Club Root in <i>Brassica</i> A Standard Inoculation Technique and the Specification of Races

Abstract

SUMMARY A simple and reliable technique for artificial inoculation of Brassica seedlings with Plasmodiophora brassicae is described. The technique is suitable for use in race surveys of the disease and in studies on the genetics of host resistance. A system of nomenclature of races, based on the use of B. napus differential genotypes of known genetic constitution, is outlined and results of pathogenicity tests with three races are presented.