International Database for Barley Genes and Barley Genetic Stocks
BGS 319, Reaction to Puccinia graminis 4 (wheat stem rust), rpg4
Stock number: BGS 319
Locus name: Reaction to Puccinia graminis 4 (wheat stem rust)
Locus symbol: rpg4
Previous nomenclature and gene symbolization:
Monofactorial recessive (3, 4).
Located in chromosome 5HL (1); rpg4.d is in the central part of 5HL about 4.9 cM distal from RFLP marker MWG740 (1).
The rpg4.d gene confers low infection types to pathotypes QCC and MCC of the wheat stem rust pathogen (Puccinia graminis f sp tritici ) at the seedling stage under low incubation temperatures 18 to 22oC (3, 4). This gene is ineffective (exhibits compatible infection types) against some pathotypes at incubation temperatures greater than 27oC. At the adult plant stage, the rpg4.d allele confers a moderate to high level of resistance to pathotype QCC (2). The rpg4.d gene confers a dominant resistant reaction to Puccinia graminis f sp secalis (5).
Origin of mutant:
Natural occurrence in Q21861 (PI 584766) from Centro Internacional de Mejormiento de Maize y Trigo (ICARDA-CIMMYT barley breeding program) and identified by Dill-Macky and Rees at Toowoomba, Australia, but its pedigree cannot be traced (3).
rpg4.d in Q21861 (GSHO 2438, PI 584766) (3).
Mutant used for description and seed stocks:
rpg4.d in Q21861 (GSHO 2438).
1. Borovkova, I.G., B.J. Steffenson, Y. Jin, J.B. Rasmussen, A. Kilian, A. Kleinhofs, B.G. Rossnagel, and K.N. Kao. 1995. Identification of molecular markers linked to the stem rust resistance gene rpg4 in barley. Phytopathology 85:181-185.
2. Jin, Y., B.J. Steffenson, and T.G. Fetch, Jr. 1994. Sources of resistance to pathotype QCC of Puccinia graminis f. sp. tritici in barley. Crop Sci. 34:285-288.
3. Jin, Y., B.J. Steffenson, and J.D. Miller. 1994. Inheritance of resistance to pathotypes QCC and MCC of Puccinia graminis f. sp. tritici in barley line Q21861 and temperature effects on the expression of resistance. Phytopathology 84:452-455.
4. Steffenson, B.J., Y. Jin, B.G. Rossnagel, and K. Kao. 1995. Genetics of multiple disease resistance in a doubled haploid population of barley. Plant Breed. 114:50-54.
5. Sun, Y., B.J. Steffenson, and Y. Jin. 1996. Genetics of resistance to Puccinia graminis f. sp. secalis in barley line Q21861. Phytopathology 86:1299-1302.
Y. Jin and B.J. Steffenson. 1995. Barley Genet. Newsl. 24:169.
B.J. Steffenson and J.D. Franckowiak. 1997. Barley Genet. Newsl. 26:267.