The purpose o! this work was lo Investigate the effects of Iwo pLmt
extracts in acetone (datura leaves and black pepper seeds). the botanical
insecticide. neenىazal—T. and the organophosphonis insecticide chiorpyrifos—
methyl alone and the mixtures of chlorpvrifos—methyl with the other three
compounds at ils half recommended rate on sonic insects infesting cabbage
plants, nanىelv cabbage aphid (Brei’icorvne b,’assicacL.), cabbage hniterfl
(Pieris hrassicae’L.) and diamondback moth (PlitIc//a ?naLu/ij’ennls Curtis)
Results of the field experiments, conducted during t 9)5/96 and 1996/97 seasons
at the agricultural experimental station o!’ (Ile Facnltv of Agriculture. Moshtohor.
Tukh. Qualyubia revealed the folحo ing :
I— Effect of the Plant Extracts and Insecticides on the Tested Insects :
LI- Cabbage aphid, B. brassicac :
Average number of the adults and immature stages of B. bra.s’.s’icue per
3 square inch/plant was obviously decreased after 3 days from spraying and
afterwards increased gradually until the next spraying aller two weeks post-
treatments, Reduction vaines of the individuals were after 3 days post—treatment
from 24-90 % for the various treatments. These values were decreased
significantly at the 14th day of treatment and ranged from 0.9—32 %.
At the highest concentrations nsed. chlorpyrifos— methyl was the most
effective compound against B. bra,vsicac stages followed by iieemai,ai—T, black
pepper seeds extract, hilc datura leaves extract was the least effective one.
1.2- Cabbage butterfly, P. brassicaL’:
Average number of P. hrassicac’—lanae per it) plants was decreased
clearly after 3 days post- treatment arid were froiii 1.3 - 12.7 for the various
treatments, these values increased afterwards and were between 13-19 larvae/I()
plants at the 14th day of treatments. Reduction values of larvae were between 12—
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