Salicylic Acid: A Plant Defense Hormone
Keywords:
Plant hormone, Immune system, Disease resistance, Insect defense, Environmental stressAbstract
Salicylic acid (SA) is a crucial plant hormone that acts as the master regulator of the innate immune system. Because plants lack specialized immune cells, they rely on SA to trigger localized programmed cell death and activate antimicrobial proteins to trap and neutralize invading pathogens and defend against insects by altering defensive metabolites and recruiting natural predators. Beyond insect and disease resistance, SA helps plants tolerate severe environmental stresses like drought and salinity. While SA offers immense potential for sustainable agriculture, researchers are developing advanced nano-formulations to overcome its natural phytotoxicity and ensure safe, controlled crop protection.
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