الفهرس 
Insecticidal activityOnly 14 pages are availabe for public view
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Abstract
Four d i f f e r e n t s p e c i e s o f f o o d p l a n t s , g a r l i c ( A l l i u m s a t i v u m ) ; P a r s l e y ( P e t r o s e l i n u m c r i s p u m ) ; o n i o n ( A l l i u m c e p a ) , and c o r i a n d e r ( C o r i a n d r u m s a t i v u m ) , p e r t a i n i n g t o d i f f e r e n t f a m i l i e s were s c r e e n e d f o r t h e i r t o x i c i t y a n d / o r t h e i r s y n e r g i s t i c a c t i v i t y a g a i n s t m o s q u i t o l a r v a e , Culex pipiens pipiens L. . They were s e l e c t e d on t h e b a s i s o f t h e i r p r o b a b l e t o x i c i t y t o i n s e c t s a n d / o r t h e i r p h a r m a c o l o g i c a l , t o x i c o l o g i c a l o r p h y s i c o l o g i c a l e f f e c t s which t h e y , o r t h e i r r e l a t e d s p e c i e s may h a v e on o t h e r a n i m a l s . I n a s s e s s i n g t h e i r t o x i c i t y t h e p l a n t s o r p l a n t p a r t s were e x t r a c t e d a t t h e r a t e of 30 g/100 ml a c e t o n e . A c e t o n e e x t r a c t s were s c r e e n e d f o r t h e i r t o x i c i t y a g a i n s t m o s q u i t o l a r v a e . R e s u l t s a n a l y s e d a c c o r d i n g t o t h e method of L i t c h f i e l d and Wilcoxon ( 1 9 4 9 ) . LCs0 v a l u e s were 7 . 0 , 2 0 . 0 , 40.0 a n d 7 0 . 0 ppm f o r t h e a c e t o n e e x t r a c t s of 4. s a t i v u m , P. c r i s p u m , I& c e p a and C. s a t i v u m xeqectively. T h e s e r e s u l t s r e v e a l e d t h a t g a r l i c and p a r s l e y e x t r a c t s showed p r o m i s i n g i n s e c t i c i d a l e f f e c t a g a i n s t m o s q u i t o l a r v a e . 3 . The v o l a t i l e o i l s of t h e most p r o m i s i n g p l a n t s . , g a r l i c and p a r s l e y , ,;ere i s o l a t e d by steam d i s t i l l a - t i o n and t h e i r p e r c e n t a g e s w e r e 0 . 5 6 8 and 0.06 % , r e s p e c t i v e l y . 4. Volatile oils of garlic and parsley were screened for their toxicity and/or synergistic activity to the public health insect, C. pipiens pipiens L. larvae. LC50 values of the tested volatile oils were as follows; garlic oil = 2.5 ppm and parsley oil = 20.0 ppm. LC50 of garlic oil was consistently lower than the corresponding whole plant extract . These results indicate that the active principle responsible for the toxicity of garlic may be present in its volatile oil. Three synthetic pyrethroids, esbiol, neopynamin, and sumithrin were screened for their toxicity against the mosquito larvae. Esbiol proved to be the most toxic with LC50 value of 0.39 ppm followed by neopynamin and sumithrin with LC50 values of 1.2 and 1.3 ppm, respectively. Results of synergism studies revealed that parsley oil synergized two insecticides, esbiol and sumithrin, while garlic oil synergized esbiol only. These preliminary investigations regarding the toxicity and synergistic activity of the active principle of garlic, garlic oil, to Culex larvae revealed a potential source of a potent mosquito larvicide for mosquito control and a potent synergist for pyrethroid against the same insect.