Ferrous sulfide-sepiolite clay nanocomposite (FSp-NC) efficiently modulated the physiological parameters of soybean (Glycine max) seedlings with augmented iron assimilation and antioxidative responses
摘要
Nanocomposite-based seed priming has emerged as a promising strategy to enhance seed germination, seedling vigor, and stress resilience through improved nutrient bioavailability and uptake efficiency. In the present study, a ferrous sulfide-sepiolite nanocomposite (FSp-NC) was synthesized via an in situ ultrasonic-assisted method and evaluated for its potential as an efficient nanopriming agent for soybean (Glycine max L., variety SL-958). The effects of FSp-NC priming were compared with conventional FeSO4 treatment in terms of germination performance, early growth traits, and iron assimilation. Among the tested concentrations, FSp-NC at 250 µg/g for 6 h resulted in the highest enhancement in germination percentage (93.11 ± 1.116%), shoot length (19.02 ± 1.124 cm), root length (12.65 ± 0.308 cm), seedling fresh weight (1.98 ± 0.011 g), dry weight (0.99 ± 0.004 g), and vigor index (93.75 ± 0.085). The optimized treatment significantly increased Fe content in shoots (91.36 ± 1.162 mg/ kg) and roots (68.34 ± 2.513 mg/kg) compared to FeSO4 primed seeds, confirming superior iron bioavailability and translocation. Furthermore, total phenolic content and total flavonoid content were markedly elevated, accompanied by enhanced activities of key antioxidant enzymes, including superoxide dismutase, catalase, ascorbate peroxidase, and peroxidase, while polyphenol oxidase activity decreased. The free radical scavenging capacity, measured by DPPH and ABTS assays, was also significantly improved in FSp-NC treated seedlings. Thus, FSp-NC nanopriming substantially enhanced germination, iron assimilation, and antioxidant defense in soybean, establishing it as a sustainable and superior alternative to conventional FeSO4-based priming for improved seedling performance and crop establishment.