Влияние приемов возделывания на урожайность и водопотребление подсолнечника в условиях Ростовской области

Abstract

Purpose: to identify the optimal combination of methods for primary tillage, fertilizer background, seeding rates, as well as optimal seeding time that contribute to increasing sunflower yields under edaphoclimatic conditions of the Azov zone Rostov region. The study was completed in 2021–2022 at the experimental station of the scientific center. Materials and methods. The following options were studied: methods of basic tillage (plowing, combined cultivation, chiseling) (factor A); seeding rates (0.055; 0.060; 0.065 million pcs/ha) (factor B); fertilizer backgrounds (high – 80 kg of active substance NPK per 1 ha; medium – 40 kg of active substance NPK per 1 ha; without fertilizers) (factor C). These factors were studied against the background of two seeding dates. The soils are ordinary chernozems. Results. The most favorable conditions for crop vegetation were created under the conditions of the 2nd seeding time. The seed application rate of 0.065 million pcs/ha ensured an oilseed increase in seed yield of up to 36.0–37.1 %. An average fertilizer background increased the yield to 20.7–21.8 %, a high background provided a similar increase to 38.4–40.1 %. The highest return from the fertilizer application was noted with the 2nd seeding time and a rate of 80 kg of active substance NPK per 1 ha with the best average of 2.92 kg/kg. The lowest coefficients of sunflower water consumption were obtained in the variants of the 2nd seeding time, amounting in different years: for plowing 872 and 963 cubic meters/t, combined tillage – 896 and 993 cubic meters/t, chiseling – 906 and 982 cubic meters/t. These indicators turned out to be lower compared to similar data from the 1st seeding time in 2021 by 22.7; 21.5 and 24.5 %, 2022 – by 14.2; 12.8 and 13.8 %. Conclusions. The highest sunflower yield was obtained during the 2nd seeding time in the variant with plowing, stem density of 0.065 million pcs/ha and a high fertilizer background – 2.59 t/ha. This option shows the best use of moisture to obtain a unit of sunflower yield in 2022 – 872 cubic meters/t.