The identification of the pathogen causing flue-cured tobacco corynespora leaf spot in Guangxi and its biological characteristics were preliminarily studied. The pathogen of flue-cured tobacco corynespora leaf spot was identified as C. cassiicola based on its morphology, pathogenicity and the analysis of sequences of ribosomal rD-NA-ITS. The optimum temperature, pH value, carbon source, nitrogen source and light treatment for the myceli-al growth of C. cassiicola were 27. 5 ℃ , 6, maltose, potassium nitrate and full light, respectively. For the sporu-lation, the optimum temperature was 30 °C , and the best carbon/ nitrogen source was lactose/ potassium nitrate, and full darkness was the most suitable light treatment. For conidial germination , the most favorite temperature, relative humidity and light treatment were 27. 5 ℃ , 100% and 12 h alternate light, respectively. The lethal temperature for the spores was 52 ℃. It is the first report of the tobacco disease in Guangxi, China.%本文对广西烤烟棒孢霉叶斑病的病原进行鉴定,并对其生物学特性进行初步研究.根据该病原菌的形态特征、致病性及rDNA-ITS序列测定,将引起广西烤烟棒孢霉叶斑病的病原菌鉴定为山扁豆生棒孢(Corynespora cas siicola).生物学特性测定结果表明:27.5℃、培养初始pH为6、以麦芽糖作为C源、硝酸钾作为N源及完全光照等条件最适合其菌丝生长；30℃、以乳糖作为C源、硝酸钾作为N源及完全黑暗等条件最有利于该菌分生孢子形成；27.5℃、湿度为100％+水膜、12 h光暗交替等条件最有利于分生孢子萌发；分生孢子的致死温度为52℃.这是该病在广西的首次报道.
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