内生真菌在真菌学基础理论和活性物质开发利用方面具有重要研究价值。关于被子植物、裸子植物、苔藓、地衣等植物类群内生真菌的研究已经取得丰硕成果，但是目前关于蕨类植物内生真菌的研究还鲜有报道。桫椤属是现今仅存的木本蕨类植物，是孑遗植物中蕨类的代表，全部种类已经列入国际濒危物种保护名录。本项目以桫椤属植物作为研究对象，采用经典真菌分类方法并结合SSCP技术、DNA序列分析技术和DGGE、克隆文库等分子生物学技术，对我国桫椤属植物内生真菌分类学、多样性、系统学、生态分布规律等进行研究，旨在弄清桫椤属植物内生真菌的多样性，发现真菌新种或新记录种，并为生物活性物质的开发利用收集大量内生真菌资源；从机制上阐明地理环境、宿主种类、组织性质等因素对桫椤属植物内生真菌群落组成与分布的影响；探讨潜在致病菌在桫椤属植物组织中的分布特征，为病害预报、预防与防治提供理论基础，提升我国濒危的桫椤属植物保护水平。

Endophytic fungi were highly valuable for the basic theory of Mycology and the development of active material. The predecessor has procured plentiful and substantial progeny, but they basically circumfuse the endophytic fungi of the plant groups, such as gymnosperm, angiosperm and lichen, etc.. At present, endophytic fungi from ferns were rarely studied both in China and abroad. Alsophila were the only existing woody ferns and were representative ferns. All the Alsophila had been included in international protection list of endangered species. In order to clarify the influence of such factors as geographical environment, host species and organization nature on community composition and distribution of endophytic fungi from Alsophila, endophytic fungi from Alsophila were studied using both classic fungi classification method and molecular biology technology such as SSCP, DNA sequence analysis technology, DGGE, cloning library etc.. At the same time this study was to make clear the diversity of endophytic fungi, find out new species or new records, collect a lot of endophytic fungi resources for the development and utilization of biological active substance, discuss the distribution characteristics of potential pathogenic fungi and was to expect to provide the theory basis for prediction and control of diseases.