Validation of molecular markers for wheat breeding

Five sets of markers were assessed for their usefulness in breeding, two linked to wheat stem rust gene Sr2 , several markers linked to a chromosome segment conferring Yr17/Lr37/Sr38 resistance, two reported markers for the linked genes Lr35 and Sr39 , one for Lr28 , and one linked to flour colour. The gene for Sr2 confers adult plant resistance to stem rust ( Puccinia graminis f.sp. tritici ) and was originally transferred to bread wheat from the tetraploid emmer (‘Yaroslav’) to the cultivars Hope and H-44. The gene is located on the short arm of chromosome 3B and confers a durable adult plant resistance to stem rust usually expressed only in the field. The chromosome segment carrying the Lr37 , Sr38 , Yr17 resistance genes is located on 2AS and was originally introduced into wheat through an Aegilops ventricosa Triticum persicum cross, followed by a cross to the cultivar Marne (VPM1). The flour colour quantitative trait locus was originally described in a Yarralinka Schomburg cross and is located on chromosome 7A. The primers as originally developed required optimisation for more routine use in a breeding program.