昆虫病原线虫对暗黑鳃金龟的致病力

Virulence of Entomopathogenic Nematodes to Holotrichia parallela Larvae

为了筛选防治暗黑鳃金龟Holotrichia parallela的优良昆虫病原线虫品系,本文通过室内生测,比较了7个昆虫病原线虫品系对暗黑鳃金龟1龄末幼虫的致病力,并明确了其最佳侵染条件。生测结果表明,不同昆虫病原线虫品系对暗黑鳃金龟1龄末幼虫均有一定的致病力,其中樱桃异小杆线虫Heterorhabditis bacteriophora(D26-6)对暗黑鳃金龟幼虫致病力最强,在处理9 d后,暗黑鳃金龟幼虫的校正死亡率达到了100%。此外,温度、土壤湿度以及线虫施用剂量对D26-6线虫的致病力均会产生一定的影响,其侵染暗黑鳃金龟幼虫的适宜温度为25℃、适宜土壤含水量为18%;当暗黑鳃金龟幼虫与D26-6线虫比为1:100时,处理11 d后暗黑鳃金龟幼虫的校正死亡率可达到100%。

The pathogenicity of seven entomopathogenic nematodes(EPNs)against the late 1st instar larvae of Holotrichia parallela was tested in laboratory to screen the effective strains of entomopathogenic nematodes for the H.parallela control,and the most suitable environmental conditions of strains were identified.Results showed that pathogenicity of seven EPNS strains were different under laboratory conditions,the Heterorhabditis bacteriophora(D26-6)had the strongest pathogenicity to the larvae of H.parallela.In addition,temperature,soil moisture and dosage of EPNs all take effects on the pathogenicity.The optimum temperature and soil moisture for H.bacteriophora(D26-6)infection were 25℃and 18%respectively,when the ratio of H.parallela larvae to D26-6 nematodes was 1:100,the mortality of H.parallela larvae can reach 100%after 11 days.