Compatibility of spinosad with Trichogramma chilonis (Ishii) (Hymenoptera: Trichogrammatidae) in integrated pest management of Sitotroga cereallela

With a view to use Trichogramma chilonis as a parasitoid in the integrated pest management, the effect of different concentrations of Spinosad (0.2, 0.15. 0.1 0.05 and 0.01%) was studied on the parasitoid under laboratory conditions. The results showed that 0.2% gave the minimum parasitism in egg, larva and pupa and during oviposition preference test. At 0.01% concentration, the spinosad showed less toxicity to the parasitoid in oviposition preference test followed by the larval stage. In egg stage, low percent parasitism showed toxicity of chemical to the parasitoid. Emergence time data followed almost same pattern as observed in case of percent parasitism. The 0.2, 0.15 and 0.10% concentrations increased the emergence time of parasitoid in pupal stage and oviposition preference test. Significantly lower emergence time was observed in 0.05 and 0.01% in larval stage. Significantly lower adult longevity was observed in all stages at all concentrations. The effect of Spinosad on adult T. chilonis was found extremely toxic as it gave 100% mortality within 15 minutes of exposure. Spinosad was applied at different concentration viz., 0.005% and 0.001%. Individual wasp were observed during approximately three minutes, first in absence and then in presence of spinosad. Movement activity was estimated with the help of computer based software Abid's Trackmove on an arena divided in to grids. The wasp exposed to 0.005% took more of the effect than the wasp exposed to 0.001%. It was observed that the total movement of wasp under spinosad effect was decreased while ineffective time period (of the wasp) increased. Although average speed during the whole observation period shows increase, average speed excluding the points of no movement decreased.