Impact of Foliar Application of Zinc Sulphate with Nitrogen Fertilizer on Morphological Responses and Yield Improvement of Winter Wheat (Triticum aestivum L.)
摘要
This study investigates the synergistic effects of zinc sulfate (ZnSO₄ · 7 H₂O) foliar application combined with varied nitrogen levels on wheat growth, zinc accumulation, and grain quality. A field experiment was conducted employing three nitrogen application rates (0, 180, and 240 kg ha−1) and four zinc sulfate concentrations (0, 0.16%, 0.32%, and 0.48%) applied at the flowering stage. Results demonstrated that the highest nitrogen level (240 kg ha−1) coupled with 0.32% zinc significantly enhanced dry matter accumulation at maturity by 5–30%, increased grain zinc transport rate by 33–37%, and doubled grain zinc content. Additionally, this treatment improved spike number per plant and 1000-grain weight by 30–35% and 20–26%, respectively, leading to a yield increase of 12–18%. Nutritional quality was markedly improved, with total protein content rising by 30–45% across growing seasons compared to lower nitrogen application. The combined application also increased zinc utilization efficiency by 50–64%, elevated nitrogen accumulation by 15–29%, and optimized nitrogen transfer processes before and after flowering, thereby supporting grain development. These findings underscore the importance of integrated nutrient management and biofortification strategies, demonstrating that foliar zinc application alongside optimal nitrogen fertilization can substantially improve wheat yield, grain zinc content, and nutritional quality, contributing to enhanced crop productivity and dietary zinc intake