Calcium Chloride Supplementation Improves in vivo Salt Stress Tolerance of Drumstick (<i>Moringa oleifera</i> L.)

Abstract

Salinity is becoming a bigger problem for agricultural production across the world. Calcium chloride (CaCl2) was used to mitigate the adverse impact of NaCl-induced oxidative stress in terms of growth parameters, chlorophyll, carotenoid, protein, proline, phenolic content (TPC), flavonoid content (TFC), DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate) radical, ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), peroxidase (POD), superoxide dismutase (SOD), glutathione reductase (GR) and catalase (CAT) activity and malondialdehyde (MDA) accumulation in Moringa oleifera L. plants. There were 8 treatments in the experimentation including control, 100 mM NaCl, 200 mM NaCl, 300 mM NaCl, 100 mM NaCl + 3 mM CaCl 2 , 200 mM NaCl + 3 mM CaCl 2 300 mM NaCl + 3 mM CaCl 2 and 3 mM CaCl 2 alone. The results NaCl (100 mM) with 3 mM CaCl 2 revealed that the salt stress inhibited the growth parameters of fresh (7.23±0.2), dry weight (4.03±0.2), number of leaves (13.66±0.6), shoot (17.17±1.0) and root length (19.07±0.7) reduced of M oleifera. While NaCl (100mM) with CaCl 2 (3 mM) treating significantly promoted the growth parameters of M oleifera under salt stress. NaCl (100mM) with CaCl 2 (3 mM) treating plants showed increased carotenoids (0.956±0.03), chlorophyll (1.576±0.04), protein (15.67±0.3), proline (61.66±2.3), TPC (28.20±0.24), TFC, compared with untreated M oleifera under salt stress. NaCl (100 mM) with CaCl 2 (3 mM) treating increased the antioxidant activities (DPPH, ABTS) and antioxidant enzymes activities (POD, SOD, CAT, GR, MDA) compared with untreated M oleifera under salt stress. Therefore, the CaCl 2 can be productively used to enhancement the seedling establishment and growth of M oleifera grown under salt stress conditions. The molecular mechanisms of Ca 2+ signalling induced by CaCl 2 treating in M oleifera under salt stress as seed priming agents on the final yield, even under field conditions should be the focus for future research.