有机磷杀虫剂对马铃薯腐烂茎线虫趋化性的影响

Effects of Different Organophosphorus Insecticides on the Chemotaxis of Ditylenchus destructor

[目的]研究有机磷杀虫剂对马铃薯腐烂茎线虫趋化性的影响。[方法]将马铃薯腐烂茎线虫浸渍在三唑磷、辛硫磷、毒死蜱、丙溴磷以及对照药剂阿维菌素不同质量浓度的药液中,24 h后用灭菌水清洗3次后加入1%水琼脂平板中央,36 h后观察记录线虫对灰葡萄孢菌、半裸镰刀菌、甘薯切片和马铃薯切片等不同引诱物的趋化性。[结果]质量浓度0.01～10 mg/L,线虫经三唑磷、辛硫磷和毒死蜱药液浸渍处理后仍表现出对灰葡萄孢菌的明显趋性,且由于药剂的毒物兴奋效应(Hormesis),引诱物上能诱集到更多的线虫。结果还表明:线虫经10 mg/L丙溴磷处理后,其各引诱物的引诱率明显高于对照,且对灰葡萄孢菌、甘薯和马铃薯的趋性在0.05水平上无显著性差异。[结论]三唑磷、辛硫磷、毒死蜱及对照药剂阿维菌素在低质量浓度下对马铃薯腐烂茎线虫的趋化性无影响,10 mg/L丙溴磷处理线虫后,其趋化性发生改变。

The objectives of this study were to analyze the effect of organophosphorus insecticides on the chemotaxis of Ditylenchus destructor.[Methods]Nematodes were incubated in insecticides solution for 24 h,subsequently washed three times each and then were placed to the centre of 9 cm diameter petri dish which contained 1% agar base.The attractions,including Botrytis cinerea,Fusarium semitectum,potatoes cutting and sweet potato cutting,were placed at equal distance from the centre.After incubation for 36 h,nematodes were isolated and counted.[Results]Chemoreceptive response of nematodes to Botrytis cinerea were maintained when nematodes were treated with low concentration（0.01-10 mg/L） of triazophos,phoxim and chlorpyrifos.The numbers of nematode collected from attractions were much more than that of control for the hormesis phenomenon of insecticides.The results also showed that the attractive rate of attractions were higher than that of control after 10 mg/L profenofos treatment and attractive rate of B.cinerea was not significantly different from that of potatoes and sweet potato when nematodes were treated with 10 mg/L profenofos（P0.05）.[Conclusions]Low concentration of triazophos,phoxim,chlorpyrifos and control had no effect on the chemotaxis of D.destructor,and 10 mg/L profenofos exposure leaded to the alteration of the chemotaxis of D.destructor.