ABSTRACT
Ascorbic acid (AA) is present in all eukaryotes including animals and plants and lack completely in prokaryotes with exception of cyanobactaria. Today, AA has gained significant place in plant science, mainly due to its properties (antioxidant and cellular reductant etc.), and multifunctional roles in plant growth, development, and regulation of large spectrum of plant defense mechanisms against environmental stresses. Some studies suggests that the endogenous AA has been implicated in the promotion of plant growth and development by involving in a complex array of phytohormonemediated signaling networks that ties together various developmental and environmental stresses. In the last few years, the role of AA in tolerance of plants to environmental stress has established much consideration. As it is evident from the present review, recent progress on AA potentiality in tolerance of plants to environmental stresses has been impressive. Indeed, AA also plays an important role in resistance to developmental programmes (stresses, e.g., bud induction, flowering and senescence) and environmental stresses (e.g., osmotic, temperature, pathogenesis and weedicides and herbicides).