Abstract:
This study explores the impact of soil salinity on agricultural productivity and investigates the use of ZnO NPs and biochar to alleviate salt stress in saline soils. Unlike gypsum, ZnO NPs offer more plant benefits, providing essential micronutrients and nutrient uptake Biochar outperforms gypsum in improving soil health and water retention and is more sustainable. ZnO nanoparticles were synthesized using Corriandrum sativum extract and characterized using SEM, XRD, and FTIR. The SEM-EDS analysis revealed ZnO NPs have a mesoporous structure and a high surface area, making them highly reactive and suitable for alleviating salt stress. The EDS analysis indicated that NPs consist of 40% zinc, 34% oxygen, and 24% carbon. The XRD analysis confirmed the crystalline structure of the nanoparticles, showing distinct peak planes of ZnO, indicating a hexagonal wurtzite structure and their high crystallinity. The FTIR analysis found characteristic Zn-O bond peaks at 689.32 and 430.14 cm-1, confirming the presence of Zn-O bonds and the formation of ZnO nanoparticles. The plant maize (Zea mays) was used to check the antioxidant response to treatments and examined the effects of treatments with ZnO NPs, BC, and nano biocomposite on soil pH , EC, and nutrient content. Applying ZnO NPs reduced soil pH, from 8.61 to 7.58 in S1 and 9.67 to 7.25 in S2. ZnO NPs + BC treatment, the reduction in EC was significant, from 11.55 to 8.65 dS/m in S2. Nutrient levels also showed positive changes. Nitrogen content increased notably, in the P+NP from 11.83 to 64.66 mg/kg in S1. Potassium increased to 0.109 mg/kg and phosphorus up to 67.6 mg/kg when ZnO NPs applied. Proline, a stress indicator, decreased from 0.55 µmol/g FW to 0.17 in plants treated with ZnO NPs. CAT and POD activities increased significantly, indicating enhanced antioxidant defense. Overall, the research highlights the effectiveness of ZnO NPs, biochar, and composite in improving soil health, increasing nutrient availability, and mitigating salt stress, offering a promising solution for saline soil management
