Читать книгу Plant Pathology and Plant Pathogens - John A. Lucas - Страница 34

All crops are exposed to a wide variety of potentially pathogenic microorganisms present in soil, water, and the surrounding atmosphere. Yet most plants remain healthy most of the time. Consequently, the majority of pathogens are unable to infect the plants with which they come into contact. Even where a specific pathogen can attack a particular host species, there are marked variations in the extent to which individual plants succumb to disease. These differences are paralleled by variation in the pathogen population, reflecting differences in the genetic constitution of both the host and the pathogen. The ability of the pathogen to cause disease, and the host to respond to invasion, has been shown to be determined by specific genes. This discovery has important implications both in the analysis of disease and in its control.