【摘要】 <正> 抗药性是生物界的一种普遍现象,从昆虫的遗传变异来讲,长期使用一种化学农药,最终必将使昆虫产生抗药性。赤眼蜂的大量繁殖和利用,对害虫的防治、减少化学农药对环境的污染、降低害虫的防治成本,已经开辟了广阔的前景,深受人们欢迎。如果赤眼蜂对杀虫剂产生抗性,对协调生物防治和化学防治,必将带来更为良好效果。本试验从1983年6月开始至1985年10月的两年半时间里,用8种杀虫剂对稻螟赤眼蜂卵、蛹和成虫三个发育期分别进行连续处理。探讨赤眼蜂抗性品系培育方法和初步阐明那些药剂对赤眼蜂较易形成抗性,为害虫综合防治提供更为光明的前途。更多还原

【Abstract】 Based on the laboratory experiments of tolerance of Trichogramma japonicum to 23 kinds of pesticides in 1983,we conducted tests on the possibility of selection for insecticide—resistant strain of T. japonicum during 1983～1985 with 8 kinds of pesticides (metaphos、 tamaron、dimehypo、dimecron、mipcin、fenvalerate、decis and BHC).Tests were carried out on 3 developmental stages of parasite: egg、pupae(both in the eggs of rice grain moth)and adult. The stock culture was collected from the suburb of Guangzhou.The results showed that the resistant strain of T. japonicum to pyrethroid pesticides was easilierly selected, even if in common it was difficult for Trichogramma than for predatory mites. In egg stage, after 20 generations with 11 treatments, a 2.49 fold increase of LC50 in resistance to fenvalerate was observed, but in adult stage-only 0.94 fold. To decis, it was 1.78 and 1.80 fold increase in agg and pupal stage, respectively. To tamaron, it was 1.17 fold in- crease in resistance to adult stage, but in pupal stage, it was 0.63 fold decrease. Generally, the egg stage appeared more resistant to insecticides,than pupal stage and the adult stage was the most susceptible.In comparison with the LC50 of usually used concentration in the field, the LC50 of fenvalerate for egg stage of resistant strain increased by 6.40 times, LCS0 of decis by 4.03 times, LC50 of tamaron by 1.62 times, LC50 of dimecron by 0.82 times. The mechanism of insecticide-resistance for T.japonicum and tile competition of resistant strain with susceptible ones in the field will be investigated furthers.更多还原