Evaluation of four medicinal herb species under conditions of water-deficit stress

Abstract

Abilities of four commercial herb species namely, Chlorophytum borivilianum, Stevia rebaudiana, Withania somnifera, and Andrographis paniculata were tested for relative drought tolerance under poly house conditions. The findings based on the quantum of data collected for growth, yield of economic parts and physiological traits reveal differential relative potential to sustain performance and cope with the conditions of water stress. Comparative performance of four herb species under stress (50% water deficit) for stress duration of 10, 20 and 30 days revealed significant adverse effects of water-deficit stress as well as stress durations. Out of the four herb species studied, adverse impact of 50% water deficit up to 30 days of stress on growth, yield, rate of photosynthesis, canopy temperature depression and chlorophyll fluorescence (Fv/Fm) ratio was significantly higher in S. rebaudiana and A. paniculata in comparison to C. borivilianum and W. somnifera. In this study, C. borivilianum and W. somnifera have exhibited greater relative drought tolerance as compared to A. paniculata and S. rebaudiana.