Laboratory and field studies on the effect of sequential application of pesticides on susceptibility and on some biological aspects of mite tetranychus cinnabarinus
Laboratory and field studies on the effect of sequential application of pesticides on susceptibility and on some biological aspects of mite tetranychus cinnabarinus
Watson, W.M.; E.B.heiry M.M.; Guirguis, M.W.
Acarologia 26(1): 17-24
1985
Laboratory and field evaluation on the effect of sequential application of dicofol, omethoate and cypermethrin insecticides on the susceptibility, biology and population density of the mite T. cinnabarinus were studied through the course of the present investigation. The susceptibility of adult female mites to dicofol, omethoate and cypermethrin applied sequentially over 3 generations was studied. Biological studies indicate that the life span of selected mites was extended, this was more pronounced in the scehemes of cypermethrin / cypermethrin / cypermethrin and cypermethrin /dicofol / omethoate. Egg production was significantly increased in case of cypermethrin / cypermethrin / cypermethrin but decreased in omethoate / omethoate /omethoate. The percent of hatchability was significantly decreased, this was highly occurred in cypermethrin / omethoate / dicofol. Field studies show that plots sprayed 3 times with dicofol recorded the highest reduction in mite population infesting soybean plants. This indicate the necessity of using a specific potent acaricide on soybean in case cypermethrin is used to control the cotton leafworm to avoid outbreak of mite infestation.