Effect of irrigation water quantity and salinity level on growth and internal chemical contents of Moringa plants

Abstract

Moringa 'the miracle tree' is a relatively new promising plant because of its rich nutritional value, viz. mineral nutrients, protein containing all amino acids, vitamins and antioxidants. The objective of this study was to determine the optimal water amount for Moringa productivity even under salinity conditions and to ensure getting better quality and more active substances from it for human nutrition. During the growing seasons of both 2020 and 2021, Moringa seedlings were irrigated with 12 different combinations using three water quantities, i.e. 100, 75 and 50% (of Class A pan evaporation equation) and four salinity levels, i.e. non-saline control, 2000, 3000 and 4000 ppm (NaCl from Rashid salt). The obtained results indicated that decreasing irrigation water quantity from 100 to 50% of pan evaporation negatively affected all vegetative growth characters of Moringa and decreased the contents of essential nutrients, crude protein, vitamin C and total chlorophyll content, albeit the variations between 100 and 75% of pan evaporation sometimes were not significant. On the other hand, increasing salinity levels gradually reduced all vegetative growth characters of Moringa and decreased the essential nutrients, crude protein, vitamin C and total chlorophyll. Notably, Na and proline contents were increased with both decreasing irrigation water quantity and increasing of salinity level.