Marker assisted breeding for introgression of striperust resistance in wheat Triticum aestivum L

Abstract

newline Striperust,causedbyPucciniastriiformisf.sp.tritici,posessignificantthreattowheat crop.Enhancingwheatyieldwithimprovedresistanceisamajorconcern.Genepyramidingaided bybackcrossingandprecisemarkerassistedselectionisanefficientstrategy forplantbreeders to address the issue. The study entitled Marker-assisted breeding for introgression of stripe rust resistanceinwheat(Triticumaestivum L.) wasstrategicallydesignedtocharacterize Yrgenesin resistant genotypes, identify and pyramid effective Yr genes into adapted susceptible wheat genotypes followed by marker-assisted identification of wheat lines carrying genes of interest. Seven genotypes were found resistant, withACI andAUDPC ranging from 1 to 3 and 15 to 100, respectively. The distribution of 12 Yr genes in 48 wheat genotypes of diverse origin, identified effective resistance genes Yr16 and Yr26 in 10 and 40 genotypes, respectively. Introgression of Yr16 and Yr26 into adapted susceptible wheat genotypes through repeated backcrossing and marker-assistedforegroundselectioninbackcrosspopulationsoffourcrossesusingXgwm102and Xgwm498,linkedtoYr16andYr26respectively.CrossesA(RSP561×Tusie)andB(PBW175× Tusie)targetingtheYr16geneidentifiedtwoandthreeplants,respectivelywithresistancegenein heterozygouscondition.CrossC(JAUW584×Trophy)andD(PBW175×Trophy)targetingthe Yr26 gene identified three and five plants, respectively in heterozygous condition. BC2F2populationofcrossAand crossBidentifiedfourandthreehomozygous resistantlines,respectively for Yr16 gene. Similarly, cross C and cross D identified 12 and 16 homozygous/heterozygous resistantlines,respectivelyforYr26gene.SevenplantswithtwoYrgenes(Yr16+Yr26)in(PBW 175 × Tusie) × (PBW 175 × Trophy) showed pyramiding indicating successful introgression of effective Yr genes that can serve as donors for breeding stripe rust resistance in wheat.