【作者】 刘晓辉； 成国英； 林兴华；

【Author】 LIU Xiaohui, CHENG Guoying, LIN Xinghua (The College of Plant Science in Huazhong Agricultural University, Wuhan 430070)

【机构】 华中农业大学植科院；

【摘要】 用IR24、IRBB4(Xa4)、IRBB5(Xa5)、IRBB7(Xa7)、IRBB11(Xa11)、IRBB13(Xa13)、XM5(Xa19)、M41(Xa15)、IRBB21(Xa21)、丰锦(Xa18))等十个近等基因系水稻品种作鉴别寄主,对来自同一田块的白叶枯病菌、原中国稻白叶枯病菌Ⅲ、Ⅳ、Ⅵ、Ⅶ型模式菌株及其单细胞菌系的毒力进行了测试,结果显示,同一病田不同的分离菌株之间、各模式菌株与其单细胞菌系之间、以及同一母株的不同单细胞菌系之间,都存在致病差异性;这表明:田间病菌的自然群体,是由不同毒力的单细胞菌系组成的复合体,采用“断叶沙培,切口取胶”或划线分离法,得到的一定是含不同毒力细胞的复合菌体。为避免不同毒力细胞菌系的相互干扰,探讨小种分子鉴定系统时,应采用不同毒力的单细胞菌系作为试材。更多还原

【Abstract】 It was compared on the differential hosts of the Near Isogenic Lines consisting of 10 rice varieties [IR24, IRBB4 (Xa4)、IRBB5 (Xa5), IRBB7 (Xa7)、IRBB11 (Xa11)、IRBB13 (Xa13)、XM5 (Xa19)、M41 (Xa15)、IRBB21 (Xa21)、Fengjin (Xa18)] that the virulence of strains Xanthomonas oryzae pv. oryza (XOO) isolated from a same rice field (SRF) and XOO model strains of China Bacterial Blight of Rice representing the pathotypes Ⅲ、Ⅳ、Ⅵ、Ⅶ and their mono-cell-clones (MCCs). The result indicated there were remarkable differences among the virulence of the strains isolated from SRF, even from a same diseased leaf. So were the model strains and their MCCs and even among the MCCs isolated from a model strain. It suggested that the field population of XOO should be made up of different virulent cells. It must be a mixture with variant cells that the strains isolated by picking up a bacterial ooze from the top of cutting lines of diseased leaf sections plunged in sands with water or isolated by streak culture. In order to avoid the interference among different virulent cells, mono-cell clones with different virulence should be used as test materials when probing into the molecular identifying system of pathogenic races.更多还原