黑龙江省水稻立枯病病原鉴定及致病性研究

Studies on Identification of Pathogen and Pathogenicity of Rice Seedling Blight in Heilongjiang Province

对分离自黑龙江省16个市县的369个水稻立枯病菌株进行了形态学和分子生物学鉴定,它们分别属于3个属9个种。致病性测定结果表明,尖孢镰刀菌(Fusarium oxysporum)和轮枝镰刀菌(Fusarium verticillioides)的致病性相对较强,立枯丝核菌(Rhizoctonia solani)其次;腐皮镰刀菌(Fusarium solani)、木贼镰刀菌(Fusarium equiseti)、燕麦镰刀菌(Fusarium avenaceum)、层出镰刀菌(Fusarium proliferatum)和腐霉菌(Pythium spp.)的致病性相对较弱;Fusarium commune不具致病性,说明其只是一种腐生菌,不引起水稻的立枯病。结合分离出现频率和致病性测定结果,确定尖孢镰刀菌(F.oxysporum)和轮枝镰刀菌(F.verticillioides)为黑龙江省水稻立枯病的优势病原菌。

369 strains were isolated from the samples of rice seedling blight in 16 counties of HeilongjiangProvince, which were divided into three genera and nine species through morphological observation and moleculardetection. The results of pathogenicity test indicated that Fusarium oxysporum and Fusarium verticillioides showedstronger pathogenicity than others. The virulence of Rhizoctonia solani is weaker than F. oxysporum and F. Verticillioides, but stronger than that of Fusarium solani, Fusarium equiseti, Fusarium avenaceum, Fusarium proliferatum and Pythium spp. Fusarium commune has no pathogenicity to rice seedling, suggesting that it＇s just a kind of saprophytic pathogen. According to the occurrence frequency and the results of pathogenicity test, F. oxysporum and F. verticillioides were considered as the dominant pathogens of rice seedling blight in Heilongjiang Province.