Morpho-phylogenetic evidence reveals two new species and two new host records of Diaporthe (Diaporthales, Diaporthaceae) from Phellodendron chinense in Sichuan, China

Diaporthe species are globally distributed with a wide variety of plant hosts inhabiting diverse ecological niches and functioning as endophytes, saprobes and pathogens. Numerous species in this genus are significant pathogens responsible for a wide range of diseases in both agricultural and forest plants. In this study, eight Diaporthe strains were isolated from branches of Phellodendron chinense collected in Sichuan Province, China. Using multi-locus phylogenetic analysis of five gene regions (ITS, tef 1-α, tub 2, cal and his 3), along with morphological characterisation, two novel species — D. phellodendri and D. leshanensis — are introduced in the present study and two new host associations were recorded for D. eucommiigena and D. litseae . This study contributes to the growing understanding of Diaporthe diversity and host associations in China.