VIEW ARTICLE

Resistance

Genetics of Resistance to Stem Rust in Thirteen Wheats of Diverse Origins. F. J. Gough, Research plant pathologist, Agricultural Research, SEA, U.S. Department of Agriculture, Oklahoma State University, Stillwater 74078; O. G. Merkle(2), and A. P. Roelfs(3). (2)Research agronomist, Agricultural Research, SEA, U.S. Department of Agriculture, Oklahoma State University, Stillwater 74078; (3)Research plant pathologist, Cereal Rust Laboratory, Agricultural Research, SEA, U.S. Department of Agriculture, University of Minnesota, St. Paul 55108. Phytopathology 70:897-899. Accepted for publication 7 March 1980. This article is in the public domain and not copyrightable. It may be freely reprinted with customary crediting of the source. The American Phytopathological Society, 1980. DOI: 10.1094/Phyto-70-897.

Inheritance of seedling resistance to culture 111-SS2 of Puccinia graminis f. sp. tritici was studied in crosses of 13 resistant wheat (Triticum aestivum and T. turgidum) cultivars and selections with susceptible T. aestivum ‘Little Club’. The resistant wheats included: Gai Printemps, Docteur Mazet, Primepi, Opal, Cleo, Kenya Page, Kenya Hunter, Webster, Ninguta 157, D7314, N4, a T. turgidum selection, and a Triticum sp. selection. Resistance was conditioned by one gene in the T. turgidum selection, by two genes in Docteur Mazet and D7314, by four genes in Primepi; and by three genes in each of the remaining wheats. Genes for resistance were dominant and independent in all crosses. Lines derived from each cross also were tested with 24 additional cultures. A comparison of the reaction of each line with those of 66 tester stocks having known genes for resistance indicated that Opal, Kenya Page, Kenya Hunter, and Triticum sp. have Sr7b; Docteur Mazet and Triticum –sp. have Sr10; D7314 has Sr15; Kenya Page and Kenya Hunter have Sr17; Gai Printemps, Docteur Mazet, Primepi, Opal, Cleo, Kenya Page, Kenya Hunter, and Ninguta 157 have Sr18; and Webster has Sr30. The unidentified genes conditioned intermediate levels of resistance to a narrow array of biotypes of P. graminis F. sp. tritici. Consequently, their value in current U.S. breeding programs appears to be limited.