黑龙江水稻胡麻叶斑病病原菌的分离鉴定及生物学特性

Pathogen isolation and identification of rice brown spot and its biological characteristics in Heilongjiang

对水稻胡麻叶斑病病原菌进行了分离和形态学观察结果表明,其分生孢子呈褐色,直立或弯曲,脐部稍突出,表面光滑,纺锤形或圆柱形,有5～10个假隔膜;分生孢子梗褐色,弯曲,部分有分枝。分子鉴定得出病原菌ITS区序列与稻平脐蠕孢有性态(Cochliobolus miyabeanus)序列相似程度达到99%。确定该病原菌为稻平脐蠕孢(Bipolaris oryzae)。其生物学特性研究结果表明,水稻胡麻叶斑病病原菌生长最适条件为光暗交替、酸碱度中性、25℃、碳氮源为可溶性淀粉和甘氨酸。

Pathogen of rice brown spot was isolate d by conventional fungi. The results of observation showed that the conidia were brown, erect or curved, the umbilical cord was slightly protruding, the surface was smooth, spindle-shaped or cylindrical, and there were 5-10 pseudomembrances. Molecular identification showed that sequence of ITS region of pathogenic fungus was similar to that of sexual(Cochliobolus miyabeanus) sequence of vermicularis oryzae. The pathogen was identified as Bipolaris oryzae and the biological characteristics were studied as well. The optimum conditions for pathogen growth were light and dark alternation, neutral pH and 25 ℃, and carbon and nitrogen sources were soluble starch and glycine.