Genetic Mapping of a Novel Gene PmAege7M from Aegilops geniculata Conferring Resistance to Wheat Powdery Mildew.

Powdery mildew, caused by Blumeria graminis f. sp. tritici ( Bgt ), is one of the most damaging foliage diseases of wheat across the world. Aegilops geniculata Roth is a valuable gene resource for enhancing wheat resistance to powdery mildew. This study identified Ae . geniculata accession PI 487224 as immune and PI 487228 as susceptible to powdery mildew. Genetic analysis of the F ₁ , F ₂ , and F _2:3 progeny derived from PI 487224 × PI 487228 showed that powdery mildew resistance in PI 487224 was controlled by two independent dominant genes located on two different nonhomologous chromosomes. By combing bulked segregant RNA-Seq, genetic linkage analysis of a single resistance gene segregation population, and marker analysis of a set of 14 wheat- Ae . geniculata chromosome addition lines, one of the resistance genes, temperately designated PmAege7M , was mapped to a 4.9-cM interval flanked by markers STS7-55926 and SNP7-45792/STS7-65911 on the long arm of chromosome 7 M ^g of PI 487224, spanning 604.73 to 622.82 Mb on the 7D long arm based on the Ae. tauschii reference genome (Aet_v4.0). The map and closely linked markers of PmAege7M from Ae . geniculata in this study will facilitate the transfer of PmAege7M into common wheat and fine mapping of the gene.
Competing Interests: The author(s) declare no conflict of interest.