局部施用斯氏线虫对黄曲条跳甲的控制效应

ON THE PARTIAL APPLICATION OF STEINERNEMA CARPOCAPSAE STRAIN A24 AGAINST STRIPED FLEA BEETLE PHYLLOTRETA STRIOLATA

斯氏线虫对黄曲条跳甲具有较好的控制效果,但由于其田间使用量较大,成本高,生产上无法推广应用。利用斯氏线虫在潮湿土壤生境中具有的主动搜索能力,提出条带式施用方法,不仅显著降低线虫用量,而且对黄曲条跳甲具有较好的控制效果。采用条带施用(条带宽约10cm,带间距22.5cm),可将线虫用量降低到17.5亿条/hm^2,对黄曲条跳甲幼虫的感染率在71.28％左右,防效为72.2％,且与全施无显著差异,并使黄曲条跳甲种群趋势指数Ⅰ值降为2.416,干扰控制指数为0.252。

The use of entomopathogenic nematode Steinernema carpocapsae (Weiser) strain A24 is reasonable to suppress the population of striped flea beetle Phyllotreta strialata (Fabricius) , but it has not been commercially used so far, owing to its too high dosage required and cost of control. In consideration with the fact that this nematode possesses initiative searching ability in wet soil habitat, a partial band application method was proposed and used on probation by the authors, attempting to save the cost and labor. The results showed that as the spray band and blank space between spray bands were 10 and 22.5 cm wide, respectively, the nematode amount required had been reduced to 1.75 billion individuals/hm2 ; by this dosage treated, 71.28% of the larval P. strialata were infected , the control effect attained to 72.2% , the index of population trend went down to 2.416, and the interference index of population control was 0.252, which were all similar to those of whole bed spraying treatment.