4种植物源杀虫剂对枸杞棉蚜的防效试验

Efficacy of four botanical pesticides against Aphis gossypii on wolfberry

为筛选防治枸杞棉蚜的有效生物农药,降低化学农药使用量,本试验选择4种植物源杀虫剂:5%除虫菊素乳油、0.3%苦参碱水剂、1.5%除虫菊素水乳剂和6.0%鱼藤酮微乳剂,分别设置高、中、低3个浓度,以生产中常用化学杀虫剂25%噻虫嗪水分散粒剂为对照药剂,喷雾防治枸杞棉蚜。结果表明:在4种植物源杀虫剂中,以0.3%苦参碱水剂对棉蚜的防效最佳,该药剂300倍和500倍液在药后7 d防效分别达77.14%,72.38%,与对照药剂无极显著差异,其他3种生物农药的高、中剂量对枸杞棉蚜亦具有较佳防效,且所有处理在试验剂量范围内均对作物安全。推荐在枸杞棉蚜发生初期轮流、交替使用,以降低农残、延缓甚至避免害虫抗性的产生。

For screening of effective biological insecticides to prevent and control Aphis gossypii Glover on Chinese wolfberry,and reducing the use of chemical pesticides,four kinds of botanical pesticides including 5% pyrethrin emulsifiable concentrate(EC),0.3% matrine aqueous solution(AS),1.5% pyrethrin emulsion in water(EW) and 6.0% rotenone microemulsion(ME) were chosen,and the high,medium and low concentrations were set for each pesticide. The conventional chemical pesticide 25% thiamethoxam oxazine water dispersible granule(WDG) was used as a control to prevent Aphis gossypii by spraying. Test results showed that 0.3% matrine AS showed the best controlling efficiency. The efficacy of 300 and 500 times of the AS was 77.14% and 72.38% on the 7 th day after treatment,and there was no significant difference between the AS and the control treatment. The other botanical pesticides had better prevention effect at medium and high dose level. All treatment were safe for crop in the rang of experimental does.The four kinds of botanical pesticides can be used take turns,interchangeably at early stage of Aphis. gossypii,to reduce pesticide residues and delay or even avoid pest resistance.