Development Of The Chromosome Segment Substitution Lines Derived From The Reciprocal Genetic Background Of Changhui121 And Koshihikari And Mapping Of Major QTL For Grain Shape Traits

In this study,two sets of chromosome segment substitution lines(CSSLs)of Koshihikari,and Chang Hui 121,as reciprocal genetic background were constructed.The major results are as follows:(1)A total of 180 pairs of SSR primers evenly distributed on all 12 chromosomes were selected.The location,order and distance of the 180 pairs of SSR primers were determined according to a molecular marker linkage map constructed by McCouch et al.The map covered the whole genome 1427.7cM,average spacing 7.93 cM.The CSSL population of Changhui 121 genetic background contained 98 lines.The replacement tag number molecular markers for each plant is 8.85 in average,4.92% percent.Among them,the number of donor homozygous genotype mark is 4.21,and 4.64 marks are heterozygous genotype.The CSSL population of Koshihikari genetic background contained 107 lines.The replacement tag number molecular markers for each plant is 9.79 in average,5.44%percent.Among them,the number of donor homozygous genotype mark is 4.70,and 5.09 marks are heterozygous genotype.(2)QTL substitution mapping.In order to restore the Changhui 121 background chromosome segment substitution lines were detected in the grain length associated with ten chromosome fragments.Nine chromosome fragments associated with grain width.Ten chromosome fragments associated with grain weight.Including six QTL clusters sector:chromosome 1 RM6387-RM5362 might focus on the control of grain length and grain width QTL;chromosome 2 RM8252-RM1092 may control grain type and grain weight QTL;chromosome 5 RM7444-RM2998 may control grain type and grain weight QTL;chromosome 7 RM5752-RM7110 may control grain length and grain weight;chromosome8 RM4085-RM6990 may control grain type and grain weight and the chromosome 10RM2125-RM5708 may control grain type and grain weight.(3)Comparison with previous studies.Region on chromosome 1 is repeated multiple testing at the period also grain length segment may have,suggesting there should be an enrichment for grain type and grain weight QTL,but has not yet been cloned.Substitution segment at RM3646 on chromosome 3,and close to GS3 and a negative effect on grain length,is likely to be the same one.The same section of chromosome 5 was repeatedly detected,with the value of further research.Chromosome 10 came less studied,are located on the grain weight and grain shape QTL more in the long arm of the end,this study found that the region is located on the short arm near the centromere,there has no relevant reports.