Mapping And Validation Of QTL For Grain Size,Grain Weight,stigma Exsertion And Brown Rice Protein

The grain shape of rice（which can be decomposed into grain length,grain width and grain thickness）has a very important influence on the 1000-grain weight and appearance quality of rice.1000-grain weight is an important factor determining rice yield,and the appearance quality,that determines the commercial value of rice.With the improvement of the quality of life,people pay more and more attention to the nutritional quality of rice,and the brown rice protein content is closely related to the quality of rice.The stigma exsertion rate of rice is an important factor affecting the outcrossing rate of rice,which in turn affects the seed production of hybrid rice and restricts the commercialization of hybrid rice.This study used high-density sequencing technology to quantify quantitative trait loci（QTL）related to rice grain shape,thousand grain weight,brown rice protein content,stigma exsertion rate,heading date,plant height and brown rice rate using two recombinant inbred lines（RILs）.1. Using the the large-grain japonica rice variety of Anhui Academy of Agricultural Sciences rice research institute,Yangdao 6 Xuan（YD6-X）,and the indica-type photo-temperature-sensitive genic male sterile line 1892S were crossed and then by multi-generation selfe-crossing,a recombination inbred lines（RILs）poupulation content136 familys were constructed.The genetic marker linkage map of the RILs population was constructed using SNP and INDEL markers developed by genotyping by sequceing（GBS）technology.The total number of markers in the genetic map was 43,175,the total number of bins was 1563,the total length was 1545.64c M,and the average distance between markers was 0.03c M.Using SNP/INDEL markers in F₆（2016）and F₇（2017）,we detected 8 QTLs related to grain length,and these QTL distributed on chromosomes 1,2,4,6,7 and 8,with 2 QTL was repeatedly detected within two years;7 QTLs related to grain width were detected,distributed on chromosomes 2,4,7,9 and 11,with 2 QTL were repeatedly detected within two years;8 QTL related to grain thickness were detected,distributed on chromosomes 1,2,4,7 and 9,with 3 QTL are repeatedly detected within two years;10 QTL related to 1000-grain weight were detected,distributed on chromosomes 1,2,4,7 and 9,with 2 QTL were repeatedly detected within two years;4QTL related to heading date were detected,distributed on chromosomes 5,7 and 12,only1 QTL was repeatedly detected within two years;7 QTL related to single stigma exsertion rate were detected,distributed on chromosomes 1,2,4,5,7 and 8,only 1 QTL was repeatedly detected in two years;4 QTL related to the double stigma exsertion rate were detected,distributed on chromosomes 1,3,4 and 7,with 2 QTL were repeatedly detected in two years;5 QTL related to the total stigma exsertion rate were detected,distributed on chromosomes 1,2,3,4 and 7,only 1 QTL was repeatedly detected in two years;3 QTL related to brown rice protein content were detected,distributed on chromosomes 2,7 and9;5 QTL related to plant height were dectded and distributed on chromosomes 2,3,6,7and 9;5 QTL related to brown rice rate were detected and distributed on chromosomes 2and 9.2. The hybrid rice cultivar RH003 and the indica-type photo-thermophilic genic male sterile line 1892S,which were bred by the Rice Research Institute of Anhui Academy of Agricultural Sciences,were crossed and then by multi-generation self-crossing,and a total of 192 families of recombinant inbred lines（RILs）population were constructed.The genetic marker linkage map of the RILs population was constructed using SNP and INDEL markers developed by GBS technology.The total number of markers in the genetic map was 39,379,the total number of bins was 1,550,the total length was 1244.48c M,and the average distance between the markers was 0.03 c M.Using SNP/INDEL markers in F6（2016）and F7（2017）,we detected 8 QTL related to grain length,and these QTL distributed on chromosomes 1,2,3,6,9,11 and 12,only 1 QTL were repeatedly detected within two years;8 QTL related to grain width,distributed on chromosomes 2,3,4,6,7,10 and 12,with 4 QTL were repeatedly detected within two years;10 QTL related to grain thickness,distributed on chromosomes 1,2,3,7,11 and 12,with 3 QTL were repeatedly detected within two years;7 QTL related to 1000-grain weight,distributed on chromosomes 1,2,3,7,with 3 QTL were repeatedly detected within two years;5 QTL related to heading date,distributed on chromosomes 6,7,8,and 11,with 2 QTL were repeatedly detected within two years;6 QTL related to brown rice protein content,distributed on chromosomes 2,6,7,8,9,and 12;1 QTL associated with brown rice rate was distributed on chromosome 7;7 QTL related to plant height,distributed on chromosomes 2,6,7,8,and 9.3. Using the recombined inbred line population,the remaining heterozygous lineages of 13 QTL loci were screened and constructed,and the effect was verified.Among them,the qTGW2.1 locus in the 1892S/YD6-X population verified the effect in the grain length and grain width direction;the q TGW1.1 in the 1892S/RH003 population verified the effect in the grain length direction,and q GW4.2 in the grain length The effect was verified in the grain width direction.