大豆孢囊线虫ISSRs标记的分子多样性及遗传分化

Soybean cyst nematode (SCN) is one of the most serious diseases in soybean production area in China, resulting in a great loss of the yield and quality of soybean. It has been a bottleneck that restricting the development of soybean industry in China. The molecular diversity and genetic divergence of Heterodera glycines will be researched among 150 cysts and J2 from 30 geographical populations of soybean plant areas in China by the ISSRs in this study. It will be revealed that how genetic variation and geographical pattern of populations of H.glycines to spread and diffuse, and that the disease to spread in China, in order to be clarified with the genetic divergence of the different geographic populations, the mechanism of diffusion of H.glycines, and the source of the genetic divergence of H.glycines in China, so as to be controlled and managed with the disease by the sustainable methods eventually. The technological platform for the analysis of the genetic diversity and hereditary constitution of plant nematodes established will be provided with the technical support for genetic variation of different geographic populations of plant parasitic nematodes and the theoretical basis of the mechanism of spread and diffusion of H.glycines if this study will be completed. Then the basis of the comprehensive control strategies for H.glycines will be formulated and the development of the soybean production will be promoted because of this study.

大豆孢囊线虫(SCN)是我国大豆产区最严重的病害之一，严重影响大豆的产量和品质，已成为制约我国大豆产业发展的瓶颈。本研究选用ISSRs分子标记技术，将从核DNA水平研究中国境内大豆孢囊线虫30个不同地理的150个个体群体内及群体间的遗传多样性及遗传分化水平，以揭示大豆孢囊线虫传播与扩散过程中种群的遗传变异及地理格局，并对该病害在我国的传播扩散方式进行推测，从而阐明大豆孢囊线虫在中国的传播与扩散机制，明确其不同地理种群产生遗传分化的原因，为大豆孢囊线虫病的可持续控制提供理论依据。该项目的完成将为植物线虫的遗传多样性及遗传结构分析建立技术平台，为探索植物寄生线虫不同地理种群的遗传变异提供技术支持，为明确大豆孢囊线虫的传播与扩散机制提供理论依据，为制定大豆孢囊线虫病的综合防治策略、促进中国大豆产业的发展奠定基础。

大豆孢囊线虫(SCN)是我国大豆产区最严重的病害之一，严重影响大豆的产量和品质，已成为制约我国大豆产业发展的瓶颈。本研究选用ISSRs分子标记技术，将从核DNA水平研究中国境内大豆孢囊线虫17个省市的不同地理的150个个体群体内及群体间的遗传多样性及遗传分化水平。结果表明，筛选出3个ISSR引物可获得大豆孢囊线虫ISSR分子标记清晰图谱，共得到58条谱带，其中50条为多态性条带，多态性条带百分率达到86.21%；遗传多样性分析表明不同种群间的多态性位点百分率（P）为84.48%，平均观测等位基因数（Na）为1.8848，平均有效等位基因数（Ne）为1.3419，平均期望杂合度（He）为0.2106，Shannon’s信息指数（I）为0.3308，遗传分化和遗传变异分析表明各种群之间遗传相似度的变化范围是0.5902～0.9016，遗传距离的变化范围是0.0984～0.4098；聚类分析表明种群间相似系数介于0.63～0.89，平均值为0.76。该聚类结果显示，各地理种群之间的遗传关系远近与地理距离暂无明显相关性。据此推测该病害在我国的传播扩散是以人为传播方式进行的，为大豆孢囊线虫病的可持续控制提供理论依据。该项目的完成将为植物线虫的遗传多样性及遗传结构分析建立技术平台，为探索植物寄生线虫不同地理种群的遗传变异提供技术支持，为明确大豆孢囊线虫的传播与扩散机制提供理论依据，为制定大豆孢囊线虫病的综合防治策略、促进中国大豆产业的发展奠定基础。