Characterization of <i>Pestalotiopsis chamaeropis</i> causing gray blight disease on tea leaves (<i>Camellia sinensis</i>) in Chongqing, China
Yingjuan Chen, Yuhe Wan, Liang Zeng, Qing Meng, Lianyu Yuan, Huarong Tong
Abstract
Gray blight, caused by Pestalotiopsis-like species, is one of the most serious diseases in tea [Camellia sinensis (L.) O. Kuntze] production. In this study, eight Pestalotiopsis isolates obtained from diseased tea leaves collected in Chongqing, China were identified as P. chamaeropis Maharachch, K.D. Hyde & Crous. Pestalotiopsis chamaeropis as a causal agent of tea gray blight disease was clearly distinguished from other species in the genus Pestalotiopsis by morphological characteristics and phylogenetic analysis based on a combination of the internal transcribed spacer (ITS), beta-tubulin (β-tubulin), and partial translation elongation factor 1-alpha (TEF) genes. Pathogenicity was confirmed by inoculation of a conidial suspension of P. chamaeropis on wounded tea leaves. Difenoconazole, a highly active and low toxicity fungicide, demonstrated significant antifungal effect towards P. chamaeropis, with an EC50 of 0.470 µg/mL.