小菜蛾对杀虫双的抗药性监测、交互抗性测定及药剂防治研究

MONITORING ON THE RESISTANCE OF DIAMOND BACK MOTH, Plutella xylostella L. TO DIMEHYPO AND CROSS RESISTANCES TO DIMEHYPO RESISTANT STRAIN,AND STUDY ON FIELD CONTROL EXPERIMENTS

抗药性监测结果表明，三年来贵阳小菜蛾种群对杀虫及的抗性增长２３．５倍；其余各地种群仍有较高的敏感性；对敌敌畏各地种群仍有较高的敏感性，抗性不明显；对溴氰菊酯贵阳、安顺种群产生了高度抗性，与敏感品系比较抗性分别增长１１２４倍和５５８倍，其余各地种群对溴氰菊６８仍有较高的敏感性，抗性不明显。交互抗性测定结果表明：抗杀虫双品系对同类药剂杀螟丹有明显的正交互抗性；对敌敌畏、溴氰菊酯、灭多威和苏云金杆菌等的敏感度较高。田间防治试验结果表明，杀虫双仍有较高的防治效果，苏云金杆菌和螨虫素与杀虫双混用可明显提高防治效果。

In 1991 and 1993, two bioassays for insecticide toxicity were made to study the resistance changes of diamond back moth which were collected from six main vegetable production areas including Guiyang, Zunyi,Anshun, Duyun, Tongren and Bijie of Guizhou Province. The results indicated; within the three years,Guiyang strain increased the resistance to dimehypo as much as 32.5 times, the other strains showed high sensitivity to this insecticide. All six strains were highly sensitive to DDVP. The two strains of Guiyang and Anshun produced very high resistance to deltamethrin and their resistances went up to 1124 and 558 folds,and other strain had no remarkable resistance. The cross resistances of dimehypo resistant strain(the 30th and 70th generations selected in laboratory)were revealed by bioassays made in 1991 and 1994. The result showed that the resistant strain showed significant positive cross resistance to the same type of insecticides such as cartap, light posistive or negative resistances to DDVP (organophosphorus), deltamethrin (pyrethroids),methomyl (carbamate),and Bt (microbic insecticide). The field control experiments demonstrated that dimehypo had a comparatively satisfied effect and mixing this insecticide with Bt or abametin could control diamondback moth better.