Patterns of infection in plant pathogen systems.

摘要

Four major factors are potentially responsible of patterns of infection in plant pathogen systems: (1) stochastic processes; (2) spatial dynamics; (3) micro-habitat requirements; (4) disease resistance. I attempted to identify the processes responsible of patterns of infection in the plant Phlox paniculata infected with the powdery mildew pathogen Erysiphe cichoracearum. I monitored the spatial dynamics of infection and constructed a spatial map of disease resistance in a natural population. Both the pattern of infection and the pattern of disease resistance were spatially clumped. To determine the processes responsible for the pattern of disease resistance, I constructed a spatial map of relatedness in the same plant population mapped for resistance using AFLP markers. Relatedness was spatially clumped, but the clumps of relatedness did not correspond to the clumps of resistance. This indicates that selection by the pathogen is probably responsible for the spatial patterns of disease resistance, not simply plant dispersal capabilities.