Plants Defense Mechanisms Against Pathogens

Plants have many defense mechanisms against pathogens that can be stimulated and activated by some microorganisms or chemicals. There are five types of induced resistance in plants that are included: localized acquired resistance, systemic acquired resistance, systemic gene silencing, induced systemic resistance, and systemic wounding response. Systemic acquired resistance is the most important type of induced resistance in plants that result in continuous and prolonged protection from infection against a wide range of pathogens. Formation of pathogenesis related proteins, alteration of cell wall with sedimentation and binding of polysaccharides, proteins, glycol-proteins, phenols, phytotoxins, and ligninification are the stages of occurrence of this type of resistance in plants.