Identification Of Leaf Rust Resistance Genes In Chinese Wheat Landraces And QTL Analysis To Leaf And Stripe Rusts Resistance Of W014204 Wheat RILs

Wheat rust is one of the main diseases endangering wheat yield in China.Since the founding of the People’s Republic of China,wheat leaf rust and stripe rust have experienced many epidemics,causing serious economic losses.At present,the most healthy,economical and effective way to control the disease is to plant disease-resistant varieties.This study mainly includes two parts:resistance gene identification to leaf rust in wheat landraces and QTL analysis of adult plants resistance to leaf and stripe rusts of W014204:In the first part,at the seedling stage,19 different leaf rust physiological races with different virulence were inoculated,and 36 differentials(mostly NILs)containing known leaf rust resistance gene and Chinese wheat landraces to be tested were inoculated.The infestation type deduced the leaf rust resistance genes that may be contained in the tested varieties.At the same time,molecular markers closely linked to known leaf rust resistance genes were used to verify the gene postulation results.At the adult stage,inoculated with strong virulent leaf rust mixed physiological races,field investigation severity and prevalence,and selected slow rust varieties according to national industry standards.Comprehensive gene postulation and molecular marker detection methods.8 leaf rust resistance genes were detected in 71 wheat landraces.Among them,5 varieties contain Lr1;1 variety contains Lr10;1 variety contains Lr13;1 variety contains Lr14b;8 wheat varieties contain Lr26;17 varieties contain Lr34;5 varieties contain Lr37;20 varieties contain Lr46.Based on the data from two years of field investigation,27 slow-rust varieties were screened.In the second part,WO 14204 was introduced to CIMMYT,which has good resistance to wheat leaf rust and stripe rust in the field.Therefore,it is expected that this cultivar contains adult rust resistance genes.A total of 214 recombined inbred lines(RILs)derived from W014204/Zhengzhou 5389 were included in 2015-2016 and 2016-201 7 cropping seasons.All these RILs annually were planted in Baoding,Hebei province,and Mianyang,Sichuan province,and in 2018-2019 cropping season planting in Mianyang.Sichuan province.Artificial inoculation of mixed physiological races of Puccinia striiformis f.sp.tritici and investigation of the final severity.On the other hand,they were also planted in Zhoukou,Henan province and Baoding,Hebei province in the 2018-2019 cropping seasons,and inoculated with a mixed Puccinia triticina Eriks races.A total of 5 QTL loci were mapped in this study.Among them,the QTL locus on 1BL was resistant to leaf rust and stripe rust,explaining 9.7%-16.2%of the phenotypic variation.The locus detected was Lr46/Yr29.Stripe rust resistance QTL locus on chromosome 2A was detected in three strip rust environments,which explained 6.4%-7.6%of the phenotypic variation.After analysis,this site was considered to be a new adult strip rust resistance QTL locus.The leaf rust resistance QTL locus located on the 2BS chromosome was detected in two leaf rust environments,explaining 8.8%-14.2%of the phenotypic variation,which was analyzed to be Lr48.The stripe rust resistance QTL locus located on the 5BL chromosome was detected in three strip rust environments,which explained the phenotypic variation of 6.7%-7.2%.Whether this locus is a new stripe rust-resistant QTL site needs further verification.The leaf rust resistance QTL located on the 5BL chromosome was detected in two leaf rust environments,which explained a phenotypic variation of 8.4%-9.7%.It was considered that this site was a new QTL locus for resistance to leaf rust.In summary,this study detected 8 known leaf rust resistance genes in 71 wheat landraces,and screened 27 slow rust varieties,which can provide a basis for the selection and utilization of resistance sources in the future;in the WO14204/Zhengzhou 5389RIL population five QTL loci for leaf rust resistance and stripe rust resistance of adult plants were located in.After analysis,there are 2 new QTLs for rust resistance in adult plants,which can lay the foundation for fine mapping and map-based cloning in the future.