Development Of Functional KASP Markers For Wheat Stripe Rust Resistance Gene YrAs2388 And Pyramiding Of Genes For Multiple Disease Resistance In Wheat

Wheat(Triticum aestivum)is one of the most important cultivated cereal crop in the world,the production of wheat is seriously threaten by various fungal diseases,which seriously affected the yield and quality.At present,a large number of disease resistance genes have been identified from wheat and its relatives,and few of them have been successfully cloned,while a minority of them have been successfully applied in wheat resistance breeding.Nowadays,the identification of more effective disease resistance genes and the enhancing resistance durability as well as developing cultivars with multiple disease resistance are important strategies for Chinese wheat resistance breeding.The pyramiding of different disease resistance genes can effectively improve the crop resistance level and durability.To effectively control the main wheat diseases in China,we have developed molecular markers and used them to pyramid disease resistance genes and create wheat germplasm resistance to multiple wheat pathogens,and provide wheat materials for wheat long-term broad-spectrum resistance breeding.The main results of this study are as follows:We have developed the functional kompetitive allele specific PCR(KASP)markers for the stripe rust resistance gene Yr AS2388.Two gene-specific KASP markers(KASP-E5 与 KASP-E6’)for Yr AS2388 were obtained by comparing multiple homoeologous and paralogous genomic sequences of Yr AS2388 alleles from wheat and its relatives reference genomes.These two markers(KASP-E5 与 KASP-E6’)were validated in different types of wheat populations including segregation population of Yr AS2388,Aegilops tauschii,synthetic hexaploid wheat,and wild emmer wheat,and common wheat.The results showed that KASP-E5 can effectively distinguish the heterozygous and homozygous genotypes of Yr AS2388,and KASP-E6’ can be used for the identification a functional type Yr AS2388.Our results indicate that KASP-E5 and KASP-E6’ are perfect diagnostic markers for Yr AS2388 and would be useful for marker assisted selection in wheat resistance breeding.1.We have pyramided YrAS2388,Yr36,Pm21,and Fhb1 and obtained lines confer resistance to diverse wheat pathogens.The Mianmai367(Pm21),Chuanmai64R4(Fhb1),h130-2-8(Yr36+Yr AS2388)carrying different resistance genes were crossed each other to pyramid the disease resistance genes.The gene-specific markers were used to identify gene pyramids.Finally,F4 generations which carring four genes(Yr36+Yr AS2388+Fhb1+Pm21),three genes(Yr AS2388+Fhb1+Pm21,Yr36+Fhb1+Pm21)and two genes(Fhb1+Pm21)were obtained.We have selected elite lines by disease resistance and agronomic traits evaluation,which provided materials for breeding of multi-resistant wheat cultivars.Taken together,our study provided ideal molecular-assisted selection markers for wheat durable multi-resistant breeding and created novel wheat germplasm with durable and broad-spectrum resistance.