Increasing rice productivity by developing optimal types of mineral and organic nutrition in conditions of water resource shortage and climatic anomalies in the South of Russia

Achieving high rice yields on saline soils in the Azov floodplains of Krasnodar Krai is fraught with numerous challenges. One of these is the lack of a fully developed system for applying mineral fertilizers in these conditions, although general principles for their use in rice crops have been developed. The aim of this study was to address two issues: assess the impact of different forms of nitrogen on rice growth and productivity on meadowmarsh soils of the Lower Kuban region under various types of soil salinity, and evaluate the effectiveness of organic fertilizers to determine optimal nitrogen fertilizer application rates and the amount of nitrogen, phosphorus, and potassium removed with the crop. The study was conducted in 2024-2025 at the Kuban experimental farm of the I. T. Trubilin Kuban State Agrarian University in Krasnodar and the Golovin Konstantin Viktorovich peasant farm in the Kalininsky District of Krasnodar Krai. The results of the first task revealed quantitative relationships between the influence of salinity type on rice yield in meadow-marsh soils and leaf photosynthetic activity. The results of the second task demonstrated that alfalfa is the best organic fertilizer, with minimal yield fluctuations, which cannot be achieved when applying manure and peat. The optimal nitrogen fertilizer application rate for meadow-chernozem soils has been proven to be 120 kg/ha. However, the application rate should be halved when applied in combination with alfalfa (10 t/ha). Compared to the control, the removal of nitrogen by the crop with organic fertilizers was found to be 20-60% higher for nitrogen, 4-40% higher for phosphorus, and 28-30% higher for potassium.