IDENTICAL GENES FOR VIRULENCE IN THE SMUTS USTILAGO HORDEI AND U. NIGRA, AND INHERITANCE OF VIRULENCE ON THE BARLEY CULTIVARS KEYSTONE AND CONQUEST

Abstract

Virulence of Ustilago hordei (Pers.) Lagerh. and U. nigra Tapke on the barley (Hordeum vulgare L.) cultivars Keystone and Conquest was studied. One recessive gene or linked genes, the same in both smut species, appeared to confer virulence on both cultivars. Earlier investigators had found identical virulence genes in both species of smut for the cultivars Excelsior, Lion, Pannier and Trebi. Therefore, testing for resistance or susceptibility in a breeding program could be done with a strain of only one of the species.