Kenya Kudu/郑州5389 F2∶3群体成株期抗叶锈基因QTL定位OA

Kenya Kudu,a Kenyan wheat variety,exhibits robust adult plant resistance(APR)to leaf rust.To dissect the genetic architecture underlying this resistance,we conducted quantitative trait lo-cus(QTL)mapping using 195 F2∶3 lines derived from a cross between Kenya Kudu and the susceptible cultivar Zhengzhou 5389.Field evaluations were carried out in Baoding,Hebei Province and Zhoukou,Henan Province during the 2017-2018 and 2018-2019 growing seasons.Plants were inoculated with a mixture of virulent Puccinia triticina(Pt)races to assess APR.Phenotypic data on disease severity were integrated with genotypic data from 660K SNP array and SSR markers for QTL analysis.The results demonstrated that three novel adult plant resistance QTLs to leaf rust were identified on wheat chromosomes 2B and 5B.Two QTLs were located on chromosome 5B,provisionally designated as QLr.hbau-5B.1 and QLr.hbau-5B.2,accounting for 8.3～10.5％and 6.9～8.6％of the phenotypic variation,respectively.One QTL located on chromosome 2B,provisionally designated QLr.hbau-2B,accounted for 7.2～10.6％of the phenotypic variation and may correspond to a known leaf rust resistance locus.These results demonstrate that Kenya Kudu's resistance is attributed to the additive effects of multiple minor-effect QTLs.The identified QTLs and their closely linked molecular mark-ers offer critical genetic tools for marker-assisted selection(M AS)in breeding wheat cultivars with du-rable resistance to leaf rust.