Host Defense Mechanisms During Fungal Pathogenesis and how these are Overcome in Susceptible Plants: A Review

The interaction between plants and fungal pathogens comprises a range of mechanisms that determine the outcome of the interaction, i.e., compatible leading to susceptibility or incompatible leading to resistance. Several host defense mechanisms act both in susceptible and resistant plants. Yet, in the case of a compatible interaction involving a susceptible host and a virulent pathogen, the latter is able to win the battle and cause disease. By documenting several interactions between plant and fungal pathogens, this review describes some of the mechanisms which plants use for defense such as the reinforcement of the cell wall and the accumulation of pathogenesis-related (PR) proteins and of secondary metabolites and ways by which pathogens overcome plant defense.