Mitigation of Salinity Stress Effects on Broad Bean Productivity Using Calcium Phosphate Nanoparticles Application

Abstract

Water salinity is one of the major abiotic stresses, and the use of saline water for the agricultural sector will incur greater demand in the coming decades. Recently, nanoparticles (NPs) have been used for developing numerous plant fertilizers as a smart and powerful form of material with dual action that can alleviate the adverse effects of salinity and provide the plant with more efficient nutrient forms. This study evaluated the influence of calcium phosphate NPs (CaP-NPs) as a soil fertilizer application on the production and bioactive compounds of broad bean plants under salinity stress. Results showed that salinity had deleterious effects on plant yield with 55.9% reduction compared to control. On the other hand, CaP-NPs dramatically improved plant yield by 30% compared to conventional fertilizer under salinity stress. This improvement could be attributed to significantly higher enhancement in total soluble sugars, antioxidant enzymes, proline content, and total phenolics recorded use of nano-fertilizer compared to conventional use under salt stress. Additionally, nano-fertilizer reflected better mitigatory effects on plant growth parameters, photosynthetic pigments, and oxidative stress indicators (MDA and H2O2). Therefore, our results support the replacement of traditional fertilizers comprising Ca2+ or P with CaP-nano-fertilizers for higher plant productivity and sustainability under salt stress.

Salt Priming as a Smart Approach to Mitigate Salt Stress in Faba Bean (Vicia faba L.)

“…The present study reflected a boost in POX, CAT, GR, APX, and SOD activities in response to salt stress. In accordance with these results, Nasrallah et al [44] documented the positive correlation between salt stress and the activities of POX, CAT, and SOD. The enhancements in these enzymes' activities following exposure to 120 and 150 mM of NaCl were also assayed in pearl millet [61].…”

“…As a defense, our results mirrored a corresponding increase in the addressed enzymatic antioxidant activities. The correlation between the increase in H 2 O 2 content and the enhanced activities of antioxidant enzymes was also documented by several research groups [44,47,64]. The enhancement of enzymatic antioxidant activities following priming was also recorded for SOD in salt-primed cucumber plants [65] and for SOD, as well as CAT, in Zea mays [66].…”

“…They prevent free radicals from diffusing into the membrane's hydrophobic matrix and/or restricting oxidative stress-induced reactions in the bilayer's hydrophobic region [73]. The increase in phenolics in response to salt stress was also recorded in faba bean [44], wheat [74], and rapeseed [75].…”

“…Nasrallah et al [44] recorded the building up of H 2 O 2 and MDA, accompanied by growth retardation and a decrease in pigments of faba bean foliage leaves, as a consequence of salinity stress. The same observations were recorded by Ahmad et al [18] in pea exposed to salt stress.…”

“…In addition to acting as an accessory pigment, carotenoids exhibit antioxidant properties; the enhanced carotenoids/chlorophyll ratio is a mechanism for avoiding photo-oxidation [53]. Under salt stress, an elevated carotenoids/chlorophyll ratio was recorded in sugarcane [54], Leptochloa fusca [53], maize [55], and faba bean [44].…”