WATER-SAVING IRRIGATION OF CORN ON THE RECLAIMED LANDS IN ROSTOV REGION

Purpose: to develop a water-saving regime for irrigating corn for grain, which guarantees sustainable productivity with a shortage of water resources on the basis of field research. Materials and methods. The studies were carried out in Rostov region according to generally accepted methods. The soil of the plot is ordinary chernozem. According to water-physical and agrochemical indicators, it is suitable for crop cultivation. The experiment scheme included three options: in option 1 (control), a previously developed irrigation regime was used; in options 2 and 3, from the beginning of the growing season to the phase of tasselling, irrigation rates were given out completely (as in option 1), and then decreased by 15 and 30 %, respectively. Results. The pre-irrigation soil moisture limit in the 0–60 cm layer was maintained at the level of 70–75 % of the minimum water capacity. The soil water regime influenced the plant growth and development. The differences in the onset of plant vegetation phases were observed from the phase of tasselling. The grain firm ripe stage occurred in variant 3 earlier, then in variant 2. The largest linear growth in the flowering phase (269 cm) was recorded in variant 1, which was 3.7 and 5.2 % higher than the indicators of the variants 1 and 2, respectively. The biological yield of corn in option 1 was 12.9 t/ha, which is 10.1 and 16.3 % higher than the water-saving options. According to the calculations of economic efficiency, with a decrease in irrigation rates by 15 %, the cultivation of corn for grain is profitable. Conclusions. As a result of the research, a water-saving irrigation regime for corn for grain was developed and recommended for agricultural production, which provides for nine vegetation irrigations: the first and second – 300 cubic meters/ha each, the third – 400 cubic meters/ha, from the fourth to the ninth ones, irrigation is carried out at a rate reduced by 15 % – 425 cubic meters/ha. Irrigation rate is 3550 cubic meters/ha.