烤烟苗期茎部腐烂病病原菌九州镰孢菌的生物学特性

作者于2012年在烤烟（Nicotiana tabacum L.）苗期发现茎部腐烂病。经病原菌的形态特征观察、rDNA-ITS和EF-1α序列分析，该致病菌被鉴定为九州镰孢菌（Fusarium kyushuense）。该病原菌在利马豆培养基上生长温度范围为5~ 41℃，最适30℃；分生孢子产生温度范围为10 ~ 35℃，最适35℃；分生孢子萌发温度范围为5~42℃，最适30~35℃；分生孢子萌发相对湿度范围为70~100%，最适100%；可生长pH值为2~11，最适5~7；光照对菌丝生长和分生孢子萌发没有影响，光暗交替培养菌丝生长变慢，但分生孢子产量增加；在供试的95种碳源中，该病原菌能利用葡萄糖、麦芽糖、反丁烯二酸等89种碳源，不能利用N-乙酰基D-半乳糖胺、N-乙酰基-?-D-葡萄糖胺、葡萄醛酰胺、癸二酸、L-丝氨酸和腺苷-5’-磷酸盐6种碳源。 

Biological characteristics of Fusarium kyushuense causing tobacco seedling stem rot

The stem rot of flue-cured tobacco (Nicotiana tabacum L.) was observed in tobacco seedlings in 2012. Its pathogen was identified as Fusarium kyushuense according to its morphology, pathogenicity and rDNA ITS and EF-1α gene analysis. The temperature for the pathogen to grow on LBA ranged from 5℃ to 42℃ with the optimum temperature 30℃, for sporulation ranged from 10℃ to 35℃ with optimum temperature 35℃; for conidial germination ranged from 5℃ to 42℃ with optimum 30℃ to 35℃. The suitable relative humidity for conidial germination of the pathogen ranged from 70% to 100% with optimum 100%. The pathogen could grow under pH 2-11 with the optimum pH 5-7. Light had no effect on mycelial growth and conidial germination. Light and dark alternation slowered the mycelial growth, but it enhanced sporulation. Among the 95 carbon resources in Biolog FF Microplate, 89 ones could be utilized by F. kyushuense. The carbon resources which could not be used by the pathogen include N-acetyl-D-galactosamine, N-acetyl-?-D-glucosamine, glucuronamide, sebacic acid, L-serine and adenosine-5’-monophosphate.