Effect of Combination of Insecticides against Maize Stem Borer, Chilo partellus (Swinhoe)

A field experiment was carried out during the Kharif season of 2024 at the Central Research Farm (CRF), SHUATS, Uttar Pradesh, India, to evaluate the effectiveness of various insecticidal treatments against Chilo partellus infestation in maize. The study was designed using a Randomized Block Design (RBD) comprising eight treatments with three replications each: T1 (Neem Oil 1% + Imidacloprid 17.8% SL), T2 (Chlorantraniliprole 18.5% SC + Azadirachtin 1500 ppm), T3 (Carbofuran 3G + Imidacloprid 17.8% SL), T4 (Imidacloprid 17.8% SL), T5 (Carbofuran 3G), T6 (Karanj Oil 3% + Imidacloprid 17.8% SL), T7 (Spinetoram 11.7% SC + Azadirachtin 1500 ppm), and an untreated control. Observations on larval population after the first and second sprays indicated that all treatments significantly reduced Chilo partellus infestation compared to the control. Among them, T7 (Spinetoram 11.7% SC + Azadirachtin 1500 ppm) was the most effective, recording the lowest larval population (2.22 and 1.36), followed by T2 (Chlorantraniliprole 18.5% SC + Azadirachtin 1500 ppm), T6 (Karanj Oil 3%+ Imidacloprid 17.8% SL), and T1 (Neem Oil 1% + Imidacloprid 17.8% SL). The least effective treatment was T5 (Carbofuran 3G), with the highest larval counts (3.53 and 2.46) after both sprays. These findings highlight the superior efficacy of Spinetoram 11.7% SC + Azadirachtin 1500 ppm in managing Chilo partellus under field conditions.