Potential applications of molecular markers for genetic analysis of host–pathogen systems in forest trees

Abstract

Applications of molecular markers for genetic analysis of host–pathogen systems are presented within the framework of the gene-for-gene model. The literature on complementary genetic interactions in host–pathogen systems is briefly reviewed. Flor's gene-for-gene hypothesis is summarized, and the design, execution, and genetic interpretation of experiments to test this hypothesis are described in detail. Various molecular techniques that have been used to complement the traditional gene-for-gene approach are also briefly reviewed. Three alternative approaches to developing molecular markers using the gene-for-gene framework are presented to illustrate the potential for applying molecular markers in forest tree–pathogen systems. Two of these alternative approaches allow partial confirmation of a hypothesized gene-for-gene genetic model without the usual requirement for advanced pedigrees. Such alternative approaches could greatly accelerate the development of marker-aided selection for disease resistance in forest tree–pathogen systems.