Abstract: A bacterium was isolated from rice seeds in Jiaxing of Zhejiang Province, China. It has been confirmed as Acidovorax avenae subsp. avenae by bacteriological tests, differential media, pathogenicity test, Biologand fatty acid methyl ester(FAME) analysis(computer aided numeric taxonomic methods). It revealed that A. avenae subsp. avenae is different from the bacterium recorded in Zhejiang in 1960s although they produced similar symptom, bacterial stripe, on rice seedlings. A. avenae subsp. avenae could be isolated from discolored seeds aswell as from healthy looking seeds of rice. They significantly affected seed germination and seed vigor when 10¹⁰cfu/mL and 10⁸ cfu/mL of the bacterium were inoculated on rice seeds. The bacterium could transmitted from seeds to seedlings with 0.2%-5.0% of infection. This suggested that rice seed is very infectant infection source fort ransmission of bacterial stripe and care must be taken for introduction of seeds.

Key words: Acidovorax avenae subsp. avenae, bacteriology, characterization, pathogenicity, seedborne bacteria

摘要： 从中国浙江省嘉兴市的稻种上分离出一种细菌，经细菌学、 鉴别培养基、致病性、Biolog及脂肪酸分析测定，表明该细菌属于Acidovorax avenae subsp. avenae。 该细菌在水稻苗期产生褐色条斑，与浙江省60年代报道的细菌性褐条病相似，但在细菌学特征上完全不同。A. avenae subsp. avenae既可从褐变稻谷上，也可从健康种子上分离到。用10⁸和10¹⁰个/mL细菌接种稻谷， 种子的发芽及活力明显受到影响。此细菌的种传发病率为0.2%～5.0%，表明种子是传播此种细菌病害的重要侵染源。

关键词: 特征化, Acidovorax avenae subsp. avenae, 种传细菌, 细菌学, 致病性