Plant–Fungus Interaction: A Stimulus–Response Theory

Plants are exposed to various severe constraints comprising damages caused by phytopathogens, which eventually lowers productivity. During plant–fungus interaction, the fungus absorbs host nutrients by secreting cell wall-degrading enzymes, toxins, suppressing plant defense, triggering programmed cell death, and shutting down plant defensive genes. Plants have various defense mechanisms to counteract the harmful effects of fungi including constitutive and induced defense systems that either directly or indirectly attack the fungus. However, throughout co-evolution, both pathogens and plants have acquired their combat systems at the molecular level in a see-saw fashion and this tug-of-war between them has evolved endlessly. Hence, we are still a long way from fully comprehending all the variables determining the winner of this arms race. Therefore, the present review will help to broaden our knowledge about the events occurring during plant–fungus interaction, unfolding a process of unexpected complexity.