广州、深圳地区小菜蛾对定虫隆、Bt 的抗性监测

MONITORING OF INSECTICIDE RESISTANCE IN DIAMONDBACK MOTH,PLUTELLA XYLOSTELLA(L.)TO CHLORFLUAZURON AND BACILLUS THURINGIENSIS IN GUANGZHOU AND SHENZHEN

采用 Potter's 喷雾塔喷雾的方法测定广州和深圳菜区小菜蛾对儿丁质合成抑制剂定虫隆、氟虫脲、伏虫隆、氟铃脲的抗药性。结果表明,深圳菜区小菜蛾对定虫隆产生明显抗性,1990年11月测定抗性倍数为15.0,1991年12月为70.9,对氟虫脲、伏虫隆、氟铃脲具有不同程度交互抗性,抗性倍数分别为26.7,15.5 和5.8。广州菜区小菜蛾对以上药剂均未产生抗性(抗性倍数最高为2.8)。采用浸渍法测定小菜蛾对苏云金杆菌 Bt 抗性的结果表明,深圳菜区小菜蛾对 Bt 的抗性逐年提高,1990年12月测定的抗性倍数为21.1,1991年12月为26.9,1992年3月为35.0,广州菜区小菜蛾具有强的耐药性或低抗药性,抗性倍数8—9。

Insecticide resistance in diamondback moth(DBM),Plutella xylos-tella(L.)to chlorfluazuron and Bacillus thuringiensis(Bt)was monitoredby spray and immersion method respectively,during 1990-1992 in Gu-angzhou and Shenzhen regions.Results showed that DBM collected fromShenzhen was 15-fold in 1991 and 71-fold resistance to chlorfluazuronin 1992 as compared with S strain,and had cross-resistance to flufeno-xuron(26.7-fold),teflubenzuron(15.a-fold),hexafluron(5.8-fold),nosignificant resistance was found to these insecticides in DBM collectedfrom Guangzhou.Resistance ratioof DBM to Bt increased from 21.1 to35.0 in Shenzhen and kept at 8-9 in Guangzhou during 1990-1992.