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

<i>Diaporthe</i> 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 <i>Diaporthe</i> strains were isolated from branches of <i>Phellodendron chinense</i> collected in Sichuan Province, China. Using multi-locus phylogenetic analysis of five gene regions (ITS, <i>tef</i>1-α, <i>tub</i>2, <i>cal</i> and <i>his</i>3), along with morphological characterisation, two novel species - <i>D. phellodendri</i> and <i>D. leshanensis</i> - are introduced in the present study and two new host associations were recorded for <i>D. eucommiigena</i> and <i>D. litseae</i>. This study contributes to the growing understanding of <i>Diaporthe</i> diversity and host associations in China.