Anureet Kaur Chandi
Abstract
Plutella xylostella (Linnaeus) adults tend to autotomize their metathoracic legs at the trochanter-femur joint after walking on surface coated with insecticides. Only 2.5 per cent adults from susceptible population of P. xylostella experienced leg autotomy as compared to 10 per cent resistant adults. Among the various testinsecticides, fenvalerate exerted maximum influence with the composite mean value of leg autotomy at 13.35 per cent while spinosad affected only 1.65 per cent adults. Thus, the leg autotomy allowed P. xylostella to avoid the full effects of insecticides poisoning by eliminating part of dosage before it moves from the legs to the rest of the body. Influence of fenvalerate and spinosad, however, was maximum as regards knocked down effect of all the test-insecticides.