Characterization and Pathogenicity of Pestalotiopsis-Like Species Associated With Gray Blight Disease on Camellia sinensis in Anhui Province, China

Gray blight disease, caused by Pestalotiopsis-like fungi, is one of the deadliest threats to tea (Camellia sinensis) production. However, little information is known about the traits and characteristics of this pathogen. Here, a systematic survey was performed, and a total of 20 representative isolates were obtained from the leaves of tea plants affected by gray blight in two main tea plantations located in Anhui Province, China. Further analyses showed that two isolates were identified as Neopestalotiopsis ellipsospora, three isolates were regarded as Pseudopestalotiopsis chinensis, one isolate was considered as Pseudopestalotiopsis camelliae-sinensis, and the remaining isolates belonged to Pseudopestalotiopsis spp., on the basis of morphological characteristics and multigene phylogenetic analyses of the internal transcribed spacer, beta-tubulin, and translation elongation factor 1-alpha. Pathogenicity tests indicated that there were significant differences in virulence among the Neopestalotiopsis and Pseudopestalotiopsis isolates when inoculated on the leaves of the tea plant (C. sinensis 'Shuchazao'). Furthermore, varied pathogenicity was also observed for the same isolate when inoculated on different varieties of tea plants. To our knowledge, this is the first record of Neopestalotiopsis ellipsospora and Pseudopestalotiopsis chinensis causing gray blight disease of tea plants in China.