摘要
Soil flooding stress,including seed-flooding,is a key issue in soybean production in highrainfall and poorly drained areas.A nested association mapping(NAM)population comprising 230 lines of two recombinant inbred line(RIL)populations with a common parent was established and tested for seed-flooding tolerance using relative seedling length as indicator in two environments.The population was genotyped using RAD-seq(restriction site-associated DNA sequencing)to generate 6137 SNPLDB(SNP linkage disequilibrium block)markers.Using RTM-GWAS(restricted two-stage multi-locus multiallele genome-wide association study),26 main-effect QTL with 63 alleles and 12 QEI(QTL×environment)QTL with 27 alleles in a total of 33 QTL with 78 alleles(12 dual-effect alleles)were identified,explaining respectively 50.95%and 14.79%of phenotypic variation.The QTL-alleles were organized into main-effect and QEI matrices to show the genetic architecture of seed-flooding tolerance of the three parents and the NAM population.From the main-effect matrix,the best genotype was predicted to have genotypic value 1.924,compared to the parental value range 0.652–1.069,and 33 candidate genes involved in six biological processes were identified and confirmed byχ2 test.The results may provide a way to match the breeding by design strategy.
基金
This work was financially supported by the National Key Research and Development Program of China(2016YFD0100201,2017YFD0101500,2017YFD0102002)
the National Natural Science Foundation of China(31571694,31671718,31571695)
the MOE 111 Project(B08025)
the MOE Program for Changjiang Scholars and Innovative Research Team in University(PCSIRT_17R55)
the MARA CARS-04 Program,the Jiangsu Higher Education PAPD Program,the Fundamental Research Funds for the Central Universities(KYT201801)
the Jiangsu JCIC-MCP.The funders had no role in work design,data collection and analysis,and decision and preparation of the manuscript.
