Improving drought tolerance of moringa plants by using trehalose foliar treatments

A field experiments was conducted during two seasons (2015/2016 and 2016/2017) at the Experimental Station of National Research Centre, Nubaria district, Beheira Governorate, Egypt, to investigate the role of external treatments of moringa plant with trehalose (Tre) (12.5, 25 and 50 mM) on growth, photosynthetic pigments, indole acetic acid (IAA), phenolics, some osmolytes (total soluble sugars TSS, free amino acids and proline), and yield quantity and quality such as nutritional and antioxidant compounds in the yielded plants which subjected to water deficiency (drought stress). Drought stress decreased markedly growth criteria of moringa plant (shoot height, number of leaves, fresh and dry weights of leaves, shoots & total plant), photosynthetic pigments and endogenous IAA with marked increases in phenolic, TSS, free amino acids and proline contents. In addition to decreased yield and yield components, protein%, carbohydrates%, Nitrogen%, phosphorous%, potassium%, calcium% and magnesium%, as well as antioxidant activity of the yielded plants. Meanwhile, flavonoids content increased by escaping irrigation. Whereas, Tre treatments was effective in improving growth criteria and the studied biochemical parameters of plants grown under drought stress.. Moreover, Tre external increased markedly yield and yield components, protein, carbohydrate, nitrogen, phosphorous, potassium, calcium and magnesium percentages and flavonoids contents as well as antioxidant activity of the yielded plants either in non stressed and drought stressed plants relative to their corresponding controls. 25 mM Tre was the most effective concentration in ameliorating the adverse effect of drought stress on moringa plants.