YIELD OF GREEN MASS OF CORN HYBRIDS DEPENDING ON THE APPLICATION OF MACRO- AND MICROFERTILIZERS IN THE WAXY RIPENESS STAGE OF THE GRAIN

Growing corn for green mass requires a comprehensive understanding of the interaction between plant genotype, climatic conditions, and nutrition systems. Optimizing these components is critical for unlocking maximum yield potential and ensuring stable forage production. A detailed study was conducted during 2021-2023 to evaluate the impact of different mineral macrofertilizer rates and microfertilizer application schemes on the green mass yield of mid-early and mid-season corn hybrids at both the milk and waxy ripeness stages. The field experiment investigated mid-early hybrids, specifically Amaros and Bogatyr, alongside mid-season hybrids KWS 381 and Carifols. The evaluated nutritional variants included an unfertilized control, the application of N90P60K60 and N120P90K90, and two targeted micro-nutrition schemes. The first scheme involved seed treatment with YaraVita Teprosyn NP+Zn combined with foliar feeding with YaraVita Maize Boost, while the second utilized seed treatment with YaraTera Tenso Cocktail combined with foliar feeding with YaraVita Kombiphos. The analysis of the obtained data indicates a significant dependence of crop productivity on the hydrothermal conditions of the growing years. The least favorable conditions for biomass accumulation occurred in 2021, resulting in the lowest baseline yields across the unfertilized control variants for both harvesting stages. Conversely, the weather conditions in 2022 were the most optimal, allowing the plants to achieve the highest productivity indicators. Intermediate results were recorded during the 2023 growing season. Regarding the genetic potential of the studied crops, the mid-season hybrids KWS 381 and Carifols consistently formed a higher green mass yield compared to the mid-early Amaros and Bogatyr hybrids, regardless of whether the harvest occurred at the milk or waxy ripeness stage. Mineral nutrition acted as the primary driver for increasing productivity. The application of macrofertilizers, particularly at the maximum dose of N120P90K90, provided the most substantial increase in green mass for all studied hybrids. The supplementary application of microfertilizers guaranteed an additional and stable yield increase across all mineral nutrition backgrounds. Both studied microfertilizer schemes contributed equally well to enhancing the overall productivity of the corn plants. The absolute maximum yield indicators throughout the entire three-year experiment were achieved in the highly favorable 2022 season by the mid-season Carifols hybrid. Under a complex combination of the maximum macrofertilizer dose N120P90K90 and the YaraTera Tenso Cocktail and YaraVita Kombiphos microfertilizers, this hybrid yielded 54.1 t/ha at the milk ripeness stage and 54.0 t/ha at the waxy ripeness stage. Ultimately, a balanced and intensive combination of macro- and micro-nutrition allows for the maximum realization of the productive potential of modern corn hybrids, although the final volume of green mass yield remains largely modulated by the specific hydrothermal conditions of the growing year.