b l e t h e r e i s a s t r o n g  s u g g e s t i o n t h a t as numbers o f i n f l o r e s c e n c e s i n c r e a s e t h e n seed y i e l d increases. ship.  Hawkins (1956) w o r k i n g w i t h r e d c l o v e r f i n d s a s i m i l a r  I f my seed y i e l d s a r e compared t o f a r m e r s ' y i e l d s ,  also  relation-  t h e farmers a r e  e x p e r i e n c i n g a seed l o s s w h i l e h a r v e s t i n g up t o 50%. 4.3.4  I n d i v i d u a l Head E x a m i n a t i o n s  4.3.4.1  M a t e r i a l s and Methods  P r i o r t o h a r v e s t twenty-one i n f l o r e s c e n c e s were t a k e n from each s a m p l i n g a r e a i n each f i e l d . the  F i v e heads were s e l e c t e d a t random, rubbed t o remove  seeds, and then winnowed.  The seeds were then counted and examined f o r  i n s e c t damage and o t h e r u n d e s i r a b l e f a c t o r s . 4.3.4.2  O b s e r v a t i o n s and R e s u l t s  I t i s n o t a b l e t h a t b o t h the average number o f seeds p e r head and s t a n d a r d d e v i a t i o n s a r e s i m i l a r f o r a l l f i e l d s except f i e l d 5; means l i e between 144 to  161 seeds p e r head; i n s e c t damaged seeds ranged from 3% t o 10% ( T a b l e  4.3.4.1 and F i g u r e 4.3.4.3  4.3.4.1).  Discussion  The f a c t o r t h a t caused the l o w e r i n g i n seeds per head i n f i e l d 5 d i d not a f f e c t t h e number o f heads p e r u n i t a r e a and remains u n e x p l a i n e d ; perhaps i t c o u l d be a t t r i b u t e d t o a b e r r a n t p o l l i n a t i o n o r t o e r r a t i c i n s e c t damage. T a b l e 4.3.4.2 shows the "independence" o f i n s e c t damaged seed t o the i n f l u e n c e of  location.  4.3.5  L e a f A r e a , P e t i o l e Length and Peduncle Length  4.3.5.1 A)  M a t e r i a l s and .Methods Leaf Area:  Four l e a v e s and t h e i r p e t i o l e s were c o l l e c t e d a t random  63 T a b l e 4.3.4.1 Number o f seeds p e r head i n s i x f i e l d s i n C r e s t o n , August 1977. No. heads/ Sample  Mean  SD  CV%  F i e l d 1 Wyndell South  151  73  48  13 - 259  20  F i e l d 2 Eastman  161  94  58  31 - 376  20  F i e l d 3 Huscroft East  160  71  44  58 - 325  20  F i e l d 4 H u s c r o f t West  144  94  65  36 - 347  20  97  59  61  37 - 243  20  161  82  51  31 - 311  20  Field 5 Ogilvie F i e l d 6 Wyndell N o r t h  Range  T a b l e 4.3.4.2 Contingency t a b l e f o r i n s e c t -•damaged seed :from i n d i v i d u a l seed~'.heads from C r e s t o n f i e l d i n August 1977.  C l a s s e s a r e 'percentag e o f seeds damaged" Class  Field  Name South  0-5%  5-:100%  Total  4 (6.10)  6 .90) (3  10  9 (9.14)  6 .86) (5  15  1  Wyndell  2  Eastman  3  Huscroft East  13 (12.19)  7 (7 .81)  20  4  H u s c r o f t West  11 (12.19)  9 (7 .81)  20  5  Ogilvie  11 (12.19)  9 (7 .81)  20  6  Wyndell  16 (12.19)  4 (7 .81)  20  North  64  Total:  41  Expected v a l u e s i n b r a c k e t s 2 Actual  x  =5.72  Expected x^ (0.05)(5) =: 11.07  105  Figure  4,3,4.1  The v a r i a t i o n i n number o f seeds p e r head i n s i x f i e l d s i n C r e s t o n , August 1977: F i v e i n f l o r e s c e n c e s t a k e n from twenty-one i n f l o r e s c e n c e s c o l l e c t e d i n t h e f i e l d from f o u r r e p l i c a t e s from each f i e l d showing a) b) c)  The a r i t h m e t i c mean f o r each f i e l d • The s i m p l e range by v e r t i c a l b a r s + one s t a n d a r d d e v i a t i o n from t h e mean by h o r i z o n t a l b a r s  400  CRESTON: Seeds per head  350  300  250 a  a> a> a  "S 200 a>  e z 150  100  50  3 Field  6  65 from each l o c a t i o n i n each f i e l d a t t h e b e g i n n i n g o f J u l y .  The l e a f a r e a  was e s t i m a t e d i n square c e n t i m e t e r s u s i n g t h e method o f W i l l i a m s e t a l . (1964). B)  P e t i o l e Length:  Was measured on t h e same samples as i n 4.3.5 A.  Length was measured from t h e base o f t h e t r i f o l i a t e  l e a f t o t h e base o f t h e  p e t i o l e where i t j o i n s t h e p l a n t stem o r s t o l o n . C)  Peduncle Length:  the same l o c a t i o n . to  Samples were c o l l e c t e d a t t h e same time and from  Length was measured from t h e base o f t h e i n f l o r e s c e n c e  t h e . p o i n t o f attachment o f t h e p e d u n c l e .to t h e stem o r s t o l o n .  4.3.5.2  O b s e r v a t i o n s and R e s u l t s  A)  Leaf Area:  A summary o f r e s u l t s o f t h e l e a f a r e a measurements i s  found i n T a b l e 4.3.5.1 and F i g u r e 4.3.5.1.  L e a f a r e a appears t o be s i m i l a r  i n a l l f i e l d s except 5 and 6, where t h e upper l i m i t o f t h e range was n o t i c e ably higher.  By comparing  t h e d a t a w i t h t h o s e g i v e n i n F i g u r e 4.3.2.1 i t i s  e v i d e n t t h a t a g e n e r a l i n c r e a s e i n l e a f a r e a f o l l o w s an i n c r e a s e i n t o p growth weight under f i e l d c o n d i t i o n s i n C r e s t o n .  Mean l e a f a r e a under  field  c o n d i t i o n s i n t h e C r e s t o n V a l l e y i s c o n s i s t e n t l y s m a l l e r than s i n g l e p l a n t i n g s at U.B.C. B)  P e t i o l e Length:  The r e s u l t s o f t h e measurements f o r l e n g t h o f l e a f  p e t i o l e a r e found i n T a b l e 4.3.5.2 and F i g u r e 4.3.5.2.  The means a r e s i m i l a r  from f i e l d t o f i e l d . C)  I n f l o r e s c e n c e Peduncle:  The r e s u l t s o f t h e measurements f o r t h e  l e n g t h o f i n f l o r e s c e n c e peduncle a r e found i n T a b l e 4.3.5.3 and i n F i g u r e 4.3.5.3. 4.3.5.3  Means a r e s i m i l a r from f i e l d t o f i e l d . Discussion  The method o f l e a f a r e a e s t i m a t i o n by comparing o u r l e a v e s w i t h those of  l e a v e s from samples o f known a r e a proved t o be r a p i d and r e l a t i v e l y  reliable.  66  Table 4.3.5.1 Average leaf areas i n centimeters for six fields in Creston i n July 1977. Mean No.  (cm)  No. leaves SD  CV%  Range  per sample  Field 1 Wyndell South  9  4  44  4  - 15.8  16  Field 2 Eastman  8  2  25  6.3-15.8  16  Field 3 Huscroft East  9  3  33  5  - 12.6  16  Field 4 Huscroft West  9  3  33  6.3-15.8  16  Field 5 Ogilvie  12  4  33  6.3 - 20  16  Field 6 Wyndell North  13  5  38  6.3 - 20  16  Table 4.3.5.2 Average leaf petiole lengths i n centimeters for six fields in Creston i n July 1977. No. petioles Mean SD CV% Range per sample Field 1 Wyndell South  19  5  26  9-25  16  Field 2 Eastman  22  3  14  16  - 27  16  Field 3 Huscroft East  18  4  22  11. - 23  16  Field 4 Huscroft West  20  5  25  14  - 29  16  Field 5 Ogilvie  19  5  26  11  - 27  16  Field 6 Wyndell North  21  3  14  14  - 26  16  Table 4.3.5.3 Average (inflorescence) peduncle lengths in centimeters for six fields i n Creston, July 1977. Mean  SD  CV%  Range  No. peduncles per sample  Field 1 Wyndell South  32  4  13  26  - 39  16  Field 2 Eastman  37  4  11  32  - 44  16  Field 3 Huscroft East  34  4  12  27 - 44  16  Field 4 Huscroft West  36  5  14  29  - 45  16  Field 5 Ogilvie  38  5  13  29  - 48  16  Field 6 Wyndell North  37  5  14  29  - 47  16  Figure  4.3.5.1.  The v a r i a t i o n i n l e a f a r e a i n s i x f i e l d s i n C r e s t o n , J u l y : 1977: Four l e a v e s r a n domly t a k e n from f o u r r e p l i c a t e s from each f i e l d , showing: a) b) c)  The a r i t h m e t i c mean f o r each f i e l d The s i m p l e range by v e r t i c a l b a r ± one s t a n d a r d d e v i a t i o n from t h e mean by h o r i z o n t a l b a r s  •  CRESTON: Leaf Area  30  r  25  20 h  15h  10h  5h  0  1  L  3  Field  6  F i g u r e 4.3.5-2  The v a r i a t i o n i n l e a f p e t i o l e length. • f o r s i x f i e l d s i n C r e s t o n , J u l y 1977: Four p e t i o l e s randomly t a k e n from r e p l i c a t e s from each, f i e l d showing: a) b) c)  The a r i t h m e t i c mean f o r each f i e l d The s i m p l e range by v e r t i c a l b a r ± one s t a n d a r d d e v i a t i o n from t h e mean by h o r i z o n t a l b a r s  •  <r  6S  CRESTON: Leaf Petiole  30 r  25  20  15  10  0<-  L 3  Field  5  6  Figure  4.3.5.3  The v a r i a t i o n i n i n f l o r e s c e n c e peduncle length f o r s i x f i e l d s i n the Creston v a l l e y , J u l y 1977: Four p e d u n c l e s r a n domly drawn from f o u r r e p l i c a t e s from each f i e l d , showing: a) b) c)  The a r i t h m e t i c mean f o r each f i e l d The s i m p l e range by v e r t i c a l b a r one s t a n d a r d d e v i a t i o n from t h e mean by h o r i z o n t a l b a r s  •  CRESTON: Infloresence peduncle  45r-  40h  35  30 h  25  20  15  10  1  3  Field  6  70 The comparison o f p e t i o l e and peduncle l e n g t h s may  a f f o r d some measure  of a s s e s s i n g a kind of hindrance to the a c t i v i t y of p o l l i n a t o r s .  By compar-  i n g F i g u r e s 4.3.5.2 and 4.3.5.3, peduncle l e n g t h i s on an average 15.8 longer than p e t i o l e length.  E x a m i n a t i o n o f T a b l e 4.3.5.4 shows  cms  little  r e l a t i o n s h i p between l e a f a r e a and p e t i o l e l e n g t h , o r between p e t i o l e l e n g t h and peduncle 4.3.6  length.  Swath Sampling f o r S t a n d i n g Crop and Seed Weight  4.3.6.1  M a t e r i a l s and Methods  L i n e t r a n s e c t s were l a i d a l o n g randomly 6,  chosen swaths i n f i e l d s 2, 3 and  i m m e d i a t e l y a f t e r the c r o p had been swathed by t h e f a r m e r s .  a l o n g a t r a n s e c t were g a t h e r e d from each f i e l d ; each sample was l e n g t h o f swath and as wide as the w i d t h o f swath  Ten samples a one meter  (a sample thus c o n s i s t e d  o f more t h a n t h r e e square meters o f s t a n d i n g c r o p ) .  The m a t e r i a l g a t h e r e d  was a i r - d r i e d , weighed and then t h r e s h e d i n the s t a t i o n a r y t h r e s h e r a t U.B.C. Seed was  c l e a n e d w i t h the a i d o f hand s i e v e s and winnowing.  Seed was  then  weighed. 4.3.6.2  O b s e r v a t i o n s and R e s u l t s  S t a n d i n g crop y i e l d s are g i v e n i n T a b l e 4.3.6.1 and F i g u r e 4.3.6.1. There appears t o be a wide range i n y i e l d s between f i e l d s . t h e r e appears a wide range o f y i e l d s w i t h i n the f i e l d  For f i e l d  itself.  measurements are g i v e n i n T a b l e 4.3.6.2 and F i g u r e 4.3.6.2.  6  Seed weight Seed w e i g h t s  f o l l o w c l o s e l y s t a n d i n g crop y i e l d s i n f i e l d s 2 and 3; however i n f i e l d seed y i e l d s are lower t h a n i n the o t h e r two f i e l d s d e s p i t e t h e  6  relatively  large y i e l d of standing crop. 4.3.6.3 D i s c u s s i o n By measuring t h e y i e l d s i n t h e swath I o b t a i n e d an a p p r o x i m a t i o n o f y i e l d s the farmer i s g e t t i n g from h i s combine.  However, t h r e s h i n g and  seed  71 T a b l e 4.3.6.1 E s t i m a t e s o f s t a n d i n g crop y i e l d s o b t a i n e d by s a m p l i n g swaths i n t h r e e C r e s t o n f i e l d s , August 1977. A i r dry yield kgs/ha  Mean  F i e l d 2 Eastman  2 760  69  7  11  55 -  F i e l d 3 Huscroft East  3480  87  12  14  64 - 107  F i e l d 6 Wyndell  5120  128  32  25  83 - 189  North  SD  CV%  Range 80  Number o f samples from swaths i n each o f t h r e e f i e l d s - 10.  T a b l e 4 .3.6.2 E s t i m a t e s of f i e l d seed y i e l d o b t a i n e d by s a m p l i n g swaths i n t h r e e C r e s t o n f i e l d s , August 1977 A i r dry yield kgs/ha  Mean  SD  CV%  Range  F i e l d 2 Eastman  324  8.1  1.2  15  6.5 - 10  F i e l d 3 Huscroft East  440  11.0  2.7  24  7.2 - 16  F i e l d 6 Wyndell  364  9.1  1.7  19  7.0 - 13  North  Number o f samples from swaths i n each o f t h r e e f i e l d s - 10. 2 Sample w e i g h t s i n gms. a i r d r y weight p e r 1/4 m .  F i g u r e 4,3.6.1  The v a r i a t i o n i n s t a n d i n g c r o p i n t h r e e C r e s t o n f i e l d s , August 1977: Ten samples from a swath i n each, f i e l d showing: a) b) c)  The a r i t h m e t i c mean f o r each f i e l d • The s i m p l e range by v e r t i c a l b a r ± one s t a n d a r d d e v i a t i o n from t h e mean by h o r i z o n t a l b a r s  72.  Creston: weight of top growth from swaths. 200  r  180 h  6  1 Field  F i g u r e 4.3.6.2  The v a r i a t i o n i n t h e w e i g h t o f seed from t h r e e f i e l d s i n C r e s t o n , August 1977: Ten samples from a swath i n each f i e l d showing: a) b) c)  The a r i t h m e t i c mean f o r each f i e l d • The s i m p l e range by v e r t i c a l b a r s ± one s t a n d a r d d e v i a t i o n from t h e mean by h o r i z o n t a l b a r s  73 CRESTON: Seed Weight From Swath  25,  S co  .£ 20[ 01  '3  15  10  3 Field  —i  6  74 c l e a n i n g methods d i f f e r .  I t was  n o t i c e d even a t time o f my  s a m p l i n g , many  heads were l o s t and c o n s i d e r a b l e s h a t t e r i n g o f seed pods took p l a c e ; t h e r e f o r e the y i e l d s p r e s e n t e d  i n T a b l e 4.3.6.2 a r e lower t h a n t r u e y i e l d s i n  the s t a n d i n g c r o p as measured by quadrat but show s i m i l a r 4.4  Sampling f o r N i t r o g e n F i x i n g A c t i v i t y  4.4.1  M a t e r i a l s and Methods Two  for  trends.  sampling  determining  fields.  The  based on t h a t used by H a l l i d a y and Pate  f o u r p l a n t - s o i l c o r e s were t a k e n w i t h the 10 cm.  the excess water was  from two  was  samples per f i e l d .  (2 c o r e s ) was  technique  n i t r o g e n f i x a t i o n r a t e s i n the C r e s t o n w h i t e c l o v e r seed  technique  For each f i e l d to make two  d a t e s were chosen u s i n g the a c e t y l e n e r e d u c t i o n  The  p l a c e d i n an a s s a y chamber. The  d i a . plugger  r o o t s were hand-washed w i t h c a r e  removed from t h e r o o t s w i t h paper t o w e l s .  l i t e r acid bottles.  (1976).  The  and  Each sample  a s s a y chambers were c o n s t r u c t e d  bottoms o f the a c i d b o t t l e s had been removed  and the edge ground on p l a t e g l a s s to make an a i r t i g h t s e a l when s t o p cock g r e a s e was  applied.  The  top o f the chamber was  f i t t e d w i t h a serum b o t t l e  s t o p p e r t h r o u g h which s y r i n g e n e e d l e s c o u l d pass.  Fifty millilitres  a c e t y l e n e were i n t r o d u c e d to g i v e a c o n c e n t r a t i o n o f 0.03 l a s t e d f o r f o u r hours and  T o t a l p l a n t n i t r o g e n was  and 4.3.2  Samples from the s t a n d i n g crop as d e s c r i b e d i n s e c t i o n s  and p r e c i s i o n o f the p r o c e d u r e was  4.4.2  tubes.  o b t a i n e d by use o f the method o f Chapman and  were used f o r d e t e r m i n i n g  composition  Incubation  f i v e m i l l i l i t r e samples o f "gas" were withdrawn  and p l a c e d i n seven m i l l i l i t r e v a c u t a i n e r  Pate (1961).  atm.  of  obtained  Observations  t o t a l p l a n t N.  A check on the  performed on s t a n d a r d  4.3.1  accuracy  samples o f known  from Canada Department o f A g r i c u l t u r e , Ottawa. and  Results  Samples from the a c e t y l e n e r e d u c t i o n t r i a l s have y e t t o be a n a l y z e d  for  75 ethylene. 4.4.1.  The r e s u l t s o f the t o t a l p l a n t n i t r o g e n f i x e d a r e g i v e n i n T a b l e  I t appears t h a t most a c t i v i t y i n f i x a t i o n o f a t m o s p h e r i c n i t r o g e n  f o r w h i t e c l o v e r under C r e s t o n c o n d i t i o n s , i n t h e c r o p ' s second y e a r , i s i n the  e a r l y p a r t o f the summer.  I t s h o u l d be o b s e r v e d t h a t i n some cases  t h e r e i s a n e t l o s s i n N i n t h e l a t t e r p a r t o f t h e growing 4.4.3  season.  Discussion The u s e o f g l a s s b o t t l e s as a s s a y chambers under f i e l d c o n d i t i o n s a t  C r e s t o n p r o v e d t o be clumsy and s l o w .  Chambers t h a t were more f l e x i b l e  w h i c h c o u l d be t a k e n onto t h e f i e l d would have been more p r a c t i c a l .  Plastic  bags as o u t l i n e d by Lee e t a l . (1977) would have been f a r more p r a c t i c a l . 4.5  Mowing T r i a l s  4.5.1  M a t e r i a l s and Methods F i e l d 6 was chosen f o r t h i s t r i a l and two l o c a t i o n s i n t h e f i e l d were  selected. meters  A t b o t h l o c a t i o n s on t h e 16th J u n e , 3 s t r i p s 3 f e e t wide and 10  l o n g were mown as c l o s e t o t h e ground as p o s s i b l e .  Spaced  between  mown s t r i p s were unmown s t r i p s one meter wide and h a l f a meter wide ively.  H a r v e s t i n g took p l a c e on t h e 5 t h August and 3 samples  ment, b o t h c u t and u n c u t , were t a k e n .  Samples were a i r - d r i e d ,  respect-  o f each  treat-  weighed and  threshed. 4.5.2  O b s e r v a t i o n s and R e s u l t s T o t a l w e i g h t o f the c u t areas was on an average 18% lower t h a n t h e  uncut a r e a s . the  Blossom numbers appeared fewer on t h e c u t a r e a .  Although a l l  samples were t h r e s h e d , t h e seed was found t o be i m p o s s i b l e t o s e p a r a t e  from t h e c o n c o m i t a n t m a t e r i a l . 4.5.3  Discussion Mowing i n t h e m i d d l e o f June was about a month t o o l a t e .  The crop was  i n the p r o c e s s o f b l o o m i n g and t h e t o t a l r e s u l t was a l o w e r i n g o f the t o p growth y i e l d s and numbers o f b l o s s o m s .  I f mowing i s t o be u n d e r t a k e n t o  76  Table 4.4.1 Y i e l d o f N. i n kgs/ha f o r standing crops i n 6 Creston f i e l d s . Field 1  2  3  4  5  Location WS  E  HE  HW  0  WN  30-5-77  Date:  5-8-77**  1  109.4  19Q.6  2  110.9  1Q6.1  3  100.2  106.9  4  125.3  137.6  1  43.5  74.1  2  60.2  71.6  3  60.2  117.4  4  49.2  66.5  1  77.0  135.0  2  71.2  143.4  3  49.7  139.1  4  70.6  106.1  1  68.3  116.0  2  33.9  116.7  3  76.5  183.7  4  67.8  81.4  1  139.1  211.2  2  121.3  167.8  3 6  Date:  90.5  78.1  4  109.3  141.3  1  122.3  285.1  2  103.8  91.0  3  144.9  156.6  4  113.8  125.1  * K j e l d a h l determination ** T o t a l n i t r o g e n i n c l u d e s a l l t o p growth i n c l u d i n g seed. n i t r o g e n t a k e n from s t a n d a r d t a b l e s by M i l l e r (1958).  The seed  77 reduce v e g e t a t i v e growth i n f a v o u r o f seed p r o d u c t i o n i t s h o u l d be done no l a t e r than t h e end o f May i n t h e C r e s t o n V a l l e y . 4.6  Coated Seed T r i a l The c o a t i n g o f c l o v e r and o t h e r seeds t o improve e s t a b l i s h m e n t has been  i n existence f o r several years. developed  The method used f o r t h e C r e s t o n t r i a l s was  i n A u s t r a l i a and New Zealand as a means o f i n o c u l a t i n g  c l o v e r seed.  white  The e x p e c t a t i o n i s t h a t g r e a t e r numbers o f t h e r h i z o b i a w i l l  be r e t a i n e d on t h e coated seed and t h a t t h e i r s u r v i v a l i s i n s u r e d up t o t h e time o f p l a n t i n g .  The p r o c e s s i s no l o n g e r c o n f i n e d t o legumes and i s  becoming a p o p u l a r means o f a p p l y i n g p l a n t n u t r i e n t s t o t h e seeds o f many crop s p e c i e s . 4.6.1  M a t e r i a l s and Methods The t r i a l was undertaken  on t h e M u l l i g a n farm.  The seed used was o f  C r e s t o n o r i g i n and t h e c o a t i n g p r o c e s s was done by C e l P r i l I n d u s t r i e s Inc.,  Manteca, C a l i f o r n i a .  On t h e 16th June t h e t r i a l was l a i d o u t and  seeded on a t h r e e by t h r e e L a t i n square d e s i g n ; each u l t i m a t e p l o t was t h r e e meters by t h r e e meters.  Treatments were a) c o a t e d seed, b) s t a n d a r d  i n o c u l a t i o n , c) n o t i n o c u l a t e d (see t r i a l a t U.B.C. s e c t i o n 4.11). 4.6.2  Observations  and R e s u l t s  R a i n f a l l a f t e r s e e d i n g was i n s u f f i c i e n t t o produce a good e s t a b l i s h m e n t ; consequently 4.7 4.7.1  t h e t r i a l was abandoned.  Fertilizer  Trial  M a t e r i a l s and Methods The  t r i a l was undertaken  of Creston o r i g i n .  on t h e M u l l i g a n farm.  On t h e 16th o f June t h e t r i a l was l a i d out i n a s p l i t  p l o t design with three r e p l i c a t i o n s . The  Seed f o r t h i s t r i a l was  Each p l o t was two meters by two meters.  t r i a l was a l s o seeded on t h e 1 6 t h June.  The f o l l o w i n g were t h e treatments  78 and i n each r e p l i c a t i o n , each t r e a t m e n t had an u n t r e a t e d a d j a c e n t p l o t : a)  N i t r o g e n a t 100 kgs p e r h e c t a r e  b)  S u l f u r at  10 kgs p e r h e c t a r e  c)  Boron a t  2 kgs p e r h e c t a r e  d)  Molybdenum a t 1 kg p e r h e c t a r e  e)  Calcium at  70 kgs p e r h e c t a r e  f)  Nitrogen at  65 kgs p e r h e c t a r e  Phosphorous a t 80 kgs p e r h e c t a r e  Potassium  at  50 kgs p e r h e c t a r e  (K 0) 2  4.7.2  Observations  and R e s u l t s  R a i n f a l l a f t e r s e e d i n g was the t r i a l was 4.8  i n s u f f i c i e n t t o produce a s t a n d ;  consequently  abandoned.  Sampling f o r Cyanogenesis i n C r e s t o n White C l o v e r  4.8.1  M a t e r i a l s and Methods ' On t h e 1 s t J u l y a l l f i e l d s were sampled f o r c y a n o g e n e s i s .  hours 5 samples each o f  150 mg.  f i e l d , were p l a c e d i n 10 mm  At 09:00  o f l e a f t i s s u e , from each l o c a t i o n i n each  x 120 mm  t e s t tubes.  Samples were b r u i s e d , 10  drops o f c h l o r o f o r m added, a s t r i p o f p i c r a t e paper was and h e l d i n p l a c e by a r u b b e r s t o p p e r .  p l a c e d i n the tube  Samples were i n c u b a t e d f o r 24 hours  at 22°C. 4.8.2  Observations No r e a c t i o n was  4.8.3  and R e s u l t s observed  a f t e r 24 hours i n any sample from C r e s t o n .  Discussion T h i s would then agree w i t h Daday's (1954 b and c) o b s e r v a t i o n s on  decrease  i n numbers o f w h i t e c l o v e r p l a n t s g i v i n g a cyanogenic r e a c t i o n  the  79 where t h e r e i s a decrease i n t h e average J a n u a r y B. 4.9  Studies  Undertaken a t t h e U n i v e r s i t y o f B.C.  S t r a i n E v a l u a t i o n U s i n g Groups o f S i n g l e  4.9.1  isotherm.  Plants  G e n e r a l Comments on E x p e r i m e n t a l D e s i g n and Layout Seeds were o b t a i n e d  from B u c k e r f i e l d s L t d . , Vancouver, B.C, t h e C e n t r a l  E x p e r i m e n t a l Farm, A g r i c u l t u r e Canada, Ottawa, and t h e S t a t e U n i v e r s i t y o f Oregon, C o r v a l l i s , Oregon.  Twenty s e p a r a t e s t r a i n s o r l o t s were g a t h e r e d ;  T a b l e 4.9.1.1 g i v e s t h e o r i g i n s and 1000 seed w e i g h t s . Creston are a l l designated trials  as Canada No. 1 seed.  came from l o t s h a r v e s t e d  Seed l o t s from  Seed l o t s used i n my  on i n d i v i d u a l farms; seed f o r grower p l a n t -  i n g s may w e l l have come from o t h e r growers i n t h e C r e s t o n a r e a b u t i t i s u n l i k e l y t h a t much seed i n r e c e n t y e a r s has come from o u t s i d e o f t h e C r e s t o n area. Seeds were p l a n t e d as i n d i v i d u a l s i n t h e greenhouse on March 4, 1977. On t h e 26th A p r i l they were moved t o t h e c o l d frames f o r h a r d e n i n g o f f . In May t h e f i e l d s i t e was p r e p a r e d a t U.B.C. and a b a s i c a p p l i c a t i o n o f commercial f e r t i l i z e r was a p p l i e d . kgs/ha P ° ) 2  a  n  5  d  1 4 2  The r a t e s o f 350 kgs/ha 0-20-0 (70  kgs/ha 0-0-60 (85 kgs/ha K 0 ) were used. 2  P l a n t s were e s t a b l i s h e d i n t h e f i e l d on t h e 5 t h and 6 t h May a t a spacing  o f 65 cms between p l a n t s and 1 meter between rows o f 5 p l a n t s .  twenty s t r a i n s were a t random i n each o f f o u r b l o c k s ; each s t r a i n was r e p r e s e n t e d  ments and o b s e r v a t i o n s  o f 20 i n d i v i d u a l p l a n t s p e r s t r a i n .  The  Measure-  were made on i n d i v i d u a l p l a n t s .  V a r i a t i o n i n Flowering  4.9.2.1  therefore  by f i v e p l a n t s i n u l t i m a t e p l o t s and i n f o u r b l o c k s t o  give a t o t a l representation  4.9.2  The  by Date  M a t e r i a l s and Methods assessment o f f l o w e r i n g was done by c o u n t i n g  t h e number o f i n f l o r -  80  T a b l e 4.9.1.1 Weight o f seed from twenty s t r a i n s o f w h i t e c l o v e r p l a n t e d a t u.  B.C.:  weight i n grams f o r 1000 seeds f o r  eachi s t r a i n .  Strain  Origin  A (Piper)  Creston  0. 7774 grams  B (Ordek)  Creston  0. 6020 grams  C (O.C. Ranch)  Creston  0. 7639 grams  D (Huscroft)  Creston  0. 7553 grams  E (Moon)  Creston  0. 7417 grams  G (Stager)  Creston  0. 7662 grams  H (Staples)  Creston  0. 7586 grams  K (Ogilvie)  Creston  0. 8005 grams  L (Sutcliffe)  Creston  0. 7314 grams  M (Barbian)  Netherlands  0.,6232 grams  0 (Pertina)  Netherlands  0.,7379 grams  P (Tohoku)  Japan  0.,4799 grams  R (Kivi)  Germany  0.,6782 grams  S (Daenok)  Denmark  0.,7959 grams  U (Pajberg)  Denmark  0.,6658 grams  T (L51-6-40)  Louisiana  0..5708 grams  V (L75-614-S1)  Louisiana  0,.6217 grams  W (L51-6LAWC-50)  Louisiana  0,.6142 grams  X (L081-007-1344)  Louisiana  0,.5999 grams  Y (L081-007-2675)  Louisiana  0 .6002 grams  81 escences t h a t had a t l e a s t one f l o r e t i n f u l l bloom on each p l a n t . t i o n o f f l o w e r i n g took p l a c e on t h r e e d a t e s :  Observa-  June 8 t h , June 22nd and J u l y  19th. 4.9.2.2  O b s e r v a t i o n s and R e s u l t s  The F - t e s t i n t h e a n a l y s i s o f v a r i a t i o n suggest d i f f e r e n c e s between s t r a i n s and between d a t e s .  The o b s e r v a t i o n s a r e l i s t e d i n T a b l e s 4.9.2.1  4.9.2.2 and 4.9.2.3 and F i g u r e s 4.9.2.1, 4.9.2.2 and 4.9.2.3.  T a b l e 4.9.2.1  g i v e s t h e mean number o f heads i n f l o w e r p e r p l a n t by s t r a i n and t h e p e r centage o f p l a n t s w i t h o u t blossoms by d a t e .  The s t r a i n s a r e r a n k e d ; a  s t r a i n o f c o u r s e w i l l n o t n e c e s s a r i l y have t h e same rank on each d a t e . T a b l e 4.9.2.2 d i s p l a y s t h e o c c u r r e n c e o f t h e same s t r a i n s w i t h i n a rank through t h e two f o l l o w i n g d a t e s :  June 22nd and J u l y 1 9 t h .  A prominent  f e a t u r e i s t h a t t h e e a r l y b l o s s o m i n g p l a n t s and s t r a i n s t e n d t o bloom more p r o f u s e l y throughout t h e season; p l a n t s and s t r a i n s p r o d u c i n g few o r no blossoms  e a r l y i n t h e season t e n d s t r o n g l y t o c o n t i n u e t o remain v e g e t a t i v e  and poor  bloomers.  Tables 4.9.2.1, 4.9.2.2 and 4.9.2.3 i l l u s t r a t e t h e f l o w e r i n g a t U.B.C. f o r t h e twenty s t r a i n s .  response  A l l of the s t r a i n s of Creston o r i g i n  rank w i t h i n t h e f r e e f l o w e r i n g t w e l v e s t r a i n s through t h e f l o w e r i n g season. 4.9.2.3  Discussion  F l o w e r i n g o f t h e w h i t e c l o v e r p l a n t i s a response t o a c o m b i n a t i o n o f temperature and day l e n g t h .  Crowder (1960) observed t h a t s t r a i n s o f w h i t e  c l o v e r from t h e more n o r t h e r n o r s o u t h e r n l a t i t u d e s would n o t f l o w e r f r e e l y under h i s c o n d i t i o n s i n Colombia.  On t h e o t h e r hand my t r i a l s r e v e a l e d t h a t  the two s t r a i n s o f warmer l a t i t u d e s d i d n o t f l o w e r as f r e e l y as t h o s e from the c o o l e r l a t i t u d e s .  Free f l o w e r i n g s t r a i n s a r e i m p o r t a n t f o r seed produc-  t i o n and t h e C r e s t o n s t r a i n s , compared t o t h e r e m a i n i n g s t r a i n s , a r e cons i d e r e d t o be good seed p r o d u c e r s .  T a b l e 4.9.2.1. Twenty s t r a i n s grown a t U.B.C. ranked a c c o r d i n g t o average blossom number p e r p l a n t and percentage o f p l a n t s without blossoms Rank: 1 -5  f o r three dates  Rank: 6 - 10  Rank: 11 -15  Rank: 16- 20  Date 8-6 Strain  A  U  C  0  G  M  B  L  S  D  R  K  H  P  E  W  V  Mean Blossom #/plant  .95  .85  .75  .50  .45  .45  .35  .35  .35  .33  .20  .20  .15  .10  .05  .05  .05  % No Blossoms  60  75  65  70  85  70  80  85  80  73  70  85  95  90  95  95  95  Y .00  X  T  .00  .00  100  100  100  V  X  T  0.00  0.00  Date 22-6 Strain  B  D  Mean Blossom #/plant  3.25  2.95  % No. Blossoms  20  27  U 2.40  50  E 2.35  40  H 2.20  65  P  L  S  G  A  R  K  2.0  1.65  1.65  1.5  1.4  1.00  0.70  25  65  45  60  70  65  70  C 0.70  60  W  M  0.60  0.50  80  85  .  0 0.50  80  Y 0.35  80  0.05  95  100  100  Date 19-7 Strain  B  U  . H  L  W  A  D  Y  Mean Blossom #/plant  28.55  24.25  23.70  22.30  21.30  20.95  20.33  20.05  20  10  10  % No. Blossoms  0  5  10  5  5  K  C  X  19.75' 16.15  15.50  13.95  13.65  12.9  12.85  15  15  20  25  10  10  E  G  30  P  M  S  T  V  0  12.7  12.20  11.70  11.50  6.40  35  25  R  5  30  25  F i g u r e 4.9.2.1  The response i n f l o w e r i n g hy twenty •':': s t r a i n s o f w h i t e c l o v e r on t h e 8-6-77; t h e twenty s t r a i n s a t random i n each o f f o u r b l o c k s ; each s t r a i n r e p r e s e n t e d by five plants i n ultimate p l o t s ; ultimate p l o t s l o c a t e d a t random w i t h i n each b l o c k . The C r e s t o n s t r a i n s r e p r e s e n t e d hatched v e r t i c a l l i n e .  by a  The o t h e r non C r e s t o n s t r a i n s r e p r e - : "', sented by a s o l i d v e r t i c a l l i n e .  U . B . C . - M e a n N o . Of F l o w e r s P e r P l a n t O n S t r a i n s Of C r e s t o n O r i g i n  8-6-77  I  P e r c e n t a g e Of P l a n t s W i t h N o I n f l o r e s c e n c e  •  O  O  1.0  Z  •  c o  0) 3  •  #  •  #  #  #  •  •  •  •  •  0.5  Ol  M00%  50%  A  U  C  O  G  M  B  L  S  D  R  STRAIN  K  i_L H  J P  E  I W  L V  Y  X  T  F i g u r e 4.9.2.2  The response i n f l o w e r i n g by twenty s t r a i n s o f w h i t e c l o v e r on t h e 22-6-77; t h e twenty s t r a i n s a t random i n each o f f o u r b l o c k s ; each, s t r a i n r e p r e s e n t e d by five plants i n ultimate p l o t s ; ultimate p l o t s l o c a t e d a t random w i t h i n each b l o c k . The C r e s t o n s t r a i n s r e p r e s e n t e d hatched v e r t i c a l l i n e .  by a  The o t h e r non-Creston s t r a i n s r e p r e sented by a s o l i d v e r t i c a l l i n e .  3.o r  i3.3  U . B . C - Mean No. Of Flowers Per Plant On 22-6-77 Strain Of Creston Origin \ Percentage Of Plants With No Inflorescence •  2.0  o  o Z c o H00°/o  1.0 •  t  •  r-50%  E  oi  L-0% B  U  H  S  O  A  STRAIN  R  K  C  W  M  O  oO  Figure  4.9.2.3  The response i n f l o w e r i n g by twenty s t r a i n s o f w h i t e c l o v e r on t h e 19-7-77; t h e twenty s t r a i n s a t random i n each o f f o u r b l o c k s ; each s t r a i n r e p r e s e n t e d by five plants i n ultimate plots; ultimate p l o t s l o c a t e d a t random w i t h i n each b l o c k . The C r e s t o n s t r a i n s r e p r e s e n t e d hatched v e r t i c a l l i n e .  by a  The o t h e r non-Creston s t r a i n s r e p r e sented by a s o l i d v e r t i c a l l i n e .  30  U . B . C - Mean No. Of Flowers Per Plant On 19-7-77 Strains Of Creston Origin i Percentage Of Plants With No Inflorescence •  20  o 6  Z c o M00%  10  i  •  t ±  m  •  0'  B  U  H  •  t  • i-0% M  W  STRAIN  00  5T  86  T a b l e 4.9..2. 2 Relationship of earliness i n flowering inflorescences  t o t h e number o f  produced; o c c u r r e n c e o f number o f  s t r a i n s w i t h i n r a n k s f o r two d a t e s . Date 19/7 Rank  1-5  6-10  11-15  16-20  1- 5  3  2  0  0  Date  6-10  1  2  1  1  22/6  11-15  1  3  1  16-20  0  1  3  0 1  Ranks c o r r e s p o n d t o o r d e r w i t h i n a s c a l e o f twenty.  87 4.9.3  V a r i a t i o n i n Leaf Area  4.9.3.1  M a t e r i a l s and Methods  C o l l e c t i o n s o f l e a v e s and p e t i o l e s were made on J u l y 20th and October 13th.  C o l l e c t i o n s were made by t a k i n g t h e t h i r d open l e a f and p e t i o l e  from t h e end o f a s t o l o n and another l e a f and p e t i o l e from t h e c e n t r e o f the p l a n t .  These samples were c o n s i d e r e d new and o l d r e s p e c t i v e l y .  The  t r i f o l i a t e l e a f a r e a e s t i m a t e s were made u s i n g premeasured l e a v e s as o u t l i n e d by W i l l i a m s e t a l . (1964). 4.9.3.2  Observations  A r e a e s t i m a t e d was i n square c e n t i m e t e r s .  and R e s u l t s  The r e s u l t s from t h e samples t a k e n on two dates a r e found i n T a b l e s 4.9.3.1 and 4.9.3.2. and 4.9.3.2.  The r e s u l t s a r e a l s o p o r t r a y e d i n F i g u r e s 4.9.3.1  The F - t e s t i n t h e a n a l y s i s o f v a r i a t i o n suggests  significant  d i f f e r e n c e s , between s t r a i n s and between dates f o r l e a f a r e a . 4.9.3.3  Discussion  Mature l e a v e s produced l a t e r i n t h e season a r e s m a l l e r than produced e a r l i e r . (1963) .  those  These r e s u l t s a r e s i m i l a r t o t h o s e r e p o r t e d by B e i n h a r t  I n t h e C r e s t o n s t r a i n s t h e r e i s as g r e a t a range i n v a r i a b i l i t y as  i n other s t r a i n s ; the l e a f area  means f o r C r e s t o n s t r a i n s show  Creston white c l o v e r s t r a i n s are indeed i n t e r m e d i a t e . Netherlands  i s more o f a;. : w i l d - "type.  i n contingency t a b l e s .  that the  S t r a i n "M" from t h e  Comparative i n f o r m a t i o n i s p r o v i d e d  The l a r g e C h i - s q u a r e v a l u e s suggest  that l e a f area  d i f f e r e n c e s a r e n o t random d i f f e r e n c e s under t h e c o n d i t i o n s o f t h i s but a r e a s s o c i a t e d by s t r a i n . be governed by e n v i r o n m e n t a l  trial  K i n g (1961) found d i f f e r e n c e i n l e a f a r e a t o factors.  A n o t h e r i n t r e s t i n g f e a t u r e i s t h e i n c r e a s e i n l e a f a r e a , by t h e L o u i s i a n a s t r a i n s , f o r t h e f a l l grown m a t e r i a l . i n carbohydrate  storage.  T h i s c o u l d be a f a c t o r  88 T a b l e 4.9.3.1  Leaf a r e a i n square c e n t i m e t e r s f o r i n d i v i d u a l p l a n t s i n twenty s t r a i n s grown i n a u n i f o r m n u r s e r y a t U.B.C. Sampling d a t e 20-7-77Cl) No. l e a v e s Strain  Source  ;.per sample.  Mean  SD  CV%  Range  A  Creston  40  14.5  4.4  30  8  B  Creston  40  14.0  5.0  36  6.3 - 20  C  Creston  40  14.7  4.6  31  6.3-25.1  D  Creston  30  14.9  5.2  35  6.3-25.1  E  Creston  38  15.0  5.3  35  6.3-25.1  G  Creston  40  13.0  4.7  36  6.3 - 25.1  H  Creston  40  14.9  4.1  28  8  K  Creston  40  14.7  4.5  31  L  Creston  40  14.2  4.0  28  8  - 20  M  Netherlands  40  7.7  2.3  30  4  - 15.8  0  Netherlands  40  14.7  4.8  33  6.3-25.1  P  Japan  40  18.0  5.3  29  6.3 - 29  R  Germany  40  10.8  3.8  35  6.3 - 20  S  Denmark  40  15.6  4.3  28  8  - 25.1  U  Denmark  40  13.1  4.9  37  5  - 25.1  T  Louisiana  40  12.9  4.1  32  4 - 2 0  V  Louisiana .  40  12.0  3.2  27  5 - 2 0  W  Louisiana  40  11.4  4.1  36  6.3 - 20  X  Louisiana  40  15.3  4.1  27  8  Y  Louisiana  40  12.9  3.8  29  6.3-25.1  - 20  - 25.1 8 - 2 0  - 25.1  Figure  4.9.3.1  The v a r i a t i o n i n l e a f a r e a on t h e 2 0 - 7 - 7 7 ( l ) f o r twenty s t r a i n s a t random i n each o f f o u r b l o c k s ; each s t r a i n r e p r e s e n t e d by f i v e p l a n t s i n u l t i m a t e p l o t s ; u l t i mate p l o t s l o c a t e d a t random w i t h i n each b l o c k , showing: a) b) c)  The a r i t h m e t i c mean f o r each s t r a i n • The s i m p l e range by v e r t i c a l b a r ± one s t a n d a r d d e v i a t i o n from t h e mean by h o r i z o n t a l b a r s  30  r  130  U . B C . P l o t : leaf a r e a 1  25  25  H20  20\  E U  15  15  10  10  c < UJ  <  A  B  C  D  E  G  H  • Crest.  ,  K  L  J  M v  O . Neth.  P  R  I \ „ Iv  S  ,  J a . Ger.  *  U  T  ,  /  Den.  V v  W  X -V  Y y  Louis.  CO STRAIN  5T*  90 T a b l e 4.9.5.2  Leaf a r e a i n square c e n t i m e t e r s f o r i n d i v i d u a l , p l a n t s : i n twenty s t r a i n s o f w h i t e c l o v e r grown i n a u n i f o r m n u r s e r y a t U.B.C. Sampling d a t e 13-10-77(2) •ain  Source  A  Creston  B  No. l e a v e s p e r sample'  Mean  SD  ' CV%  Range  20  7.5  2 .3  31  4  - 12,,6  Creston  20  8.4  2 .3  27  5  - 12.,6  C  Creston  20  9.3  2 .8  30  5  - 15.,8  D  Creston  10  9.6  2 .0  21  6,.3 - 12..6  E  Creston  18  6.4  2 .7  42  2,.5 - 12.,6  G  Creston  20  8.2  2 .5  30  5  H  Creston  20  9.5  1 .9  20  6..3 - 12..6  K  Creston  18  8.1  2 .7  33  6..3 - 15,.8  L  Creston  20  7.2  2 .2  31  2  - 10  M  Netherlands  20  4.5  1 .5  33  2  -  0  Netherlands  20  8.2  3 .0  37  4  - 15.,8  P  Japan  20  16.7  4 .0  24  10  - 25..1  R  Germany  U<  7.1  2 .5  35  3..2 - 10  S  Denmark  18  8.2  2 .6  32  6,.3 - 15..8  U  Denmark  20  6.5  2 .0  31  O ,  T  Louisiana  20  14.6  4 .7  32  6 .3 - 20  V  Louisiana  20  14.0  5 .6  40  5  W  Louisiana  20  12.8  5 .0  39  6 .3 - 20  X  Louisiana  20  13.1  4 .4  34  4  Y  Louisiana  20  15.2  4 .4  29  10  T  - 12.,6  8  .2 - 12,.6  - 20  - 20 - 25 .1  F i g u r e 4,9.3.2  The v a r i a t i o n i n l e a f a r e a on t h e 13-10V77 (.2) f o r twenty s t r a i n s a t random i n each., of four b l o c k s ; e a c h . s t r a i n represented by f i v e p l a n t s i n u l t i m a t e p l o t s ; u l t i mate p l o t s l o c a t e d a t random w i t h i n each, b l o c k , showing: a) The a r i t h m e t i c mean f o r each s t r a i n • b) The s i m p l e range by v e r t i c a l b a r c), ± one s t a n d a r d d e v i a t i o n from t h e mean by h o r i z o n t a l b a r s  30  U.B.C. P l o t : l e a f a r e a  r  30  2  25  20  15  10  01  B  C  D  E Crest.  G  H  K  L  M  O Neth.  STRAIN  P Ja.  R Ger.  U  8 Den.  T  V  W  X  Y  Louis.  .9-  4.9.3.3  Table  Contingency t a b l e 2 L e a f Area (cm )  Total Strain  0 - 4 5 -  9  10 - 14 15 - 19  20  Total  on the 2 0 - 7 - 7 7 .  and Chi-square v a l u e s f o r average l e a f area f o r twenty s t r a i n s grown a t U.B.C; sampled  5  1  S  19  0  o  0  0  0  9  5  3  4  11  14  15  14  U  18  !  2  40  40  20 1  40  14  10 3  30  17 3  38  12 2  0  18  0  12  . 19 1  40  40  0  2  0  0  0  0  0  5  29  4  1  16  1  7  14  10  15  8  20  20  20  2  0  0  40  40  40  -Creston  Actual x  2  = 257.18**  2  40  Netherlands M O  Expected X _ 2  0 5 ( 7 6 )  =  9 7  -  3 4  . 18  21  8  15  6  0  40  40  Ja P  Ge R  17  22  2  15  1  40  S  2  0 5  6  20  26  13  0  40  Denmark U  0  17  V  0  2  4  15  24  9  0  40  0 14  8  40  T  0  21  2  40  -LouisianaW X  11  1  40  139  312 302  31  40  788  w  T a b l e 4.9.3.4 Contingency t a b l e and Chi-square v a l u e s f o r average l e a f a r e a f o r twenty s t r a i n s grown a t U.B.C.; sampled L e a f Area  ,2, (cm )  Total  Strain-  1  4  0 - 4  2  5 - 9  15  11  10-14  3  8  6  0  15-19  0  0  1  0  1  20 -  0  0  10  12  4  4  0  13  7  0  9  2  11  '  20  0  0  0  20  20  10  0 0  2  =317.05**  10  7  0  1  3  0  13  0  0  5  1  0  4  0  1  0  0  0  1  18  0  14  7  0  8  1  12  0  1  0  0  0  0  0  20  18  18  20  20  Ja P  Ge R  9  9  9  12  0  27  0  175  10  125  8  50  20  382  0 0  18  -Creston c n  Actual x  10  15  11  /  0  Total  on the 13-10-77.  0  20  0  20  H  0  18  0  20  K  2 Expected x "  L  0 > 0 5 ( 7 6 )  0  20  20  Netherlands M 0  = 97.34 = 97  Denmark S U  20  20  20  --Louisiana V  W  X  94 The method by W i l l i a m s et al_. (1964) f o r e s t i m a t i o n s o f l e a f  area  p r o v e d t o be a p r a c t i c a l and q u i c k method o f a s s e s s i n g l e a f a r e a i n the field.  Although  the method i s designed  t o a l l o w f o r l e a f shape, the  g r e a t e s t d i f f i c u l t y appeared when a b n o r m a l l y 4.9.4  l o n g l e a v e s were encountered.  V a r i a t i o n i n P e t i o l e Length  4.9.4.1 The  M a t e r i a l s and Methods same samples taken f o r l e a f a r e a s e r v e d f o r the measurement o f  p e t i o l e length.  The p e t i o l e l e n g t h s were measured i n c e n t i m e t e r s  from the  base o f the p e t i o l e at the j u n c t i o n o f the s t i p u l e s and p e t i o l e t o the j u n c t i o n o f the l e a f p e d i c e l s . 4.9.4.2 The  Observations  and  Results  F - t e s t i n the a n a l y s i s o f v a r i a t i o n suggest d i f f e r e n c e s between  s t r a i n s and between dates f o r p e t i o l e l e n g t h .  The  r e s u l t s of p e t i o l e  l e n g t h measurements are shown i n T a b l e 4.9.4.1 and 4.9.4.2. noteworthy t h a t l e n g t h d e c r e a s e s i n the f a l l .  The  I t i s again  Louisiana strains  again  have the l o n g e r p e t i o l e s . Tables  4.9.4.3 and 4.9.4.4 r e l a t e l e a f a r e a and p e t i o l e l e n g t h f o r b o t h  f u l l y grown l e a v e s and p e t i o l e s t o l e a f a r e a and p e t i o l e l e n g t h f o r younger l e a v e s and p e t i o l e s f o r two dates o f o b s e r v a t i o n .  The  correlation  coef-  f i c i e n t s i l l u s t r a t e t h a t the d i f f e r e n c e s i n growth o f l e a v e s and p e t i o l e s are r e l a t i v e l y independent w i t h i n the i n t e r m e d i a t e form o f w h i t e c l o v e r . 4.9.4.3  Discussion  The work done by Denne (1966) and by Brougham (1966) t r a c e s the expans i o n and h i s t o r y o f a r e a and canopy.  l e n g t h o f l e a v e s and p e t i o l e s i n the w h i t e  clover  C o n t i n u a l growth makes f o r u n r e l i a b l e measurements ( o r confounding)  when samples are not c o r r e l a t e d w i t h age; and 4.9.4.4 supports  these  observations.  the i n f o r m a t i o n i n T a b l e s  4.9.4.3  Table -UK4.1 p e t i o l e l e n g t h i n c e n t i m e t e r s f o r i n d i v i d u a l p l a n t s i n twenty s t r a i n s grown i n a u n i f o r m n u r s e r y a t U.B,. C , sampl i n g date 20-7- 77 No. p e t i o l e s rain  Source  per sample.  Mean  SD  CM  Range  A  Creston  40  21..75  5.26  24  13-30  B  Creston  40  23..18  4.13  18  14-31  C  Creston  40  20..58  5.33  26  12-34  D  Creston  30  20..97  6.23  30  11-33  E  Creston  38  20..76  5.12  25  G  Creston  40  20..75  5.07  24  H  Creston  40  22..03  5.46  25  K  Creston  40  22..25  5.25  24  12-35  L  Creston  40  23..18  5.53  24  15-34  M  Netherlands  40  17..75  4.68  26  9-26  0  Netherlands  40  19..88  4.36  22  13-28  P  Japan  40  23..48  6.50  28  14-40  R  Germany  40  20..33  5.44  27  11-33  S  Denmark  40  20,.15  4.69  23  10-30  U  Denmark  40  19,.83  5.99  30  9-34  T  Louisiana  40  23,.28  4.91  21  15-34  U  Louisiana  40  21,.30  5.89  28  9-35  W  Louisiana  40  21,.63  5.84  27  13-34  X  Louisiana  40  22 .75  5.37  24  11-34  Y  Louisiana  40  23,.50  5.46  23  13-36  8-31 10-30 8-31  96 Table"4.9.4.2.'' Avg. p e t i o l e l e n g t h i n c e n t i m e t e r s f o r i n d i v i d u a l p l a n t s i n twenty s t r a i n s grown i n a u n i f o r m n u r s e r y a t U.B.C, sampling date 13-10-77 Xc. p e t i o l e s ' Strain  Source  p e r sample-  Mean  SD  CV%  Range  A  Creston  20  14.45  3.41  24  7-21  B  Creston  20  13.85  4.18  30  6-21  C  Creston  20  15.78  5.24  33  7-25  D  Creston  10  14.50  2.80  19  11-20  E  Creston  18  11.40  4.60  40  4-21  G  Creston  20  13.95  4.11  29  6-22  H  Creston  20  16.85  3.76  22  10-23  K  Creston  18  15.78  4.35  28  9-24  L  Creston  20  13.55  3.38  25  7-20  M  Netherlands  20  10.40  3.39  33  5-17  0  Netherlands  20  13.55  4.89  36  5-23  P  Japan  20  20.05  5.75  29  12-29  R  Germany  18  12.39  4.80  39  6-24  S  Denmark  18  13.39  2.57  19  9-19  U  Denmark  20  11.00  3.34  30  7-19  T  Louisiana  20  17.90  5.19  29  11-25  U  Louisiana  20  17.90  5.59  31  10-28  W  Louisiana  20  17.85  5.71  32  8-28  X  Louisiana  20  18.30  6.61  36  7-29  Y  Louisiana  20  21.30  5.03  24  13-30  T a b l e 4.9.4.3 R e l a t i o n s h i p o f l e a f a r e a t o p e t i o l e l e n g t h ; measurements t a k e n on 20-7-77 f o r twenty s t r a i n s grown i n a u n i f o r m n u r s e r y a t U.B.C. Strain  F u l l y grown l e a v e s and p e t i o l e s Linear Regression Correlation _ Equation Coefficient Y = 19.86 + 0.29X r = 0.34  Origin  A  Creston  B  Creston  C  Creston  D  r = 0.30  Creston  Y = 24.21 + 0.08X Y = 14.62 + 0.59X Y  E  Creston  Y = 16.12 + 0.49X  G  Creston  H  r = 0.09  Younger l e a v e s and p e t i o l e s Linear Regression Correlation Equation Coefficient Y = 10.89 + 0.51X  r = 0.68*  Y = 22.32 - 0.09X  r = -0.07  Y = 8.14 + 0.61X  r = 0.79**  y =  r =  r = 0.57  Y = 8.39 + 0.54X  Y = 21.95 + 0.12X  r = 0.58  r = 0.13  Y = 18.07 + 0.01X  Creston  Y = 23.32 + 0.10X  r = 0.01  r = 0.14  Y = 8.46 + 0.64X  K  Creston  Y  r = 0.60  r = 0.29  Y = 9.55 + 0.62X  L  Creston  Y  r = 0.69*  21.66  + 0.25X  r = 0.25  Y = 18.04 + 0.11  M  Netherlands  Y  r = 0.18  17.39  + 0.42X  r = 0.21  Y = 10.49 + 0.51  0  Netherlands  Y  r = 0.34  16.40  + 0.47X  r = 0.77**  Y = 15.92 + 0.01  P  Japan  Y  r = 0.04  26.32 + 0.14X  r = 0.17  Y = 20.64 - 0.01  R  Germany  Y •• 17.43  r = -0.01  + 0.54X  r = 0.63  Y = 16.21 + 0.11  S  Denmark  Y=  r = 0.18  + 0.38X  r = 0.35  Y = 16.09 + 0.12  U  Denmark  Y = 9.70 + 0.76X  r = 0.42  r = 0.75*  Y = 10.78 + 0.40  T  Louisiana  Y = 15.84  r = 0.55  + 0.68X  r = 0.55  Y = 15.19 + 0.35  V  Louisiana  Y=  r = 0.50  22.88 + 0.11X  r = 0.11  Y = 23.59 - 0.28  W  Louisiana  Y  r = 0.33  24.46 + 0.11X  r = 0.09  Y = 12.89 + 0.45  X  Louisiana  Y = 23.64 + 0.12X  r = 0.64*  r = 0.13  Y = 9.77 + 0.60  Y  Louisiana  Y = 28.03 - 0.002X  r = 0.52  r = -0.002  Y = 26.04 - 0.58  r = 0.39  •• 20.04 + 0.39X  :  18.22  Leaf a r e a - X; P e t i o l e l e n g t h - Y; Sample s i z e - 10 o b s e r v a t i o n s p e r t r e a t m e n t r.05(8) = 0.6319* r.01(8) = 0.7646**  T a b l e 4.9. 4.4 R e l a t i o n s h i p o f l e a f a r e a t o p e t i o l e l e n g t h ; measurements t a k e n t h e 13-10-77 f o r t w e n t y s t r a i n s grown i n a u n i f o r m n u r s e r y a t U.B.C. F u l l y grown l e a v e s and Strain  petioles Correlation Coefficient  Younger l e a v e s and p e t i o l e s Correlation Regression equation v j u c t i n—LC11 L  Origin  Regression  A  Creston  Y = 9.60 + 0.92X  r = 0.72*  Y = 5.18 + 0.96X  B  Creston  r = 0.80**  Y = 5.61 + 1.37X  r = 0.77**  Y = 3.84 + 0.84X  C  Creston  r = 0.71*  Y = 13.61 + 0.59X  r = 0.41  Y = 9.25 + 0.34X  D  Creston  r = 0.27  E  Creston  Y = 4.75 + 1.39X  r = 0.77**  Y = 3.25 + 0.94X  G  Creston  r = 0.76*  Y = 8.36 + 0.94X  r = 0.74*  Y = 4.57 + 0.89X  H  Creston  r = 0.55  Y = 12.53 + 0.75X  r = 0.49  Y = 13.50 + 0.05X  K  Creston  r = 0.50  Y = 7.30 + 1.25X  r = 0.71  Y = 11.41 + 0.30X  L  Creston  r = 0.24  Y = 7.87 + 1.03X  r = 0.84**  Y = 4.42 + 1.02X  M  r = 0.69*  Netherlands  Y = 6.72 + 1.30X  r = 0.65*  Y = 3.40 + 1.08X  0  r = 0.81**  Netherlands  Y = 9.22 + 0.75X  r = 0.60  Y = 0.15 + 1.40X  P  Japan  r = 0.71*  Y = 25.25 - 0.04X  r = -0.05  Y = 6.76 + 0.47X  R  r = 0.41  Germany  Y = 4.95 + 1.42X  r = 0.81**  Y = 4.28 + 0.75X  S  Denmark  r = 0.90**  Y = 15.47 - 0.04X  r = -0.06  Y = 8.91 + 0.33X  U  Denmark  r = 0.52  Y = 9.00 + 0.61X  r = 0.46  Y = 8.79 - 0.01X  T  r = -0.02  Louisiana  Y = 13.73 + 0.57X  r = 0.77**  Y = 16.97 - 0.16X  V  r = -0.15  Louisiana  Y = 10.82 + 0.79X  r = 0.60  Y = 13.93 + 0.08X  w  r = 0.12  Louisiana  Y = 20.49 + 0.10X  r = 0.08  Y = 14.72 - 0.05X  X  r = -0.08  Louisiana  Y = 12.90 + 0.74X  r = 0.43  Y = 7.69 + 0.51X  Y  r = 0.43  Louisiana  Y = 20.46 + 0.38X  r = 0.21  Y = 16.56 + 0.05X  r = 0.07  equation  Leaf a r e a - X; P e t i o l e l e n g t h - Y; Sample s i z e - 10 o b s e r v a t i o n s p e r t r e a t m e n t r.05(8) = .6319* r.01(8) = .7646**  99 4.9.5  V a r i a t i o n i n L e a f Shape and  4.9.5.1  Markings  M a t e r i a l s and Methods  O b s e r v a t i o n o f l e a f shapes and markings o f J u l y 1977.  took p l a c e i n the l a t t e r p a r t  Leaves were c l a s s i f i e d a c c o r d i n g t o 4 shape c a t e g o r i e s ( O v a l ,  Round, Heart-shaped, Round i n c i s e d ) .  The i n v e r t e d "V" marks were grouped  p r e s e n t o r absent as used by Cahn and Harper  (1976).  The c l a s s i f i c a t i o n o f  the i n v e r t e d "V" mark was grouped i n t o t h r e e c a t e g o r i e s : complete and f a i n t , l a r g e and i n t e n s e .  b r o k e n and  faint,  The p r e s e n c e and absence o f antho-  c y a n i n f l e c k s were n o t e d as p e r Carnahan e t a l . (1955) and C o r k i l l 4.9.5.2  as  (1971).  O b s e r v a t i o n s and R e s u l t s  L e a f shape:-  O b s e r v a t i o n s on l e a f shape f o r the twenty  different  s t r a i n s i s g i v e n i n T a b l e 4.9:5.1:' E x a m i n a t i o n o f the d i s t r i b u t i o n suggests t h a t round l e a v e s and round i n c i s e d l e a v e s are the most abundant. I n v e r t e d "V" mark:-  The two methods used and d a t a assessment  o f the  s t u d i e s on the i n v e r t e d "V" mark are g i v e n i n T a b l e s 4.9.5.2 and 4.9.5.3. The F - t e s t i n the a n a l y s i s o f v a r i a t i o n suggests s i g n i f i c a n c e between s t r a i n but not among b l o c k means.  I n T a b l e 4.9.5.2 the r a t i o o f i n v e r t e d "V" marks  t o no "V" marks i s g i v e n ; the C r e s t o n and N e t h e r l a n d s s t r a i n s , had r a t i o s o f 3:1 o r 4:1 w i t h l e s s i n t e n s e marks, w h i l e the Japanese, German and L o u i s i a n a s t r a i n s had r a t i o s from 19:1. t o 20:0.  The two Denmark s t r a i n s a t r a t i o s o f  12:1 were i n t e r m e d i a t e . T a b l e 4.9.5.3 i s a c o n t i n g e n c y t a b l e d i s p l a y i n g markings  i n four categories.  Anthocyanin f l e c k i n g : -  The d i s t r i b u t i o n s are o b v i o u s l y not random. The r a t i o s f o r the p r e s e n c e and absence o f  a n t h o c y a n i n f l e c k i n g are g i v e n i n T a b l e 4.9.5.4.  There appears  be a d i f f e r e n c e between s t r a i n s , but i t i s not s t r o n g l y  to  indicated  leaf  T a b l e 4.9.5.1 C o n t i n g e n c y t a b l e and C h i - s q u a r e v a l u e s f o r w h i t e c l o v e r l e a f shapes on twenty s t r a i n s grown i n a u n i f o r m n u r s e r y a t U.B.C. Strain Shape  A  B  C  D  E  G  H  K  L  M  0  P  R  S  U  T  V  W  X  Y  Total  1  1  0  0  0  0  0  0  0  0  1  0  6  0  0  0  2  0  1  0  1  12  2  6  4  6  11  8  2  3  7  7  4  6  2  7  9  6  6  4  3  5  10  116  3  2  5  1  0  1  4  7  2  2  4  3  7  3  1  3  0  1  0  2  0  48  4  6  6  8  4  5  9  5  5  6  6  6  0  4  4  6  7  10  11  8  4  120  15  15  15  15  14  15  15  14  15  15  15  15  14  14  15  15  15  15  15  15  296  Total  Actual  2 X  = 136 .13  **  2 Expected x  .05(57)  L e a f Shape 1 = Oval  Ovate o r obovate  2 = Round  Orbiculate  3 = Heart shaped  Obcordate  4 = Round i n c i s e d  Orbiculate  notched  = 75..61  101 T a b l e 4.9.5.2 R a t i o o f water marks t o no water marks f o r twenty s t r a i n s o f w h i t e c l o v e r grown a t U.B.C. Strain  Origin  Water mark  No water mark  Pooled  A  Creston  15  5  B  Creston  18  2  C  Creston  16  4  D  Creston  12  3  E  Creston  16  3  G  Creston  16  4  H  Creston  14  6  K  Creston  17  3  L  Creston  13  7  M  Netherlands  18  2  0  Netherlands  12  8  P  Japan  20  0  20:0  R  Germany  19  1  19:1  S  Denmark  18  2  U  Denmark  14  6  T  Louisiana  19  1  V  Louisiana  20  0  W  Louisiana  20  0  X  Louisiana  20  0  Y  Louisiana  20  0  f- 4:1  3:1  12:1  h 19:1  T a b l e 4.9.5.3 Contingency t a b l e and C h i - s q u a r e v a l u e s f o r four c l a s s e s o f l e a f markings i n 20 s t r a i n s o f white c l o v e r grown i n a uniform n u r s e r y a t U.B.C. Total  No mark  5  2  4  3  5  6  3  5  7  4  9  2  3 20  8 20  4 20  5 15  A  B  C  3  4  6  3  7  2  8  0  1  2  6  1  0  0  0  0  57  Broken  and f a i n t  3  4  4  8 1 2  6  8  3  5  2  0  2  8  4  0  5  7  4  3  5  7  3  4  17 20 Ja P  12 20 Ge R  3 7 20 20 Denmark S U  15 20  0  0  0  1  2  0  62  Complete  and f a i n t  5  2  1  97  Large and intense Total  Actual x  2  D  = 156.64  5 0 19 20 Creston E G  4 20  4 20  5 20  H  K  L  Expected x  2  05(57)  =  6 6 20 20 Netherlands M 0  75.61  T  18 20  19 18 20 20 Louisiana V W X  19 20 Y  178 394  103 T a b l e 4.9.5.4 R a t i o o f a n t h o c y a n i n f l e c k i n g t o no f l e c k i n g f o r twenty s t r a i n s o f w h i t e c l o v e r grown a t U.B.C.  Strain  Origin  Flecking  No F l e c k i n g  Pooled  A  Creston  12  .8  B  Creston  4  16  C  Creston  6  14  D  Creston  4  11  E  Creston  7  12  G  Creston  6  14  H  Creston  9  11  K  Creston  9  11  L  Creston  6-  14  M  Netherlands  10  10  0  Netherlands  10  10  P  Japan  2  18  1:9.  R  Germany  8  12  2:3  S  Denmark  4  16  U  Denmark  7  13  T  Louisiana  5  15  V  Louisiana  5  15  W  Louisiana  4  16  X  Louisiana  12  Y  Louisiana  17  1:2  h 1:1  1:3  1:3  104 (Table 4.9.5.5).  The p r e s e n c e o r absence o f a n t h o c y a n i n  leaf flecks i s  o n l y a random a s s o c i a t i o n w i t h the presence o r absence o f the i n v e r t e d  "V"  l e a f mark (Table 4.9.5.6). 4.9.5.3  Discussion  L e a f shape was  not an easy parameter to study because o f the m u l t i -  p l i c i t y o f i n t e r m e d i a t e shapes.  However i t i s n o n e t h e l e s s  an  important  b i o l o g i c a l one s i n c e l e a v e s are the p r i m a r y organs o f p h o t o s y n t h e s i s . the o t h e r hand the i n v e r t e d "V" mark less s i g n i f i c a n t b i o l o g i c a l l y . "presence"  f l e c k i n g appear t o be  They a r e so d i f f i c u l t t o c l a s s i f y t h a t  o r "absence" were the o n l y r e l i a b l e c a t e g o r i e s .  t h e l e s s u s e f u l markings f o r f i e l d 4.9.6  and a n t h o c y a n i n  On  They are none-  identification.  V a r i a t i o n i n P l a n t Height  4.9.6.1  M a t e r i a l s and Methods  P l a n t h e i g h t was  measured i n l a t e September by p l a c i n g a r u l e r i n the  c e n t r e o f the p l a n t and n o t i n g the h e i g h t o f the canopy.  I n d i v i d u a l leaves  t h a t were h e l d h i g h e r than the canopy were i g n o r e d . 4.9.6.2  Observations  and  Results  P l a n t h e i g h t measurements a r e found i n T a b l e 4.9.6.1 and i n F i g u r e 4.9.6.1.  C r e s t o n s t r a i n s show  a wide range o f v a r i a t i o n , a l t h o u g h  L o u i s i a n a s t r a i n s were c o n s i s t e n t l y the t a l l e s t . o f v a r i a t i o n suggested significant.  The  the  F - t e s t s i n the a n a l y s i s  t h a t the d i f f e r e n c e between s t r a i n means were h i g h l y  P l a n t h e i g h t measurements f o l l o w c l o s e t o those o f p e t i o l e  length. 4.9.6.3  Discussion  Only one measurement o f p l a n t h e i g h t was  taken.  T h i s was  about  weeks p r i o r t o the p e t i o l e l e n g t h measurements but a g a i n the C r e s t o n  two strains  are i n t e r m e d i a t e w h i l e the L o u i s i a n a s t r a i n s a r e t a l l f o r t h i s time o f y e a r .  Table 4 . 9 . 5 . 5 C o n t i n g e n c y t a b l e and C h i - s q u a r e v a l u e s f o r a n t h o c y a n i n f l e c k i n g i n 20 s t r a i n s o f w h i t e c l o v e r grown i n a u n i f o r m n u r s e r y a t U.B.C. Strain A  B  C  D  4  6  E  G  H  K  L  M  O  P  R  S  U  T  V  W  .  4  7  5  5  4  X  Y  Total  Presence '  "  8  4  7  6  9  9  6  10  10  2  8  8  129  3  Absence  12  16  14  11  12  14  11  11  14  10  10  18;  12  16  13  15  15  16  12  17  265  Total  20  20  20  15  19  20  20  20  20  20  20  20  20  20  20  20  20  20  20  20  394  Actual x  2  = 23.41\  2 Expected x  05(19)"3°"14  /  o  106  T a b l e 4.9.5.6 Contingency t a b l e f o r w h i t e c l o v e r l e a f markings and a n t h o c y a n i n l e a f f l e c k i n g on twenty s t r a i n s grown i n a u n i f o r m n u r s e r y a t U.B.C.  Anthocyanin flecking  I n v e r t e d "V" L e a f Mark Absent Present  Total  Absent  36 (38.34)  229 (226.66)  265  Present  21 (18.66)  108 (110.34)  129  Total  57  337  394  Expected v a l u e s i n b r a c k e t s , Actual X  2  = 0.50  Expected X  2  .05(1) =3.84  107 T a b l e 4.9.6.1  P l a n t h e i g h t i n c e n t i m e t e r s f o r i n d i v i d u a l p l a n t s i n twenty s t r a i n s grown i n a u n i f o r m n u r s e r y a t U.B.C. No. p l a n t s Strain  Source  p e r samples  Mean  SD  CV%  Range  A  Creston  20  17.0  3.7  22  12-25  B  Creston  20  16.0  3.5  22  9-22  C  Creston  20  16.6  5.1  31  6-25  D  Creston  15  15.7  2.4  15  1 2 — 21  E  Creston  19  14.0  4.3  31  5-21  G  Creston  20  14.6  3.5  24  6-19  H  Creston  20  16.9  3.5  21  11 - 22  K  Creston  20  17.5  2.7  15  12 - 22  L  Creston  20  14.7  5.0  34  8-30  M  Netherlands  20  11.5  2.9  25  7-17  0  Netherlands  20  13.8  2.9  21  6-18  P  Japan  20  21.6  5.5  25  11-31  R  Germany  20  13.3  4.2  32  5-23  S  Denmark  20  13.2  3.2  .24  6-19  U  Denmark  20  12.9  3.8  29  4-18  T  Louisiana  20  22.9  2.6  11  19 - 28  V  Louisiana  20  23.8  4.1  17  14 - 30  W  Louisiana  20  22.7  4.4  19  9-29  X  Louisiana  20  21.4  5.3  25  7-29  Y  Louisiana  20  23.3  4.7  20  9-33  '  F i g u r e h.9.6.1  The v a r i a t i o n i n p l a n t h e i g h t f o r twenty s t r a i n s a t random i n each, o f f o u r b l o c k s ; each, s t r a i n r e p r e s e n t e d by f i v e plants:, i n ultimate p l o t s ; ultimate plots located a t random w i t h i n each, b l o c k , showing: a) b) c)  The a r i t h m e t i c mean f o r each, s t r a i n • The s i m p l e range by v e r t i c a l b a r ± one s t a n d a r d d e v i a t i o n from t h e mean by h o r i z o n t a l b a r s  30  25  2oy  15  10  H  K  M Neth.  Creston  STRAIN  P  R  i Ja.  Ger.  i  u  S Den  W Louis.  Y i  109 4.9.7  Variation i n  4.9.7.1  Cyanogenesis  M a t e r i a l s and Methods  In the l a t t e r h a l f o f September, a l l p l a n t s were sampled f o r cyanogenesis.  The method used was by means o f the p i c r a t e paper t e s t , u s i n g a  set of standards. MacVicar  P i c r a t e paper was p r e p a r e d as o u t l i n e d by Nowosad and  (1940) and s t o r e d i n an a i r t i g h t c o n t a i n e r .  s o l u t i o n was p r e p a r e d by d i s s o l v i n g 241 l i t r e o f d i s t i l l e d water.  mg'  A standard cyanide  o f p o t a s s i u m c y a n i d e i n one  At 09:00 h o u r s , samples o f about 150 mg of.... '  f r e s h p l a n t t i s s u e from each p l a n t were p l a c e d i n 10 mm  x 120 mm.test t u b e s ,  samples were b r u i s e d and 10 drops o f c h l o r o f o r m added.  A s t r i p of picrate  paper was p l a c e d i n the tube and h e l d i n p l a c e by a r u b b e r s t o p p e r .  A set  o f s t a n d a r d s were made up by p l a c i n g a range o f measured q u a n t i t i e s o f the c y a n i d e s o l u t i o n i n t e s t tubes t o g i v e a range o f v a l u e s from 0 ug t o 80 Pg-  .  A s t r i p o f p i c r a t e paper was p l a c e d i n each o f t h e s e tubes and h e l d  i n p l a c e w i t h a rubber stopper. twenty h o u r s .  A l l samples were i n c u b a t e d a t 30°C f o r  P i c r a t e papers were then compared w i t h the s t a n d a r d s and a  r e l a t i v e r a t i n g o f the l e v e l o f r e a c t i o n f o r each p l a n t was 4.9.7.2  established.  O b s e r v a t i o n s and R e s u l t s  There were some v a r i a t i o n s i n HCN  l e v e l s from b l o c k t o b l o c k because  o n l y one b l o c k c o u l d be done on a g i v e n day. s t r a i n s were v e r y marked.  The d i f f e r e n c e s between  A l l C r e s t o n and N e t h e r l a n d s s t r a i n s gave a  n e g a t i v e r e a c t i o n w h i l e a l l L o u i s i a n a s t r a i n s gave a h i g h l y p o s i t i v e r e a c t i o n . The Japanese s t r a i n Tohoku was n e g a t i v e w h i l e one Danish s t r a i n P a j b e r g M i l k a and a German s t r a i n K i v i gave o c c a s i o n a l p o s i t i v e 4.9.7.3  reactions.  Discussion  The method o f making a s e t o f s t a n d a r d s gave a r e a s o n a b l e a p p r o x i m a t i o n o f the amount o f r e l e a s e by each p l a n t o f hydrogen c y a n i d e .  F o r the  purpose  110 of  t h i s s t u d y , p o s i t i v e o r n e g a t i v e r e a c t i o n s were s u f f i c i e n t .  4.9.8  V a r i a t i o n i n P l a n t Weight  4.9.8.1  M a t e r i a l s and Methods  On two d a t e s , August was  1 8 t h and October 19th, growth was c u t ; t h e m a t e r i a l  thoroughly d r i e d i n a pot hole d r i e r .  Weights were r e c o r d e d i n gms o f  air-dry material. 4.9.8.2  O b s e r v a t i o n s and R e s u l t s  The d a t a o b t a i n e d from t h e s a m p l i n g on t h e two dates a r e g i v e n i n Tables 4.9.8.1 and 4.9.8.2 and F i g u r e s 4.9.8.1 and 4.9.8,2.  The F - t e s t was  i n s i g n i f i c a n t f o r weight between s t r a i n s f o r t h e f i r s t date (August 18th) and t h i s i s i l l u s t r a t e d i n F i g u r e 4.9.8.1.  The second date (October 19th)  shows t h e lower w e i g h t s f o r a l l s t r a i n s b u t i t i s noteworthy t h a t t h e L o u i s i a n a s t r a i n s a r e h e a v i e r p r o d u c e r s i n l a t e summer and f a l l than t h e C r e s t o n s t r a i n s ; l e a f a r e a responds l i k e w i s e . 4.9.8.3 D i s c u s s i o n There appears t o be a r e l a t i o n s h i p between l e a f a r e a and p l a n t w e i g h t , however, i t i s noteworthy t h a t s m a l l e r l e a v e d p l a n t s a r e more p e r s i s t e n t . 4.10  V a r i a t i o n W i t h i n and Between Clones  4.10.1  Comment on T r i a l  Layout  On t h e 1 s t September 1976 p l a n t s were c o l l e c t e d from f o u r areas i n each o f f i v e f i e l d s i n t h e C r e s t o n a r e a .  The p l a n t s o r i g i n a t e d from p l a n t -  i n g s made i n 1975 and 1976 and a r e d e s i g n a t e d by t h e name o f t h e farmer owning a f i e l d , and by y e a r o f p l a n t i n g .  These p l a n t s were grown i n t h e  greenhouse a t U.B.C. and i n December 1976 c u t t i n g s were made from plants.  individual  Three c u t t i n g s from a s i n g l e r u n n e r made up a s e t o f t h r e e genet-  i c a l l y "identical" plants.  Each s e t was n o t n e c e s s a r i l y r e l a t e d t o t h e  111 T a b l e 4.9.8.1 I n d i v i d u a l p l a n t w e i g h t s i n grams f o r twenty s t r a i n s grown i n a u n i f o r m n u r s e r y a t U.B.C. Strain  Source  No-. •• p l a n t s ' p e r sample,,;  Sampling d a t e 18-8-77(1)  Mean  SD  CV%  Range  A  Creston  20  409  115  28  282 - 772  B.  Creston  20  492  146  30  270 - 961  C  Creston  20  419  81  19  282 - 664  D  Creston  15  421  79  19  289 - 567  E  Creston  19/  405  89  22  255 - 559  G  Creston  20  435  120  28  300 - 748  H  Creston  20  476  132  28  313 - 838  K  Creston  20  406  81  20  280 - 574  L  Creston  20  384  91  24  223 - 548  M  Netherlands  20  478  140  29  257 - 817  0  Netherlands  20  392  91  23  241  P  Japan  20  424  140  33  235 - 803  R  Germany  20  328  126  38  158 - 622  S  Denmark  20  430  128  30  259 - 819  U  Denmark  20  379  120  32  181 - 622  T  Louisiana  20  374  126  34  183 - 630  V  Louisiana  20  434  131  30  260 - 666  W  Louisiana  20  376  95  25  271  X  Louisiana  20  445  173  39  241 - 975  Y  Louisiana  20  409  110  27 ; • 273 - 684  - 577  - 584  F i g u r e 4.9.8.1  The v a r i a t i o n i n s t a n d i n g c r o p w e i g h t from t h e h a r v e s t on t h e 18-8-77 ( l ) o f w h i t e c l o v e r p l a n t s from t h e twentys t r a i n s a t random i n each o f f o u r b l o c k s each s t r a i n r e p r e s e n t e d hy f i v e p l a n t s in ultimate p l o t s ; ultimate plots l o c a t e d a t random w i t h i n each b l o c k , showing: a) b) c)  The a r i t h m e t i c mean f o r each s t r a i n The s i m p l e range by v e r t i c a l b a r - one s t a n d a r d d e v i a t i o n from t h e mean by h o r i z o n t a l b a r s  1000.  U a C . plot: weight 0)  900  800  700\  600h  E  O)  •-  500r  400-  300-  200150-  L_  A  B  C  D  E  G  H  K  L  M  O Neth.  Creston STRAIN  P i  R  i J a . Ger.  S Den.  T i  V  W Louis.  X  Y  113 Table  4.9.8.2  I n d i v i d u a l p l a n t w e i g h t s i n grams f o r twenty s t r a i n s grown i n a u n i f o r m nurs e r y a t U.B.C.  Sampling  date 19-10-77(2)  Source  No. p l a n t s per sample '  Mean  SD  CV%  A  Creston  10  30  25  83  14 -  93  B  Creston  10  31  18  58  8 -  52  C  Creston  10  34  19  56  6 -  72  D  Creston  5  37  20  54  21 -  71  E  Creston  ,9  19  19  100  5 -  64  G  Creston  10  41  33  80  H  Creston  10  46  22  48  23 -  77  K  Creston  19  40  21  53  9 -  68  L  Creston  1.0  25  18  72  4 -  72  M  Netherlands  10  35  22  63  7 -  82  0  Netherlands  10  40  28  70  3 -  73  P  Japan  10  85  30  35  R  Germany  :.9  50  22  44  9 -  79  S  Denmark  19  32  20  63  6 -  64  U  Denmark  10  4:3  29  "67- --  34 -  86  T  Louisiana;.  10  105  43  41  66 - 206  'V.  Louisiana  10  96  40  42  25 - 125  W  Louisiana  10  85  47  55  10 - 186  X  Louisiana  10  91  22  24  67 - 126  Y  Louisiana  10  113  19  17  75 - 135  Strain  Range  6 - 108  37 - 148  Figure  4.9.8.2  The v a r i a t i o n i n s t a n d i n g c r o p weight from h a r v e s t on t h e 19-10-77 (2) o f w h i t e c l o v e r p l a n t s from twenty s t r a i n s a t random i n each o f f o u r b l o c k s ; each s t r a i n r e p r e s e n t e d by f i v e p l a n t s i n ultimate p l o t s ; ultimate plots located a t random w i t h i n each b l o c k , showing: a) b) c)  The a r i t h m e t i c mean f o r each s t r a i n The s i m p l e range by v e r t i c a l b a r ± one s t a n d a r d d e v i a t i o n from t h e mean by h o r i z o n t a l b a r s  220r  U.B.C. plot: weight (2) 200^  180r  160h  140  r  120  O)  1001  801  60  40  20)-  H  L  Creston  M Neth.  STRAIN  O  P i Ja.  R  Ger.  s  u  I  I  Den.  T  V  W Louis.  X  115 o t h e r s e t s from t h e same a r e a o f t h e f i e l d .  The c u t t i n g s were p l a n t e d i n  u n s t e r i l i z e d C r e s t o n s o i l and p l a c e d i n t h e m i s t i n g chamber.  On A p r i l 1 s t ,  1977, these p l a n t s were moved t o t h e c o l d frames f o r h a r d e n i n g .  On June  14th t h e p l a n t s were s e t out i n Totem F i e l d , U.B.C. i n a randomized  design  with four blocks. The main r e a s o n f o r t h e c l o n a l p r o p a g a t i o n was t o o b t a i n p l a n t s t h a t were g e n e t i c a l l y i d e n t i c a l so t h a t we c o u l d compare t h e v a r i a t i o n caused by n o n - g e n e t i c f a c t o r s such as v a r i a t i o n i n s o i l , r o o t damage and o t h e r unidentifiable 4.10.2  factors.  V a r i a t i o n i n Leaf Area  4.10.2.1  M a t e r i a l s and Methods  Two samples were t a k e n from each p l a n t on each o f two dates and October 2 0 t h ) .  ( J u l y 20th  A sample c o n s i s t e d o f a t r i f o l i a t e l e a f and i t s p e t i o l e .  One sample was t a k e n from t h e t h i r d open l e a f from t h e end o f a s t o l o n (young l e a f ) .  The o t h e r sample was t a k e n from t h e c e n t r e o f t h e p l a n t .  Leaf a r e a was e s t i m a t e d i n square c e n t i m e t e r s by use o f the.method o u t l i n e d by W i l l i a m s e t a l . (1964). 4.10.2.0  O b s e r v a t i o n s and R e s u l t s  The r e s u l t s -of these o b s e r v a t i o n s a r e l i s t e d i n T a b l e s 4.10.2.1 and 4.10.2.2. and F i g u r e s 4.10.2.1 and 4.10.2.2.  Considerable modification i n  l e a f a r e a i s e v i d e n t from t h e l a t e p l a n t i n g .  The F - t e s t i n t h e a n a l y s i s o f  v a r i a t i o n suggested d i f f e r e n c e s between s t r a i n s and between t h e two s a m p l i n g d a t e s ; p l a n t s o f t h e 1976 p l a n t i n g showed a s m a l l r e d u c t i o n i n mean l e a f area. T a b l e s 4.10.2.3 and 4.10.2.4 show t h e v a r i a b i l i t y w i t h i n each c l o n e . T h i s v a r i a b i l i t y i s a s s o c i a t e d m a i n l y w i t h e r r o r i n s a m p l i n g and o t h e r noninherited factors.  I f we compare t h e average c o e f f i c i e n t s o f v a r i a t i o n t o  116  Table 4.10.2.1 Area representation of individual leaves (in square centimeters) for five strains of white clover grown in a uniform nursery at U.B.C, sampled 20-7-77(1). ~ain  Source  2 Mean(cm )  ' SD(cm ) 2  cn  Rahjge  1  Staples 1975  7.68  1.65  21  4  - 12.6  2  Ogilvie 1975  7.88  2.45  31  5  - 15.8  3  Mulligan 1976  5.79  1.51  26  3.2 - 10  4  Eastman 1975  7.14  2.85  40  2  5  Eastman 1976  6.94  2.65  38  3.2 - 15.8  - 12.6  Number of leaves for each treatment - 48  Table 4.10.2.2 Area representation of individual leaves (in square centimeters) for five strains of white clover grown i n a uniform nursery at U.B.C., sampled 20-10-77(2). Strain  Source  2 Mean(cm )  SD(cm ) 2  cv%  Range  1  Staples 1975  7.10  2.13  30  2.5 - 12 .6  2  Ogilvie 1975  7.30  4.10  55  1.6 - 20  3  Mulligan 1976  6.81  2.6  38  2.5 - 12 .6  4  Eastman 1975  6.59  2.8  42  2  5  Eastman 1976  5.01  1.62  32  1.3 - 10  Number of leaves for each treatment - 48  - 12 .6  Figure  4.10.2.1  The v a r i a t i o n i n l e a f a r e a on t h e 20-7-77 ( l ) ; p l a n t s were grown from c u t t i n g s and e s t a b l i s h e d i n a u n i f o r m n u r s e r y . The f i v e s t r a i n s a r e a t random i n each o f f o u r b l o c k s ; each s t r a i n i s r e p r e s e n t e d by n i n e p l a n t s i n t h e u l t i m a t e p l o t s ; the u l t i m a t e p l o t s are l o c a t e d a t random w i t h i n each b l o c k , showing: a) b) c)  The a r i t h m e t i c mean f o r each s t r a i n • The s i m p l e range by v e r t i c a l b a r t o n e s t a n d a r d d e v i a t i o n from t h e mean by h o r i z o n t a l b a r s  117  U.B.C. Clones: Leaf Area 0)  E  8  20  15  lOf-  +  3 STRAIN  I*.  Figure  4.10.2.2.  The v a r i a t i o n i n l e a f a r e a on t h e 20-10-77 ( 2 ) ; p l a n t s were grown from c u t t i n g s and e s t a b l i s h e d i n a uniform nursery. The f i v e s t r a i n s a r e a t random i n each o f f o u r b l o c k s ; each s t r a i n i s r e p r e s e n t e d by n i n e p l a n t s i n t h e u l t i m a t e p l o t s ; the u l t i m a t e p l o t s are l o c a t e d a t random w i t h each b l o c k . a) b) c)  The a r i t h m e t i c mean f o r each s t r a i n • The s i m p l e range by v e r t i c a l b a r ± one s t a n d a r d d e v i a t i o n from t h e mean by h o r i z o n t a l b a r s  U.B.C.  Clones:  Leaf A r e a  (2)  20r  15  10  oL  1  3 STRAIN  119  Table 4.10.2.5 Mean l e a f area v a r i a b i l i t y w i t h i n clones of f i v e s t r a i n s o f white c l o v e r grown i n a uniform nursery a t U . B . C ; three p l a n t s i n each clone, eight clones i n each s t r a i n ; average of the mean and the standard d e v i a t i o n c o e f f i c i e n t f o r eight clones i n each s t r a i n ; c o l l e c t i o n date 20-7-77. a - old leaf b - young l e a f Strain  Source  Mean  SD  CV%  1  Staples 1975  a - 7.86 b - 7.49  1.06 1.48  13 20  2  O g i l v i e 1975  a - 8.06 b -7.69  1.46 1.75  18 23  3.  M u l l i g a n 1976  a - 5.74 b - 5.84  0.78 1.56  14 27  4  Eastman 1975  a - 8.10. b - 6.27  2.19 1.21  27 19  5  Eastman 1976  a - 6.31 b -7.57  1.23 1.32  19 17  120  Table 4.10.2.4 Mean leaf area variability within clones of five strains of white clover grown i n a uniform nursery at U.B.C; three plants i n each clone, eight clones i n each strain; average of the mean and the standard deviation for eight clones i n each strain; collection date 20-10-77. a - old leaf b - young leaf Strain  Source  Mean  SD  CV!  1  Staples 1975  a - 6.88 b - 7.33  1.33 1.34  19 18  2 •  Ogilvie 1975  a - 6.41 b - 8.20  1.65 1.96  26 24  3  Mulligan 1976  a - 6.02 b - 7.59  1.01 1.16  17 15  4  Eastman 1975  a - 6.50 b - 6.86  1.34 1.29  21 19  5  Eastman 1976  a - 5.05 b - 4.98  1.02 1.68  20 34  121 to t h o s e i n T a b l e s 4.10.2.1, 4.10.2.2, 4.9.3.1 and  4.9.3.2 we  about 30-60 p e r c e n t v a r i a t i o n can be a t t r i b u t e d t o g e n e t i c 4.10.3  that  factors.  V a r i a t i o n i n P e t i o l e Length  4.10.3.1  Materials  The  and  Methods  same samples t a k e n f o r l e a f a r e a a l s o s e r v e d f o r p e t i o l e  measurements.  leaf  4.10.3.2  p e t i o l e t o the  base  junction  pedicels.  O b s e r v a t i o n s and  The  length  P e t i o l e l e n g t h s were measured i n c e n t i m e t e r s from the  o f the p e t i o l e a t the j u n c t i o n o f the s t i p u l e s and o f the  see  Results  r e s u l t s o f o b s e r v a t i o n s on p e t i o l e l e n g t h are g i v e n i n T a b l e s  4.10.3.1 and 4.10.3.2.  The  F - t e s t i n the a n a l y s i s  of v a r i a t i o n suggests a  d i f f e r e n c e between s t r a i n s b o t h f o r young p e t i o l e s and b o t h dates o f o b s e r v a t i o n ( J u l y 20th and  old petioles  on  October 20th) .  T a b l e 4.10.3.3, the r e l a t i o n s h i p o f l e a f a r e a to p e t i o l e l e n g t h f o r two  sampling dates. S t r a i n 4 i s the o n l y s t r a i n showing a h i g h l y  the  significant  r e l a t i o n s h i p of l e a f area to p e t i o l e length f o r both dates. 4.10.4  Variation i n Plant  4.10.4.1  Materials  and  Weight  Methods  On September 1st a l l p l a n t s d r i e r , and 4.10.4.2 The strains.  were h a r v e s t e d , d r i e d i n the pot  hole  weighed. O b s e r v a t i o n s and  Results  F - t e s t i n the a n a l y s i s of v a r i a t i o n suggests d i f f e r e n c e s The  4.10.4.1 and  a i r - d r y weights of material F i g u r e 4.10.4.1.  between  h a r v e s t e d are p r e s e n t e d i n T a b l e  S t r a i n t h r e e o n l y shows any  abnormal y i e l d .  T a b l e 4.10.4.2 g i v e s the average v a r i a t i o n t h a t e x i s t s between p l a n t s a c l o n e f o r the  f i v e s t r a i n s and  those i n T a b l e s 4.10.4.1 and i n p l a n t w e i g h t i s due  comparing the c o e f f i c i e n t s o f v a r i a t i o n  4.9.8.1 we  to genetic  within  see  factors.  that  to  75 t o 30 p e r c e n t v a r i a t i o n  122  T a b l e 4.10.3.1 P e t i o l e length i n centimeters f o r f i v e s t r a i n s o f white c l o v e r grown i n a u n i f o r m n u r s e r y a t U.B.C, sampled 20-7-77. Strain  Source  Mean  S.D.  CV %  Range  1  S t a p l e s 1975  13.71  3.68  27  7-21  2  O g i l v i e 1975  12.98  4.26  33  6-21  3  M u l l i g a n 1976  8.94  2.49  28  5-15  4  Eastman 1975  13.48  3.93  29  6 - 22  5  Eastman 1976  11.42  3.44  30  6-20  Number o f samples f o r each treatment - 48.  T a b l e 4.10.3.2 P e t i o l e length i n centimeters f o r f i v e s t r a i n s o f white clover grown i n a u n i f o r m n u r s e r y a t U.B.C, sampled 20-10-77. Strain  Source  Mean  S,,D.  CV %  Range  1  S t a p l e s 1975  15.58  3,.49  22  8-23  2  O g i l v i e 1975  14.42  5,.13  36  6-25  3  M u l l i g a n 1976  13.31  3..63  27  6-19  4  Eastman 1975  13.42  4..88  36  5-22  5  Eastman 1976  11.54  3..46  30  4-18  Number o f samples f o r each treatment - 48.  Table 4.10.3.3 L i n e a r r e g r e s s i o n e q u a t i o n s and c o r r e l a t i o n c o e f f i c i e n t s f o r w h i t e c l o v e r c l o n a l m a t e r i a l f o r two dates grown i n a u n i f o r m n u r s e r y a t U.B.C.  P l a n t s were v e g e t a t i v e l y p r o p a g a t e d from m a t e r i a l o f C r e s t o n o r i g  F i v e t r e a t m e n t s , each t r e a t m e n t c o n t a i n e d e i g h t groups w i t h t h r e e g e n e t i c a l l y i d e n t i c a l p l a n t s i n each group.  Treatment No.  Name  L e a f a r e a and p e t i o l e l e n g t h (Date 20-7-77)  L e a f a r e a and p e t i o l e l e n g t h (Date 20-10-77)  Regression Equation  Regression Equation  Correlation Coefficient  Correlation Coefficient  1  Staples  1975  Y= 6.38+0.98X  r=0.43  Y=13.37+0.21X  r=0.13  2  O g i l v i e 1975  Y= 8.73+0.53X  r=0.34  Y= 8.46+0.82X  r=0.65  3  M u l l i g a n 1976  Y= 8.03+0.22X  r=0.12  Y=13.78-0.001X  4  Eastman 1975  Y= 6.64+0.96X  r=0.69  Y= 4.88+1.28X  r=0.0007 ftft r=0.74  Eastman 1976  Y=11.24+0.02X  r=0.02  Y=11.90-0.07X  r=-0.03  r.  L e a f a r e a - X; P e t i o l e L e n g t h - Y:  L e a f a r e a - X; P e t i o l e Length - Y  Sample s i z e - 24 o b s e r v a t i o n s p e r t r e a t m e n t , r.05(22) = 0.4143* r.01(22) = 0.5268**  **  124 Table 4 . 1 0 . 4 . 1 Top weight i n grams f o r  f i v e s t r a i n s o f white clover  grown i n a u n i f o r m n u r s e r y a t U..B.C. Strain  Source  Mean  SD  CV %  1  S t a p l e s 1975  139.6  48.3  35  71.3-244 .8  2  O g i l v i e 1975  146.7  37.8  26  81.0-218..7  3  M u l l i g a n 1976  90.6  17.7  20  60.2-133..3  4  Eastman 1975  129.1  50.3  39  75.3-260.,7  5  Eastman 1976  123.2  30.3  25  80.8-186. 0  Range  Number o f samples f o r each t r e a t m e n t - 24.  Table 4 . 1 0 . 5 . 1 Height i n centimeters f o r f i v e s t r a i n s o f white  clover  grown i n a u n i f o r m n u r s e r y a t U.B.C. Strain  Source  Mean  SD  1  S t a p l e s 1975  17.4  2  O g i l v i e 1975  3  CV %  Range  2.8  16  7- 22  18.7  6.2  33  9-29  M u l l i g a n 1976  15.4  2.9  19  9-19  4  Eastman 1975  15.5  4.9  32  6-23  5  Eastman 1976  14.9  3.2  22  8- 20  Number o f samples f o r each treatment - 24.  Figure 4.10.4.1  The v a r i a t i o n i n top weight f o r p l a n t s grown from cuttings i n a uniform nursery; the f i v e s t r a i n s at random i n each of four blocks; each s t r a i n represented by nine plants i n ultimate p l o t s ; u l timate p l o t s located at random w i t h i n each b l o c k , showing: a) b) c)  The arithmetic mean f o r each s t r a i n • The simple range by v e r t i c a l bar ± one standard deviation from the mean by h o r i z o n t a l bars  I2S ir.  U.B.C. Clones: Top weight  £ CD  280  220  160  k  100  0»-  I  3 STRAIN  5  126  T a b l e 4.10.4.2 Mean, w e i g h t and s t a n d a r d d e v i a t i o n o f t o p growth w i t h i n c l o n e s from f i v e s t r a i n s o f w h i t e c l o v e r grown i n a u n i f o r m n u r s e r y a t U.B.C; t h r e e p l a n t s i n each c l o n e , e i g h t c l o n e s i n each s t r a i n . Strain  Source  Mean  S.D.  CV  1  S t a p l e s 1975  139.63  15.91  11  2  O g i l v i e 1975  146.67  10.13  7  3  M u l l i g a n 1976  90.62  14.40  16  4  Eastman 1975  129.11  14.29  11  5  Eastman 1976  123.19  14.65  12  Table  4.10.5.2  Mean, p l a n t h e i g h t and s t a n d a r d d e v i a t i o n w i t h i n c l o n e s from f i v e s t r a i n s o f w h i t e c l o v e r grown i n a u n i f o r m n u r s e r y a t U.B.C: t h r e e p l a n t s i n each c l o n e , e i g h t c l o n e s i n each Strain  Source  Mean  S.D.  CV %  1  S t a p l e s 1975  17.42  1.75  10  2  O g i l v i e 1975  18.67  2.24  12  3  M u l l i g a n 1976  15.38  1.31  9  4  Eastman 1975  15.54  1.48  10  5  Eastman 1976  14.92  1.80  12  strain.  127  4.10.5 4.10.5.1  V a r i a t i o n i n p l a n t height M a t e r i a l s and methods  P l a n t h e i g h t was made i n c e n t i m e t e r s  measured i n e a r l y September.  The measurement  was  by measuring the d i s t a n c e from the ground t o the upper  s u r f a c e of the p l a n t canopy.  S i n g l e l e a v e s above the canopy l e v e l were  ignored. 4.10.5.2 The strains.  Observations  and  results  F t e s t i n the a n a l y s i s o f v a r i a t i o n suggests The  r e s u l t s are p r e s e n t e d  d i f f e r e n c e s between  i n T a b l e 4.10.5.1 and  F i g u r e 4.10.5.1.  Table 4.10.5.2 g i v e s average v a r i a t i o n t h a t e x i s t s between p l a n t s w i t h i n a c l o n e f o r the 5 s t r a i n s .  By comparing the c o e f f c i e n t o f v a r i a t i o n i n  Tables 4.9.6.1, 4.10.5.1 to 4.10.5.2 we  observe t h a t 54 p e r c e n t  v a r i a t i o n i n p l a n t h e i g h t i s a t t r i b u t e d to g e n e t i c  factors.  of  the  Figure k.10.5.1  The v a r i a t i o n i n height of white clover plants grown from cuttings i n a uniform nursery; the f i v e s t r a i n s at random i n each of four blocks; each s t r a i n represented by nine plants i n ultimate p l o t s ; ultimate p l o t s located at random w i t h i n each block, showing: a) The arithmetic mean f o r each s t r a i n i b) The simple range by v e r t i c a l bar c) one standard d e v i a t i o n from the mean by h o r i z o n t a l bars  U.B.C. Clones: Plant Height  0-~ 3 STRAIN  129 4.10.6  Variation  4.10.6.1  i n L e a f Markings  M a t e r i a l s and Methods  The l e a f markings observed were the i n v e r t e d "V" marks and t h e anthoc y a n i n f l e c k i n g marks.  The g r o u p i n g o f t h e i n v e r t e d "V" l e a f mark and t h a t  f o r f l e c k i n g was by means o f t h e s i m p l e o b s e r v a t i o n o f p r e s e n c e and 4.10.6.2  absence.  O b s e r v a t i o n s and R e s u l t s  R e s u l t s o f counts o f t h e i n v e r t e d "V" mark and a n t h o c y a n i n f l e c k s  are  found i n T a b l e 4.10.6.1, the presence o f the l e a f mark g e n e r a l l y b e i n g the one i n g r e a t e r abundance. than p r e s e n t .  A n t h o c y a n i n f l e c k s were more f r e q u e n t l y absent  I t was n o t e d i n the f i e l d t h a t a l l p l a n t s from each c l o n e had  s i m i l a r i n v e r t e d "V" l e a f marks and l e a f f l e c k s .  A l t h o u g h p l a n t s were c o l -  l e c t e d a t random, i t i s i n t e r e s t i n g t o n o t e t h e d i f f e r e n c e i n r a t i o s o f l e a f marks t o no l e a f marks i n each s t r a i n .  T a b l e 4.10.6.2 g i v e s the con-  t i n g e n c y t a b l e f o r t h e p r e s e n c e and absence o f the two s e t s o f l e a f m a r k i n g s . 4.11  Coated C l o v e r Seed T r i a l  4.11.1  M a t e r i a l s and Methods  The t r i a l was u n d e r t a k e n on the Totem F i e l d a t U.B.C. was o f C r e s t o n o r i g i n and the c o a t i n g p r o c e s s was I n c . , Manteca, C a l i f o r n i a .  The seed used  done by C e l P r i l  On June 23rd, t h e t r i a l was  Industries  l a i d out and  on a t h r e e by t h r e e L a t i n square d e s i g n , each p l o t b e i n g t h r e e meters t h r e e meters.  Treatments were a) c o a t e d seed, b) s t a n d a r d  seeded by  inoculation,  c) not i n o c u l a t e d . 4.11.2  O b s e r v a t i o n s and R e s u l t s  On September 23rd one meter square q u a d r a t s were c l i p p e d from each p l o t , a i r - d r i e d i n the p o t h o l e d r i e r and weighed t o t h e n e a r e s t ounce. No s i g n i f i c a n t d i f f e r e n c e was o b s e r v e d between any o f the t r e a t m e n t s .  130 T a b l e 4.10.6.1 Counts o f l e a f marks f o r f i v e s t r a i n s o f w h i t e c l o v e r grown as c l o n a l m a t e r i a l i n a u n i f o r m n u r s e r y a t U.B.C. P l a n t s were v e g e t a t i v e l y propagated from m a t e r i a l o f C r e s t o n o r i g i n . F i v e t r e a t m e n t s , each t r e a t m e n t c o n t a i n e d e i g h t groups w i t h t h r e e g e n e t i c a l l y i d e n t i c a l p l a n t s i n each group. Plants with inverted L e a f mark Present  Plants with inverted L e a f mark Absent  1  9 (6)  15 (18)  2  12 (0)  12 (24)  3  24 (0)  0 (24)  4  15 (6)  9 (18)  5  18 (9)  12 (21)  Strain  P l a n t s o u t s i d e o f b r a c k e t s - i n v e r t e d "V" mark. Plants i n s i d e o f brackets  - anthocyanin f l e c k s .  Table 4.10.6.2 Contingency t a b l e f o r i n v e r t e d l e a f marks and a n t h o c y a n i n f l e c k i n g on c l o n a l m a t e r i a l grown i n a u n i f o r m n u r s e r y a t U.B.C. P l a n t s were v e g e t a t i v e l y p r o p a g a t e d from m a t e r i a l o f C r e s t o n o r i g i n . Five t r e a t ments, each t r e a t m e n t c o n t a i n e d e i g h t groups w i t h t h r e e g e n e t i c a l l y i d e n t i c a l p l a n t s i n each group.  Anthocyanin leaf flecks Absent  I n v e r t e d "V" L e a f Marks Ab s ent Present  Total  39 (40)  66 (65)  105  Present  9 (8)  12 (13)  21  Total  48  78  126  2 X a c t u a l =0.26  X  e x p e c t e d .05(1) :  131 4.11.3 The  Discussion c o a t i n g o f w h i t e c l o v e r seed under U.B.C. f i e l d c o n d i t i o n s d i d not  g i v e any a p p r e c i a b l e i n c r e a s e s i n e s t a b l i s h m e n t seed, dusted 4.12  o r not dusted w i t h humus base r h i z o b i a l  Acetylene Reduction  4.12.1  o r y i e l d t o t h a t o f uncoated culture.  Trials  M a t e r i a l s and Methods  An e t h y l e n e a n a l y z e r  ( p o r t a b l e gas chromatograph) was  the Department o f P l a n t S c i e n c e at U.B.C.  constructed i n  S p e c i f i c a t i o n s and d e s i g n were  f o l l o w e d c l o s e l y t o those o u t l i n e d by M a l l a r d et a l . (1977).  Gas  chrom-  a t o g r a p h i c and t r o u b l e s h o o t i n g p r o c e d u r e s were c o n s u l t e d from the t e x t by McNair and B o n e l l i obtained  80-100) was 758,  The  ordered  mm  T GS-812  Corp., 219 West Rhapsody,  column packed w i t h Poropak R and  The  l e n g t h and d i a m e t e r o f the column  ( M a l l a r d et a l . 1977).  p r o v i d e d by a 1 2 - v o l t c a r b a t t e r y .  E l e c t r i c a l power f o r the The  was San  Poropak N (mesh s i z e  prepacked from Chromatographic S p e c i a l i s t s L t d . ,  B r o c k v i l l e , Ontario.  44 cm x 3.18 was  The T a g u c h i gas sensor model No.  from Southwest T e c h n i c a l P r o d u c t s  A n t o n i o , Texas.  Box  (1969).  c a r r i e r gas was  P.O. was  analyzer  n i t r o g e n at  20  found t h a t good s e p a r a t i o n o f e t h y l e n e from a c e t y l e n e c o u l d  be  ml/min. 4.12.2  Observations  I t was  and  Results  o b t a i n e d from a c a r r i e r gas f l o w r a t e o f 20 ml per minute. o f the a c e t y l e n e peak proved p r o b l e m a t i c .  The  However t a i l i n g  c a r r i e r gas was  t h e n changed  t o compressed a i r and good s e p a r a t i o n o f e t h y l e n e from a c e t y l e n e was w i t h no t a i l i n g o f the a c e t y l e n e peak.  S e n s i t i v i t y appeared good, w i t h 1  p a r t per m i l l i o n b e i n g d e t e c t e d when a sample o f 1 ml was 0.1  ml was  conditions.  obtained  introduced.  When  i n j e c t e d , 10 p a r t s per m i l l i o n were d e t e c t e d under l a b o r a t o r y  132 The column i s unheated and r e l i e s on t h e ambient a i r temperature. However m o i s t u r e c o u l d become p r o b l e m a t i c i f samples a r e r e n d e r i n g t h e column 14.12.3  contaminated,  ineffective.  Discussion  I t i s considered that the u n i t i s s u f f i c i e n t l y accurate t o detect n i t r o g e n a s e a c t i v i t y as e a r l y as one hour a f t e r t h e b e g i n n i n g o f i n c u b a t i o n o f samples i n s i t u i n s o i l .  133 5.  GENERAL DISCUSSION AND The  CONCLUSIONS  i n f o r m a t i o n p r o v i d e d i n T a b l e 1.1  shows t h a t the p r e s e n t  hectarage  i n w h i t e c l o v e r t h a t i s grown i n the C r e s t o n V a l l e y o f B r i t i s h Columbia i s a q u a r t e r o f t h a t o f a decade ago.  L i k e w i s e , t h e y i e l d o f seed p e r h e c t a r e  d e c l i n e d , w h i l e the p r i c e o f common w h i t e c l o v e r seed has doubled time.  has  i n the same  The g e n e r a l t r e n d f o r some markets o f w h i t e c l o v e r seed, e s p e c i a l l y i n  the European s e c t i o n , i s t o c l o s e t h e i r doors on common seed and open them more a v i d l y to c e r t i f i e d seed.  The r e t u r n s t o growers f o r p r o d u c i n g  certified  seed a r e l u c r a t i v e , and i n g e n e r a l t h e r e i s a 15% i n c r e a s e i n seed p r i c e s f o r c e r t i f i e d over common seed.  In the h i g h l y c o m p e t i t i v e markets f o r w h i t e c l o v e r  seed on t h i s c o n t i n e n t and elsewhere a)  a statement  two t h i n g s appear t o be i n demand:  o f seed o r i g i n ( r e f l e c t i n g t h e c l i m a t e and management system  under which i t i s p r o d u c e d ) ,  b) a name, a l o n g w i t h t h e u s u a l h i g h  standards  o f freedom from d i s e a s e and weed seeds t h a t accompany a c e r t i f i c a t e . The use and  i n t e r e s t shown by some phases o f a g r i c u l t u r e i n w h i t e c l o v e r  has d i m i n i s h e d over the y e a r s as the use o f a r t i f i c i a l n i t r o g e n has i n c r e a s e d . With t h e r i s i n g p r i c e s o f f e r t i l i z e r n i t r o g e n t h e w o r l d o v e r , i n t u r n a r e s u l t of the r i s i n g c o s t of petroleum  p r o d u c t s , a g e n e r a l i n t e r e s t i n legumes and  t h e i r n i t r o g e n f i x i n g a b i l i t y i s a g a i n apparent.  I t i s u n l i k e l y that white  c l o v e r w i l l be used i n v e r y h i g h y i e l d i n g g r a s s p a s t u r e s , but i t s a p p l i c a t i o n i n o t h e r s i t u a t i o n s i s i n c r e a s i n g (e.g., range r e h a b i l i t a t i o n , r e v e g e t a t i o n o f m i n i n g s p o i l banks, r o a d s i d e s and o t h e r a p p l i c a t i o n s ) .  Changes i n m a r k e t i n g  p o l i c y , t o g e t h e r w i t h changes i n t h e a g r i c u l t u r a l and n o n - a g r i c u l t u r a l a p p l i c a t i o n s a r e reasons The  f o r t h e C r e s t o n v a l l e y seed i n d u s t r y t o r e a s s e s s i t s r o l e .  s e e k i n g out o f the causes f o r the d e c l i n e i n seed y i e l d and  persist-  ence o f the w h i t e c l o v e r c r o p i n the C r e s t o n v a l l e y i s one o f t h e p r i m a r y o b j e c t i v e s o f t h i s study.  A l t h o u g h the scope o f the s t u d y was b r o a d ,  such as those o f d i s e a s e c o u l d have been more f u l l y e x p l o r e d .  areas  134 The  i n v e s t i g a t i o n into p o s s i b l e insect pests revealed  o f w e e v i l appear i n l a r g e enough p o p u l a t i o n s d e c r e a s e i n seed y i e l d .  that three  t o have a b e a r i n g  on t h e apparent  The c u m u l a t i v e i n j u r y by t h e s e t h r e e w e e v i l  must be o f s i g n i f i c a n c e .  species  species  Such e f f e c t s as lower f l o r e t f e r t i l i t y and seed  damage by t h e a d u l t s and l a r v a e o f t h e c l o v e r seed w e e v i l a r e apparent (see T a b l e 4.3.4.2).  Poor development o f seeds may w e l l r e s u l t from i n t e r r u p t e d  t r a n s l o c a t i o n as a r e s u l t o f l a r v a l f e e d i n g on t h e r o o t s The  (see T a b l e 4.1.4.1).  a c t i o n o f t h e c l o v e r r o o t c u r c u l i o l a r v a e l e a d s t o a weakening o f t h e  s t a n d , weed i n f e s t a t i o n , poor seed f i l l i n g , pathogen e n t r y , p l a n t s t r e s s and and  loss of plant persistence.  seed c r o p , a p p a r e n t l y  The l a c k o f p e r s i s t e n c e i n t h e w h i t e c l o v e r  r e l a t e d to weevil  incidence, renders i t impossible f o r  the farmer t o keep t h e c r o p l o n g e r t h a n one seed h a r v e s t . sequences o f t h i s w i l l habit.  The l o n g - t e r m con-  lead to a n a t u r a l s e l e c t i o n o f p l a n t s f o r a b i e n n i a l  T h i s may w e l l be o f importance t o t h e seed t r a d e because w h i t e c l o v e r  i s normally  a long-lived perennial  i n agricultural practice.  l i k e l y t o be much i n t e r e s t e d i n s t r e s s i n g l a s t i n g The  s a m p l i n g methods a l s o r e v e a l e d  nematodes and r o d e n t s .  The t r a d e i s n o t  persistence.  o t h e r o r g a n i s m s , such as s l u g s ,  These organisms s h o u l d n o t be o v e r l o o k e d  damage t h e y t o o can cause.  f o r the  A l t h o u g h c o n t r o l by c h e m i c a l means i s p o s s i b l e ,  t h e i r p r e s e n c e i n t h e c r o p was o b s e r v e d t o be s p o r a d i c , b o t h i n t i m e and location.  I f e e l t h a t t h e y a r e n o t t h e p r i n c i p a l causes o f t h e g e n e r a l  seed  y i e l d d e c l i n e but a r e c o n t r i b u t o r y . S o i l f e r t i l i t y and r e a c t i o n t e s t s i n d i c a t e d t h a t t h e n u t r i e n t s and hydrogen i o n c o n c e n t r a t i o n s  were n o t l i m i t i n g p l a n t growth.  However, t h e  h i g h s o i l r e a c t i o n and c a l c i u m c o n t e n t l e a d me t o b e l i e v e t h a t t h e r e i s a general  need by C r e s t o n w h i t e c l o v e r f o r e x t r a phosphorus f e r t i l i z e r .  calcium  i o n s combine w i t h t h e a p p l i e d phosphate f e r t i l i z e r t o form p r i n c i p a l l y  d i c a l c i u m phosphate which i s a r e l a t i v e l y u n a v a i l a b l e form t o p l a n t s .  The  In  135 a d j a c e n t a l f a l f a c r o p s , boron d e f i c i e n c y was noted on s e v e r a l o c c a s i o n s ; i t was not noted i n w h i t e c l o v e r  fields.  The s a m p l i n g o f seed and phytomas r e v e a l e d t h a t t h e r e i s a l a r g e v a r i a t i o n i n y i e l d b o t h w i t h i n and between f i e l d s .  Some g e n e r a l t r e n d s were observ  One o f t h e s e t r e n d s t h a t the heavy t o p growth o f w h i t e c l o v e r does not n e c e s s a r i l y mean h e a v i e r seed y i e l d .  I n o t h e r a r e a s where w h i t e c l o v e r i s  grown f o r seed, n o t a b l y B r i t a i n , d e f o l i a t i o n o f the c r o p i n e a r l y summer i s practiced.  Leguminous c r o p s , o t h e r t h a n w h i t e c l o v e r , b e n e f i t from an e a r l y  summer c u t t i n g , which s t i m u l a t e s r e p r o d u c t i v e growth as opposed t o v e g e t a t i v e growth, and which h e l p s c r e a t e a more open s t a n d .  I t was observed t h a t  fifty  p e r c e n t o f t h e v e g e t a t i v e growth a t C r e s t o n t a k e s p l a c e p r i o r t o the end o f May.  A s i m i l a r p r a c t i c e o f v e g e t a t i v e removal e a r l y i n t h e season i n t h e  C r e s t o n v a l l e y may p r o v e b e n e f i c i a l , but a l l o w a n c e i n time must be made f o r a c a r b o h y d r a t e b u i l d - u p f o r seed p r o d u c t i o n . to  Too l a t e a c u t t i n g w i l l  lead  poor seed p r o d u c t i o n . F l o r a l bud i n i t i a t i o n i s s t i m u l a t e d by t h i s p r a c t i c e o f opening up the  stands and i t was observed a t C r e s t o n t h a t the number o f i n f l o r e s c e n c e s s t r o n g l y a s s o c i a t e d w i t h seed y i e l d .  was  Legumes, as p r e v i o u s l y mentioned, f i x  t h e i r own n i t r o g e n , and c o n s e q u e n t l y a h i g h n i t r o g e n l e v e l i s m a i n t a i n e d i n the  soil.  T h i s widens the nigrogen-phosphorus r a t i o .  This r a t i o widening  c r e a t e s a tendency f o r t h e w h i t e c l o v e r p l a n t t o remain i n a v e g e t a t i v e s t a t e , as t h e p h o s p h o r u s - n i t r o g e n - c a r b o n r a t i o s remain wide.  However, by the a p p l i c a  t i o n o f phosphorus t o the seed c r o p , t h i s r a t i o i s narrowed and a b a l a n c e main t a i n e d f o r r e p r o d u c t i v e growth.  By u s i n g phosphorus f o r t h i s purpose we a r e  a b l e t o m a n i p u l a t e a c r o p i n t o r e p r o d u c t i v e growth w i t h o u t l o s i n g i t s g e n e t i c c a p a c i t y f o r v e g e t a t i v e growth. The p o t e n t i a l seed y i e l d s as measured by t h e quadrat method were a l m o s t always l a r g e r than t h o s e o b t a i n e d by the grower.  I n some cases growers  yields  136 were almost h a l f t h a t o f t h e p o t e n t i a l y i e l d . t h a t c o n s i d e r a b l e s h a t t e r i n g and P l a n t s t r e s s can r e s u l t i n  earlij  The  explanation for this  being  seed head l o s s o c c u r s a t t i m e o f h a r v e s t . m a t u r i t y , head and seed l o s s a t h a r v e s t .  I f e e l t h a t p o l l i n a t i o n o f the w h i t e c l o v e r seed c r o p at C r e s t o n i s not a problem.  The  recommendations i n e f f e c t i n o t h e r c o u n t r i e s l e a d t o the con-  c l u s i o n t h a t each f i e l d i n the C r e s t o n v a l l e y had an adequate number o f p o l l i n a t o r hives.  Beehives a r e r o u t i n e l y p l a c e d i n each c r o p o f w h i t e c l o v e r .  In every case measurements o f p e d u n c l e l e n g t h were g r e a t e r t h a n p e t i o l e l e n g t h , e n s u r i n g adequate exposure o f i n f l o r e s c e n c e s f o r bees.  I n the f i e l d i t was  observed t h a t i n f l o r e s c e n c e s were always w e l l above the f o l i a g e . be t h a t i t i s i m p o r t a n t for  good p o l l i n a t i o n .  However, i t was  observed t h a t l o n g s t u b b l e  The  remaining  even weeds o f low s t a t u r e such as  and o f course t a l l weeds such as p e r e n n i a l sow  clover.  dandelion  t h i s t l e appeared to stand w e l l  Such o b s t r u c t i o n s c o u l d l e a d to poor bee a c t i v i t y on the  c l i p p i n g o f weeds i n f i e l d 6 c o u l d be r e s p o n s i b l e f o r the  number o f seeds per head, w h i l e i n f i e l d 5, where t h e r e was  o f t o p growth i n e a r l y summer would l i k e l y d i m i n i s h t a l l weeds. spray coming on the 22nd o f June was about two days.  be  high  A cutting  The  malathion  observed t o d e t e r but not h a l t bee  T h i s s p r a y comes when the crop i s i n f u l l  s m a l l drop i n seed y i e l d may  white  a heavy i n f e s t a -  t i o n o f d a n d e l i o n s , we have a lower seed count per i n f l o r e s c e n c e .  for  well  t o have i n f l o r e s c e n c e s w e l l exposed above the canopy  a f t e r the p r e v i o u s g r a i n h a r v e s t and  above the c r o p .  I t may  activity  bloom and  a  apparent.  T o t a l p l a n t n i t r o g e n (Table 4.4.1) demonstrated t h a t the m a j o r i t y o f n i t r o g e n f i x a t i o n o c c u r r e d p r i o r t o the end o f May. i n p l a n t n i t r o g e n o c c u r s and  In some cases a d e f i c i t  t h i s c o u l d be a r e s u l t o f the f e e d i n g by the  larva  o f the c l o v e r r o o t c u r c u l i o on the p l a n t nodules and r o o t s . The  Kjeldahl nitrogen determination  acetylene-reduction technique  i s not' n e a r l y as s e n s i t i v e as  i n measuring the a b i l i t y o f a p l a n t - s y s t e m  the to  137 "fix"  atmospheric n i t r o g e n .  consequently  The K j e l d a h l a n a l y s i s i s a l s o d e s t r u c t i v e and  does n o t a l l o w f o r r e p e a t e d  observations.  to adapt t h e a c e t y l e n e - r e d u c t i o n t e c h n i q u e  I t took me a l o n g t i m e  t o my c o n d i t i o n s .  With the help o f  Mr.  I l m a r s D e r i c s we c o n s t r u c t e d a p o r t a b l e f i e l d u n i t ( s i m i l a r t o M a l l a r d e t  al.  1977) f o r measuring t h e p r o d u c t i o n o f e t h y l e n e .  r e d u c t i o n technique  The u s e o f t h e a c e t y l e n e -  and f i e l d measurement o f e t h y l e n e produced c o u l d be a  v e r y u s e f u l measure o f t h e e f f e c t by t h e c l o v e r r o o t c u r c u l i o on t h e w h i t e c l o v e r system. The o b s e r v a t i o n s c a r r i e d o u t a t U.B.C. were made l a r g e l y on s i n g l e p l a n t s . The d a t e o f f l o w e r i n g and number o f i n f o r e s c e n c e s produced a r e i m p o r t a n t :  to  f o r a g e seed p r o d u c t i o n .  I t i s i n t h e i n t e r e s t s o f t h e grower t h a t a p l a n t  produces, t h e maximum amount o f seed and t h i s i s one r e a s o n why seed  production  i s o f t e n t o be c a r r i e d o u t i n an a r e a o t h e r t h a n i t s a r e a o f g r e a t e s t .use f o r forage.  As documented, w h i t e c l o v e r i n i t i a t e s  to d a y l e n g t h and t e m p e r a t u r e .  r e p r o d u c t i v e growth i n response  White c l o v e r i s a l o n g day s p e c i e s and d i f f e r e n t  s t r a i n s respond i n t h e i r f l o w e r i n g t o d i f f e r e n t c o m b i n a t i o n s o f t e m p e r a t u r e and daylength.  I t appears from one y e a r ' s  information that the Creston  strains  a r e w e l l adapted t o t h e l a t i t u d e f o r seed p r o d u c t i o n . L e a f a r e a and p e t i o l e l e n g t h i n w h i t e c l o v e r a r e i m p o r t a n t c a t e g o r i z e s t r a i n s as t o t h e i r v a r i o u s f o r a g e uses.  i n helping to  To e l a b o r a t e , L a d i n o  c l o v e r , which has a l a r g e l e a f a r e a and p e t i o l e l e n g t h , i s used f o r hay and g r a z i n g p a s t u r e s where t h e a b i l i t y essential.  short-term  t o w i t h s t a n d heavy g r a z i n g i s n o t  However, t h e w i l d w h i t e c l o v e r s w i t h t h e i r s m a l l l e a f a r e a and  p e t i o l e l e n g t h a r e s u i t e d t o a r e a s o f low f e r t i l i t y and have t h e a b i l i t y t o p e r s i s t a l m o s t i n d e f i n i t e l y under heavy g r a z i n g .  I n my t r i a l on twenty s t r a i n s  I found t h a t t h e Japanese s t r a i n "Tohoku" i s o f t h e l a r g e - l e a v e d w h i t e c l o v e r w h i l e t h e Dutch s t r a i n " B a r b i a n " i s s m a l l - l e a v e d .  intermediate  138 L e a f markings o f the i n v e r t e d "V" on w h i t e c l o v e r p l a n t s i n my  trial  c o u l d be made between s t r a i n s .  t y p e and the a n t h o c y a n i n f l e c k i n g found  v a r i e d c o n s i d e r a b l y , but l i t t l e  However, the L o u i s i a n a s t r a i n s stood out  t h e i r c o n s i s t e n t p r e s e n c e o f the i n t e n s e "V" from warmer c l i m a t e s .  The  distinction  l e a f mark.  by  These are s t r a i n s  a n t h o c y a n i n marks, which a r e e x p r e s s e d t o a g r e a t e r  extent under c o o l e r t e m p e r a t u r e s , show a g a i n t h a t the s t r a i n s from the warmer c l i m a t e s f a v o u r t h e i r absence.  The  contingency  the independent i n h e r i t a n c e , o f the two  t a b l e (Table 4.9.5.6) shows  l e a f marks, from each o t h e r .  The measure of c y a n o g e n e s i s , because o f the n e g a t i v e r e a c t i o n s i n the s t r a i n s from the C r e s t o n v a l l e y , appears to be o f l i t t l e use.  However, i f the  D a n i s h s t r a i n " P a j b e r g m i l k a or K i v i " were b e i n g grown, t h e n the t e s t c o u l d be o f use due  t o i t s o c c a s i o n a l cyanogenic r e a c t i o n .  Again,  as has  documented i n the l i t e r a t u r e , s t r a i n s grown i n warmer c l i m a t e s  been  ( v i z . i n our  t r i a l s L o u i s i a n a s t r a i n s ) were c y a n o g e n i c . P l a n t weight d i d not s e p a r a t e the second h a r v e s t p l a n t weight was  out s t r a i n s i n the f i r s t c u t ; however, i n u s e f u l i n s e p a r a t i n g out s t r a i n s t h a t  have a good f a l l r e c o v e r y a f t e r d e f o l i a t i o n .  T h i s was  w e l l d i s p l a y e d by  L o u i s i a n a s t r a i n s which had a h e a v i e r weight on the second c u t .  the  It is felt  t h a t t h i s good r e g r o w t h and c y a n o g e n i c r e a c t i o n o f s t r a i n s o f s o u t h e r n o r i g i n can l e a d t o a poor p e r s i s t e n c e i n the more n o r t h e r n  latitudes.  The  Creston  s t r a i n s , w i t h f a l l dormancy-aid s m a l l e r l e a v e s , should d i s p l a y a g r e a t e r degree o f The  hardiness. purpose o f p l a n t i n g the c l o n a l m a t e r i a l was  t o compare the  i n h e r i t e d v a r i a b i l i t y w i t h t h a t o f the p l a n t s produced from seed.  nonThe  measurements o f l e a f a r e a , p e t i o l e l e n g t h , p l a n t h e i g h t and w e i g h t were compared by u s i n g the c o e f f i c i e n t of v a r i a t i o n .  I t was  observed that  e x i s t s s u b s t a n t i a l n o n - i n h e r i t a b l e v a r i a t i o n w i t h i n t h e c l o n a l and  there  seed  m a t e r i a l a t t r i b u t a b l e t o sampling e r r o r , s o i l c o n d i t i o n s o r r o o t damage.  139  Recommendations f o r f u r t h e r work: a)  There s h o u l d be more i n t e n s i v e m o n i t o r i n g o f t h e i n s e c t p o p u l a t i o n s ,  e s p e c i a l l y t h e t h r e e major s p e c i e s o f w e e v i l , w i t h a view t o d e t e r m i n i n g t h e most e f f e c t i v e c o n t r o l s .  T h i s would a l s o i n c l u d e t h e problem o f n o t a f f e c t i n g  the p o l l i n a t o r s . b)  B i o l o g i c a l n i t r o g e n f i x a t i o n s t u d i e s should be c a r r i e d out t o  d e t e r m i n e t h e a b i l i t y o f t h e C r e s t o n w h i t e c l o v e r t o f i x atmospheric n i t r o g e n under f i e l d c o n d i t i o n s . c)  There s h o u l d be t h e development, by i n d i v i d u a l p l a n t s e l e c t i o n , from  t h e p r e s e n t C r e s t o n w h i t e c l o v e r s t o c k s o f named l a n d s t r a i n s .  Domestically,  two needs a r e apparent and two s e p a r a t e s t r a i n s should be c o n s i d e r e d .  First,  an i n t e r m e d i a t e t y p e , s u i t e d t o a hay and g r a z i n g system, w i t h moderate p e r sistence.  Second, a s m a l l - l e a v e d t y p e t h a t i s s u i t e d t o heavy g r a z i n g and  poor edaphic for  and c l i m a t i c c o n d i t i o n s ; t h i s s m a l l - l e a v e d type i s g r e a t l y needed  t h e range and n o n - a g r i c u l t u r a l r e h a b i l i t a t i o n p r o j e c t s o f t h i s p r o v i n c e . d)  The C r e s t o n v a l l e y i s i d e a l l y s u i t e d t o the p r o d u c t i o n o f w h i t e  c l o v e r f o r seed; however, t h e management o f t h e w h i t e c l o v e r c r o p needs revision.  F i r s t , t h e p r a c t i c e o f e a r l y d e f o l i a t i o n i n t h e growing season o f  the f i r s t c l o v e r seed h a r v e s t needs c o n s i d e r a t i o n .  Second, t h e s o i l s o f t h e  C r e s t o n v a l l e y a r e c a l c a r e o u s and t h e c a r r y o v e r o f a v a i l a b l e p h o s p h a t i c f e r t i l i z e r may be i n s u f f i c i e n t f o r optimum r e p r o d u c t i v e growth. warrant  T h i s would  a s p r i n g a p p l i c a t i o n o f superphosphate o r t r i p l e superphosphate t o  the c l o v e r seed c r o p .  These two management t e c h n i q u e s would g r e a t l y a s s i s t  the growers i n p r o d u c i n g  l a r g e r m a r k e t a b l e q u a n t i t i e s o f seed.  140 Literature Cited  A l d r i c h , D.T.A. 1969: C l o v e r r o t ( S c l e r o t i n i a t r i f o l i o r u m ) i n w h i t e c l o v e r and i t s i n f l u e n c e i n v a r i e t a l performance a t d i f f e r e n t c e n t r e s . E d i t e d by Lowe, J . i n White c l o v e r r e s e a r c h pp 143-146. Occas. Symp. No. 6. B r i t . G r a s s l . Soc. 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Recent Advances i n P h y t o c h e m i s t r y 10:229.  150  Ware, W.M. 1925: White c l o v e r . Agr. F i s h , London.  M i s c . p u b l i c a t i o n No. 46. M i n .  W i l l i a m s , R.F., Evans, L.T. and Ludwig, L . J . 1964: E s t i m a t i o n o f l e a f a r e a f o r c l o v e r and l u c e r n e . A u s t r a l i a n J . A g r . Res. 15:231-233. W i l l i a m s , T.E. 1959: Leys and subsequent a r a b l e p r o d u c t i v i t y . meeting o f t h e B r i t . G r a s s l . Soc. PP- 189-194.  Winter  W i l l i a m s , W. 1945: V a r i e t i e s and s t r a i n s o f r e d and w h i t e c l o v e r B r i t i s h and f o r e i g n . S e r i e s H, No. 16:19-26. Welsh P l a n t B r e e d i n g S t a t i o n , Wales. . 1969: White c l o v e r i n B r i t i s h A g r i c u l t u r e . E d i t e d by Lowe, J . i n White c l o v e r r e s e a r c h , pp. 1-10. Occas. Symp. No. 6. B r i t . G r a s s l . Soc. W i l l i s , C.B. and Thompson, L.S. 1977: The e f f e c t s o f r o o t l e s i o n nematodes on y i e l d o f f o r a g e , legumes and g r a s s e s seeded a l o n e and i n m i x t u r e . Can. J . P l a n t S c i . 57:315. W i l s o n , P.W. 1940: The b i o c h e m i s t r y U n i v . Wis. P r e s s .  o f symbiotic  nitrogen  fixation.  W i t t n e b e n , U. and S p r o u t , P.N. 1971: S o i l s u r v e y o f t h e C r e s t o n a r e a : I n t e r i m r e p o r t o f the C r e s t o n V a l l e y s o i l s u r v e y . B r i t . Columbia Dep. A g r . Y e a t e s , G.W. 1976: E f f e c t o f f e r t i l i s e r t r e a t m e n t and s t o c k i n g r a t e on p a s t u r e nematode p o p u l a t i o n s i n a y e l l o w - g r e y e a r t h . New Z e a l . J . A g r . Res. 19:405-408. , H e a l y , W.B. and Widdowson, J . P . 1976: E f f e c t o f a s o i l fumigant on t h e e s t a b l i s h m e n t and growth o f a g r a z e d p a s t u r e on a yellow-brown loam. New Z e a l . J . A g r . Res. 19:397-403. , Ross, D.J., B r i d g e r , B.A. and V i s s e r , T.A. 1977: I n f l u e n c e o f t h e nematodes H e t e r o d e r a t r i f o l i i and Meloidogyne h a p l a on n i t r o g e n f i x a t i o n by w h i t e c l o v e r under g l a s s house c o n d i t i o n s . New Z e a l . J . A g r . Res. 20:401-413. Z a l e s k i , A. 1969: White c l o v e r seed p r o d u c t i o n . E d i t e d by Lowe, J . i n white c l o v e r research, pp. 147-154. Occas. Symp. No. 6. B r i t . G r a s s l . Soc.  F i g u r e 7-1  The C r e s t o n v a l l e y i n s o u t h - e a s t e r n B.C. i s s u i t a b l e f o r the p r o d u c t i o n o f h i g h q u a l i t y w h i t e c l o v e r  F i g u r e 7.2(a)  seed.  White c l o v e r ranks as one o f t h e w o r l d ' s more  important  forage p l a n t s . . . . i t s a p p l i c a t i o n i n other s i t u a t i o n s i s increasing  ( v i z . range r e h a b i l i t a t i o n ) .  F i g u r e 7.2(c)  F o r e s t e d range  F i g u r e 7.3(b)  C r e s t o n s t r a i n s , w i t h l e s s f a l l r e c o v e r y i n t o growth, should d i s p l a y a greater p e r s i s t e n c e .  Figure  7.4(c)  F i g u r e 7.4(d)  .even weeds o f low s t a t u r e such as d a n d e l i o n s .  ....and o f course t a l l weeds such as p e r e n n i a l sow thistle.  F i g u r e 7-5(b)  . . . . l o n g s t u b b l e r e m a i n i n g a f t e r the p r e v i o u s y e a r ' s g r a i n h a r v e s t . . . such o b s t r u c t i o n s c o u l d l e a d t o poor bee  activity.  F i g u r e 7.7(a)  ....white c l o v e r i n c e r t a i n areas o f d i f f e r e n t t e x t u r e would f l o w e r p r e m a t u r e l y .  soil  Figure  7.7(b)  F i g u r e 7-7(c)  F l o w e r i n g i n e a r l y June  Matured by l a t e June  F i g u r e 7.8  The average number o f i n f l o r e s c e n c e s p e r h e c t a r e was e s t i m a t e d t o be 11.5  F i g u r e 7-9  million.  ....beehives are r o u t i n e l y p l a c e d i n each c r o p o f w h i t e clover.  F i g u r e 7.10(a)  . . . . h a r v e s t i n g g e n e r a l l y commences when 90% o f t h e heads a r e "brown".  F i g u r e 7.10(b)  ....farmers a r e e x p e r i e n c i n g a seed l o s s , w h i l e h a r v e s t i n g , o f up t o S 0 % .  Figure 7 - l l ( l )  . . . . i t i s i m p o s s i b l e f o r t h e farmer t o keep t h e crop l o n g e r than one seed h a r v e s t .  Figure  7.11(b)  C h i s e l ploughed  Figure  7-13  white different ferent  clover  is  a s h o r t - l o n g day s p e c i e s  s t r a i n s respond i n t h e i r f l o w e r i n g to  combinations of temperature  and  and dif-  day-length.  Figure 7 - l M b )  ...the p e t a l s are w h i t e but  are o c c a s i o n a l l y  pink.  F i g u r e 7.15(a)  . . . L o u i s i a n a s t r a i n s s t o o d out by t h e i r c o n s i s t e n t p r e s e n c e o f t h e i n v e r t e d "V" l e a f mark.  F i g u r e 7.15(b)  P l a n t s w i t h no l e a f markings were i n t h e m i n o r i t y .  

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