Defense Traits and Tolerance Strategies of Plants against Herbivores

Abstract

Plants exposes to various types of biotic and abiotic stresses. It received various signals called Herbivore-associated molecular patterns (HAMPs) and induces defence mechanism against insects. Defense system, by this plant mitigates the adverse effects of herbivore, consisting of various morphological, biochemical, and molecular mechanisms. The trichomes, epidermis, cuticle, and bark tissues are important physical barriers to herbivores. Various secondary metabolites reduces digestibility in insect. The cysteine protease overexpression in maize retard the growth of S. frugiperda. In Arabidopsis, release of green-leaf volatiles by overexpression of hpl gene increases, which increases attraction of parasitoid Cotesia glomerata that increases mortality of larva of Pieris rapae. The application of plant hormones like JA, SA, and Ethylene etc. also induces defence system in the plant against insect. However, the exact defensive mechanism is still not understood. Studying the level of molecular mechanism of induced resistance against insect could be an important tool for the pest management.