Water consumption of sunflower plants under the influence of cultivation technology elements

Proper management of the water regime of plants helps to increase yields. Insufficient or excessive water supply can negatively affect their growth and development, reducing final productivity. The purpose of the study was to identify the influence of weather conditions, fertiliser conditions, and the effect of a retardant on the productivity of sunflower hybrids. Field studies were conducted in 2021-2023 on typical low-humus chernozems. Studies have established that the decisive factor determining the level of yield and water consumption is the amount of soil moisture in 0-100 cm of the soil layer for the sowing period and the amount of precipitation for the general growing season. Total water consumption varied over the years of research: it was the lowest in 2022 and amounted to 2,533 m3/ha, and the largest – in 2023 – 3,645 m3/ha. On average, over three years of research, the total water consumption was 3,095 m3/ ha. The coefficient of water consumption, which characterised the moisture consumption for the development of 1 tonne of seeds with the corresponding amount of by-products, changed under the influence of weather and climatic conditions of the year, morphobiological features of the hybrids that were studied, technological methods, fertiliser optimisation, and in 2021 amounted to 822 to 1,546 m3/t; in 2022 – 716 to 1,299, and in 2023 – from 937 to 1,796 m3/t. The highest water consumption rate per 1 tonne of sunflower seeds was obtained in 2023. In the RGT Wollf hybrid, it changed as fertilisation rates increased from 1,664 to 996 m3/t, Alzan – 1,672-1,108, ES Bella – 1,796-1,187, Lime – 1,727-1,115 m3/t. The use of Setar retardant for sunflower cultivation helped to reduce the coefficient of water consumption and ensured more rational use of moisture by plants for the development of a crop unit. Fertiliser showed the greatest impact on reducing the water consumption coefficient. In the most unfavourable years of cultivation for moisture, the efficiency of using moisture by sunflower plants with nutrition optimisation increased significantly, which indicates the effectiveness of using fertilisers and the Setar retardant. The results obtained will be useful for agricultural enterprises in increasing the efficiency of resource use and improving financial results