LC50 of thiamethoxam and cyantraniliprole against mustard aphid, Lipaphis erysimi populations in Haryana ecosystem

A laboratory bioassay was conducted to determine the toxicity of thiamethoxam 25% WG and cyantraniliprole 10.26% OD against mustard aphid, Lipaphis erysimi (Kalt.), using the leaf dip method during rabi 2022-23 at CCS HAU, Hisar. Third instar nymphs reared on Brassica juncea (var. RH 725) were exposed to graded insecticide concentrations, and mortality was recorded at 24 and 48 hours. Thiamethoxam exhibited LC₅₀ values of 39.12 ppm and 28.69 ppm at 24 h and 48 h, respectively, while LC₉₀ values were 223.28 ppm and 193.33 ppm. Cyantraniliprole showed LC₅₀ values of 105.35 ppm and 93.33 ppm and LC₉₀ values of 660.90 ppm and 520.59 ppm at corresponding intervals. Steep dose-response slopes for thiamethoxam (2.70 and 2.24) and moderate slopes for cyantraniliprole (1.60 and 1.72) indicated consistent mortality trends across tested populations.