茶树内生真菌的分离及其在寄主组织中的分布特征

Isolation of Endophytic Fungi in Teaplant(Camellia sinensis) and Their Distribution Patterns in Different Tissues

为探索植物内生真菌(Endophytic fungi)的物种多样性及其应用潜力,作者自健康茶树组织中分离内生真菌,并分析其在不同茶树组织中的分布特征。结果表明：健康茶树组织中内生真菌分布普遍,除花瓣外,茶树不同组织中均能不同程度地分离到,特别是在叶片和枝条中,内生真菌丰富,成熟叶片中的分离频率高达93．88％～100％；自994个不同茶树组织块中,共分离到553个真菌分离物；自同一茶树叶片中可分离到3种以上内生真菌,最多可分离到6种内生真菌。茶树内生真菌的分布具有明显的组织专化性。在其种类和数量上,表现为叶、枝条＞花托、种托＞种皮、根＞芽、种胚、花瓣的明显趋势；叶芽中以内生细菌的分布为主,分离频率占65％,而在成熟叶片中则以内生真菌为主,分离频率占93．88％。茶树叶片成熟过程中,内生细菌逐渐减少,而内生真菌逐渐增多,表现为较有规律的内生菌种类演替；内生真菌在茶树不同组织中的分布特征可能与茶树不同组织所含的化学物质有关。

Endophytic fungi are the common inhabitant in plants. In order to evaluate endophyte biodiversity and its potential effects on host plants, we isolated endophytic fungi in different tissues of tea （ Camellia sinensis） trees. Results showed that endophytic fungi inhabited in different tissues of tea except the petal. More fungi were isolated in leaves and shoots ; the isolation frequency was from 93.88% to 100% in old leaves. A total of 553 fungal isolates were isolated from 994 segments of different tissues of tea tree. The results also indicated that several different fungus species could be isolated from a single leaf of tea trees. So tea plant leaves harbour a complex assemblage of endophytic fungi. Some endophytic fungi were isolated more frequently from mature leaves and shoots than from leaf buds and roots, while some endophytic bacteria were distributed more frequently in leaf buds. It was suggested that host tissue - specific chemistry might influence the distribution patterns of endophytes.