LEAF AND STEM ANATOMY THEIR OF SEVERAL COMPACT ALAR APPLE MUTANTS, TREATED CULTIVARS, AND PLANTS by ALICE CHEN-MIAO LIU B.S.A., Taiwan P r o v i n c i a l Chung-Hsing U n i v e r s i t y , A THESIS THE SUBMITTED IN REQUIREMENTS MASTER PARTIAL FOR OF THE FULFILMENT DEGREE OF SCIENCE IN THE DEPARTMENT of PLANT SCIENCE We accept t h i s t h e s i s as to the r e q u i r e d standard THE UNIVERSITY OF March, 1970 conforming BRITISH COLUMBIA 1967 OF In p r e s e n t i n g t h i s t h e s i s in p a r t i a l f u l f i l m e n t o f the requirements an advanced degree at the U n i v e r s i t y of B r i t i s h C o l u m b i a , I agree the L i b r a r y s h a l l make i t f r e e l y I f u r t h e r agree tha available for r e f e r e n c e and permission for extensive copying of t h i s It i s understood that copying o r thesis permission. Department The U n i v e r s i t y o f B r i t i s h Columbia Vancouver 8, Canada or publication o f 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 not be a l l o w e d w i t h o u t my written that study. f o r s c h o l a r l y purposes may be g r a n t e d by the Head of my Department by h i s r e p r e s e n t a t i v e s . for ABSTRACT Naturally occurring compact (spur type) a p p l e t r e e s s y l v c s t r i s L.) were compared w i t h s t a n d a r d and A l a r Stem anatomy r e c e i v e d (Malus treated trees. s p e c i a l a t t e n t i o n because no comparisons had been done o f the stem anatomy Anatomical studies of leaves i n s t a n d a r d and compact a p p l e i n compact mutants and i n A l a r Red D e l i c i o u s a r e more d e t a i l e d than i n e a r l i e r Four c u l t i v a r s were used i n the s t u d i e s . trees. treated reports. They were H a r r o l d Red D e l i c i o u s , a compact mutant o f Red D e l i c i o u s , namely S t a r k r i m s o n , and s t a n d a r d Golden D e l i c i o u s , and i t s compact mutant S t a r k s p u r . There were t h r e e main s t u d i e s i n t h i s i n v e s t i g a t i o n . I n the f i r s t study, a n a t o m i c a l e x a m i n a t i o n s were made on the f o u r c u l t i v a r s without A l a r treatment. S t a r k s p u r Golden D e l i c i o u s was to have the t h i c k e s t l e a f and p a l i s a d e tivars studied. palisade The compact type was parenchyma and g r e a t e r w i t h the s t a n d a r d parenchyma among the f o u r found to have a t h i c k e r mean p a l i s a d e cul- leaf, number when compared type. The e f f e c t of A l a r a t c o n c e n t r a t i o n s same c u l t i v a r s was i n v e s t i g a t e d of t e r m i n a l found o f 0 and 1000 ppm on the i n the second study. growth by A l a r v a r i e d among the c u l t i v a r s . The suppression The response to A l a r was g r e a t e s t w i t h S t a r k s p u r and 50 per cent i n h i b i t i o n of shoot growth was o b s e r v e d . atment. Microscopic S t a r k r i m s o n was n o t a f f e c t e d by A l a r examination revealed cant d i f f e r e n c e s i n c e l l t h a t t h e r e were no tre- signifi- l e n g t h of c o l l e n c h y m a , parenchyma and pith ii c e l l s o r i n c e l l d i a m e t e r s and t i s s u e t h i c k n e s s taken from the f i r s t I n study t h r e e , when the samples were i n t e r n o d e under the growing t i p . the e f f e c t o f A l a r and i t s i n t e r a c t i o n w i t h g i b b e r e l l i c a c i d on Red and Golden D e l i c i o u s were c o n s i d e r e d . In this study, comparisons were a l s o made w i t h the u n t r e a t e d compact mutants. Alar t r e a t m e n t s o f Red D e l i c i o u s were found t o i n c r e a s e total l e a f , spongy parenchyma and the l e n g t h latter two a c c o u n t e d f o r the i n c r e a s e t r e a t e d Red D e l i c i o u s Gibberellic acid and of palisade i n t o t a l thickness cells. The of Alar- leaves. stimulated t h e shoot growth o f Golden S t a r k s p u r by 29 per c e n t , b u t t h i s s t i m u l a t i n g t e d by A l a r . thickness of Delicious e f f e c t was preven- ACKNOWLEDGEMENTS I w i s h t o express my deepest g r a t i t u d e t o Dr. G. W. Eaton, Associate Professor, Department o f P l a n t S c i e n c e , University of B r i t i s h Columbia, under whose s u p e r v i s i o n t h i s p r o j e c t was undertaken, f o r h i s t e c h n i c a l advice the p r e p a r a t i o n during the r e s e a r c h , and f o r h i s guidance i n of t h i s thesis. S i n c e r e a p p r e c i a t i o n i s e s p e c i a l l y expressed t o Dr. N. E. Looney, P o m o l o g i s t , Canada Department o f A g r i c u l t u r e R e s e a r c h S t a t i o n , Summerland, B r i t i s h Columbia, who k i n d l y provided many o f the p l a n t m a t e r i a l s used i n t h i s p r o j e c t and who a l s o gave v a l u a b l e assistance counsel and i n s e v e r a l ways. A l s o a p p r e c i a t i o n i s extended t o Drs. K. Beamish, C. A. Hornby, and V. C. R u n e c k l e s f o r t h e i r h e l p f u l s u g g e s t i o n s d u r i n g this endeavor. T h i s Research was supported by NRCC O p e r a t i n g Grant A2023 awarded to Dr. G. W. Eaton. V TABLE OF CONTENTS Page I. II. III. IV. INTRODUCTION LITERATURE MATERIALS 1 REVIEW AND .' 3 METHODS 12 RESULTS Experiment 20 1: Comparisons o f U n t r e a t e d Compact and Standard A p p l e C u l t i v a r s Experiment 11: . . . E f f e c t s o f A l a r on Compact and Standard A p p l e C u l t i v a r s Experiment 111 ( a ) : Comparisons 30 o f Compact w i t h A l a r t r e a t e d Red D e l i c i o u s Experiment 20 38 111 ( b ) : E f f e c t s o f A l a r and G i b b e r e l l i c A c i d on Compact and Standard Golden D e l i c i o u s V. VI. 43 DISCUSSION 48 SUMMARY 53 BIBLIOGRAPHY 55 APPENDIX 59 vi LIST OF TABLES Table Page 1. T h i c k n e s s o f L e a f T i s s u e s o f Four C u l t i v a r s 21 2. T h i c k n e s s o f L e a f T i s s u e s of.Red D e l i c i o u s and Golden D e l i c i o u s 3. . 25 T h i c k n e s s o f L e a f T i s s u e s of Standard and Compact Types 4. 26 C e l l Lengths o f Stem Collenchyma, Parenchyma and P i t h o f Four Apple C u l t i v a r s 5. T h i c k n e s s o f Stem C o r t e x , V a s c u l a r T i s s u e , 29 Diameters of P i t h and Stem o f Four Apple C u l t i v a r s 6. 31 C e l l Diameters o f Stem Collenchyma, Parenchyma and P.ith o f Four A p p l e C u l t i v a r s 7. 32 E f f e c t o f A l a r on Shoot Growth of Red D e l i c i o u s and S t a r k r i m s o n 8. 33 E f f e c t o f A l a r on L e a f Number o f Red D e l i c i o u s and S t a r k r i m s o n 9. 34 E f f e c t o f A l a r on Average L e a f Length and Width of Red D e l i c i o u s and S t a r k r i m s o n 10. 35 I n f l u e n c e o f A l a r on Shoot Growth o f S t a r k s p u r and Golden D e l i c i o u s . 11. E f f e c t o f A l a r on L e a f Number o f Golden D e l i c i o u s 12. I n f l u e n c e o f A l a r on T h i c k n e s s of L e a f T i s s u e s of Four A p p l e C u l t i v a r s 3§ a . . . 37 39 vii Table 13. Page Influence of A l a r on Parenchyma and 14. Influence Tissues 15. E f f e c t of A l a r on and 16. Red Influence Influence 40 the T h i c k n e s s of L e a f Delicious 41 Shoot Growth of Starkrimson Delicious of A l a r and of L e a f T i s s u e s 17. P i t h of Four A p p l e C u l t i v a r s of A l a r on of Red the C e l l Lengths of Collenchyma, 45 G i b b e r e l l i c A c i d on of S t a r k s p u r and of A l a r and Thickness Golden D e l i c i o u s . . . 46 G i b b e r e l l i c A c i d on Mean Shoot Growth of S t a r k s p u r and Golden D e l i c i o u s . . . . 47 viii LIST OF FIGURES Figure Page 1. T h i c k n e s s of L e a f T i s s u e s of Four Apple C u l t i v a r s 2. The L e a f C r o s s S e c t i o n of S t a r k s p u r Showing Longer . . . . 22 P a l i s a d e C e l l s and G r e a t e r Mean P a l i s a d e Number Than i n the Standard 3. Golden D e l i c i o u s 23 The L e a f C r o s s S e c t i o n of S t a r k r i m s o n Showing G r e a t e r L e a f T h i c k n e s s Than i n Red D e l i c i o u s 4. 24 L o n g i t u d i n a l S e c t i o n o f Red D e l i c i o u s Stem Showing Collenchyma, Parenchyma, V a s c u l a r T i s s u e and P a r t of P i t h 5. C r o s s S e c t i o n of Red D e l i c i o u s Stem Showing P a r t o f 6. Collenchyma, Parenchyma, V a s c u l a r T i s s u e and P i t h Red D e l i c i o u s Leaves T r e a t e d w i t h A l a r a t 4000 ppm Were T h i c k e r Than U n t r e a t e d Leaves 27 . . . 28 42 INTRODUCTION Due t o the c o s t o f l a b o r i n p r u n i n g and h a r v e s t i n g on l a r g e t r e e s , c o n t r o l l i n g the s i z e o f f r u i t fruit t r e e s has h e l d the i n t e r m i t t e n t i n t e r e s t o f pomologists f o r hundreds o f y e a r s . A r e c e n t approach t o a t t a i n i n g t r e e s i z e c o n t r o l has i n v o l v e d growth r e t a r d a n t s . trees One showing c o n s i d e r a b l e grown chemical promise f o r use on f r u i t i s s u c c i n i c a c i d 2,2-dimethyl h y d r a z i d e commercially known and h e r e a f t e r r e f e r r e d t o as A l a r . The f i r s t p u b l i s h e d of t h i s c h e m i c a l as a growth r e t a r d a n t r e p o r t of the use on p l a n t s was made by R i d d e l l et a l . (31) i n 1962. Studies been r e p o r t e d on the movement and f a t e of A l a r i n a p p l e s e e d l i n g s (25). Other s t u d i e s have shown t h a t A l a r a p p l i e d to a p p l e t r e e s caused many d e s i r a b l e e f f e c t s without a major of r o o t growth ( 3 ) . bloom one to t h r e e days and has a l s o been r e p o r t e d fruit s e t ( 1 4 ) , improve f r u i t - k e e p i n g q u a l i t y ( 1 4 ) , reduce drop ( 1 4 ) , and i n c r e a s e fruit to increase pre-harvest c o l o r ( 2 1 , 23, 3 3 ) . Treatments r e s u l t i n s m a l l e r and f i r m e r f r u i t (5) and greener and t h i c k e r often leaves 16, 17). I n s p i t e of such wide-spread a t t e n t i o n on a d i v e r s i t y o f subjects, there is little detailed information on a n a t o m i c a l e f f e c t s o f A l a r (16) o r a n a t o m i c a l comparisons between s t a n d a r d The and suppression A l a r suppresses t e r m i n a l growth ( 3 , 4, 14, 16), delays (14, have object standard of the p r e s e n t and compact types. study was to f u r t h e r compare compact types and the e f f e c t s o f a l a r on the morphology . 2 and anatomy of a p p l e leaves and stems u s i n g s t a n d a r d and compact s t r a i n s of Red D e l i c i o u s and Golden D e l i c i o u s a p p l e s . LITERATURE The REVIEW development of p l a n t growth r e t a r d a n t s has s i n c e the r e p o r t i n 1949 t h a t a new been v e r y r a p i d c l a s s of c h e m i c a l s , t i n i u m s , reduced stem e l o g a t i o n of bean p l a n t s without changes. The most a c t i v e compound was When a p p l i e d i n one per cent l a n o l i n paste, the f i r s t found to be one-quarter of the control (28). year a number of quaternary l a t e r , Wirwile other internode l e n g t h of of the the and M i t c h e l l (39) r e p o r t e d that ammonium carbamates r e t a r d e d the growth and development of a broad v a r i e t y of p l a n t s p e c i e s without ment of malformed formative 2,4-dichlorobenzyInicotinium. t r e a t e d p l a n t s was One the n i c o - l e a v e s , stems, r o o t s and flowers. the develop- 4-Hydroxy-5~iso~ propyl-2-methylpheny1 t r i m e t h y l ammonium c h l o r i d e , 1 - p i p e r i d i n e c a r boxy l a t e (Amo-1618) was group of chemicals found to be tested. the most a c t i v e compound i n t h i s I n 1958, 2,4-dichlorobenzyl-tributylphosphonium the growth of more w i d e l y in 1960 (2-chloroethy1) P r e s t o n and L i n k (30) found c h l o r i d e (Phosfon) a f f e c t e d d i f f e r e n t species than d i d Amo-1618. trimethylammonium c h l o r i d e (CCC) was to r e t a r d the growth of a l a r g e r number of s p e c i e s than any e a r l i e r compounds ( 3 6 ) . sprays I n 1962, that R i d d e l l e t a l . (32) Then found of reported the that of N-dimethylamino maleamic a c i d (CO 11) r e t a r d e d the growth of legumes, v i n e c r o p s , potatoes and C011 i n aqueous s o l u t i o n , i t s analogue, was found to be u n s t a b l e ornamental p l a n t s . dimethylaminosuccinamic a c i d (B995), was s t a b l e and However, whereas retarded the N- growth of the B995 was discoverer, United B-9, same s p e c i e s as d i d C011 the o r i g i n a l e x p e r i m e n t a l code number g i v e n by Uniroyal, ornamentals and Later the name was O r i g i n a l l y the m a t e r i a l was the shortened to B-Nine, i n t e n d e d f o r use s o l d f o r t h i s purpose under the name of B-Nine. l a t e r commercial p r e p a r a t i o n , species the then the Naugatuck Chemical D i v i s i o n of S t a t e s Rubber Company. DMAS and A l a r . several (13). of f r u i t Alar-85, crops. The i s r e g i s t e r e d f o r use on The on c h e m i c a l s t r u c t u r e i s as follows: 0 II CHo - I CH - 2 C C - NH - N' CHr; - OH II 0 Among the growth r e t a r d a n t s tested, Alar been s t u d i e d by many i n v e s t i g a t o r s . sweet c h e r r i e s , a p p l e s e e d l i n g s have been s t u d i e d (33, new sweet c h e r r y , leaves of the 26). and the Martin i n P h a r b i t i s plants et al. seedlings. resistant (26) were a b l e movement and in f a t e of A l a r short-day p l a n t , P h a r b i t i s n i l , r e s i d u a l A l a r was Prunus avium, i n the spring (40). persistence following A l s o , by to f o l l o w using labeled A l a r , the movement of A l a r i n a p p l e to breakdown i n the p l a n t and t r a n s p i r a t i o n stream. was of t h i s growth r e - From c h e m i c a l a n a l y s i s they concluded t h a t i t r a p i d l y i n the found i n With r a d i o a c t i v e B995, Z e e v a a r t to demonstrate the m o b i l i t y and tardant has Ryugo r e p o r t e d a l a t e f a l l a p p l i c a t i o n (33). able The seems v e r y p r o m i s i n g , and was Due absorbed and was translocated to i t s r a p i d a b s o r p t i o n and 5, h i g h m o b i l i t y , coverage should be o f l e s s importance and a more approach t o a p p l i c a t i o n may be i n o r d e r . over many o t h e r chemical casual T h i s i s an advantage o f A l a r sprays. Once w i t h i n the p l a n t , A l a r causes a number o f e f f e c t s . The e f f e c t on r o o t growth of one year o l d a p p l e t r e e s was s t u d i e d by Barden (3) who r e p o r t e d retardants t h a t the m e r i t o f A l a r over some o t h e r growth i s t h a t A l a r causes many d e s i r a b l e e f f e c t s on the above ground p o r t i o n s of an a p p l e t r e e w i t h o u t a major s u p r e s s i o n of r o o t growth. Other workers have s t u d i e d the e f f e c t o f A l a r on Zeevaart reported t h a t treatment o f the short-day B995 r e s u l t e d i n s h o r t , t h i c k i n t e r n o d e s the (16) plant P h a r b i t i s with The e f f e c t of A l a r on shoot diameter o f a p p l e t r e e s has a l s o been noted. reported t h a t A l a r treatment i n c r e a s e d Golden D e l i c i o u s and Y o r k I m p e r i a l apples. former was due t o an i n c r e a s e i n r a d i a l and (40). cortex. thicker. F o r York I m p e r i a l , Longitudinal shoots. Halfacre et a l . stem r a d i u s o f both The i n c r e a s e d thickness r a d i u s i n the o f the p i t h , i t was due to p i t h and c o r t e x phloem being sections of A l a r - t r e a t e d plants of both apple c u l t i v a r s had fewer and s h o r t e r c e l l s per i n t e r n o d e . was a f f e c t e d more than c e l l Cell division expansion t r a n s v e r s e l y and l o n g i t u d i n a l l y . S e v e r a l workers have noted e f f e c t s of A l a r on f l o w e r i n g o f f r u i t trees. B a t j e r et al. (4) r e p o r t e d t h a t a p p l e and c h e r r y trees w i t h A l a r i n the e a r l y summer o f 1962 produced more f l o w e r s than unsprayed t r e e s . " V i o l e t " , flower sprayed i n 1963 However, i n the short day p l a n t P h a r b i t i s n i l , formation was i n h i b i t e d by the a p p l i c a t i o n o f A l a r 6 via the r o o t s night (40). f o r a period o f 24 hours p r i o r to one i n d u c t i v e E d g e r t o n e t a_l. r e p o r t e d promoted on t h r e e year o l d D e l i c i o u s long t h a t f l o w e r bud f o r m a t i o n was trees sprayed w i t h B995. The pre-bloom a p p l i c a t i o n o f B995 on mature t r e e s d e l a y e d bloom one to t h r e e days and r e s u l t e d i n h i g h e r f r u i t c o n t r o l when f r o s t s o c c u r r e d f o l l o w i n g reports indicated fruit. E d g e r t o n _et aj.. found t h a t Delicious trees s e t as compared w i t h unsprayed the treatments (14). Several t h a t A l a r a l s o a f f e c t e d k e e p i n g q u a l i t y o f the sprays of B995 on three year o l d e a r l y i n the growing season reduced f r u i t size at h a r v e s t (14) and p r e - h a r v e s t s p r a y s o f B995 to more mature M c i n t o s h apple trees resulted i n firmer fruit than on u n t r e a t e d p l a n t s . Other workers have demonstrated the e f f e c t s o f A l a r on enhancing a p p l e q u a l i t y a t h a r v e s t and a f t e r storage ( 1 5 ) . When A l a r was a p p l i e d a t a c o n c e n t r a t i o n cherry the o f 2000 ppm to sweet Prunus avium, e a r l y p r o d u c t i o n of the a n t h o c y a n i n pigments i n f r u i t was observed and Ryugo (33) concluded t h a t a l t h o u g h A l a r enhanced the b i o s y n t h e s i s o f a n t h o c y a n i n s , i t d i d not measurably advance the p h y s i o l o g i c a l m a t u r i t y o f c h e r r i e s . reports that e a r l y season a p p l i c a t i o n of A l a r meters o f sweet c h e r r y The Looney, however, promotes s e v e r a l para- maturity (24). e f f e c t of post-bloom a p p l i c a t i o n of A l a r on a p p l e r i p e n i n g has a l s o been s t u d i e d . Looney (21) r e p o r t e d that fruit the amount of c h l o r o p h y l l i n p e e l and f l e s h o f a p p l e was lower through the season when a spray o f 4000 ppm of A l a r was a p p l i e d i n mid-May, two weeks a f t e r bloom but he delay maturity. concluded t h a t A l a r d i d not n o t i c e a b l y advance or He also studied under storage c o n d i t i o n s and 2000 ppm significantly Alar the r e s p i r a t o r y b e h a v i o r of a p p l e s found t h a t a m i d - J u l y a p p l i c a t i o n of reduced r e s p i r a t i o n of s t o r e d f r u i t 0° C, whereas, a mid-May 2000 ppm r e p o r t from the was d e l a y e d by same l a b o r a t o r y , spray, d i d not treatments of A l a r a p p l i e d two Looney suggests t h a t A l a r w i t h i n the f r u i t and maturity (23). One this counteracted ppm of ethy- biosynthesis r e l a t e d to B a t j e r _et aJL. drop. fruit drop and reported that Winesap a p p l e t r e e s reduced d e l a y e d the development of w a t e r c o r e . Treated somewhat lower i n s o l u b l e s o l i d s ' ( 5 ) . et aJL. thought A l a r might have c e r t a i n s p e c i f i c e f f e c t s than a g e n e r a l e f f e c t on the fruit (8) because they found the a p p l i c a t i o n of A l a r to a p p l e t r e e s i n c r e a s e d delayed best harvest do 100 and of the most noteworthy e f f e c t s of A l a r i s i t s f r u i t s were f i r m e r and rather by suppressed e t h y l e n e the a p p l i c a t i o n of A l a r to D e l i c i o u s and Blanpied later weeks a f t e r bloom, suppression.may not be e x c e l l e n t c o n t r o l " of p r e - h a r v e s t pre-harvest In a t h e . r i p e n i n g of M c i n t o s h a p p l e s t h i s i n h i b i t o r y e f f e c t of A l a r was lene. (21). at fruit firmness date f o r three v a r i e t i e s i n I r e l a n d , but so f o r M c i n t o s h i n New York. They a t t r i b u t e the that and did not conflicting r e s u l t s to d i f f e r e n c e s i n the i n t e r a c t i o n of v a r i e t y , season, l o c a t i o n and the s p e c i f i c e f f e c t s of the Various ported. e f f e c t s of A l a r on material. l e a f c h a r a c t e r i s t i c s have been r e - Edgerton and Hoffman r e p o r t e d spray to t h r e e - y e a r - o l d t h a t A l a r a p p l i e d as a D e l i c i o u s t r e e s i n mid-June produced foliar leaves 8 normal and, i n some cases, d a r k e r green and Barden i n v e s t i g a t e d the concentrations. appeared leaves arrangement of the leaves, production and same workers r e p o r t e d s t u d i e d i n other All leaves of treated stimulated a l s o f r e s h and E f f e c t s of A l a r on c u l t i v a r s such as Red because of the i n t i m a t e transverse (16). leaves found t h a t the thickness r e l a t e d to the p h o t o s y n t h e t i c photosyn2 (g/cm fresh cells respira- a l s o r e l a t e d to the growth (7). e f f e c t of a growth s t i m u l a n t , i n p l a n t s has and and of Beakbane concluded t h a t the number of p a l i s a d e t o r y a c t i v i t y of the p a l i s a d e m e s o p h y l l and elongation be leaf structure McClendon s t u d i e d the a f u n c t i o n of t h e i r d e n s i t y p o t e n t i a l of a p p l e r o o t s t o c k s area orchard , per u n i t l e a f s u r f a c e was on Delicious. have s i g n i f i c a n c e i n the rate. and Later, l e a f anatomy should twenty-three d i f f e r e n t s p e c i e s of p l a n t and The palisade dry weights per u n i t r e l a t i o n s h i p between the i t s maximum p h o t o s y n t h e t i c weight) (27). looser I n Golden D e l i c i o u s used on York I m p e r i a l the above f i n d i n g s may t h e t i c r a t e was a t h a t A l a r treatment decreased l e a f area a p p l e t r e e s and of l e a f t i s s u e (17). treated expansion whereas A l a r i n h i b i t e d c e l l d i v i s i o n expansion a t a l l c o n c e n t r a t i o n s York I m p e r i a l of A l a r apple p a l i s a d e c e l l s and spongy parenchyma c e l l s . the lower c o n c e n t r a t i o n s (14). l e a f a n a t o m i c a l responses of They found the p l a n t s were t h i c k e r as a r e s u l t of longer the leaves year o l d t r e e s of Golden D e l i c i o u s and York I m p e r i a l with A l a r at various cell The t h i c k e r i n texture, than the u n t r e a t e d H a l f a c r e and one larger i n size. g i b b e r e l l i c a c i d (GA), o f t e n been i n v e s t i g a t e d . As on t h e r e was stem no evidence of c e l l elongation f o r a t l e a s t 72 hours a f t e r a p p l i c a t i o n of g i b b e r e l l i n to the v e g e t a t i v e , p l a n t s of the b i e n n i a l short-day Hyoscyamus and of t h a t the i n i t i a l in the long-day p l a n t Salmolus, Sachs _et al. increase c e l l number (34). i n stem l e n g t h was due Beakbane suggested t h a t GA p o s s i b l e expanding agent i n l e a f t i s s u e subjected (6), 0.5 because i n a p p l e l e a f d i s c s t r e a t e d ppm GA, great d i s t r i b u t i o n and concluded s o l e l y to an might be used as a to shade i n a b a s i c medium expansion of the epidermal c e l l s was increase conditions plus observed. shape of m e s o p h y l l c e l l s were a l s o a f f e c t e d by The GA. S e v e r a l workers have examined the i n t e r a c t i o n of A l a r w i t h GA plants. Z e e v a a r t found the i n h i b i t i o n of flower P h a r b i t i s n i l by A l a r c o u l d be g i b b e r e l l i n A3 to the cucumber s e e d l i n g s , Moore (29) GA3 applied to the was shoot t i p was e f f e c t of 25/ug of A l a r a p p l i e d old 1000 able long n i g h t a p p l i c a t i o n of (40). By to demonstrate t h a t ppm and s u f f i c i e n t to completely n u l l i f y s i m u l t a n e o u s l y (29). of potassium g i b b e r e l l a t e (KGA) reduced to l e s s than 50 per t r e a t e d w i t h KGA a l o n e (14). a c t i o n between A l a r and Further GA the When The a t 200 ppm, the three-year- the cent of t h a t made by at shoot shoots However, the r e a l mechanism of i n t e r gibberellins s t i l l s t u d i e s are needed to e l u c i d a t e the i n the using 1 / i g of D e l i c i o u s a p p l e t r e e s were sprayed w i t h a m i x t u r e of A l a r growth was and formation i n completely overcome by plumule b e f o r e the in remains unknown. r e l a t i o n s h i p between A l a r apple. d i f f e r e n c e i n growth h a b i t , chemical c o n t e n t , and p o s i t i o n between S t a r k i n g D e l i c i o u s and the n a t u r a l l e a f com- compact mutant 10 S t a r k r i m s o n have been s t u d i e d e x t e n s i v e l y . I n g e n e r a l , when compared w i t h S t a r k i n g , the mutant i s r e p o r t e d to have s h o r t e r s h o o t s , fewer l a t e r a l s h o o t s , more f r u i t i n g s p u r s , more nodes per f o o t and t h i c k e r leaves w i t h a g r e a t e r depth of p a l i s a d e parenchyma, more dry weight, c h l o r o p h y l l , N, and Ca ( 1 , 37, 3 8 ) . l i z e about the a n a t o m i c a l B e f o r e i t i s p o s s i b l e to g e n e r a l d i f f e r e n c e s between s t a n d a r d and compact t y p e s , comparisons must be made i n o t h e r c u l t i v a r s D e l i c i o u s and i t s compact mutant, S t a r k s p u r . s i d e r e d these such as Golden Only A r a s u (1) has con- l a t t e r two s t r a i n s and he o n l y r e p o r t s data f o r t o t a l l e a f and p a l i s a d e parenchyma t h i c k n e s s . Stem anatomy comparisons between compact and s t a n d a r d growing types have not been made i n any cultivar. S i n c e the n a t u r a l compact mutants have many m e r i t s over the s t a n d a r d growing s t r a i n s and s i n c e A l a r i s r e p o r t e d to cause s i m i l a r changes i n s t a n d a r d a p p l e t r e e s , a c r i t i c a l comparison of the d i f f e - rences and s i m i l a r i t i e s between these two approaches to s i z e c o n t r o l i s required. I n t r i e r i r e p o r t e d t h a t spur type t r e e s and those t r e a t e d w i t h r e t a r d a n t s showed many a n a l o g i e s i n morphology, p h y s i o l o g y , b i o c h e m i s t r y and anatomy ( 1 9 ) . T h i s was based on an e x t e n s i v e review and not c r i t i c a l literature comparisons w i t h i n any s i n g l e experiment. This r e p o r t t h e r e f o r e must be regarded as s e t t i n g up a number of hypotheses which demand i n v e s t i g a t i o n . larities L i k e w i s e , Looney r e p o r t e d t h e r e were s i m i - between compact mutants and s t a n d a r d D e l i c i o u s a p p l e t r e e s t r e a t e d w i t h A l a r ( 2 2 ) . He found S t a r k r i m s o n was a p p r o x i m a t e l y t h a t the net a s s i m i l a t i o n r a t e of twelve p e r cent h i g h e r than t h a t of S t a r k i n g D e l i c i o u s and a s i m i l a r d i f f e r e n c e was S t a r k s p u r and Golden D e l i c i o u s ( 2 2 ) . r e v e a l e d between According retardant to the studied t i c s such as biochemical concerning l i t e r a t u r e , A l a r i s the most p r o m i s i n g growth to d a t e . While i t s e f f e c t s on c e r t a i n c h a r a c t e r i s - growth h a b i t , e x t e r n a l appearance, morphology f u n c t i o n have been s t u d i e d , t h e r e i s no of main p o i n t s a r i s i n g from t h i s stem anatomy i n Red l e a f and Delicious. and geneticccompossible l i t e r a t u r e review w i l l be D e l i c i o u s and and leaf d e t a i l e d a n a t o m i c a l comparisons compact types of Red and Golden While some a n a t o m i c a l e f f e c t s of A l a r on Golden D e l i c i o u s l e a f anatomy i n compact and D e l i c i o u s have a l r e a d y been r e p o r t e d , standard Golden and Red these w i l l be i n c l u d e d i n the study to a l l o w more d i r e c t comparison w i t h the r e s u l t s of earlier studies. any The time i n t h i s study; e f f e c t s of A l a r on stem i n standard comparisons of present at a l l c a r e f u l study. i n v e s t i g a t e d f o r the f i r s t and and t o o l s f o r s i z e c o n t r o l would i n d i c a t e t h a t any i n t e r a c t i o n merits Two information the e f f e c t of A l a r on the n a t u r a l compact mutants. h o r t i c u l t u r a l importance of both growth r e t a r d a n t s p a c t i o n as and Previous compact mutant and superficial. With t h i s workers have not l e a f anatomy s t u d i e s information s t u d i e d stem anatomy i n to date have been r a t h e r i t should be p o s s i b l e to generalize about the a n a t o m i c a l e f f e c t s of A l a r or n a t u r a l compaction upon a p p l e varieties. MATERIALS AND METHODS Experiment I Comparisons of U n t r e a t e d Compact and Standard C u l t i v a r s The l e a f and shoot samples of a p p l e t r e e s were o b t a i n e d from the o r c h a r d of the Canada Department at Summerland. Two of A g r i c u l t u r e Research S t a t i o n v a r i e t i e s , Red D e l i c i o u s and Golden D e l i c i o u s , w i t h s t a n d a r d and compact t y p e s , i . e . H a r r o l d Red D e l i c i o u s each (standard), S t a r k r i m s o n (compact), Golden D e l i c i o u s ( s t a n d a r d ) and S t a r k s p u r (comp a c t ) , were used i n t h i s experiment. old t r e e s were randomly On June 11, 1968, chosen from each c u l t i v a r . North and South s i d e o f each t r e e was One shoot from the sampled by t a k i n g two n e i g h b o r i n g l e a v e s from the middle p a r t of the c u r r e n t y e a r ' s shoot. was t h r e e nine year Each sampled by t a k i n g d i s c s from t h r e e d i f f e r e n t p o s i t i o n s , middle and b a s a l on each s i d e o f the m i d r i b . first i n t e r n o d e below the shoot t i p was l e a f and shin F l u i d apical, From the same shoot, the taken. Each i n t e r n o d e was t r a n s v e r s e l y i n t o two p a r t s f o r b o t h c r o s s and l o n g i t u d i n a l The S o l u t i o n B: cut sections. shoot t i s s u e s were f i x e d i n B e l l i n g s M o d i f i e d Nava- (20) f o r which the formula i s as f o l l o w s : S o l u t i o n A: leaf Chromic a c i d c r y s t a l s 5g Glacial acetic acid 500cc D i s t i l l e d water 320cc Formalin 200cc D i s t i l l e d water 175cc Saponin 3g After fixation, drated the samples were washed w i t h running tap water, dehy- i n an e t h a n o l s e r i e s and embedded i n p a r a p l a s t according procedure of Johansen (20) which i s shown below: Dehydration: 1. 5%, e t h y l a l c o h o l 2. ll%'.;ethyl a l c o h o l 2 hours 3. 18% e t h y l a l c o h o l 2 hours 4. 30% e t h y l a l c o h o l 2 hours 5. approximate 50% a l c o h o l 2 hours o r 6. . ..... . . 5 parts 95% e t h y l a l c o h o l 4 parts Tertiary butyl alcohol 1 part approximate 70% a l c o h o l overnight D i s t i l l e d water 3 parts 957 e t h y l a l c o h o l 5 Tertiary butyl alcohol 2 parts approximate 85% a l c o h o l 95% e t h y l a l c o h o l Tertiary butyl alcohol approximate 95% a l c o h o l Tertiary butyl alcohol approximate 100%-:alcbh6l. or longer parts 3 parts 10 parts 7 parts a t l e a s t 1 hour 95% e t h y l a l c o h o l 9. longer a t l e a s t 1 hour D i s t i l l e d water 8. hours D i s t i l l e d water 0 7. .2 . . . . Tertiary butyl alcohol 9 parts 11 parts a t l e a s t 1 hour 3 parts to the 14 100% 10. ethyl alcohol 1 part Tertiary butyl alcohol 3 changes (one of which should remain o v e r n i g h t ) Infiltration: 1. m i x t u r e of equal and 2. fill Tertiary butyl alcohol s o l i d i f y but not container cool paraplast, the b u t y l a l c o h o l - p a r a f f i n o i l m i x t u r e and the process place sunk to the bottom of replace with twice d u r i n g d i n g each change of f i n a l l y replace with w i l l be just the i n the oven a t once. t r a c e s of a l c o h o l remain and 6. solidified pour o f f the e n t i r e mixture of p a r a f f i n o i l and repeat l e t the completely. about 1 hour a f t e r the m a t e r i a l has vial, 5. of melted p a r a p l a s t and put the m a t e r i a l on top of the cover w i t h 4. a t l e a s t 1 hour a v i a l three-fourth f u l l paraplast 3. p a r t s of p a r a f f i n o i l pure melted the what paraplast. the next 6 hours or so, d i s c a r - paraplast. pure melted p a r a p l a s t and the material ready f o r embedding w i t h i n the next 30 minutes. Embedding: 1. remove the v i a l from the oven, shake the m a t e r i a l to get i t o f f the bottom and q u i c k l y pour i n t o the p l a s t i c mold. 2. add more melted p a r a p l a s t from the 3. w i t h a needle heated s l i g h t l y stock c o n t a i n e r i f necessary. i n the flame, q u i c k l y d i s p o s e p i e c e s of m a t e r i a l i n t o an o r d e r l y arrangement. 4. as soon as the mould can be moved w i t h o u t d i s t u r b i n g the the 15 arrangement of the p i e c e s of m a t e r i a l , t r a n s f e r tbsa v e s s e l of c o l d water. 5. l e t the mold f l o a t u n t i l the s u r f a c e of the p a r a p l a s t becomes sufficiently f i r m to permit p l u n g i n g the mold slowly beneath the s u r f a c e o f the water. 6. l e a v e the molds i n the water f o r h a l f an hour or u n t i l roughly tho- cooled. A f t e r embedding, a l l the l e a f and stem samples were c u t w i t h a r o t a r y microtome a t t e n microns t h i c k n e s s . S e c t i o n s were a f f i x e d to s l i d e s w i t h Haupt's a d h e s i v e ( 1 8 ) , and s t a i n e d w i t h s a f r a n i n and fast green a c c o r d i n g to the schedule d e s c r i b e d by Johansen (20) and shown below: Staining: 1. Xylene - 10 to 15 minutes. 2. Xylene - 100% ETOH (1-1) - 5 minutes. 3. 95% ETOH - 5 minutes. 4. 70% ETOH - 5 minutes. 5. 50% ETOH - 5 minutes. 6. water - wash w e l l . 7. S t o c k w e l l ' s s o l u t i o n - a t l e a s t 24 hours, depending on m a t e r i a l . 8. water - wash w e l l . 9. t a n n i c a c i d - 10 to 15 minutes. 10. water - wash w e l l . 11. ferric 12. water - wash w e l l . c h l o r i d e - s e v e r a l minutes, depending on b l a c k i n g . 16 13. safranin - at least overnight; usually 24 h o u r s . 14. water - wash w e l l . 15. 95% ETOH w i t h 1/2% p i c r i c a c i d - no more than 10 seconds. 16. 95% ETOH w i t h 4-5 drops ammonia 17. 100% ETOH - about 30 seconds. 18. f a s t green s t a i n i n g s o l u t i o n - s t a r t i n g w i t h a 10 second per 100 cc - 2 minutes. immersion. 19. c l o v e o i l ( t o stop a c t i o n of f a s t green) - a few seconds. 20. c l e a r f o r one or two minutes i n : clove oil - 50 cc 100% ETOH - 25 cc Xylene - 25 cc 100 cc 21. The X y l e n e - a t l e a s t 10 minutes. s l i d e s were then examined m i c r o s c o p i c a l l y . was used f o r measuring leaf the c e l l An o c u l a r micrometer l e n g t h and r a d i a l diameter of stem and tissues. The expected mean squares f o r the a n a l y s i s of v a r i a n c e o f t h i s experiment a r e shown i n the Appendix, Experiment T a b l e s 1 to 4. 11 E f f e c t s of A l a r on Compact and Standard C u l t i v a r s (A) A p p l e t r e e s of Golden D e l i c i o u s and S t a r k s p u r on EM V I I r o o t s t o c k s were grown i n a growth chamber a t Summerland. a t 0 and 1000 ppm was a p p l i e d to each c u l t i v a r . D e l i c i o u s had an average shoot l e n g t h 10.6 cm. I n December 1968, A l a r A t t h i s time Golden of 14.25 cm and S t a r k s p u r had There were s i x t r e e s of each treatment and c u l t i v a r . Alar sprays and measurements of shoot l e n g t h and l e a f number were made a t weekly intervals. The 'compact' S t a r k s p u r grew v e r y v i g o r o u s l y and i n f a c t , was not n o t i c e a b l y d i f f e r e n t from Golden D e l i c i o u s when A l a r was not a p p l i e d . However, A l a r appeared S t a r k s p u r than on Golden Shoot to reduce shoot growth more on Delicious. l e n g t h s were measured from the base o f the new shoot to the base of the t i p l e a f c l u s t e r , and l e a v e s were counted from the base up, i n c l u d i n g h a l f - o p e n e d ones a t top of the shoot. were t e r m i n a t e d on F e b r u a r y 4, 1969. The treatments Samples were c o l l e c t e d a t t h a t same time. Sampling and p r e p a r a t i o n procedures were e s s e n t i a l l y i n experiment the same as I , but the second and t h i r d f u l l y expanded l e a v e s below the shoot apex were chosen f o r l e a f sampled were i n i t i a t e d w e l l a f t e r sampling to ensure t h a t the l e a v e s the A l a r treatments were begun. In each t r e e one o r two shoots were used, and t h e r e were s i x t r e e s of each c u l t i v a r randomly a s s i g n e d to each of the treatments and the con- trols . (B) A t o t a l of twenty-four t r e e s of H a r r o l d Red D e l i c i o u s and S t a r k - rimson were used i n t h i s experiment, a l s o a t Summerland. Technical grade A l a r a t 0 o r 1000 ppm was a p p l i e d to s i x t r e e s o f each When f i r s t t r e a t e d , the average of S t a r k r i m s o n , 8 cm. cultivar. shoot l e n g t h of H a r r o l d was 13 cm and A l a r treatments, shoot l e n g t h and l e a f number d e t e r m i n a t i o n s were done once a week f o r e i g h t weeks b e g i n n i n g A p r i l 8, 1969 w i t h H a r r o l d and A p r i l 22, 1969 w i t h S t a r k r i m s o n . Sampling and p r e p a r a t i o n procedures were the same as d e s c r i b e d i n 18 experiment I . The expected mean squares f o r the a n a l y s i s o f variance of t h i s experiment a r e shown i n the Appendix, T a b l e s 5 to 13. Experiment I I I (a) Comparisons of Compact w i t h A l a r In A p r i l , t r e a t e d Red D e l i c i o u s 1969, the s c i o n s o f Red D e l i c i o u s , and S t a r k r i m s o n were g r a f t e d on EM 11 r o o t s t o c k s planted i n p l a s t i c pots. A l l lateral shoots were removed and o n l y one shoot was a l l o w e d to develop on each tree. Twenty-one Red D e l i c i o u s and seven S t a r k r i m s o n t r e e s were used i n t h i s experiment. On June 12, the Red D e l i c i o u s t r e e s had an ave- rage shoot l e n g t h of 35 cm. Technical grade A l a r w i t h a small o f T r i t o n added, was a p p l i e d a t 0, 1000 and 4000 ppm. seven r e p l i c a t e s w i t h i n each treatment. There were The seven S t a r k r i m s o n w i t h an average shoot l e n g t h o f 14.3 cm were l e f t u n t r e a t e d parison. block. amount trees f o r com- A l l t w e n t y - e i g h t t r e e s were randomly arranged w i t h i n one Shoot l e n g t h s were measured a t weekly i n t e r v a l s . ment was t e r m i n a t e d f i v e weeks a f t e r The e x p e r i - treatment. Experiment I I I (b) E f f e c t s of A l a r and G i b b e r e l l i c A c i d on Compact and Standard Golden D e l i c i o u s Four t r e e s each of Golden D e l i c i o u s and S t a r k s p u r were randomly a r r a n g e d w i t h i n each of two b l o c k s . rootstocks grafted i n A p r i l , These t r e e s were a l s o on EM 11 1969 and prepared as d e s c r i b e d above. On June 12, 1969, A l a r a t 0 and 1000 ppm, GA a t 1000 ppm, and GA a t 1000 ppm combined w i t h A l a r a t 1000 ppm were a p p l i e d i n d i v i d u a l l y to single trees within the same b l o c k . Shoot l e n g t h s were measured once 19 weekly f o r s i x c o n s e c u t i v e weeks. lected ion a t the end o f the experiment. The same c o l l e c t i o n and p r e p a r a t - procedures were used as i n experiment I . t h a t o n l y two d i s c s i n experiment I , tions L e a f and shoot samples were c o l - a l o n g the m i d r i b of each l e a f were taken because no s i g n i f i c a n t d i f f e r e n c e s on a l e a f had been found. analysis The one e x c e p t i o n was among the d i f f e r e n t posi- The expected mean squares f o r the of v a r i a n c e of t h i s experiment a r e shown i n the Appendix, T a b l e s 14 to 17. RESULTS Experiment I Comparisons of U n t r e a t e d Compact and Standard A p p l e C u l t i v a r s There were no d i f f e r e n c e s among H a r r o l d Red D e l i c i o u s , Golden D e l i c i o u s and S t a r k s p u r epidermis creased i n the t h i c k n e s s of the upper and lower and spongy parenchyma. parenchyma than the o t h e r Starkrimson, The S t a r k s p u r three c u l t i v a r s had a t h i c k e r p a l i s a d e (Table 1, F i g . 1 ) . The i n - t h i c k n e s s of the p a l i s a d e parenchyma was found to be due to g r e a t e r mean p a l i s a d e c e l l l a y e r number and l e n g t h ( T a b l e 1, F i g . A l t h o u g h the a n a l y s i s of v a r i a n c e 2). showed no d i f f e r e n c e s i n the t o t a l l e a f t h i c k n e s s between H a r r o l d Red D e l i c i o u s and Starkrimson, discri- minant f u n c t i o n a n a l y s i s showed t h a t the c u l t i v a r s ( F i g . 3) d i f f e r e d s i g n i f i c a n t l y a t the f i v e per cent l e v e l . Red and Golden D e l i c i o u s were compared w i t h r e s p e c t to l e a f t i s s u e t h i c k n e s s , p o o l i n g the compact and standard types. D e l i c i o u s was probably and The t h i c k e r p a l i s a d e parenchyma of Golden due to b o t h the g r e a t e r mean number of l a y e r s the l e n g t h o f p a l i s a d e c e l l s (Table 2). A l s o compact and types were compared p o o l i n g the two c u l t i v a r s . found to have t h i n n e r l e a v e s , t h i n n e r p a l i s a d e parenchyma and mean number of p a l i s a d e c e l l In order was smaller l a y e r s than the compact mutant ( T a b l e 3 ) . to i n v e s t i g a t e the cause f o r the t h i c k e r shoots and shorter internodes made o f c e l l Standard type standard i n the compact apple mutants, measurements were s i z e i n the p i t h and c o r t e x , the t h i c k n e s s o f v a s c u l a r t i s s u e as w e l l as stem t h i c k n e s s . F i g u r e s 4 and 5 show l o n g i t u d i n a l TABLE 1 THICKNESS OF LEAF Harrold Red D e l i c i o u s TISSUES OF Starkrimson FOUR CULTIVARS IN MICRONS Golden D e l i c i o u s Starkspur Significance Level 12a 12a 13a 0.1566 75a 82a 0.1999 100b 112a 0.0028 Lower Epidermis 12a Spongy Parenchyma 75a 75a P a l i s a d e Parenchyma 84c 90bc Upper E p i d e r m i s 14a 14a 14a 15a 0.5218 Total 186b 191b 202b 222a 0.0047 Number of P a l i s a d e C e l l Layer 3.0b 3.1b 3.0b 3.3a 0.0015 29 b 29 b 34a 0.0413 Average P a l i s a d e C e l l Length X 33ab w i t h i n a row, means having a l e t t e r i n common a r e not s i g n i f i c a n t l y 5 per cent l e v e l by Duncan's M u l t i p l e Range T e s t . different a t the Leaf thickness in microns FIGURE 2 The l e a f c r o s s s e c t i o n of S t a r k s p u r showing longer p a l i s a d e c e l l s and g r e a t e r mean p a l i s a d e number ( l e f t ) than i n the standard Golden D e l i c i o u s ( r i g h t ) . (381X) u> The leaf c r o s s s e c t i o n of S t a r k r i m s o n ( l e f t ) showing g r e a t e r l e a f Red D e l i c i o u s ( r i g h t ) . (300X) thickness than TABLE 2 THICKNESS OF LEAF TISSUES OF RED DELICIOUS GOLDEN DELICIOUS IN MICRONS Red D e l i c i o u s x Golden D e l i c i o u s x AND Significance Level Lower E p i d e r m i s 12 13 0.0456 Spongy Parenchyma 75 78 0.2317 P a l i s a d e Parenchyma 87 106 0.0008 Upper E p i d e r m i s 14 15 0.2107 188 212 0.0018 Total Number o f P a l i s a d e C e l l Layer Average P a l i s a d e C e l l Length x 3.02 29 mean of standard and 3.19 33 compact types. 0.0039 0.0078 TABLE 3 THICKNESS OF LEAF TISSUES OF STANDARD COMPACT TYPES IN MICRONS AND Standard Compact Lower Epidermis 12 12 0.6533 Spongy Parenchyma 75 79 0.1923 Palisade 92 101 0.0350 14 14 0.7804 195 206 0.0345 Parenchyma Upper Epidermis Total Number o f P a l i s a d e C e l l Layer Average P a l i s a d e C e l l Length 3.0 31 3.2 32 xx Significance Level 0.0013 0.3983 ^ e a n s of theRed D e l i c i o u s and Golden D e l i c i o u s . 'means of the Starkrimson and S t a r k s p u r . 27 COLLENCHYMA PARENCHYMA VASCULAR PITH FIGURE 4 L o n g i t u d i n a l s e c t i o n o f Red D e l i c i o u s stem showing c o l l e n c h y m a , parenchyma, v a s c u l a r t i s s u e , and p a r t o f p i t h . (118 X) TISSUE COLLENCHYMA) ) CORTEX PARENCHYMA ) VASCULAR TISSUE PITH FIGURE 5 C r o s s s e c t i o n o f Red D e l i c i o u s stem showing p a r t o f c o l l e n c h y m a , parenchyma, v a s c u l a r . t i s s u e and p i t h . (60 X) [S3 00 TABLE 4 CELL LENGTHS PITH OF Cultivar OF STEM COLLENCHYMA, PARENCHYMA AND FOUR APPLE CULTIVARS IN MICRONS Collenchyma Harrold 48a Starkrimson Parenchyma Pith 61a 41a 44a 67a 38a Golden 45a 57a 37a Starkspur 41a 51a 38a X W i t h i n a column, means having a l e t t e r i n common are not s i g n i f i c a n t l y d i f f e r e n t a t the 5 per cent l e v e l by Duncan's M u l t i p l e Range T e s t . 30 and c r o s s s e c t i o n s r e s p e c t i v e l y o f Red D e l i c i o u s shoot t i s s u e . were no s i g n i f i c a n t d i f f e r e n c e s i n c e l l There l e n g t h of collenchyma, chyma or p i t h c e l l s among the f o u r c u l t i v a r s ( T a b l e 4 ) . paren- I n stem cross s e c t i o n s , S t a r k r i m s o n had a t h i c k e r v a s c u l a r t i s s u e than the o t h e r cultivars ( T a b l e 5 ) , but the t h i c k n e s s of the c o r t e x , p i t h and stem were not s i g n i f i c a n t l y d i f f e r e n t i n the c u l t i v a r s . The cell meter o f the collenchyma of Red D e l i c i o u s and S t a r k r i m s o n Red was g r e a t e r than t h a t of Golden D e l i c i o u s and S t a r k s p u r . total dia- Delicious Starkspur had a s m a l l e r p i t h c e l l diameter than the o t h e r t h r e e c u l t i v a r s , but the mean diameter of the parenchyma c e l l s d i d not d i f f e r among vars (Table 6). The data p r e s e n t e d i n T a b l e 5 were measured as cultithough each t i s s u e were c i r c u l a r . Experiment 11 E f f e c t s o f A l a r on Compact and Standard A p p l e The shoot growth of Red D e l i c i o u s was by A l a r u n t i l was first 1000 ppm s i x weeks a f t e r Cultivars not s i g n i f i c a n t l y affected treatment, but growth r a t e s u p p r e s s i o n suspected f o u r weeks a f t e r treatment ( T a b l e 7). A l a r at d i d not show any i n h i b i t i n g e f f e c t on the shoot growth of S t a r k r i m s o n ( T a b l e 7). A l a r d i d not s i g n i f i c a n t l y a f f e c t l e a f number ( T a b l e 8 ) , l e a f l e n g t h or w i d t h i n e i t h e r Red D e l i c i o u s or S t a r k r i m s o n ( T a b l e 9 ) . How- ever, i n Golden D e l i c i o u s , was s i g n i f i c a n t i n h i b i t i o n on shoot l e n g t h observed from the second week a f t e r A l a r treatment. to treatment i n c r e a s e d g r a d u a l l y t i l l ment ( T a b l e 10). The d i f f e r e n c e the t e r m i n a t i o n o f the e x p e r i - The e f f e c t of A l a r on S t a r k s p u r shoot growth was due TABLE 5 THICKNESS OF STEM CORTEX, VASCULAR TISSUE, DIAMETERS AND STEM OF FOUR APPLE CULTIVARS IN MICRONS Cultivar Cortex X OF PITH, Vascular Tissue Pith Diameter Shoot Diameter H a r r o l d Red D e l i c i o u s 256a 248b 1073a 2160a Starkrimson 263a 414a 9 73a 2273a Golden D e l i c i o u s 233a 327ab 908a 2006a Starkspur 288a 279b 939a 1950a w i t h i n a column, means s h a r i n g the same l e t t e r a r e not s i g n i f i c a n t l y d i f f e r e n t a t the 5 per cent l e v e l by Duncan's M u l t i p l e Range T e s t . TABLE 6 CELL DIAMETERS OF STEM OF FOUR APPLE Cultivar COLLENCHYMA, PARENCHYMA AND PITH CULTIVARS IN MICRONS Collenchyma H a r r o l d Red D e l i c i o u s 20a Starkrimson Parenchyma Pith 29a 35a 21a 27a 33a Golden D e l i c i o u s 18b 25a 30a Starkspur 18b 25a 26b X W i t h i n a column, means s h a r i n g the same l e t t e r a r e n o t s i g n i f i c a n t l y d i f f e r e n t a t the 5 per cent l e v e l by Duncan's M u l t i p l e Range T e s t . TABLE 7 EFFECT OF ALAR RED DELICIOUS Cultivar Alar Concentration (ppm) Weeks A f t e r 1 Red Delicious ON SHOOT GROWTH OF AND STARKRIMSON (CM) Treatment 2 3 4 5 6 7 8 15g 23f 29 e 35d 43b 50a 55a 44b 0 8h 1000 8h 15g 21f 28e 32de 37cd 41b c X Significance Level 0.0135 Starkrimson 0 12a 18a 26a 33a 40a 45a 45a 1000 14a 24a 30a 38a 42a 45a 47a Significance Level 0.9389 w i t h i n each c u l t i v a r , means having a l e t t e r i n common a r e not s i g n i f i c a n t l y a t the 5 per cent l e v e l by Duncan's M u l t i p l e Range T e s t . x different TABLE 8 EFFECT Cultivar Red Delicious Alar OF ALAR ON LEAF NUMBER OF AND STARKRIMSON Concentration (ppm) RED DELICIOUS Weeks A f t e r 3 4 Treatment 5 6 7 8 0 6 8 11 14 16 18 21 23 1000 6 8 11 14 16 18 20 22 Significance Level 0.5581 Starkrimson 0 8 12 15 18 20 22 23 1000 10 13 17 19 20 23 24 Significance Level 0.7543 Co •P- TABLE 9 EFFECT OF ALAR ON AVERAGE LEAF LENGTH OF RED DELICIOUS AND STARKRIMSON Cultivar Red Delicious A l a r Concentration (ppm) Significance Level L e a f Width 0 10.1 5.3 1000 10.0 4.9 Significance Level Starkrimson Leaf Length AND WIDTH (CM) 0.8042 0.2430 0 12.4 6.1 1000 12.0 5.7 0.2673 0.1551 TABLE 10 INFLUENCE OF ALAR ON SHOOT GROWTH OF STARKSPUR AND GOLDEN DELICIOUS (CM) Cultivar Golden D e l i c i o u s Alar Concentration (ppm) 0 1000 Significance Level 0.0000 Starkspur 0 1000 Significance Level 2 16i Weeks A f t e r Treatment 3 4 5 6 20h 26f 33d 40c 46b 51a 141 16i 19h 23g 27f 30e 33d 13hij 16gh 22ef 31d 41c 47b 52a 9i llij 14hi 16hi 21fg 24ef 26de X 0.0000 w i t h i n each c u l t i v a r , means having a l e t t e r i n common a r e not s i g n i f i c a n t l y a t the 5 per cent l e v e l by Duncan's M u l t i p l e Range T e s t . different Co TABLE EFFECT Cultivar Golden D e l i c i o u s OF ALAR Alar ON LEAF Concentration (ppm) 0; 1000 Significance Level 11 NUMBER OF 1 14f 12g X GOLDEN DELICIOUS Weeks A f t e r Treatment 2 3 4 16.6d 19b 22a 15e 17cd 17.6b 0.0007 ^Sneans having a l e t t e r i n common a r e not s i g n i f i c a n t l y d i f f e r e n t a t the 5 per cent l e v e l by Duncan's M u l t i p l e Range T e s t . 38 q u i t e d i f f e r e n t from e x p e c t a t i o n . during the during the f o u r t h week. hibited 1000 25% (Table ppm number of one of 11). control. no 10). Four weeks a f t e r treatment, show any s i g n i f i c a n t e f f e c t on by the leaf thinner and Starkrimson leaf lamella s i g n i f i c a n t d i f f e r e n c e s between treatments i n I n Golden D e l i c i o u s , the lower e p i d e r m i s and S t a r k s p u r had less total data f o r c e l l fewer p a l i s a d e thinner l e n g t h i n the cells (Table than stem l o n g i t u d i n a l s e c t i o n s the significantly and from the u n t r e a t e d Experiment I I I than the showed longer compared w i t h the t r e a t e d p l a n t s . treated Harrold Golden D e l i c i o u s were not The signifiin untreated parenchyma cell lengths cell in significantly different plants. (a) Comparisons of Compact w i t h A l a r t r e a t e d Red A l a r was of l e n g t h of parenchyma c e l l shorter S t a r k s p u r Golden D e l i c i o u s p l a n t s c o r t e x as pali- d i f f e r e n t treatments i s shown i n collenchyma c e l l s but p i t h were not the 12). A p p a r e n t l y the A l a r t r e a t e d S t a r k r i m s o n p l a n t s had shorter any treated spongy parenchyma, fewer leaf thickness c u l t i v a r s , each w i t h two c o r t e x and in (Table examination of H a r r o l d Treated T a b l e 13. ones. 50% seven v a r i a b l e s measured. sade c e l l s and cantly found However, s i x weeks a f t e r treatment, A l a r i n - A l a r d i d not revealed p l a n t s had four l e s s r e t a r d a t i o n was Starkspur. the The noted s i g n i f i c a n t l y reduced Golden D e l i c i o u s l e a f number Microscopic sections r e t a r d a t i o n e f f e c t was second week a f t e r treatment, but shoot growth by Alar The found to i n c r e a s e the thickness Delicious of t o t a l l e a f , spongy TABLE INFLUENCE Cultivar Red D e l i c i o u s Starkrimson Golden D e l i c i o u s A l a r Concentration (ppm) THICKNESS CULTIVARS Lower Spongy E p i d e r m i s Parenchyma OF LEAF TISSUES (MICRONS) Palisade Parenchyma Upper Epidermis OF T o t a l Pa 1 i sade Avera ge•-• Number Palisade 0 12 76 124 16 226 3 41 1000 11 73 114 15 213 3 39 0 11 81 100 16 208 3 33 1000 11 90 113 15 229 3 36 0 11 77 96 14 198 3 32 10** 81 90 14 195 2.8* 33 0 11 80 97 14 203 3 33 1000 11 71* 89 14 184* 2.9* 31 1000 Starkspur OF ALAR ON FOUR APPLE 12 - • s i g n i f i c a n t a t 5 per cent * * s i g n i f i c a n t a t 1 per cent level. level. TABLE 13 INFLUENCE OF ALAR ON THE CELL LENGTHS OF COLLENCHYMA, PARENCHYMA AND PITH OF FOUR APPLE CULTIVARS (MICRONS) Alar Concentration (ppm) Pith Red Delicious Starkrimson Golden D e l i c i o u s Starkspur 0 33 46 38 42 1000 35 31** 43 33 0 59 54 50 56 1000 53 50 54 42* 0 35 37 37 41 1000 38 34 39 32 - ' s i g n i f i c a n t a t 5 per cent * * s i g n i f i c a n t a t 1 per cent level. level. o TABLE 14 INFLUENCE Cultivar x Spongy Parenchyma Palisade Parenchyma TISSUES Upper Epidermis Total Palisade Number Average Palisade 63ab 78b 16a 168b 3a 26b 10a 71a 87a 16a 184a 3a 30a 4000 10a 69a 90a 16a 186a 3a 30a 0 10a 59b 75b 16a 161b 3a 27b Delicious Red Delicious 1000 Red Delicious Significance Level ALAR ON THE THICKNESS OF LEAF OF RED DELICIOUS IN MICRONS Alar Concentration Lower (ppm) Epidermis Red Starkrimson OF 0 11a 0.8043 0.0342 0.0039 0.7688 0.0062 0.0907 0.0085 W i t h i n each column, means having a l e t t e r i n common a r e not s i g n i f i c a n t l y d i f f e r e n t a t the 5 per cent l e v e l by Duncan's M u l t i p l e Range T e s t . 43 parenchyma and (Table ppm, 14). l e n g t h of p a l i s a d e The were not c e l l i n H a r r o l d Red r e s u l t s from two concentrations d i f f e r e n t from each o t h e r . palisade parenchyma and were not d i f f e r e n t from u n t r e a t e d slightly t h i c k e r spongy parenchyma was and average p a l i s a d e lower e p i d e r m i s and The i . e . 1000 total leaf parenchyma of H a r r o l d Red Delicious and 4000 thickness, Starkrimson D e l i c i o u s , although found i n the latter. The upper p a l i s a d e number were not d i f f e r e n t from t r e a t - ment to treatment, hence the r e s u l t e d from an i n c r e a s e t h i c k e r l e a f of A l a r i n the thickness of t r e a t e d Red Delicious spongy parenchyma and p a l i s a d e parenchyma ( F i g . 6). A l a r i n h i b i t e d shoot growth of Red i n h i b i t i n g e f f e c t was greater 4000 ppm The (Table 15). second week's growth and experiment. A f t e r two D e l i c i o u s a p p l e t r e e s and a t the h i g h e r c o n c e n t r a t i o n , treatment e f f e c t was was still p r e s e n t a t the i . e . at during termination of the the weeks, the growth r a t e of A l a r - t r e a t e d Red l i c i o u s was l e s s than t h a t of S t a r k r i m s o n Red krimson was still Experiment I I I noticeable the smaller D e l i c i o u s although DeStar- i n total size. (b) E f f e c t s of A l a r and Golden D e l i c i o u s There were no G i b b e r e l l i c A c i d on Compact and Standard s i g n i f i c a n t d i f f e r e n c e s between means f o r the thick- ness of Golden D e l i c i o u s l e a f t i s s u e s as a r e s u l t of treatment w i t h A l a r or GA (Table 16). Golden D e l i c i o u s and end However, GA increased mean shoot growth of S t a r k s p u r Golden D e l i c i o u s by of the experiment (Table 17). A l a r a t 1000 ppm 29 per cent by or the A l a r and the GA 44 combination d i d not a f f e c t the shoot growth o f Golden D e l i c i o u s S t a r k s p u r Golden D e l i c i o u s ( T a b l e 17). s t i m u l a t i n g e f f e c t of GA. and Apparently A l a r n u l l i f i e d the TABLE 15 EFFECT OF ALAR STARKRIMSON AND Cultivar Alar Concentration (ppm) ON SHOOT GROWTH OF RED DELICIOUS (CM) Red Delicious 0 36h Red Delicious 1000 Red Delicious Starkrimson Weeks A f t e r 2 3 1 Treatment 4 5 6 47ef 54c 59b 63a 66a 36h 45 gh 48ef 50de 52cd 54c 4000 34i 42gh 45fg 46f 47ef 48ef 0 14m 211 25kl 28jk 31j 33i Significance Level f o r Interaction x 0.0000 ^ e a n s h a v i n g a l e t t e r i n common a r e not s i g n i f i c a n t l y d i f f e r e n t a t the 5 per cent l e v e l by Duncan's M u l t i p l e Range T e s t . TABLE 16 INFLUENCE OF LEAF Cultivar Golden Treatment (ppm) Lower Epidermis Spongy Parenchyma Palisade Parenchyma Upper Epidermis control 11 70 93 15 189 3 32 A - 1000 11 65 89 15 180 3 33 GA - 1000 11 54 85 16 166 3 28 A - 1000, GA - 1000 10 58 86 15 169 3 31 control 11 66 90 14 182 3 31 A - 1000 11 60 88 15 174 3 31 GA - 1000 12 61 87 15 175 3 29 A - 1000, GA - 1000 12 72 94 14 191 3 34 Delicious Starkspur Significance either OF ALAR AND GIBBERELLIC ACID ON THICKNESS TISSUES OF STARKSPUR AND GOLDEN DELICIOUS* Level 0.4403 0.2.187 0.6475 0.8584 Total Number o f Palisade Layer 0.1668 There was no s i g n i f i c a n t e f f e c t of any o f these t r e a t m e n t s on l e a f t i s s u e s cultivar. 0.9695 thickness of Average Pa l i s a d e C e l l Length 0.4339 TABLE 17 INFLUENCE Treatment (ppm) OF ALAR AND GIBBERELLIC ACID ON MEAN SHOOT OF STARKSPUR AND GOLDEN DELICIOUS (CM) 1 X 2 Weeks A f t e r Treatment 3 4 GROWTH 5 6 Control 23h 31g 33fg 35cdefg 38cdef 40cd A l a r - 1000 24h 34efg 38cdef 39cdef 39cdef 41c GA 23h 34efg 41c 48b 56a 58a 19 h 32g 35defg 38cdef 40cd 41c - 1000 A l a r - 1000, GA - 1000 S i g n i f i c a n c e L e v e l of I n t e r a c t i o n 0.0001 means h a v i n g a l e t t e r i n common a r e not s i g n i f i c a n t l y 5 per cent l e v e l by Duncan's M u l t i p l e Range T e s t . different a t the DISCUSSION S t a r k s p u r was found to have a t h i c k e r l e a f , p a l i s a d e parenchyma and a g r e a t e r mean p a l i s a d e number and tivars. Arasu s i z e than the other three These r e s u l t s agree w i t h the c o n c l u s i o n s of Westwood (1) and Westwood and Z i e l i n s k i have t h i c k e r l e a v e s and (38) palisade tissue. have s h o r t e r i n t e r n o d e s , g r e a t e r l e a f t h a t the spurtype They a l s o found cul- (37), mutants the mutant to s u r f a c e per f o o t of shoot, fewer 2 s i d e branches but more spurs, and of l e a f . g r e a t e r c h l o r o p h y l l content These a t t r i b u t e s of spurtypes l i g h t d i s t r i b u t i o n , bearing fruit-bearing potential. t h i c k e r l e a f and examination f a v o r them w i t h r e g a r d surface, photosynthetic e f f i c i e n c y The present study has demonstrated of the l e a f anatomy of the spurtype mutants. i n t h i c k n e s s of the p a l i s a d e parenchyma was t h i s d i f f e r e n c e was By due both increase longer The Star- t h i c k e r than those of Red D e l i c i o u s a t t r i b u t e d to t h i c k e r p a l i s a d e parenchyma. comparing the t h i c k n e s s of l e a f t i s s u e s of Red cent t h i c k e r i n terms of t o t a l l e a f t h i c k n e s s . Delicious with Apparently s i g n i f i c a n t d i f f e r e n c e s i n t h i c k n e s s of lower e p i d e r m i s , dermis and and to Golden D e l i c i o u s ( T a b l e 2), i t i s e v i d e n t t h a t the l a t t e r was no to careful The a g r e a t e r mean p a l i s a d e l a y e r o f them. krimson l e a v e s were o n l y s l i g h t l y and found cm the p a l i s a d e t i s s u e s of the spurtype mutants by p a l i s a d e c e l l s and per spongy parenchyma between these two varieties. 11.3 per t h e r e were upper e p i The dif- f e r e n c e i n t o t a l l e a f t h i c k n e s s i s a t t r i b u t a b l e to d i f f e r e n c e s i n p a l i sade parenchyma which was 18 per cent t h i c k e r i n Golden D e l i c i o u s than 49 i n Red Delicious. 18 per cent h i g h e r Looney r e p o r t e d t h a t Golden D e l i c i o u s had net a s s i m i l a t i o n r a t e than Red an Delicious (22). Compact mutants have been r e p o r t e d to have a t h i c k e r stem and shorter internodes study i t was than s t a n d a r d v a r i e t i e s vars studied (Table 4 ) . tex, p i t h and p i t h c e l l s among the f o u r cell culti- I n stem c r o s s s e c t i o n s , the ..thickness of c o r - t o t a l stem of mutants were a l s o not d i f f e r e n t from (Table 5). types were not d i f f e r e n t from the spur These r e s u l t s r e p r e s e n t types the Furthermore, i n c e l l diameter of d i f f e r e n t t i s s u e s ( T a b l e 6 ) , standard standard However, i n t h i s found t h a t t h e r e were no s i g n i f i c a n t d i f f e r e n c e s i n l e n g t h of collenchyma, parenchyma and standard (37, 38). types. the f i r s t comparisons between compact w i t h r e s p e c t to stem anatomy. used i n t h i s experiment was Since and the shoot m a t e r i a l taken from the f i r s t i n t e r n o d e under the growing t i p , m a n i f e s t a t i o n of the reasons f o r the r e p o r t e d t h i c k e r and s h o r t e r shoots may should not occur i n t h i s r e g i o n of the shoot. c o n s i d e r mature t i s s u e s . F u t u r e work I t i s q u i t e p o s s i b l e t h a t the of A l a r treatment have not shown up completely effects on t h i s premature t i s - sue . In experiment I I , Red not show any with ppm 12). However, i n experiment I I I , A l a r a t found to i n c r e a s e the t h i c k n e s s of t o t a l chyma and ppm did s i g n i f i c a n t d i f f e r e n c e i n l e a f t h i c k n e s s when compared the c o n t r o l ( T a b l e was D e l i c i o u s t r e a t e d w i t h A l a r a t 1000 l e n g t h of p a l i s a d e c e l l s r e s u l t s might be due (Table 15). 1000 l e a f , spongy parenThese c o n f l i c t i n g to the d i f f e r e n c e s of season, l o c a t i o n and s p e c i f i c e f f e c t of the m a t e r i a l used i n the experiment. the These a r e the 50 first r e s u l t s reported on the e f f e c t s of A l a r on the anatomy of e i t h e r compact or s t a n d a r d Red Delicious. I n Golden D e l i c i o u s thinner (Table lower epidermis and spur Golden D e l i c i o u s had leaf thickness, and 12), the fewer p a l i s a d e thinner The c e l l s and cells. luence the e f f e c t of A l a r t r e a t m e n t . (17) total infthat differently concentration. p r e s e n t study a l s o r e v e a l e d t h a t s u p p r e s s i o n of I t was terminal found t h a t of f o u r c u l t i v a r s used i n experiment I I , S t a r k r i m s o n t r e e s were not a f f e c t e d by A l a r treatment ( T a b l e most s u s c e p t i b l e to the A l a r 7, F i g . 7) and treatment ( T a b l e among c u l t i v a r s , the above r e s u l t s l a b e l e d m a t e r i a l had c o u l d be than the Golden D e l i c i o u s cent ( T a b l e GA stimulated GA was applied treatment. ( 1 6 ) , and Golden D e l i c i o u s A l a r a t 19 per explained differences i f incorrectly However, even b e f o r e the app- treatment much d i f f e r e n t l y l e a f number, l e n g t h or w i d t h of Red w i t h those o f H a l f a c r e Besides the trees. krimson were a f f e c t e d by A l a r by 10). sampled grew v e r y v i g o r o u s l y l i c a t i o n of A l a r , they responded to the Neither S t a r k s p u r was been used i n the experiment. though the S t a r k s p u r t r e e s r Stark- a l s o reported responded to A l a r growth by A l a r v a r i e d among the c u l t i v a r s used. the had the t r e a t e d Thus c u l t i v a r might Halfacre York I m p e r i a l when t r e a t e d a t the same of t r e a t e d p l a n t s spongy parenchyma, a s m a l l e r fewer p a l i s a d e the Golden D e l i c i o u s and leaves 1000 11), but ppm no the was D e l i c i o u s and Star- These f i n d i n g s do not f i n d i n g s need v e r i f i c a t i o n . found to reduce the e f f e c t was observed on shoot growth of Golden D e l i c i o u s and agree In l e a f number Starkspur. S t a r k s p u r but when i n combination w i t h A l a r , the s t i m u l a t i n g e f f e c t was 51 cancelled c o m p l e t e l y by A l a r . E d g e r t o n and t h a t the s t i m u l a t i n g e f f e c t of GA be c a n c e l l e d by on Red Hoffman (14) also found D e l i c i o u s apple trees could Alar. S i n c e the n a t u r a l compact mutants have many m e r i t s over the dard growing s t r a i n s , i t may be d e s i r a b l e to induce s i m i l a r changes i n s t a n d a r d a p p l e t r e e s or i n t e n s i f y the d e s i r a b l e t r a i t s by means of treatment w i t h growth r e g u l a t o r s there a r e o n l y a few workers s t u d y i n g n a t u r a l compact mutants and worker, I n t r i e r i (19), spur type t r e e s r a n d larities 9.5 per c e n t . parenchyma. active s i t e within dant. dings h e l p due of p a l i s a d e increase of s e v e r a l c u l t i v a r s had growth r a t e of Red immediate and weeks a f t e r the a p p l i c a t i o n of A l a r . of H a r r o l d Red ppm and 4000 ppm, the a noted. e x p l a i n the r e p o r t of E d g e r t o n and 1000 that Delicious i n t o t a l thickness to an parenchyma was i n h i b i t o r y e f f e c t was t r a t i o n s of Red of i n thickness l e a f t i s s u e which responds to the A l a r i n h i b i t e d the This increase of H a r r o l d Hence i t seems t h a t t h i s t i s s u e i s the the t r e a t e d a p p l e trees literature, One t r e a t e d w i t h A l a r showed many s i m i - A f t e r the treatment w i t h A l a r 4000 ppm, i n thickness However, induced compact h a b i t . leaf thickness A p p a r e n t l y the t i s s u e a f t e r A l a r treatment was palisade compacts anatomy. A l a r treatment i n c r e a s e d by such as A l a r . upon r e v i e w i n g the standard trees of the the r e l a t i o n s h i p s among the the c h e m i c a l l y reported, i n morphology and stan- leaf of primary growth r e t a r - 16 per cent increase These a n a t o m i c a l Hoffman (14) thicker the fin- that A l a r leaves. Delicious apple shoots. l a s t e d f o r more than s i x When A l a r was a p p l i e d a t concen- i n h i b i t i o n s of the shoot growth D e l i c i o u s were found to be 18 per cent and 27 per cent 52 respectively. This ( 3 , 4, 16, 14, 15, r e s u l t concurs w i t h the f i n d i n g s of o t h e r 17) that A l a r i n h i b i t s the t e r m i n a l workers growth of I n t e r e s t i n g l y , A l a r d i d not appear to i n f l u e n c e the l e n g t h of any the stem c e l l types examined i n the c u r r e n t As e a r l i e r , t h i s may have been due study. support the f i n d i n g s of M a r t i n jit a l . (24) who had a greater of discussed to the sampling procedure but may apples. i t also found t h a t A l a r e f f e c t on c e l l d i v i s i o n i n a p p l e f r u i t s than on cell size. U n t r e a t e d H a r r o l d Red continuously. D e l i c i o u s shoots have a tendency to grow T h i s would r e s u l t i n a t a l l e r S t a r k r i m s o n and A l a r t r e a t e d H a r r o l d curves a r e q u i t e s i m i l a r and These r e s u l t s a r e cluded study has considering review of I n t r i e r i (19) who the c o n c e n t r a t i o n spur type t r e e s to the u n d e r s t a n d i n g of A p p a r e n t l y both the nature of of A l a r a r e the use of t h i s growth con- anatomy. contributed e f f e c t s of A l a r on a p p l e t r e e s . c u l t i v a r and D e l i c i o u s the shoot growth a p p l e t r e e s t r e a t e d w i t h A l a r and a r e q u i t e s i m i l a r i n morphology and present However, i n the become l e v e l a t about the f o u r t h week. consistent withtthe t h a t standard This Red tree. the the important f a c t o r s when retardant. SUMMARY A two and y e a r study was conducted to i n v e s t i g a t e a n a t o m i c a l changes i n a p p l e l e a f and shoot There i s no p r e v i o u s a n a t o m i c a l comparisons of compact a p p l e t r e e s or between A l a r t r e e s of Red Delicious. and t r e a t e d Red numbers of p a l i s a d e two and the ppm From A p r i l was shoot stems between applied reported. D e l i c i o u s and Golden D e l i c i o u s , A l a r were a p p l i e d experiment A l a r a t the c o n c e n t r a t i o n s of 0, to c u l t i v a r s which had 1000 each treatments. c o n c e n t r a t i o n s of to a d d i t i o n a l t r e e s of the to June 1969, untreated spongy parenchyma compact t y p e s , were s t u d i e d without A l a r second phase of the 1000 ana- l a y e r s i n compact mutants or i n A l a r first v a r i e t i e s , Red w i t h s t a n d a r d and I n the width, t r e a t e d and D e t a i l e d measurements of D e l i c i o u s are I n 1968, and Factors length. s t a n d a r d and thickness morphological stem t i s s u e s . l y z e d were l e a f anatomy, l e a f number, l e a f l e n g t h anatomy and the 0 same c u l t i v a r s . and been g r a f t e d 4000 ppm on EM II of root- stocks . Without A l a r treatment, i t was l e a f and thicker palisade s t u d i e d and Red mutants had greater The shorter parenchyma than the o t h e r t h r e e D e l i c i o u s was than Golden D e l i c i o u s . found t h a t S t a r k s p u r had Results thickness a l s o i n d i c a t e d t h a t compact a p p l e palisade parenchyma number as compared w i t h standard compact mutants have been r e p o r t e d internode. thicker cultivars found to have l e s s t o t a l l e a f on average t h i c k e r l e a v e s and mean p a l i s a d e a types. to have t h i c k e r However, m i c r o s c o p i c e x a m i n a t i o n of and stems and samples taken 54 from the f i r s t internode differences i n c e l l under the growing t i p r e v e a l e d no l e n g t h of collenchyma, parenchyma, p i t h c e l l diameter or t h i c k n e s s The vars. suppression The significant i n the same t i s s u e s . of t e r m i n a l growth by A l a r varied.among response to A l a r was h i b i t i o n of shoot growth by 50 greatest with Starkspur per cells, cent was not a f f e c t e d by A l a r treatment i n the observed. culti- where an i n Starkrimson was same experiment. I n the t h i r d phase of the experiment, A l a r t r e a t e d l e a f b l a d e s p l a n t s were found to i n c r e a s e i n t o t a l t h i c k n e s s , i n t h i c k n e s s spongy parenchyma and from two concentration to d i f f e r i n the l e n g t h of p a l i s a d e c e l l s . of A l a r , i . e . 1000 from each o t h e r . These data and 4000 ppm, i n d i c a t e t h a t the The of of results were not found s i t e which i s most a f f e c t e d by A l a r i s i n the p a l i s a d e parenchyma c e l l s of the leaf tissue. GA by stimulated 29 per c e n t , but the shoot growth of Golden D e l i c i o u s and t h i s s t i m u l a t i n g e f f e c t was Starkspur prevented by A l a r . BIBLIOGRAPHY 1. A r a s u , N. T. 1968. Spur-Type s p o r t s i n A p p l e s . M a i l i n g Res. S t n . f o r 1967. 113-119. Ann. Rept. E . 2. Ashby, D. L . and N. E . Looney. 1968. M i n e r a l content o f f r u i t and leaves o f S p a r t a n a p p l e t r e e s t r e a t e d w i t h s u c c i n i c a c i d 2,2-Dimethyl H y d r a z i d e . Can. J . P l a n t S c i . 48:422-423. 3. Barden, J . A. 1968. E f f e c t s of A l a r on the growth and d i s t r i b u t i o n of the growth increment i n one y e a r o l d a p p l e t r e e s . P r o c . Amer. Soc. H o r t . S c i . 93:33-39. 4. B a t j e r , L. P., M. W. W i l l i a m s and George C. M a r t i n . 1964. E f f e c t s o f N-dimethyl amino s u c c i n a m i c a c i d (B-nine) on v e g e t a t i v e and f r u i t c h a r a c t e r i s t i c s of a p p l e s , p e a r s , and sweet c h e r r i e s . P r o c . Amer. Soc. H o r t . S c i . 85:11-16. and M. W. W i l l i a m s . 1966. E f f e c t s of N-dimethyl amino s u c c i n a m i c a c i d ( A l a r ) on watercore and h a r v e s t drop o f a p p l e s . P r o c . Amer. Soc. H o r t . S c i . 77:76-79. Beakbane, A. B. 1964-1965. Some e f f e c t s of g i b b e r e l l i n on the anatomy o f a p p l e l e a f d i s c s . Ann. Rept. E . M a i l i n g Res. S t n . f o r 1964. 102-103. . 1967. A r e l a t i o n s h i p between l e a f s t r u c t u r e and growth p o t e n t i a l i n a p p l e . Ann. A p p l . B i o l . 60:67-76. 8. B l a n p i e d , G. D., R. M. Smock and D. A. K o l l a s . 1967. E f f e c t of A l a r on optimum h a r v e s t dates and keeping q u a l i t y o f a p p l e s . P r o c . Amer. S o c . H o r t . S c i . 90:467-474. 9. Brooks, H. J . 1964. Responses o f pear s e e d l i n g s to N-dimethylaminosuccinamic a c i d , a growth r e t a r d a n t . Nature 203:1303. 10. Bukovac, J . J . 1964. M o d i f i c a t i o n of the v e g e t a t i v e development of Phaseolus v u l g a r i s w i t h N,N-dimethyl aminomaleamic a c i d . Amer. J . B o t . 51:480-485. 11. Cathey, H. M. Ann. Rev. 12. C l e l a n d , R. 1965. E v i d e n c e on the s i t e of a c t i o n of growth r e t a r d a n t s . P I . and C e l l Phys. 6:7-15. 13. Dahlgren, G. and N. L . Simmerman. 1963. Intramolecular catalys i s of the h y d r o l y s i s of N-dimethylaminomaleamic a c i d . S c i . 140:484-486. 1964. P h y s i o l o g y of growth r e t a r d i n g c h e m i c a l s . P I . Phys. 15:271-302. 56 14. Edgerton, L . J . and M. B. Hoffman. 1965. Some p h y s i o l o g i c a l responses o f a p p l e t o N-dimethylamino succinamic a c i d and o t h e r growth r e g u l a t o r s . Proc. Amer. Soc. H o r t . S c i . 86:28-36. 15. F i s h e r , D. V. and N. E. Looney. 1967. Growth, f r u i t i n g and s t o rage response o f f i v e c u l t i v a r s of b e a r i n g a p p l e t r e e s t o Ndimethylamino succinamic a c i d ( A l a r ) . Proc. Amer. Soc. H o r t . Sci. 90V9-19. 16. H a l f a c r e , R. G. and J . A. Barden. 1968. A n a t o m i c a l responses o f a p p l e l e a f and stem t i s s u e s t o s u c c i n i c a c i d 2,2-dimethylhydr a z i d e ( A l a r ) . Proc. Amer. Soc. H o r t . S c i . 93:25-32. 17. r_ 18. Haupt, A. W. 1930. A g e l a t i n f i x a t i v e f o r p a r a f f i n S t a i n Technol. 5:97-98. 19. I n t r i e r i , C. 1967. Comparaison e n t r e l e s types "Spur" e t l e s a r b r e s t r a i t e s par l e s " r e t a r d a n t s ' d e c r o i s s a n c e . " La Pomol o g i e F r a n c a i s e . 9:151-2, 155-6. 20. Johansen, D. A. 1940. P l a n t M i c r o t e c h n i q u e . Co., I n c . New York. 21. Looney, N. E. 1967. E f f e c t o f N-dimethylamino succinamic a c i d on r i p e n i n g and r e s p i r a t i o n of a p p l e f r u i t s . Can. J . P l a n t Sci. 47:549-553. , J . A. Barden and H. A. R o l l i n s . 1968. E f f e c t s of A l a r on morphology, c h l o r o p h y l l c o n t e n t , and n e t CC>2 a s s i m i l a t i o n r a t e o f young a p p l e t r e e s . Proc. Amer. Soc. H o r t . S c i . 93:40-52. sections. McGraw-Hill Book 22. . 1968. Comparison of p h o t o s y n t h e t i c e f f i c i e n c y o f two a p p l e c u l t i v a r s w i t h t h e i r compact mutants. Proc. Amer. Soc. H o r t . S c i . 92:34-36'. 23. . 1968. I n h i b i t i o n o f a p p l e r i p e n i n g by s u c c i n i c a c i d , 2,2-dimethyl h y d r a z i d e and i t s r e v e r s a l by e t h y l e n e . P I . Phys. 43:1133-1137. 24. . 19 69. R e g u l a t i o n o f sweet c h e r r y m a t u r i t y w i t h s u c c i n i c a c i d 2,2-dimethyl h y d r a z i d e ( A l a r ) and 2-chloroethanephosp h o r i c a c i d ( E t h r e l ) . Can. J . P l a n t S c i . 49:625-627. 25. M a r t i n , D., T. L . Lewis and J . Cerny. 1968. The e f f e c t o f A l a r on f r u i t c e l l d i v i s i o n and o t h e r c h a r a c t e r i s t i c s i n a p p l e s . Proc. Amer. Soc. H o r t . S c i . 92:67-70. 57 26. M a r t i n , G. C., M. W. W i l l i a m s and L. P. B a t j e r . 19.64. Movement and f a t e of l a b e l e d N-dimethylamino succinamic a c i d (B-Nine), a s i z e c o n t r o l l i n g compound, i n apple s e e d l i n g s . Proc. Amer. Soc. H o r t . S c i . 84:7-13. 27. McClendon, J . H. 1962. The r e l a t i o n s h i p between the t h i c k n e s s of deciduous l e a v e s and t h e i r maximum p h o t o s y n t h e t i c r a t e . Amer. J . B o t . 49:320-322. 28. M i t c h e l l , J . W., J . W. W i r w i l l e and L. W e i l . 1949. P l a n t growthr e g u l a t i n g p r o p e r t i e s of some n i c o t i n i u m compounds. Science 110:252-254. 29. Moore, T.C. 1967. K i n e t i c s of growth r e t a r d a n t and hormone i n t e r a c t i o n s i n a f f e c t i n g cucumber h y p o c o t y l e l o n g a t i o n . Phys. 42: 677-684-. .30. PI. P r e s t o n , W. H., J r . and C. B. L i n k . 1958. Use of 2 , 4 - d i c h l o r o b e n z y l t r i b u t y l p h o s p h o n i u m c h l o r i d e to dwarf p l a n t s . P I . Phys. Suppl. 33. 31. Reed, D. J . , T. C. Moore and J . D. Anderson. 1965. P l a n t growth r e t a r d a n t B-995: A p o s s i b l e mode of a c t i o n . Science 148:1469-1471. 32. R i d d e l l , J . A., H. A. Hageman., C. M. J'Anthony and W. L. Hubbard. 1962. R e t a r d a t i o n of p l a n t growth by a new group o f c h e m i c a l s . Science. 136*391. 33. Ryugo, K. 1966. P e r s i s t e n c e and m o b i l i t y of A l a r (B-995) and i t s e f f e c t on a n t h o c y a n i n metabolism i n sweet c h e r r i e s , Prunus avium. P r o c . Amer. Sod. H o r t . S c i . 88:160-166. 34. Sachs, R. M. , C. F. B r e t z and A. Lang. 1956. Shoot h i s t o g e n e s i s : ; . The e a r l y e f f e c t of g i b b e r e l l i n upon stem e l o n g a t i o n i n two r o s e t t e p l a n t s . Amer. J . B o t . 46:376-384. 35. and M. A. Wholers. 1964. I n h i b i t i o n of c e l l p r o l i f e r a t i o n and expansion i n v i t r o by t h r e e stem growth r e t a r d a n t s . Amer. J . B o t . 51:44-48. 36. T o l b e r t , N. E. 1960. ( 2 - c h l o r o e t h y l ) trimethylammonium c h l o r i d e and r e l a t e d compounds as p l a n t growth substances. J. Biol. Chem. 235:475-479. 37. Westwood, M. N. 1963. Some d i f f e r e n c e s i n growth, chemical comp o s i t i o n and m a t u r i t y between a spur mutant and standard growing D e l i c i o u s a p p l e . Proc. 59th Ann. Meeting Wash. H o r t . 58 Assoc. 38. Dec. 2, 3, 4. Wenatehee, Wash. and Q. B. Z i e l i n s k i . 19 66. Comparative growth h a b i t and l e a f c o m p o s i t i o n of a compact mutant and standard D e l i c i o u s apple. Proc. Amer. Soc. H o r t . S c i . 88:9-13. 39. W i r w i l l e , J . W. and J . W. M i t c h e l l . i n h i b i t i n g compounds. Bot. Gaz. 1950. S i x new 111:491-494. plant-growth- 40. Z e e v a a r t , J . A. D. 1966. I n h i b i t i o n of stem growth and f l o w e r f o r m a t i o n i n P h a r b i t i s n i l w i t h N, N-dimethylaminosuccinamic a c i d (B-995). Planta (Berl.) 71:68-80. 59 APPENDIX A n a l y s i s o f V a r i a n c e Models (Table numbers correspond t o those i n t e x t ) Table 1 Line Number Line number of F denominator Degrees o f freedom Source o f V a r i a t i o n Expected mean squares Clone (c-1) = 3 T r e e s w i t h i n Clones c(t-l) = 8 Shoots w i t h i n Trees ct(s-l) = 12 Leaves w i t h i n Shoots cts(e-l) = 2<4 5 Position p-1 = 2 6 P o s i t i o n x Clone (p-D(c-l) = 6 7 P o s i t i o n x Trees w i t h i n Clones c(p-lHt-l) = 16 0 8 P o s i t i o n x Shoots w i t h i n Trees ct(p-lXs-l) = 24 0 9 P o s i t i o n x Leaves w i t h i n Shoots cts(p-l)(l-l)= Disc ctspl(d-l) = 144 ctspld(m-l) = 864 ctspldm-1 =1151 10 E Measurements Total w i t h i n Discs 48 o 2 E + 2 o 2 ° E 2 0 10 0 0 + 2 a 2 2 E 2 E 2 E + 2 + 2 + 2 2 ° E 2 E +1 2 o 2 + 1 2 a 2 S(TC) S(TC) + 2 l + 1 2 + 2 4 o 2 T(C) + 7 2 e 2 C * T(C) o 2 2 ° S(TC) 2 2 ° D ( T C S L P ) ° L(TCS) +6 2 2 2 2 ° D(TCSLP) ° PL(TCS) * PS(TC) ° T P ( C ) +2 + 2 + 2 2 + 6 2 0 +6 D(TCSLP) 2 E 2 D(TCSLP) ° L(TCS) 2 E ° L(TCS) + 6 2 2 ° D(TCSLP) ° L(TCS) 2 10 D(TCSLP) + 2o 2 ° D(TCSLP) ' +1 PL(TCS) a +4o ,+l(o PL(TCS) + 8 PS(TC) + 8a PS(TC) + 8o 2 2 2 ° D ( T C S L P ) ° P L ( T C S ) ° PS(TC) + 2 +2 2 2 ° D ( T C S L P ) ° PCLCTCS) +2 2 + 2 + 4 D(TCSLP) + 9 6 6 2 P. .•24o' TP(C) PC TP(C) 60 Table 2, 3 Line Number Source o f V a r i a t i o n Line number of F denominator Degrees o f freedom 1 Variety (v-1) = 1 2 Type (t-1) = 1 3 V a r i e t y x Type (v-D(t-l) = 1 4 Tree w i t h V a r i e t y and Type vt(r-l) = 8 E Measurements w i t h Type vtr(m-l) =1140 vtrm-1 = 1151 Total Variety, Expected mean squares E o 2 + 9 6 ° R(VT) 2 ° E 2 + 9 6 ( j 2 R(VT) ° E + 9 6 < j 2 R(VT) ° E + 9 6 2 2 + 5 7 + 2 8 8 ° R(VT) 2 + 5 7 6 6 2 6 e 2 V T ° VT 2 61 T a b l e U, 6 Line Number Line number of F denominator Degrees o f freedom Source o f V a r i a t i o n Expected mean squares (v-1) = 3 v(t-l) = 8 a 2 E + 5 o 2 C(VTS) Shoot w i t h i n Tree vt(s-l) = 12 a 2 E + 5 a 2 C(VTS) Section within vts(c-l) = 24 a vtsc(m-l) = 192 vtscm-1 = 239 Variety Tree w i t h i n Variety Shoot Measurements w i t h i n Total Shoot ° E 2 + 5 o 2 C(VTS) + 1 0 o 2 + 1 0 V ° C<VTS) 5 2 + 1 0 o 2 S(VT) S(VT) ° S(VT) 2 + 2 0 + 2 0 o 2 T(V) ° T(V) 2 + 6 0 e 2 V Table 5, 9 Line number of F denominator Line Number 1 2 Expected mean s q u a r e s Source o f V a r i a t i o n 2 0 3 0 E 0 Variety Tree w i t h i n Variety 3 Shoot w i t h i n Tree E Measurements w i t h i n Total Shoot V 3 o 2 2 E 2 E S(VT) + 6 ° T(V) 2 + + 3 ° 2 2 S ( V T ) ° T(V) + 3 ° 2 S(VT> + 6 1 8 9 2 V 63 Table 7, 8, 10, 11 Line Number 1 2 3 4 E . Line number of F denominator Degrees o f freedom Expected mean squares Source o f V a r i a t i o n (t-1) = 1 2 E t(s-l) =10 E ° E (d-1) = 7 E c 2 (d-D(t-l) = 7 E a 2 t(d-lMs-l) = 70 o 2 tds-1 = 95 a 2 + 8 ° S(T) + 8 ° S(T) 2 Treatment Shoot w i t h i n 2 2 Treatment +126 E 2 D Date E Date x Treatment Date x Shoot Total E +12a 2 D T + 4 8 6 2 T 64 T a b l e 12 Line Number Source o f V a r i a t i o n Treatment (t-1) Shoot w i t h i n Treatment t(s-l) Leaf w i t h i n Shoot ts(l-l) Disc within Leaf Section within Disc Measurements w i t h i n Total Section Line number of F denominator Degrees o f freedom Expected mean squares 2 o 2 E + 2 ° C(TSLD) 3 a 2 E + 2 ° C(TSLD) 10 4 tsl(d-l) = 100 5 0 tsld(c-l) = 120 E 0 tsldc(m-l) -240 tsldcm-1 :479 ° E 2 2 E 2 E 0 + 2 2 + 2 o 2 2 + 2 2 E a ° + 4 o 2 + 4 o 2 C(TSLD) + 4 o 2 D(TSL) D(TSL) D(TSL) 2 2 C ( T S L D ) ° D(TSL) + 4 2 C(TSLD) + 2 4 o 2 + 2 4 o 2 + 2 4 L(TS) L(TS) + 4 8 o 2 ° L(TS) 2 + 4 8 o 2 S(T) S(T> + 2 1 , 6 2 T T a b l e 13 Line Number Source o f V a r i a t i o n Treatment Shoot w i t h i n (t-1) Treatment Section within Shoot Measurements w i t h i n Total Line number of F denominator Degrees o f freedom Section Expected mean squares a s(t-l) V ° C(TS) 5 ° E + 5 o 2 ° E + 5 2 st(c-l) 10 stc(m-l) 80 stcm-1 99 2 2 +1 0 a 2 C(TS) ° C(TS) 2 + 1 0 S(T) +5 0 8 ° S(T) 2 2 T 66 Table 14 Line Number Source o f V a r i a t i o n Treatments Tree w i t h i n Treatment Line number of F denominator Degrees of freedom (t-1) = 3 t(r-l) = 16 Leaf w i t h i n Tree tr(l-l) D i s c w i t h i n Leaf trl(d-l) = "»0 Section within trld(c-l) = 80 trldc(m-l) = 160 trldcm-1 = 319 Disc Measurement w i t h i n Total Section 20 = Expected mean squares 2 2 E 0 + 2 ° 4.1 2 S(TRLD) 2 E+"2 " o o S(TRLD) ° + 4 r 2 2 E a + 2 ° 2 S(TRLD) ° + 4 . 2 E S(TRLD) 2.-2 ° E S(TRLD) 0 + 4 a h 0 2 2 D(TRL) ° L(TR) + 8 + 1 6 ° 2 R(T) , + 8o + 16o' D(TRL)* L(TR) R(T) o u 2 2 D ( T R L ) ° L(TR) + 8 2 D(TRL) 2 + 8 0 6 T 67 T a b l e 15 Line Number Source o f V a r i a t i o n Treatment Tree w i t h i n (t-1) Treatment Line number of F denominator Degrees o f freedom t(r-l) 3 2 a 24 E 2 ° E 5 E 2 « E Date d-1 Date x Treatment (d-l)(t-l) = t(d-l)(r-l) = 120 tdr-1 = 167 Date x T r e e w i t h i n Total Treatment Expected mean squares 15 V 6 < j 2 + 6 R(T) 2 ° R(T) + 2 8 2 ° D 2 2 a +7o E D T + 4 2 9 2 T 68 T a b l e 16 Line Number Source o f V a r i a t i o n L i n e number of F denominator Degrees o f freedom Expected mean squares Block (r-l) = 1 Variety (v-1) = 1 Treatment (t-1) = 3 0 V a r i e t y x Treatment (v-lXt-1) = 3 0 B l a c k x V a r i e t y and Treatment (r-D(vt-l) = 7 Leaf w i t h i n vtr(l-l) = 16 0 vtrl(p-l) = 32 0 Section within Position vtrlp(s-l) = 64 0 Measurement w i t h i n vtrlps(m-l) = 128 vtrlpsm-1 255 Treatment Position within Total Leaf Section = ° E 2 + 2 c 2 2 0 E 2 E + 2 a ° + 2 2 E + 2 a S ( V T R L P ) '* p(VTRL) ' L ( V T R ) + E + 2 a 2 E + 2 ° E + 2 ° 2 +8( 2 + 1 2 8 o 2 2 2 2 S(VTRLP) "° P ( V T R L ) ° L ( V T R ) + + 8 2 S(VTRLP) 2 2 P(VTRL) ° L(VTR) +l t a +8 + S(VTRLP) v + 8 + 4 a ° P(VTRL) + 8o u + 8 2 2 S(VTRLP)* * P(VTRL) 1 2 S(VTRLP) 0 + 1 2 8 8 2 V T + 1 5 ° 2 RVT L(VTR)>+16o' RVT 2 2 2 S ( V T R L P ) ° P ( V T R L ) ° L(VTR) + 4 R 2 +6 1 4 8 2 2 2 S(VTRLP) "*° P ( V T R L ) ° L ( V T R ) 2 2 a ,-+2a 2 o2 + 3 2 2 ° VT 69 T a b l e 17 Line Number 1 2 3 H 5 6 7 8 9 E L i n e number of F denominator Degrees o f freedom Expected mean squares Source o f V a r i a t i o n (b-1) = 1 E o +48o 2 (v-1) = 1 E o 2 *U8e 2 E (t-1) = 3 E c 2 +248 2 E (t-D(v-l) = 5 o 2 (b-D(tv-l) = 7 E o .+6o (d-1) = 5 E o .+16e (d-D(v-l) =15 E o 2 (d-lXt-l) =15 E o 2 (d-l)(t-l)(v-l)alS E o 2 2 E B Block v Variety T Treatment 3 E +6o „+12o 2 T B V V a r i e t y x Treatment B l o c k x Treatment, 2 r E + 6 2 ° T B V Variety 2 r E + 1 6 E 2 2 D Date E *8o 2 •to 2 + 2„ +2o 22 + 8 ° 2 D V Date x V a r i e t y E ' ^ D T Date x Treatment E Date x Treatment x V a r i e t y Date x B l o c k w i t h i n Total vt(d-lXb-l) = HO vtdb-1 = 95 Treatment o 2 E 1 0 D T V 2 T V
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Leaf and stem anatomy of several apple cultivars, their compact mutants, and alar treated plants. Liu, Alice Chen-Miao 1970
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Title | Leaf and stem anatomy of several apple cultivars, their compact mutants, and alar treated plants. |
Creator |
Liu, Alice Chen-Miao |
Publisher | University of British Columbia |
Date Issued | 1970 |
Description | Naturally occurring compact (spur type) apple trees (Malus sylvestris L.) were compared with standard and Alar treated trees. Stem anatomy received special attention because no comparisons had been done of the stem anatomy in standard and compact apple trees. Anatomical studies of leaves in compact mutants and in Alar treated Red Delicious are more detailed than in earlier reports. Four cultivars were used in the studies. They were Harrold Red Delicious, a compact mutant of Red Delicious, namely Starkrimson, and standard Golden Delicious, and its compact mutant Starkspur. There were three main studies in this investigation. In the first study, anatomical examinations were made on the four cultivars without Alar treatment. Starkspur Golden Delicious was found to have the thickest leaf and palisade parenchyma among the four cultivars studied. The compact type was found to have a thicker leaf, palisade parenchyma and greater mean palisade number when compared with the standard type. The effect of Alar at concentrations of 0 and 1000 ppm on the same cultivars was investigated in the second study. The suppression of terminal growth by Alar varied among the cultivars. The response to Alar was greatest with Starkspur and 50 per cent inhibition of shoot growth was observed. Starkrimson was not affected by Alar treatment. Microscopic examination revealed that there were no significant differences in cell length of collenchyma, parenchyma and pith cells or in cell diameters and tissue thickness when the samples were taken from the first internode under the growing tip. In study three, the effect of Alar and its interaction with gibberellic acid on Red and Golden Delicious were considered. In this study, comparisons were also made with the untreated compact mutants. Alar treatments of Red Delicious were found to increase thickness of total leaf, spongy parenchyma and the length of palisade cells. The latter two accounted for the increase in total thickness of Alar-treated Red Delicious leaves. Gibberellic acid stimulated the shoot growth of Golden Delicious and Starkspur by 29 per cent, but this stimulating effect was prevented by Alar. |
Subject |
Apples |
Genre |
Thesis/Dissertation |
Type |
Text |
Language | eng |
Date Available | 2011-05-18 |
Provider | Vancouver : University of British Columbia Library |
Rights | For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use. |
DOI | 10.14288/1.0102105 |
URI | http://hdl.handle.net/2429/34650 |
Degree |
Master of Science - MSc |
Program |
Plant Science |
Affiliation |
Land and Food Systems, Faculty of |
Degree Grantor | University of British Columbia |
Campus |
UBCV |
Scholarly Level | Graduate |
Aggregated Source Repository | DSpace |
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