Oral toxicity of Photorhabdus luminescens and Xenorhabdus nematophila (Enterobacteriaceae) against Aedes aegypti (Diptera: Culicidae)
Oral toxicity of Photorhabdus luminescens and Xenorhabdus nematophila (Enterobacteriaceae) against Aedes aegypti (Diptera: Culicidae)
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DOI：
10.1007/s00436-013-3460-x
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发表时间：
2013-08-01
影响因子：
2
通讯作者：
Heermann, Ralf
中科院分区：
文献类型：
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作者：
da Silva, Onilda Santos;Prado, Geronimo Rodrigues;Heermann, Ralf
登革热是一种重要的媒介传播疾病，主要由埃及伊蚊传播。迄今为止，还没有针对这种虫媒病毒疾病的疫苗或有效药物。由于控制蚊子实际上是控制登革热的唯一方法，因此需要探索其他具有成本效益的虫害控制策略。革兰氏阴性肠道细菌Xabridus和Photorhabdus与线虫寄生虫共生，线虫寄生虫本身对昆虫幼虫具有高致病性。在这里，我们评估这些昆虫病原细菌的口服毒性在A。埃及伊蚊幼虫幼虫（第三晚或第四早龄）的敏感性进行了评估，通过将它们暴露于悬浮液中含有Photorhabdus luminescens或Xcadhabdus philophila，分别。两种饮食处理进行了测试，幼虫喂养宠物食品和未喂养的幼虫。24 h后，幼虫开始死亡。暴露于发光拟单胞菌分别杀死了73%的进食幼虫和83%的未进食幼虫。相比之下，X.嗜热菌的致病性较低，在喂食处理中杀死52%的幼虫，在不喂食处理中杀死42%。值得注意的是，在将幼虫暴露于任何一种细菌物种后，在所有生物测定中均观察到同类相食。据我们所知，这是第一份证明这些昆虫病原细菌对口服A。埃及人的杀戮。我们的研究结果提供了一个有前途的基础上，使用这些细菌作为生物杀虫剂的蚊子控制在未来。
Dengue fever is an important vector-borne disease, mainly transmitted by Aedes aegypti. To date, there are no vaccines or effective drugs available against this arboviral disease. As mosquito control is practically the only method available to control dengue fever, alternative and cost-effective pest control strategies need to be explored. The gram-negative enteric bacteria Xenorhabdus and Photorhabdus are symbiotically associated with nematode parasites, which themselves are highly pathogenic for insect larvae. Here, we evaluate the oral toxicity of these entomopathogenic bacteria in A. aegypti larvae. The susceptibility of larvae (third late or fourth early instars) was assessed by exposing them to suspensions containing Photorhabdus luminescens or Xenorhabdus nematophila, respectively. Two diet treatments were tested with larvae fed on pet food and unfed larvae. After 24 h, larvae began to die when exposed to the bacteria. Exposure to P. luminescens killed 73 % of the fed and 83 % of the unfed larvae, respectively. In comparison, X. nematophila was less pathogenic, killing 52 % of the larvae in the fed and 42 % in the unfed treatment. Remarkably, cannibalism was observed in all bioassays after exposing larvae to either of the bacterial species. To our knowledge, this is the first report demonstrating the efficiency of these entomopathogenic bacteria for oral A. aegypti killing. Our results provide a promising basis for using these bacteria as bioinsecticides for mosquito control in the future.