Construction Of Genetic Map Using Genotyping Chips And QTL Analysis Of Plant Architecture

In order to carry out the QTLs of wheat plant architecture traits, in this study,quantitative trait loci(QTLs) for plant architecture traits were mapped using an available high-density 90 K wheat SNP and SSR genetic linkage map developed from a recombinant inbred line(RIL) population of “Zhou 8425 B × Xiaoyan 81”. An genetic linkage map was constructed by the software QTL lciMapping 4.0 and Mapchart 2.1, IBM SPSS statistics was used to analysis skewness and kurtosis of the plant architecture related traits. QTLs of different plant architecture traits were detected by inclusive composite interval mapping(ICIM)(LOD ≥ 2.5). The results have showed that:1. A genetic map of wheat covering wheat whole-genome was constructed and it contains6949 polymorphism markers, including 6910 SNP,36 SSR, covering 4839.9 cM, with an average interval distance of 0.70 cM. A, B and D chromsomes possess 2085, 4677, and 187 polymorphism markers, accounting for the proportion of 30%, 67.3%, and 2.7%, separately.The average interval distances of the markers were 0.99, 0.56 and 0.79 cM, respectively.2. Using phenotypic data on two locations(Yangling and Anyang) in two years(2013–2014 and 2014–2013 growing seasons), 40 QTLs for plant architecture traits were were mapped on chromosomes 1A, 2A, 3A, 4A, 5A, 7A, 1B, 2B, 3B, 4B, 5B, 6B, 7B and 2D with phenotypic variations ranging from 7.9 % to 30.5 %.3. The QTLs for Tiller angle(TA) were analyzed. 4 QTLs for TA located on chromosomes 1A, 3B and 5B were found explaining 10.39% ~ 15.83% of the phenotypic variances.4. The QTLs for flag leaf length(FLL), width(FLW) and area(FLA) were analyzed. 10 QTLs for FLL located on chromosomes 2A, 3B, 4B, 5A, 6B and 7B were found explaining7.9%~24.1% of the phenotypic variances. 4 QTLs were situated on chromosomes 2A, 3A and 5B, detected for FLW, explaining the phenotypic variations from 9.1%~16.5%. 8 QTLs for FLA were mapped on 2A, 3B, 4B, 5A, 6B and 7A chromosomes, accounting for 9.3%~30.5% of the phenotypic variation.5. QTL analysis on plant height(PH) in wheat were conducted. 4 QTLs for PH were checked out located on 1B, 5A, 5B and 6B chromosomes explaining 8.29%~19.74% of thephenotypic variances.6. QTL analysis on Internode length below spike(ILS), Top internode length(TIL),Internode length below spike/Top internode length(ILS/TIL), were conducted. 5 QTLs for ILS were detected on 1A, 2B, 4A chromosomes explaining 9.07 % ~ 17.08% of the phenotypic variances. 3 QTLs for TIL mapped on 2B, 3B and 7A chromosomes were found,accounting for 8.47%~19.70% of the phenotypic variation. 2 QTLs for ILS/TIL mapped on5 A and 2D chromosomes were found, accounting for 8.90 and 14.04% of the phenotypic variation.7. 6 QTL enrichment sections and multi-effect QTL were detected on 2A, 5A, 2B, 3B,5B and 6B chromosome. Two QTLs affecting ILS and TIL were found on 106 cM of 2B.3,and both of them were detected in more than one environment. Four QTLs affecting TA, FLL and FLW were found on 90 cM of 5B.3. Different traits of plant architecture have some correlativity, the genes controlling the related traits were more likely to form the genetic aggregation region, which might be the result of species evolution, and also provides a great convenience for polymerization breeding.