Mapping stripe rust resistance genes by BSR-Seq: YrMM58 and YrHY1 on chromosome 2AS in Chinese wheat lines Mengmai 58 and Huaiyang 1 are Yr17

Stripe rust (yellow rust), caused by Puccinia striiformis f. sp. tritici (PST), is one of the most devastating fungal diseases in common wheat (Triticum aestivum L.) in China and worldwide. Resistance breeding is the most effective strategy to control diseases in crop plants. Chinese wheat lines Mengmai 58 and Huaiyang 1 are highly resistant to PST race CYR34 (V26) at the adult plant stage. To genetically map the underlying resistance genes we developed segregating populations by crossing Mengmai 58 and Huaiyang 1 with the susceptible cultivar Nongda 399. The stripe rust resistances in Mengmai 58 and Huaiyang 1 were both controlled by single dominant genes, provisionally designated YrMM58 and YrHY1, respectively. Bulked segregant RNA-Seq (BSR-Seq) analysis showed that YrMM58 and YrHY1 were located in the same distal ~ 16 Mb region on chromosome 2AS. Comparative genomics analysis with the physical map of Aegilops tauschii proved useful for developing additional markers to saturate the genetic linkage map. YrMM58 and YrHY1 were mapped to the distal end of chromosome arm 2AS, with the closest marker WGGB148 being 7.7 cM and 3.8 cM from the resistance gene, which was considered to be Yr17. These markers can be used in marker-assisted selection.