Department of Entomology, Agricultural College, Bapatla-522 101, Guntur District, A. P.
Part of M. Sc. (Ag.) thesis submitted by the first author to Acharya N G Ranga Agricultural University, Rajendranagar, Hyderabad - 500 030.
Among the novel insecticides tested for the management of insecticide resistant Guntur strain of Spodoptera litura, novaluron was found to be the best at 72 h after treatment with higher relative toxicity than quinalphos (x77.0) and fenvalerate (x76.9) to which the pest has developed increased levels of resistance, followed by indoxacarb which was 63.6 and 63.1 times toxic than fenvalerate and quinalphos at LD50 level. At LD90 level indoxacarb was the best to eliminate the resistant individuals which was 50.0 and 37.7 times toxic than fenvalerate and quinalphos followed by novaluron which was 27.1 and 33.0 times toxic than quinalphos and fenvalerate. Profenophos was third in efficacy against resistant S. litura. Among the novel insecticides thiodicarb and spinosad showed poor efficacy against resistant Guntur strain of S. litura.
Relative toxicity, Spodoptera litura, Profenophos, Spinosad, Indoxacarb, Thiodicarb, Novaluron
