FACTORS OF AGRICULTURE AND REGULATION OF GROWTH RESPONSE IN AGRICULTURAL CROPS

Under the conditions of climate change and the need to preserve soil fertility, an important aspect of modern agriculture is the search for effective primary tillage techniques. The optimisation of maize cultivation technologies in the Northern Steppe of Ukraine has a significant impact on crop productivity and the ecological sustainability of agroecosystems. The aim of this study was to determine the effect of different primary tillage methods on growth processes and maize grain yield. The research was conducted during 2019–2021 on ordinary chernozem with a humus content of 4.2% and an annual precipitation level of 495 mm. The experiment included four primary tillage treatments: ploughing (23–25 cm), chisel tillage (25–27 cm), disc harrowing (10–12 cm), and No-till. Herbicide application, weed control, biometric measurements of maize plants, and grain yield determination were carried out in accordance with standard methodologies. It was established that the tillage system significantly influenced yield parameters. The highest maize yield (6.99 t/ha) was obtained after ploughing, while chisel tillage provided 6.62 t/ha, disc harrowing – 6.27 t/ha, and No-till – 6.11 t/ha. Reducing tillage depth decreased field emergence by 3.3–7.8% compared to ploughing. Herbicide application reduced weed density by 58–91%. It was found that minimal and zero tillage promoted the accumulation of crop residues in the upper soil layer (up to 97%), which influenced the thermal regime and slowed crop emergence. Ploughing was identified as the optimal primary tillage method for maize cultivation in the region, ensuring the highest yield as well as uniform plant growth and development. Minimal and zero tillage contributed to the accumulation of organic residues in the upper soil layer, which positively affected erosion resistance but reduced seedling emergence and yield. The obtained results can be used for developing adaptive farming systems under the conditions of the Northern Steppe of Ukraine.