禾本科植物内生真菌研究 5.中国产部分epichloё内生真菌的遗传多样性

Epichloё内生真菌(epichloё endophytes)是禾本科植物的共生真菌,开展其多样性研究对菌株的生物学特性和进化规律的了解以及开发利用都有着十分重要的意义。本研究筛选了12条随机引物对24株epichloё内生真菌进行RAPD扩增,探讨真菌种类、宿主种类、采集地和菌株间的遗传多样性。结果表明,宿主为拂子茅Calamagrostis sp.、雀麦Bromus sp.、披碱草Elymus sp.、小颖羊茅Festuca parvigluma Steud.的菌株分别独立聚为一个分枝;而宿主为鹅观草Roegneria spp.的Neotyphodium属菌株聚类情况较为复杂;宿主为早熟禾Poas pp.的菌株分别在三个不同的分枝,表现出丰富的遗传多样性。以上结果反应了我国具有丰富的epichloё内生真菌资源,它们和其宿主之间有着比较明显的相互关系。本研究还显示,采集于南京的拂子茅与其内生真菌共生可能发生在较久远的年代。

Grass endophyte researches 5. Genetic diversity in some Chinese epichloё endophytes

Mutualistic associations between epichloё endophytes and gramineous plants are receiving more and more attention. Investigations of the endophytes’ diversity are facilitative to understand their biologicalproperties and evolutionary relationships. Random amplified polymorphic DNA (RAPD) markers were used to investigate genetic diversity and evolutionary characteristics of 24 endophytic fungal isolates. Isolates from Calamagrostis sp., Bromus sp., Elymus sp. and Festuca parvigluma Steud. significantly clustered respectively; clusters for Neotyphodium isolates obtained from Roegeria spp. showed comparatively complicated, while isolates obtained from Poa spp. tended to be divided into three groups. It could be concluded that the genetic relationship among the epichloё endophytes native to China is quite diverse. The results also indicated the mutualistic relationship between Calamagrostis sp. collected from Nanjing and its endophyte could be traced back to ancient time.