Assessing the Impact of Simulated Water and Salinity Stress on the Physiological and Biochemical Characteristics of [Bacopa monnieri (L.) Wettst.]

Abstract

Introduction: The growth, development, and biosynthesis of secondary metabolites in the plant are strongly affected by environmental stress. The pharmaceutical values of medicinal herbs depend on the presence of secondary metabolites that are influenced by environmental stress. Drought and salinity stress are the two most significant abiotic factors that restrict plant growth and productivity.  As a memory enhancer, anti-inflammatory, analgesic, antipyretic, sedative, and antiepileptic, Bacopa monnieri has been used for a long time. The aim of the present work was to study the impact of simulated abiotic stress on Bacopa monnieri. Methodology: Potted plants of Bacopa monnieri were treated with various concentrations of NaCl and polyethylene glycol (PEG) solution to simulate salinity and drought stress. In order to evaluate the salinity and drought stress effect, several physiological parameters, such as cell membrane stability and relative water content (RWC), and biochemical parameters, such as proline, β-carotene, MDA, total phenolic, and total flavonoid content, were taken into consideration. Results: In the present study, significant changes in the physiological and biochemical parameters have been observed in NaCl and PEG 6000-induced salt- and drought-stressed plants about control. Stress decreases the relative RWC and Membrane stability index of the Bacopa leaves. However, it increases the plant’s proline, β-carotene, phenolic compounds, and total flavonoids content. Conclusion: The data obtained from the current study indicated that both salinity and drought stress influence the physiological and biochemical traits of Bacopa monnieri L. By increasing the synthesis of proline, β-carotene, phenolic compounds, and total flavonoids, the Bacopa monnieri plant defends itself against oxidative stress.