Genome-wide Association Studies Of Quality Traits Sedimentation Value In Wheat

Wheat is one of the important main grains in China.As one of the quality characters of wheat,sedimentation value has an important influence on wheat breeding and food processing.Sedimentation value is one of the important indexes to evaluate wheat gluten content,which is closely related to bread volume,dough formation and stabilization time.Therefore,it is of great significance for wheat breeding and quality improvement to study the sedimentation value and its genetic law.In this paper,we used 660 k gene chip genotyping,through the collection of 493 wheat core germplasm materials for the whole genome association analysis of sedimentation value,through 2 years in 3 regions and 5 environments for planting and flour sedimentation value measurement,using the whole genome association analysis to analyze the control mechanism of sedimentation value inheritance.The main results are as follows:(1)The population structure of the tested materials is suitable for association analysis,and the genetic relationship is far away,only 43 materials are close to each other,belonging to the natural population,and the materials conforming to the whole genome association analysis account for 92% of the total materials,laying a foundation for the accuracy and reliability of the results.(2)The characteristics of wheat sedimentation value varied widely among the 493 materials in the experiment,and the frequency distribution was normal.A few materials had a large sedimentation value in five environments,such as Shaanyou 225.Under Shandong(SD)and Shaanxi(SX)environment,the quality of wheat was significantly improved compared with other three environments,and the variation of SX environmental sedimentation value was the largest,which was basically the same in other environments.(3)In genome-wide association analysis,SNP loci with strong genetic effect were found on chromosomes 1A,1B,1D,6A and 7D,such as AX94929872,AX86180188,AX94876256,AX110052107,AX110459663,AX111793464,AX108747296 AND AX108912374,among which AX108912374 appeared many times under different analysis conditions.These loci coincide with the key genes of wheat quality,such as high molecular weight glutenin,lowgrain glutenin and prolamin,which are important genetic loci of quality genes.(4)After standardizing the table data and filling in the missing data with tassel5.0,the SNP loci obtained by correlation analysis with mixed linear model were used for excellent allelic variation analysis.It was found that six loci with stable correlation with precipitation value were detected in two or more environments,namely ax108747296-a,ax94877770-t,ax110052107-g,ax111793464-c,Ax94876256-t and ax94929872-a,respectively,increased the sedimentation value by 1.87 ml,2.10 ml,1.99 ml,1.98 ml,2.05 ml and 2.02 ml.The SNP loci detected in this study provide a theoretical basis for assisted selection breeding and quality improvement of wheat at the molecular level,and lay a foundation for the development of functional genes controlling the quality characteristics of wheat.