RESUMO
Newly developed Phytopesticidal formulations from pongam and neem oils were evaluated for their feeding deterrent activity using leaf disc choice and no-choice methods, and genotoxic study using comet assay against Helicoverpa armigera at different concentrations of 5, 10, 15, and 20 ppm. Among various phytopesticidal formulations, neem and pongam oils at 1:1 ratio, called PONNEEM showed significant feeding deterrent activity against H. armigera at 20 ppm concentration and wasgenotoxic to H. armigera (P>0.001). The comet parameters, namely tail moment (arbitrary units), tail length (µm) and tail DNA (%) were observed at all the concentrations of PONNEEM. Statistically significant changes in all the comet parameters of H. armigera were observed at 20 ppm (P<0.001). Feeding deterrent and genotoxicity effect of PONNEEM could be applied as phytopesticide for controlling the lepidopteran insect pests.
RESUMO
Antifeedant and growth regulating activities of PONNEEM, an oil formulation containing neem and pungam (karanj) oils were evaluated along with individual neem and karanj oils and Nimbicidine, a commercial neem-based pesticide against fourth instar larvae of Spodoptera litura (Fab.). Among all the treatments, PONNEEM recorded the maximum antifeedant activity (88.6%) at 0.6%. Neem and karanj individual treatments as well as PONNEEM extended larval duration compared to control. Pupal weight and fecundity were significantly reduced and pupal period was greatly increased by PONNEEM treatment compared to other treatments. The PONNEEM was found to be compatible with Trichogramma chilonis Ishii, an egg parasitoid of many lepidopteran pests, at 0.15, 0.3 and 0.5% concentrations. PONNEEM did not affect the parasitoid emergence significantly at 0.3% concentration compared to control. PONNEEM also showed growth disruption activity against fourth instar larvae.