Enhancing maize productivity under abiotic stresses through the combined use of nitrogen, potassium humate, and zinc

The soils found in the Kharga oasis in Egypt have been identified as having low levels of nitrogen and organic matter, along with high pH and salinity. These conditions make it difficult for the plants to absorb essential micronutrients. In order to address this issue, a study was conducted with the main objective of evaluating the interactive effect of potassium humate, zinc, and nitrogen fertilization on the grain yield of maize and its various components. The study consisted of two field experiments that took place during the growing seasons of 2022 and 2023 at the research station of the Desert Research Center in Kharga, located in the western desert of Egypt. The treatments in the experiments involved three different levels of potassium humate and zinc combinations, including 20 kg/ha of potassium humate, 375 ppm of zinc, and a combination of both, which were compared to a control group. Additionally, four levels of nitrogen fertilization were applied, ranging from 100 to 400 kg/ha. The results of the study revealed that the highest and most significant grain yields were observed in both seasons when potassium humate and zinc were applied together, resulting in yields of 10,436 and 10,590 kg/ha in the first and second seasons, respectively. Furthermore, it was found that the highest significant grain yields in both seasons were achieved by applying 300 kg of nitrogen per hectare, with yields of 9423 and 9196 kg/ha in the first and second seasons, respectively. These findings suggest that the combination of nitrogen fertilization with potassium humate and zinc proves to be effective in maximizing the grain yield of maize. This information is valuable for farmers and researchers in the Kharga oasis, as it provides insights into the optimal fertilization practices that can enhance crop productivity in this specific region with challenging soil conditions.