Rmg13 and Rmg14, Novel Wheat Blast Resistance Genes Identified in the NBRP-Wheat Hexaploid Core Collection.

Wheat blast, a devastating disease originally confined to South America, has spread to Asia and Africa, raising serious concerns about global food security. By screening hexaploid wheat accessions collected worldwide, we identified two accessions that showed resistance to wheat blast even under high-temperature conditions and at the heading stage: a Triticum aestivum accession from Ethiopia (KU-7356) and a T. spelta accession from Spain (KU-1062). Genetic analyses revealed that resistance in each accession was controlled by a single gene. The resistance genes in KU-7356 and KU-1062 were mapped to chromosome arms 4AL and 5AL and designated Rmg13 and Rmg14, respectively. Both genes conferred strong resistance to South American isolates but moderate to weak resistance against Bangladeshi isolates. Rmg13 and Rmg14 will complement the resistance provided by 2NS and Rmg8, and pyramiding these genes holds strong potential for developing wheat cultivars with enhanced and durable resistance to wheat blast.