VIEW ARTICLE

Genetics

Genetic Control of Ethirimol Resistance in a Natural Population of Erysiphe graminis f.sp. hordei. D. W. Hollomon, Rothamsted Experiment Station, Harpenden, Herts., U.K.; Phytopathology 71:536-540. Accepted for publication 30 October 1980. Copyright 1981 The American Phytopathological Society. DOI: 10.1094/Phyto-71-536.

Resistance in field isolates of Erysiphe graminis f. sp. hordei to the fungicide ethirimol is controlled, not by one major gene, but by a complex heritable system in which the genetic factors involved are primarily additive. Particularly favorable gene combinations established in resistant genotypes may be broken through recombination, leading to some breakdown of resistance. No evidence was obtained for linkage between resistance to ethirimol and three virulence genes in the pathogen. The implications of the use of ethirimol in disease control strategies are discussed.