Tagging and mapping of rice sheath blight resistant gene

Sheath blight (Rhizoctonia solani Kuhn) is one of the severe rice diseases worldwide. In this study, an F-2 population from a cross between '4011' and 'Xiangzaoxian19' is used to identify molecular markers linked with the resistant trait. '4011' was a transgenic rice cultivar carrying a resistant gene to sheath blight, while 'Xiangzaoxian19' is a highly susceptible one. As a result, five molecular markers, including three RFLP markers converted from RAPD and AFLP markers, and two SSR markers were identified to link with the sheath blight resistant gene. This dominant resistant gene was named as Rsb 1 and mapped on rice chromosome 5. The linkage distance between the markers (E-AT:M-CAC(120), E-AT:M-CTA(230), OPN-16(2000), RM164(320) and RM39(300)) and Rsb 1 was 1.6 cM, 9.9 cM, 1.6 cM, 15.2 cM and 1.6 cM, respectively.