Endophytes constitute an important component of microbial diversity, and in the present investigation, seven plant species with rich ethnobotanical uses representing six families were analyzed for the presence of endophytic fungi from their natural habitats during monsoon (May/June) and winter (November/December) seasons of 2007. Fungal endophytes were isolated from healthy plant parts such as stem, root, rhizome, and inflorescence employing standard isolation methods. One thousand five hundred and twenty-nine fungal isolates were obtained from 5200 fragments. Stem fragments harbored more endophytes (80.37%) than roots (19.22%). 31 fungal taxa comprised of coelomycetes (65%), hyphomycetes (32%), and ascomycetes (3%). Fusarium, Acremonium, Colletotrichum, Chaetomium, Myrothecium, Phomopsis, and Pestalotiopsis spp. were commonly isolated. Diversity indices differed significantly between the seasons ( ). Species richness was greater for monsoon isolations than winter. Host specificity was observed for few fungal endophytes. UPGMA cluster analysis grouped the endophytes into distinct clusters on the basis of genetic distance. This study is the first report on the diversity and host-specificity of endophytic fungal taxa were from the semi evergreen forest type in Talacauvery subcluster of Western Ghats. 1. Introduction The microbes residing in the internal parts of plant tissues called “endophytes” constitute a group of plant symbionts and are a component of microbial diversity. Endophytes offer plethora of unknown advantages to the host with immense applications in agriculture and medicine [1, 2]. Recently, challenging hypotheses related to endophyte diversity [3], their role in oxidative stress protection [4], heavy metal tolerance [5], and as components of tropical community ecology [6, 7] have emerged. A perusal of the literature over the past decades indicated many ethnomedicinal plant species with rich botanical history, sampled from unique ecological niches species are known to harbor potential endophytic microbes [8]. There has been an increasing surge of interest among the research groups for the isolation of endophytes from the tropical plant species [9, 10], owing to high plant diversity. One such region represents the Western Ghats, stretching a length of 1,600？Km from the river Tapti in the state of Gujarat to the Southern tip of Kerala, recognized as one of the 34 hot spots of biodiversity. The Western Ghats represent rich flora with enormous species diversity as well as endemic taxa and are therefore recognized as one among the hot spots of
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