Sequence tagged microsatellites for the Xgwm533 locus provide new diagnostic markers to select for the presence of stem rust resistance gene Sr2 in bread wheat (Triticum aestivum L.)

摘要: The stem rust resistance gene Sr2 has provided durable broad-spectrum, adult-plant to the fungal pathogen Puccinia graminis Pers. f. sp. tritici throughout wheat-growing regions of world for more than 50 years. ability select in wheat breeding programs was recently improved by identification a tightly linked microsatellite marker gwm533. This typically amplifies 120-bp polymerase chain reaction fragment from lines carrying Sr2. In instances where is not associated with presence Sr2, DNA sequence analysis shown that second allele amplified, differing structure repeat. To discriminate this allelic homoplasy (alleles identical size, but descent), sequence-tagged microsatellites (STM) markers were developed Xgwm533 locus. These be diagnostic wide range germplasm, representative all major varieties historically grown Australia. STMs will particularly useful marker-assisted selection Southern Australian programs, use gwm533 often precluded non-Sr2-associated pedigree current germplasm. also revealed high incidence previously undetected at locus and may have broader utility genetic research breeding, as reported strongly conferring Fusarium head blight.