Efficacy of insecticides against helicoverpa armigera (Hubner) affecting soybean

A field experiment on bio-efficacy of chemical insecticides against H. armigera prevalent in soybean crop was carried out at Main Oilseeds Research Station, Junagadh Agricultural University, Junagadh during Kharif season of 2023. Of the seven insecticides evaluated against H.armigera, the treatment with chlorantraniliprole 10 + lambda-cyhalothrin 5 ZC @ 0.006% recorded the lowest (1.01) larvae/plant, which was at par with novaluron 5.25 + emamectin benzoate 0.9 SC @ 0.009% (1.11 larvae/plant) and novaluron 5.25 + indoxacarb 4.5 SC @ 0.016% (1.21 larvae/plant), three days after the first spray. More or less similar trend was observed 7 and 10 days after first spray as well as 3, 7 and 10 days after second spray. Highest (2640 kg/ha) yield of soybean was obtained in the treatment with chlorantraniliprole 10 + lambda-cyhalothrin 5 ZC 0.006% followed by novaluron 5.25 + emamectin benzoate 0.9 SC 0.009% (2346 kg/ha) and novaluron 5.25 + indoxacarb 4.5 SC 0.016% (2268 kg/ha). As per Incremental Cost Benefit Ratio (ICBR), treatment of chlorantraniliprole 10 + lambda-cyhalothrin 5 ZC 0.006% noted the highest (1:8.8) ICBR followed by thiamethoxam 12.6 + lambda-cyhalothrin 9.5 ZC 0.011% (1:8.3) and chlorpyriphos 50 + cypermethrin 5 EC 0.11% (1:7.1).