Pathogens, regulation host plant resistance

Alterations of Physiology. Susceptible plant species or cultivars may be rendered resistant to disease by so altering their physiology, e.g., hormonal balances, ion fluxes, constitutive secondary metabolism, or respiratory rates, as to render them unfit or hostile environments for pathogen development, i.e., to make them non-hosts. This could be accomplished, for example, by the use of growth regulators or breeding. 

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