7种药剂拌种防治苗期玉米草地贪夜蛾效果评价

为筛选出对玉米安全，同时可降低草地贪夜蛾虫口基数、有效防控玉米苗期草地贪夜蛾发生的种子处理剂，试验特选用40%溴酰·噻虫嗪、50%氯虫苯甲酰胺、35%噻虫嗪、30%吡蚜·噻虫胺、20%呋虫胺、20%多杀霉素、10%高效氯氟氰菊酯7种不同类型杀虫剂对玉米种子进行处理。结果表明，在玉米出苗后7d, 50%氯虫苯甲酰胺拌种处理出苗率最高，为87.00%,各处理间出苗率差异不显著，与对照差异显著。防效方面，以40%溴酰·噻虫嗪、20%多杀霉素2个拌种处理最为突出，苗后7d虫口防效分别可达89.10%、87.14%,保苗率分别可达84.12%、81.80%;苗后14 d虫口防效分别可达74.10%、70.49%,保苗率分别可达72.59%、71.23%;苗后21 d虫口防效分别可达58.34%、56.37%,保苗率分别可达55.75%、53.09%。药效的持效期维持在苗后14～21 d左右。

Field Efficacy of Seven Maize Seed-coating Against Spodoptera frugiperda

The aim of this study is to identify the seed treatment agents to control Spodoptera frugiperda and improve maize seedling emergence.Seven seed-coating agents, including 40% cyantraniliprole and thiamethoxam, 50% chlorantraniliprole, 35% thiamethoxam, 30% pyrimidine clothianidam, 20% dinotefuran, 20% spinosad ,10% lambda-cyhalothrin were evaluated for their efficacy in field trials. The results showed that at 7d after maize yield, the highest emergence rate of 87.00% were achieved with 50% chlorantraniliprole,which did not significantly differ from the control. In terms of pest prevention, 40% cyantraniliprole and thiamethoxam and 20% spinosad were the most prominent, with the spodoptera frugiperda defense efficacy reaching 89.10%, 87.14% and seedling rates of 84.12% and 81.80%, respectively, at 7d after planting.At 14d after planting, Spodoptera frugiperda defense efficacy was 74.10% and 70.49%, respectively, and seedling rates were 72.59% and 71.23%, respectively. At 21 days after planting, Spodoptera frugiperda defense efficacy was 58.34% and 56.37%, respectively, and seedling rates were 55.75% and 53.09%, respectively. The effective period of these agents ranged from 14 to 21 days after planting.