Ajuga multiflora (Labiatae) is an ornamental plant widely growing in gardens in southern China. Blackleg symptoms were observed on A. multiflora in autumn of 2005 in Hangzhou, Zhejiang Province. It was caused by Phoma species. The disease was found throughout the year, and most severe during the flowering phase. Brown water-soaked spots initially appeared on the base of leaf petioles, the lesions rapidly became black-rot, then followed by wilting and drying of individual leaves. At last the disease resulted in plant death. The typical symptom of the disease was black stem rot. The six isolates of the causal agent were all identified as Phoma multirostrata based on their morphological characteristics, pathogenicity tests and rDNA ITS sequence analyses. It is the first report ofP. multirostrata causing blackleg of A. multiflora in China.%多花筋骨草是一种在江南广泛栽培的园艺植物,2005年秋,在杭州西湖风景区发现其黑胫病.该病害一年四季均可发生,发病最严重的是花期.黑胫病首先在寄主下部叶片的叶柄处发病,病斑初期为褐色、水渍状,很快变黑,最后整株枯萎死亡,典型症状是胫基部变黑腐烂.通过对病原菌形态学观察与核糖体DNA ITS序列分析,侵染多花筋骨草的6个分离菌株均被鉴定为多喙茎点霉Phoma multirostrata.致病性试验表明,多花筋骨草是多喙茎点霉的寄主.
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