Toxicity and field trials of seed dressing with 70% thiamethoxam WS against Phyllotreta striolata

The experiment determinate of the efficacy of 70% thiamethoxam WS on Phyllotreta striolata (F.). The result showed that 70% thiamethoxam WS have obvious poison and antifeedant effect on adult beetles in the 3 days and 5 days after emergence. The result of the LC50 value of thiamethoxam were 6.73%and 13.8%. The AFC50 value of thiamethoxam were 1.09% and 3.26%.The result of field trial indicated that 70% thiamethoxam WS had high control efficacy against Phyllotreta striolata (Fabricius), but high concentrations may produce effects on Seed Germination. The control effects were 55.16% ~ 46.60%, 86.10% ~ 77.15% and 89.46% ~ 46.60% with the quality percentage of thiamethoxam were 2.5%, 5% and 7.5% after emergence from one to five days.