玉米截形叶螨药剂防治试验

EXPERIMENTAL STUDIES ON THE CONTROL OF Tetranychus trancatus EHARE ON CORN

室内毒力试验表明,1.8%爱福丁对截形叶螨雌成螨的毒力最高,LC50仅为0.0004mg/ml,其次为24.5%螨绝光(0.0022mg/ml)和24.5%螨极力(0.0056mg/ml),再次为45%混剂Ⅰ(0.0545mg/m1)和20%灭扫利(0.0564mg/m1),最差为40%氧乐果,LC50高达0.2394mg/ml,为1.8%爱福丁的598倍。室内杀卵试验表明,5%尼索朗杀卵作用最强,卵孵化率仅为0.34%(4000倍液);螨绝光仅次于尼索朗,卵孵化率为1.02%(2000倍液):再次为12.5%混剂Ⅱ,卵孵化率为12.51%(2000倍液);40%久效磷效果最差,卵孵化率高达48.33%(2000倍液)。田间药效试验表明,混剂Ⅰ和混剂Ⅱ防效最好,其次为螨绝光,但所有处理15d后,螨量基本恢复到原有水平。综合成本和防效考虑,建议在生产上使用混剂I2000倍液或螨绝光2000倍液。

A series of laboratory experiments were carried out to test the toxicity of insecticides against the femalea dults of Tetranychus trancatus Ehare. The results showed that the Abamectin was the most toxic (LC_(50):0.0004mg/ml), Manjueguang (LC_(50):0.0022mg/mi) and Manjili(LC_(50):0.0056mg/ml) was the second, Mixed solution I (LC_(50):0.0545mg/ml) and Fenpropathrin (LC_(50):(0.056 4)mg/ml) the third,and the Omethoate (LC_(50):0.2394mg/ml) the least. The toxicity of Hexythiazox against the eggs of T. trancatus was the most and the rate of hatchability was only 0.34% with its 4000X dilution. The secondly was Manjueguang and the rate of hatchability was 1.02% with its 2000X dilution. The thirdly was Mixed solution II and the rate of hatchability was 1.02% with its 2000X dilution. The least was Monocrotophos and the high rate of hatchability was 48.33% with its 2000X dilution. The field experiment showed that the control effects of Mixed solution Ⅰ and Ⅱ were the best, and Mjueguang was the second, but the mite populations renewed to the beginning level in 15 days in all the treatments. Considering both control effect and cost, Mixed solution Ⅰ and Manjueguang with 2000X dilution were recommended to use in practice.