因系，进行分子标记定位，以便应用于育种实践。【方法】以感病籼稻品种JG30 为轮回亲本，Y238 为供体进行杂交、回交、自交培育近等基因系；以JG30/Y238 的一个BC6F2 代群体为定位群体，利用分离集团分析法（BSA），借助SSR、EST、STS等分子标记对Xa30(t)进行分子标记定位。【结果】成功培育了携有Xa30(t)基因的水稻抗白叶枯病近等基因系CBB30。从343个分子标记中筛选出4个能揭示抗感多态性的标记RM1341、V88、C189 及03STS，用该4个标记对BC6F2代群体303个单株进行分子检测和连锁分析，结果表明上述4个标记均位于水稻第11染色体长臂，与Xa30(t)的遗传距离分别为11.4cM、11.4cM、4.4cM及2.0cM，且它们位于Xa30(t)基因的同一侧。【结论】通过构建近等基因系及分子标记检测找到4个与Xa30(t)基因连锁的标记RM1341、V88、C189 及03STS，
【Objective】A new rice bacterial blight resistance germplasm (Y238) was identified from the wild rice species Oryza rufipogon and the resistance locus was transferred to the cultivated rice to breed near-isogenic line. Molecular mapping of the resistance gene was carried out to put it into practical use in the future. 【Method】The resistance gene Xa30(t) in Y238 has been introduced into JG30 by cross, backcrosses and selfing. A BC6F2 population was used for molecular mapping of Xa30(t), and Bulked Segregant Analysis (BSA) was adopted to survey SSR, EST and STS molecular markers. 【Result】Four markers, RM1341, V88, C189 and 03STS displayed polymorphism between the susceptible-pool and resistant-pool. By analyzing the 303 individuals of the BC6F2 population with the mentioned four markers together with their resistance phenotypes, the gene Xa30(t) was mapped on the long arm of rice chromosome 11. Linkage analysis revealed that RM1341, V88, C189 and 03STS located on the same side of Xa30(t), with genetic distances of 11.4 cM, 11.4 cM , 4.4 cM and 2.0 cM respectively. 【Conclusion】The near-isogenic line CBB30 harboring a new rice bacterial blight resistance gene Xa30(t) was developed. Four molecular markers RM1341, V88, C189 and 03STS that link gene Xa30(t) were detected, and Xa30(t) was mapped on the long arm of chromosome 11.