Efficacy of Virtako 1.5 G against Maize Stem Borer

A field experiment was conducted during Rabi 2011-12 and Kharif 2012 at Maize Research Centre, Rajendranagar, Hyderabad with DHM 117 maize hybrid inRandomized Block Design with eight treatments for bio-efficacy of Virtako 1.5 G @ 4, 5, 6, 7 kg/ha against maize stem borer along with three standard checks, Chlorantriniliprole 0.4 G @10 kg/ha, Thiamethoxam 75 SG @ 0.125 kg/ha, carbofuran 3 G @ 33 kg/ha at 15-18 days after sowing and an untreated control. Two years pooled data shows that among all the treatments, Virtako 1.5 G @ 7 kg/ha followed by chlorantriniliprole and virtako 6 kg/ha were highly effective in reducing the stem borer damage with 3.98, 4.41, 4.78 per cent infestation and 1.99, 1.94, 2.57 per cent dead hearts, respectively compared to 11.19 per cent infestation and 5.64 per cent dead hearts in control. Virtako 1.5 G@ 7 kg/ ha and 6 kg/ha were effective in reducing the aphid population to 5.33 aphids/plant compared to 12.33 aphids/plant in control. The population of Coccinella spp. and spiders differed slightly among the treatments.Virtako did not cause any of the phytotoxic symptoms on maize even at the dosage of 12 kg/ha. Highest grain yield of 10.11 t/ha and 5.09 t/ha was obtained in the plots treated with Virtako @ 7 kg/ha as compared to 9.15 and 4.28 t/ha in control during Rabi and Kharif, respectively.