小麦品种(系)主要农艺性状的遗传多样性分析及综合评价OA

To establish a comprehensive evaluation system for wheat parental lines and to screen breeding materials with superior genetic characteristics,in this study,50 wheat cultivars(lines)were taken as experimental materials.Eight agronomic traits including plant height(PH),spike length(SL),number of spikelets per spike(NSPS),number of grains per spike(NGPS),number of effective tillers per plant(NETP),grain texture(GT),grain uniformity(GU),and thousand-grain weight(TGW)were measured.Comprehensive genetic diversity analysis and evaluation were performed by calculating the genetic diversity index,conducting correlation analysis,principal component analysis(PCA),applying the membership function method,and performing hierarchical clustering.The results indicated the range of genetic diversity index for the eight traits was from 0.37(GT)to 2.07(SL),with an average of 1.62,demonstrating that the 50 wheat varieties(lines)had substantial genetic diversity.The coefficients of variation(CV)for the traits varied from 5.46％to 30.27％.Notably,NETP exhibited the highest CV(30.27％),suggesting that the population had the highest level of diversity in the number of effective tillers per plant and the greatest improvement space.Correlation analysis revealed a extremely significant positive correlation between SL and NSPS(r=0.451),as well as between SL and NGPS(r=0.475).A significant positive correlation was also found between NSPS and NGPS(r=0.329).Through the dimensionality reduction technique in multivariate statistical methods,8 original phenotypic parameters were integrated into 5 mutually uncorrelated comprehensive variables,and their cumulative contribution rate reached 82.05％,which could effectively characterize the systematic variation characteristics of the original dataset.Hierarchical clustering based on comprehensive evaluation values of membership function method classified the 50 varieties(lines)into five groups:excellent type,better type,middling type,poor type,and worst type.Six elite materials inclduing Jimai 55,Yannong 836,Jingyang 670,Luyuan 158,Xinmai 296,and Tainong 108 were identified as superior parental materials for breeding.