This paper aims to study the pathogen isolation and identification of a kind of disease causing browning on tea buds. The pathogenic strain was obtained according to Koch's Rule. The results of morphological observation of strains and the rDNA ITS molecular identification under the condition of PDA culture showed that the pathogen was a fungus of phoma. The pathogenic strain was further identified in according to the identification procedures of phoma. After 7 days on the OA and MA culture medium, the average diameter of colonies was 6.0-6.4 cm. Pycnidia were globose with 1-2 ostioles, glabrous or with some hyphal outgrowths. Conidia were ellipsoidal, aseptate, usually with two polar guttules, mostly (4.9-6.3) μm×(2.1-2.8) μm in size. The NaOH reaction was positive on OA and MA, the colour became yellow-green. The characteristics described above showed that the pathogen was preliminarily identified as Phoma adianticola. This disease of tea buds caused by P. adianticola may be a new disease of tea plant. According to the symptoms of infection, this disease was temporarily described as the buds-browning disease of tea.%对一种引起茶树芽头褐变的病原进行了分离鉴定研究。通过柯赫氏法则，成功分离得到了致病菌株。菌株 PDA 培养条件下的形态学和 rDNA-ITS 分子鉴定结果表明，此病原菌为茎点霉属真菌。按照茎点霉属真菌鉴定程序开展了鉴定研究。此菌在 OA 和 MA 培养基上培养7 d 后，菌落平均直径6.0~6.4 cm；分生孢子器圆球形，具孔口，器外壁光滑或有菌丝附着；分生孢子橄榄球形，无隔，多数具2个游球，大小为4.9~6.3μm×2.1~2.8μm；NaOH 颜色反应呈黄绿色。根据上述特征，初步鉴定此病原菌为 Phoma adianticola。由 P. adianticola 引起的茶树芽头褐变可能是茶树的一种新病害。根据此菌侵染后的症状，暂将其表述为茶树褐芽病。
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