First Report of <i>Alternaria alternata</i> Causing Branch Blight on <i>Platycladus orientalis</i> in China

ABSTRACT Platycladus orientalis is widely distributed in China and is an excellent afforestation tree with uses for timber, medicinal, ornamental and landscape purposes. Branch blight was observed on cypress plants in Zhejiang Province of China. Three fungal isolates (CSAL1, CSAL2 and CSAL3) were obtained by tissue isolation from diseased samples. The isolates were identified as Alternaria alternata based on morphological characteristics and a multi‐gene phylogenetic tree constructed by combining sequences of the internal transcribed spacer (ITS), large subunit ribosomal RNA (LSU), glyceraldehyde‐3‐phosphate dehydrogenase ( gapdh ), translation elongation factor 1‐alpha ( tef 1 ) and Alternaria alternata major allergen ( Alt a 1 ). The pathogenicity of the isolates was confirmed by fulfilling Koch's postulates. To the best of our knowledge, this is the first report of A. alternata causing branch blight on P. orientalis in China.