The research on irrigation water use at growing of agricultural crops (spring barley cv. Preria, potato cv. Zhukovskiy ranniy, pumpkin cv. Vitaminnaya, alfalfa cv. Rostovskaya 60, soybean cv. Tavria, sunflower cv. Mechta) was conducted in Semikarakorskiy district of the Rostov region in 2011–2013. There were three variants of irrigation regime: intensive (irrigation at 75–80 % FC in soil layer 0.6 m), water-saving (irrigation in critical period by the norm calculated on the actual soil moisture in a layer of 0.6 m), and rainfed (without irrigation). Agrotechnology met zonal requirements. Field experiments were carried out using conventional methods. It was established that intensive irrigation comparing with rainfed conditions provided yield increase for potato in 2.3 times, pumpkin – in 2.2 times, sunflower – in 2.0 times, barley, alfalfa, and soybean – in 1.6–1.7 times. At water-saving irrigation regime, the yield of crops decreased by 15.6–37.4 % comparing with intensive one while irrigation water savings were 380–1570 m³/ha. Growing of pumpkin and spring barley under intensive irrigation provided the lowest coefficients of water consumption, the least expenditure of water for 1 ton of additional production, and the greatest yield per 100 m³ of irrigation water. Water-saving variant provided more rational use of soil moisture and efficient use of irrigation water for potato, soybean, sunflower, and alfalfa. The least coefficients of water consumption were marked for potato (110 m³/t) and alfalfa (399 m³/t). The greatest additional yield per 100 m³ of irrigation water was obtained for potato (1.82 t). Water-saving variant enables to preserve irrigation water up to 1140–1570 m³/ha.
Keywords: irrigation water, agricultural crop, irrigation, yield, coefficient of water consumption, additional production.
