Phaeotubakia lithocarpicola gen. et sp. nov. (Tubakiaceae, Diaporthales) from leaf spots in China

Abstract

Tubakiaceae represents a distinct lineage of Diaporthales, including its type genus Tubakia and nine additional known genera. Tubakiaceous species are commonly known as endophytes in leaves and twigs of many tree species, but can also be plant pathogens causing conspicuous leaf symptoms. In the present study, isolates were obtained from diseased leaves of Lithocarpus glaber collected in Guangdong Province, China. The identification was conducted based on morphology and phylogeny of combined loci of 28S nrRNA gene (LSU), internal transcribed spacer regions and intervening 5.8S nrRNA gene (ITS) of the nrDNA operon, translation elongation factor 1-alpha (tef1) and beta tubulin (tub2). As a result, a distinct clade in Tubakiaceae was revealed named Phaeotubakia lithocarpicola gen. et sp. nov., which was distinguished from the other tubakiaceous taxa by its dark brown conidiogenous cells and conidia.