Overmyer Jay P, Stephens Marianne S, Gray Elmer W, Noblet Ray
Department of Entomology, University of Georgia, 413 Biological Sciences Building, Athens, GA 30602, USA.
J Am Mosq Control Assoc. 2006 Mar;22(1):135-9. doi: 10.2987/8756-971X(2006)22[135:MTEOTG]2.0.CO;2.
The green alga Scenedesmus quadricauda has been shown to decrease the efficacy of Bacillus thuringiensis var. israelensis (Bti) to black fly larvae in laboratory experiments. In this study, 2 approaches to mitigating the effects of S. quadricauda were tested, increasing the dose of Bti exposed to the larval black flies and increasing the length of the exposure period. Results showed that increasing the dose as well as increasing the exposure time were effective methods for mitigating the effects of S. quadricauda on Bti efficacy. Assessment of larval mortality at different exposure periods to Bti indicate that the manifestation of toxicity or acquisition of toxic doses of the Bti formulation takes place approximately 2-3 times slower when S. quadricauda is present. These results provide information that might be useful in developing a plan of action to combat this complex situation in field operations.
在实验室实验中，已证明绿藻四尾栅藻会降低苏云金芽孢杆菌以色列变种（Bti）对黑蝇幼虫的防治效果。在本研究中，测试了两种减轻四尾栅藻影响的方法，即增加暴露于黑蝇幼虫的Bti剂量以及延长暴露时间。结果表明，增加剂量和延长暴露时间都是减轻四尾栅藻对Bti防治效果影响的有效方法。对不同暴露时间下Bti处理的幼虫死亡率评估表明，当存在四尾栅藻时，Bti制剂毒性的显现或有毒剂量的获取大约要慢2至3倍。这些结果为制定行动计划以应对野外作业中的这种复杂情况提供了可能有用的信息。
