Efficacy of different organic formulations against corn leaf aphid in wheat

Four organic formulations viz., Neemastra, Bramhastra, Agniastra, and Deshparni, were evaluated against leaf aphid, Rhopalosiphum maidis in three different concentrations (2.5, 5.0 and 7.5%) and their efficacy was compared with standard insecticide check i.e. thiamethoxam 25 WG @ 50 g a.i./ha. Two-year study indicated that thiamethoxam 25 WG @ 50 g/ha was found significantly superior overall other treatments and gave 76.93% aphid population reduction over control. Amongst the tested organic formulations, Bramhastra @ 7.5% was most effective against R. maidis with pooled aphid population of 8.96, 8.64 and 9.94 adults/earhead after 1, 2 and 7 days after spraying, respectively followed by Agniastra @ 7.5% with pooled aphid population of 9.25, 9.13 and 10.54 adults/earhead after 1, 2 and 7 days after spraying, respectively. Coccinellids were the major natural enemies observed during the study and their population was recorded highest in 2.5% dose of all four organic formulations. Highest grain yield of 58.30 q/ha was recorded in Bramhastra 7.5% treatment.