ZINC FERTILIZATION STRATEGIES FOR SUSTAINABLE MAIZE PRODUCTION: CURRENT TRENDS AND INSIGHTS

Abstract

Zinc (Zn) is an essential micronutrient that plays a vital role in maize (Zea mays L.) growth, development, and productivity. However, zinc deficiency has emerged as a widespread constraint to maize production, particularly in intensively cultivated and calcareous soils, due to continuous nutrient mining, imbalanced fertilization, and declining soil organic matter. Inadequate zinc availability adversely affects key physiological processes including enzyme activation, protein synthesis, hormone regulation, photosynthesis, pollen viability, and grain formation, leading to substantial yield losses and poor grain nutritional quality. This review synthesizes current knowledge on zinc nutrition in maize, emphasizing the physiological functions of zinc, soil factors governing its availability, and the global extent of zinc deficiency in agricultural soils. Conventional zinc fertilization approaches such as soil application, foliar sprays, and seed treatments are discussed alongside emerging strategies including nano-zinc formulations, slow-release fertilizers, and organomineral zinc complexes designed to enhance zinc use efficiency and minimize environmental losses. The role of integrated soil fertility management practices combining zinc fertilization with organic amendments and balanced nutrient inputs is critically examined for their synergistic effects on maize yield, grain zinc concentration, and soil health. Furthermore, the review highlights key challenges associated with zinc management under varying soil conditions and outlines future research directions focusing on long-term sustainability, field-scale evaluation of advanced zinc fertilizers, and socio-economic feasibility for smallholder farming systems. Overall, effective zinc fertilization strategies are essential for improving maize productivity, nutritional quality, and sustainability of agro-ecosystems, contributing to both food security and micronutrient enrichment.