THE STRUCTURE OF THE YIELD OF CORN HYBRIDS DEPENDING ON THE APPLICATION OF MACRO- AND MICROFERTILIZERS DURING THE MILKY-WAXY RIPENESS OF THE GRAIN

The cultivation of corn occupies a leading position in modern agriculture, requiring constant improvement of technological elements to realize the genetic potential of hybrids. One of the key factors influencing the formation of high productivity is the optimization of mineral nutrition, specifically the balanced application of macro- and microfertilizers. This article presents the results of research aimed at determining the effect of different doses of mineral fertilizers and foliar application of microfertilizers on the formation of the yield structure of corn hybrids during the grain filling period, specifically the milk and milky-waxy ripeness stages. The research was conducted during 2022 and involved a comparative analysis of four corn hybrids with different FAO maturity groups: Amaros (FAO 230), Bogatyr (FAO 290), KWS 381 (FAO 350), and Carifols (FAO 380). The experiment scheme included variants without fertilizers (control), as well as the application of mineral fertilizers at doses of N90Р60К60 and N120Р90К90. Additionally, the efficiency of microfertilizer systems was studied, including seed treatment with YaraVita Teprosyn NP+Zn combined with spraying in the 3–5 leaf phase with YaraVita Maize Boost, and seed treatment with YaraTera Tenso Cocktail combined with spraying with YaraVita Kombiphos. The structure of the harvest was determined by taking plant samples to analyze the ratio of the weight of leaves, stems, wrappers with cob cores, and grain. The analysis of the obtained data revealed a significant dependence of the formation of vegetative and generative organs on the level of mineral nutrition. It was established that the increase in the dose of mineral fertilizers to N120Р90К90 provided the highest indicators of the weight of the whole plant and its individual elements across all studied hybrids. For example, in the mid-season hybrid KWS 381, the weight of the whole plant increased significantly in the variant with maximum fertilization compared to the control. The application of microfertilizers also had a positive effect on the formation of the yield structure. The variant involving seed treatment with YaraTera Tenso Cocktail and foliar application of YaraVita Kombiphos proved to be the most effective, ensuring the maximum accumulation of biomass. The results of the study also highlighted the biological features of the hybrids. Late-maturing hybrids, such as Carifols, formed a larger vegetative mass and grain weight compared to early-maturing hybrids under identical nutrition conditions. The research confirms that the integrated use of macrofertilizers in the dose of N120Р90К90 and modern microfertilizer systems allows for maximizing the structural elements of the corn yield. These findings substantiate the feasibility of using intensive mineral nutrition systems to increase the productivity of corn hybrids in the conditions of the research area.