Construction Of An Integrated High-Density Genetic Map Based On SNP And SSR Markers In Wheat

Bread wheat（Triticum aestivum L.）is one of the most important crops worldwide.Breeding the varieties with high yield,high quality and multiple stresses resistance is the common goal for wheat breeders.The application of marker-assisted selection（MAS）has greatly accelerated the breeding process.MAS technology requires high-density genetic map to identify the underling genes or quantitative trait loci（QTL）of target traits.Therefore,the construction of a high-density genetic map of wheat is substantially important.In this study,a recombinant inbred line（RIL）(F_8:9)population including 131 lines was used to construct a high-density genetic map by using wheat 90K SNP iSelect chip and SSR markers.The genetic map contains 10,858 SNP markers and 216 SSR markers,2,038 of which are non-co-segregated markers,covering 3,584 cM of the total length of the 21 wheat chromosomes.The average genetic distance between the markers was 0.32 cM.Further analysis of the map found that the A,B and D sub-genomes contain 3,741（33.8%）,6,091（55%）and 1,242（11.2%）markers,respectively.The average genetic distance among the A,B and D sub-genomes is 0.38 cM,0.21 cM and 0.71 cM,respectively.The frequency of segregation distortion（SD）in this map is relatively low,and segregation distortion regions（SDRs）have the characteristics of being clusters and most of the direction in segregation distortion regions is the same.The construction of this high-density genetic map can provide a powerful tool for marker-assisted selection of wheat.