Effects of precision irrigation on water regime and productivity of winter wheat

The aim of the research was to establish the effect of precision irrigation with varying mineral fertilizer availability on winter wheat productivity. Studies were carried out on irrigated arable land in the Rostov region. The test scheme included 3 replications. The climate of the research area is arid but not hot enough. The sum of temperatures for growing period is in the range of 3000…3200 ºC, the average annual precipitation is 470 mm, for the growing period - 285 mm. The soil cover of the experimental site is chernozem. According to the granulometric composition of the soil, the entire profile is represented mainly by heavy loam, turning into medium loam at a depth of 130-160 cm. The structural state in dry sieving and the water resistance of the aggregates are characterized as excellent. The lowest water-holding capacity for 0-60-centimeter layer is 28.3 %, which is good according to the existing classification. Soil density in 0.6 m layer is 1.27 t/m3, and in 1.0 m layer - 1.33 t/m3. Differentiated doses of fertilizers against the background of irrigation technologies studied in variants had a significant impact on productivity of winter wheat. Thus, in the variants with no irrigation, water consumption coefficient of winter wheat was 890.8 to 1343.6 m3/t; using the recommended irrigation system reduced its value to 725.9…1327.3 m3/t, and the precision irrigation technology provided a reduction in the value of water consumption coefficient to 681.6…1147.6 m3/t. The conducted studies revealed advantage of precision irrigation technology and mineral fertilizers, the use of which in different years provided higher winter crop yield by an average of 0.55 t/ha in comparison with the recommended technology, and, in comparison with variants without irrigation - by 3.49 t/ha. The introduction of modern high-precision irrigation technologies will make agricultural products produced on irrigated land more competitive.