二十六种杀虫剂对不同龄期草地贪夜蛾幼虫的室内毒力

2019年初,草地贪夜蛾(Spodoptera frugiperda)入侵中国云南地区并迅速扩散。为筛选杀虫效果较好的药剂,室内测定了26种商品药剂对草地贪夜蛾初孵、3龄和5龄幼虫的毒力。结果表明,除6%鱼藤酮微乳剂、0.5%藜芦碱乳油外,其他药剂对初孵幼虫72 h后的校正死亡率均在70%以上。与初孵幼虫相比,大部分药剂对3龄幼虫的毒力有所下降,包括4.5%高效氯氟氰菊酯乳油、1.8%阿维菌素微乳剂、20%氯虫苯甲酰胺悬浮剂、0.5%苦参碱水剂等在内的11种药剂对3龄幼虫72 h后的校正死亡率均在70%以下。选取18种对3龄幼虫效果相对较好的药剂测定其对5龄幼虫的毒力,结果显示,除30%噻嗪·毒死蜱乳油、1.8%阿维菌素微乳剂、3.2%高氯·甲维盐微乳剂、56%阿维·炔螨特微乳剂、20%氯虫苯甲酰胺悬浮剂和10%氟苯虫酰胺悬浮剂外,其他12种药剂对5龄幼虫的校正死亡率均高于70%,包括6%甲维·虫螨腈乳油、44%氯氰·丙溴磷乳油、25%丙溴·灭多威乳油、15%茚虫威悬浮剂、30亿PIB·mL^-1甘蓝夜蛾核型多角体病毒悬浮剂、25%甲维·灭幼脲悬浮剂、2%甲氨基阿维菌素苯甲酸盐微乳剂、45%毒死蜱乳油、34%乙基·甲氧虫悬浮剂、5%虱螨脲乳油、40%氟虫·乙多素水分散粒剂、1%苦皮藤素乳油。

Laboratory toxicity of 26 insecticides against different instar larvae of Spodoptera frugiperda

In the early 2019, Spodoptera frugiperda invaded Yunnan Province of China and spread rapidly. In order to screen pesticides with high control efficacies to S. frugiperda, the toxicities of 26 commercial pesticides were determined on the newly hatching, third and fifth instar larvae of S. frugiperda in laboratory. The results showed that except for 6% rotenone EC and 0.5% veratrine EC, the corrected mortalities of other pesticides against newly hatching larvae were over 70% after 72 h. Compared to the newly hatched larvae, the toxicities of most pesticides on the third instar larvae decreased. The corrected mortalities of 11 pesticides, including 4.5% lambda-cyhalothrin EC, 1.8% abamectin ME, 20% chlorantraniliprole SC, 0.5% matrine AS, etc, were below 70% after 72 h for the third instar larvae. Eighteen pesticides which had good effects on the third instar larvae were selected to determine their toxicities on the fifth instar larvae. The results showed that except for 30% buprofezin·chlorpyrifos EC, 1.8% abamectin ME, 3.2% lambda-cyhalothrin·emamectin benzoate ME, 56% abamectin·propargite ME, 20% chlorantraniliprole SC and 10% flubendiamide SC, the corrected mortalities of 12 other pesticides against the fifth instar larvae were above 70%, including 6% emamectin benzoate·chlorfenapyr EC, 44% cypermethrin·profenophos EC, 25% profenophos·methomyl EC, 15% indoxacarb SC, 3 billion PIB·mL^-1 cabbage armyworm nuclear polyhedrosis virus SC, 25% emamectin benzoate·chlorbenzuron SC, 2% emamectin benzoate ME, 45% chlorpyrifos EC, 34% spinetoram·methoxyfenozide SC, 5% lufenuron EC, 40% fipronil·spinetoram WG, and 1% celastrus angulatus EC.