Substitution Mapping of Quantitative Trait Loci for Seed Shattering in Chromosome Segment Substitution Lines of Rice (Oryza sativa L.)
利用染色体片段置换系定位水稻落粒性主效QTL

Seed shattering plays an important role in rice breeding. Using an indica variety 93-11, a japonica variety Nipponbare and seven chromosome segment substitution lines (CSSLs ) with a genetic background of 93-11 introgressed from Nipponbare as the materials, we investigated seed shattering with 153 simple sequence repeat (SSR) markers on rice chromosomes , the introgressed segment and the quantitative trait loci (QTL) for seed shattering. Among the SSR markers , 104 displayed polymorphism bands between two parents, and the rate of polymorphism was 68.0%; among the CSSLs, the seed shattering of four was the same as for Nipponbare, and that of the other three was the same as for 93-11. Four CSSLs had four introgressed segments on rice chromosome 1 and three had three introgressed segments on rice chromosome 6. The genetic distance for the seven introgressed segments was 23.6, 16.5, 6.6, 9.9, 10.4, 20.2 and 7.1 cM, respectively; qSH-1-1 was mapped in the region of RM472-RM1387, with 6.6 cM genetic distance on rice chromosome 1. qSH-6-1 was mapped in the region of RM6782-RM3430, with 4.2 cM genetic distance on rice chromosome 6. The QTL for seed shattering in rice can be mapped primarily by use of CSSLs. Mapping the QTL has laid a foundation for fine mapping and cloning the QTL and molecular marker-assisted selection of appearance quality in rice.