Open Access

ARTICLE

Enhancing Salt Stress Tolerance in Portulaca oleracea L. Using Ascophyllum nodosum Biostimulant

Zahra Alhawsa^*, Rewaa Jalal, Nouf Asiri

Department of Biological Sciences, College of Science, University of Jeddah, Jeddah, 21493, Saudi Arabia

* Corresponding Author: Zahra Alhawsa. Email:

(This article belongs to the Special Issue: Abiotic Stress in Agricultural Crops)

Phyton-International Journal of Experimental Botany 2025, 94(4), 1319-1337. https://doi.org/10.32604/phyton.2025.061918

Received 06 December 2024; Accepted 13 March 2025; Issue published 30 April 2025

Abstract

Salinity stress is a major constraint on agricultural productivity, particularly in arid and semi-arid regions. This study evaluated the potential of Ascophyllum nodosum extract (ANE) in mitigating salinity-induced stress and enhancing the growth and physiological performance of Portulaca oleracea L. under NaCl concentrations of 0, 50, 70, and 100 mM for 50 days. A two-way ANOVA assessed the effects of NaCl concentration, ANE treatment, and their interaction. The results showed that ANE significantly increased plant height at 50 mM NaCl (p = 0.0011) but had no effect at higher salinity levels (p > 0.05). Shoot dry weight was significantly influenced by the interaction of NaCl and ANE (p = 0.0064), with ANE increasing biomass at 0 mM but decreasing it at 100 mM NaCl. However, ANE did not significantly affect root dry weight (p > 0.05). Physiological responses indicated a significant increase in proline content at 50 mM NaCl (p = 0.0011), supporting improved osmotic adjustment. Total soluble protein was significantly enhanced at all salinity levels except 100 mM NaCl (p < 0.01). Regarding ionic regulation, ANE had no significant effect on leaf sap pH (p > 0.05) but increased electrical conductivity (EC) at 70 and 100 mM NaCl (p < 0.01), suggesting a role in ion homeostasis under high salinity. Photosynthetic pigments responded positively to ANE, with significant increases in chlorophyll “a” (p < 0.0001) and carotenoid content (p < 0.0001), while chlorophyll “b” remained unchanged (p > 0.05). These findings highlight ANE’s potential as a sustainable biostimulant for improving salinity tolerance, particularly at moderate NaCl levels. Future research should focus on molecular mechanisms and long-term field applications to optimize ANE’s role in enhancing soil and crop productivity under salinity stress.

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