Non-mycorrhizal fungal endophytes in two orchids of Kaiga forest (Western Ghats), India

We used standard isolation protocols to explore the endophytic fungal communities in three tissue types of two dominant orchids (Bulbophyllum neilgherrense and Vanda testacea) of the Kaiga forest of the Western Ghats. We surface sterilized and assessed 90 segments of each orchid for the occurrence and diversity of endophytic fungal taxa. The 118 fungal isolates were obtained from root, bulb and leaves of B. neilgherrense, consisting of 17 anamorphic taxa (range, 10?C15 taxa) with 1.3 fungal taxa per segment (range, 1.2?C1.4 taxa). Four taxa (Aspergillus flavus, A. niger, Penicillium sp. and morpho sp. 1) belonged to the core group (11.1%?C32.2%). The relative abundance of A. flavus and morpho sp. 1 was more than 10%. A total of 130 fungal isolates from roots, stems and leaves of V. testacea yielded 20 anamorphic taxa (range, 11?C15 taxa) with 1.4 fungal taxa per segment (range, 1.4?C1.5 taxa). Aspergillus flavus, A. niger, A. ochraceus, Gliocladium viride, Penicillium sp. and morpho sp. 1 belonged to the core group. Relative abundance exceeded 10% for A. flavus, A. niger, and morpho sp. 1. The Simpson and Shannon diversity indices were higher in leaf than root or bulb/stem of both orchids. Jaccard??s similarity coefficient was higher between root and leaf in both orchids (56.3%-60%) than between other pairs. Our study revealed that the endophytic fungal assemblage and diversity of B. neilgherrense and V. testacea of Kaiga forest of the Western Ghats were relatively similar between orchids and their tissues.