International Database for Barley Genes and Barley Genetic Stocks
BGS 751, Reaction to Puccinia graminis 7 (wheat
stem rust) , Rpg7
Stock number: BGS 751
Locus name: Reaction to Puccinia graminis 7 (wheat
Locus symbol: Rpg7
Previous nomenclature and gene symbolization:
Monofactorial dominant (1).
Located in chromosome 3HL (1); Rpg7.i is near the telomeric region of 3HL (1) between 135 and 155 cM based on the POPSEQ consensus map or between 667 and 693 Mbp based on the barley physical map.
The Rpg7.j gene confers moderate seedling resistance, Infection Types (ITs) 0;1 to 23, to a wide spectrum of domestic and foreign races of the wheat stem rust pathogen Puccinia graminis f. sp. tritici (Pgt) and also to an isolate of rye stem rust pathogen P. graminis f. sp. secalis (Pgs) (2). Accessions WBDC094 (ICARDA number: 40035 and USDA National Small Grains Collection number PI 681809) from Karak, Jordan and WBDC238 (ICARDA number: 40037; PI 681943) from Amman, Jordan were resistant as seedlings to Pgt race HKHJC in a greenhouse evaluation (2). Additional molecular and genetic studies revealed this gene to be novel; thus, a new locus designation, Rpg7, and an allele designation, Rpg7.i, were recommended (1, 2).
Origin of mutant:
Natural occurrence in wild barley (Hordeum vulgare subsp. spontaneum) accessions from Jordan, accession WBDC094 (ICARDA number: 40035; USDA number: PI 681809) from Karak and accession WBDC238 (40037; PI 681943) from Amman (2).
Rpg7.i in WBDC094 (ICARDA number: 40035; USDA number: PI 681809) from Karak, Jordan and WBDC238 (40037; PI 681943) from Amman, Jordan (1, 2).
Mutant used for description and seed stocks:
Rpg7.i in WBDC094 (ICARDA number: 40035; USDA number: PI 681809) and WBDC238 (ICARDA number: 40037; PI 681943).
1. Henningsen, E., O. Matny, T. Szinyei, A. Sallam, and B.J. Steffenson. 2020. Rpg7: A new gene for stem rust resistance from wild barley, Hordeum vulgare ssp. spontaneum. Phytopathology XX:XXXX.
2. Sallam, A.H., P. Tyagi, G. Brown-Guedira, G.J. Muehlbauer, A. Hulse, and B.J. Steffenson. 2017. Genome-wide association mapping of stem rust resistance in Hordeum vulgare subsp. spontaneum. G3: Genes, Genome, Genetics 7:3491.
E. Henningsen and B.J. Steffenson. 2018. Barley Genet. Newsl. 48:180