Construction Of Molecular Genetic Linkage Map And QTL Mapping Analysis Of Grain Length,Grain Width And Thousand Kernel Weight In Wheat

Wheat is one of the most important food crops in China.Many regions in China use wheat as a staple food.Common wheat is heterologous and hexaploid,contains A,B,D genomes.Polymorphisms rarely can be found between wheat varieties.Building high density of genetic linkage map construction and defining the wheat grain length,grain width and grain of the QTL on chromosome location and genetic effect is significant to the process of genetic improvement and breeding In this research,by applying the Illumina 90 K SNP assay,two high-density genetic linkage maps was constructed use two recombinant inbred lines(RILs)developed.Quantitative trait loci(QTL)of thousand grain weight(TGW),grain length(GL),grain width(GW),were identified.The main conclusions are as follows:(1)The results of grain length,grain width and thousand grain weight showed significant different among three parents,thus we built two RIL populations in order to identify QTL loci controlling grain length,grain width and thousand grain weight.The results of grain length,grain width and thousand grain weight showed significant different among three parents,thus we built two RIL populations in order to identify QTL loci controlling grain length,grain width and thousand grain weight.Traits skewness coefficient and group kurtosis coefficient of two RIL populations are less than 1,displays normal distribution.It indicated that the alleles control seeds shape randomly distributed on the parents’ chrosomes.(2)By using the RIL populations named Yanzhan 1 hao wheat/Yunnan wheat and Yanzhan 1hao wheat/Yuntian wheat to build wheat genetic linkage map.The two RIL populations’ genetic maps are built by using Illumina 90 K chip technology,Join Map and QTL ICI Mapping V3.2 software.Applying the Illumina 90 K SNP assay,two high-density genetic linkage maps were constructed use two recombinant inbred lines(RILs)developed.The genetic linkage map of Yanzhan 1 hao×Yunnanxiaomai contains 833 SNPs markers in a total coverage of 1517.86 cM with an average interval of 1.82 cM per marker.The genetic linkage map of Yanzhan 1 hao×Yutiandaomai contains 1115 SNPs markers in a total coverage of 1176.58 cM with an average interval of 1.06 cM per marker.(3)QTL for TGW,GL and GW were detected in six ecological environments(Taian,Dezhou and Heze)during two years between 2015-2016 by inclusive composite interval mapping(ICIM)(LOD≥2.5).A total of 12 QTLs of Yanzhan 1 hao×Yunnanxiaomai were identified,including two putative additive QTL and one multiple effect QTL loci.A total of 24 QTLs of Yanzhan 1 hao×Yutiandaomai were detected,including one putative additive QTL and three multiple effect QTL loci.