First Report of <i>Botryosphaeria dothidea</i> Causing Leaf Blight on <i>Aesculus chinensis</i> in China

ABSTRACT In July 2024, a leaf blight disease was observed on Aesculus chinensis plants in Shandong Province, China. The disease presented as brown lesions progressing to light brown. The morphological features of colonies and conidia observed on PDA medium were consistent with those of Botryosphaeria dothidea . Pathogenicity tests were conducted on A. chinensis leaves using both greenhouse‐grown seedlings and field‐grown mature trees through a wound inoculation method. Brown lesions developed on the inoculated leaves of both seedlings and mature trees, whereas no symptoms appeared on the control leaves. The ITS, translation elongation factor 1‐alpha ( TEF1 ) and β‐tubulin ( TUB ) regions from the isolates were amplified and sequenced. BLAST analysis of these three genes revealed 99.61%–100.00% identity with the corresponding sequences of B. dothidea ex‐epitype strain (CBS 115476) available in GenBank. Phylogenetic analysis further confirmed the identification of the pathogen as B. dothidea . This study represents the first report of B. dothidea causing leaf blight disease on A. chinensis in China.