Genetics of Virulence in Californian Populations ofBremia lactucae(Lettuce Downy Mildew)

Publisher Website
Google Scholar
Abstract
Virulence phenotypes and sexual compatibility types were determined for 116 Californian isolates of Bremia lactucae collected between 1982 and 1986 [from Lactuca sativa, growing areas]. All but one isolate could be grouped into one of three distinct pathotypes on the basis of their virulence phenotypes. Sexual compatibility type (SCT) was absolutely correlated with pathotype. All pathotype I isolates had the B1 SCT, and all pathotype II and III isolates had the B2 SCT. The genetic basis of avirulence was also studied for representative isolates of each pathotype. The avirulence genotypes and the lack of diversity in virulence phenotype suggested that the sexual cycle has not been important in the generation of variation in the Californain population of B. lactucae. This may have been because of the infertility of matings between the predominant pathotypes.

This publication has 1 reference indexed in Scilit: