Sargassum wightii Aqueous Extract Improved Salt Stress Tolerance in Abelmoschus esculentus by Mediating Metabolic and Ionic Rebalance

Abstract

Salinity stress has hindered the growth and yield of crops globally. The demands for inducing salt stress tolerance by natural and biological sources with potent antioxidants and growth-promoting metabolites have been the main focus of the recent era. Therefore, the current research was conducted to extract salt stress tolerance-ameliorating metabolites and growth-promoting hormones from the marine brown macroalgae Sargassum wightii Greville ex J. Agardh with maximum antioxidant potential used as a liquid fertilizer for okra (Abelmoschus esculentus L.). In the current study, the biochemical analysis showed that Sargassum aqueous extract (SAE) was rich in growth-promoting metabolites, antioxidants, and hormones. Meanwhile, overaccumulation of glycine betaine attracted the focus of the current research dealing with salt stress tolerance amelioration in A. esculentus. The plants supplemented with SAE (2% and 4%) and 0.04% ascorbic acid (AsA) alone and in combinations were subjected to sodium salt stress (NaCl; 75 mM). Results revealed that SAE efficiently promoted the vegetative and reproductive growth of plants by elevating the growth-promoting metabolites and hormones in comparison to control plants. Ionic contents (Na+, K+, Ca2+, and Mg2+) and ratios (K+/Na+, Mg2+/Na+, and Ca2+/Na+) were modulated in SAE-treated plants. SAE also increased the level of carbohydrates, proteins, lipids, carotenoids, and proline and decreased the level of hydrogen peroxide and abscisic acid in salt-treated plants compared with the control groups. Enzymatic activities of catalase, ascorbate peroxidase, and guaiacol peroxidase were also enhanced by SAE treatment upon salt stress. The SAE-mediated stress tolerance amelioration and the positive growth response of A. esculentus were further accelerated by AsA (0.04%) supplementation used in combination with SAE (2% and 4%). The current study revealed a novel report of the antioxidant and metabolite-rich algal extract (S. wightii) formulation along with AsA that induced salt stress tolerance and promoted the overall growth performance of A. esculentus by rebalancing the ionic and metabolic status.

Endophytic Fungal Consortia Enhance Basal Drought-Tolerance in Moringa oleifera by Upregulating the Antioxidant Enzyme (APX) through Heat Shock Factors

“…Due to drastic climate change, the growth and productivity of some important plants including M. oleifera significantly showed a negative growth impact. However, scientists applied different approaches including synthetic chemicals, nutritional (plant/seaweed extracts), and biological amendments (endophytic and rhizosphere microbes) to ameliorate stresses [ 48 , 49 ]. The application of such approaches is of specific interest in the conception of seedling’s response under drought stress and to gain knowledge for the success of reforestation programs based on woody species such as Pinus Halepensis [ 50 ], and M. oleifera.…”

Construing the resilience to osmotic stress using endophytic fungus in maize (Zea mays L.)

“…In such a range of adverse challenges, innovative techniques and the application of sustainable eco-friendly practices can assist in breaking the feedforward loop by increasing resource use e ciency and promoting healthy crop growth while monitoring hazardous environmental conditions and enhancing soil health (Drost et al 2020). To alleviate stress, researchers used an array of strategies, including endophytic microbes (Aziz et al 2021;Khan et al 2022). The implementation of such an approach is of relevance in conceptualizing plant response to water de cit stress and in gaining knowledge for the success of crop production.…”

Biological synthesis of hybrid silver nanoparticles by Periploca aphylla Dcne. From nanotechnology to biotechnology applications

“…Total antioxidant capacity: TAC was calculated using fresh callus samples (3.0 g) crushed in methanol, as stated by Khan et al (2022) . The sample extract was treated with 3 ml of a solution containing H 2 SO 4 (0.6 mM), sodium phosphate buffer (28 mM), and ammonium molybdate (4 mM).…”