Suppressor Production as a Key Factor for Fungal Pathogenesis
Plants are endowed with diverse mechanisms that protect them from pathogenic microorganisms. Active defense, including formation of many chemical and physical barriers (e.g., phytoalexin, infection inhibitor, pathogenesis related proteins, lignin, callose, etc.), is considered the main part of the resistance mechanism, because negating of such defense reactions by prior treatment with several metabolic inhibitors or pre-inoculation with compatible fungi allows pathogenic fungi to invade non-host plants. Barriers induced in plant tissues after fungal invasion seem to block penetration, growth, and reproduction of the pathogen. Resistance-inducing substances called inducers or elicitors are released from spores into spore-germination fluid of both pathogenic and nonpathogenic fungi (Hayami et al., 1982; Shiraishi et al., 1978b). As far as the authors know, there is no pathogen that does not produce elicitors. Elicitors from pathogenic fungi are also able to induce resistance in their host.
KeywordsPhytophthora Infestans Alternaria Alternata Plasma Membrane ATPase Fungal Pathogenesis Nonpathogenic Fungus
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