安徽茶园昆虫病原真菌种群结构,生态位分化及其维持机制研究

Anhui is major tea producing area in China, but the pests limit the tea output and quality. Utilization of natural enemies to control pests is the important means of ecological prevention and cure. Based on existing research, the entomopathogenic fungi was rich in tea plantations. As we know the fungal population diversity、niche differentiation and the maintaning mechanism in tea garden ecosystem which is a vital significance for pest management、biological conservation and exploitation of insect pathogenic fungi. In this study, the entomopathogenic fungal specimens from two main tea plantations Babie Mountains and Yellow Mountains are used for object.The classical classification technology、sequencing gene fragments、 PCR-DGGE and the principles of niche breadth and niche overlap are utilized to analyze the population diversity、 genetic heterogeneity and niche structure in tea plantation environments. Through above studies, the relevant ecological theories of species coexistence such as niche differentiation and population diversity will be tested in tea garden systems.In preliminary research, we found the niche width of Beauveria bassiana was biggest, but the niche overlap with other entomopathogenic fungi was small in pure pine forest in which has less species. This study would be the basis of using Beauveris bassiana to control pests in pure pine forests.

安徽是我国重要的产茶区，而茶树害虫是影响茶叶产量和品质的主要因子，利用天敌控制害虫是实现绿色防控的重要手段。已有研究发现茶园分布着丰富的昆虫病原真菌，了解该生态系中这类真菌的种群多样性、生态位分化及维持其稳定的机制，对于茶园害虫治理及生物资源保护，以及昆虫病原真菌资源的开发利用，都具有重要意义。本研究拟在安徽两大主要茶区大别山和黄山选择粗放管理的茶园为研究样地，全年调查采集昆虫病原真菌标本。利用经典分类技术、基因片段测序、PCR-DGGE等手段，结合生态位宽度和生态位重叠度等生态指标，分析茶园中昆虫病原真菌的种群多样性、遗传异质性及生态位结构，从分子生物学水平和生态学水平上揭示昆虫病原菌种群多样性及生态分化的维持机制。项目组在前期研究中发现，在马尾松纯林中昆虫病原真菌种类较单一，优势种球孢白僵菌具有较高的遗传异质性，且生态位宽度最大，生态位重叠较小，为马尾松林生物防治提供了理论和实验依据。

安徽是我国重要的产茶区，而茶树害虫是影响茶叶产量和品质的主要因子，利用天敌控制害虫是实现绿色防控的重要手段。本课题通过调查采集大别山雾里青茶区和黄山毛峰茶区不同经营管理方式茶园的昆虫病原真菌，发现粗放经营茶园分布着丰富的昆虫病原真菌，其中以环链棒束孢、球孢白僵菌以及粉棒束孢为优势种群。结合生态位宽度和生态位重叠值等生态指标，研究了茶园昆虫病原真菌优势种群的生态位结构；利用分子生物学手段研究了昆虫病原真菌优势种群的遗传异质性。从分子生物学水平和生态学水平上揭示昆虫病原真菌在茶园中种群多样性及生态分化的维持机制。