Mycoendophytic diversity and their antimicrobial potential from two epiphytic orchids of the Western Ghats forests of India

The epiphytic plants belong to a group that harmlessly grows on other plants by utilizing the nutrition from the host plants with their unique adaptation features along with symbiotic associations with fungi or bacteria.The various biological activities exhibited by the mycoendophytes inhabiting medicinally-important epiphytic orchids serve as the primary source of novel drug leads,industrially-essential enzymes,and plant growth-promoting metabolites.In the present study,a total of 956 culturable mycoendophytes out of 1600 segments belonging to 17 genera were isolated from different tissue parts of Trias stocksii and Dendrobium herbaceum.The Xylariaceae taxa were the predominant mycoendophytes present in both plants,followed by Pestalotiopsis sp.,Colletotrichum sp.,and Fusarium sp.An estimation of the Shannon-Wiener and Simpson diversity indices showed that the bulbs of T.stocksii have the highest species diversity index and the stems of D.herbaceum the lowest.The highest species richness was observed in the leaves of T.stocksii and the lowest in the leaves of D.herbaceum.Overall,T.stocksii harbored more mycoendophytes along with the highest diversity indices compared to D.herbaceum.The antimicrobial evaluation revealed that Xylaria sp.has a higher potential of producing anti-infectives and opens a new arena for industrial exploration.