蒜和葱上二斑叶螨的发生为害及其抗药性监测

二斑叶螨寄主植物范围极广, 但其对百合科蔬菜造成危害的研究报道极少?本研究采集了来自北京海淀百合科蔬菜蒜和葱上的2个二斑叶螨种群, 生物测定结果显示, 2个种群对阿维菌素呈现出极高水平抗性, 对哒螨灵为中等以上抗性(LC50>5 000 mg/L), 对新型药剂联苯肼酯?虫螨腈和腈吡螨酯也表现出中等到高水平抗性?抗性基因突变频率检测发现, 与阿维菌素抗性相关基因G314D和G326E位点以及和哒螨灵抗性相关基因H92R位点的突变频率均高达100%, 为纯合抗性种群?因此, 本研究所测试的2个二斑叶螨种群对阿维菌素和哒螨灵单剂的敏感性极低, 需慎重选用这2种药剂, 而3种新型杀螨剂联苯肼酯?虫螨腈和腈吡螨酯在田间需轮换使用?

Occurrence and pesticide resistance of Tetranychus urticae on garlic and Chinese onion

Two-spotted mite has a wide range of host plants, however, its infestation on Liliaceae vegetables is rarely reported. In this study, two populations of Tetranychus urticae on Liliaceae vegetables, garlic and Chinese onion, were collected in Haidian, Beijing. Bioassays showed that the two populations had extremely high resistance to abamectin, moderate to high resistance to pyridaben (LC50 >5 000 mg/L), and moderate to high resistance to the novel pesticides, bifenazate, chlorfenapyr, and cyenopyrafen. The frequencies of the target-sites G314D and G326E mutations associated with abamectin resistance and the target-site H92R associated with pyridaben resistance were up to 100%, indicating the two populations are homozygous-resistant. Therefore, the susceptibilities of the two tested T. urticae populations to the single agents of abamectin and pyridaben are extremely low, and the three novel pesticides including bifenazate, chlorfenapyr, and cyenopyrafen should be rotated carefully in the field.