First report of <i>Alternaria alternata</i> causing flower blight on <i>Camellia sinensis</i> in Hefei, China

Abstract

Flowers are an essential organ for sexual reproduction of higher plants. Severe lesions along with flower blight on tea (<italic>Camellia sinensis</italic>) plants were observed in the experimental tea plantation located in Hefei (China). The pathogens isolated from diseased flowers matched the morphological peculiarity of <italic>Alternaria alternata</italic>. The species characteristics of <italic>A. alternata</italic> were further confirmed by both pathogenicity tests and multi-gene phylogenetic analyses by using internal transcribed spacer (ITS), glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and beta-tubulin (TUB). The combined phylogeny analysis using sequences derived from the ITS, GAPDH and TUB showed that the isolated pathogens belong to the genus <italic>Alternaria</italic>. Pathogenicity tests conducted on healthy tea flowers and leaves manifested typical symptoms of flower blight while weaker symptoms of leaf spot, demonstrating the<italic> A. alternata</italic> isolates were the causal agents of flower blight disease on tea plants. This fungus is first reported as a pathogen causing flower blight on <italic>C. sinensis</italic> in this study.