Adaptation strategies of Moringa oleifera under drought and salinity stresses
Abstract
S. Bekka*, K. Tayeb-Hammani, I. Boucekkine, M.Y. El-Amin Aissiou and Z.E. Djazouli
The search for a better adaptation to environmental variation has become prominent to yield stabilization. Indeed, the key points in the environmental variation are due to the sensitivity of plants to different biotic and abiotic stresses that characterize the environmental production. Moringa oleifera is a medicinal plant recognized for its wide use in the fields of agronomy, phytotherapy and nutrition. To achieve that, the objective of this study is to investigate the effect of abiotic stress on the physiological responses of M. oleifera plants subjected to different types of stresses, namely drought stress for 20 days and a different concentrations of NaCl (5 and 10 g/L). Different constraints were applied to test the influence of environmental factors on plant growth, relative water content (RWC), Total non-enzymatic antioxidant capacity (TAC), photosynthetic pigment content, endogenous free proline and phenolic compounds. Plants subjected to different stress conditions were compared with control. However, there is a considerable variation among the plants studied in response to different types of abiotic stresses. In this study, we found that abiotic stress induces a series of morphological disturbances in M. oleifera plants, resulting in reduced growth and RWC. Also there was presence of significant reduction in carotenoid levels. However, the adaptive responses of M. oleifera to various stresses have been observed by a strong accumulation of endogenous proline and an increase in total polyphenol content and radical scavenging activity (RAS). These results could be useful for evaluation of the degree of adaptation of plant growth under environmental constraints.