昆虫共生体对不利温度的响应
Responses of insect holobionts to unfavorable temperatures

昆虫及其体内所包含的共生菌组成了昆虫共生体.温度是影响昆虫及其体内共生菌最为明显的一个环境因子,不仅可以直接影响昆虫,还通过其体内的共生菌间接影响寄主昆虫.昆虫共生菌种类多样,功能不一,其对不利温度的响应具有复杂性.有些共生菌能够协助寄主昆虫抵抗不利温度,增强寄主对环境的适应性;但也有共生菌在不利温度胁迫下含量会降低甚至消失,进而导致寄主昆虫对不利温度的抵抗力下降.本文综述了蚜虫、粉虱等昆虫体内各种共生菌对不利温度的不同响应,重点探讨了共生菌在高温下对寄主昆虫的保护作用与机理,以及某些共生菌对高温敏感并削弱寄主昆虫适应性的内在原因.昆虫与其体内共生菌共同应对环境的变化,今后应当将其作为一个多生物组成的整体进行研究.
Insects and their symbionts compose holobionts. Temperature is one of the most influential environmental factors affecting insects and their symbionts, acting both directly on the host insects and indirectly via symbionts. Responses of insect symbionts to unfavorable temperatures are complex and diverse on account of different roles and the variety of symbionts. Some symbionts may facilitate host adaptation to severe environment through the increase of tolerance to unfavorable temperatures. Other symbionts may decrease or even disappear under unfavorable temperatures, and in turn the capacity of insects to tolerate unfavorable temperatures may be reduced. In this article, the differential responses of various symbionts to unfavorable temperatures in aphids, whiteflies and other insect holobionts were reviewed. The protective effect and mechanisms of some symbionts to host insects under high temperatures, and the underlying causes of heat sensitivity of certain symbionts which in turn reduced the adaptation of host insects were discussed emphatically. This review indicates that insects and their symbionts have close relationships and confront the environment together, and thus insects are better to be explored as multi-organisms in future studies.