大豆花叶病毒病对大豆蚜翅两型分化的影响研究

The soybean aphid (Aphis glycines), a native of Asia, has made serious damage to the soybean production world widely, since the recent introduction of the soybean into United States and some other European countries. In addition to the direct damage caused by the piercing sucking from A. glycines, the aphid also play an important role as vector for transmission of several plant virus, such as soybean mosaic virus (SMV), which could result in more server losses to the soybean yield. Wing polyphenism, which has been considered ecologically and evolutionarily critical is common in aphids. Data from field survey have demonstrated that, the happening of virus diseases were correlated to the emergence of alate aphid in the field. The “Vector Manipulation Hypothesis” speculated that pathogens could change the behavior of vectors for enhancing of their transmission. According to all mentioned above, we propose to do the research on the subject that plant viruses could manipulate aphid to broaden their spread by inducing more winged shaped offspring. The project is proposed to carry out in the interaction system composed of soybean aphid, soybean and SMV, through the detection of the development, alate incidence, and behavior change in the parthenogenesis population of A. glycines colonized on the diseased soybean host, compared to that on the mock treated host plants. The transmission status of SMV will also be tested to verify the speculation of the “Vector Manipulation Hypothesis”. The expecting results of the proposal may help us with further understanding about the impact of environmental factors on the wing polyphenism of aphid and the meaningful roles of “vector manipulation” in the ecological fitness and evolution, and also could offer theological suggestions for the broadcasting and management of A. glycines and SMV happened in the soybean field.

大豆蚜是世界范围内大豆生产上的害虫。除了直接为害，大豆蚜还是田间扩散和传播植物病毒的介体，可以造成病毒病的大面积发生，其为害更加严重。蚜虫具有翅两型分化的现象，而且调查结果发现植物病毒病的发生状况与有翅蚜的发生线性相关。“病原物操控传播介体假说”提出病原物可以通过“操控”介体的表型和行为改变来扩大其传播能力。鉴于此，本项目拟在申请人所在课题组关于蚜虫两翅型分化相关机理研究的基础上，采用为害严重并同时作为大豆害虫和大豆花叶病毒传播介体的大豆蚜、大豆及其花叶病毒这三者组成的互作系统为代表，以寄主染毒对孤雌生殖大豆蚜翅两型分化的影响作为研究切入点，通过对染毒寄主上蚜虫生长发育、行为变化及其对病毒扩散的影响等内容的研究，明确寄主植物病原物对介体蚜虫生长发育的影响，深化关于环境因子对蚜虫翅型分化影响的认识，探讨“病原物操控介体”的生态和进化意义，并为田间大豆病虫害的预测预报和防治提供理论指导。

大豆蚜是世界大豆生产中的重要害虫。除可直接吸食损伤，大豆蚜还可以传播大豆花叶病毒，造成更大的经济损失。为揭示大豆花叶病毒（SMV）与大豆蚜之间的生态互作关系，为大豆病虫害的综合治理提供依据，本项目以感病大豆品种1138、大豆蚜和大豆花叶病毒SC3株系的互作体系为研究对象，系统研究了取食染毒大豆植株对大豆蚜生长发育、繁殖力和子代有翅型孤雌胎生大豆蚜分化的影响以及SMV感染对大豆植株及大豆蚜体内营养物质含量与同化吸收的影响。.研究结果表明：1）取食染毒大豆植株对无翅型和有翅型孤雌胎生大豆蚜的虫体生长均表现出显著的抑制效果。染毒大豆植株上各发育阶段大豆蚜的体长、体宽、头壳宽、触角长、腹管长和尾片长均短于健康大豆植株上的大豆蚜。2）取食染毒大豆植株显著抑制大豆蚜的发育和繁殖力。除4龄若蚜外，染毒植株上无翅和有翅型大豆蚜的体重和发育历期均显著低于健康植株上大豆蚜。染毒植株上无翅型大豆蚜的繁殖前期缩短，总繁殖力和潜在繁殖力降低、成虫寿命缩短，种群繁殖速率降低、世代周期延长。取食染毒寄主对大豆蚜种群的存活率无显著影响。3）染毒大豆植株上子代有翅型孤雌胎生蚜的分化比例显著低于健康植株上的大豆蚜。4） 感染SMV会诱导大豆叶片内总蛋白质和可溶性糖含量的增加，糖蛋比在病毒接种后15-20天内显著高于健康大豆叶片。染毒植株上大豆蚜体内海藻糖含量自3龄若蚜后均显著高于健康植株上大豆蚜，但染毒大豆植株上2-3龄若蚜和成蚜体内总蛋白质含量均显著低于健康植株上大豆蚜，糖蛋比波动较大。取食染毒大豆植株后大豆蚜体内初生内共生菌水平受到显著抑制。. 本项目研究表明，大豆花叶病毒病对大豆蚜的生长发育、繁殖力和子代的翅型分化具有显著的抑制效果，病毒感染对寄主大豆植株体内营养物质组成及大豆蚜体内内共生菌水平的干扰可能参与SMV与大豆蚜之间的生态互作关系。本研究将为进一步解析SMV的传播特点提供理论数据并可为从病虫害复合体角度进行综合治理提供新思路。