| Wheat is the largest grain crop in the world.The cultivated area of wheat in China has stabilized at about 360 million mu in recent years,among which the Huang-Huai wheat region is the main producing area and high producing area.High-yield and water-saving varieties is an important task of wheat breeding in this region.In this study,272 wheat varieties(lines)developed in the Huang-Huai wheat region in recent years were collected to identify yield traits and drought resistance.Transcriptome sequencing was performed,and genome-wide association analysis was performed based on phenotype identification and RNA-seq analysis.The main results are as follows:(1)Identification of yield and drought resistance characters in wheat.Eleven yield characters and drought resistance of 272 wheat varieties(lines)were identified.Variation analysis showed that there was a large variation(5.53%～98.10%)in each character,the highest variation in the number of sterile spikelets(TSS)at the top and the lowest variation in the number of total spikelets(TSS).The heritability of each character is large(52.51%～82.94%).Correlation analysis showed that there was significant or extremely significant negative correlation between the three factors of yield.Jimai22 was used as the control to screen out the top 30 excellent varieties(lines)of each traits.Based on the drought resistance coefficient and drought resistance index of plant height,yield and yield,29 drought resistant varieties(lines)such as Zhoumai28 were screened out.(2)Transcriptome sequencing was performed on 272 test materials,12,650,150,333 Clean Reads were obtained,and 1,687,861 original markers were obtained by variation analysis.The original markers were screened according to MAF≥5% and U≤50%,and 176,357 markers were obtained,including 163,223 SNPs and 13,134 In Del.(3)The genome-wide association analysis of yield traits showed that 966 markers were significantly associated with the stability of yield traits in wheat,which were distributed on all21 chromosomes and could explain 4.69%～21.39% of the phenotypic variation.Among them,detected with plant height,ear length,ear Numbers per spike,grain number,and the total number of spikelets,basal sterile spikelet number,at the top of the sterile spikelet number,fertile spikelet number,sterile spikelet number,grain yield significantly associated tag respectively 127,91,55,49,52,61,58,43,81,75,100,50,54 and 70.The 7 markers of S＿093223,S＿093225,S＿093226,S＿093226,S＿093226,S＿093304,S＿093314,S＿093425,and S＿093439 were significantly correlated with 3 or more traits at the same time,and they were pleiotropy markers.(4)In the genome-wide association analysis of drought resistance,a total of 207 markers were detected that were significantly associated with drought resistance coefficient of plant height,drought resistance coefficient of panicle number,drought resistance coefficient of grain number per panicle,and drought resistance coefficient of 1000-grain weight.They were distributed on 19 chromosomes except 6D and 7D,and could explain 4.70%～13.22% of the phenotypic variation.Among them,94,19,69 and 25 markers were significantly associated with the drought resistance coefficient of plant height,number of ears per mu,number of grains per ear and 1000-grain weight,respectively. |
