Scientific Substantiation of the Timing and Rates of Sprinkling Irrigation of Grain Crops in the Conditions of Karakalpakstan

Abstract

Efficient use of water resources in arid and semi-arid regions is essential for the sustainable development of irrigated agriculture. Low precipitation and high evaporation in the Republic of Karakalpakstan require the development of scientifically sound irrigation regimes for crop cultivation. The aim of this study is to determine the optimal timing and application rates for sprinkler irrigation of grain crops in Karakalpakstan and to assess their impact on yield and water use efficiency. Field experiments were conducted on meadow-alluvial, medium loamy, and moderately saline soils of the Nukus district. Soil moisture was maintained at 70-75-70% of the field capacity. During the growing season, four irrigations were applied at rates of 265, 330, 362, and 420 m3/ha. According to the study results, the rate of 4.0 million seeds and N210 per hectare; P140; In the variant with K105 kg/ha mineral fertilizer application, the highest yield was 67.9 centners/ha. With sprinkler irrigation, water consumption per centner of yield was 87-98 m³, while with conventional irrigation, this figure was 117-123 m³. The results demonstrate that sprinkler irrigation technology ensures efficient use of water resources and is essential for increasing sustainable grain yields in Karakalpakstan.