Laboratory of Entomology and Applied Zoology, Department of Agriculture, Crop Production and Rural Environment, University of Thessaly, Phytokou str., Nea Ionia 38446, Magnissia, Greece.
J Econ Entomol. 2010 Jun;103(3):977-84. doi: 10.1603/ec09202.
The insecticidal effect of Heterorhabditis bacteriophora Poinar (Nematoda: Heterorhabditidae), Steinernema carpocapsae (Weiser) (Nematoda: Steinernematidae), and Steinernema feltiae (Filipjev) (Nematoda: Steinernematidae) against Mediterranean flour moth, Ephestia kuehniella (Zeller) (Lepidoptera: Pyralidae) (larvae), lesser grain borer, Rhyzopertha dominica (F.) (Coleoptera: Bostrychidae) (adults), rice weevil, Sitophilus oryzae (L.) (Coleoptera: Curculionidae) (adults), and confused flour beetle, Tribolium confusum Jacquelin du Val (Coleoptera: Tenebrionidae) (adults and larvae) was examined under laboratory conditions in wheat, Triticum aestivum L. The nematodes were applied at the following doses: 0 (control), 100, 500, 1,000, 1,500, 5,000, 10,000, and 20,000 infective juveniles (IJs) per ml, corresponding to 10, 50, 100, 150, 500, 1,000, and 2,000 IJs per insect, and their infectivity was tested at 20 and 30 degrees C after 4 and 8 d of exposure. For E. kuehniella larvae wheat treatments with S. feltiae provided mortality that ranged from 36.7 to 78.3% whereas no mortality was noted in the treatment with S. carpocapsae at 100 IJs per ml at 20 or at 30 degrees C. Also, at 20 degrees C, in wheat treated with H. bacteriophora at 100 IJs per ml, very few larvae were dead. For R. dominica adults, at 20 degrees C, the mortality of adults in wheat treated with S. feltiae and S. carpocapsae did not exceed 23.3 and 41.7%, respectively, at 20,000 IJs per ml, with no significant differences among doses. In the case of S. oryzae adults, the mortality was very low at all doses, and temperatures and did not exceed 9%. Mortality of T. confusum adults did not exceed 17% regardless of the entomopathogenic nematode species tested. In contrast, mortality of T. confusum larvae was notably higher and exceeded 56% in wheat treated with 10,000 or 20,000 IJs per ml of S. feltiae at 20 degrees C. Unlike S. feltiae and S. carpocapsae, the application of H. bacteriophora resulted in lower mortality levels. Generally, the increase of temperature reduced the mortality levels of the T. confusum larvae. In most cases, the efficacy level of the tested entomopathogenic nematode species increased with the dose and decreased with the increase of temperature.
在实验室条件下，将嗜虫异小杆线虫（ Heterorhabditis bacteriophora Poinar）（线虫：异小杆科）、斯氏线虫（ Steinernema carpocapsae ）（线虫：斯氏科）和红孢拟久斯线虫（ Steinernema feltiae ）（线虫：斯氏科）对地中海粉螟（ Ephestia kuehniella ）（鳞翅目：螟蛾科）（幼虫）、玉米象（ Rhyzopertha dominica ）（鞘翅目：象甲科）（成虫）、米象（ Sitophilus oryzae ）（鞘翅目：象甲科）（成虫）和赤拟谷盗（ Tribolium confusum Jacquelin du Val ）（鞘翅目：拟步甲科）（成虫和幼虫）进行了检测。在小麦（ Triticum aestivum L.）中以以下剂量施用线虫：0（对照）、100、500、1000、1500、5000、10000 和 20000 条感染性幼虫（ IJ ）/毫升，相当于每只昆虫 10、50、100、150、500、1000 和 2000 IJ ，并在暴露后 4 天和 8 天在 20 和 30°C 下测试其感染性。对于地中海粉螟幼虫，在小麦中处理斯氏线虫的死亡率范围为 36.7%至 78.3%，而在 20°C 时，每毫升 100 IJ 的斯氏线虫处理中未观察到死亡率。同样，在 20°C 下，在每毫升 100 IJ 的嗜虫异小杆线虫处理的小麦中，很少有幼虫死亡。对于玉米象成虫，在 20°C 下，在小麦中处理斯氏线虫和斯氏线虫的成虫死亡率分别不超过 23.3%和 41.7%，在每毫升 20000 IJ 时，剂量之间没有显著差异。对于米象成虫，在所有剂量和温度下，死亡率均非常低，不超过 9%。赤拟谷盗成虫的死亡率无论测试哪种昆虫病原线虫都不超过 17%。相比之下，在 20°C 下，在小麦中处理 10000 或 20000 IJ/ml 斯氏线虫的情况下，赤拟谷盗幼虫的死亡率明显更高，超过 56%。与斯氏线虫和斯氏线虫不同，嗜虫异小杆线虫的应用导致死亡率降低。通常，温度升高会降低赤拟谷盗幼虫的死亡率。在大多数情况下，测试的昆虫病原线虫物种的功效水平随剂量增加而增加，随温度升高而降低。
