International Database for Barley Genes and Barley Genetic Stocks

BGS 733, Required for Puccinia graminis resistance 4, rpr4

BGN  46:142
Stock number: BGS 733
Locus name: Required for Puccinia graminis resistance 4
Locus symbol: rpr4

Previous nomenclature and gene symbolization:

γ08-114; R36-37#1 (3, 4).


Monofactorial recessive (2, 3, 4).
Location is unknown.


The rpr4.d mutant induced a moderate susceptible reaction to Puccinia graminis Pers.:Pers. f. sp. tritici Eriks. E. Henn (Pgt) race MCCF in the cultivar, Morex, having the Rpg1.a gene (see BGS 511) for resistance to P. graminis (wheat stem rust). The rpr4.d mutant has been partially characterized (2, 3) with an infection type (IT) of moderately susceptible (MS): IT range of 21 to 32 with a mode 32 (rated by 1); IT range of 3- to 3+ (rated by 2, 3), or IT range of 3.3+ to 3.3- (rated by 6) based on a 0-4 scale, defined by Stakman et al. (5). The parent line Morex is rated as moderately resistant. For description of IT ratings, see the BGS description for rpr2 (BGS 731). The rpr4.d mutant is not allelic to rpr1.a, rpr2.b, rpr3.c, rpr5.e, or rpr6.f (2, 3, 4). The RPG1 protein is present and apparently functional as indicated by the observations that the RPG1 protein was phosphorylated within 15 min of inoculation with Pgt race MCCF urediniospores and degraded within 24 hrs of infection as expected for a functional RPG1 protein (2, 3, 4).
No images

Origin of mutant:

rpr4.d (γ08-114; R36-37#1, GSHO 3697) in Morex (CIho 15773) (3, 4).

Mutational events:

rpr4.d (γ08-114; R36-37#1, GSHO 3697) in Morex (CIho 15773) (3, 4).

Mutant used for description and seed stocks:

rpr4.d (γ08-114; R36-37#1, GSHO 3697) in Morex (4).


1. Brueggeman, R.S. (Unpublished).

2. Gill, U.S. 2012. Understanding and characterizing the genes associated with Rpg1 mediated resistance pathway against stem rust. Ph.D. Thesis. Washington State University, Pullman.

3. Gill, U., R. Brueggeman, J. Nirmala, Y. Chai, B. Steffenson, and A. Kleinhofs. 2016. Molecular and genetic characterization of barley mutants and genetic mapping of mutant rpr2 required for Rpg1-mediated resistance against stem rust. Theor. Appl. Genet. 129 (8):1519-1529.

4. Kleinhofs, A. (Unpublished).

5. Stakman, E.C., D.M. Steward, and W.Q. Loegering. 1962. Identification of physiologic races of Puccinia graminis var. tritici. U.S. Dep. Agric. ARS E-617.

6. Steffenson, B.J. (Unpublished).


A. Kleinhofs. 2015. Barley Genet. Newsl. 45:245.


A. Kleinhofs. 2016. Barley Genet. Newsl. 46:142.