UBC Theses and Dissertations

UBC Theses Logo

UBC Theses and Dissertations

Roles of juvenile hormone in the green peach aphid, myzus persicae sulzer (homoptera: aphididae) Verma, Kulbhushan 1981

Your browser doesn't seem to have a PDF viewer, please download the PDF to view this item.

Notice for Google Chrome users:
If you are having trouble viewing or searching the PDF with Google Chrome, please download it here instead.

Item Metadata

Download

Media
831-UBC_1981_A6_7 V47.pdf [ 8.38MB ]
Metadata
JSON: 831-1.0095157.json
JSON-LD: 831-1.0095157-ld.json
RDF/XML (Pretty): 831-1.0095157-rdf.xml
RDF/JSON: 831-1.0095157-rdf.json
Turtle: 831-1.0095157-turtle.txt
N-Triples: 831-1.0095157-rdf-ntriples.txt
Original Record: 831-1.0095157-source.json
Full Text
831-1.0095157-fulltext.txt
Citation
831-1.0095157.ris

Full Text

ROLES OF JUVENILE HORMONE IN THE GREEN PEACH APHID Myzus p e r s i c a e (Sulzer)(HOMOPTERA: APHIDIDAE) by KULBHUSHAN[VERMA B.Sc. (Hons.) A g r i c , Haryana A g r i c u l t u r a l U n i v e r s i t y ( I n d i a ) , 1978 A THESIS SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE i n FACULTY OF GRADUATE STUDIES THE DEPARTMENT OF PLANT SCIENCE We accept t h i s t h e s i s as conforming to the r e q u i r e d standard THE UNIVERSITY OF BRITISH COLUMBIA January, 1981 Kulbhushan Verma, 1981 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 the 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 study. 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 of t h i s t h e s i s f o r s c h o l a r l y purposes may be granted by the head of my department o r by h i s o r her r e p r e s e n t a t i v e s . I t i s understood t h a t copying or p u b l i c a t i o n 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 allowed without my w r i t t e n p e r m i s s i o n . Department of The U n i v e r s i t y of B r i t i s h Columbia 2075 Wesbrook P l a c e Vancouver, Canada V6T 1W5 Date I o /no \ ABSTRACT The r o l e o f j u v e n i l e hormone (JH) i n a l a t e - a p t e r o u s polymorphism was i n v e s t i g a t e d i n the green peach aphid, Myzus p e r s i c a e . At h i g h e r c o n c e n t r a t i o n s (65 ppm), the j u v e n i l e hormone analogue (JHA), kinoprene, was immediately t o x i c to a p t e r i f o r m nymphs. A t lower c o n c e n t r a t i o n s (10 ppm), the compound was n o n - t o x i c and e x h i b i t e d no apparent m o r p h o l o g i c a l a c t i v i t y i n a p t e r i f o r m stages. In c o n t r a s t , 65 ppm kinoprene a d m i n i s t e r e d t o a l a t i f o r m nymphs had j u v e n i l i z i n g and a p t e r i z i n g e f f e c t s . The extent of these e f f e c t s depended upon when the kinoprene was a p p l i e d . F o u r t h i n s t a r a l a t i f o r m s were the l e a s t s e n s i t i v e as k i n o p r e n e - t r e a t e d nymphs developed i n t o normal a d u l t s w i t h reduced s c l e r o t i z a t i o n and pigmentation. K i n o p r e n e - t r e a t e d t h i r d instars'underwent a supernumerary moult before metamorphosing i n t o a d u l t s with malformed wings. S c l e r o -t i z a t i o n and pigmentation were a l s o l a c k i n g i n these i n s e c t s . When f i r s t and second i n s t a r a l a t i f o r m s i w e r e t r e a t e d w i t h kinoprene, they a l s o underwent a supernumerary moult. The a d u l t s which emerged e x h i b i t e d both l a r v a l and apterous c h a r a c t e r i s t i c s . Wing development was almost t o t a l l y i n h i b i t e d ; the cauda and g e n i t a l p l a t e were p o o r l y developed. In a d d i t i o n , s c l e r o t i z a t i o n and pigmentation were reduced and o c e l l l a c k i n g . The secondary antennal s e n s o r i a were a l s o malformed. These f i n d i n g s c l e a r l y (1) demonstrate t h a t k i n o p r e n e can be employed as a JH mimic t o a l t e r the normal programming o f t h e e p i d e r m a l c e l l s i n a l a t i f o r m nymphs and (2) i n d i c a t e t h a t JH p l a y s an i m p o r t a n t r o l e i n a p h i d morphogenesis and polymorphism. The d i f f e r e n t i a l r e s p o n s e s o f the f o u r a l a t i f o r m nymphal i n s t a r s s u g g e s t t h a t e l e v a t e d JH l e v e l s d u r i n g t h e f i r s t and second i n s t a r s a r e p a r t i c u l a r l y i m p o r t a n t i n i n h i b i t i n g wing development. To d e t e r m i n e t h e p r e n a t a l e f f e c t s o f JH on wing d e v e l o p -ment and morphogenesis, k i n o p r e n e was a l s o a d m i n i s t e r e d t o newly ecdysed a p t e r o u s a d u l t s . Even though c o n d i t i o n s f a v o u r e d a l a t e p r o d u c t i o n , 75% o f t h e o f f s p r i n g produced by k i n o p r e n e -t r e a t e d v i r g i n o p a r a e d e v e l o p e d i n t o normal a p t e r a e . T h i s s u g g e s t s t h a t e l e v a t e d JH t i t e r s i n m a t e r n a l haemolymph i n h i b i t w ing development and promote development o f a p t e r a e . T o p i c a l a p p l i c a t i o n o f t h e a n t i - a l l a t o t r o p i n , p r e c o c e n e - I I , had v a r i a b l e e f f e c t s on a p t e r i f o r m nymphs and a d u l t s . I n a l l s t a g e s , precocene produced a s i g n i f i c a n t d e c l i n e i n l a r v i -p o s i t i o n . The e f f e c t s were more pronounced i n f i r s t and second i n s t a r a p t e r i f o r m nymphs and a p t e r o u s a d u l t s than i n t h i r d and f o u r t h i n s t a r nymphs. When k i n o p r e n e was a p p l i e d t o t h e s e i n s e c t s , l a r v i p o s i t i o n i n c r e a s e d s i g n i f i c a n t l y a f t e r 2 days. The f i n d i n g s demonstrate t h a t JH s t i m u l a t e s r e p r o d u c t i o n i n v i v i p a r o u s morphs o f p e r s i c a e . i i i TABLE OF CONTENTS Page ABSTRACT 1 LIST OF TABLES v LIST OF FIGURES v i i ACKNOWLEDGEMENTS x i INTRODUCTION 1 MATERIALS AND METHODS 1 1 RESULTS 1 7 A. KINOPRENE TREATMENTS 1 7 (a) F i r s t i n s t a r a l a t i f o r m nymphs 1 7 (b) Second i n s t a r a l a t i f o r m nymphs 2 2 (c) T h i r d i n s t a r a l a t i f o r m nymphs 2 5 (d) F o u r t h i n s t a r a l a t i f o r m nymphs 28 (e) A p t e r i f o r m nymphs of apterous a d u l t s 31 (f) A p t e r i f o r m nymphs o f a l a t e a d u l t s 32 (g) Apterous a d u l t s (apterae-producers) 38 (h) Apterous a d u l t s (alate-producers) 45 B. COMBINED EFFECTS OF PRECOCENE AND KINOPRENE 4 5 (a) F i r s t and second i n s t a r a p t e r i f o r m nymphs o f 45 apterous a d u l t s (b) T h i r d and f o u r t h i n s t a r a p t e r i f o r m nymphs of 47 apterous a d u l t s (c) Apterous a d u l t s 51 (d) Apterous nymphs of a l a t e a d u l t s 55 i v Page DISCUSSION 61 A. POLYMORPHISM IN THE GREEN PEACH APHID 61 B. ROLE OF JUVENILE HORMONE 64 (a) Reproduction 65 (b) M o u l t i n g and metamorphosis 68 (c) S c l e r o t i z a t i o n 73 (d) C e p h a l i c sensory organs 74 (e) Wing formation 76 (f) L e t h a l e f f e c t s 80 REFERENCES 81 APPENDIX 87 LIST OF TABLES S e q u e n t i a l l e t h a l e f f e c t s o f 65 ppm kinoprene a p p l i e d to f i r s t i n s t a r a l a t i f o r m nymphs. Developmental e f f e c t s o f kinoprene on s u r v i v i n g f i r s t i n s t a r a l a t i f o r m nymphs. S e q u e n t i a l l e t h a l e f f e c t s o f 65 ppm kinoprene a p p l i e d t o second i n s t a r a l a t i f o r m nymphs. Developmental e f f e c t s of 65 ppm kinoprene on s u r v i v i n g second i n s t a r a l a t i f o r m nymphs. S e q u e n t i a l l e t h a l e f f e c t s o f 65 ppm kinoprene a p p l i e d t o t h i r d i n s t a r a l a t i f o r m nymphs. ' Developmental e f f e c t s o f kinoprene on s u r v i v i n g t h i r d i n s t a r a l a t i f o r m .nymphs. ' ' "v > S e q u e n t i a l l e t h a l e f f e c t s o f 65 ppm kinoprene on f o u r t h i n s t a r a l a t i f o r m nymphs. Developmental e f f e c t s o f kinoprene on s u r v i v i n g f o u r t h i n s t a r a l a t i f o r m nymphs. O v e r a l l e f f e c t o f 10 ppm kinoprene on the f e c u n d i t y o f a p t e r i f o r m nymphs o f apterous a d u l t s up t o 10 days a f t e r a d u l t emergence. O v e r a l l e f f e c t o f 10 ppm kinoprene on the f e c u n d i t y of a p t e r i f o r m nymphs of a l a t e a d u l t s up t o 10 days a f t e r a d u l t emergence. v i Page Table 7. Apterae p r o d u c t i o n by apterous 46 females which were t r e a t e d w i t h 65 ppm kinoprene w i t h i n 12 h r s . of a d u l t emergence. Table 8. E f f e c t s o f t o p i c a l a p p l i c a t i o n 48 of precocene-II on the f e c u n d i t y of a p t e r i f o r m nymphs o f apterous a d u l t s . Except on apterous a d u l t s , kinoprene was a p p l i e d to the p r e c o c e n e - t r e a t e d i n s e c t s f o u r days a f t e r a d u l t emergence. Table 9. E f f e c t s o f t o p i c a l a p p l i c a t i o n 56 of precocene-II on the f e c u n d i t y of a p t e r i f o r m nymphs o f a l a t e a d u l t s . Kinoprene was a p p l i e d to the p r e c o c e n e - t r e a t e d i n s e c t s four days a f t e r a d u l t emergence. r v i i LIST OF FIGURES F i g u r e 1. F i g u r e 2a. c. d. F i g u r e 3a, b. c. d. F i g u r e 4a. C l i p - c a g e s used to c o n f i n e aphids on Chinese cabbage p l a n t . D o r s a l view o f normal a l a t e a d u l t s showing the h e a v i l y s c l e r o t i z e d thorax and d a r k l y pigmented body. D o r s a l view of the head o f normal a l a t e a d u l t showing w e l l - d e v e l o p e d o c e l l i . Secondary antennal s e n s o r i a o f normal a l a t e a d u l t . D o r s a l view of normal apterous a d u l t showing the absence o f s c l e r o t i z a t i o n i n the thorax. D o r s a l view of head of normal apterous a d u l t showing the absence o f o c e l l i . Page 12 20 20 20 20 20 T y p i c a l d e f o r m i t i e s produced i n malformed 21 a l a t e a d u l t o i d s which had been t r e a t e d w i t h kinoprene as f i r s t i n s t a r nymphs. D o r s a l view of thorax showing the e f f e c t 21 on wings and g e n i t a l i a . D o r s a l view of head capsule showing the e f f e c t on o c e l l i . 21 E f f e c t o f kinoprene on secondary antennal 21 s e n s o r i a . D e f o r m i t i e s produced i n malformed a l a t e 24 a d u l t o i d s which had been t r e a t e d with kinoprene as second i n s t a r nymphs. b. M a g n i f i e d view of wing rudiments, 24 c. D o r s a l view of head capsule showing the 24 e f f e c t on o c e l l i . d. E f f e c t o f kinoprene on secondary antennal 24 s e n s o r i a . v i i i Page F i g u r e 5a. D e f o r m i t i e s produced i n malformed 27 a l a t e a d u l t o i d s w h i c h had been t r e a t e d w i t h k i n o p r e n e as t h i r d i n s t a r nymphs. b. M a g n i f i e d v i e w o f b a l l o o n - s h a p e d wings. 27 c. D o r s a l view o f head c a p s u l e showing 27 t h e e f f e c t on o c e l l i . d. E f f e c t o f k i n o p r e n e on secondary 27 a n t e n n a l s e n s o r i a . F i g u r e 6a. V e n t r a l view o f malformed a l a t e a d u l t s 30 w h i c h had been t r e a t e d w i t h k i n o p r e n e as a f o u r t h i n s t a r nymph. b. D o r s a l view o f head c a p s u l e showing the 30 e f f e c t on o c e l l i . c. E f f e c t o f k i n o p r e n e on secondary 30 a n t e n n a l s e n s o r i a . F i g u r e 7. F e c u n d i t y o f normal a p h i d s and t h o s e 34 t r e a t e d w i t h 10 ppm k i n o p r e n e as f i r s t i n s t a r a p t e r i f o r m l a r v a e o f a p t e r o u s a d u l t s . F i g u r e 8. F e c u n d i t y o f normal a p h i d s and t h o s e 35 t r e a t e d w i t h 10 ppm k i n o p r e n e as second i n s t a r a p t e r i f o r m l a r v a e o f a p t e r o u s a d u l t s . F i g u r e 9. F e c u n d i t y o f normal a p h i d s and t h o s e 36 t r e a t e d w i t h 10 ppm k i n o p r e n e as t h i r d i n s t a r a p t e r i f o r m l a r v a e o f a p t e r o u s a d u l t s . F i g u r e 10. F e c u n d i t y o f normal a p h i d s and t h o s e 37 t r e a t e d w i t h 10 ppm k i n o p r e n e as f o u r t h i n s t a r a p t e r i f o r m l a r v a e o f a p t e r o u s a d u l t s . F i g u r e 11. F e c u n d i t y o f normal a p h i d s and t h o s e t r e a t e d w i t h 10 ppm k i n o p r e n e as f i r s t i n s t a r a p t e r i f o r m l a r v a e o f a l a t e a d u l t s . 40 F e c u n d i t y o f normal a p h i d s and t h o s e t r e a t e d w i t h 10 ppm k i n o p r e n e as second i n s t a r a p t e r i f o r m l a r v a e o f a l a t e a d u l t s . F e c u n d i t y o f normal a p h i d s and t h o s e t r e a t e d w i t h 10 ppm k i n o p r e n e as t h i r d i n s t a r a p t e r i f o r m l a r v a e o f a l a t e a d u l t s . F e c u n d i t y o f normal a p h i d s and tho s e t r e a t e d w i t h 10 ppm k i n o p r e n e as f o u r t h i n s t a r a p t e r i f o r m l a r v a e o f a l a t e a d u l t s . F e c u n d i t y o f normal a p h i d s and t h o s e t r e a t e d w i t h 65 ppm k i n o p r e n e as newly-ecdysed a p t e r o u s a d u l t s . F e c u n d i t y o f c o n t r o l a p h i d s and t h o s e ..with 0.5 ug p r e c o c e n e - I I as f i r s t i n s t a r a p t e r i f o r m nymphs o f a p t e r o u s a d u l t s . The e f f e c t s o f 10 ppm k i n o p r e n e a p p l i e d t o pr e c o c e n e -t r e a t e d i n s e c t s f o u r days a f t e r a d u l t emergence a r e a l s o i n d i c a t e d . F e c u n d i t y o f c o n t r o l a p h i d s and t h o s e t r e a t e d w i t h 0.5 ug p r e c o c e n e - I I as second i n s t a r a p t e r i f o r m nymphs o f a p t e r o u s a d u l t s . The e f f e c t s o f 10 ppm k i n o p r e n e a p p l i e d t o p r e c o c e n e -t r e a t e d i n s e c t s f o u r days a f t e r a d u l t emergence a r e a l s o i n d i c a t e d . F e c u n d i t y o f c o n t r o l a p h i d s and t h o s e t r e a t e d w i t h 0.5 ug p r e c o c e n e - I I as t h i r d i n s t a r a p t e r i f o r m nymphs o f a p t e r o u s a d u l t s . The e f f e c t s o f 10 ppm k i n o p r e n e a p p l i e d t o p r e c o c e n e -t r e a t e d i n s e c t s f o u r days a f t e r a d u l t emergence a r e a l s o i n d i c a t e d . F e c u n d i t y o f c o n t r o l a p h i d s and t h o s e t r e a t e d w i t h 0.5 ug p r e c o c e n e - I I as f o u r t h i n s t a r a p t e r i f o r m nymphs o f a p t e r o u s a d u l t s . The e f f e c t s o f 10 ppm k i n o p r e n e a p p l i e d t o prec o c e n e -t r e a t e d i n s e c t s f o u r days a f t e r a d u l t emergence a r e a l s o i n d i c a t e d . F e c u n d i t y o f c o n t r o l a p h i d s and t h o s e t r e a t e d w i t h 0.2 ug p r e c o c e n e - I I as newly-ecdysed a p t e r o u s a d u l t s . The e f f e c t s o f 65 ppm k i n o p r e n e a p p l i e d t o p r e c o c e n e - t r e a t e d i n s e c t s 24 h r s . o r 4 days a f t e r a d u l t emergence a r e a l s o i n d i c a t e d . F e c u n d i t y o f c o n t r o l a p h i d s and t h o s e t r e a t e d w i t h 0.5 ug p r e c o c e n e - I I as f i r s t i n s t a r a p t e r i f o r m nymphs o f a l a t e a d u l t s . The e f f e c t s o f 10 ppm k i n o p r e n e a p p l i e d t o p r e c o c e n e - t r e a t e d i n s e c t s f o u r days a f t e r a d u l t emergence a r e a l s o i n d i c a t e d . F e c u n d i t y o f c o n t r o l a p h i d s and t h o s e t r e a t e d w i t h 0.5 ug p r e c o c e n e - I I as second i n s t a r a p t e r i f o r m nymphs o f a l a t e a d u l t s . The e f f e c t s o f 10 ppm k i n o p r e n e a p p l i e d t o p r e c o c e n e - t r e a t e d i n s e c t s f o u r days a f t e r a d u l t emergence a r e a l s o i n d i c a t e d . F e c u n d i t y o f c o n t r o l a p h i d s and t h o s e t r e a t e d w i t h 0.5 ug p r e c o c e n e - I I as t h i r d i n s t a r a p t e r i f o r m nymphs o f a l a t e a d u l t s . The e f f e c t s o f 10 ppm k i n o p r e n e a p p l i e d t o p r e c o c e n e - t r e a t e d i n s e c t s f o u r days a f t e r a d u l t emergence a r e a l s o i n d i c a t e d . F e c u n d i t y o f c o n t r o l a p h i d s and t h o s e t r e a t e d w i t h 0.5 ug p r e c o c e n e - I I as f o u r t h i n s t a r a p t e r i f o r m nymphs o f a l a t e a d u l t s . The e f f e c t s o f 10 ppm k i n o p r e n e a p p l i e d t o p r e c o c e n e - t r e a t e d i n s e c t s f o u r days a f t e r a d u l t emergence a r e a l s o i n d i c a t e d . x i ACKNOWLEDGEMENTS I s i n c e r e l y thank the f o l l o w i n g persons who c o n t r i b u t e d to the success o f my r e s e a r c h : - My s u p e r v i s o r , Dr. R.H. E l l i o t t f o r h i s u n f a i l i n g h e l p , i n v a l u a b l e i d e a s , and encouragement i n a l l stages o f t h i s work. - Members of my committee, Dr. R.H. E l l i o t t , Dr. A.R. Forbes, Dr. J.H. Myers, and Dr. V.C. Runeckles f o r t h e i r suggestions i n p r e p a r i n g t h i s t h e s i s . - S p e c i a l thanks to Cho-kai Chan and Dr. A.R. Forbes of the A g r i c u l t u r e Canada Research S t a t i o n , Vancouver, f o r p r o v i d i n g aphids and t a k i n g the; e l e c t r o n micrographs. Dr. B.D. F r a z e r p r o v i d e d me w i t h c l i p - c a g e s . - To a l l my l a b . mates, Dale, E l n o r a , Rosemary and Susan who have been very i n t e r e s t i n g and h e l p f u l f r i e n d s . - To my b r o t h e r - i n - l a w , V i j a y , and s i s t e r , Shiksha, f o r t h e i r encouragement and c o - o p e r a t i o n throughout my t h e s i s . - L i s a Walker, f o r her expert t y p i n g and t i m e l y h e l p . 1 INTRODUCTION The green peach aphid, Myzus p e r s i c a e (Sulzer) i s a s e r i o u s a g r i c u l t u r a l p e s t throughout the world ( E s s i g 1926). The s p e c i e s i s polyphagous and has been observed on over 200 host p l a n t s (Forbes p e r s o n a l cortimunication) . The over-w i n t e r i n g eggs are l a i d . o n woody p e r e n n i a l - i n c l u d i n g peach, n e c t a r i n e and o c c a s i o n a l l y a p r i c o t , s w e e t c h e r r y o r plum. Damage t o the w i n t e r host occurs i n the s p r i n g when heavy i n f e s t a t i o n s cause s e r i o u s l e a f damage, w i t h e r i n g and dropping of buds and/or premature f r u i t s e t . These c o n d i t i o n s favour the formation of winged forms which subsequently migrate t o summer host p l a n t s i n c l u d i n g c r u c i f e r s , c u c u r b i t s , tomatoes, l e t t u c e , and a v a r i e t y o f ornamentals. Compared t o oth e r i n s e c t s p e c i e s , the developmental p a t t e r n o f aphids i s ex c e e d i n g l y complex. Depending upon c o n d i t i o n s , the a d u l t female may reproduce s e x u a l l y - \ j . -(oviparous) _6r -p a r t h e n o g e n e t i c a l l y ( v i v i p a r o u s ) (Blackman 1974) . ( In a d d i t i o n , aphids are polymorphic i n t h a t , w i t h i n a s i n g l e s p e c i e s , s e v e r a l d i s t i n c t m o r p h o l o g i c a l forms are produced. These forms, c a l l e d morphs, have d i f f e r e n t r o l e s i n the l i f e c y c l e . Besides the sexual morphs, which occur o n l y i n l a t e f a l l , t h e r e are a l a t e and apterous v i r g i n o p a r a e . The a l a t e v i r g i n o p a r a e do not develop as q u i c k l y as the apterous forms or produce as many o f f s p r i n g (Blackman 19 74; Mackay and W e l l i n g t o n 19 75). However, the a l a t e c o n d i t i o n p r o v i d e s a means o f escape 2 from d e t e r i o r a t i n g f o o d sources,. t h e r e b y e n a b l i n g t h e i n s e c t s t o e s t a b l i s h new c o l o n i e s on f r e s h h o s t p l a n t s . I n s p e c i e s such as p e r s i c a e and t h e cabbage a p h i d , B r e v i c o r y n e b r a s s i c a e * (White 19 68b), t h e a l a t e and a p t e r o u s morphs cannot be d i s t i n g u i s h e d e x t e r n a l l y as f i r s t and second i n s t a r nymphs. However, i n t h i r d and f o u r t h i n s t a r s , p r e s u m p t i v e a l a t e s can be r e c o g n i s e d by s w e l l i n g s on t h e meso- and meta-thorax. Three t h e o r i e s have been advanced t o e x p l a i n wing p o l y -morphism i n a p h i d s . The f i r s t t h e o r y p o s t u l a t e s t h a t t h e winged form i s t h e normal c o n d i t i o n and t h e w i n g l e s s form d e v e l o p s s e c o n d a r i l y . T h i s t h e o r y has been expounded by K l o d n i t s k y (1912), T u r n e r and Baker (1916), Ackerman (1926), Davidson (1927), R i v n a y (1937), and S h u l l (1938). These a u t h o r s have shown h i s t o l o g i c a l l y t h a t wing a n l a g e n s o r r u d i m e n t s a r e p r e s e n t i n a l l embryos and f i r s t i n s t a r nymphs whether t h e y a r e d e s t i n e d t o d e v e l o p i n t o a l a t e s o r a p t e r a e . These f i n d i n g s prompted the a u t h o r s t o suggest t h a t c e r t a i n e n v i r o n m e n t a l and/or p h y s i o l o g i c a l f a c t o r s f a v o u r t h e p r o -d u c t i o n o f t h e a p t e r o u s form by i n h i b i t i n g t h e development o f wing r u d i m e n t s . T h i s h y p o t h e s i s was f u r t h e r s u b s t a n t i a t e d by Johnson and B i r k . (1960) who demonstrated i n A p h i s c r a c c i v o r a t h a t p r i o r t o b i r t h , the wing a n l a g e n s o f p r e s u m p t i v e a p t e r a e were l a r g e r t h a n t h o s e o f . p r e s u m p t i v e a l a t e s . An o p p o s i n g t h e o r y has been proposed w h i c h s u g g e s t s t h a t th e w i n g l e s s form i s t h e normal c o n d i t i o n and t h e winged form d e v e l o p s s e c o n d a r i l y . T h i s t h e o r y was p o s t u l a t e d by White * The taxonomic a u t h o r i t i e s f o r t h i s and o t h e r a p h i d s p e c i e s l i s t e d i n Appendix 6 3 (194 6) who c o u l d n o t d e t e c t any wing a n l a g e n s i n h i s t o l o g i c a l s e c t i o n s o f embryos and young nymphs o f t h e chrysanthemum a p h i d , M a c r o s i p h o n i e l l a s a n b o r n i . A l t h o u g h i t was suggested t h a t t h e w i n g l e s s form was t h e normal c o n d i t i o n , White was unable t o d e t e r m i n e when f o r m a t i o n o f wings began o r what f a c t o r s i n f l u e n c e d t h e i r development. A c c o r d i n g t o t h e t h i r d t h e o r y , t h e p r e s e n c e o r absence o f wing r u d i m e n t s i n embryos may depend upon t h e s t r a i n o f t h e s p e c i e s . T h i s was demonstrated by K i t z m i l l e r (1950) who found wing r u d i m e n t s i n h i s t o l o g i c a l s e c t i o n s o f some chrysanthemum a p h i d s but not i n o t h e r s . A number o f e n v i r o n m e n t a l f a c t o r s have been shown t o i n f l u e n c e wing development i n a p h i d s . Depending upon t h e s p e c i e s and s t a g e o f development, c r o w d i n g appears t o i n f l u e n c e w ing f o r m a t i o n i n a t l e a s t t h r e e d i f f e r e n t ways. E x p e r i m e n t s performed on t h e p o t a t o a p h i d , Macrosiphum e u p h o r b i a e ( S h u l l 192 8 ) ; chrysanthemum a p h i d , M a c r o s i p h o n i e l l a s a n b o r n i ( K i t z m i l l e r 1950); v e t c h a p h i d , Megoura v i c i a e (Lees 1961, 1967); and pea a p h i d , A c y r t h o s i p h o n pisum ( S u t h e r l a n d 1969) have demonstrated t h a t c r o w d i n g d u r i n g t h e a d u l t s t a g e f a v o u r s t h e p r o d u c t i o n o f a l a t e o f f s p r i n g . A p t e r o u s a d u l t s r e a r e d under crowded c o n d i t i o n s , always produced a l a t e o f f s p r i n g whereas t h o s e a d u l t s r e a r e d i n i s o l a t i o n , produced a p t e r o u s ones. I n c o n t r a s t , o t h e r s t u d i e s have s u g g e s t e d t h a t m a t e r n a l c r o w d i n g i s u n i m p o r t a n t b u t t h a t c r o w d i n g d u r i n g e a r l y nymphal s t a g e s has a more pronounced e f f e c t on a l a t e p r o d u c t i o n ( N e i l s 4 1912; S h i n j i 1918; Wadley 1923; R i v n a y 1937; Bonnemaison 1951; Johnson and B i r k 1960; Noda 1961; Toba 1967; D i x o n and G l e n 1971). A p h i d s r e a r e d under crowded c o n d i t i o n s d u r i n g t h e i r f i r s t and second i n s t a r nymphal s t a g e s always d e v e l o p e d i n t o a l a t e s i r r e s p e c t i v e o f c o n d i t i o n s t o w h i c h t h e i r mothers were exposed. Other s t u d i e s have shown t h a t c r o w d i n g has no i n f l u e n c e on wing development. I n s e c t s born t o a l a t e a d u l t s , w hich were r e a r e d under e i t h e r crowded o r i s o l a t e d c o n d i t i o n s , always d e v e l o p e d i n t o a p t e r a e i r r e s p e c t i v e o f c o n d i t i o n s p r e v a l e n t d u r i n g t h e i r nymphal s t a g e s ( S u t h e r l a n d 1970; Mackay 1977) . A c c o r d i n g t o White (1965, 1968b), e n v i r o n m e n t a l l y i n d u c e d changes i n a p h i d polymorphism a r e mediated t h r o u g h t h e e n d o c r i n e system, p a r t i c u l a r l y t h e c o r p o r a a l l a t a (CA). These g l a n d s a r e s i t u a t e d b e h i n d t h e b r a i n and produce j u v e n i l e hormone (JH). As t h e n a t u r a l JH has not been i s o l a t e d from a p h i d s , t h e r o l e o f JH i n morphogenesis and r e p r o d u c t i o n can o n l y be i m p l i e d by e s t a b l i s h i n g t h e e f f e c t s o f j u v e n i l e hormone analogues (JHA) on development (White and Lamb 1968). I n t h e s e s t u d i e s , the JHA have been a d m i n i s t e r e d e i t h e r by d i r e c t t o p i c a l a p p l i c a t i o n o r by r e a r i n g a p h i d s on J H A - t r e a t e d p l a n t s . Such s t u d i e s have been performed on a l a t i f o r m l a r v a e o f jyL_ v i c i a e (Lees 1977, 1980), D o r a l i s fabae (Von Dehn 1963), B^ b r a s s i c a e (White 1968a, 1971; Hangartner e t a l . 1971), M_;_ p e r s i c a e (Tamaki 1973; Hrdy 1974; M i t t l e r e t a l . 1976), and i^L e u p h o r b i a e ( C l o u t i e r and P e r r o n 1975). The m o r p h o l o g i c a l r e s p o n s e s i n d u c e d by JHA 5 i n t h e s e s p e c i e s i n c l u d e d (1) t h e p r o d u c t i o n o f supernumerary nymphal i n s t a r s , (2) d e l a y e d metamorphosis, (3) malformed w i n g s , (4) abnormal cauda and g e n e t a l i a , (5) reduced f e c u n d i t y and/or (6) an i n c r e a s e d p r o p o r t i o n o f a p t e r a e . I n a d d i t i o n , M i t t l e r e t a l . (197 6) o b s e r v e d t h a t when f o u r t h i n s t a r s o f M. p e r s i c a e were t r e a t e d w i t h k i n o p r e n e , s c l e r o t i z a t i o n and p i g m e n t a t i o n were reduced b u t l a r v i p o s i t i o n i n c r e a s e d tempo-r a r i l y . F u r t h e r m o r e , t h e a u t h o r s c l a i m t h a t a l a t i f o r m l a r v a e t r e a t e d w i t h k i n o p r e n e had fewer secondary a n t e n n a l s e n s o r i a and no o c e l l i when t h e y emerged as a d u l t s . T h i s was sub-s t a n t i a t e d by s t u d i e s on v i c i a e , where i t was shown t h a t h i g h c o n c e n t r a t i o n s o f JHA reduced o r s u p p r e s s e d s c l e r o t i z a t i o n and development o f the o c e l l i b u t had no g r o s s e f f e c t s on t h e a n t e n n a l p l a c o i d organs (Lees 1977, 1980). However, m i c r o s -c o p i c e x a m i n a t i o n o f t h e organs i n d i c a t e d t h a t t h e y were s m a l l e r and l e s s numerous i n J H A - t r e a t e d a l a t e s t h a n i n c o n t r o l s (Lees 1980). As many o f t h e m o r p h o l o g i c a l f e a t u r e s s u p p r e s s e d by JHA t r e a t m e n t s a r e c h a r a c t e r i s t i c o f a l a t e a d u l t s b u t not immatures and a p t e r o u s a d u l t s , many a u t h o r s r e g a r d a p t e r o u s a d u l t females as b e i n g n e o t e n i c . That i s , t h e y r e t a i n l a r v a l c h a r a c t e r i s t i c s when r e p r o d u c t i v e l y mature. T h i s r e t e n t i o n o f j u v e n i l e c h a r a c t e r i s t i c s presumes t h e e x i s t e n c e o f h i g h JH t i t e r s d u r i n g embryonic and/or l a r v a l development. A d d i t i o n a l s u p p o r t f o r t h i s h y p o t h e s i s comes from s t u d i e s on a p t e r i f o r m s t a g e s where JHA have been shown t o e x h i b i t l i t t l e morphogenic a c t i v i t y (Hangartner e t a l . 1971; C l o u t i e r and P e r r o n 1975). * secondary a n t e n n a l s e n s o r i a ( a n t e n n a l p l a c o i d organs) 6 As d i s c u s s e d by M i t t l e r e t a l . (1976), t h e morphogenic e f f e c t s i n d u c e d by JHA a r e d i f f i c u l t t o i n t e r p r e t i n hormonal terms because l i t t l e i s known r e g a r d i n g t h e normal e n d o c r i n e m e d i a t i o n o f morphogenesis i n a p h i d s . I n o t h e r s p e c i e s , the l e v e l o f JH i n t h e haemolymph has been shown t o r e a c h i t s l o w e s t l e v e l d u r i n g t h e f i n a l nymphal s t a g e (cf. W i g g l e s w o r t h 1970; G i l b e r t 1975). T h i s d e c l i n e i n JH t i t e r e n a b l e s t h e i n s e c t t o metamorphose i n t o t h e a d u l t s t a g e c h a r a c t e r i s e d by f u l l y d e v e l o p e d w i n g s . As c u r r e n t t e c h n i q u e s p r e v e n t d i r e c t measurement o f JH l e v e l s i n a p h i d s , i n d i r e c t assessments have been made on t h e b a s i s o f t h e h i s t o l o g i c a l appearance o f t h e CA (White 1965; 1968b; E l l i o t t 1975). I n t h e s e s t u d i e s , i t was assumed t h a t changes i n t h e volume and n u c l e a r d i a m e t e r s o f t h e CA r e f l e c t t h e p a t t e r n o f JH s y n t h e s i s and r e l e a s e . That i s , a l a r g e g l a n d w i t h e n l a r g e d n u c l e i was b e l i e v e d a c t i v e , a s m a l l g l a n d i n a c t i v e . Based on t h e s e a s s u m p t i o n s , White and E l l i o t t i n d e p e n d e n t l y suggested t h a t t h e CA i n a p t e r o u s l a r v a e were v e r y a c t i v e whereas th e CA i n a l a t e l a r v a e were r e l a t i v e l y i n a c t i v e . Thus, h i g h JH t i t e r s i n a p t e r o u s morphs would f a v o u r t h e r e t e n t i o n o f j u v e n i l e c h a r a c t e r i s t i c s and s t i m u l a t e o v a r i a n growth. However, i n a d u l t s , t h e CA o f a p t e r o u s forms became i n a c t i v e whereas t h o s e i n a l a t e s became a c t i v e . I n t h e l a t t e r c a s e , t h e h i g h e r JH l e v e l s were b e l i e v e d t o f a v o u r t h e p r o d u c t i o n o f a p t e r o u s o f f s p r i n g . C o n v e r s e l y , i n a p t e r o u s a d u l t s , low JH l e v e l s were p o s t u l a t e d t o have l i t t l e e f f e c t on t h e form o f t h e o f f s p r i n g , so t h a t JH i n f l u e n c e s c o u l d be 7 m o d i f i e d p o s t n a t a l l y by v a r i o u s environmental f a c t o r s . H i s t o -l o g i c a l s t u d i e s appear t o c o n f i r m t h i s h y p othesis as White (1968b) demonstrated t h a t the mean n u c l e a r diameters of c e l l s i n the CA of aphids r e a r e d i n i s o l a t i o n (apteriforms) were s i g n i f i c a n t l y l a r g e r than those o f i n s e c t s r e a r e d t o g e t h e r ( a l a t i f o r m s ) . T h i s suggested t h a t i s o l a t i o n caused hyper-a c t i v i t y o f the CA. Recently the h i s t o l o g i c a l s t u d i e s o f White and E l l i o t t have come under great c r i t i c i s m i n t h a t other authors have e s t a b l i s h e d t h a t the n u c l e a r diameter and volume o f the CA are poor c r i t e r i a f o r a s s e s s i n g g l a n d u l a r a c t i v i t y . For example, e l e c t r o n microscopy s t u d i e s performed on v i c i a e demonstrated t h a t the volume and u l t r a s t r u c t u r e o f the CA from a l a t e - and apterous-producing a d u l t s were not d i f f e r e n t ( L e c k s t e i n 1976). Furthermore, crowding, which s t i m u l a t e s a l a t e p r o d u c t i o n had no e f f e c t on CA u l t r a s t r u c t u r e . T h e r e f o r e , c o n t r a r y to the s u g g e s t i o n of Lees (1967), L e c k s t e i n concluded t h a t the maternal CA was not i n v o l v e d i n the p r e n a t a l c o n t r o l o f wing develop-ment i n v i c i a e . Rather, the presence o f c o n s i d e r a b l e amounts o f smooth endoplasmic r e t i c u l u m i n the CA of apterous a d u l t s prompted L e c k s t e i n t o p o s t u l a t e t h a t the CA were i n a c t i v e i n these i n s e c t s ! However, i n most other i n s e c t s p e c i e s s t u d i e d , the CA have been shown to s t i m u l a t e o v a r i a n development ( c f . G i l b e r t 1976). Since apterous females are more fecund than a l a t e females (Blackman 1974, Mackay and W e l l i n g t o n 1975), the L e c k s t e i n hypothesis i s t e n a b l e o n l y i f some hormonal agent . 8 o t h e r t h a n JH r e g u l a t e s r e p r o d u c t i v e development i n female a p h i d s . As w i l l be d i s c u s s e d s h o r t l y , t h i s seems u n l i k e l y . A second c r i t i c i s m o f t h e t h e o r y t h a t JH s u p p r e s s e s wing development i n a p h i d s came from s t u d i e s performed on p e r s i c a e . U s i n g a r t i f i c i a l d i e t s , Applebaum e t a l . (1975) demonstrated t h a t two JHA ( c h l o r i n a t e d f a r n e s o i c a c i d and an i s o m e r i c JH m i x t u r e ) had no apparent p r e n a t a l o r p o s t n a t a l a p t e r i z i n g e f f e c t on p e r s i c a e . I n s t e a d , t h e compounds caused d e l a y e d development and h i g h m o r t a l i t y . The a u t h o r s viewed t h e s e e f f e c t s as p a t h o l o g i c a l and suggested t h a t exogeneous JHA t r e a t m e n t s m e r e l y d i s r u p t t h e i n t e r n a l hormonal m i l i e u . F u r t h e r -more, Applebaum e t a_l. s u g g e s ted t h a t a p h i d s a r e n o r m a l l y p r e s u m p t i v e a p t e r a t e s w i t h dormant wing r u d i m e n t s w h i c h are l a t e r s t i m u l a t e d by p o s t n a t a l l i p i d f r a c t i o n ( s ) . As i n d i c a t e d above, t h e r o l e o f JH i n a p h i d polymorphism i s i n doubt. No t h e o r y s t r o n g l y s u g g e s t s whether JH i s o r i s not i n v o l v e d i n wing development and i f i t i s i n v o l v e d , when and a t what s t a g e t h e hormone i s i m p o r t a n t . I n r e v i e w i n g t h e e v i d e n c e f o r and a g a i n s t hormonal c o n t r o l o f wing polymorphism i n a p h i d s , H a l e s (1976) s u g g e s t e d t h a t t h e r o l e o f JH, i f any, c o u l d be demonstrated o n l y w i t h new t e c h n i q u e s i n v o l v i n g t h e use o f a n t i - j u v e n i l e hormone o r a n t i - a l l a t o t r o p i c a g e n t s . A n t i - a l l a t o t r o p i c a g ents were d i s c o v e r e d by Bowers and h i s a s s o c i a t e s i n 197 6 when t h e y i s o l a t e d two chromene d e r i v a t i v e s from t h e b e d d i n g p l a n t , Ageratum haustonianum. In p r e l i m i n a r y s t u d i e s , two d e r i v a t i v e s , p r e c o c e n e - I and 9 precocene-II, were shown t o induce p r e c o c i o u s metamorphosis and prevent o v a r i a n development i n the milkweed bug, c o t t o n s t a i n e r , apple maggot, and bean b e e t l e . The e x t e n t of the responses to the precocenes v a r i e d w i t h dosage and time o f a p p l i c a t i o n . F u r t h e r s t u d i e s demonstrated t h a t precocene-II i n h i b i t e d JH b i o s y n t h e s i s i n P e r i p l a n e t a americana ( P r a t t and Bowers 1977), and induced i r r e v e r s i b l e d e g eneration o f the CA of a d u l t Oncopeltus f a s c i a t u s (Unnithan e t a l . 1977). In the migrat o r y l o c u s t , Locusta m i g r a t o r i a , treatment o f young nymphs with precocene-II (Pener et. a l . 1978; Nemec e t a l . 1978) or precocene-I (Pedersen 1978) l e d t o p r e c o c i o u s metamorphosis. The i n h i b i t o r y e f f e c t s o f the precocenes on the CA were almost immediate i n t h a t degenerative changes i n the glands began w i t h i n two h r s . o f treatment (Schoonveld 1979). Although t o p i c a l a p p l i c a t i o n o f precocene-I caused p r e c o c i o u s meta-morphosis i n the d e s e r t l o c u s t , S c h i s t o c e r c a g r e g a r i a , precocene-II was t o t a l l y i n a c t i v e when a p p l i e d t o p i c a l l y t o comparable stages (Paquin and Perron 1978; Unnithan e t a l . 1980). However, when S^ g r e g a r i a nymphs were exposed t o precocene-II r e s i d u e s i n petri-dishes f o r 24 h r s . , a hi g h p r o p o r t i o n o f the t r e a t e d nymphs metamorphosed p r e c o c i o u s l y (Unnithan et a l . 1980). Thus, b i o a s s a y methods can s t r o n g l y i n f l u e n c e the i n h i b i t o r y a c t i o n o f the precocenes on CA a c t i v i t y . Moreover, s e v e r a l authors have suggested t h a t the precocenes are o n l y i n h i b i t o r y when the CA are a c t i v e (Masner e t a l . 1979; Unnithan and N a i r 1979). 10 To d a t e , o n l y one s t u d y has i n v e s t i g a t e d t h e e f f e c t s o f p recocene on a p h i d morphogenesis and r e p r o d u c t i o n . Working on t h e pea a p h i d , A^ pisum, Mackauer e t a l . (1979) showed t h a t t o p i c a l a p p l i c a t i o n o f p r e c o c e n e - I I t o a p t e r o u s a d u l t s r e s u l t e d i n t h e p r o d u c t i o n o f a l a t e o f f s p r i n g even though c o n d i t i o n s f a v o u r e d t h e f o r m a t i o n o f a p t e r a e . The number o f a l a t e s produced was h i g h l y v a r i a b l e and depended upon when precocene was a p p l i e d . A l t h o u g h such e f f e c t s s u g g e s t e d t h a t p r e c o c e n e - I I has an a n t i a l l a t o t r o p i c ( a l a t e - i n d u c i n g ) e f f e c t i n a p h i d s , t h e compound d i d n o t cause s t e r i l i t y . However, as t h e d e c l i n e i n l a r v i p o s i t i o n i n p r e c o c e n e - t r e a t e d females was r e v e r s e d some-what by subsequent JH a p p l i c a t i o n s , i t would appear t h a t t h e CA may s t i m u l a t e r e p r o d u c t i o n i n a p h i d s . I n l i g h t o f t h e u n c e r t a i n t y o f t h e r o l e o f JH i n morpho-g e n e s i s i n M_j_ p e r s i c a e , k i n o p r e n e and p r e c o c e n e - I I were used as c h e m i c a l probes t o e s t a b l i s h t h e i n f l u e n c e o f JH on (1) metamorphosis, (2) wing development, (3) s c l e r o t i z a t i o n , (4) r e p r o d u c t i o n , and (5) d i f f e r e n t i a t i o n o f c e p h a l i c s e n s o r y s t r u c t u r e s . 11 MATERIAL AND METHODS A. REARING TECHNIQUES Green peach a p h i d s were o b t a i n e d from Dr. Forb e s a t t h e A g r i c u l t u r e Canada Re s e a r c h S t a t i o n , Vancouver. The a p h i d s were r e a r e d on Chi n e s e cabbage, B r a s s i c a e c h i n e n s i s _ . The p l a n t s were t r a n s f e r r e d i n t o mesh cages (36x40x39 cm.) l o c a t e d i n the Department o f P l a n t S c i e n c e greenhouse. The s t o c k c o l o n i e s were m a i n t a i n e d a t 16°- 18° C and 16L:8D p h o t o p e r i o d . To ensure v i g o r o u s c o l o n i e s , cabbage p l a n t s were r e p l a c e d as th e y d e t e r i o r a t e d . (a) A l a t i f o r m nymphs F o r s t u d i e s r e q u i r i n g a l a t i f o r m nymphs, newly-ecdysed nymphs were c o l l e c t e d from s t o c k c o l o n i e s o f a p t e r o u s v i r g i n o p a r a e w h i c h had been r e a r e d under crowded c o n d i t i o n s . To. ensure c o n t i n u o u s c r o w d i n g , .45 i n s e c t s were t r a n s f e r r e d i n t o a c l i p - c a g e (3.2 cm. diamet e r ) w h i c h was a t t a c h e d t o a l e a f o f a 3-week-old cabbage p l a n t ( F i g . 1 ) . The p l a n t s were p l a c e d i n a P e r c i v a l growth chamber and m a i n t a i n e d a t c o n d i t i o n s d e s c r i b e d above. When the a p p r o p r i a t e nymphal o r a d u l t s t a g e s had been r e a c h e d , t h e i n s e c t s were t r e a t e d w i t h the t e s t compound d e s c r i b e d i n S e c t i o n B ( a ) . (b) A p t e r i f o r m nymphs and a d u l t s A p t e r i f o r m nymphs were o b t a i n e d from a p t e r o u s and a l a t e v i r g i n o p a r a e w h i c h had been r e a r e d i n i s o l a t i o n . I n o r d e r t o m a i n t a i n i s o l a t i o n , t h e nymphs were r e a r e d s i n g l y 12 13 i n c l i p - c a g e s (Mackauer e t a l . 1979). The a p p r o p r i a t e nymphal o r a d u l t s t a g e s were t r e a t e d w i t h t e s t compound d e s c r i b e d i n S e c t i o n B . (c) A l a t e - p r o d u c i n g a p t e r o u s a d u l t s were o b t a i n e d by r e a r i n g newly-ecdysed a p t e r o u s a d u l t s i n crowded c o n d i t i o n s (20 i n s e c t s / c a g e ) . K i n o p r e n e was a p p l i e d t o t h e s e i n s e c t s w i t h i n 12 h r s . o f t h e i r emergence. To m a i n t a i n crowded c o n d i t i o n s among t h e i r progeny, a l l t h e o f f s p r i n g produced d a i l y were c o l l e c t e d and caged t o g e t h e r (40 i n s e c t s / c a g e ) . The o f f s p r i n g were examined d a i l y . B. EXPERIMENTAL COMPOUNDS (a) K i n o p r e n e t r e a t m e n t s The j u v e n i l e hormone analogue, k i n o p r e n e ( 2 - p r o p y n y l ( 2 E , 4 E ) - 3 , 7 , l l - t r i m e t h y l - 2 , 4 - d o d e c a d i e n o a t e ; ZR-777; Zoecon Chem. C o r p . ) , w h i c h has been shown t o be b i o l o g i c a l l y a c t i v e i n VL_ p e r s i c a e ( M i t t l e r e t a l . 1976; Boyd 1979), was p r e p a r e d i n d i s t i l l e d water c o n t a i n i n g 0.1% o f t h e w e t t i n g agent, Tween 20 ( p o l y o x y e t h y l e n e s o r b i t a n m o n o l a u r a t e ) . The l e t h a l and m o r p h o l o g i c a l e f f e c t s o f k i n o p r e n e were examined on a l l nymphal and a d u l t s t a g e s o f a p t e r i f o r m and a l a t i f o r m morphs. W i t h i n 2 h r s . o f m o l t i n g , the v a r i o u s s t a g e s were d i p p e d i n a 0.1% aqueous Tween 20 s o l u t i o n con-t a i n i n g v a r y i n g c o n c e n t r a t i o n s o f k i n o p r e n e . C o n t r o l s were t r e a t e d i n a s i m i l a r manner e x c e p t t h e y were d i p p e d i n a 0.1% 14 aqueous Tween 20 s o l u t i o n . Depending upon the s t u d y , the v a r i o u s t r e a t m e n t s were r e p l i c a t e d t h r e e t o s i x t i m e s . S t u d i e s on (1) a l a t i f o r m morphs i n c l u d e d 45 a p h i d s / r e p l i c a t e , (2) t h o s e on i s o l a t e d a p t e r i f o r m nymphs and a d u l t s i n c l u d e d one a p h i d / r e p l i c a t e and (3) t h o s e on crowded a p t e r o u s a d u l t s i n c l u d e d 20 i n s e c t s / r e p l i c a t e . The e f f e c t s o f k i n o p r e n e on m o r t a l i t y , metamorphosis, s c l e r o t i z a t i o n , wing f o r m a t i o n , f e c u n d i t y and d i f f e r e n t i a t i o n o f the o c e l l i and secondary a n t e n n a l s e n s o r i a were a s s e s s e d d a i l y f o r up t o 10 days f o l l o w i n g t r e a t m e n t , (b) P r e c o c e n e - k i n o p r e n e t r e a t m e n t s The a n t i - j u v e n i l e hormone compound, p r e c o c e n e - I I ( 6 , 7-dimethyl-2,2-dimethyl-chromene; A l d r i c h Chem. Co.) was s t o r e d under n i t r o g e n a t 6° C. I n p r e l i m i n a r y t e s t s , a p h i d s were exposed t o precocene v i a the f u m i g a t i o n method (Bowers e t a l . 1976). T h i s t e c h n i q u e i n v o l v e s c o a t i n g the bottom o f a g l a s s p e t r i - d i s h w i t h a p r e c o c e n e - a c e t o n e s o l u t i o n , a l l o w i n g t h e a c etone t o e v a p o r a t e t h e n i n t r o d u c i n g t h e a p h i d s i n t o the p e t r i - d i s h f o r v a r y i n g i n t e r v a l s . A l t h o u g h the b i o a s s a y has been used s u c c e s s f u l l y on o t h e r s p e c i e s (Unnithan e t a l . 1980) , the method p r o v e d i n a p p r o p r i a t e on p e r s i c a e because o f i n c o n s i s t e n t e f f e c t s . T h i s i n c o n s i s t e n c y may r e f l e c t one major s h o r t c o m i n g o f f u m i g a t i o n i n t h a t i t i s i m p o s s i b l e t o a d m i n i s t e r a u n i f o r m d e f i n a b l e dose o f precocene t o each i n s e c t . To a c c o m p l i s h t h i s , a method was 15 developed f o r t o p i c a l l y a p p l y i n g precocene. I n i t i a l l y , precocene-II s o l u t i o n s were prepared i n acetone (Mackauer e t a l . 1979). However, t h i s proved u n s a t i s f a c t o r y because the acetone was very t o x i c t o the aphids v i z - 9 0 % m o r t a l i t y . T h i s problem was avoided by d i s s o l v i n g precocene i n dimethyl s u l f o x i d e (DMSO). S o l u t i o n s of precocene-DMSO were drawn i n t o a 100 u l Hamilton m i c r o - s y r i n g e which was mounted on a m i c r o - a p p l i c a t o r (Instrumentation S p e c i a l t i e s Comp.). By a l t e r i n g the concen-t r a t i o n o f precocene or a d j u s t i n g the volume a p p l i e d , the method enabled me to apply minute but p r e c i s e amounts of precocene t o the abdomen of each aphid. In most nymphal and a d u l t t e s t s , 0.5 ug precocene was a p p l i e d to each i n s e c t . However, when t h i s dose was a d m i n i s t e r e d to apterous a d u l t s , i t n e a r l y t o t a l l y prevented r e p r o d u c t i o n or proved t o x i c t o the few o f f s p r i n g produced. T h i s d i f f i c u l t y was circumvented by a p p l y i n g 0.2 ug precocene to apterous a d u l t s . C o n t r o l s were t r e a t e d i n an i d e n t i c a l manner except t h a t o n l y DMSO was a p p l i e d . A f t e r treatment, the i n s e c t s were t r a n s f e r r e d i n t o c l i p - c a g e s and p l a c e d on cabbage p l a n t s i n a P e r s i v a l growth chamber. The l e t h a l and m o r p h o l o g i c a l e f f e c t s were observed d a i l y f o r up to 10 days. In a d d i t i o n , 4 days a f t e r a d u l t emergence, h a l f o f the p r e c o c e n e - t r e a t e d i n s e c t s were t r e a t e d w i t h 65 ppm kinoprene. 16 (c) S t a t i s t i c a l a n a l y s i s S t a t i s t i c a l d i f f e r e n c e s between the c o n t r o l and kino p r e n e - p r e c o c e n e - t r e a t e d groups were determined u s i n g the two sample mean t e s t a t the 5% s i g n i f i c a n c e l e v e l . T h e v a l u e of T was determined u s i n g the f o l l o w i n g formula Where: X,= mean of c o n t r o l i n s e c t s : Xj= mean of t r e a t e d i n s e c t s , n= n u m t > e r of r e p l i c a t e s i n c o n t r o l i n s e c t s n= number of r e p l i c a t e s i n t r e a t e d i n s e c t s Sp= pooled v a r i a n c e In s t u d i e s i n v o l v i n g .precocene - t r e a t e d , k i n o p r e n e - t r e a t e d and c o n t r o l i n s e c t s , mean d i f f e r e n c e a t the 5% l e v e l were t e s t e d u s i n g Duncans M u l t i p l e Range test(U.B.C.MFAV Computer Programe). t X , - * 2 17 RESULTS A. KINOPRENE TREATMENTS (a) F i r s t i n s t a r a l a t i f o r m nymphs When f i r s t i n s t a r a l a t i f o r m nymphs were dipped i n a s o l u t i o n c o n t a i n i n g 65 ppm kinoprene, l e t h a l e f f e c t s were immediately apparent (Table l a ) . The % m o r t a l i t y observed i n the JHA-treated group was s i g n i f i c a n t l y g r e a t e r than i n the c o n t r o l s d u r i n g the f i r s t i n s t a r and each sub-sequent nymphal stage. U n l i k e the f o u r t h i n s t a r c o n t r o l s , which molted d i r e c t l y i n t o a d u l t s , 87.3% of the s u r v i v i n g a l a t i f o r m nymphs i n the kinoprene treatments underwent a supernumerary molt (Table l b ) . S i g n i f i c a n t m o r t a l i t y was observed a t the molt and d u r i n g the f i f t h i n s t a r stadium. By the time o f a d u l t e c d y s i s , 95.4% o f the nymphs t r e a t e d w i t h kinoprene had d i e d . In the c o n t r o l s , 85.1% of the f i r s t i n s t a r nymphs developed i n t o normal a l a t e s , 9.6% developed i n t o apterae. In c o n t r a s t , no normal a l a t e s were produced i n the k i n o p r e n e - t r e a t e d group. Instead, three malformed a l a t e s ( r e p r e s e n t i n g 2.2% o f the o r i g i n a l p o p u l a t i o n ) and three a p p a r e n t l y normal apterae (2.2%) were produced i n the three r e p l i c a t e s . Although, m o l t i n g was s l i g h t l y delayed, the apterous i n s e c t s d i d not undergo a supernumerary molt. Two days a f t e r a d u l t emergence, v i r t u a l l y 100% m o r t a l i t y was observed i n the t r e a t e d aphids. No o f f s p r i n g were produced by the k i n o p r e n e - t r e a t e d aphids d u r i n g t h i s p e r i o d 18 Table l a . S e q u e n t i a l l e t h a l e f f e c t s o f 65 ppm kinoprene a p p l i e d to f i r s t i n s t a r a l a t i f o r m nymphs. Numbers i n parentheses r e p r e s e n t cumulative m o r t a l i t y v a l u e s . In t h i s and remaining t a b l e s , means on the same row f o l l o w e d by s i m i l a r s u p e r s c r i p t s 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% l e v e l (3 r e p l i c a t e s / t r e a t m e n t , 45 i n s e c t s / r e p l i c a t e ) . % m o r t a l i t y Stage C o n t r o l K i n o p r e n e - t r e a t e d 1st i n s t a r 2.2±1.3 a 3.7±1.5 b 2nd i n s t a r 1.5±0.8 a(3.7±1.5) 3.0±2.0 b (6.6±1.3) 3rd i n s t a r 1.5±0.8 a(3.2 + 1.9) 3.0±0.7 b (9.6±2.0) 4th i n s t a r 0.0±0.0 a(5.2 + 1.9) 0.7±0.8 b(10.3+2.0) Supernumerary molt N.A. 41.614.1 !(51.9±3.9) Supernumerary i n s t a r N.A. 43.6±3.9 (95.4±0.0) A d u l t (2-day-old) 0.0±0.0 a(5.2±1.9) 4.4+0.0 b(99.8±0.0) Table l b . Developmental e f f e c t s o f kinoprene on s u r v i v i n g f i r s t i n s t a r a l a t i f o r m nymphs. % o r i g i n a l p o p u l a t i o n Stage C o n t r o l K i n o p r e n e - t r e a t e d Supernumerary i n s t a r s 0±0 87.3±0.7 Malformed a l a t e s 0±0 2.2±1.3 Normal a l a t e s 85.113.9 0.010.0 Normal apterae 9.612.0 a 2.2±1.3 b 19 whereas the c o n t r o l s produced 2-4 o f f s p r i n g / d a y . Before d e s c r i b i n g the a b e r r a t i o n s induced by kinoprene, i t would seem a p p r o p r i a t e to b r i e f l y d e s c r i b e some of the important m o r p h o l o g i c a l f e a t u r e s e x h i b i t e d by normal a l a t e and apterous a d u l t s . As i l l u s t r a t e d i n the scanning e l e c t r o n photomicrographs ( F i g s . 2a-c), f e a t u r e s t y p i c a l of a l a t e a d u l t s i n c l u d e a h e a v i l y s c l e r o t i z e d thorax, d a r k l y pigmented body, w e l l - d e v e l o p e d o c e l l i and numerous secondary antennal s e n s o r i a . In c o n t r a s t , apterous a d u l t s are c h a r a c t e r i z e d by reduced s c l e r o t i z a t i o n , and an un-pigmented body ( F i g . 2d), and the absence of o c e l l i ( F i g . 2e). In both morphs, the cauda and g e n i t a l p l a t e are prominent. The k i n o p r e n e - t r e a t e d i n s e c t s , which molted i n t o abnormal a d u l t o i d s , e x h i b i t e d many j u v e n i l e c h a r a c t e r i s t i c s and f e a t u r e s i n t e r m e d i a t e between a l a t e and apterous a d u l t s . Compared to normal a l a t e s , they had g r e a t l y reduced wings ( F i g . 3a, b) which .more c l o s e l y resembled rudiments found i n f o u r t h i n s t a r a l a t i f o r m nymphs. L i k e f o u r t h i n s t a r s and apterous a d u l t s , the thorax was u n s c l e r o t i z e d and the c u t i c l e unpigmented. Although o c e l l i were prese n t ( F i g . 3c), they appeared abnormal and l e s s developed than i n a l a t e a d u l t s . The secondary antennal s e n s o r i a were shrunken and deformed ( F i g . 3d) whereas the presumptive cauda and g e n i t a l p l a t e were more nymphal than a d u l t i n appearance. 20 F i g . 2a. D o r s a l view o f normal a l a t e a d u l t showing the h e a v i l y s c l e r o t i z e d thorax and d a r k l y pigmented body (2 3 X). b. D o r s a l view of the head of normal a l a t e a d u l t showing w e l l - d e v e l o p e d o c e l l i (187 X). c. Secondary antennal s e n s o r i a o f normal a l a t e a d u l t (937 X). • d. D o r s a l view of normal apterous a d u l t showing the absence of s c l e r o t i z a t i o n i n the thorax (65 X). D o r s a l view o f head of normal apterous a d u l t showing the absence of o c e l l i (187 X). 21 F i g . 3a. T y p i c a l d e f o r m i t i e s p r e s e n t i n malformed a l a t e a d u l t o i d s which had been t r e a t e d w i t h kinoprene as f i r s t i n s t a r nymphs (23 X). b. D o r s a l view o f thorax showing the e f f e c t on wings and g e n i t a l i a (187 X). c. D o r s a l view of head capsule showing the e f f e c t on o c e l l i (187 X). d. E f f e c t o f kinoprene on secondary antennal s e n s o r i a (1873 X). 22 (b) Second i n s t a r a l a t i f o r m nymphs When kinoprene was a p p l i e d t o second i n s t a r a l a t i -form nymphs, the i n i t i a l m o r t a l i t y was not as h i g h as i n the p r e v i o u s study (Table 2a). By the end o f the f o u r t h i n s t a r , 8-9% m o r t a l i t y was observed i n the k i n o p r e n e - t r e a t e d and c o n t r o l i n s e c t s . Before m o l t i n g i n t o a d u l t s , 81.4% of the JHA-treated aphids underwent a supernumerary molt (Table 2b). About 10% m o r t a l i t y o c c u r r e d d u r i n g t h i s stadium so t h a t by the time of a d u l t emergence, 18.4% of the t r e a t e d i n s e c t s had d i e d . In the c o n t r o l s , 80.7% of the second i n s t a r nymphs developed i n t o normal a l a t e s , 11% developed i n t o a p terae. As i n the p r e v i o u s experiment, no normal a l a t e s were produced i n the k i n o p r e n e - t r e a t e d group. In-stead, 71.8% o f the i n s e c t s developed i n t o malformed a l a t e s and 9.6% i n t o normal apterae. Although m o l t i n g was s l i g h t l y delayed, the k i n o p r e n e - t r e a t e d nymphs which molted i n t o apterous a d u l t s d i d not undergo a supernumerary molt. High m o r t a l i t y (65%) was observed w i t h i n 2 days o f a d u l t emergence and by the f o u r t h day, a l l i n s e c t s had d i e d i n the t r e a t e d group. During t h i s p e r i o d , no o f f s p r i n g were produced by t r e a t e d aphids whereas c o n t r o l s reproduced n o r m a l l y. K i n o p r e n e - t r e a t e d i n s e c t s , which molted i n t o malformed a d u l t o i d s , resembled nymphs and apterous a d u l t s . Again, the wings were undeveloped and the c u t i c l e remained 23 Table 2a. S e q u e n t i a l l e t h a l e f f e c t s o f 65 ppm kinoprene a p p l i e d to second i n s t a r a l a t i f o r m nymphs. % m o r t a l i t y Stage C o n t r o l K i n o p r e n e - t r e a t e d 2nd i n s t a r 3rd i n s t a r 4th i n s t a r Supernumerary molt Supernumerary i n s t a r A d u l t (2-day-old) A d u l t (4-day-old) 2.9±1.9 a 2.2±0.0 a(8.0±1.6) 2.9±0.7 a(8.0±1.6) N.A. N.A. (8.Oil.6) O.OiO.O (8.Oil.6) O.OiO.O (8.0±1.6) 4.4±1.3 b 2.9±0.8 a( 7.3±0.8) 1.5±0.8 b( 8.811.3) O.OiO.O ( 8.8±1.3) 9.712.0 (18.5±1.5) 65.8±8.1 (84.316.6) 15.516.6 (99.810.0) Table 2b. Developmental e f f e c t s of kinoprene on s u r v i v i n g second i n s t a r a l a t i f o r m nymphs. % o r i g i n a l p o p u l a t i o n Stage C o n t r o l K i n o p r e n e - t r e a t e d Supernumerary i n s t a r s 0+0 81.4+2.0 Malformed a l a t e s 010 71.812.0 Normal a l a t e s 80.712.0 0.0+0.0 Normal apterae 11.011.3 a 9.610.8 b 24 F i g . 4a. D e f o r m i t i e s produced i n malformed a l a t e a d u l t o i d s w h i c h had been t r e a t e d w i t h k i n o p r e n e as second i n s t a r nymphs (23 X ) . b. M a g n i f i e d view o f wing r u d i m e n t s (93 X ) . c. D o r s a l v i e w o f head c a p s u l e showing t h e e f f e c t on o c e l l i (187 X ) . d. E f f e c t o f k i n o p r e n e on secondary a n t e n n a l s e n s o r i a (2810 X ) . 25 u n s c l e r o t i z e d and unpigmented ( F i g . 4 a , b ) . I n a d d i t i o n , o c e l l i were c o m p l e t e l y a b s e n t ( F i g . 4c) and t h e a n t e n n a l s e n s o r i a deformed ( F i g . 4 d ) . A l t h o u g h the cauda had n o t dev e l o p e d f u l l y , i t was more prominent t h a n i n t h e p r e v i o u s s t u d y on f i r s t i n s t a r s . (c) T h i r d i n s t a r a l a t i f o r m nymphs The l e t h a l and m o r p h o l o g i c a l e f f e c t s o f k i n o p r e n e on t h i r d i n s t a r nymphs are shown i n T a b l e s 3a and 3b. U n l i k e the c o n t r o l s w h i c h m o l t e d n o r m a l l y and d e v e l o p e d i n t o p r i m a r i l y a l a t e a d u l t s , 86.7% o f t h e t r e a t e d i n s e c t s under-went a supernumerary m o l t . U n t i l t h i s t i m e , k i n o p r e n e had no s i g n i f i c a n t e f f e c t on m o r t a l i t y . However, compared t o the c o n t r o l s , m o r t a l i t y r o s e a b r u p t l y i n t h e t r e a t e d i n s e c t s j u s t a f t e r a d u l t emergence and a l l i n s e c t s d i e d by t h e s i x t h day. D u r i n g t h i s p e r i o d no o f f s p r i n g were produced. A l -though no normal a l a t e s were produced i n t h e J H A - t r e a t e d group, 6.7% o f t h e i n s e c t s i n t h e t h r e e r e p l i c a t e s d e v e l o p e d i n t o a p t e r a e a f t e r u n d e r g o i n g a s l i g h t d e l a y i n m o l t i n g . I n the c o n t r o l s , about 80% o f the t h i r d i n s t a r nymphs d e v e l o p e d i n t o normal a l a t e s and 11% d e v e l o p e d i n t o a p t e r a e . K i n o p r e n e - t r e a t e d i n s e c t s , w hich m o l t e d i n t o mal-formed a d u l t o i d s , r esembled nymphs and a p t e r o u s a d u l t s . The c u t i c l e remained u n s c l e r o t i z e d and unpigmented ( F i g . 5 a ) . The g e n i t a l p l a t e and cauda were a l s o w e l l - f o r m e d . A l t h o u g h 26 Table 3a. S e q u e n t i a l l e t h a l e f f e c t s o f 65 ppm kinoprene a p p l i e d t o t h i r d i n s t a r a l a t i f o r m nymphs. % m o r t a l i t y Stage C o n t r o l K i n o p r e n e - t r e a t e d 3rd i n s t a r 4th i n s t a r Supernumerary molt A d u l t (3-day-old) A d u l t (6-day-old) 5.9±1.9 a 3.0±0.7 a(8.9±1.3) N.A. O.OiO.O (8.9±1.3) O.OiO.O (8.9+1.3) 5 . 1 i l . 3 a 1.5i0.7 b( 6.6il.3) O.OiO.O ( 6.6il.3) 73.2i3.4 (79.8±2.5) 19.9±2.5 (99.7i0.7) Table 3b. Developmental e f f e c t s o f kinoprene on s u r v i v i n g t h i r d i n s t a r a l a t i f o r m nymphs. % o r i g i n a l p o p u l a t i o n Stage C o n t r o l K i n o p r e n e - t r e a t e d Supernumerary i n s t a r s OiO 86.7i2.2 Malformed a l a t e s N.A. 86.7i2.2 Normal a l a t e s 80.0i2.2 O.OiO.O Normal apterae 11.0±1.3 a 6 . 7 i l . 3 b 27 F i g . 5 a . D e f o r m i t i e s produced i n malformed a l a t e a d u l t o i d s which had been t r e a t e d w i t h k i n o p r e n e as t h i r d i n s t a r nymphs (23 X ) . b. M a g n i f i e d v i e w o f b a l l o o n - s h a p e d wings (74 X ) . c. D o r s a l view o f head c a p s u l e showing t h e e f f e c t on o c e l l i (187 X ) . d. E f f e c t o f k i n o p r e n e on secondary a n t e n n a l s e n s o r i a (2810 X ) . 9LT-A 28 wings were s l i g h t l y reduced compared t o normal a l a t e s , they were balloon-shaped and f l u i d - f i l l e d ( F i g . 5b). Some wing v e n a t i o n was apparent. O c e l l i were p r e s e n t ( F i g . 5 c ) , but not as developed as i n normal a l a t e s . In a d d i t i o n , the antennal s e n s o r i a were deformed ( F i g . 5d). (d) F o u r t h i n s t a r a l a t i f o r m nymphs When a p p l i e d t o f o u r t h i n s t a r nymphs, kinoprene had l e s s pronounced e f f e c t s on m o r t a l i t y , morphogenesis, and r e p r o d u c t i o n than i n e a r l i e r t r e a t e d i n s t a r s (Table 4a and 4b). Although the % m o r t a l i t y observed d u r i n g the f o u r t h i n s t a r o f the t r e a t e d i n s e c t s was s i g n i f i c a n t l y g r e a t e r than the c o n t r o l s (Table 4a), n e a r l y 90% of the t r e a t e d i n s e c t s molted d i r e c t l y i n t o a d u l t s (Table 4b). However, e c d y s i s was delayed s l i g h t l y as c o n t r o l a d u l t s molted 6-7 h r s . sooner than k i n o p r e n e - t r e a t e d i n s e c t s . In the c o n t r o l s , 94.5% of the f o u r t h i n s t a r nymphs developed i n t o normal a l a t e s , 0.7% developed i n t o apterae. In the t r e a t e d i n s e c t s , 78.5% de-veloped i n t o a p p a r e n t l y normal a l a t e a d u l t s , about 12% i n t o malformed a l a t e s , and 3.7% i n t o normal apterae. Up to two days a f t e r a d u l t emergence, kinoprene had no s i g n i f i c a n t l e t h a l e f f e c t . A f t e r t h i s , m o r t a l i t y rose s i g n i f i c a n t l y as compared to c o n t r o l s and a l l i n s e c t s had d i e d by the seventh day. No s i g n i f i c a n t e f f e c t on r e p r o d u c t i o n was observed d u r i n g t h i s p e r i o d . 29 Table 4a. S e q u e n t i a l l e t h a l e f f e c t s o f 65 ppm kinoprene on f o u r t h i n s t a r a l a t i f o r m nymphs. % m o r t a l i t y Stage C o n t r o l K i n o p r e n e - t r e a t e d 4th i n s t a r ' 4.4±1.3 a 5.9±2.0 b A d u l t (3-day-old) 0.010.0 1.5±0.7(7.4±1.4) A d u l t (4-day-old) O.OiO.O 92.7±1.4 (100±0.0) Table 4B. Developmental e f f e c t s o f kinoprene on s u r v i v i n g f o u r t h i n s t a r a l a t i f o r m nymphs. % o r i g i n a l p o p u l a t i o n Stage C o n t r o l K i n o p r e n e - t r e a t e d Malformed a l a t e s Normal a l a t e s Normal apterae 0±0 94.8±0.7 a 0.7±0.7 a 11.8+4.1 78.5±4.9 b 3.7±0.7 b 30 F i g . 6a. V e n t r a l view of malformed a l a t e a d u l t s which had been t r e a t e d w i t h kinoprene as a f o u r t h i n s t a r nymph (32 X). b. D o r s a l view of head capsule showing the e f f e c t on o c e l l i (187 X). c. E f f e c t o f kinoprene on secondary antennal s e n s o r i a (1873 X). 31 U n l i k e , e a r l i e r nymphal s t a g e s , k i n o p r e n e had l e s s pronounced e f f e c t s on f o u r t h i n s t a r a l a t i f o r m nymphs. A l t h o u g h a l l t h e t r e a t e d had normal s i z e d wings w i t h f u l l y d e v e l o p e d cauda, t h e i r c u t i c l e s t i l l remained u n s c l e r o t i z e d and unpigmented ( F i g . 6 a ) . A f t e r f i v e days, the t e r m i n a l p o r t i o n o f t h e wings d r i e d up and wings became w r i n k l e d . A l t h o u g h t h e o c e l l i were w e l l d e v e l o p e d ( F i g . 6b) as i n normal a l a t e s , t h e i r s e n s o r i a were s l i g h t l y deformed ( F i g . 6c) . (e) A p t e r i f o r m nymphs o f a p t e r o u s a d u l t s P a r a l l e l e x p e r i m e n t s were a l s o c o n d u c t e d on a l l f o u r i n s t a r s o f a p t e r i f o r m l a r v a e b o r n t o a p t e r o u s a d u l t s . As i n t h e p r e v i o u s s t u d i e s , t h e i n s e c t s were i n i t i a l l y d i p p e d i n 65 ppm k i n o p r e n e . However, n e a r l y 9 0% m o r t a l i t y o c c u r r e d w i t h i n 24 h r s . a f t e r d i p p i n g . To a v o i d t h e s e l e t h a l e f f e c t s , subsequent e x p e r i m e n t s were performed u s i n g 10 ppm k i n o p r e n e . L i k e t h e c o n t r o l s , a l l k i n o p r e n e - t r e a t e d i n s e c t s d e v e l o p e d i n t o normal a p t e r o u s a d u l t s . However, compared t o the c o n t r o l s , e c d y s i s was d e l a y e d about 1 day i n t r e a t e d f i r s t and second i n s t a r nymphs and about 8 h r s . i n t r e a t e d t h i r d and f o u r t h i n s t a r nymphs. U n l i k e k i n o p r e n e - t r e a t e d a l a t i f o r m nymphs, a p t e r i f o r m nymphs d i d n o t undergo any supernumerary m o l t s . The e f f e c t s o f t h e t r e a t m e n t s on f e c u n d i t y o f t h e 32 emergent females were a l s o assessed. O v e r a l l , no s i g n i f i c a n t d i f f e r e n c e s were observed between the c o n t r o l s and kinoprene-t r e a t e d i n s e c t s (Table 5 ) . Each female i n both groups produced an average 3.2 o f f s p r i n g / d a y over the 10-day a s s e s s -ment p e r i o d . In t o t a l , c o n t r o l females produced 29-32 o f f s p r i n g whereas k i n o p r e n e - t r e a t e d females produced 31-33 o f f s p r i n g . The d a i l y e f f e c t s o f the treatments on the e v e n t u a l f e c u n d i t y o f the four i n s t a r s are shown i n F i g s . 7-10. In a l l cases, l a r v a e were u s u a l l y produced w i t h i n 24 h r s . of a d u l t emergence. F e c u n d i t y rose s h a r p l y on the second day and reached peak l e v e l s by the 5th o r 6th day when i t s t a b i -l i z e d . Maximum mean d a i l y f e c u n d i t y observed d u r i n g t h i s p e r i o d v a r i e d from 4.3 to 5.6 i n c o n t r o l s and from 4.5 to 4.6 i n the JHA-treated i n s e c t s . However, a f t e r t h i s , r e p r o -d u c t i o n decreased' s l o w l y so t h a t by the 10th day, mean fecun-d i t y ranged between 2.6 to 3.0 and 2.6 to 3.1 i n the c o n t r o l and t r e a t e d i n s e c t s , r e s p e c t i v e l y . (f) A p t e r i f o r m nymphs o f a l a t e a d u l t s Compared to a p t e r i f o r m nymphs of apterous a d u l t s , a p t e r i f o r m nymphs born t o a l a t e a d u l t s , were g e n e r a l l y s m a l l e r and more s e n s i t i v e to kinoprene. Over 9 0% of the i n s e c t s d i e d w i t h i n 12 h r s . of kinoprene-treatment. To a v o i d t h i s , subsequent experiments were performed w i t h 10 ppm kinoprene. A l l the i n s e c t s i n both the c o n t r o l and t r e a t e d Table 5. O v e r a l l e f f e c t o f 10 ppm kinoprene on the f e c u n d i t y of a p t e r i f o r m nymphs of apterous a d u l t s up t o 10 days a f t e r a d u l t emergence (5-6 r e p l i c a t e s / t r e a t m e n t ; 1 one i n s e c t / r e p l i c a t e ) . Average fecundity/female/day Stage t r e a t e d C o n t r o l K i n o p r e n e - t r e a t e d 1s t i n s t a r 2nd i n s t a r 3rd i n s t a r 4th i n s t a r 3.2±0.0 3 .2±0.l a 3.2±0.2 a 3.2±0.0 a 3.2±0 .0 a 3.2±0.1 a 3.1±0 .0 a 3.2±0.0 a i \ I 1 ! ! ! i 1 2 3 4 5 6 7 8 9 1 0 Age (days) F i g u r e 7. F e c u n d i t y of normal aphids ( •— • ) and those t r e a t e d with 10 ppm kinoprene ( A) as f i r s t i n s t a r a p t e r i f o r m l a r v a e of apterous a d u l t s . cQ S-H fD 00 L-. u_i hrj f_) O fD 4 O < T 3 $_ OJ ^ 3 CD" 3 Q> H-0 * * rt OJ o CD CD * 5 O CD r_ w — Fecundity (offspring/female/day) o Hi 3 O n 3 . 0) 0) fr Oi I PJ C ! U M • 3^ rt I H-cn I C-• ^ cn co cn CD o O 3 ' P 3 cn rt rt 0) 3 C-0) 3" o cn 0) CD T3 rt rt CD H l-i CD H- 0) Hi rt O CD 3 Cb s: rt 3" > LQ CD P i OJ cn to KJ I-o CO >o 1— *1 CD l _ . l _ . h j 0) O fD H O <V C OJ 3 fD 3 f _ I-1-O *• r t H i H - " < PJ O r t H fD fD H 3 O fD i i F e c u n d i t y (offspring/female/day) o H i O l-i 3 OJ • PJ d t- 1 r t cn TJ p-cn I OJ 3 OJ tn r t er H -c_ cn CL r t r t H er O OJ cn TJ fD r t fD r t H h H - fD H i 0) O r t H fD B Ch : t, •rt er -r— C n co fD 0) cn Cn O CO NO 9£ 1 J ! i l i i i I : i ! 1 2 3 4 5 6 7 8 9 10 Age (days) co F i g u r e 10. F e c u n d i t y of normal aphid (• • ) and those t r e a t e d with ^ 10 ppm kinoprene (A •<->) as f o u r t h i n s t a r a p t e r i f o r m l a r v a e o f apterous a d u l t s . 38 groups d e v e l o p e d i n t o n o r m a l - l o o k i n g a p t e r o u s a d u l t s . However, l i k e i n the p r e v i o u s e x p e r i m e n t s , m o l t i n g was d e l a y e d about 1 day i n t r e a t e d f i r s t and second i n s t a r nymphs and 7 o r 8 h r s . i n t h i r d and f o u r t h i n s t a r s . A g a i n , J H A - t r e a t e d nymphs d i d n o t undergo any supernumerary s t a g e b e f o r e m o l t i n g i n t o a d u l t s . T a b l e 6 shows t h a t k i n o p r e n e had no s i g n i f i c a n t e f -f e c t on r e p r o d u c t i o n . Over a 10-day p e r i o d , 2.8 t o 3.2 o f f -s p r i n g were produced d a i l y by t h e c o n t r o l and k i n o p r e n e -t r e a t e d f e m a l e s . I n a l l i n s t a r s . , l a r v i p o s i t i o n began w i t h i n 2 4 h r s . o f a d u l t emergence ( F i g s . 11-14). R e p r o d u c t i o n r a t e s r o s e r a p i d l y and r e a c h e d a peak by t h e 5 t h o r 6 t h day. D u r i n g t h i s p e r i o d , maximum mean d a i l y f e c u n d i t y v a r i e d from 4.0 t o 4.8 i n t h e c o n t r o l s , and from 4.0 t o 4.4 i n t h e t r e a t e d i n s e c t s . A f t e r t h i s , r e p r o d u c t i o n d e c r e a s e d so t h a t by the 1 0 t h day, mean f e c u n d i t y ranged between 2.6 t o 3.0 and 2.6 - 3.2 i n c o n t r o l and t r e a t e d i n s e c t s , r e s p e c t i v e l y , (g) A p t e r o u s a d u l t s ( a p t e r a e - p r o d u c e r s ) U n l i k e a p t e r i f o r m nymphs, newly ecdysed a p t e r o u s a d u l t s were l e s s s e n s i t i v e t o 65 ppm k i n o p r e n e as o n l y 10% m o r t a l i t y was o b s e r v e d . As i n p r e v i o u s s t u d i e s , k i n o p r e n e had no s i g n i f i c a n t e f f e c t on r e p r o d u c t i o n ( F i g . 1 5 ) . I n b o t h c o n t r o l and k i n o p r e n e - t r e a t e d f e m a l e s , maximum d a i l y f e c u n d i t y o c c u r r e d on the 6 t h day. However, a f t e r t h i s , Table 6. O v e r a l l e f f e c t of 10 ppm kinoprene on the f e c u n d i t y of a p t e r i f o r m nymphs of a l a t e a d u l t s (up t o 10 days a f t e r a d u l t emergence (5-6 r e p l i c a t e s / t r e a t m e n t , one i n s e c t / r e p l i c a t e ) . Average fecundity/female/day Stage t r e a t e d C o n t r o l K i n o p r e n e - t r e a t e d 1st i n s t a r 2nd i n s t a r 3rd i n s t a r 4th i n s t a r 2.9±0.1 C 3.2±0.1 J 2.8±0.1 J 3.0±0 a 2.9±0.1 3.0±0.1* 3.0±0 a 3.0±0.3 £ f-fD Fecundity (offspring/female/day) CO O H ^ hh O fD O 0) 'O pj 3 r t (D 0) 3 Ch O c •« H H r t fD cn 3 . fD W r t o hh 3 O 1 &) I *v I tr. I H -i Oi • cn P> cn hh H -hi cn r t — P) 3 cn Oi r t hi r t 3 J O pj cn ^ fD r t CD r t hi CD p> r t CD Oi i— 1 s: pj p. hi < P) CD r t 3* co > CD Oi P> <^ cn O i o CO >o I — h d H F e c u n d i t y (offspring/female/day) d 3 O M ^ Hi O fD O P> 13 M 13 pj g rt (D W rt Cu O O d 13 Hi M H rt fD 3 CD 3 O • fD H 3 f |-! » ! H-^ cn PJ — . cn • cn fD o O 3 Ch H-3 cn rt PJ H PJ 13 rt fD i-i PJ 3 Ch rt 3" O cn fD rt H Hi fD O P) h rt 3 CD Ch H-rt tr ro ho CO > CD PJ cn o C O •o CO O n 4 H-iQ 0 H CD M to 0 I—1 hrj •Hi O CD O r-"Tj OJ g r+ CD ;v r t c_ o o r_ TS H i H H r t CD 3 01 3 O • CD H 3 — 0) J OJ I . H-I cn F e c u n d i t y ( o f f s p r i n g / f e m a l e / d a y ) c O-0) cn r t cr H-i-i Pi H-3 0) cn Pi r t 0) H r t cr O 0) cn CD r t CD r t H H H- CD H i 0) O r t i-i CD 3 Pi 3 H-r t cr to rO C O > cQ CD Pi 0) cn o C O to Oi —I -fr-e—H 3fr 1 2 3 4 5 6 7 8 9 10 Age (days) F i g u r e 14. F e c u n d i t y of normal aphids (• • ) and those t r e a t e d w i t h 10 ppm kinoprene (- _) as f o u r t h i n s t a r a p t e r i f o r m l a r v a e of a l a t e a d u l t s . T J ! I L 1 2 3 4 5 6 7 8 9 10 Age (days) F i g u r e 15. F e c u n d i t y o f normal a p h i d s (•; •) and those t r e a t e d w i t h 65 ppm k i n o p r e n e (* --*) as newly-ecdysed a p t e r o u s a d u l t s . 45 f e c u n d i t y d e c l i n e d a b r u p t l y so t h a t by the end o f 10th day, mean f e c u n d i t y was 3.2 i n the t r e a t e d i n s e c t s and 3.3 i n the c o n t r o l s . (h) Apterous a d u l t s (alate-producers) To assess the p r e n a t a l e f f e c t s o f JH on wing de-velopment, kinoprene (65 ppm) was a p p l i e d t o apterous a d u l t s w i t h i n 12 h r s . o f t h e i r emergence. Twenty females were r e a r e d t o g e t h e r i n each cage. O f f s p r i n g were c o l l e c t e d d a i l y f o r 3 days and r e a r e d under crowded c o n d i t i o n s to favour the p r o d u c t i o n o f a l a t i f o r m s . In the c o n t r o l s , o n l y 10% of the o f f s p r i n g developed i n t o apterae (Table 7 ) . In c o n t r a s t , 76.6% of the o f f s p r i n g born to k i n o p r e n e - t r e a t e d i n s e c t s developed i n t o normal-looking apterous a d u l t s . The kinoprene-treatment had no e f f e c t on developmental times o f the o f f -s p r i n g as they emerged as a d u l t s a t the same time as the " c o n t r o l s . B. COMBINED EFFECTS OF PRECOCENE AND KINOPRENE (a) F i r s t and second i n s t a r a p t e r i f o r m nymphs of apterous  a d u l t s When 0.5 ug precocene-II was a p p l i e d t o p i c a l l y to f i r s t and second i n s t a r a p t e r i f o r m nymphs of apterous a d u l t s , no s i g n i f i c a n t l e t h a l e f f e c t s were apparent. However, e c d y s i s was delayed a t each subsequent nymphal stage as c o n t r o l aphids molted about 1 to lh days sooner than the p r e c o c e n e - t r e a t e d T a b l e 7. A p t e r a e p r o d u c t i o n by a p t e r o u s females which were t r e a t e d w i t h 65 ppm k i n o p r e n e w i t h i n 12 h r s . o f a d u l t emergence. Treatment Age o f mothers when l a r v a e c o l l e c t e d No. o f l a r v a e c o l l e c t e d No. o f l a r v a e m o l t i n g i n t o a p t e r o u s a d u l t s % a p t e r o u s a d u l t s produced C o n t r o l K i n o p r e n e 1-day-old 2 " 3 " 1-day-old 2 " 3 " 40 40 40 40 40 40 5 3 4 30 32 30 12.5 7.5 10. 0 ±=10.0 75. 0 80.0 75. 0 ±=76.6 CTl 47 i n s e c t s . A l t h o u g h a l l t h e l a t t e r i n s e c t s d e v e l o p e d i n t o n o r m a l - l o o k i n g a p t e r a e , t h e i r f e c u n d i t y was s i g n i f i c a n t l y l o w er t h a n i n t h e c o n t r o l s (Table 8 ) . D u r i n g th e f i r s t 10 days o f a d u l t l i f e , t h e c o n t r o l females produced an average o f 3.2 o f f s p r i n g / d a y whereas the p r e c o c e n e - t r e a t e d f e males produced o n l y 0.7 o f f s p r i n g / d a y . However, when k i n o p r e n e was a p p l i e d t o t h e s e i n s e c t s 4 days a f t e r a d u l t emergence, f e c u n d i t y i n c r e a s e d s i g n i f i c a n t l y b u t n ever r e a c h e d l e v e l s i n t h e c o n t r o l s (Table 8 ) . The d a i l y e f f e c t s o f p r e c o c e n e -I I and k i n o p r e n e on f e c u n d i t y a r e shown i n F i g s . 16 and 17. The s t i m u l a t o r y e f f e c t s o f k i n o p r e n e on f e c u n d i t y o f p r e c o c e n e - t r e a t e d f e males were n o t a p p a r e n t u n t i l 1 o r 2 days a f t e r t h e JHA had been a p p l i e d . F o l l o w i n g t h i s , t h e k i n o p r e n e -t r e a t e d f e males produced n e a r l y 2 o f f s p r i n g / d a y . By t h e 10th day, f e c u n d i t y was comparable t o t h a t o f t h e c o n t r o l s , (b) T h i r d and f o u r t h i n s t a r a p t e r i f o r m nymphs o f a p t e r o u s a d u l t s A l t h o u g h no s i g n i f i c a n t l e t h a l e f f e c t s were o b s e r v e d when p r e c o c e n e - I I was a p p l i e d t o t h i r d and f o u r t h i n s t a r a p t e r i f o r m nymphs, e c d y s i s was d e l a y e d f o r about 7 o r 8 h r s . a t each subsequent nymphal m o l t . A l l t h e t r e a t e d nymphs de-v e l o p e d i n t o n o r m a l - l o o k i n g a p t e r a e . However, t h e i r f e c u n d i t y was s i g n i f i c a n t l y l o wer t h a n th e c o n t r o l s b u t h i g h e r t h a n p r e c o c e n e - t r e a t e d f i r s t and second i n s t a r s ( T a b l e 8 ) . Over a 10-day p e r i o d , females i n c o n t r o l and t r e a t e d groups p r o -T a b l e 8. E f f e c t s o f t o p i c a l a p p l i c a t i o n o f p r e c o c e n e - I I on t h e f e c u n d i t y o f a p t e r i f o r m nymphs o f a p t e r o u s a d u l t s . E xcept on a p t e r o u s a d u l t s , k i n o p r e n e was a p p l i e d t o t h e p r e c o c e n e - t r e a t e d i n s e c t s f o u r days a f t e r a d u l t emergence (5-6 r e p l i c a t e s / t r e a t m e n t , one i n s e c t / r e p l i c a t e ) * . Stage o f precocene a p p l i c a t i o n Average f e c u n d i t y / s u r v i v i n g female/day C o n t r o l P r e c o c e n e - t r e a t e d P r e c o c e n e - k i n o p r e n e t r e a t e d 1 s t i n s t a r 2nd i n s t a r 3 r d i n s t a r 4 t h i n s t a r A p t e r o u s a d u l t s 3, 3, 3, 3, 3, 2±0.0 C 2±0.1' 2±0.1 £ 2±0. 0e 2+0.0 £ 0.7±0.0 0 . 7 - i O . O 1 1.8±0.2* 2.5±0.01 0 . 6 ± 0 . 1 * 1.2±0.1 1.4±0.0( 2.3+0.1C 2.7 + 0.0* 1.7±0. 0C 2.5±0.0 d**. * Mean d i f f e r e n c e s a t 5% l e v e l u s i n g Duncan's M u l t i p l e Range t e s t * *Kinoprene a p p l i e d 24 h r s . a f t e r a d u l t emergence. CO 5 1 2 3 4 5 6 7 8 9 Age (days) F i g u r e 16. F e c u n d i t y o f c o n t r o l a p h i d s (• • ) and t h o s e t r e a t e d w i t h 0.5 ug p r e c o c e n e - I I (-- -) as f i r s t i n s t a r a p t e r i f o r m nymphs o f a p t e r o u s a d u l t s . The e f f e c t s o f 10 ppm k i n o p r e n e ( o — — — — — o ) a p p l i e d t o p r e c o c e n e - t r e a t e d i n s e c t s f o u r days a f t e r a d u l t emergence are a l s o i n d i c a t e d . Age (days) F i g u r e 17. F e c u n d i t y o f c o n t r o l a p h i d s (• • ) and t h o s e t r e a t e d w i t h 0.5 ug p r e c o c e n e - I I (- -) as second i n s t a r a p t e r i f o r m nymphs o f a p t e r o u s a d u l t s . The e f f e c t s o f 10 ppm k i n o p r e n e (o o) a p p l i e d t o p r e c o c e n e - t r e a t e d i n s e c t s f o u r days a f t e r a d u l t emergence a r e a l s o i n d i c a t e d . 51 duced an average o f 3.2 and 1.5-2.5 o f f s p r i n g / d a y , r e s p e c t i v e l y . K i n o p r e n e a p p l i c a t i o n t o p r e c o c e n e - t r e a t e d i n s e c t s on t h e i r 4 t h day o f a d u l t l i f e i n c r e a s e d f e c u n d i t y s i g n i f i c a n t l y . The f e c u n d i t y o f emergent t h i r d i n s t a r s was s i g n i f i c a n t l y l o w e r t h a n i n t h e c o n t r o l s whereas t h e f e c u n d i t y o f t h e emergent f o u r t h i n s t a r s was comparable t o t h e c o n t r o l s (Table 8 ) . The d a i l y e f f e c t s o f p r e c o c e n e - I I and k i n o p r e n e on t h e f e c u n d i t y o f t h e two i n s t a r s a r e shown i n F i g s . 18-19. Kinop r e n e ap-p l i c a t i o n r e s u l t e d i n an immediate i n c r e a s e i n f e c u n d i t y o f b o t h i n s t a r s . (c) A p t e r o u s a d u l t s When 0.2 ug p r e c o c e n e - I I was a p p l i e d t o newly-ecdysed a p t e r o u s a d u l t s , f e c u n d i t y was s i g n i f i c a n t l y reduced (Table 8 ) . Compared t o t h e c o n t r o l f e m a l e s , w h i c h produced an average o f 3.2 o f f s p r i n g / d a y , t h e p r e c o c e n e - t r e a t e d females produced 0.8 o f f s p r i n g d a i l y . When k i n o p r e n e was a p p l i e d t o t h e s e i n s e c t s 24 h r s . a f t e r t h e i r a d u l t emergence, t h e e f f e c t s on r e p r o d u c t i o n were n ot ap p a r e n t u n t i l 3 days l a t e r , ( F i g . 2 0 ) . However, a f t e r t h i s , f e c u n d i t y i n c r e a s e d s h a r p l y so t h a t by t h e 7 t h day, i t was comparable t o t h e c o n t r o l s . K i n o p r e n e a p p l i c a t i o n t o 4-day-old p r e c o c e n e -t r e a t e d a d u l t s a l s o c o n t r i b u t e d t o a d e l a y e d b u t pronounced i n c r e a s e i n f e c u n d i t y . 1 2 3 4 5 6 7 8 9 1 0 Age (days) F i g u r e 18. F e c u n d i t y o f c o n t r o l a p h i d s (• -•) and t h o s e t r e a t e d w i t h 0.5 ug p r e c o c e n e - I I (- -*) as t h i r d i n s t a r a p t e r i f o r m nymphs o f a p t e r o u s a d u l t s . The e f f e c t s o f 10 ppm k i n o p r e n e (o o) a p p l i e d t o p r e c o c e n e - t r e a t e d i n s e c t s f o u r days a f t e r a d u l t emergence a r e a l s o i n d i c a t e d . j I I 1 1 1 1 ! 1 1 2 3 4 5 6 7 8 9 1 0 Age (days) gure 19. F e c u n d i t y o f c o n t r o l a p h i d s (• e) and t h o s e t r e a t e d w i t h 0.5 ug p r e c o c e n e - I I A) as f o u r t h i n s t a r a p t e r i f o r m nymphs o f a p t e r o u s a d u l t s . The e f f e c t s o f 10 ppm k i n o p r e n e (o o) a p p l i e d t o p r e c o c e n e - t r e a t e d i n s e c t s f o u r days a f t e r a d u l t emergence are a l s o i n d i c a t e d . P -d H CD O F e c u n d i t y ( o f f s p r i n g / f e m a l e / d a y ) r t OJ 3 r t •CS CD CD O O o OJ CD OJ d H i 13 P J _ ) r t CD d CD I H r t H. OJ CD Ch 0) d r t M CD r t CD 3 M 1 3 r t hi cn CD • o O O. t-3 CD ch ty 3 CD CD P - I CD H CD O d 3 Ch p-r t O H i o o 3 r t H O -1 O CD 3 O CD r t O cn l i -en d - O H i | i-i o\ \ cn u i H 13 .13 OJ 3 cn cn O P -3 Ch p-o *T 3 P - CD 3 £ O M 13 ^ OJ — - P, I r t CD CD CD O 3 O Ch hj CD Ch OJ cn 13 CD £—13 S—> OJ H ^ p . cn CD Ch 0) 3 C-r t tr o cn CD r t H CD OJ r t CD Ch CO -1 CD 0) Ti CD cn H I - H 3" — H ro H I p -CD — P J cn Ch 0J K : cn 0 3 O L I O -r— C O Ol 55 (d) Apteriform nymphs of alate adults Experiments performed with precocene-II and kino-prene on the f i r s t and second i n s t a r apteriform nymphs of alate adults produced more or less the same res u l t s as with apteriform nymphs of apterous adults. No s i g n i f i c a n t d i f -ference in l e t h a l i t y was observed between the treated and control insects. However, ecdysis was again delayed at each subsequent nymphal stage i n a l l the treated insects. A l -though a l l the precocene-treated insects developed into normal looking apterae, th e i r fecundity was s i g n i f i c a n t l y reduced compared to the controls (Table 9). Mean d a i l y fecundity observed during the f i r s t 10 days of adult l i f e ranged from 2.2 to 3.0 i n the controls and from 0.8 to 2.0 in the treated aphids. When kinoprene was applied to these insects 4 days after t h e i r adult emergence, fecundity increased s i g n i f i c a n t l y . However, fecundity never reached the le v e l s of controls i n the emergent JHA-treated f i r s t and second ins t a r s (Figs. 21-22). In treated t h i r d and fourth i n s t a r s , i t was equivalent to that of controls by the 5th-7th day of adult emergence (Figs. 23-24). T a b l e 9. E f f e c t s o f t o p i c a l a p p l i c a t i o n o f p r e c o c e n e - I I on t h e f e c u n d i t y o f a p t e r i f o r m nymphs o f a l a t e a d u l t s . Kinoprene was a p p l i e d t o t h e 4? p r e c o c e n e - t r e a t e d i n s e c t s f o u r days a f t e r a d u l t emergence (5-6 r e p l i c a t e s / t r e a t m e n t , one i n s e c t / r e p l i c a t e ) * Average f e c u n d i t y / s u r v i v i n g female/day C o n t r o l P r e c o c e n e - t r e a t e d P r e c o c e n e - k i n o p r e n e t r e a t e d Stage o f precocene a p p l i c a t i o n 1 s t i n s t a r 2.7±0.0 a 0.8±0.0 b 1.1±0.0 C 2nd i n s t a r 3.0±0.1 a 0.8+0.1 b 1.3±0.0 C 3 r d i n s t a r 2.8±0.1 a 1.5±0.2 b 2.6+0.0 a 4 t h i n s t a r 3.0+0.1 a 2.0±0.7 b 1.5±0.1 C * Mean d i f f e r e n c e s a t 5% l e v e l u s i n g Duncan's M u l t i p l e Range t e s t 5 1 2 3 4 5 6 7 8 9 1 0 Age (days) F i g u r e 21. F e c u n d i t y o f c o n t r o l a p h i d s (• •) and t h o s e t r e a t e d w i t h 0.5 ug p r e c o c e n e - I I (* ±) as f i r s t i n s t a r nymphs o f a l a t e a d u l t s . The e f f e c t s o f 10 ppm k i n o p r e n e (o o) a p p l i e d t o p r e c o c e n e - t r e a t e d i n s e c t s f o u r days a f t e r a d u l t emergence are a l s o i n d i c a t e d . 5T Age (days) F i g u r e 22. F e c u n d i t y o f c o n t r o l a p h i d s (•-———•) and those t r e a t e d w i t h 0.5 ug p r e c o c e n e - I I *•) as. second i n s t a r a p t e r i f o r m nymphs of a l a t e a d u l t s . The e f f e c t s o f 10 ppm k i n o p r e n e (o o) a p p l i e d t o p r e c o c e n e - t r e a t e d i n s e c t s f o u r days a f t e r a d u l t emergence are a l s o i n d i c a t e d . co 5 6 Age (days) 8 F i g u r e 23. F e c u n d i t y o f c o n t r o l a p h i d s (• •) and those t r e a t e d w i t h 0.5 ug p r e c o c e n e - I I (* *) as t h i r d i n s t a r a p t e r i f o r m nymphs o f a l a t e a d u l t s . The e f f e c t s o f 10 ppm k i n o p r e n e (o o) a p p l i e d t o p r e c o c e n e - t r e a t e d i n s e c t s f o u r days a f t e r a d u l t emergence are a l s o i n d i c a t e d . CD 4 5 6 Age (days) 8 1 0 F i g u r e 24. F e c u n d i t y o f c o n t r o l a p h i d s (• •) and those t r e a t e d w i t h 0.5 ug p r e c o c e n e - I I --) as f o u r t h i n s t a r a p t e r i f o r m nymphs o f a l a t e a d u l t s . The e f f e c t s o f 10 ppm k i n o p r e n e (o o) a p p l i e d t o p r e c o c e n e - t r e a t e d i n s e c t s f o u r days a f t e r a d u l t emergence are a l s o i n d i c a t e d . cn o 61 DISCUSSION A. POLYMORPHISM IN THE GREEN PEACH APHID Although polymorphism i n aphids i s known to be i n f l u e n c e d by a v a r i e t y of environmental s t i m u l i (Lees 1966, H i l l e R i s Lambers 1966), the p h y s i o l o g i c a l mechanisms which c o n t r o l morph d e t e r m i n a t i o n are p o o r l y understood. In the c u r r e n t study, c o l o n i e s o f M^ p e r s i c a e were exposed to l o n g -day c o n d i t i o n s to promote the e x c l u s i v e p r o d u c t i o n of a d u l t v i r g i n o p a r a e which are p a r t h e n o g e n e t i c and v i v i p a r o u s . In a d d i t i o n , a d u l t v i r g i n o p a r a e and t h e i r o f f s p r i n g were r e a r e d under e i t h e r i s o l a t e d c o n d i t i o n s to favour the p r o d u c t i o n of apterous morphs or crowded c o n d i t i o n s to promote formation of a l a t e s . In the l a t t e r i n s t a n c e , the response of apterous v i r g i n o p a r a e to crowding was not a b s o l u t e as n e a r l y 10% of the progeny, which were a l s o maintained under crowded con-d i t i o n s , developed i n t o apterae. In M^ v i c i a e , where maternal crowding has been shown to favour a l a t e p r o d u c t i o n , v a r i a b l e p r o p o r t i o n s of a l a t e s are a l s o produced (Lees 1967, 1980). However, i n t h i s s p e c i e s , many apterous v i r g i n o p a r a e respond to crowding by producing e x c l u s i v e l y a l a t e o f f s p r i n g . Although t h i s suggests t h a t M^ v i c i a e i s more s e n s i t i v e to crowding than M^_ p e r s i c a e , somewhat d i f f e r e n t techniques were employed to simulate crowded c o n d i t i o n s . In the p r e s e n t study, these 62 c o n d i t i o n s were c r e a t e d by t r a n s f e r r i n g 25 a p t e r o u s v i r g i n o -parae i n t o c l i p - c a g e s a t t a c h e d t o C h i n e s e cabbage p l a n t s ; whereas, i n t h e i n v e s t i g a t i o n s o f Lees (1967, 1980), 10 a d u l t s were t r a n s f e r r e d i n t o specimen t u b e s , crowded f o r 24 h r s . , then r e t u r n e d t o bean p l a n t s . T h e r e f o r e , th e h i g h f r e -quency o f a l a t e f o r m a t i o n i n v i c i a e may be a t t r i b u t e d t o n o t o n l y c rowding but a l s o temporary s t a r v a t i o n . I n p e r s i c a e , s e v e r a l m o r p h o l o g i c a l c r i t e r i a can be used t o d i s t i n g u i s h between the a l a t e and a p t e r o u s morphs. These d i f f e r e n c e s f i r s t become a p p a r e n t i n t h e t h i r d i n s t a r when wing buds become v i s i b l e e x t e r n a l l y i n p r e s u m p t i v e a l a t e s . The a p t e r o u s nymphs ar e somewhat more g l o b u l a r i n appearance and l a c k s w e l l i n g s i n t h e p r o t h o r a x a s s o c i a t e d w i t h t h e development of f l i g h t m uscles i n a l a t e s . E x c e p t f o r a p o i n t e d cauda and e n l a r g e d g e n i t a l p l a t e , a d u l t a p t e r a e undergo l i t t l e metamorphosis and r e t a i n many nymphal c h a r a c t e r i s t i c s . These i n c l u d e an unpigmented body, reduced t h o r a c i c s c l e r o t i z a t i o n a n d t h e absence of o c e l l i . I n c o n t r a s t , metamorphic changes a r e v e r y pronounced i n a l a t e s and appear t o complement wing development. Fo r example, t h e c u t i c l e becomes d a r k l y pigmented and h e a v i l y s c l e r o t i z e d p a r t i c u l a r l y i n the t h o r a x . T h i s s c l e r o t i z a t i o n r e p r e s e n t s an i m p o r t a n t a d a p t a t i o n t o f l i g h t . The s c l e r o t i -z a t i o n p r o c e s s i s known t o i n v o l v e t h e f o r m a t i o n o f c o v a l e n t bonds between N - a c e t y l dopamine and p r o t e i n s i n t h e e x o c u t i c l e 63 (Chapman 1975). As a r e s u l t , the t h o r a c i c c u t i c l e i s r e n d e r e d s t r o n g e r and b e t t e r a b l e t o s u p p o r t c o n t r a c t i o n s o f the f l i g h t m u s c l e s . O c e l l i and secondary a n t e n n a l s e n s o r i a a r e a l s o p r e s e n t i n a d u l t a l a t e s . A l t h o u g h t h e i r i m p o r t a n c e i n f l i g h t i s d e b a t a b l e , t h e s e s e n s o r y organs a r e b e l i e v e d t o s e r v e as photo and chemoreceptors and may be i m p o r t a n t i n f l i g h t n a v i g a t i o n and h o s t - p l a n t l o c a t i o n ( W e l l i n g t o n 1974; Goodman 1975; Bromley e t a l . 1979) . I n most hemimetabolous and paurometabolous i n s e c t s , nymphal development, metamorphosis and r e p r o d u c t i o n a r e s e p a r a t e d t e m p o r a l l y (Chapman 1975). However, i n a p t e r o u s and a l a t e v i r g i n o p a r a e , l a r v i p o s i t i o n u s u a l l y b e g i n s on the f i r s t day o f a d u l t l i f e . As i t i s i n c o n c e i v a b l e t h a t o o c y t e d e v e l o p -ment and embryogenesis c o u l d o c c u r i n one day, i t i s a p p a r e n t t h a t r e p r o d u c t i v e development b e g i n s i n t h e nymphal s t a g e s . A l t h o u g h t h e s i m u l t a n e o u s development o f the mother and her o f f s p r i n g would s h o r t e n t h e g e n e r a t i o n t i m e and f a v o u r r a p i d p o p u l a t i o n i n c r e a s e s , the phenomenon p r e s e n t s a c h a l l e n g e t o p h y s i o l o g i s t s t o e x p l a i n how such development i s c o o r d i n a t e d . The s i t u a t i o n becomes even more c o m p l i c a t e d when the morphology o f t h e o f f s p r i n g d i f f e r s from t h a t o f t h e mother. 64 B. ROLE OF JUVENILE HORMONE (JH) As d e s c r i b e d i n the I n t r o d u c t i o n , some i n v e s t i g a t o r s b e l i e v e t h a t JH p l a y s an important r o l e i n a p h i d morphogenesis and polymorphism. Basing t h e i r c o n c l u s i o n s s o l e l y on the h i s t o l o g i c a l appearance of the corpora a l l a t a (CA), White (1965, 1968b) and E l l i o t t (1975) suggested t h a t h i g h l e v e l s o f JH i n a p t e r i f o r m nymphs favoured the r e t e n t i o n o f j u v e n i l e c h a r a c t e r i s t i c s and i n h i b i t e d wing development. They a l s o p o s t u l a t e d t h a t JH t i t e r s d e c l i n e d i n apterous a d u l t s but i n c r e a s e d i n a l a t e a d u l t s . T h i s would e x p l a i n why a l a t e s i n v a r i a b l y produce apterous o f f s p r i n g . The u l t r a s t r u c t u r a l s t u d i e s of L e c k s t e i n (1976) c h a l l e n g e d these hypotheses and suggested t h a t v o l u m e t r i c changes i n the CA are not i n d i c a t i v e of g l a n d u l a r a c t i v i t y and JH s y n t h e s i s . Moreover, numerous s t u d i e s , which have examined the g r o w t h - r e g u l a t i n g p r o p e r t i e s of JHA i n v a r i o u s a p h i d s p e c i e s , p r o v i d e no c l e a r i n d i c a t i o n o f the r o l e o f JH i n a p h i d morphogenesis and r e p r o d u c t i o n . In an attempt to r e s o l v e the c o n t r o v e r s y surrounding the r o l e of JH, kinoprene and/or precocene were a p p l i e d t o p i c a l l y to the v a r i o u s stages of a l a t e and apterous morphs o f p e r s i c a e . The c h o i c e o f kinoprene over other JHA has proven advantageous because the analogue has r e c e n t l y been shown to be as b i o l o g i c a l l y a c t i v e i n aphids as JHI, a n a t u r a l l y - o c c u r r i n g form of the hormone (Lees 1980). Furthermore, as w i l l become 65 e v i d e n t s h o r t l y , the a p p l i c a t i o n methods employed i n t h i s study have advantages over o t h e r b i o a s s a y methods ( i e . JHA-t r e a t e d f o l i a g e or a r t i f i c i a l d i e t s ) i n t h a t the p o t e n t i a l r o l e of JH i n the i n d i v i d u a l stages can be e v a l u a t e d , (a) Reproduction In other i n s e c t s , a l l a t e c t o m y or precocene t r e a t -ment i n h i b i t s o v a r i a n development (Engelmann 1970; G i l b e r t 1976). Since t h i s i n h i b i t i o n can be r e v e r s e d by t o p i c a l JHA treatment, i t has been e s t a b l i s h e d t h a t JH s t i m u l a t e s y o l k d e p o s i t i o n i n the d e v e l o p i n g oocytes. In aphid s p e c i e s , the r o l e of JH i n r e p r o d u c t i o n remains u n c e r t a i n . In A^ fabae, the r e p r o d u c t i v e r a t e of apterous a d u l t s r e a r e d on JHA-treated p l a n t s f o r 48 h r s . was not s i g n i f i c a n t l y d i f f e r e n t from t h a t of a d u l t s r e a r e d on u n t r e a t e d f o l i a g e (Hangartner e t ajL. 1971) . Although t h i s would appear to i n d i c a t e t h a t JH has no i n f l u e n c e on r e p r o d u c t i o n or i s not a l i m i t i n g f a c t o r i n apterous a d u l t s , the d i r e c t e f f e c t s o f JH on r e p r o d u c t i o n are u n c l e a r because the analogue used i n t h i s study was a l s o h i g h l y r e p e l l e n t and t o x i c to the female aphids (Hangartner e t a l . 1971). Using s i m i l a r techniques, M i t t l e r e t a l . (1976) r e a r e d f o u r t h i n s t a r gynoparae and v i r g i n o p a r a e of A^ fabae and p e r s i c a e on p l a n t s t r e a t e d with 0.1% kinoprene. During the three-week o b s e r v a t i o n p e r i o d , the t o t a l number of progeny produced by the t r e a t e d and c o n t r o l groups d i d not d i f f e r g r e a t l y . However, 66 d u r i n g the f i r s t few days o f a d u l t l i f e , l a r v i p o s i t i o n was i n i t i a t e d sooner and o c c u r r e d a t a f a s t e r r a t e i n the k i n o p r e n e - t r e a t e d aphids than .in the c o n t r o l s . M i t t l e r e t a l . (1976) suggested t h a t JH may s t i m u l a t e o v a r i a n development and embryogenesis i n both s p e c i e s . The authors a l s o specu-l a t e d t h a t CA a c t i v i t y i n the nymphs might a l s o i n h i b i t the formation o f c e r t a i n a l a t e c h a r a c t e r i s t i c s , n o t a b l y the f l i g h t muscles. T h i s i n h i b i t i o n would e x p l a i n why more embryos develop i n the o v a r i o l e s o f a p t e r i f o r m nymphs than those of a l a t i f o r m s . Furthermore, M i t t l e r e t a_l. suggested t h a t the slow r e p r o d u c t i v e maturation of nymphal gynoparae may r e s u l t from the p r o d u c t i o n of l e s s JH or gonadotropic hormone. A comparable gonadotropic r o l e o f the CA was not demonstrated i n A^ pisum (MacKauer e t a_l. 1979) . In t h i s s p e c i e s , t o p i c a l a p p l i c a t i o n o f 1.0 ug precocene-II ( d i s s o l v e d i n acetone) t o 3- to 5 - h r . - o l d apterous v i r g i n o p a r a e r e s u l t e d i n 63% m o r t a l i -t y . Although a smal l d e c l i n e was observed i n the number of o f f s p r i n g produced by the s u r v i v o r s , no s t e r i l a n t e f f e c t s were apparent. In M^ p e r s i c a e , t o p i c a l a p p l i c a t i o n o f 0.5 ug precocene-II ( d i s s o l v e d i n DMSO) to apterous v i r g i n o p a r a e w i t h i n 2 to 3 h r s . of t h e i r emergence r e s u l t e d i n no a d u l t m o r t a l i t y but induced almost complete s t e r i l i t y . Each t r e a t e d female produced o n l y one o f f s p r i n g / d a y but the nymphs d i e d 67 w i t h i n 24 h r s . o f b i r t h . I n o r d e r t o a v o i d t h e s e t o x i c e f f e c t s , t h e precocene dosage was re d u c e d t o 0.2 ug / a p h i d . A t t h i s dosage, l a r v i p o s i t i o n d e c l i n e d a l m o s t i m m e d i a t e l y . One day a f t e r a p p l i c a t i o n , t h e p r e c o c e n e - t r e a t e d females produced o n l y one o f f s p r i n g / d a y whereas t h e c o n t r o l s p r o -duced t h r e e t o f o u r o f f s p r i n g d a i l y . Reduced l a r v i p o s i t i o n i n t h e p r e c o c e n e - t r e a t e d females c o n t i n u e d f o r a t l e a s t 10 days. However, the i n h i b i t o r y e f f e c t s o f precocene were r e v e r s e d when t h e females were t r e a t e d w i t h 65 ppm k i n o p r e n e . K i n o p r e n e was more s t i m u l a t o r y t o l a r v i p o s i t i o n when i t a p p l i e d w i t h i n 24 h r s . o f t h e precocene t r e a t m e n t t h a n when i t was a p p l i e d 4 days a f t e r the precocene t r e a t m e n t . I n b o t h i n s t a n c e s , an i n c r e a s e i n l a r v i p o s i t i o n was n o t e v i d e n t f o r a t l e a s t 2 days a f t e r k i n o p r e n e was a p p l i e d . Comparable e f f e c t s were o b s e r v e d when 0.5 ug p r e c o c e n e - I I was a p p l i e d t o f i r s t and second i n s t a r a p t e r i f o r m nymphs o f a p t e r o u s o r a l a t e v i r g i n o p a r a e . A f t e r t h e nymphs had emerged as a d u l t s , t h e y produced l e s s t h a n one o f f p s p r i n g / d a y b u t when t r e a t e d w i t h k i n o p r e n e , l a r v i p o s i t i o n r a t e s d o u b l e d a f t e r 1 o r 2 days. I n c o n t r a s t , precocene t r e a t m e n t s a p p l i e d t o t h i r d and f o u r t h i n s t a r a p t e r i f o r m nymphs o f a p t e r o u s o r a l a t e a d u l t s were l e s s i n h i b i t o r y . A l t h o u g h t h e t r e a t e d i n s e c t s produced s i g n i f i c a n t l y fewer o f f s p r i n g t h a n the c o n t r o l s , l a r v i p o s i t i o n r a t e s were two o r t h r e e t i m e s h i g h e r than t h o s e o f a d u l t s 68 which had been t r e a t e d w i t h precocene as f i r s t o r second i n s t a r nymphs. In a d d i t i o n , kinoprene a p p l i c a t i o n to a d u l t s which had been t r e a t e d w i t h precocene as t h i r d and f o u r t h i n s t a r s i n c r e a s e d l a r v i p o s i t i o n r a t e s to l e v e l s comparable to those o f the c o n t r o l s . C o l l e c t i v e l y , the r e s u l t s demonstrate t h a t JH p l a y s an important r o l e i n r e p r o d u c t i o n i n apterous green peach aphids. They a l s o i n d i c a t e t h a t i f the apterous morphs are to a t t a i n normal r e p r o d u c t i v e l e v e l s , the CA must be a c t i v e i n a l l stages. However, the a c t i v i t y o f the CA appears to vary from stage to stage. As observed i n o t h e r s p e c i e s (Unnithan and N a i r 1979), the f i n a l nymphal i n s t a r was the l e a s t s e n s i t i v e to precocene. To account f o r t h i s low s e n s i -t i v i t y , Unnithan and N a i r (1979) suggested t h a t precocene e x e r t s an a n t i - a l l a t o t r o p i c e f f e c t o n l y when the CA are a c t i v e . I f t h i s h y p o t h e s i s i s t e n a b l e i n p e r s i c a e , the CA o f t h i r d and p a r t i c u l a r l y f o u r t h i n s t a r a p t e r i f o r m s are r e l a t i v e l y i n a c t i v e whereas the CA of f i r s t and second i n s t a r s and a d u l t s are very a c t i v e . Although a d d i t i o n a l evidence w i l l be presented to support these c o n c l u s i o n s , the subsequent s t u d i e s i n d i c a t e t h a t the CA i n a l a t i f o r m nymphs e x h i b i t a d i f f e r e n t p a t t e r n o f a c t i v i t y . (b) M o u l t i n g and metamorphosis In exopterygotes, p r o g r e s s i v e m o r p h o l o g i c a l changes 69 which occur d u r i n g moulting and metamorphosis are mediated hormonally (Wigglesworth 1970; Chapman 1975; G i l b e r t 1975) . In c o n j u n c t i o n w i t h the moulting hormone, ecdysone, JH has been shown t o programme the epidermal c e l l s to produce a p a r t i c u l a r type o f c u t i c l e p r i o r t o each moult. The i n v o l v e -ment o f JH i n the programming of the epidermal c e l l s has been demonstrated by a v a r i e t y o f s u r g i c a l and chemical techniques. For example, a l l a t e c t o m y or precocene treatments performed on penultimate or young nymphal i n s t a r s induced p r e c o c i o u s metamorphosis and premature development of a d u l t c h a r a c t e r i s t i c s . C onversely, CA implants or JHA treatments a d m i n i s t e r e d to nymphal stages delay or prevent metamorphosis. Depending upon the a c t i v i t y of the JHA, i t s dosage and when i t i s a p p l i e d , the t r e a t e d i n s e c t s may e x h i b i t j u v e n i l e and/ or a d u l t c h a r a c t e r i s t i c s . From these s t u d i e s , i t has been hypothesized t h a t when JH i s p r e s e n t a t the i n i t i a t i o n o f each moulting c y c l e , the i n s e c t develops i n t o an immature form. However, when JH i s absent d u r i n g the c r i t i c a l p e r i o d , the i n s e c t develops i n t o an a d u l t . Thus, i n normal i n s e c t s , the occurrence of metamorphosis i s a t t r i b u t e d t o a p r e c i p i -tous d e c l i n e i n JH t i t e r d u r i n g the f i n a l i n s t a r . As d i s c u s s e d p r e v i o u s l y the developmental p a t t e r n e x h i b i t e d by most i n s e c t s p e c i e s i s more e v i d e n t i n a l a t e than apterous morphs. I f the hormonal mechanisms c o n t r o l l i n g 70 m o u l t i n g and metamorphosis i n a p h i d s a r e s i m i l a r t o t h a t o f o t h e r e x o p t e r y g o t e s , a p t e r i f o r m nymphs s h o u l d be c h a r a c t e r i z e d by h i g h e r JH l e v e l s t h a n a l a t i f o r m nymphs. As r e p o r t e d i n many a p h i d s p e c i e s , (Lees 1966, 1977, 1980; Hangartner e t a l . 1971; Hrdy 1974; C l o u t i e r and P e r r o n 1975; M i t t l e r e t a l . 1976) , a l a t i f o r m nymphs o f M_^_ p e r s i c a e t r e a t e d w i t h JHA de v e l o p i n t o l a r v a l - a d u l t i n t e r m e d i a t e s . The degree o f j u v e n i l i z a t i o n e x h i b i t e d by t h e emergent a d u l t depended upon when the k i n o p r e n e was a p p l i e d . U n l i k e M^ v i c i a e where t h e most J H A - s e n s i t i v e s t a g e was the t h i r d . i n s t a r a l a t i f o r m nymph (Lees 19 80), the development o f f i r s t and second' i n s t a r a l a t i f o r m s o f ML_ p e r s i c a e was d r a s t i c a l l y a l t e r e d by t o p i c a l a p p l i c a t i o n s o f 65 ppm k i n o p r e n e . Over 80% o f t h e t r e a t e d i n s e c t s underwent a supernumerary m o u l t b e f o r e de-v e l o p i n g i n t o a d u l t s . A p a r t from the p r e s e n c e o f s m a l l wing buds, t h e a d u l t s were a l m o s t i n d i s t i n g u i s h a b l e from a p t e r o u s a d u l t s . F u r t h e r m o r e , t h e i n s e c t s l a c k e d a p o i n t e d cauda and had an underdeveloped g e n i t a l p l a t e . As b o t h f e a t u r e s a r e found i n a p t e r o u s and a l a t e v i r g i n o p a r a e , the k i n o p r e n e -tr^a't'ed i n s e c t s a l s o e x h i b i t e d ;||afval^.chaKac,feer.isteics../.-Over 80% o f the t h i r d i n s t a r a l a t i f o r m nymphs t r e a t e d w i t h k i n o p r e n e underwent a supernumerary moult b u t d e v e l o p e d i n t o a d u l t s w i t h many a l a t e c h a r a c t e r i s t i c s . The f o u r t h i n s t a r was the l e a s t s e n s i t i v e s t a g e as v i r t u a l l y a l l the t r e a t e d 71 i n s e c t s developed i n t o normal-looking a l a t e v i r g i n o p a r a e . When 65 ppm kinoprene was a p p l i e d to comparable stages o f a p t e r i f o r m nymphs, 90% m o r t a l i t y o c c u r r e d w i t h i n 24 h r s . of treatment. Although the reasons f o r t h i s w i l l be d i s c u s s e d i n a l a t e r s e c t i o n , i t should be noted t h a t 10 ppm kinoprene caused no supernumerary moulting or d e v i a t i o n s from normal development. These r e s u l t s c l e a r l y demonstrate t h a t kinoprene can be used as JH mimic to a l t e r the normal programming o f the epidermal c e l l s i n a l a t i f o r m nymphs. Under the i n f l u e n c e of a r t i f i c i a l l y e l e v a t e d JH t i t e r s , the c e l l s were induced to form a c u t i c l e which was more j u v e n i l e or apterous i n ap-pearance. T h e r e f o r e , the f i n d i n g s support the g e n e r a l hypo-t h e s i s of White (1968b) and E l l i o t t (1975) t h a t a l a t i f o r m development occurs i n the presence o f low JH l e v e l s . F u r t h e r -more, the d i f f e r e n t i a l responses of the f o u r a l a t i f o r m i n s t a r s t o kinoprene suggest t h a t e l e v a t e d JH l e v e l s d u r i n g the f i r s t and second i n s t a r s are p a r t i c u l a r l y important i n i n h i b i t i n g the development of a l a t e f e a t u r e s and f a v o u r i n g the r e t e n t i o n o f apterous c h a r a c t e r i s t i c s . A d d i t i o n a l f i n d i n g s i n p e r s i c a e appear d i a -m e t r i c a l l y opposed to those o b t a i n e d i n other exopterygotes (Wigglesworth 1970; G i l b e r t 1975). In the l a t t e r s p e c i e s , the f i n a l nymphal i n s t a r i s u s u a l l y the most J H A - s e n s i t i v e 72 s t a g e . However, i n v i c i a e (Lees 1980) and p e r s i c a e , the f i n a l f o u r t h nymphal i n s t a r was a l m o s t t o t a l l y i n s e n s i t i v e t o k i n o p r e n e as t h e t r e a t e d nymphs d e v e l o p e d i n t o a p p a r e n t l y normal a l a t e a d u l t s . T h i s s u g g e s t s t h a t a d e c l i n e i n JH l e v e l s d u r i n g t h e l a s t nymphal i n s t a r i s n o t p r e r e q u i s i t e t o metamorphosis i n a l a t i f o r m a p h i d s . I n an at t e m p t t o e x p l a i n t h e anomalous response o f a p h i d s t o JHA, Lees (19 80) proposed t h a t (1) a d u l t d e t e r m i n a t i o n i s v i r t u a l l y complete by the f i r s t day o f t h e l a s t i n s t a r and (2) more i m p o r t a n t l y , t i s s u e s i n f o u r t h i n s t a r a re i n s e n s i t i v e t o JH. Lees c l a i m e d t h a t t h i s r e p r e s e n t e d an a d a p t a t i o n i n a p h i d s w h i c h p e r m i t t e d JH t o r e g u l a t e b o t h metamorphosis and polymorphism by s e p a r a t i n g t h e s e f u n c t i o n s i n t i m e . The f l a w i n t h e Lees' h y p o t h e s i s i s t h a t t h e e p i d e r m a l c e l l s i n the f o u r t h i n s t a r f L p e r s i c a e a r e o b v i o u s l y J H - s e n s i t i v e because when k i n o p r e n e was a p p l i e d t o e a r l i e r i n s t a r s , t h e c e l l s were re-programmed t o produce an a d d i t i o n a l l a r v a l c u t i c l e and undergo a supernumerary moult b e f o r e p r o d u c i n g an a d u l t o i d c u t i c l e . T h e r e f o r e , a more l i k e l y e x p l a n a t i o n can be proposed t o e x p l a i n t h e ap p a r e n t i n s e n s i t i v i t y o f t i s s u e s i n t h e f o u r t h i n s t a r t o k i n o p r e n e . I n the r e p r o d u c t i o n s t u d i e s , k i n o p r e n e s i g n i f i c a n t l y i n c r e a s e d l a r v i p o s i t i o n r a t e s o f p r e c o c e n e - t r e a t e d v i r g i n o p a r a e . However, t h i s i n c r e a s e was n o t immediate b u t r a t h e r o c c u r r e d 1 t o 2 days a f t e r k i n o p r e n e was a p p l i e d . T h i s d e l a y may r e p r e s e n t 73 t h e t i m e r e q u i r e d f o r k i n o p r e n e t o d i f f u s e t h r o u g h th e c u t i c l e and r e a c h s u f f i c i e n t l e v e l s t o s t i m u l a t e t h e t a r g e t t i s s u e s . I n f o u r t h i n s t a r a l a t i f o r m s o f v i c i a e (Lees 1980) and M. p e r s i c a e , t h i s d e l a y would be c r i t i c a l as t h e f o u r t h s t a d i u m l a s t s 2 t o 3 days. T h e r e f o r e , by t h e time k i n o p r e n e had r e a c h e d s u f f i c i e n t l e v e l s w i t h i n t h e i n s e c t s , t h e c e l l s may have been a l r e a d y committed t o produce an a d u l t c u t i c l e . The second anomaly o c c u r r e d i n t h e precocene s t u d i e s . U n l i k e o t h e r s p e c i e s (Bowers e t a l . 1976; Pener e t a l . 1978), precocene t r e a t m e n t s a d m i n i s t e r e d t o a p t e r i f o r m nymphs o f M. p e r s i c a e d i d n o t i n d u c e p r e c o c i o u s metamorphosis. However, s u b s t a n t i a l impairment o f CA a c t i v i t y o c c u r r e d because l a r v i -p o s i t i o n r a t e s d e c l i n e d s i g n i f i c a n t l y i n i n s e c t s t r e a t e d w i t h precocene as f i r s t and second i n s t a r nymphs. I t i s n oteworthy t h a t l a r v i p o s i t i o n c o n t i n u e d a l b e i t a t a much re d u c e d r a t e . T h i s s u g g e s t s t h a t s u f f i c i e n t JH was p r e s e n t i n t h e s e i n s e c t s t o p e r m i t l i m i t e d r e p r o d u c t i v e a c t i v i t y b u t t o i m p a i r p r e c o c i o u s metamorphosis. S i m i l a r f i n d i n g s were r e p o r t e d i n the pea a p h i d (MacKauer e t a l . 1979). (c) S c l e r o t i z a t i o n I n a d d i t i o n t o r e g u l a t i n g m o l t i n g and metamorphosis, JH i s known t o i n f l u e n c e the a r c h i t e c t u r e o f t h e c u t i c l e . I n v a r i o u s s t u d i e s , JH has been shown t o f a v o u r t h e r e t e n t i o n o f the l a m e l l a t e - a p p e a r a n c e o f the l a r v a l e n d o c u t i c l e and i n f l u e n c e 74 t y r o s i n e m e t a b o l i s m ( N e v i l l e 1975). The l a t t e r e f f e c t i s i m p o r t a n t i n t h e c u r r e n t c o n t e x t i n t h a t t h e s c l e r o t i z i n g a g ent, N a c e t y l dopamine, and t h e major c u t i c u l a r pigment, m e l a n i n , a r e d e r i v a t i v e s o f t y r o s i n e . I n o t h e r s p e c i e s , t h e i r s y n t h e s i s i s r e g u l a t e d by ecdyson and b u r s i c o n ( N e v i l l e 1975) . I n p e r s i c a e , e x t e n s i v e s c l e r o t i z a t i o n and m e l a n i z a t i o n o c c u r s h o r t l y a f t e r e c d y s i s i n a l a t e a d u l t s . I f reduced s c l e r o t i z a t i o n and m e l a n i z a t i o n i n a p t e r o u s a d u l t s can be a t t r i b u t e d t o h i g h JH t i t e r s d u r i n g t h e nymphal s t a g e s , then the p r o c e s s e s s h o u l d be s u p p r e s s e d when a l a t i f o r m nymphs a r e t r e a t e d w i t h JHA. T h i s was c o n f i r m e d as k i n o p r e n e a p p l i c a t i o n s t o f i r s t , second, t h i r d , and f o u r t h i n s t a r a l a t i f o r m nymphs i n h i b i t e d s c l e r o t i z a t i o n and m e l a n i z a t i o n . A l t h o u g h s i m i l a r f i n d i n g s have been r e p o r t e d i n o t h e r a p h i d s p e c i e s ( M i t t l e r e t a l . 1976; Lees 1977, 1980), i t has n o t been e s t a b l i s h e d whether t h e i n h i b i t o r y e f f e c t s o f JH a r e d i r e c t ( v i z . a r i s i n g from e f f e c t s on t h e c u t i c l e o r t y r o s i n e metabolism) o r i n d i r e c t ( v i z . i n h i b i t i o n o f b u r s i c o n o r e c d y s o n ) . (d) C e p h a l i c s e n s o r y s t r u c t u r e s I n many a p h i d s p e c i e s , i n c l u d i n g M^ p e r s i c a e , o c e l l i and s e n s o r y a n t e n n a l s e n s o r i a (secondary r h i n a r i a , p l a c o i d s e n s i l l a ) a r e p r e s e n t i n a l a t e a d u l t s b u t a b s e n t i n a p t e r a e (Palmer 1952). U n l i k e p r e v i o u s a l a t e f e a t u r e s , t h e e f f e c t o f JH on the development and d i f f e r e n t i a t i o n o f t h e s e s e n s o r y o 75 s t r u c t u r e s i s c o n f l i c t i n g . I n p e r s i c a e , t h e o c e l l i and p a r t i c u l a r l y the a n t e n n a l p l a c o i d organs were much l e s s e a s i l y s u p p r e s s e d by t o p i c a l JHA a p p l i c a t i o n s t h a n o t h e r a l a t e c h a r a c t e r i s t i c s (Lees 1977, 1980). I n t h e l a t t e r s t u d y , hydropene- o r k i n o p r e n e - t r e a t e d i n s e c t s w h i c h e x h i b i t e d a maximal m o r p h o l o g i c a l response l a c k e d o c e l l i and had s m a l l abnormal p l a c o i d o r g a n s . A f t e r e x a m i n i n g the e f f e c t s o f the JHA on a l l p o s t n a t a l s t a g e s , Lees found no e v i d e n c e o f a J H - s e n s i t i v e s t a g e and c o n c l u d e d t h a t b o t h s t r u c t u r e s were r e l a t i v e l y i n s e n s i t i v e t o JH. I n A^ fabae and M^ p e r s i c a e , the development o f the secondary a n t e n n a l s e n s i l l a and o c e l l i were not a f f e c t e d when f o u r t h i n s t a r p r e s u m p t i v e gynoparae were r e a r e d on p l a n t s s p r a y e d w i t h k i n o p r e n e ( M i t t l e r e t a l . 1976). However, when t h e a l a t i f o r m o f f s p r i n g o f t h e s e females were a l s o m a i n t a i n e d on k i n o p r e n e - t r e a t e d f o l i a g e , they d e v e l o p e d i n t o a d u l t s w h i c h l a c k e d o c e l l i and had fewer o r no secondary s e n s o r i a . T h e r e f o r e , c o n t r a r y t o the c o n c l u s i o n o f L e e s , the f i n d i n g s o f M i t t l e r e t a l . s u g g e s t t h a t the s t r u c t u r e s a r e s e n s i t i v e t o JH a t some p a r t i c u l a r s t a g e ( s ) . T h i s was c o n f i r m e d i n the p r e s e n t s t u d y as t h e t i m i n g o f k i n o p r e n e a p p l i c a t i o n t o t h e v a r i o u s p o s t n a t a l s t a g e s had a s i g n i f i c a n t e f f e c t on o c e l l a r development. As r e p o r t e d by M i t t l e r e t a l . (197 6), f o u r t h i n s t a r a l a t i f o r m l a r v a e , w h i c h were t r e a t e d w i t h k i n o p r e n e , d e v e l o p e d i n t o a d u l t s w i t h a l m o s t 76 normal o c e l l i . When t r e a t e d t h i r d i n s t a r s d e v e l o p e d i n t o a d u l t s , t h e i r o c e l l i were s m a l l e r and malformed. In c o n t r a s t , when k i n o p r e n e was a p p l i e d t o f i r s t and second i n s t a r a l a t i -f o rms, o c e l l a r development was a l m o s t c o m p l e t e l y s u p p r e s s e d . T h i s s u g g e s t s t h a t e l e v a t e d JH l e v e l s d u r i n g t h e s e s t a g e s (such as i n a p t e r i f o r m s ) would i n h i b i t t h e development o f the o c e l l i . As d e s c r i b e d i n v i c i a e (Lees 1980), t h e se n s o r y a n t e n n a l s e n s o r i a were t h e l e a s t J H - l a b i l e a l a t e c h a r a c t e r i s t i c examined i n t h i s s t u d y . When k i n o p r e n e was a p p l i e d t o a l l f o u r p o s t n a t a l s t a g e s , the development o f t h e s e n s o r i a was abnormal b u t n o t t o t a l l y i n h i b i t e d . As abnor-m a l i t i e s became p r o g r e s s i v e l y more pronounced when younger i n s t a r s were t r e a t e d , t h e p r e s e n t f i n d i n g s s u ggest t h a t p e r -haps e l e v a t e d p r e n a t a l JH l e v e l s a r e i m p o r t a n t i n s u p p r e s s i o n o f t he s t r u c t u r e s . T h i s would perhaps e x p l a i n why M i t t l e r e t a l . (197 6) were a b l e t o p r e v e n t t h e development o f t h e s e n s o r i a when b o t h mothers and o f f s p r i n g were r e a r e d on k i n o p r e n e - t r e a t e d f o l i a g e , (e) Wing development I n D o r a l i s fabae (Von Dehn 1963), b r a s s i c a e (White 1968a; White and Lamb 1968) and t h e a n d r o c y c l i c s t r a i n o f p e r s i c a e ( M i t t l e r e t a l . 1976), a p t e r o u s v i r g i n o p a r a e w h i c h would n o r m a l l y g i v e b i r t h t o a l a t e o f f s p r i n g were i n d u c e d t o produce a p t e r o u s o f f s p r i n g when t r e a t e d w i t h JHA. 77 The c u r r e n t study s u b s t a n t i a t e s these f i n d i n g s and suggests t h a t high JH t i t e r s i n the maternal haemolymph and e a r l y nymphal stages i n h i b i t wing development and favour the p r o d u c t i o n of apterous morphs. When f o u r t h i n s t a r a l a t i f o r m nymphs were t r e a t e d w i t h 65 ppm kinoprene, they developed i n t o a l a t e s w i t h n o r m a l - s i z e d wings. S i m i l a r treatments a p p l i e d to t h i r d i n s t a r produced a d u l t s w i t h balloon-shaped wings. The e f f e c t s o f kinoprene were even more pronounced when the compound was a d m i n i s t e r e d to f i r s t and second i n s t a r a l a t i f o r m s . Although wing development was not t o t a l l y sup-pressed, the wingbuds i n emergent a d u l t s were rudimentary. Thus, e l e v a t e d JH t i t e r s d u r i n g p o s t n a t a l development, p a r t i -c u l a r l y i n neonate l a r v a e , c o u l d p o t e n t i a l l y i n h i b i t wing formation and favour the p r o d u c t i o n o f apterous morphs. To determine the p r e n a t a l e f f e c t s of JH on wing development, kinoprene was a d m i n i s t e r e d to newly-ecdysed apterous a d u l t s which had been r e a r e d under crowded c o n d i t i o n s . The o f f s p r i n g produced d u r i n g the f i r s t t h r e e days were a l s o crowded u n t i l a d u l t emergence. Although c o n d i t i o n s r e s u l t e d i n the p r o d u c t i o n of 10% apterae i n the c o n t r o l groups, over 75% of the o f f s p r i n g produced by the JHA-treated a d u l t s developed i n t o normal apterae. Even though c o n d i t i o n s favoured a l a t e p r o d u c t i o n , e l e v a t e d maternal JH l e v e l s r e -s u l t e d i n the p r o d u c t i o n o f apterous i n s e c t s . In M_^  p e r s i c a e , 78 crowding of a d u l t s and f i r s t i n s t a r nymphs favours a l a t e p r o d u c t i o n (Bonnemaison 1951). As kinoprene i n h i b i t e d a l a t e p r o d u c t i o n d u r i n g these stages, my f i n d i n g s suggest t h a t crowding suppresses JH s y n t h e s i s . Based on the h i s t o l o g i c a l appearance of the CA, White (1968b) and E l l i o t t (1975) a r r i v e d a t s i m i l a r c o n c l u s i o n s . These f i n d i n g s c o n t r a d i c t those of Applebaum e t a l . (1975) who a l s o examined the. e f f e c t s of JHA on wing develop-ment i n p e r s i c a e . Using a r t i f i c i a l d i e t s , these authors demonstrated t h a t c h l o r i n a t e d f a r n e s o i c a c i d (CFA) and an i s o m e r i c JH mixture had no apparent a p t e r i z i n g e f f e c t when adm i n i s t e r e d to a d u l t s and nymphs of p e r s i c a e . Since the authors observed on l y impaired development and h i g h m o r t a l i t y , they concluded t h a t any abnormal e f f e c t s induced by the JHA were merely p a t h o l o g i c a l . However, the b i o a s s a y method employed i n t h i s study i s open to c r i t i c i s m . F i r s t , CFA has r e c e n t l y been shown to be l e s s m o r p h o l o g i c a l l y - a c t i v e than kinoprene and q u i t e t o x i c to a d u l t aphids (Lees 19 80). Second, the dosages employed i n t h i s study appear q u i t e h i g h (5-2 5 u l JHA/ml. methanol). T h i r d , i n experiments on neonate l a r v a e , the s y n t h e t i c JH ( d i s s o l v e d i n methanol) was a p p l i e d to the P a r a f i l m s u r f a c e of the a r t i f i c i a l d i e t . As s y n t h e t i c JH i s very o i l - s o l u b l e , i t c o u l d d i s s o l v e i n the P a r a f i l m and not be absorbed by the i n s e c t s . F i n a l l y , a l l the e x p e r i -79 ments were performed on a r t i f i c i a l d i e t . A l t h o u g h th e s t u d i e s were d e s i g n e d so t h a t a s i g n i f i c a n t number o f a l a t e a d u l t s d e v e l o p e d , o n l y 7-15% o f the c o n t r o l s d e v e l o p e d i n t o a l a t e s . As some f a c t o r i n the d i e t appears t o be l i m i t i n g a l a t e f o r m a t i o n , the c o n c l u s i o n s o f Applebaum e t a l . a r e not s u r p r i s i n g . They p o s t u l a t e t h a t " i n t h e normal c o u r s e o f e v e n t s , a p h i d development i s d i r e c t e d towards th e p r o -d u c t i o n o f a p t e r o u s a d u l t s , a s i t u a t i o n where wing r u d i m e n t s a r e p r e s e n t and dormant due t o h i g h t i t r e o f endogenous JH. D i v e r s i o n t o winged a d u l t s would t h e n r e q u i r e s p e c i f i c ' i n i t i a t o r s ' , and a p p l i c a t i o n o f exogenous JH t o an a l r e a d y maximal l e v e l o f endogenous JH might s e r v e o n l y t o d i s r u p t t h e i n t e r n a l hormonal m i l i e u by an overabundance o f JH, r e s u l t i n g the a b n o r m a l i t i e s r e c o r d e d " . As i n p e r s i c a e , JHA have been shown t o i n h i b i t w ing development when a p p l i e d t o a l a t i f o r m nymphs and/or a l a t e - p r o d u c i n g a p t e r o u s a d u l t s o f v i c i a e (Lees 1977, 1980). D e s p i t e t h i s , Lees c o n c l u d e d t h a t JH i s n o t d i r e c t l y i n v o l v e d i n wing d e t e r m i n a t i o n i n t h i s s p e c i e s . However, the b i o a s s a y methods employed by Lees may have i n f l u e n c e d t h e r e s u l t s and t h e i r i n t e r p r e t a t i o n . S i n c e crowded mothers o f v i c i a e u s u a l l y produce b o t h a l a t e s and a p t e r a e w h i c h a r e i n d i s t i n -g u i s h a b l e u n t i l the t h i r d i n s t a r , Lees found i t n e c e s s a r y t o t r e a t t h e neonate l a r v a e and d i s c a r d t h o s e t h a t were subse-q u e n t l y r e v e a l e d as a p t e r a e . T h e r e f o r e , any o f t h e J H A - t r e a t e d 80 i n s e c t s w h i c h e x h i b i t e d a p t e r o u s c h a r a c t e r i s t i c s would have been e l i m i n a t e d from t h e r e p o r t e d r e s u l t s . In a d d i t i o n , when Lees examined t h e e f f e c t s o f JH on a d u l t a p t e r a e , o n l y t h o s e females w h i c h produced e x c l u s i v e l y a p t e r a e were r e p o r t e d i n t h e r e s u l t s . On t h i s b a s i s , Lees c o n c l u d e d t h a t m a t e r n a l JH l e v e l s a r e u n i m p o r t a n t i n w i n g f o r m a t i o n . T h i s may have i n t r o d u c e d e x p e r i m e n t a l b i a s because e x c l u s i v e a l a t e and a p t e r o u s f o r m a t i o n r a r e l y o c c u r s even under normal c o n d i t i o n s . C. LETHAL EFFECTS JHA have been shown t o have c o n s i d e r a b l e p o t e n t i a l i n t h e c o n t r o l o f a p h i d s (Tamaki 1973; Hrdy 1974; S t a a l 1975). The p r e s e n t i n v e s t i g a t i o n s have demonstrated t h a t t h e v a r i o u s s t a g e s and morphs o f p e r s i c a e d i f f e r i n t h e i r s e n s i t i v i t y t o k i n o p r e n e . The compound was q u i t e t o x i c t o most a l a t i f o r m nymphs p a r t i c u l a r l y t h e younger i n s t a r s . A l t h o u g h l e t h a l e f f e c t s were i m m e d i a t e l y a p p a r e n t , t h e m a j o r i t y o f t h e m o r t a l i t y o c c u r r e d d u r i n g t h e supernumerary and a d u l t s t a g e s . A p t e r i f o r m nymphs were even more s e n s i t i v e t o k i n o p r e n e . When t h e y were d i p p e d i n a 65 ppm k i n o p r e n e s o l u t i o n , v i r t u a l l y 100% m o r t a l i t y o c c u r r e d w i t h i n 24 h r s . T h i s s e n s i t i v i t y appears t o be due t o t h e p r e s e n c e o f h i g h endogenous JH l e v e l s i n a p t e r o u s morphs. S i n c e k i n o p r e n e mimics t h e e f f e c t s o f n a t u r a l JH, a f u r t h e r i n c r e a s e i n JH l e v e l s i n i n s e c t s which a l r e a d y have h i g h JH t i t e r s , would r e s u l t i n more immediate m o r t a l i t y . 81 REFERENCES AGkerman, L. 1926. The p h y s i o l o g i c a l - b a s i s of: wing produc-t i o n i n the g r a i n aphid. J . Exp. Z o o l . 44:1-61. Applebaum, S.W., B. Raccah and R. L e i s e r o w i t z . 1975. E f f e c t s of j u v e n i l e hormone and beta-ecdysone on wing determina-•-• t i o n i n the aphid, Myzus p e r s i c a e . -• J . Insec t P h y s i o l . 21: 1279-1281. • ' ' Blackman, R. 1974. The aphid l i f e - f o r m . In Aphids. Ginn & Comp. L t d . , London pp. 1-19. Bonnemaison, L. 1951. Determinisme de 1 ' a p p a r i t i o n des formes sexuees chez l e s aph i d i n a e . B u l l . Soc. H i s t . Nat. Toulouse 86:108-112. Bowers, W.S., T. Ohta, J.S. C l e e r , and P.A. M a r s e l l a 1976. Discovery o f i n s e c t a n t i - j u v e n i l e hormones i n p l a n t s . Science (Wash.) 193:542-547. Boyd, D.J. 1979. The i n s e c t i c i d a l p o t e n t i a l o f s e v e r a l i n s e c t growth r e g u l a t o r s f o r c o n t r o l of the green peach aphid, Myzus p e r s i c a e S., and the cabbage aphid, B r e v i c o r y n e  b r a s s i c a e L. B.Sc. (Agr.) T h e s i s , U n i v e r s i t y o f B r i t i s h Columbia. Bromley, A.K., J.A. Dunn, and M. Anderson 1979. U l t r a s t r u c t u r e of the antennal s e n s i l l a o f aphids. 1. C o e l o c o n i c and p l a c o i d s e n s i l l a . C e l l T i s s u e Res. 203:427-442. Chapman, R.F. 1975. The In s e c t s - S t r u c t u r e and F u n c t i o n . The E n g l i s h U n i v e r s i t i e s Press L t d . pp. 692-716. C l o u t i e r , C , and J:.M'; Perron 1975. Polymorphism and s e n s i -t i v i t y o f a j u v e n i l e hormone analogue i n the potato aphid, Macrosiphum euphorbiae (Homoptera: A p h i d i d a e ) . Ent. Exp. A'Ppl. 18_: 457-464. Davidson, J . 1927. On the occurrence of i n t e r m e d i a t e s i n Aphis ruminis L. and the r e l a t i o n s h i p t o a l a t e and apterous v i v i p a r o u s females. J . L i n n . Soc. Lond. 36:467-477. Dixon, A.F.G. and D.M. Glen 1971. Morph d e t e r m i n a t i o n i n the b i r d c h e r r y - o a t aphid Rhopalosiphum p a d i L. Ann. Appl. B i o l . 68:11-21. 82 E l l i o t t , H.J. 1975. Corpus a l l a t u m and o v a r i a n growth i n a p o l y m o r p h i c p a e d o g e n e t i c i n s e c t . N a t u r e (Lond.) 257:390-391. Engelmann.,: F. 1970. .-The P h y s i o l o g y o f I n s e c t R e p r o d u c t i o n . ; Pergamon P r e s s , O x f o r d . -E s s i g , . E.O. 1-926/.-: Insects;-and m i t e s o f . w e s t e r n N o r t h /America. M a c m i i l a n Company-,. New York. G i l b e r t , L . I . ( e d . ) 1975. The J u v e n i l e Hormones. Plenum P r e s s , New York and London. Goodman, L . J . 1975. The n e u r a l o r g a n i z a t i o n and p h y s i o l o g y o f t h e i n s e c t d o r s a l o c e l l u s . I n The Compound Eye and V i s i o n o f I n s e c t s . G.A. H a r r i d g e , ed. C l a r e n d o n P r e s s , O x f o r d , pp. 595. H a l e s , D.F. 1976. J u v e n i l e hormone and a p h i d polymorphism. In Phase and C a s t e D e t e r m i n a t i o n i n I n s e c t s . M. L u s c h e r , ed. Pergmon P r e s s , New York. pp. 105-115. Han g a r t n e r , W., B. P e y e r , and W. M e i e r 1971. E f f e c t s o f a j u v e n i l e hormone analogue on t h e a p t e r o u s form o f t h e bean a p h i d , A p h i s fabae Scop. Meded. Fac. Land. R i j k s u n i v . Gent. 36:866-873. H i l l e R i s Lambers, D. 1966. Polymorphism i n aphididae.*Ann. Rev. E n t . 11;47-78. Krdy, I . 1974. E f f e c t s o f j u v e n o i d s on i n s e c t i c i d e s u s -c e p t i b l e and r e s i s t a n t a p h i d s (Myzus p e r s i c a e , A p h i s  fabae, and T h e r i o a p h a s i s m a c u l a t a . , Homoptera, A p h i d i d a e ) . A c t a E n t . Bohem. 71;361-381. Johnson, B., and P.R. B i r k 1960. S t u d i e s on wing polymorphism i n a p h i d s - I . The development p r o c e s s i n v o l v e d i n t h e p r o d u c t i o n o f t h e d i f f e r e n t forms. Entomol. Exp. A p p l . 3:327-339. K i t z m i l l e r , J.B. 1950. The time i n t e r v a l between d e t e r m i n a t i o n and d i f f e r e n t i a t i o n o f w i n g s , o c e l l i , and wing muscles i n t h e a p h i d Macrosiphum S a n d b o r n i ( G i l l e t t e ) . Am. Nat. 8£:23-50. K l o d n i t s k y . I . 1912. B e i t r a e g e Zur K e n n t n i s des G e n e r a t i o n s -w e c h s e l b e i e i n i g e n A p h i d i d a e . Z o o l . J a h r . A b t . S y s t . Geog. u. B i o l . , Bd. 33:445-520. 83 L e c k s t e i n , P.M. 1976. The r o l e o f t h e corpus a l l a t u m i n p r e n a t a l wing d e t e r m i n a t i o n i n Megoura v i c i a e . J . I n s e c t P h y s i o l . 22:1-117-1.121. L e e s , A.D. 1961. C l o n a l polymorphism i n a p h i d s . . Symp. R. Entomol. Soc. Lond. !L: 69-7 9. Le e s , A.D. 1966. The c o n t r o l o f polymorphism i n a p h i d s . Adv. I n s e c t P h y s i o l . 3_:207-210. L e e s , A.D. 1967. The p r o d u c t i o n o f t h e a p t e r o u s and a l a t e forms i n t h e a p h i d Megoura v i c i a e B u c k t o n , w i t h s p e c i a l r e f e r e n c e t o t h e r o l e o f c r o w d i n g . J . I n s e c t P h y s i o l . 12:289-318. L e e s , A.D. 1977. A c t i o n o f j u v e n i l e hormone mimics on t h e r e g u l a t i o n o f l a r v a l - a d u l t and a l a r y polymorphism i n a p h i d s . N ature (Lond.) 267:46-48. Lees, A.D. 1980. The development of j u v e n i l e hormone s e n s i -t i v i t y i n a l a t e of the aphid Megoura v i c i a e . J . I n s e c t Physiol.'26:143-156. Mackay, P.A. 1977. A l a t a - p r o d u c t i o n by an aphid: the " i n t e r n a l t i m e r " concept and maternal age e f f e c t s . J . I n s e c t P h y s i o l . 23:889-893. Mackay, P.A. and W.G. W e l l i n g t o n . 1975. A comparison o f the r e p r o d u c t i v e p a t t e r n s of apterous and a l a t e v i r g i n o p a r a e Acyrtho siphon pisum (Homoptera: A p h i d i d a e ) . Can. Ent. 107:1161-1166. MacKauer, M. , K..K. N a i r and G.G. Unnithan.- 197 9. E f f e c t s o f p r e c o c e n e - I I on a l a t e p r o d u c t i o n i n t h e pea a p h i d , A c y r t h o s i p h o n pisum (Homoptera: A p h i d i d a e ) . Can. J . Z o o l . 57:856-859. Masner,.P., W.S. Bowers, M. K a l i n and T. Muhle. 1979. E f f e c t , o f p r e c o c e n e - I I on t h e e n d o c r i n e r e g u l a t i o n o f d e v e l o p -ment and r e p r o d u c t i o n i n t h e bug, O n c o p e l t u s f a s c i a t u s . Gen. Comp. E n d o c r i n . 6^:99-108. M i t t l e r , T.E.,.S.G. Nassar and G.B. S t a a l . 1976. Wing d e v e l o p -ment and p a r t h e n o g e n e s i s i n d u c e d i n p r o g e n i e s o f k i n o p r e n e -t r e a t e d gynoparae o f A p h i s fabae and Myzus p e r s i c a e . J . I n s e c t P h y s i o l . 22:1717-1725. N e i l s , J.D. 1912. Wing p r o d u c t i o n i n a p h i d s (Hemip.) E n t . News. X X I I I : 1 4 9 - 1 5 1 . 84 Nemec, V., T.T. Chen, and G.R. Wyatt 1978. P r e c o c i o u s a d u l t l o c u s t , L o c u s t a m i g r a t o r i a m i g r a t o r i o i d e s i n d u c e d by precocene. A c t a E n t . Bohem. 75:285-286. N e v i l l e , A.C. 1975. B i o l o g y o f the A r t h r o p o d C u t i c l e . S p r i n g e r -V e r l a g New York. "/:. . Noda, I . 1961. The emergence o f winged v i v i p a r o u s female i n a p h i d - X I . E f f e c t s o f some f a c t o r s upon wing development i n Macrosiphum g r a n a r i u m . Mem. Ephime U n i v . 11:320-327. Palmer, M.A. 1952. A p h i d s o f The Rocky Mountain Region. The A.B. H i r s c h f e l d P r e s s Denver, C o l o r a d o . pp.325 P a q u i n , R.C.R. and J.M. P e r r o n 1978. A c t i o n a n t i j u v e n i l i s a n t e Du precocene 1 s u r S c h i s t o e e r c a g r e g a r i a (Forsk;) N a t u r a l i s t e Can. 105:425-427. P e d e r s e n , L.E.K. 1978. E f f e c t s o f a n t i - j u v e n i l e hormone (preco c e n e - I ) on t h e development o f L o c u s t a m i g r a t o r i a . L. Gen. Comp. Endocr. 36:502-509. Pener, M.P., L. Orshan, and J . DeWilde 1978. P r e c o c e n e - I I causes a t r o p h y o f c o r p o r a a l l a t a i n L o c u s t a m i g r a t o r i a . N a ture (Lond.) 272:350-353. P r a t t , G.E., and W.S. Bowers 1977. Precocene I I i n h i b i t s j u v e n i l e hormone b i o s y n t h e s i s by c o c k r o a c h c o r p o r a a l l a t a i n v i t r o . N a ture (Lond.) 265:548-550. R i v n a y , E. 19 37. M o i s t u r e as t h e f a c t o r a f f e c t i n g wing de-velopment i n t h e c i t r u s a p h i d , I o x a p t e r a a u r a n t i i Boy. B u l l . E n t . Res. 28:173-179. Scho o n v e l d , H. 1979. P r e c o c e n e - i n d u c e d c o l l a p s e and r e a b -s o r p t i o n o f c o r p o r a a l l a t a i n nymphs o f L o c u s t a m i g r a t o r i a . E x p e r i e n t i a . 35:363-364. S h i n j i , G.O. 1918. A c o n t r i b u t i o n t o t h e p h y s i o l o g y o f wing development i n a p h i d s . B i o l . B u l l . 35:95-116. S h u l l , A.F. 1928. D u r a t i o n o f l i g h t and t h e wings o f t h e a p h i d Macrosiphum s o l a n i f o l i i . A r c h . E n t w i c k l u n g s m e c h . Organ. • 115:825-851. S h u l l , A.F. 1938. Time o f d e t e r m i n a t i o n and time o f d i f -f e r e n t i a t i o n o f a p h i d wings. Amer. Nat. 72:170-179. 85 S t a a l , G.B. 1975. I n s e c t growth r e g u l a t o r s w i t h j u v e n i l e hormone a c t i v i t y . Ann. Rev. Ent. 20:416-460 Sutherland, O.R.W. 1969. The r o l e o f crowding i n the p r o -d u c t i o n o f a l a t e forms by two s t r a i n s o f the pea aphid, A c y r t h o s i p h o n pisum. J . I n s e c t P h y s i o l . 1 5 : 1 3 8 5 - 1 4 1 0 . Sutherland, O.R.W. 1970. An i n t r i n s i c f a c t o r i n f l u e n c i n g a l a t e p r o d u c t i o n by two s t r a i n s o f the pea aphid, A c y r t h o s i p h o n pisum. J . In s e c t P h y s i o l . 16:1349-1350. Tamaki, G. 1973. I n s e c t developmental i n h i b i t o r s : e f f e c t o f r e d u c t i o n and delay caused by j u v e n i l e hormone mimics on the p r o d u c t i o n o f winged migrants o f Myzus p e r s i c a e (Homoptera: Aphididae) on peach t r e e s . Can. Ent. 105: 761-765. Toba, H.H., J.D. Paschke and S. Friedman 1967. Crowding as the primary f a c t o r i n the p r o d u c t i o n o f the gamic a l a t e form o f T h e r i o a p h i s muculata (Homoptera: A p h i d i d a e ) . J . I n s e c t P h y s i o l . 13:381-391. Turner, W.F., and A.C. Baker 1916. On occurrence o f an i n t e r -mediate i n Aphis pomi. Ent. Soc. Wash. Proc. 17:4 2-52. Unnithan, G.C. and K.K. N a i r 1979. The i n f l u e n c e o f corpus a l l a t u m a c t i v i t y on the bug Oncopeltus f a s c i a t u s to precocene 1, 2, 3. Ann. Ent. Soc. Am. 72:38-40. Unnithan, G.C, K.K. N a i r , and W.S. Bowers 1977. Precocene-induced degeneration o f the corpus a l l a t u m o f a d u l t females o f the bug Oncopeltus f a s c i a t u s . J . I n s e c t P h y s i o l . 23:1081-1094. Unnithan, G.C, K.K. N a i r , and A. Syed 1980. Precocene-induced metamorphosis i n the d e s e r t l o c u s t S c h i s t o e e r c a g r e g a r i a . E x p e r i e n t i a . 36:135-136. Von Dehn, M. 1963. Hemmung der G l u e g e l b i l d u n g durch F a r n e s o l b e i der Schwarzen Bohnenlaus, D o r a l i s fabae Scop. Naturwiss. 50 : 578-579. Wadley, F.M. 1923. F a c t o r s a f f e c t i n g the p r o p o r t i o n o f a l a t e and apterous forms o f aphids. Ann. Ent. Soc. Am. 16:279-303. W e l l i n g t o n , W.G. 1974. Bumblebee o c e l l i and n a v i g a t i o n a t dusk. Science (Wash.) 183:550-551. 86 White, W.S. 1946. The environmental c o n d i t i o n s a f f e c t i n g the g e n e t i c mechanism o f wing p r o d u c t i o n i n the chrysanthemum aphid. Am. Nat. 80:245-270. White, D. 19 65. Changes i n s i z e of the corpus a l l a t u m i n a polymorphic i n s e c t . Nature (Lond.) 208:807. White, D. 1968a. P o s t n a t a l treatment o f the cabbage aphid with a s y n t h e t i c j u v e n i l e hormone. J . I n s e c t P h y s i o l . 14:901-912. White, D. 19 6 8b. Cabbage aphid: E f f e c t o f i s o l a t i o n on form and endocrine a c t i v i t y . Science (Wash.) 159:218-219. White, D., and K.P. Lamb 1968. E f f e c t s o f a s y n t h e t i c j u v e n i l e hormone on a d u l t cabbage aphids and t h e i r progeny. J . I n s e c t P h y s i o l . 14:395-402. White, D. 1971. Corpus a l l a t u m a c t i v i t y a s s o c i a t e d w i t h development o f wingbuds i n cabbage aphid embryos and l a r v a e . J . I n s e c t P h y s i o l . 17:761-773. Wigglesworth, V.B. 1970. I n s e c t hormones. O l i v e r and Boyd, Edinburgh. 87 Appendix l a ( r e f e r s t o T a b l e 5) E f f e c t s o f k i n o p r e n e on t h e f e c u n d i t y o f f i r s t i n s t a r a p t e r i f o r m nymphs o f a p t e r o u s a d u l t s C o n t r o l DAYS # INSECT 1 2 3 4 5 6 7 8 9 10 Total Mean 1 0 3 3 4 5 4 4 3 3 2 31 3.1 2 0 4 3 3 3 4 3 4 3 3 30 3.0 3 0 3 4 4 5 5 3 4 4 2 35 3.5 4 2 3 4 3 4 4 3 3 3 4 33 3.3 5 0 3 3 4 4 3 5 3 4 2 31 3.1 6 0 2 4 3 5 3 4 4 3 3 31 3.1 Total Mean S.E. 3 0.5 0.3 18 3.0 0.2 21 3.5 0.2 21 3.5 0.2 26 4.3 0.3 23 3.8 0.3 22 3.C 0.3 21 3.5 0.2 20 3.3 0.2 16 2.6 0.3 191 31.8 0.78 19.1' 3.18 0.18 DAYS # INSECT Kinoprene-1 2 - t r e a t e d 3 4 5 6 7 8 9 10 Total Mean 1 0 3 3 4 3 6 5 3 4 2 33 3.3 2 0 3 4 3 5 4 3 4 3 3 32 3.2 3 0 2 4 3 3 5 5 3 4 2 31 3.1 4 2 3 3 4 5 5 4' 3 3 3 36 3.6 5 1 3 4 2 6 3 4 3 2 4 32 3.2 6 1 2 4 3 5 3 4 4 2 2 31 3.1 Total 4 17 22 19 27 26 25 20 18 16 195 19.5 Mean 0.66 2.66 3.66 3.16 4.50 4.33 4.16 3.33 3.00 2.66 32.5 3.25 S.E. 0.33 0.21 0.21 0.30 0.50 0.49 0.33 0.32 0.39 0.16 0.76 0.07 Appendix l b ( r e f e r s t o T a b l e 5) E f f e c t s o f k i n o p r e n e on t h e f e c u n d i t y o f second i n s t a r a p t e r i f o r m nymphs o f a p t e r o u s a d u l t s DAYS # INSECT C o n t r o l 1 2 3 4 5 6 7 8 9 10 Total . Mean 1 0 3 4 4 5 5 4 3 3 2 33 3.3 2 0 4 3 4 4 6 3 4 4 2 34 3.4 3 0 3 4 3 4 * 14 2.8 4 0 3 3 4 4 4 5 3 3 3 32 3.2 5 2 2 4 3 3 5 4 4 4 3 34 3.4 6 0 3 4 5 5 4 4 3 2 3 33 3.3 Total Mean 0 S.E. 0 2 18 .33 3.00 .33 0.21 22 3.66 0.21 23 3.80 0.30 25 4.16 0.30 24 4.80 0.37 20 4.00 0.31 17 3.40 0.24 16 3.20 0.37 13 2.60 0.24 180 30 3.21 19.38 3.23 0.09 DAYS # INSECT Kinoprene-1 2 - t r e a t e d 3 4 5 6 7 8 9 10 Total Mean 1 0 2 3 4 5 5 3 4 4 3 33 3.3 2 0 2 2 4 3 6 4 3 3 2 29 2.9 3 2 3 4 4 5 4 3 4 2 4 35 3.5 4 1 4 3 5 4 6 4 3 3 3 36 3.6 5 0 2 4 5 4 3 4 3 2 4 31 3.1 6 0 4 3 3 6 3 4 3 3 3 33 3.3 Total Mean 0 S.E. 0 3 17 .50 2.83 .34 0.40 19 3.16 0.30 25 4.16 0.30 27 4.50 0.42 27 4.50 3.56 22 3.66 0.21 20 3.33 0.21 17 > 2.83 0.30 19 3.16 0.30 197 32.83 1.04 19.7 3.28 0.10 Note: * denotes d e a t h 89 Appendix ± c ( r e f e r s t o T a b l e 5) E f f e c t s o f k i n o p r e n e on t h e f e c u n d i t y o f t h i r d i n s t a r a p t e r i f o r m nymphs o f a p t e r o u s a d u l t s C o n t r o l DAYS # INSECT 1 2 3 4 5 6 7 8 9 10 Total Mean 1 0 3 4 4 5 6 4 3 4 3 36 3.6 2 0 4 3 4 6 5 4 4 3 3 36 3.6 3 0 2 4 3 4 5 3 3 3 2 29 2.9 4 0 3 3 5 4 6 4 3 3 3 34 3.4 5 2 3 * 5 2.5 6 2 4 3 4 3 6 4 3 2 4 35 3.5 Total Mean 0 S.E. 0 4 .66 .42 19 3.16 0.30 17 3.40 0.24 20 4.00 0.31 22 4.40 0.50 28 5.60 0.24 19 3.80 0.20 16 3.20 0.20 15 3.00 0.31 15 3.00 0.31 175 29.16 4.94 19.50 3.25 0.18 Kinoprene-- t r e a t e d DAYS # INSECT 1 2 3 4 5 6 7 8 9 10 Total Mean 1 0 3 4 5 4 4 3 4 2 4 33 3.3 2 0 3 3 3 6 3 4 2 3 3 30 3.0 3 1 2 4 4 5 3 4 3 3 3 31 3.1 4 0 3 3 5 4 5 3 4 4 2 33 3.3 5 2 2 4 3 5 4 3 3 2 3 31 3.1 6 0 3 3 4 4 5 2 4 2 2 29 2.9 Total 3 Mean 0.50 S.E. 0.37 16 2.66 0.21 21 3.50 0.22 24 4.00 0.36 28 4.66 0.33 24 4.00 0.36 19 3.16 0.30 20 3.33 0.33 16 2.66 0.33 17 2.83 0.30 187 31.16 0.65 18.69 3.11 0.07 Note: * denotes d e a t h 90 Appendix I d ( r e f e r s t o T a b l e 5) E f f e c t s o f k i n o p r e n e on t h e f e c u n d i t y o f f o u r t h i n s t a r a p t e r i f o r m nymphs o f a p t e r o u s a d u l t s C o n t r o l DAYS # INSECT 1 2 3 4 5 6 7 8 9 10 Total Mean 1 0 3 2 4 3 5 4 3 2 2 28 2.8 2 0 2 4 3 5 3 6 4 3 2 32 3.2 3 0 3 2 4 4 6 3 4 2 4 32 3.2 4 0 2 4 3 5 4 5 3 4 3 33 3.3 5 2 2 3 4 4 3 6 4 2 4 34 3.4 6 2 3 4 4 5 4 3 2 5 3 34 3.4 Total Mean S.E. 4 0.66 0.42 15 2.50 0.22 19 3.16 0.40 22 3.66 0.21 26 4.33 0.33 25 4.16 0.47 27 4.50 0.56 20 3.33 0.33 18 3.00 0.51 18 3.00 0.51 193 32.16 0.90 19.3 3.21 0.09 DAYS # INSECT Kinoprene-1 2 - t r e a t e d 3 4 5 6 7 8 9 10 Total Mean 1 0 3 4 3 5 4 3 4 2 3 31 3.1 2 0 4 3 4 3 6 4 3 2 4 33 3.3 3 0 3 4 3 3 5 4 3 2 3 30 3.0 4 0 2 4 3 3 6 3 2 4 3 30 3.0 5 2 2 4 4 5 3 4 4 3 2 33 3.3 6 1 4 3 3 6 4 3 2 4 4 33 3.3 Total Mean S.E. 3 0.50 0.34 18 3.00 0.37 22 3.60 0.21 20 3.30 0.21 25 4.16 0.54 28 4.60 0.19 . 21 3.50 0.24 18 3.00 0.36 17 2.80 0.46 19 3.10 0.30 190 31.6 0.61 19 3.16 0.06 91 Appendix 2 ( r e f e r s t o F i g . 15) E f f e c t s o f k i n o p r e n e on t h e fe c u n d i t y o f n e w l y - e c y s e d a p t e r o u s a d u l t s C o n t r o l DAYS # INSECT 1 2 3 4 5 6 7 8 9 10 Total Mean 1 2 3 3 4 5 5 3 4 3 2 34 3.4 2 0 4 3 4 4 5 3 4 2 3 32 3.2 3 2 3 4 2 6 4 3 3 4 • 2 33 3.3 4 0 4 3 4 3 6 4 3 3 3 33 3.3 5 0 3 4 4 5 5 4 4 3 2 35 3.5 Total Mean S.E. 4 0.80 0.48 17 3.40 0.24 17 3.40 0.24 18 3.60 0.40 23 4.60 0.50 25 5.00 0.31 17 3.40 0.24 17 3.60 0.24 15 3.00 0.31 12 3.40 0.24 167 33.4 0.50 16.7 3.34 0.05 DAYS # INSECT Kinoprene-1 2 - t r e a t e d 3 4 5 6 7 8 9 10 Total Mean 1 0 2 4 4 5 5 3 4 4 2 33 3.3 2 0 3 4 5 4 6 2 4 3 3 34 3.4 3 0 2 3 4 4 6 3 4 2 4 32 3.2 4 2 3 4 2 5 3 4 2 2 4 31 3.1 5 1 4 4 4 2 6 3 4 3 3 34 3.4 Total Mean S.E. 3 0.60 0.40 14 2.80 0.37 19 3.80 0.20 19 3.80 0.48 20 4.00 0.54 26 5.20 0.58 15 3.00 0.31 18 3.60 0.40 14 2.80 0.37 16 3.20 0.37 164 32.8 0.58 16.4 3.28 0.05 92 Appendix 3a ( r e f e r s t o T a b l e 6) E f f e c t s o f k i n o p r e n e on t h e f e c u n d i t y o f f i r s t i n s t a r a p t e r i f o r m nymphs o f a l a t e a d u l t s C o n t r o l DAYS # INSECT 1 2 3 4 5 6 7 8 9 10 Total Mean 1 0 2 3 3 4 3 3 2 3 2 25 2.5 2 0 3 3 4 4 5 2 3 2 3 29 2.9 3 1 2 3 2 5 3 3 4 2 4 29 2.9 4 1 3 3 4 4 4 3 4 3 4 33 3.3 5 2 2 3 4 3 5 4 2 3 2 31 3.1 Total Mean S.E. 4 0.80 0.35 12 2.40 0.24 15 3.00 0.00 17 3.40 0.40 20 4.00 0.31 20 4.00 0.44 15 3.00 0.31 15 3.00 0.44 13 2.60 0.24 15 3.00 0.44 147 29.4 1.32 14.7 2.94 0.13 DAYS # INSECT Kinoprene-1 2 - t r e a t e d 3 4 5 6 7 8 9 10 Total Mean 1 0 2 3 4 3 3 4 2 3 2 26 2.6 2 0 3 3 4 4 2 4 3 3 2 28 2.8 3 1 2 3 4 3 3 4 2 3 3 28 2.8 4 0 4 3 5 3 4 3 4 4 2 32 3.2 5 1 2 4 3 5 3 4 3 3 2 30 3.0 Total Mean S.E. 2 0.40 0.24 13 2.60 0.46 16 3.20 0.20 20 4.00 0.31 18 3.60 0.40 15 3.00 0.31 19 3.80 0.20 14 2.80 0.37 16 3.20 0.20 11 3.20 0.20 144 28.8 1.01 14.4 2.88 0.10 93 Appendix 3b ( r e f e r s to Table 6) E f f e c t s o f kinoprene on the f e c u n d i t y o f second i n s t a r a p t e r i f o r m nymphs o f a l a t e a d u l t s C o n t r o l DAYS # INSECT 1 2 3 4 5 6 7 8 9 10 Total Mean 1 0 1 3 4 4 5 4 3 2 3 29 2.9 2 2 3 3 5 6 4 4 3 2 2 34 3.4 3 0 2 4 3 4 6 3 4 3 3 32 3.2 4 2 1 5 3 4 5 3 3 2 4 32 3.2 5 1 4 3 5 6 3 4 4 3 3 36 3.6 Total Mean S.E. 5 1.00 0.44 11 2.20 0.58 18 3.60 0.40 20 4.00 0.44 24 4.80 0.48 23 4.60 0.50 18 3.60 0.15 17 3.40 0.24 12 2.40 0.24 15 3.00 0.31 163 32.6 1.16 16.3 3.26 0.11 DAYS INSECT Kinoprene-1 2 - t r e a t e d 3 4 5 6 7 8 9 10 Total Mean 1 0 2 3 4 4 3 3 2 4 2 27 2.7 2 2 3 • 4 3 5 3 4 3 3 3 33 3.3 3 0 3 4 3 5 4 3 2 3 2 29 2.9 4 0 4 2 5 4 3 4 4 2 4 32 3.2 5 0 2 4 3 4 5 3 4 4 2 31 3.1 Total Mean S.E. 2 0.40 0.40 14 2.80 0.37 17 3.40 0.40 18 3.60 0.40 22 4.40 0.24 18 3.60 0.40 17 3.40 0.24 15 3.00 0.44 16 3.20 0.37 13 2.60 0.40 152 30.4 1.07 15.2 3.04 0.10 94 Appendix 3c ( r e f e r s t o Table 6) E f f e c t s o f kinoprene on the f e c u n d i t y o f t h i r d i n s t a r a p t e r i f o r m nymphs o f a l a t e a d u l t s C o n t r o l DAYS # INSECT 1 2 3 4 5 6 7 8 9 10 Total Mean 1 0 2 3 3 4 4 3 2 4 1 26 2.6 2 0 3 4 4 5 3 4 3 4 3 33 3.3 3 0 2 4 3 2 5 4 3 3 2 28 2.8 4 0 3 3 4 4 3 3 2 2 4 28 2.8 5 1 2 1 5 4 3 4 3 3 3 29 2.9 Total Mean S.E. 1 0.20 0.20 12 2.40 .0.24 15 3.00 0.54 19 3.80 0.37 19 3.80 0.48 18 3.60 0.40 13 3.60 ' 0.24 13 ' 2.60 0.24 16 3.20 0.37 13 2.60 0.50 144 28.8 1.15 14.4 2.88 0.11 DAYS # INSECT Kinoprene-1 2 - t r e a t e d 3 4 5 6 7 8 9 10 Total Mean ' 1 0 2 3 4 4 3 4 3 2 4 29 2.9 2 1 2 3 4 3 5 3 3 4 2 30 3.0 3 2 3 4 3 4 3 4 2 3 3 31 3.1 4 1 2 3 4 5 3 4 2 3 4 31 3.1 5 0 4 3 2 6 3 4 3 2 3 30 3.0 Total Mean S.E. 4 0.80 0.37 13 2.60 0.40 16 3.20 0.20 17 3.40 0.40 22 4.40 0.50 17 3.40 0.40 19 3.80 0.20 13 2.60 0.24 14 2.80 0.37 16 3.20 0.37 151 30.2 0.37 15.1 3.02 0.03 95 Appendix 3d ( r e f e r s t o T a b l e 6) E f f e c t s o f k i n o p r e n e on t h e f e c u n d i t y o f f o u r t h i n s t a r a p t e r i f o r m nymphs o f a l a t e a d u l t s C o n t r o l DAYS # INSECT 1 2 3 4 5 6 7 8 9 10 Total Mean 1 0 3 3 4 3 4 2 3 3 2 27 2.7 2 0 3 3 2 5 3 4 3 2 3 28 2.8 3 1 2 3 4 5 3 4 2 4 2 30 3.0 4 1 3 4 4 3 5 2 3 4 4 33 3.3 5 0 3 2 4 3 5 4 3 3 3 30 3.0 Total Mean S.E. 2 0.40 0.24 14 2.80 0.20 15 3.00 0.31 18 3.60 0.40 19 3.80 0.48 20 4.00 0.44 16 3.20 0.48 14 2.80 0.20 16 3.20 0.37 14 2.80 0.37 . 148 29.6 1.02 14.8 2.96 0.10 K i n o p r e n e - t r e a t e d DAYS # 1 2 3 4 5 6 7 8 9 10 Total Mean INSECT 1 0 2 3 4 5 4 3 4 2 4 31 3.1 2 0 3 4 4 5 3 4 2 4 3 32 3.2 3 1 2 3 3 4 3 4 3 3 2 28 2.8 4 2 3 3 5 2 4 3 4 2 4 32 3.2 5 0 3 2 5 4 3 2 4 4 3 30 3.0 Total 3 13 15 21 20 17 16 17 15 16 153 15.3 Mean 0.60 2.60 3.00 4.20 4.00 3.40 3.20 3.40 3.00 3.20 30.6 3.06 S.W. 0.40 0'.24 0.31 0.37 0.54 0.24 0.37 0.37 0.44 0.37 0.70 0.07 Appendix 4a, ( r e f e r s t o T a b l e 8) E f f e c t s o f p r e c o c e n e - I I on t h e f e c u n d i t y o f f i r s t i n s t a r a p t e r i f o r m nymphs o f a p t e r o u s a d u l t s C o n t r o l DAYS # INSECT 1 2 3 4 5 6 7 8 9 10 T o t a l Mean 1 0 3 3 4 5 4 4 3 3 2 31 3 . 1 2 0 4 3 3 3 4 3 4 3 3 30 3 . 0 3 1 3 4 4 5 5 3 4 4 2 35 3 . 5 4 2 3 4 3 4 4 3 3 3 4 33 3 . 3 5 0 3 3 4 4 3 5 3 4 2 31 3 . 1 6 0 2 4 3 5 3 4 4 3 3 31 3 . 1 T o t a l Mean S . E . 3 0 . 6 0 0 . 5 0 18 3 . 0 0 3 . 0 0 21 3 . 5 0 3 . 5 0 21 3 . 5 0 3 . 5 0 26 4 . 33 4 . 3 0 23 3 . 8 3 3 . 8 0 22 3 . 6 6 3 . 6 0 21 3 . 5 0 3 . 5 0 20 3 . 3 3 3 . 3 0 16 2 . 6 6 2 . 6 0 191 3 1 . 8 3 0 . 7 4 1 9 . 1 3 . 1 8 0 . 0 8 P r e c o c e n e - t r e a t e d DAYS # INSECT 1 . 2 3 4 5 6 7 8 9 10 T o t a l Mean 1 0 1 1 0 2 0 1 1 1 1 8 0 . 8 2 0 1 0 1 2 1 0 1 0 6 0 . 6 3 0 1 1 2 0 2 1 0 1 0 7 0 . 7 4 0 0 2 1 1 1 1 0 0 2 8 0 . 8 5 0 2 1 0 1 1 0 0 1 1 7 0 . 7 6 0 1 2 2 0 0 2 1 1 0 9 0 . 9 T o t a l Mean S . E . 0 0 0 6 1 . 0 0 0 . 2 5 7 1 . 1 6 0 . 3 0 6 1 . 0 0 0 . 3 6 6 1 . 0 0 0 . 3 6 5 0 . 8 3 0 . 3 0 5 0 . 8 3 0 . 3 0 3 0 . 5 0 0 . 2 2 4 0 . 8 0 0 . 2 0 4 0 . 8 0 0 . 3 7 45 7 . 5 0 0 . 4 2 4 . 5 0 . 7 5 0 . 04 K i n o p r e n e a p p l i c a t i o n t o f o u r - d a y - o l d p r e c o c e n e - t r e a t e d i n s e c t s DAYS # INSECT 1 2 3 4 5 6 7 8 9 10 T o t a l Mean 1 0 1 1 0 1 2 1 2 3 1 12 1 .2 2 0 2 0 2 0 0 2 2 2 3 13 1 . 3 3 0 0 2 1 1 1 3 1 3 2 14 1 .4 4 0 0 ' 1 1 2 3 . 1 3 2 1 14 1 .4 5 0 2 1 0 1 2 2 3 1 3 14 1 .4 6 0 0 2 1 * 3 0 . 7 T o t a l Mean S . E . 0 0 0 5 0 . 8 3 0 . 4 0 7 1 .16 0 . 3 0 5 0 . 8 3 0 . 3 1 5 1 . 0 0 0 . 5 0 8 1 . 6 0 0 . 5 0 9 1 .80 0 . 3 7 11 2 . 2 0 0 . 3 7 11 2 . 2 0 0 . 3 7 10 2 .20 0 . 4 4 70 1 1 . 6 0 1 .76 7 . 4 1 .24 0 . 1 0 N o t e : * d e n o t e s d e a t h Appendix 4b ( r e f e r s t o T a b l e 8) E f f e c t s o f p r e c o c e n e - I I on the f e c u n d i t y o f s e c o n d i n s t a r a p t e r i f o r m nymphs o f a p t e r o u s a d u l t s C o n t r o l DAYS # INSECT 1 2 3 4 5 6 7 8 9 10 T o t a l Mean 1 0 3 4 4 5 5 4 3 3 2 33 3 . 3 2 0 4 3 4 4 6 3 4 4 2 34 3 . 4 3 0 3 4 3 4 * 14 2 . 8 4 0 3 3 4 4 4 5 3 3 3 32 3 . 2 5 0 2 4 3 5 5 4 4 4 3 ' 34 3 . 4 6 2 3 4 5 5 4 4 3 2 3 35 3 . 5 T o t a l Mean S . E . 2 0 . 33 0 . 3 3 18 3 . 0 0 0 . 2 5 22 3 . 6 6 0 . 2 1 23 3 . 8 3 0 . 2 4 27 4 . 5 0 0 . 2 2 24 4 . 8 0 0 . 3 7 20 4 . 0 0 0 . 3 1 17 3 . 4 0 0 . 2 4 16 3 . 2 0 0 . 2 4 13 2 . 6 0 0 . 2 4 182 3 3 . 3 3 . 2 9 1 9 . 6 3 . 2 6 0 . 1 1 P r e c o c e n e - t r e a t e d DAYS # 1 2 3 4 5 6 7 8 9 10 T o t a l Mean INSECT 1 0 1 0 2 1 1 0 1 2 1 9 0 . 9 2 0 0 2 0 2 1 1 2 0 2 10 1 . 0 3 0 1 1 1 0 0 1 * 4 0 . 5 4 0 1 2 2 1 1 0 1 0 0 8 0 . 8 5 0 0 1 0 0 2 1 1 1 0 6 0 . 6 6 0 2 0 0 2 1 1 0 0 0 6 0 . 6 T o t a l 0 5 6 5 6 6 4 5 3 3 43 4 . 4 Mean 0 0 . 8 3 1 . 0 0 0 . 8 3 1 . 0 0 1 . 0 0 0 . 6 0 1 . 0 0 0 . 6 0 0 . 5 0 7 . 1 6 0 . 7 3 S . E . 0 0 . 33 0 . 3 6 0 . 4 0 0 . 3 6 0 . 2 5 0 . 2 1 0 . 31 0 . 4 0 0 . 4 0 0 . 9 0 0 . 0 8 K i n o p r e n e a p p l i c a t i o n t o f o u r - d a y - o l d p r e c o c e n e - t r e a t e d i n s e c t s DAYS # INSECT 1 2 3 4 5 6 7 8 9 10 T o t a l Mean 1 0 2 1 0 2 2 3 2 2 3 17 1 . 7 2 0 0 1 0 1 3 1 2 4 2 14 1 .4 3 0 0 1 2 0 2 2 2 2 2 14 1 .4 4 0 0 2 1 0 1 3 1 3 3 14 1 . 4 5 ' 0 0 0 1 0 2 2 2 2 2 11 1 . 1 6 0 2 1 2 1 1 1 3 3 2 16 1 .6 T o t a l Mean S . E . 0 0 0 4 0 . 6 6 0 . 4 2 6 1 .00 0 . 2 5 6 1 . 0 0 0 . 36 4 0 . 6 6 0 . 3 3 11 1 . 8 3 0 . 30 12 2 . 0 0 0 . 3 6 12 2 . 0 0 0 . 2 5 16 2 . 6 6 0 . 3 3 14 2 . 33 0 . 2 1 86 1 4 . 3 3 0 . 8 4 8 . 6 1 . 4 3 0 . 0 8 N o t e : * d e n o t e s d e a t h Appendix. 4 c ( r e f e r s t o T a b l e 8 ) E f f e c t s o f p r e c o c e n e - I I on t h e f e c u n d i t y o f t h i r d i n s t a r a p t e r i f o r m nymphs o f a p t e r o u s a d u l t s C o n t r o l DAYS # INSECT 1 2 3 4 5 6 7 8 9 10 T o t a l Mean 1 0 3 4 4 5 6 4 3 4 3 36 3 . 6 2 0 4 3 4 6 5 4 4 3 3 36 3 . 6 3 0 2 4 3 4 5 3 3 3 2 29 2 . 9 4 0 3 3 5 4 6 4 3 3 3 34 3 . 4 5 2 3 * 5 2 . 5 6 2 4 3 4 3 6 4 3 2 4 35 3 . 5 T o t a l Mean S . E . 4 0 . 6 0 0 . 4 2 19 3 . 1 6 0 . 3 0 17 3 . 4 0 0 . 31 20 4 . 0 0 0 . 5 0 22 4 . 4 0 0 . 2 4 28 5 . 6 0 0 . 2 0 19 3 . 8 0 0 . 2 0 16 3 . 2 0 0 . 2 0 15 3 . 0 0 0 . 31 15 3 . 0 0 0 . 3 1 175 2 9 . 1 6 4 . 9 4 1 9 . 5 3 . 2 5 0 . 1 8 DAYS INSECT P r e c o c e n e -1 2 • t r e a t e d 3 4 5 6 7 8 9 10 T o t a l Mean 1 0 2 3 2 1 0 0 3 2 2 15 1 . 5 2 0 0 1 2 2 3 0 2 3 2 15 1 . 5 3 0 0 1 1 3 2 3 1 1 0 12 1 . 2 4 0 * 0 5 0 4 3 2 2 2 3 2 2 3 23 2 . 3 6 0 3 4 3 3 2 3 2 3 0 23 2 . 3 T o t a l Mean S . E . 0 0 0 9 1 . 8 0 0 . 8 0 12 2 . 4 0 0 . 6 0 10 2 . 0 0 0 . 3 1 11 2 . 2 0 0 . 3 7 9 1 . 8 0 0 . 4 8 9 1 . 8 0 0 . 7 3 10 2 . 0 0 0 . 3 1 11 2 . 2 0 0 . 3 7 7 1 . 4 0 0 . 6 0 88 1 4 . 6 6 3 . 4 7 8 . 8 1 . 4 6 0 . 34 DAYS INSECT K i n o p r e n e 1 2 a p p l i c a t i o n 3 4 t o f o u r 5 - d a y - o l d p r e c o c e n e 6 7 8 ! - t r e a t e d i n s e c t 9 10 T o t a l Mean 1 0 2 1 2 1 3 2 4 4 3 22 2 . 2 2 0 0 3 1 2 4 3 3 3 2 21 2 . 1 3 0 3 1 3 4 3 3 4 3 3 27 2 . 7 4 0 1 2 2 4 4 3 3 2 3 24 2 . 4 5 2 2 1 * 5 1 . 6 6 1 0 2 3 3 4 4 3 3 2 25 2 . 5 T o t a l Mean S . E . 3 0 . 5 0 0 . 3 7 8 1 . 3 0 0 . 5 3 10 1 . 6 0 0 . 3 3 11 2 . 2 0 0 . 3 7 14 2 . 8 0 0 . 5 8 18 3 . 6 0 0 . 2 4 15 3 . 0 0 0 . 3 1 17 3 . 4 0 0 . 2 4 15 3 . 0 0 0 . 3 1 13 2 . 6 0 0 . 2 4 124 2 0 . 6 6 3^.25 1 3 . 5 2 . 2 5 0 . 9 1 N o t e : * d e n o t e s d e a t h 99 Appendix 4d ( r e f e r s t o T a b l e 8) E f f e c t s o f p r e c o c e n e - I I on t h e f e c u n d i t y o f f o u r t h i n s t a r a p t e r i f o r m nymphs o f a p t e r o u s a d u l t s C o n t r o l DAYS # INSECT 1 2 3 4 5 6 7 8 9 10 T o t a l Mean 1 0 3 2 4 3 5 4 3 2 2 28 2 . 8 2 0 2 4 3 5 3 6 4 3 2 32 3 . 2 3 0 3 2 4 4 6 3 4 2 4 32 3 . 2 4 0 2 4 3 5 4 5 3 4 3 33 3 . 3 5 2 2 3 4 4 3 6 4 2 4 34 3 - 4 6 2 3 4 4 5 4 3 2 5 3 35 3 . 5 T o t a l Mean S . E . 4 0 . 6 0 0 . 4 6 15 2 . 5 0 0 . 3 4 19 3 . 1 0 0 . 4 3 22 3 . 6 0 0 . 2 3 25 4 . 1 0 0 . 3 8 25 4 . 1 0 0 . 5 2 27 4 . 5 0 0 . 6 1 20 3 . 3 0 0 . 36 18 3 . 0 0 0 . 5 6 18 3 . 0 0 0 . 39 194 3 2 . 3 3 0 . 9 8 1 9 . 4 3 . 2 3 0 . 0 9 DAYS # INSECT P r e c o c e n e -1 2 t r e a t e d 3 4 5 6 7 8 9 10 T o t a l Mean 1 0 3 2 3 3 4 2 4 3 3 27 2 . 7 2 1 3 3 2 3 3 4 3 4 1 27 2 . 7 3 2 2 1 4 2 4 2 4 2 3 26 2 . 6 4 0 1 2 2 3 3 4 3 2 2 22 2 . 2 5 0 2 4 1 4 3 4 2 4 2 26 2 . 6 6 0 2 2 3 3 3 3 3 2 3 24 2 . 4 T o t a l Mean S . E . 3 0 . 5 0 0 . 4 3 13 2 . 1 6 0 . 3 3 14 2 . 3 0 0 . 4 6 15 2 . 5 0 0 . 4 6 18 3 . 0 0 0 . 2 8 20 3 . 3 0 0 . 2 1 19 3 . 1 0 0 . 4 3 17 2 . 8 0 0 . 3 8 16 2 . 6 0 0 . 4 5 14 2 . 3 0 0 . 3 6 152 2 5 . 3 3 0 . 8 0 1 5 . 2 2 . 5 3 0 . 0 8 DAYS INSECT K i n o p r e n e 1 2 a p p l i c a t i o n 3 4 t o f o u r - d a y -5 6 •old p r e c o c e n e - t r e a t e d i n s e c t s 7 8 9 10 T o t a l Mean 1 0 2 3 2 3 5 4 3 2 3 27 2 . 7 2 0 1 2 3 4 3 5 3 3 2 26 2 . 6 3- 0 3 1 4 2 5 2 4 2 4 27 2 . 7 4 0 1 3 2 4 3 4 4 2 3 26 2 . 6 5 0 4 2 3 2 4 5 3 4 2 29 2 . 9 6 0 3 2 1 4 3 5 4 3 3 28 2 . 8 T o t a l Mean S . E . 0 0 • 0 14 2 . 3 0 0 . 5 3 13 2 . 1 0 0 . 3 3 15 2 . 5 0 0 . 4 6 19 3 . 1 0 0 . 4 3 23 3 . 8 0 0 . 4 3 25 4 . 1 0 0 . 5 2 21 3 . 5 0 0 . 2 4 16 2 . 6 0 0 . 4 0 17 2 . 8 0 0 . 33 163 2 7 . 1 6 0 . 4 7 1 6 . 3 2 . 7 1 0 . 0 4 100 Appendix 4e ( r e f e r s t o T a b l e 8) E f f e c t s o f precocene-a p t e r o u s a d u l t s I I on the f e c u n d i t y o f newly--ecdysed DAYS # INSECT C o n t r o l 1 2 3 4 5 6 7 8 9 10 Total Mean 1 2 3 3 4 5 5 3 4 3 2 34 3.4 2 0 4 3 4 4 5 3 4 2 3 32 3.2 3 2 3 4 2 6 4 3 3 4 2 33 3.3 4 0 4 3 4 3 6 4 3 3 3 33 3.3 5 0 3 4 4 5 5 4 4 3 2 34 3.4 6 0 4 2 4 3 3 4 4 3 2 "39 2.9 Total Mean S.E. 4 0.66 0.42 21 3.50 0.22 19 3.16 0.30 22 3.60 0.33 26 4.33 0.49 28 4.66 0.42 21 3.50 0.22 22 3.70 0.21 18 3.00 0.25 14 2.30 0.21 195 32.50 0.76 19.5 3.25 0.07 DAYS Insect Precocene 1 2 - t r e a t e d 3 4 5 6 7 8 9 10 Total Mean 1 0 0 1 2 1 1 0 2 0 0 7 0.7 2 0 2 0 1 0 2 1 1 0 1 8 0.8 3 0 0 2 0 2 1 1 0 1 0 .7 0.7 4 0 0 3 0 2 1 2 1 1 1 11 1.1 5 0 0 2 2 0 0 2 0 1 2 9 0.9 6 0 1 1 1 2 0 1 1 0 0 7 0.7 Total Mean S.E. 0 0 0 3 0.60 0.36 9 1.50 0.42 6 1.00 0.36 7 1.16 0.40 5 0.83 0.30 7 1.16 0.30 5 0.83 0.30 3 0.53 0.22 4 0.66 0.33 49 8.16 0.65 4.9 0.81 0.06 101 Appendix 4e-- c o n t i n u e d K i n o p r e n e a p p l i c a t i o n t o p r e c o c e n e - t r e a t e d 24 h r s . o l d i n s e c t s DAYS # INSECT 1 2 3 4 5 6 7 8 9 10 Total Mean 1 0 0 2 0 2 0 3 4 2 3 16 1.6 2 0 0 2 1 2 1 4 2 3 2 17 1.7 3 0 1 1 3 0 3 2 3. 2 2 17 1.7 4 0 1 2 1 2 2 2 3 1 4 18 1.8 5 0 0 0 2 1 3 2 3 4 1 16 1.6 6 0 * 0 Total Mean S.E. 0 0 0 2 0.40 0.24 7 1.40 0.40 7 1.40 0.50 7 1.40 0.40 9 1.80 0.58 13 2.60 0.40 15 3.00 0.31 12 2.40 0.55 12 2.40 0.50 84 16.8 0.37 8.4 1.68 0.03 Ki n o p r e n e a p p l i c a t i o n t o p r e c o c e n e - t r e a t e d 4-day-old i n s e c t s DAYS # INSECT 1 2 3 4 5 6 7 8 9 10 Total Mean 1 0 2 1 3 4 3 4 2 3 1 23 2.3 2 1 0 2 3 3 5 3 4 2 3 26 2.6 3 0 1 0 3 3 4 3 4 3 3 25 2.5 4 1 0 2 2 4 3 4 3 4 1 24 2.4 5 0 2 1 3 3 4 3 4 2 4 26 2.6 6 0 * 0 Total Mean S.E. 2 0.33 0.21 5 1.00 0.44 6 1.20 0.37 14 2.80 0.20 17 3.40 0.24 19 3.80 0.37 17 3.40 0.24 17 3.40 0.40 14 2.80 0.37 12 2.40 0.60 124 24.8 0.58 12.4 2.48 0.05 Note: * denotes d e a t h 102 Appendix 5a. ( r e f e r s t o T a b l e 9) E f f e c t s o f p r e c o c e n e - I I on t h e f e c u n d i t y o f F i r s t i n s t a r a p t e r i f o r m nymphs o f a l a t e a d u l t s C o n t r o l DAYS # INSECT 1 2 3 4 5 6 7 8 9 10 T o t a l Mean 1 ' 0 2 3 3 4 4 3 3 2 1 25 2 . 5 2 2 1 4 3 3 4 2 3 3 2 27 2 . 7 3 0 2 4 3 4 3 4 3 4 1 28 2 . 8 4 0 3 2 4 4 3 2 3 3 2 26 2 . 6 5 2 2 1 3 4 2 3 4 2 4 27 2 . 7 6 0 0 1 * 1 0 . 3 T o t a l Mean S . E . 4 0 . 6 6 0 . 42 10 1 . 6 0 0 . 4 2 15 2 . 5 0 0 . 5 6 16 3 . 2 0 0 . 2 0 19 3 . 8 0 0 . 2 0 16 3 . 2 0 0 . 3 7 14 2 . 8 0 0 . 3 7 16 3 . 2 0 0 . 2 0 14 2 . 8 0 0 . 3 7 10 2 . 0 0 0 . 54 134 2 . 2 3 4 . 2 8 1 3 . 6 2 . 27 0 . 3 9 DAYS INSECT P r e c o c e n e -1 2 •treated 3 1 4 5 6 7 8 9 10 T o t a l Mean 1 0 1 2 2 0 0 1 0 2 0 8' 0 . 8 2 0 1 1 1 0 1 2 2 1 0 9 0 . 9 3 1 2 2 0 0 0 1 0 2 1 9 0 . 9 4 0 0 0 2 1 1 0 1 0 2 7 0 . 7 5 0 1 2 1 2 3 0 0 0 1 10 1 . 0 6 1 1 * 2 0 . 2 T o t a l Mean S . E . 2 0 . 3 3 0 . 2 1 6 1 . 0 0 0 . 2 5 7 1 . 4 0 0 . 4 0 6 1 . 2 0 0 . 37 3 0 . 6 0 0 . 4 0 5 1 . 0 0 0 . 5 4 4 0 . 8 0 0 . 3 7 3 0 . 6 0 0 . 4 0 5 1 . 0 0 0 . 4 4 4 0 . 8 0 0 . 37 45 7 . 5 0 1 . 1 7 4 . 5 0 . 7 5 0 . 0 4 K i n o p r e n e a p p l i c a t i o n t o f o u r - d a y - o l d p r e c o c e n e - t r e a t e d i n s e c t s DAYS # INSECT 1 2 3 4 5 6 7 8 9 10 T o t a l Mean 1 0 1 2 0 2 1 2 1 2 1 12 1 . 2 2 0 2 1 1 0 2 1 2 1 2 12 1 . 2 3 0 0 2 1 1 1 3 0 2 0 10 1 . 0 4 0 1 1 2 0 2 1 2 1 ' 1 11 1 . 1 5 0 1 0 1 2 1 1 2 0 2 10 1 . 0 6 0 * T o t a l Mean S . E . 0 0 0 5 1 . 0 0 0 . 3 1 6 1 . 2 0 0 . 3 7 5 1 . 0 0 0 . 3 1 5 1 . 0 0 0 . 4 4 7 1 . 4 0 0 . 2 4 8 1 . 6 0 0 . 4 0 7 1 . 4 0 0 . 4 0 6 1 . 2 0 0 . 3 7 6 1 . 2 0 0 . 3 7 55 1 1 . 0 0 0 . 4 4 5 . 5 1 . 1 0 0 . 0 4 N o t e : * d e n o t e s d e a t h 103 Appendix .5b ( r e f e r s t o T a b l e 9) E f f e c t s o f p r e c o c e n e - I I on t h e f e c u n d i t y o f s e c o n d i n s t a r a p t e r i f o r m nymphs o f a l a t e a d u l t s C o n t r o l DAYS # INSECT 1 2 3 4 5 6 7 8 9 10 T o t a l Mean 1 0 2 3 3 4 3 3 2 3 2 25 2 . 5 2 0 3 3 4 4 5 2 3 3 3 30 3 . 3 3 1 2 3 2 5 3 3 4 2 4 29 2 . 9 4 1 3 3 4 4 4 3 4 2 4 32 3 . 2 5 2 2 3 4 3 5 4 2 3 . 2 30 3 . 0 T o t a l Mean S . E . 4 0 . 80 0 . 3 7 12 2 . 4 0 0 . 2 4 15 3 . 0 0 0 . 0 0 17 3 . 8 4 0 . 4 0 20 4 . 0 0 0 . 3 1 20 4 .00 0 . 4 4 15 3 . 0 0 0 . 31 15 3 . 0 0 0 .44 13 2 . 6 0 0 . 2 4 15 3 . 0 0 0 . 4 4 146 2 9 . 2 0 1 . 1 5 1 4 . 9 2 . 9 8 0 . 1 3 DAYS INSECT P r e c o c e n e -1 2 •treated 3 4 5 6 7 ' 8 9 10 T o t a l Mean 1 0 2 1 0 0 2 2 0 1 0 8 0 . 8 2 0 1 0 1 2 1 0 1 0 1 7 0 . 7 3 0 1 2 1 1 0 1 2 0 1 9 0 . 9 4 0 0 • 1 0 2 1 2 0 1 1 8 0 . 8 5 1 2 1 2 1 1 1 . 1 0 0 10 1 . 0 T o t a l Mean S . E . 2 0 . 2 0 0 . 2 0 6 1 . 2 0 0 . 37 5 1 . 0 0 0 . 31 4 0 . 8 0 0 . 37 6 1 . 2 0 0 . 37 5 1 . 0 0 0 . 3 1 6 1 . 2 0 0 . 3 7 4 0 . 80 0 . 37 2 0 . 4 0 0 . 2 4 3 0 . 6 0 0 . 2 4 42 8 . 4 0 0 . 5 0 4 . 2 0 . 8 4 0 . 0 5 DAYS INSECT K i n o p r e n e 1 2 a p p l i c a t i o n 3 4 t o f o u r - d a y -5 6 •old p r e c o c e n e 7 8 i - t r e a t e d i n s e c t s 9 10 T o t a l Mean 1 0 1 2 0 3 1 2 3 0 3 15 1 . 5 2 0 1 1 2 0 3 0 2 1 2 12 1 .2 3 0 0 2 0 3 0 3 1 2 3 14 1 .4 4 1 1 0 1 1 2 3 1 2 0 12 1 . 2 5 0 1 1 2 0 2 2 2 3 1 14 1 .4 T o t a l Mean S . E . 1 0 . 2 0 0 . 2 0 4 0 . 8 0 0 . 2 0 6 1 . 2 0 0 . 3 7 5 1 . 0 0 0 . 4 4 7 1 . 4 0 0 . 6 7 8 1 . 6 0 0 . 5 0 10 2 . 0 0 0 . 5 4 9 1 . 8 0 0 . 37 8 1 . 6 0 0 . 5 0 8 1 . 6 0 0 . 5 0 67 13 .40 0 . 6 0 6 . 7 1..34 0 . 0 6 104 Appendix 5c ( r e f e r s t o T a b l e 9) E f f e c t s o f p r e c o c e n e - I I on t h e f e c u n d i t y o f t h i r d i n s t a r a p t e r i f o r m nymphs o f a l a t e a d u l t s C o n t r o l DAYS # INSECT 1 2 3 4 5 6 7 8 9 10 T o t a l Mean 1 0 2 3 3 4 4 • 3 2 4 1 25 2 . 5 2 0 3 4 4 5 3 4 2 4 3 32 3 . 2 3 0 2 4 3 2 5 4 3 3 2 28 2 . 8 4 0 3 3 4 4 3 3 2 2 4 28 2 . 8 5 1 2 1 5 4 3 4 3 3 3 29 2 . 9 T o t a l Mean S . E . 1 0 . 2 0 0 . 2 0 12 2 . 4 0 0 . 2 4 15 3 . 0 0 0 . 5 4 19 3 . 8 0 0 . 3 7 19 3 . 4 0 0 . 6 0 18 3 . 6 0 0 . 4 0 18 3 . 6 0 0 . 2 4 12 2 . 4 0 0 . 2 4 16 3 . 2 0 0 . 3 7 13 2 . 6 0 0 . 5 0 142 2 8 . 4 0 1 . 1 2 1 4 . 2 2 . 8 4 0 . 1 1 P r e c o c e n e - t r e a t e d DAYS INSECT 1 2 3 4 5 T o t a l Mean S . E . 0 0 2 1 0 3 0 . 60 0 . 4 4 0 3 3 1 3 10 1 1 4 2 2 10 1 . 0 0 1 . 8 0 2 . 0 0 2 . 0 0 0 . 4 4 0 . 3 7 0 . 6 3 0 . 8 9 2 2 3 2 1 10 2 . 0 0 1 . 4 0 0 . 3 1 0 . 2 4 0 3 2 1 3 9 1 . 8 0 0 . 5 8 1 . 4 0 0 . 5 0 10 1 2 1 0 1 5 1 . 0 0 T o t a l Mean 9 14 22 15 15 75 15 0 . 3 7 2 . 0 7 0 . 9 1 . 4 2 . 2 1 . 5 1 . 5 7 . 5 1 . 5 0 0 . 2 0 K i n o p r e n e a p p l i c a t i o n t o DAYS # 1 2 3 4 5 INSECT 1 0 2 1 1 2 2 0 0 3 3 3 3 0 2 2 3 4 4 2 1 2 2 5 5 1 0 3 2 3 T o t a l 3 5 11 11 17 Mean 0 . 6 0 1 . 0 0 2 . 2 0 2 . 2 0 3 . 4 0 S . E . 0 . 4 0 0 . 4 0 0 . 3 7 0 . 3 7 0 . 5 0 - d o y - o l d p r e c o c e n e t r e a t e d i n s e c t s 6 7 8 9 10 T o t a l Mean 3 4 4 ' 3 3 23 2 . 3 4 4 3 3 2 25 2 . 5 3 4 3 2 4 27 2 . 7 4 3 3 • 3 2 27 2 . 7 5 4 3 2 4 27 2 . 7 19 19 16 13 15 129 1 2 . 9 3 . 8 0 3 . 8 0 3 . 2 0 2 . 6 0 3 . 0 0 2 5 . 8 0 2 . 5 8 0 . 3 7 0 . 2 0 0 . 2 0 0 . 2 4 0 . 4 0 0 . 8 0 0 . 0 8 105 Appendix 5d ( r e f e r s t o T a b l e 9) E f f e c t s o f p r e c o c e n e - I I on the f e c u n d i t y o f f o u r t h i n s t a r a p t e r i f o r m nymphs o f a l a t e a d u l t s C o n t r o l DAYS # INSECT 1 2 3 4 5 6 7 8 9 10 T o t a l Mean 1 0 3 3 4 3 4 2 3 3 2 _27 2 . 7 2 0 3 3 2 5 3 4 3 2 3 28 2 . 8 3 1 2 3 4 5 3 4 2 4 2 30 3 . 0 4 1 3 4 4 3 5 2 3 4 4 33 3 . 3 5 0 3 2 4 3 5 4 3 3 3 30 3 . 0 T o t a l Mean S . E . 2 0 . 4 0 0 . 2 4 14 2 . 8 0 0 . 4 4 15 3 . 0 0 0 . 31 18 3 . 6 0 0 . 4 0 19 3 . 8 0 0 . 4 8 20 4 . 2 0 0 . 4 8 16 3 . 2 0 0 . 4 8 14 2 . 8 0 0 . 2 0 16 3 . 2 0 0 . 3 7 14 2 . 8 0 0 . 37 148 2 9 . 6 1 . 0 2 1 4 . 8 2 . 9 6 0 . 1 0 DAYS # INSECT P r e c o c e n e -1 2 • t r e a t e d 3 4 5 6 7 8 9 10 T o t a l Mean 1 0 0 2 3 2 2 3 3 2 2 19 1 . 9 2 0 2 0 1 3 4 2 4 2 4 22 2 . 2 3 0 1 0 1 4 5 2 3 3 1 20 2 . 0 4 0 1 0 3 2 4 5 2 4 1 22 2 . 2 5 1 0 2 0 3' 2 3 2 3 3 19 1 . 9 T o t a l Mean S . E . 1 0 . 5 0 0 . 2 0 4 0 . 8 0 0 . 3 7 4 0 . 8 0 0 . 4 8 8 1 . 6 0 0 . 60 14 2 . 8 0 0 . 3 7 17 3 . 4 0 0 . 6 0 15 3 . 0 0 0 . 5 4 14 2 . 8 0 0 . 3 7 14 2 . 8 0 0 . 3 7 11 2 . 2 0 0 . 5 8 102 " 2 0 . 4 0 0 . 6 7 1 0 . 2 2 . 0 4 0 . 0 7 K i n o p r e n e a p p l i c a t i o n t o f o u r •-day-•old p r e c o c e n e ! t r e a t e d i n s e c t s DAYS # INSECT 1 2 3 4 5 6 7 8 9 10 T o t a l Mean 1 0 0 1 2 4 2 2 3 1 1 16 1 .6 2 0 2 0 3 2 2 2 3 2 2 18 1 . 8 3 0 0 2 0 3 1 3 1 2 4 16 1 . 6 4 0 0 2 1 1 2 3 2 2 1 14 1 .4 5 0 0 0 3 0 3 1 2 2 1 12 1 . 2 T o t a l Mean S . E . 0 0 0 2 0 . 4 0 0 . 4 0 5 1 . 0 0 0 . 5 1 9 1 . 8 0 0 . 5 8 10 2 . 0 0 0 . 7 0 10 2 . 0 0 0 . 3 1 11 2 . 2 0 0 . 37 11 2 . 2 0 0 . 37 9 1 . 8 0 0 . 2 0 9 1 . 8 0 0 . 5 8 76 1 5 . 2 0 1 . 0 1 7 . 6 1 . 5 2 0 . 1 0 Appendix 6 106 Taxonomic a u t h o r i t i e s f o r s p e c i e s quoted i n t h e t h e s i s ; COMMON NAME LATIN NAME AUTHORITY Green peach a p h i d Myzus p e r s i c a e ( S u l z . ) Cabbage a p h i d B r e v i c o r y n e b r a s s i c a e (L.) Cowpea a p h i d A p h i s c r a c c i v o r a (Koch.) Chrysanthemum a p h i d M a c r o s i p h o n i e l l a s a n b o r n i ( G i l l . ) P o t a t o a p h i d Macrosiphum e u p h o r b i a e (Thos.) V e t c h a p h i d Megoura v i c i a e (Buckt.) Pea a p h i d A c y r t h o s i p h o n pisum ( H a r r i s ) B l a c k bean a p h i d A p h i s fabae (Scop.) C o c k r o a c h P e r i p l a n e t a americana (L.) M i l k weed bug On c o p e l t u s f a s c i a t u s ( D a l l . ) M i g r a t o r y l o c u s t L o c u s t a m i g r a t o r i a (L.) D e s e r t l o c u s t S c h i s t o e e r c a g r e g a r i a (Forsk.) 

Cite

Citation Scheme:

        

Citations by CSL (citeproc-js)

Usage Statistics

Share

Embed

Customize your widget with the following options, then copy and paste the code below into the HTML of your page to embed this item in your website.
                        
                            <div id="ubcOpenCollectionsWidgetDisplay">
                            <script id="ubcOpenCollectionsWidget"
                            src="{[{embed.src}]}"
                            data-item="{[{embed.item}]}"
                            data-collection="{[{embed.collection}]}"
                            data-metadata="{[{embed.showMetadata}]}"
                            data-width="{[{embed.width}]}"
                            data-media="{[{embed.selectedMedia}]}"
                            async >
                            </script>
                            </div>
                        
                    
IIIF logo Our image viewer uses the IIIF 2.0 standard. To load this item in other compatible viewers, use this url:
https://iiif.library.ubc.ca/presentation/dsp.831.1-0095157/manifest

Comment

Related Items