Great achievements have been madein breeding of semidwarf varieties(indica) since 1960s. Resultsshowed that the dwarf traits widelyused .at present were controlled by thesame recessive major gene, sd-1,thus we faced t...Great achievements have been madein breeding of semidwarf varieties(indica) since 1960s. Resultsshowed that the dwarf traits widelyused .at present were controlled by thesame recessive major gene, sd-1,thus we faced the potential danger oflosing genetic diversity. The low yield展开更多
Genetic analysis established that Aitaiyin3,a dwarf rice variety derived from a semidwarf cultivar Taiyin1,carries two recessive semidwarf genes.By using simple sequence repeat(SSR)markers,we mapped the two semidwarf ...Genetic analysis established that Aitaiyin3,a dwarf rice variety derived from a semidwarf cultivar Taiyin1,carries two recessive semidwarf genes.By using simple sequence repeat(SSR)markers,we mapped the two semidwarf genes,sd-1 and sd-t2 on chromosomes 1 and 4,respectively.Sd-t2 was thus named because the semidrawf gene sd-t has already been identified from Aitaiyin 2 whose origin could be traced back to Taiyin1.The result of the molecular mapping of sd-1 gene revealed it is linked to four SSR markers found on chromosome 1.These markers are:RM297,RM302,RM212,and OSR3 spaced at 4.7 cM,0 cM,0.8cM and 0 cM,respectively.Sd-t2 was found to be located on chromosome 4 using five SSR markers:two markers,SSR332 and RM1305 located proximal to sd-t2 are spaced 11.6 cM,3.8 cM,respectively,while the three distally located primers,RM5633,RM307,and RM401 are separated by distances of 0.4 cM,0.0 cM,and 0.4 cM,respectively.展开更多
The semidwarf gene sd-g which has been used in indica rice breeding in southern China is a new one, non-allelic to sd-1. To map sd-g, an F2 population derived from the cross between Xinguiaishuangai and 02428 was con-...The semidwarf gene sd-g which has been used in indica rice breeding in southern China is a new one, non-allelic to sd-1. To map sd-g, an F2 population derived from the cross between Xinguiaishuangai and 02428 was con-structed. The sd-g was roughly mapped between two mi-crosatellite markers RM440 and RM163, with genetic dis-tances of 0.5 and 2.5 cM, respectively. Then nine new poly-morphic microsatellite markers were developed in this region. The sd-g was further mapped between two microsatellite markers SSR5-1 and SSR5-51, with genetic distances of 0.1 and 0.3 cM, respectively, while cosegregated with SSR418. A BAC contig was found to span the sd-g locus, the region be-ing delimited to 85 kb. This result was very useful for cloning of the sd-g gene.展开更多
文摘Great achievements have been madein breeding of semidwarf varieties(indica) since 1960s. Resultsshowed that the dwarf traits widelyused .at present were controlled by thesame recessive major gene, sd-1,thus we faced the potential danger oflosing genetic diversity. The low yield
基金supported by the National Natural Science Foundation of China (No.30270705 and 3990086)the National High Technology Program (No.2003CB114303).
文摘Genetic analysis established that Aitaiyin3,a dwarf rice variety derived from a semidwarf cultivar Taiyin1,carries two recessive semidwarf genes.By using simple sequence repeat(SSR)markers,we mapped the two semidwarf genes,sd-1 and sd-t2 on chromosomes 1 and 4,respectively.Sd-t2 was thus named because the semidrawf gene sd-t has already been identified from Aitaiyin 2 whose origin could be traced back to Taiyin1.The result of the molecular mapping of sd-1 gene revealed it is linked to four SSR markers found on chromosome 1.These markers are:RM297,RM302,RM212,and OSR3 spaced at 4.7 cM,0 cM,0.8cM and 0 cM,respectively.Sd-t2 was found to be located on chromosome 4 using five SSR markers:two markers,SSR332 and RM1305 located proximal to sd-t2 are spaced 11.6 cM,3.8 cM,respectively,while the three distally located primers,RM5633,RM307,and RM401 are separated by distances of 0.4 cM,0.0 cM,and 0.4 cM,respectively.
文摘The semidwarf gene sd-g which has been used in indica rice breeding in southern China is a new one, non-allelic to sd-1. To map sd-g, an F2 population derived from the cross between Xinguiaishuangai and 02428 was con-structed. The sd-g was roughly mapped between two mi-crosatellite markers RM440 and RM163, with genetic dis-tances of 0.5 and 2.5 cM, respectively. Then nine new poly-morphic microsatellite markers were developed in this region. The sd-g was further mapped between two microsatellite markers SSR5-1 and SSR5-51, with genetic distances of 0.1 and 0.3 cM, respectively, while cosegregated with SSR418. A BAC contig was found to span the sd-g locus, the region be-ing delimited to 85 kb. This result was very useful for cloning of the sd-g gene.