Introgression ofrpg4/Rpg5Into Barley Germplasm Provides Insights Into the Genetics of Resistance toPuccinia graminisf. sp.triticiRace TTKSK and Resources for Developing Resistant Cultivars

• DOI: 10.1094/phyto-09-18-0350-r
• Publication Date: 2019-02-04T15:08:43Z
• Authors: Javier Hernandez; Brian J. Steffenson; Tanya Filichkin; Scott P. Fisk; Laura Helgerson; Brigid Meints; Kelly J. Vining; David Marshall; Alicia del Blanco; Xianming Chen; Patrick M. Hayes
• Keywords: Stem rust; Germ plasm; Puccinia; Introgression

Stem rust (incited by Puccinia graminis f. sp. tritici) is a devastating disease of wheat and barley in many production areas. The widely virulent African P. tritici race TTKSK particular concern, because most cultivars are susceptible. To prepare for the possible arrival North America, we crossed range germplasm-representing different growth habits end uses-with donors stem resistance genes Rpg1 rpg4/Rpg5. former confers to prevalent races latter other closely related from Africa. We produced doubled haploids these crosses determined their allele type at Rpg loci haplotype 7,864 single-nucleotide polymorphism loci. were phenotyped seedling stage. Integration genotype phenotype data revealed that (i) was not associated with resistance, (ii) rpg4/Rpg5 necessary but sufficient (iii) specific haplotypes two quantitative trait required confer TTKSK. confirm whether lines found resistant also adult plant stage, subset evaluated Kenya. Additionally, leaf stripe hordei striiformis hordei, respectively) assessed on field trials three locations United States over 2-year period. Doubled identified all rusts, this germplasm available research breeding communities.