Morpho-molecular approach reveals three novel endophytic fungi in Polyschema (Pleosporales, Latoruaceae) associated with roots of baobab trees in Yunnan, China.

Abstract

Endophytic fungi associated with roots of the baobab tree (Adansonia digitata L.) remain poorly documented in terms of species diversity worldwide. During an ongoing fungal survey in the dry-hot valleys of Honghe (Yunnan Province, China), five endophytic fungal strains were isolated from healthy roots of A. digitata. Based on multi-locus phylogenetic analyses of four loci (ITS, LSU, SSU, and rpb2), combined with morphological observations, all five strains were identified as belonging to the genus Polyschema. Hence, three novel species are introduced in the present study, namely P. adansoniae-digitatae, P. hongheense, and P. radicicola. This study constitutes the first record of Polyschema from mainland China. Detailed morphological descriptions, illustrations, and phylogenetic placements of the three new species are provided. Additionally, the species diversity, morphology, and phylogeny of Polyschema are updated and discussed. These findings enrich knowledge of endophytic fungal diversity associated with baobab in China and provide insights into the taxonomy and diversity of Polyschema. Furthermore, an updated discussion on the ecology and genera within the family Latoruaceae is presented.