Impact of Glycine Betaine on Drought Tolerance of Moringa oleifera Plant Grown under Sandy Soil

摘要

Background and Objective: Glycine Betaine (GB) is one of the best powerful compatible solutes that save plants from abiotic stresses like drought. External treatment of GB is well known to regulate a myriad of physiological and biochemical processes in plants subjected to stress like drought. This research attempted to evaluate the effect of external treatment of Glycine Betaine (GB) on growth, photosynthetic pigments, endogenous Indole Acetic Acid (IAA), some osmoprotectants, yield quantity and quality, in the favour of total carbohydrates, proteins and antioxidant compounds in the yielded plants grown under normal as well as under drought-stressed conditions. Materials and Methods: A field experiment was carried out during two successive seasons in the Experimental Station of National Research Centre, Nubaria district, Beheira Governorate, Egypt. Moringa oleifera plants were treated with Glycine Betaine (GB) (10, 20 and 30 mM). Results: Water deficit significantly decreased Moringa oleifera growth and yield quantity and quality through decreasing photosynthetic pigments and IAA, accompanied by significant increases in some osmoprotectants and phenolics contents. Meanwhile, Different GB concentrations enhanced growth parameters and yield and its components via enhancing photosynthetic pigments, IAA, proline, TSS and free amino acids in Moringa oleifera plants under normal or drought stress conditions. In general, 20 mM GB was the most effective treatment in ameliorating the reduced effect of drought stress on Moringa oleifera plants. Conclusion: Finally, it can conclude that using different concentrations of GB as foliar treatment not only improved the growth and yield of Moringa oleifera plants under normal irrigation conditions but also, could ameliorate the decreased effect of drought on Moringa oleifera plants.