Phylogeny, Morphology, Distribution, and Pathogenicity of Seven Species from Leaf-Blighted in HaiNan Island, China.

Leaf blight caused by species constrains trees in China. Calonectria leaf disease on in China was first reported in HaiNan Island in 1985. No systematic investigation of species associated with diseased in HaiNan has been performed. To understand the species diversity, distribution, and pathogenicity of these , 400 isolates were obtained from 278 diseased planted in 17 sites in five regions. All 400 isolates were identified by DNA sequences of translation elongation factor 1-alpha, β-tubulin, calmodulin, and histone H3 gene regions and on morphology. Seven species, (198 isolates), (161 isolates), (29 isolates), (6 isolates), (4 isolates), (1 isolate), and (1 isolate), were identified. This is the first report of in China. , , and belong to the species complex and accounted for 97% of all isolates. The three species overlapped in vesicle shape, macroconidia size, and macroconidia septa number. Region significantly influenced and distribution. Representative isolates of , , , and producing abundant macroconidia were used in conidial suspension inoculation on seedlings; all were highly pathogenic to the two tested genotypes. The tolerances of two genotypes were significantly different. This first systematic investigation of species associated with leaf blight in HaiNan will aid selection of disease-resistant genotypes for managing leaf blight caused by species in China.