目的 深入研究川麦冬内生真菌分布的多样性和特异性,并考察其抑菌活性。方法 分别对野生川麦冬和大田栽培川麦冬的根部和叶部利用组织块法分别进行分离纯化,利用形态学和ITS序列聚类分析等分子生物学方法对所得内生真菌进行鉴定,利用菌饼法对其抑菌活性进行初步研究。结果 从川麦冬中共分离得到27株内生真菌,其中野生麦冬内生真菌(22株)明显较大田栽培麦冬内生真菌(5株)丰富,根部内生真菌(17株)明显较叶部内生真菌(10株)丰富。此外镰刀菌属和曲霉菌属为麦冬优势菌属,且镰刀菌属有根部专一定植特性,曲霉菌属却广泛分布于根部和叶部。同时,40%的麦冬内生真菌对白色念珠菌具有抑制活性,对金黄色葡萄球菌、大肠埃希菌、铜绿假单胞菌和粪肠球菌抑制菌株较少。结论 川麦冬具有丰富的内生真菌多样性,并且其内生真菌分布具有明显的环境和部位特异性。所分离的内生真菌具有一定的抑菌活性,其中H5、031p和H8 3株菌表现出较强抑菌活性,值得进一步研究。

Objective To explore the resource diversity and specificity of fungal endophytes from the Ophiopogon japonicas and their antimicrobial activities. Methods Fungal endophytes were isolated from roots and leaves of wild and cultivated O. japonicas by tissue block method. Those fungal endophytes were identified by morphological methods and phylogenetic analysis of ITS sequences. And the antimicrobial activities of those fungal endophytes were estimated by agar disk containing mycelium method. Results Twenty-seven fungal endophytes strains were isolated from O. japonicas. There was more fungal endophytes diversity in wild plants (22 strains) than cultivated plants (5 strains). Likewise, there was more fungal endophytes diversity in roots of O. japonicas (17 strains) than the leaves (10 strains). And Fusarium and Aspergillus were the dominant genus in O. japonicas. The F. spp. fungal endophytes only isolated from roots while A. spp. from both roots and leaves. In addition, 40% fungal endophytes displayed potent inhibition of Moniliaalbican. Only one or two fungal endophytes strains showed obvious inhibition of Staphyloccocus aureus, Escherichia coli, Pseudomonas aeruginosa and Enterococcus faecalis. Conclusion O. japonicas is rich in fungal endophytes and those fungi distributed with relative specificity characteristics on environment and space. Those fungal endophytes display the antimicrobial activities, especially stain H5, 031p, and H8 with potent inhibition activity are worthy of further research, development, and application.

四川省科技厅科技支撑计划项目(2016NZ0058);四川省教育厅重点科研项目(16ZA0323);四川省大学生创新创业训练计划项目(201510639086)