Evaluation of insecticidal efficacy against maize leaf aphid [Rhopalosiphum maidis (Fitch)] under inner terai condition of Nepal

Field experiments were carried out at the National Maize Research Program in Rampur, Chitwan, with objective of comparing effectiveness insecticides field for controlling maize leaf aphid (Rhopalosiphum maidis Fitch) during winter season 2019 and 2020. The design experiment was randomized complete block four replications. plot size 6 rows 5 m long spacing 60cm × 25cm. hybrid Rampur Hybrid-14 (RML-86/RML-96) used as experimental variety. efficacies five viz., thiomethoxam 25% w/w 0.2g/L (T1), acetamiprid 20%WP 2g/L (T2), flonicamid 50% WG 0.5g/L (T3), neemix 3ml/L(T4), imidacloprid 0.5ml/L(T5) untreated control (T6) treatments. recommended dose fertilizer 180: 60: 40 N: P2O5: K2O kg/ ha farm yard manure 10 t/ha seed rate 20kg/ha. Data on incidence, severity, yield components recorded. All tested significantly (P≤0.05) reduced plant infestation caused by aphid, thereafter increased grain compared to control. However, newer insecticide found most effective lower colony per (2.85), score (2.63), infested (7.33%) higher crop (7904.79kg/ha). application prior their severe infestations is necessary efficient aphid. research findings will assist farmers choosing applying best ensure management high yield.