Comparison between corn leaf aphid Rhopalosiphum maidis Fitch (Hemiptera: Aphididae) endosymbiotic microbiome and soil microbiome diversity under different management and climate

The<b> </b>corn leaf aphid, <i>Rhopalosiphum maidis</i> Fitch (Hemiptera: <i>Aphididae</i>), microbial symbiont and nine soil type microbial diversity, where maize are cultivated were genetically analyzed, along a gradient of maize management systems, that includes three different crop control strategies from three climatic regions. The central point of interest was to assess whether any similarity could be detected between the corn leaf aphid's rapid distribution increase throughout mainland Europe and variation in its endosymbiont microbiome diversity. According to the results, significant positive relationships between some symbiont bacterial species and climate conditions were detected, including increases in the abundances of two secondary (or facultative) symbiont species, <i>Serratia symbiotica</i> and <i>Wolbachia </i>spp.<i> </i>under extreme climate conditions (high and low temperatures), whereas only a low abundance of the obligate primary symbiont, <i>Buchnera aphidicola</i> was observed under these same climate conditions. Less effects of soil types were detected. Our study comprises the first comprehensive analyses about a pest aphid and its associated symbiont fauna in relation to ambient temperature conditions, and as such, we believe may well help in the development of new control strategies.

本研究对玉米叶蚜（corn leaf aphid，学名<i>Rhopalosiphum maidis</i> Fitch，隶属于半翅目（Hemiptera）蚜科（Aphididae））、其微生物共生体以及种植玉米的农田中9种土壤类型的微生物多样性，沿着覆盖三个气候区的三种不同作物防控策略的玉米管理系统梯度开展了遗传学分析。本研究的核心目标为评估玉米叶蚜在欧洲大陆的快速分布扩张与其内共生微生物组（endosymbiont microbiome）多样性的变异之间是否存在相关性。研究结果显示，部分共生细菌类群与气候条件存在显著正相关关系：在极端气候（高低温）条件下，两种次生（兼性）共生菌——粘质沙雷氏菌（<i>Serratia symbiotica</i>）和沃尔巴克氏体属（<i>Wolbachia</i> spp.）的丰度显著升高；而在相同极端气候条件下，专性初生共生菌（obligate primary symbiont）<i>Buchnera aphidicola</i>的丰度仅处于较低水平。土壤类型对该系统的影响相对较弱。本研究是首个针对害虫蚜虫及其相关共生菌群与环境温度条件的综合性分析，我们认为该研究可为新型害虫防控策略的开发提供有力支撑。