Department of Entomology, Cornell University, Ithaca, NY 14853-2601, USA.
Department of Biological Sciences, University of New Hampshire, Durham, NH 03823, USA.
Curr Opin Insect Sci. 2019 Jun;33:77-83. doi: 10.1016/j.cois.2019.03.006. Epub 2019 Apr 3.
Many insect species derive fitness benefits from associations with defensive microbial symbionts that confer protection against pathogens and parasites. These relationships are varied and diverse, but a number of studies highlight important trends. The effects of defensive symbionts can be context-dependent and influenced by variable selection imposed by the organism against which the symbiont protects. Additionally, genetic variation in both hosts and symbionts can greatly influence the outcome of these interactions. Here, we describe interactions between siricid woodwasps, their fungal symbionts and parasitic nematodes and show how defense by symbionts in this system is also context-dependent. The species or strain of the white rot fungus used as a symbiont by Sirex can influence parasitism of these hosts by Deladenus nematodes.
许多昆虫物种从与防御性微生物共生体的关联中获得适应性益处，这些共生体提供了对病原体和寄生虫的保护。这些关系多种多样，但有许多研究强调了重要的趋势。防御共生体的影响可能取决于上下文，并受到生物体所面临的选择压力的影响。此外，宿主和共生体的遗传变异也会极大地影响这些相互作用的结果。在这里，我们描述了木蜂、它们的真菌共生体和寄生线虫之间的相互作用，并展示了这个系统中的共生体防御如何也是取决于上下文的。白腐真菌的种类或菌株，作为 Sirex 的共生体，可以影响 Deladenus 线虫对这些宿主的寄生。
