Types Of Commercial Wheat Variety HWM-GS And Their Association With Quality Traits

Wheat is an important food crop,and its processing quality mainly depends on the content and composition of storage proteins.High molecular weight glutenin which has primary influence on wheat processing quality is an important component of seed storage protein.In order to compare the genetic diversity at Glu-1 locus,508 commercial wheat varieties from 7 provinces in China were used to identify their high molecular weight glutenin subunits(HMW-GS)in this study.After that,the cluster analysis and quality evaluation were performed,and then the correlation between HMW-GS and grain quality traits was analyzed to provide reference for the genetic improvement of wheat quality.The main results are as follows:1.HMW-GS composition types: 16 different subunit types were detected in 508 wheat germplasm resources.Three subunit types were detected at Glu-A1 locus: 1(64.17%),2*(1.57%)and Null(34.25%);nine subunit types were detected at Glu-B1locus: 7(2.95%),7+8(34.06%),7+9(46.65%),6+8(0.98%),13+16(0.98%),13+19(1.18%),14+15(9.25%),17+18(3.54%)and 7*+8(0.39%).Four subunit types were detected at Glu-D1 locus: 2+12(50.39%),5+10(44.09%),2+10(0.98%),5+12(4.53%).At the same time,there were some differences in subunit types among different provinces.Among them,subunit 1 was the widespread subunit type in 6 provinces;and subunit 7+8was the dominant subunit in Shanxi,Shaanxi and Anhui provinces;7+9 is the dominant subunit in Henan Province;2+12 was the dominant subunit in Hebei,Shaanxi and Shanxi;and 5+10 was the dominant subunit in Shanxi,Jiangsu and Anhui.In addition,there were also some differences in the subunit types of varieties with different breeding years.At the Glu-A1 locus,the subunits 1 of varieties bred in 1990～2000,2001～2010 and2011～2022 were dominant subunits,with frequencies of 57.69%,73.64% and 62.50%,respectively.At the Glu-B1 locus,the frequency of 7+8 subunit decreased gradually in the three varieties,which were 57.69%,32.73% and 30.36%,respectively,while the frequency of 7+9 subunit increased gradually,which were 26.92%,41.82% and 55.36%,respectively.At Glu-D1 locus,the frequency of 2+12 subunit was highest in 1990～2000and 2011～2022,which was 65.38% and 58.93%,respectively,while the frequency of5+10 subunit was highest in 2001～2010,which was 50.91%.2.HMW-GS combination types: 39 different subunit combination types were detected in 508 wheat germplasm resources.The frequency of subunit combination1/7+9/5+10 was the highest(13.78%),followed by 1/7+9/2+12(13.39%),N/7+9/2+12(12.20%)and 1/7+8/5+10(11.02%).And the subunit combinations of varieties in different provinces were also different,among which N/7+9/2+12 was the dominant subunit combination in Hebei Province;1/7+9/5+10 was the dominant subunit combination in Henan Province;N/7+8/5+10 was the dominant subunit combination in Shandong Province;1/7+8/2+12 was the dominant subunit combination in Shaanxi Province;1/7+8/5+10 was the dominant subunit combination in Jiangsu and Anhui;N/7+9/2+12 is the dominant subunit combination in Shanxi Province.Among different breeding years,the dominant subunit combinations were also different.The frequency of subunit combination 1/7+8/2+12 was the highest(26.92%)in 1990～2000,the frequency of subunit combination 1/7+9/5+10 was the highest(17.27%)in 2001～2010,and the frequency of subunit combination N/7+9/2+12 was the highest(20.54%)in 2011～2022.3.Genetic diversity analysis of Glu-1 locus: The genetic diversity indexes of 508 wheat germplasm resources were as follows: average number of alleles(A)=5.33,percentage of polymorphic loci(P)=1.00,effective number of alleles per locus(Ae)=2.337 and genetic diversity index(H)=0.558.The genetic diversity index of Shanxi Province and Hebei Province was relatively high,H=0.579 and H=0.570,respectively.The genetic diversity index of Shaanxi Province and Anhui Province was low,H=0.458 and H=0.453,respectively.In addition,the genetic diversity index of varieties in different breeding years was 2001～2010(H=0.542)>2011～2022(H=0.531)>1990～2000(H=0.527).4.Cluster analysis and score of HMW-GS combination: 508 wheat materials were divided into three categories based on the similarity of Glu-1 locus alleles.Class I contained 29 wheat germplasms and 9 subunit combinations.Class II contained 204 wheat germplasms and 12 subunit combinations.Class III contained 275 wheat germplasms and 18 subunit combinations.Among them,the average quality score of class II was the highest(8.92 points),followed by class I(8.87 points)and class III(6.67points).5.Association analysis between HMW-GS and quality traits: Eight quality traits of469 wheat germplasms were analyzed.The results showed that the highest starch content was 60.44% in Shanxi Province and the lowest was 58.77% in Shandong Province.The highest protein content was 12.58% in Shandong Province and the lowest was 11.30% in Shanxi Province.The highest wet gluten content was 28.15% in Shandong Province and the lowest was 24.39% in Shanxi Province.The largest value of Zeleny sedimentation was 22.72 m L in Shandong Province,but the smallest was 15.76 m L in Shanxi Province.Different HMW-GS types had different effects on quality traits.Among them,2*,17+18,7*+8 and 5+10 subunits and N/7+8/5+10 subunit combinations significantly promoted the improvement of protein content,wet gluten content and Zeleny sedimentation value.It’s worth noting that,cultivars No.Y108 and Y151 showed excellent performance in protein content,wet gluten and Zeleny sedimentation value.