中国兰属植物菌根真菌的AFLP多样性分析

对19株分离自不同地理分布和生态型的中国兰属植物菌根共生丝核菌进行了AFLP分析，12对引物组合共扩增出1 869条带，其中1 016条具有多态性，平均多态性比率达54.4%。AFLP分析结果采用UPGMA聚类，19株菌的相似系数在0.61～0.89之间；聚类关系显示兰花地理分布、所属种和生态类型是影响中国兰属植物菌根真菌多样性及其与兰花间专一性关系的关键性因素。地生型的春兰和云南的附生兰与其共生菌根真菌之间有着较严格的专一性关系。

AFLP Diversity in the Mycorrhizal Fungi of Cymbidium Plants

Amplified fragment length polymorphism (AFLP) was used to study diversity of 19 representative mycorrhizal Rhizoctonia strains, which isolated from 7 species Chinese orchids (Cymbidium) distributed in different sites and belonged to different ecologic types. A high degree of diversity was found among the mycorrhizal Rhizoctonia strains. 1 869 bands were got by using 12 pairs of AFLP primers, and among them 1 016 bands were polymorphism, the mean percentage of polymorphism was 54.4%, which indicated that AFLP was a greatly efficient method to study the diversity of mycorrhizae of Chinese orchids (Cymbidium). The AFLP results were analyzed for similarity among strains via unweighted pair-group means cluster analysis, Similarity among 19 mycorrhizal Rhizoctonia strains ranged from 0.61 to 0.89. Cluster analysis among the mycorrhizal strains showed 3 crucial factors, the distributed environments，orchids species and ecologic type of orchids, which affected the diversity of Chinese orchids (Cymbidium) symbiotic mycorrhizae and the speciality-relation between mycorrhizae and hosts. And the terrestrial orchids belong to Cymbidium goeringii and epibiosis orchids of Yunan province showed strongly strict speciality-relation with the stains isolated from them.