Sheppard D C, Joyce J A
Department of Entomology, University of Georgia, Tifton 31793.
J Econ Entomol. 1992 Oct;85(5):1587-93. doi: 10.1093/jee/85.5.1587.
Lambdacyhalothrin cattle ear tags controlled horn fly, Haematobia irritans (L.), for 14 wks or longer during 1986-1988 in Georgia, USA. In 1989 and 1990, control of < 50 horn flies per side of cow was achieved for < or = 4 wk because of high levels of pyrethroid resistance in horn flies selected with lambdacyhalothrin. The highest resistance ratios (RRs) were seen in 1989. These were 498 for lambdacyhalothrin; 92,000 for fenvalerate; and 54 for permethrin. RRs for cypermethrin as high as 8,800 were estimated in 1990 when the RR for fenvalerate was only 1,060. No cross-resistance to diazinon was detected. These high levels of pyrethroid resistance seem to have a large component of metabolic resistance. Synergistic coefficients as high as 3,600 were determined by addition of nonlethal amounts of piperonyl butoxide. Resistance development in a no-pyrethroid-use area indicates movements of > or = 3km by sufficient numbers of horn flies can significantly change the RR.
1986 - 1988年期间，在美国佐治亚州，含有高效氯氟氰菊酯的牛耳标对角蝇（Haematobia irritans (L.)）的控制期长达14周或更长时间。1989年和1990年，由于用高效氯氟氰菊酯选育的角蝇对拟除虫菊酯产生了高水平抗性，每侧牛身上角蝇数量控制在50只以下的时间不足或等于4周。1989年出现了最高的抗性比率（RRs）。其中，高效氯氟氰菊酯的抗性比率为498；氰戊菊酯为92,000；氯菊酯为54。1990年，当氰戊菊酯的抗性比率仅为1,060时，氯氰菊酯的抗性比率估计高达8,800。未检测到对角硫磷的交叉抗性。这些高水平的拟除虫菊酯抗性似乎很大程度上是代谢抗性。通过添加非致死量的胡椒基丁醚测定的增效系数高达3,600。在一个未使用拟除虫菊酯的地区，抗性的发展表明，足够数量的角蝇移动3公里或更远的距离会显著改变抗性比率。
