Hormone regulatory pathway of SALICYLIC ACID (SA)
SALICYLIC ACID (SA) Salicylic acid (SA) is a secondary metabolite produced by a wide range of prokaryotic and eukaryotic organisms including plants. Chemically, it belongs to a group of phenolic compounds defined as substances that possess an aromatic ring bearing hydroxyl group or its functional derivative. Long before SA’s regulatory role in multiple physiological processes of plants attracted people’s attention, the pharmacological properties of salicylates (general name of SA and its derivatives) had been prized. Salicylates have been known to possess medicinal properties since the 5th century B.C., when Hippocrates prescribed salicylate-rich willow leaf and bark for pain relief during childbirth (Rainsford 1984; Weissman 1991). However, the utilization of salicylate-containing plants for curing aches and fevers can be traced back to inhabitants of both the Old and New Worlds. In 1828, German scientist Johann A. Buchner purified a small quantity of the yellowish substance named sali...