Silicon Nano-Fertilizer-Enhanced Soybean Resilience and Yield Under Drought Stress
Jian Wei, Lu Liu, Zihan Wei, Qiushi Qin, Qiong Bai, Chungang Zhao, Shuheng Zhang, Hongtao Wang
Abstract
Drought stress threatens agriculture and food security, significantly impacting soybean yield and physiology. Despite the documented role of nanosilica (n-SiO2) in enhancing crop resilience, its full growth-cycle effects on soybeans under drought stress remain elusive. This study aimed to evaluate the efficacy of n-SiO2 at a concentration of 100 mg kg−1 in a soil medium for enhancing drought tolerance in soybeans through a full life-cycle assessment in a greenhouse setup. To elucidate the mechanisms of n-SiO2 action, key physiological, biochemical, and yield parameters were systematically measured. The results demonstrated that n-SiO2 significantly increased silicon content in shoots and roots, restored osmotic balance by reducing the Na+/K+ ratio by 40%, and alleviated proline accumulation by 35% compared to the control, thereby mitigating osmotic stress. Enzyme activities related to nitrogen metabolism, including nitrate reductase (NR) and glutamine synthetase (GS), improved by 25–30% under n-SiO2 treatment compared to the control. Additionally, antioxidant activity, including superoxide dismutase (SOD) levels, increased by 15%, while oxidative stress markers such as hydrogen peroxide (H2O2) and malondialdehyde (MDA) decreased by 20–25% compared to the control. Furthermore, yield components were significantly enhanced, with pod number and grain weight increasing by 15% and 20%, respectively, under n-SiO2 treatment compared to untreated plants in drought conditions. These findings suggest that n-SiO2 effectively enhances drought resilience in soybeans by reinforcing physiological and metabolic processes critical for growth and yield. This study underscores the potential of n-SiO2 as a sustainable amendment to support soybean productivity in drought-prone environments, contributing to more resilient agricultural systems amidst increasing climate variability. Future research should focus on conducting large-scale field trials to evaluate the effectiveness and cost-efficiency of n-SiO2 applications under diverse environmental conditions to assess its practical viability in sustainable agriculture.