Endolichenic fungi in lichens of Champawat district, Uttarakhand, northern India

Eleven lichen species belonging to five families (two fruticose and nine foliose) growing on the bark of Quercus leucotrichophora trees from four forests of Champawat district, Uttarakhand state, northern India were studied for their endolichenic fungal assemblage. We obtained 942 isolates of endolichenic fungi belonging to 33 morphospecies from these lichens. Xylaria spp. dominated the assemblage of 6 of the 11 lichens; it was the most common endolichenic fungus and constituted 31.4% of the total isolates. In co-culture experiments where 33 Xylaria isolates and select endolichenic fungi were cultured together, 39% of the combinations showed mutual stasis, while in 36% of the challenges, Xylaria overgrew the other endolichenic fungus co-cultured with it; Xylaria was inhibited only in 6% of the challenges. Of the 62 isolates tested by bioautogram, 45 and 37 isolates exhibited antialgal and antifungal activity, respectively, while 30 isolates showed both antialgal and antifungal activities. While production of such metabolites by the endolichenic fungi could aid them in overcoming competition within the lichen thallus, it is possible that they also alter the ecological fitness of lichens.