The genetic study utility of a hexaploid wheat DH population with non-recombinant A- and B-genomes

Ming Hao,Bo Zhang,Lianquan Zhang,Youliang Zheng,Wenjie Chen,Yuming Wei,Dengcai Liu,Huaigang Zhang,Jiangtao Luo,Zehong Yan,Jixiang Chen,Zhongwei Yuan

doi:10.1186/2193-1801-2-131

Abstract

To study the D-genome of the wild wheat relative Aegilops tauschii Cosson at the hexaploid level, we developed a synthetic doubled-haploid (DH) hexaploid wheat population, SynDH3. This population was derived from the spontaneous chromosome doubling of triploid F1 hybrid plants obtained from a cross between Triticum turgidum ssp. dicoccon PI377655 and A. tauschii ssp. strangulata AS66 × ssp. tauschii AS87. SynDH3 is a diploidization-hexaploid DH population containing recombinant D chromosomes from two different A. tauschii genotypes, with A and B chromosomes from T. turgidum being homogenous across the entire population. Using this population, we constructed a genetic map. Of the 440 markers used to construct the map, 421 (96%) were assigned to 12 linkage groups; these included 346 Diversity Arrays Technology (DArT) and 75 simple sequence repeat (SSR) markers. The total map length of the seven D chromosomes spanned 916.27 cM, with an average length of 130.90 cM per chromosome and an average distance between markers of 3.47 cM. Seven segregation distortion regions were detected on seven linkage groups. Out of 50 markers shared with those on a common wheat map, 37 showed a consistent order. The utility of the diploidization-hexaploid DH population for mapping qualitative trait genes was confirmed using the dominant glaucousness-inhibiting gene W2I as an example.Electronic supplementary materialThe online version of this article (doi:10.1186/2193-1801-2-131) contains supplementary material, which is available to authorized users.

Highlights

Common wheat, or bread wheat (Triticum aestivum L., 2n = 6x = 42, AABBDD), arose from the hybridization of T. turgidum L. (2n = 4x = 28, AABB) with the wild wheat relative Aegilops tauschii Cosson (2n = 2x = 14, DD)
Genetic map construction Because the only recombinant chromosomes in the DH population were those involving D-genomes derived from A. tauschii accessions AS66 and AS87, markers showing polymorphism between the two A. tauschii parents were used to genotype the DH population for genetic map construction
Based on the shared marks between our map with previous reported D-genome maps for common wheat (Somers et al 2004), the 12 linkage groups were assigned to 1D-7D chromosomes, respectively

Summary

Introduction

Genetic maps, based on amplified fragment length polymorphism (AFLP), restriction fragment length polymorphism (RFLP), microsatellite (SSR), and/or single-nucleotide polymorphism (SNP) markers, have been constructed for the A. tauschii D-genome using segregating populations derived from hybrids of A. tauschii accessions (Gill et al 1991; Boyko et al 1999; Ter Steege et al 2005; Luo et al 2009). Diversity Arrays Technology (DArT), which uses microarray hybridization to detect the presence or absence of DNA fragments, is a highly effective genetic mapping technology (Jaccoud et al 2001; Wenzl et al 2004; Akbari et al 2006). It has not been used for mapping of A. tauschii,

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