Mechanisms of Salt Tolerance in Brassica napus, Soybean and Chenopodium quinoa: Implications for Sustainable Agriculture in Saline-Alkali Soils

Abstract

This study investigated the physiological responses of three salt-tolerant crops (Brassica napus, soybean, and Chenopodium quinoa) to varying salt stress levels (control, mild, moderate, severe) under controlled conditions. Experimental data revealed a pronounced suppression of both germination and early seedling development in all tested species when exposed to saline conditions, with Chenopodium quinoa exhibiting superior tolerance, maintaining higher germination rates and biomass under severe stress. Physiological analyses revealed elevated malondialdehyde (MDA) content, indicating oxidative damage, alongside increased proline and soluble protein levels for osmotic adjustment. Chenopodium quinoa uniquely upregulated catalase (CAT) and ascorbate peroxidase (APX) activities under high stress, suggesting enhanced antioxidant capacity. These findings highlight Chenopodium quinoa’s potential for saline-alkali land restoration and sustainable crop production under climate change. The study provides critical insights for breeding salt-tolerant varieties and optimizing agricultural practices in marginal ecosystems.