樟科與云香科之中草藥植物內生真菌的鑑定與抗菌特性

Identification of Endophytic Fungi of Medicinal Herbs of Lauraceae and Rutaceae with Antimicrobial Property

本研究為鑑定分離自臺灣中部與北部中草藥植物之樟科（67株）與云香科（89株）共156株的內生真菌。依形態與分子序列鑑定顯示，156株內生真菌可被分成35屬19科，以Colletotrichum、Guignardia、Hypoxylon、Nigrospora、Phomopsis及Xylaria等屬真菌被分離頻率較高，其中又以Xylariaceae中的Hypoxylon與Xylaria屬真菌被分離比率最高。此外云香科中的Citrus與Zanthoxylum屬植物和樟科中的Cinnamomum屬植物，則最易分離到內生真菌。進一步利用D1/D2與ITS rDNA序列分析Xylariaceae科內生真菌的分子親緣性，得知所分離Xylariaceae科內生真菌主要可分成Xylaria與Hypoxylon兩個分子群。測試云香科與樟科所分離內生真菌對植物病原之拮抗性，顯示Lasmenia sp. CB10菌株、Ophioceras tenuisporum CI02菌株、Xylaria cubensis LA04菌株及Cyanodermella sp. TR09菌株對抑制12種植物病原真菌、3種植物病原細菌及1種卵菌表現較佳。於溫室評估CB10菌株對降低白菜炭疽病之效果，顯示該菌株可明顯降低白菜炭疽病的發生，證明CB10菌株具有防治白菜炭疽病之潛力。

This study was conducted to determine taxonomical features and antimicrobial activities of 156 isolates of endophytic fungi collected from twigs of medicinal plants of Lauraceae (67 isolates) and Rutaceae (89 isolates) in central and northern Taiwan. The 156 isolates of fungi were classified into 35 genera in 19 families based on morphological characteristics of mycelia and asexual/sexual spores, as well as molecular phylogenetic analysis of rDNA LSU D1/D2 and ITS regions. The most common endophytes were in the taxa of Colletotrichum, Guignardia, Hypoxylon, Nigrospora, Phomopsis and Xylaria, and the most common hosts were Citrus and Zanthoxylum of Rutaceae and Cinnamomum of Lauraceae. Molecular phylogenetic analysis showed that xylariaceous isolates could be separated into Xylaria and Hypoxylon groups based on rDNA of LSU D1/D2 and ITS regions. Four isolates of endophytic fungi including Lasmenia sp. isolate CB10, Ophioceras tenuisporum isolate CI02, Xylaria cubensis isolate LA04 and Cyanodermella sp. isolate TR09 were tested for antimicrobial activities using a dual culture method and Lasmenia sp. isolate CB10 and Cyanodermella sp. isolate TR09 showed better antimicrobial activity against 12 plant pathogens including 9 fungi and 3 bacteria. Spraying Chinese cabbage (Brassica rapa) plants with culture filtrates of the endophytic fungus Lasmenia sp. isolate CB10 significantly reduced severity of anthracnose of Chinese cabbage caused by Colletotrichum higginsianum under greenhouse conditions. This study suggests that the Lasmenia sp. isolate CB10 may be of potential for management of anthracnose of Chinese cabbage.