Preliminary Locating Study On QTL Mapping In Grain Related Traits And Anti-Powdery Mildew In Wheat

Wheat is one of the leading crops in our country.Achieving higher yields and robust resistance is the important goal for wheat breeding.In the research,an advanced genetic map of wheat yield traits was constructed using high-throughput 35K DArT chip scanning material and a population of 184 recombinant inbred lines(RILs),which were derived from wheat with high resistance to powdery mildew cultivars"CH1532" and susceptible wheat powdery wildew cultivars "Taichang 29".We analyzed gain characters,explored the genetic model of wheat CH1532,mapped the poedery mildew resistance genes in wheat"CH1532" by composite interval mapping(CIM).The closely linked makers could faciliate the fine mapping of resistance genes and marker assist selection(MAS)breeding and pyramid breedingThe main results were summarized here1.The high throughput markers of 36420 DArTs were essential for the construction of genetic maps.A genetic map covering all of the 21 wheat chromosomes was established.The map spanned a tatal length of 6087.313cm,with an average density of 1.5cm/marker.The distribution of DAr markers are uneven in different chromosomes,for example,B>A>D.B genome has the most abundant DArT loci,containing 1773 DArT loci and contributing to 43.8%.2.QTL mapping for Grain plumpness,size and Kernel hardness:(1)Nine QTL loci located in five chromosomes,including 4B,5A,5D,6A and 7A were detected,for grain plumpness.Single QTL could explain 5.17%-16.74%of the phenotypic variation.Qgplu-5A controlling heading date in three environments,had 13.71%,9.91%and 16.74%of contribution rate,and 0.43,0.36 and 0.48 of additive effects,respectively,The synergistic effects of Qgplu-5A came from the female parent "CH1532".(2)Fourteen QTL loci located in six chromosomes,including 2B,3A,3B,5D,6A and 7B,were detected,for grain size.Single QTL could explain 5.24%-11.28%of the phenotypic variation.Qgsh-6A controlling heading date in three environments,had 9.66%,9.96%and 11.28%of contribution rate,and-0.19,-0.2 and-0.21 of additive effects,respectively,The synergistic effects of Qgsh-6A came from the male parent"Taichang29".(3)Ten QTL loci located in seven chromosomes,including 1B,2D,5D,5B,6D,6A and 7Dwere detected,for grain hardness.Single QTL could explain 4.47%-27.09%of the phenotypic variation.Qpm-IB controlling heading date in three environments,had 27.09%,20.37%and 20.59%of contribution rate,and 0.27,0.23 and 0.23 of additive effects,respectively.The synergistic effects of Qpm-IB came from the female parent "CH1532".3.Nine QTL loci located in six chromosomes,includinglB,2B,4B,4D,5A and 6A,were detected,for powdery mildew.Single QTL could explain 4.49%-12.56%of the phenotypic variation.Qpm-IB controlling heading date in two environments,had 12.56%and 9.57%of contribution rate,and-0.41 and-0.38 of additive effects,respectively,The synergistic effects of came from the male parent "Taichang29".