炔螨特等5种杀螨剂防治苹果红蜘蛛田间药效试验

Field Trials of Five Acaricides against Panonychus ulmi(Koch)

测定了5种不同作用机理杀螨剂对苹果树红蜘蛛的防效,并对其田间的应用效果进行评价。结果表明:73%炔螨特乳油和20%甲氰菊酯乳油速效性较好,药后2d防效即达到79%以上,但持效期相对较短;500g/L四螨嗪悬浮剂、80%苯丁锡水分散粒剂和5%噻螨酮乳油速效性一般,但持效期较长,药后25d防效仍能维持在90%以上。炔螨特、四螨嗪、苯丁锡、噻螨酮4种不同作用机制的杀螨剂对天敌和作物安全,交替使用能有效控制红蜘蛛为害,降低产生抗性的风险;甲氰菊酯为广谱性杀虫剂,不宜作为专用杀螨剂使用。

In this paper, five acaricides with different mechanisms were conducted against Panonychus ulmi through field trail and the application effects were evaluated. The results showed that 73% propargite EC and 20% fenpropathrin EC had a quick bioactivity and significant effect on P. ulmi with the control efficacy over 79% at second day after the treaments, but the effective period was no more than 14 days. 500 g/L elofentezine SC, 80% fenbutatin oxide WG and 5% hexythiazox EC had a slow bioactivity but an effective period of more than 25 days in the fields with the control efficacy over 90%. Alternative use of propargite, clofentezine, fenbutatin oxide and hexythiazox could control P. ulmi timely and effectively and were safe on natural enemies and crops. It can also reduce the risk of pesticide tolerance. Therefore, they were worth to select priority in the field use. Propargite is a kind of broad spectrum insecticide, but it is not suitable to use as a special acaricide.