Earthworms enhance soil structure, the decomposition of organic matter and the dissemination of beneficial soil organisms such as the entomopathogenic nematodes (EPNs). Nevertheless, the effects of earthworm feeding behavior or cutaneous excreta (CEx) on the performance of EPNs as biological control agents is poorly understood. We hypothesized that the presence of earthworms or their excreta reduces EPN fitness, measured in terms of pathogenicity and reproductive success. In laboratory experiments we first evaluated the killing ability of EPNs against Galleria mellonella (Lepidoptera: Pyralidae) larvae when inoculated in autoclaved soil alone or in combination with the earthworm Eisenia fetida (Haplotaxida: Lumbricidae) or their excreta. We also evaluated EPN efficacy and reproduction when exposed to CEx derived from E. fetida at two nematode concentrations (1.5 and 10 IJs/cm²). For both experiments, we tested four steinernematids (Steinernema carpocapsae, S. feltiae, S. glaseri, and S. khuongi) and two heterorhabditids (Heterorhabditis bacteriophora and H. zealandica). The presence of earthworms or their excreta resulted in significant reduction of the larval mortality caused by some of the steinernematids at certain timings depending of the species (P < 0.015), while heterorhabditids were mainly not affected. Both S. feltiae and H. zealandica progeny production was significantly reduced (P < 0.01) when exposed to CEx. Hence, we showed that the presence of CEx might alter the biocontrol performance of certain EPN species, especially steinernematids bigger than 600 μm in size (S. feltiae, S. glaseri, and S. khoungi), by affecting their pathogenicity and reproductive success.

enhance增强土壤结构，有机物的分解以及有益土壤生物的传播，例如昆虫病原线虫（EPNs）。但是，人们对understood的摄食行为或皮肤排泄物（CEx）对作为生物防治剂的EPNs性能的影响知之甚少。我们假设that的存在或它们的排泄物会降低EPN的适应性（以致病性和生殖成功率衡量）。在实验室实验中，我们首先评估了EPNs单独或与withEisenia fetida组合接种在高压灭菌的土壤中时对黑麦草幼虫（鳞翅目：Pyralidae）幼虫的杀灭能力。（Haplotaxida：Lumbricidae）或它们的排泄物。我们还评估了当暴露于两种线虫浓度（1.5和10 IJs / cm ²）的源自大肠杆菌的CEx时，EPN的功效和繁殖能力。对于这两个实验，我们测试了四个类固醇（Steinernema carpocapsae，毡状链球菌，glaseri和S. khuongi）和两个异种生殖器（Heterorhabditis bacteriophora和H. zealandica）。or或其排泄物的存在导致某些类群的类固醇类动物在某些时间导致幼虫死亡率的显着降低（P  <0.015），而异种生殖主要不受影响。两种S.和H. zealandica后代产量显著减少（P 当暴露于对比实施例<0.01）。因此，我们表明CEx的存在可能通过影响某些EPN物种的致病性和繁殖成功而改变它们的生物防治性能，特别是大小大于600μm的类神经炎线虫（S. feeliae，S。glaseri和S.khoungi）。