Ms3 dominant genetic male sterility for wheat improvement with molecular breeding

Abstract

AbstractGenetic dominant male sterility (DMS) has not been widely used as a breeding tool in wheat (Triticum aestivum L.), although DMS‐facilitated backcross, mass selection, half‐sib selection, and S1 family recurrent selection strategies have been described, and Ms2‐facilitated recurrent selection has been used in China. Our objective was to revisit these strategies using the tools of molecular breeding. Development of a mechanism for seedling identification of sterile progeny was a key component of designing practical DMS‐facilitated molecular breeding systems. The DMS gene Ms3 was previously localized to the centromeric region of chromosome 5A. The centromeric location is an advantage because recombination rates are very low. Once identified, a broadly informative marker would reliably predict the male‐sterile phenotype. A set of 429 hybrids incorporating Ms3 were constructed, both within US hard winter wheats, and between these winter wheats and Asian spring wheats. Association of the male‐sterile phenotype with those polymorphic DNA sequence tags that localized to chromosome 5A was tested using case‐control association analysis. Two highly significant (logarithm of odds [LOD] > 30) single nucleotide polymorphism (SNP)–trait associations were obtained. One SNP was developed into a highly sensitive, reliable marker for the Ms3‐associated male‐sterile phenotype. Previously described breeding strategies using DMS were updated for trait‐targeted marker‐assisted backcrossing and gene pyramiding, S1 recurrent selection, and early‐generation genomic selection. Application of DMS to association mapping, with the particular use case of the multiparent advanced generation intercross population, is also described.