Characterisation of the Pathogenic <i>Colletotrichum gloeosporioides</i> Causing Anthracnose of <i>Tetrastigma hemsleyanum</i>

ABSTRACT Tetrastigma hemsleyanum , a herbaceous vine native to China, possesses significant therapeutic potential. However, its cultivation is increasingly threatened by anthracnose, a fungal disease that leads to substantial plant mortality. Therefore, evaluating the resistance of T. hemsleyanum to anthracnose is of critical importance. In this study, two members of the Colletotrichum gloeosporioides species complex— C. gloeosporioides and C . asianum— were identified from T. hemsleyanum using multilocus sequences analysis and phylogenetic analysis. C. gloeosporioides was subsequently selected for plant resistance evaluation. Through systematic screening, eight highly resistant (HR) accessions and one highly susceptible (HS) accession of T. hemsleyanum were identified. The results demonstrated that antioxidant enzyme activities in the leaves of the HR accession increased significantly more than those in the HS accession within 24 h post‐inoculation (hpi). Moreover, key genes involved in flavonoid biosynthesis and resistance mechanisms were significantly up‐regulated in the HR accession 72 hpi. These findings lay a foundational basis for further research into resistance genes and the development of disease‐resistant T. hemsleyanum cultivars.