Role of osmolytes in improving water deficit stress tolerance in Echinacea purpurea an important Himalayan medicinal plant

Abstract

newline ABSTRACT newlineWater-deficit stress is one of the prime abiotic stresses in the world including salinity, drought, heat/ cold, light and other hostile conditions leads to the production of reactive oxygen species (ROS). ROS stimulates active signaling compounds capable of triggering production of bioactive compounds (secondary metabolites) that enhances the medicinal value of the plant. Echinacea purpurea L., a medicinal plant, was selected in the present study. The plant was subjected to abiotic stress, namely, water-deficit (1%, 2.5%, 5%, 7.5% and 10% PEG) and osmolytes proline and glycinebetaine (50ppm and 100ppm) in order to see their impact on morphological, physiological, biochemical parameters on E. purpurea. The study revealed that water-deficit stress causes a significant decrease in seed germination, shoot length, root length, plant height and fresh weight under all the concentration of PEG treatments. Osmolytes play a significant role to increases relative water content in the lower concentrations but showed a decrease in higher concentration. Constitutive activities of CAT, POD, MDA, and total phenol showed an enhancement due to stress and osmolytes studied. Overall results showed that the osmolytes play a significant role on physiological and biochemical consequences of E.purpurea under water-deficit stress.