Identification of Sr genes in new common wheat sources of resistance to stem rust race Ug99 using molecular markers

Abstract

The need for new donors of resistance to the aggressive Ug99 race of Puccinia graminis Pers. f. sp. tritici Eriks. et Henn has arisen because the pathogen is approaching the territory of the Russian Federation. Seventeen known Sr genes were identified with the use of molecular markers in 6 sources of resistance to stem rust race Ug99. They included five common wheat lines and the Donskaya Polukarlikovaya cv. The investigated accessions carried genetic material of alien species (Aegilops speltoides, Ae. triuncialis, and Secale cereale). We used molecular markers associated with the effective genes to the Ug99 race: Sr2, Sr22, Sr24, Sr25, Sr26, Sr32, Sr35, Sr36, Sr39, Sr40, Sr44, and Sr47, and with genes that were ineffective but protected the wheat cultivars against the local pathogen populations: Sr9a, Sr15, Sr17, Sr19, and Sr31. On the grounds of the analysis of molecular markers the presence of two to seven known Sr genes was postulated in the analyzed wheat lines: Sr2, Sr36, Sr39, Sr40, Sr44, Sr47, and Sr15 in line 113/00i-4; Sr22, Sr32, Sr44, Sr9a, Sr17, and Sr19 in line 119/4-06rw; Sr24, Sr36, Sr40, Sr47, Sr15, Sr17, and Sr31 in line GT 96/90; and Sr22, Sr44, Sr32, and Sr15 in line 9/00w; Sr22 and Sr44 in line 141/97w. Genes Sr32 and Sr44 were identified to be effective against Ug99 and ineffective genes Sr9a, Sr17, and Sr19 in Donskaya Polukarlikovaya cv. The accessions studied may be recommended as donors of resistance to race Ug99 in wheat breeding programs.