香竹箐栽培型古茶树内生真菌对植物病原真菌的拮抗活性

The Phytopathogenic Antagonistic Activity of Endophytic Fungi from Xiangzhuqing Ancient Cultivated Tea

【目的】了解香竹箐栽培古茶树内生真菌对植物病原真菌的拮抗活性。【方法】采用尖端菌丝纯化法分离内生真菌,并结合形态学和分子生物学方法对内生真菌进行鉴定,采用五点对峙培养法筛选对供试病原真菌具有拮抗活性的内生真菌菌株,对具有较强活性的菌株进行分类地位归属。【结果】从香竹箐栽培古茶树枝叶中共分离纯化出308株内生真菌,归属于61个形态型。病原真菌拮抗试验结果显示:有18株内生真菌对4种以上供试菌的抑制率大于50%,分别隶属于2门3纲10目13科14属。有13株对至少1种供试菌的抑制率大于75%,有9株对5种供试菌的抑制率均大于50%。其中,菌株Ct-BC40、Ct-BC72和Ct-LP113对5种供试菌的抑制率达80%以上,属强拮抗菌株。【结论】香竹箐栽培古茶树内生真菌中广泛分布着抑菌活性菌株,占分离菌株总数的96%以上,且抗菌活性、种属分布具有多样性。

[Purpose]In this study,the antagonistic activity of the endophytic fungi from Xiangzhuqing ancient cultivated tea against phytopathogenic fungi was investigated.[Method]Endophytic fungi were isolated by mycelium cusp purification,and identified by morphological and molecular biological methods.The active isolates were screened by five-point confrontation culture method and clarify their taxonomic status.[Result]308 of endophytic fungi were isolated from the branches and leaves of the title plant,which belonged to 61 morphological types.The results showed that the inhibition rates of 18 active endophytic fungi belonging to 2 phylum,3 classes,10 orders,13 families and 14 genera were above 50%against more than 4 species of tested pathogenic fungi.The inhibition rates of 13 isolates against at least one species of tested pathogenic fungi were more than 75%,and those of 9 isolates against 5 species of tested pathogenic fungi were over 50%.Of which,there are three strains Ct-BC40,Ct-BC72 and Ct-LP113 that had an inhibitory rate of more than 80%on 5 species of tested pathogenic fungi,respectively.[Conclusion]Active endophytic fungi accounting for more than 96%of the total isolates were widely distributed in Xiangzhuqing ancient cultivated tea,and their antifungal activities and species distribution are diverse.