Genetic and cellular mechanisms regulating plant responses to necrotrophic pathogens.

Necrotrophs are plant pathogens that kill host cells and proliferate on nutrients from dead or dying tissues causing devastating diseases of horticultural and agronomic crops. Their interactions with plants involve a complex network of pathogen disease factors and corresponding plant immune response regulators. Mechanisms of quantitative resistance and the major regulators intersect regardless of pathogen life style. By contrast, some plant immune responses, such as effector-triggered immunity (ETI), a major source of qualitative resistance to biotrophs, are co-opted by necrotrophs to promote disease, which highlights the disparate plant immunity systems. Advances towards understanding mechanisms and processes underlying host responses to necrotrophs are summarized.