Efficacy of entomopathogenic fungi for the management of onion thrips, Thrips tabaci Lind.

Different entomopathogens and insecticides were tested in field trials at Regional Research Station Salaru, Karnal (Haryana) for the management of Onion thrips (Thrips tabaci L.) in onion during Rabi season of 2006–07, 2007–08 and 2008–09. Significantly lowest thrips papulation (17.0 nymph/plant) were recorded with deltamethrin 2.8 EC (0.095%) and it was found to be at par with spinosad 45 SC (0.1%) at 7 days after last spray. The entomopathogenic fungus was less effective compared to chemical insecticide but among the entomopathogenic fungi Beauveria bassiana performed better in respect of reducing thrips population as well as increasing yield. Significantly highest gross yield (277 q/ha) was recorded with deltamethrin 2.8 EC. However, among entomopathogenic fungi highest gross yield (226 q/ha) was recorded with B. bassiana. The highest benefit cost ratio (46.75) was recorded with deltamethrin 2.8 EC followed by B. bassiana. at the rate of 0.4 percent (20.20).