Regional Station Shillong, ICAR-National Bureau of Plant Genetic Resources, Umiam, Meghalaya, India.
Deparment of Botany, University of Delhi, Delhi, India.
J Basic Microbiol. 2020 May;60(5):415-423. doi: 10.1002/jobm.201900631. Epub 2020 Mar 1.
Endophytic fungi are known to play an important role in driving the evolution of plants by conferring adaptational advantages to their host through the production of secondary metabolites and phytohormones. In this study, we evaluated the diversity and phylogenetic relationship of endophytic fungal communities from four Dendrobium species viz., Dendrobium chrysanthum, Dendrobium heterocarpum, Dendrobium hookerianum, and Dendrobium longicornu of Meghalaya, India. A total of 51 culturable endophytic fungi were isolated from the four selected orchid species. The isolates were identified based on nuclear large subunit sequences into 33 species. Approximately 91% of the isolates showed affinity to Ascomycetes, while 9% of the isolates showed BLAST search similarity to Basidiomycetes. The most common genera were Trichoderma and Xylaria. The most prevalent genera were Fusarium, which was detected in all the four Dendrobium species followed by Diaporthe, which was present in three Dendrobium species viz., D. chrysanthum, D. hookerianum, and D. heterocarpum. The Shannon index value of endophytic fungal communities was the highest in D. chrysanthum (2.66), while D. longicornu (1) had the highest Evenness index. The present study revealed that endophytic fungi in these orchids are an amalgam of pathogenic and beneficial fungi, which have, at the least, switched their lifestyle to asymptomatic endophyte in their host. To our knowledge, this is the first such report on the diversity of endophytic fungi in the four selected Dendrobium species from Meghalaya, India.
内生真菌被认为通过产生次生代谢物和植物激素赋予宿主适应优势，从而在驱动植物进化方面发挥着重要作用。在这项研究中，我们评估了来自印度梅加拉亚邦的四种石斛属植物（Dendrobium chrysanthum、Dendrobium heterocarpum、Dendrobium hookerianum 和 Dendrobium longicornu）内生真菌群落的多样性和系统发育关系。从这四种兰花中共分离出 51 株可培养内生真菌。根据核大亚基序列，将这些分离株鉴定为 33 个种。大约 91%的分离株与子囊菌门有亲和力，而 9%的分离株与担子菌门的 BLAST 搜索相似性最高。最常见的属是 Trichoderma 和 Xylaria。最常见的属是 Fusarium，在所有四种石斛中都有发现，其次是 Diaporthe，在三种石斛中都有发现，即 D. chrysanthum、D. hookerianum 和 D. heterocarpum。内生真菌群落的 Shannon 指数值在 D. chrysanthum 中最高（2.66），而 D. longicornu（1）的 Evenness 指数最高。本研究表明，这些兰花中的内生真菌是致病真菌和有益真菌的混合物，它们至少已经将生活方式转变为宿主中的无症状内生菌。据我们所知，这是关于印度梅加拉亚邦的四种选定的石斛属植物内生真菌多样性的首次此类报告。
