The elite rice cultivar Yuejingsimiao 2 （YJ2） is characterized by a high level of grain quality and yield, and resistance against Magnaporthe oryzae. YJ2 showed 100% resistance to four fungal populations collected f...The elite rice cultivar Yuejingsimiao 2 （YJ2） is characterized by a high level of grain quality and yield, and resistance against Magnaporthe oryzae. YJ2 showed 100% resistance to four fungal populations collected from Guangdong, Sichuan, Liaoning, and Heilongjiang Provinces, which is a higher frequency than that shown by the well-known resistance （R） gene donor culti- vats such as Sanhuangzhan 2 and 28zhan. Segregation analysis for resistance with F2 and F4 populations indicated the re- sistance of YJ2 was controlled by multiple genes that are dominant or recessive. The putative R genes of YJ2 were roughly tagged by SSR markers, located on chromosomes 2, 6, 8, and 12, in a hulked-segregant analysis using genome-wide selected SSR markers with F4 lines that segregated into 3 resistant （R）： 1 susceptible （S） or 1R：3S. The recessive R gene on chromosome 8 was further mapped to an interval ~1.9 cM/152 kb in length by linkage analysis with genomic position-ready markers in the mapping population derived from an F4 line that segregated into 1R：3S. Given that no major R gene was mapped to this inter- val, the novel R gene was designated as pi55（t）. Out of 26 candidate genes predicted in the region based on the reference genomic sequence of the cultivar Nipponbare, two genes that encode a leucine-rich repeat-containing protein and heavy-metalassociated domain-containing protein, respectively, were suggested as the most likely candidates for pi55（t）.展开更多
基金supported by the National Natural Science Foundation of China (Grant No. U1131003)the National Transgenic Research Projects(Grant Nos. 2009ZX08009-023 and 2011ZX08001-002)+1 种基金the Guangdong Provincial Natural Science Foundation (Grant No. 10151064001000008)the President Science Foundation of Guangdong Academy of Agricultural Sciences (Grant No. 201101)
文摘The elite rice cultivar Yuejingsimiao 2 （YJ2） is characterized by a high level of grain quality and yield, and resistance against Magnaporthe oryzae. YJ2 showed 100% resistance to four fungal populations collected from Guangdong, Sichuan, Liaoning, and Heilongjiang Provinces, which is a higher frequency than that shown by the well-known resistance （R） gene donor culti- vats such as Sanhuangzhan 2 and 28zhan. Segregation analysis for resistance with F2 and F4 populations indicated the re- sistance of YJ2 was controlled by multiple genes that are dominant or recessive. The putative R genes of YJ2 were roughly tagged by SSR markers, located on chromosomes 2, 6, 8, and 12, in a hulked-segregant analysis using genome-wide selected SSR markers with F4 lines that segregated into 3 resistant （R）： 1 susceptible （S） or 1R：3S. The recessive R gene on chromosome 8 was further mapped to an interval ~1.9 cM/152 kb in length by linkage analysis with genomic position-ready markers in the mapping population derived from an F4 line that segregated into 1R：3S. Given that no major R gene was mapped to this inter- val, the novel R gene was designated as pi55（t）. Out of 26 candidate genes predicted in the region based on the reference genomic sequence of the cultivar Nipponbare, two genes that encode a leucine-rich repeat-containing protein and heavy-metalassociated domain-containing protein, respectively, were suggested as the most likely candidates for pi55（t）.
