Annals of Plant Protection Sciences

Two field trials were conducted to evaluate the field efficacy of fipronil 80WG at 100, 80, 50 and 40 g a.i. ha⁻¹ in trial I and 60, 50 and 40 g a.i. ha⁻¹ in trial II to assess their efficacy in reducing the thrips damage in grapes. The reduction in thrips damage to berries observed were 82.2, 81.7, 81.0 and 80.4% during Trial I and 84.3, 83.8 and 83.2% during Trial II, respectively. All the treatments were at par among each other and with the relative check regent^® 80WG at 40 and 50 g a.i. ha⁻¹. Fipronil treatments were found better than the standard checks viz., chlorpyriphos 20EC at 200 g a.i. ha⁻¹ and dimethoate 30EC at 375 g a.i. ha⁻¹ in grapes. The results revealed that the doses of fipronil 80WG recorded significantly minimum fruit damage and there was no symptoms of phytotoxicity in the treated plots. Fipronil 80 WG at 40g a.i. ha⁻¹ and 50g a.i. ha⁻¹ under laboratory condition effected 32.5 and 40% mortality of coccinellid, Cryptolaemus montrouzieri adults but found comparatively safer and superior in their safety over conventional insecticide, chlorpyriphos 20 EC at 200 g a.i. ha⁻¹ and dimethoate 30 EC at 375 g a.i. ha⁻¹ after 24 hours of treatment. The marketable bunch yield of grapes increased up to 19.1 and 16% over control in Trial I and II, respectively.