Genetics And Molecular Mapping Of Stripe Rust Resistance Gene(S) In Several Wheat Cultivars(Lines)

Stripe rust is one of the most important diseases of wheat worldwide，the developmentand deployment of cultivars with genetic resistance is the most effective, economical andenvironment friendly way to reduce yield losses due to stripe rusts.The main point of this research were:identification and mapping QTL for high-temperature adult-plant (HTAP) resistance and seedling resistance to stripe rust (Pucciniastriiformis f. sp. tritici) in the winter wheat (Triticum aestivum L.) cultivar ‘Druchamp’；Stripe rust seedling resistance genetic analysis of three Triticum aestivum-Haynaldia villosatranslocation lines, molecular mapping of two all-stage seedling stripe rust resistance genesin two of these three translocation lines;Stripe rust seedling resistance genetic analysis of fivewheat-P. huashanica Keng translocation lines.The result were:1.Multilocation field trials, single nucleotide polymorphism (SNP) and simple sequencerepeat (SSR) markers were used to identify quantitative trait loci (QTL) for stripe rust high-temperature adult-plant(HTAP) resistance and all stage seedling resistance gene in Druchamp.Composite interval mapping (CIM) identified four stable HTAP resistance QTLQYrdr.wgp-1BL.2，QYrdr.wgp-2BL，QYrdr.wgp-5AL and QYrdr.wgp-5BL.1, which locatedon chromosome1BL,2BL,5AL and5BL, respectively, explaining2.36-31.04%,2.81-15.65%,3.24-17.22%and2.42-15.13%of the phenotypic variance, respectively,the nearestmolecular marker of these QTLs was SNP marker: Xiwa8581, Xiwa7583, Xiwa2558andXiwa6383, separately.Four HTAP resistance QTL were also identified across part of theseenvironment:QYrdr.wgp-1BL.1,QYrdr.wgp-1DS, QYrdr.wgp-3AL and QYrdr.wgp-6BL,which located on chromosome1BL,1DS,3AL and6BL, respectively, explained1.94–10.19%,2.04–27.24%,1.78–13.85%and1.69-21.63%of the phenotypic variance, respectively,thenearest molecular marker was：SSR marker Xgwm131，SNP marker Xiwa2268，Xiwa6834and Xiwa6420, respectively.Three seedling resistance QTL were identified located on chromosome5BL (QYrdr.wgp-5BL.2),5DL(QYrdr.wgp-5DL) and6BL(QYrdr.wgp-6BL.2)， explained separately5.47–36.04%,9.27–11.94%and13.07–20.36%of the phenotypic variance, of which the nearestmolecular marker was SNP marker Xiwa6271，Xiwa8331and Xiwa3297, respectively. All these QTLs and their closely linked molecular markers could be used in wheat cultivarsmarker-assisted selection breeding for improving resistance to stripe rust.2．Stripe rust seedling resistance genetic analysis result of three Triticum aestivum-Haynaldia villosa translocation lines were: V9128-1resistance to CYR30, CYR32andSun11-4were all controlled by one dominant gene, resistance to CYR31were controlled byone dominant gene and one recessive gene, independently; single dominant gene conferringresistance to these four dominant races (or single spore strains) in V9128-3; the resistance ofV3against CYR29was conferred by two dominant genes, independently, one dominant geneand one recessive gene conferring independently or a single dominant gene to conferresistance to CYR31, two complementary dominant genes conferring resistance to bothCYR32and Sun11-4, two independently dominant genes or three dominant genes (two of thegenes show cumulative effect) conferring resistance to CYR33,a single dominant gene forresistance to Sun11-11.Bulk segregant analysis (BSA) method and molecular markertechnique were used to do molecular mapping, two markers Xgwm356and Xwmc658locatedon2AL from219SSR primer combinations were found linked to YrHV(temporarilydesignated), the dominant gene for resistance to Sun11-4in V9128-3, which was8.5cM fromXgwm356and5.6cM from Xwmc658, respectively; A linkage map of2RGAP and7SSRmarkers was constructed for the single dominant gene (temporarily designated as YrV3) forresistance to Sun11-11in V3, the linkage map spanned a genetic distance of25.0cM, theSSR markers Xgwm124and Xcfa2147closely linked to YrV3with genetic distances of3.0and3.8cM, respectively.3. To study the genetics of the stripe rust resistance in five wheat-P.huashanica Kengtranslocation lines, these five translocation lines, susceptible cultivar Mingxian169and theirF1, F2, BC1F1and F3cross generations were tested with Pst races under controlled greenhouseconditions, the result showed: For H9015-17-1-9-6, the resistance to race CYR32and CYR33all were controlled by a single dominant gene; for H9014-14-4-6-1, the resistance to raceSu11-4was controlled by a single dominant gene, to race CYR33was controlled by a singlerecessive gene; H9020-1-6-8-3resistance to CYR33was controlled by one dominant gene;the resistance of H9014-27-1-3-5-5against CYR23and Sunll-4was conferred by twodominant genes, independently, against CYR32and CYR33all were controlled by a singledominant gene; single dominant gene conferring resistance to these four dominant races(Sunll-4, CYR29, CYR31and CYR32) in H122.