The study aimed to evaluate the efficacy of the EPNs against the larvae of Egyptian cotton leaf worm Spodoptera littoralis (Boisduval) and the black cutworm Agrotis ipsilon (Hufnagel) (Lepidoptera: Noctuidae) in vitro before in vivo study. The susceptibility of both larval species to the entomopathogenic nematode species, Steinernema monticolum and Heterorhabditis bacteriophora, was evaluated under laboratory conditions. The concentration of 400 IJs/dish for S. monticolum achieved up to 97.77 and 95.55% mortality rates of the 5 larval instars from 2nd to 6th instars of S. littoralis and A. ipsilon, respectively after 72 h. The concentration of 800 IJs/dish recorded larval mortality rates of 41.86 to 100% against 2nd to 6th instars of A. ipsilon larvae, after 72 h. At the lowest concentration (50 IJs/dish), the larvae of S. littoralis were more susceptible to H. bacteriophora than the larvae of A. ipsilon. The data indicated that 200 IJs/dish was the most effective concentration for all larval stages of both insect pests because the mortality percentage was 100%.

中文翻译：

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昆虫病原线虫对斜纹夜蛾（Boodd。）和伊格隆农杆菌（H。）（鳞翅目：夜蛾科）的功效

这项研究旨在在体内研究之前在体外评估EPNs对埃及棉叶蠕虫斜纹夜蛾（Boisduval）和黑鳞虫Agrotis ipsilon（Hufnagel）（鳞翅目：夜蛾科）的幼虫的功效。在实验室条件下，评估了两种幼虫对昆虫病原线虫物种，Steinernema monticolum和Heterorhabditis细菌的敏感性。在72小时后，山链球菌的400 IJs /皿的浓度分别使滨海链球菌第二和第六龄的5龄幼虫的死亡率分别达到97.77和95.55％。在72 h后，相对于Ipsilon幼虫的2至6龄幼虫，800 IJs /皿的浓度记录的幼虫死亡率为41.86至100％。在最低浓度（50 IJs /皿）下，S的幼虫。滨藜比拟南芥的幼虫更容易受到细菌的感染。数据表明，对于两种害虫的所有幼虫阶段，200 IJs /皿是最有效的浓度，因为死亡率为100％。