Green-Synthesized Zinc Oxide Nanobiofertilizers: Effect on Zea mays Germination and Initial Growth in Mine Soils, Cesar, Colombia

The degradation of agricultural soils and the low efficiency of conventional fertilizers pose significant challenges to sustainable agricultural production. In this context, nanobiofertilizers have emerged as a promising alternative for increasing nutrient availability and improving early plant development. This study evaluated the effect of a zinc oxide nanobiofertilizer (NBF-ZnO) synthesized via a green route using Mangifera indica leaf extract on the germination and early growth of maize (Zea mays L.) seedlings. The synthesized nanoparticles were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), and UV-Vis spectroscopy to confirm their structural and optical properties. Subsequently, germination and early growth trials were conducted under four treatments: control, mango extract, conventional fertilizer (Triple 15), and NBF-ZnO, using soil affected by mining activities in the department of Cesar (Colombia). The results showed that the NBF-ZnO treatment achieved the highest germination (93%) and seedling growth (92.5%), outperforming the conventional fertilizer and the other treatments. Statistical analysis using the chi-square test confirmed significant differences between treatments (α = 0.05). These findings suggest that ZnO nanobiofertilizers obtained through green synthesis could represent a promising strategy for enhancing early maize development and contributing to the sustainable management of soils affected by mining activity.