Inheritance Analysis And Genetic Mapping For A Stripe Rust Resistance Gene In New Wheat Germplasm N07168

Wheat is an important food crop.Stripe rust caused by Puccinia striiformis f.sp.Tritici is one of the most serious diseases in wheat production.Studies have shown that breeding wheat varieties resistant to stripe rust is one of the most economical and effective means.However,with the rapid variability of psts,genes resistant to stripe rust are often difficult to maintain for a long time.Therefore,broadening the wheat disease resistance spectrum and exploring broad-spectrum resistance genes will be the key to solving this problem in the future.The new wheat germplasm N07168 was selected from the cross of Shanyou225 and synthetic wheat SE5799.The agronomic traits are good and the disease resistance is also strong.Therefore,the new wheat germplasm N07168 was used as a material to study the inheritance of its stripe rust resistance gene in order to provide theoretical support for broadening wheat stripe rust resistance resources and achieve long-term prevention of disease occurrence.The main results obtained by this study are as follows:1.The identification results showed that the new wheat germplasm N07168 was highly resistant to the tested psts.Both major genes plus polygenes analysis and Chi-square analysis of disease resistance in F2 and F2:3 populations obtained by crossing the new wheat germplasm N07168 with the susceptible variety Xinong979 showed that the resistance of the new wheat germplasm N07168 to CYR32 and CYR33 mixed strains was regulated by one pair of dominant genes.2.Through the nulli-tetrasomic analysis,Yr N07168 was mapped to chromosome 1B.The reliability of this was confirmed by screening of SSR molecular markers.3.Eleven molecular markers closely linked to the resistance gene were obtained,including one SNP marker,two EST markers,and eight SSR markers.The genetic map of Yr N07168 was drawn accordingly.The total span of the genetic linkage map was 81.34 c M.The two closest flanking markers were Xwmc626 and Xbarc55,with a distance of 1.65 c M and 6.17 c M,respectively.Through the preliminary analysis of disease resistance spectrum,combined with the molecular marker identification,Yr N07168 might be a new disease resistance gene.It laid a theoretical foundation for further analysis of the site of action of this gene and the subsequent map-based cloning.