Silicon-based adaptive approaches to enhance cotton (Gossypium hirsutum L.) resilience under salinity stress
Abstract
Abstract Background Cotton ( Gossypium hirsutum L.) production in arid and saline soils is severely constrained by multiple abiotic and biotic stresses. To enhance stress resilience, this study evaluated the physiological and biochemical effects of three preparations, Aminosid-Aton, Bionitrogen, and the silicon-based Aminosid-Silicon, on a cotton variety, Bukhara-8, grown under salinity stress. Results Under laboratory conditions, all preparations enhanced early seedling vigor compared with the untreated control, with Aminosid-Silicon producing the strongest response, resulting in an approximately 2.50-fold increase in shoot height and a 2.70-fold increase in root length. Under saline field conditions, seed germination increased from 78.30% in the control to 88.80%, 93.10%, and 96.30% in the Aminosid-Aton, Bionitrogen, and Aminosid-Silicon treatments, respectively, representing increases of 10.5, 14.8, and 18.0 points. Antioxidant enzyme activities were significantly enhanced by all preparations. Compared with the control, peroxidase, catalase, and phenylalanine ammonia-lyase activities increased by up to 12.60%, 26.20%, and 82.50%, respectively, with the highest values consistently observed in Aminosid-Silicon-treated seedlings. Flavonoid and proline accumulation increased under all treatments, with the highest values recorded under the Aminosid-Silicon treatment, where flavonoid and proline contents increased by 15.40% and 28.80%, respectively, compared with the control. Silicon application strongly stimulated superoxide dismutase activity in cotton integuments at early developmental stages. Superoxide dismutase activity increased by 14.80% at 20 days after the treatment and reached a maximum of 86.13 U·mg −1 protein at 30 days after the treatment, representing a 10.00% increase over the control. This early enhancement of antioxidant activity was associated with fiber initiation occurring approximately 10 days earlier than in untreated plants. In addition, the silicon-based treatment significantly improved fiber quality parameters, including the spinning consistency index (+8 units), upper half mean length (+1.7 mm), and fiber strength (+2.3 cN·tex⁻ 1 ), while reducing the short fiber index. The application of preparations, particularly Aminosid-Silicon, significantly reduced pest infestation, with total infestation declining from 22.4% in the control to 11.7%. Under saline and arid field conditions, seed cotton yield increased from 3 830 to 4 620 kg·hm −2 in the control to 4 620 kg·hm −2 in Aminosid-Silicon-treated plots, representing a 20.6% improvement. Conclusions Among the tested preparations, Aminosid-Silicon demonstrated the greatest efficacy in enhancing early seedling development, antioxidant defense capacity, non-enzymatic metabolite accumulation, fiber quality, pest resistance, and yield under stress conditions. These findings highlight the potential of silicon-based preparations as an effective and environmentally sustainable strategy for improving cotton productivity in saline and arid environments.