WATER CONSUMPTION OF WINTER TRITICALE DURING SEED PRODUCTIVITY FORMATION DEPENDING ON THE APPLIED FERTILIZER TYPES AND RATES ON THE IRRIGATED LANDS OF THE SOUTHERN STEPPE OF UKRAINE

The irrigated lands of the Southern Steppe of Ukraine determine the level of total water consumption, the coefficient of water consumption, depending on the types and rates of applied fertilizers during the seed productivity formation of winter triticale. Actuality. Winter triticale as a crop is considered to be insufficiently studied under irrigation, and the Bogadarske variety for seed has not been cultivated before. In this regard, studying the water consumption of triticale when cultivated on seeds, as well as the influence of different rates and types of fertilizers on water consumption, is an important task under climate change on irrigated lands of the Southern Steppe of Ukraine, which in future may serve as a starting point for improving the adaptability of the crops in this region. The purpose of the research was to establish the water consumption features of winter triticale crop, depending on the type and rates of fertilizers on irrigated lands in the Southern Steppe of Ukraine. Methods. The research was conducted in 2013-2016 at the Institute of Irrigation Agriculture of the NAAS in the Ingulets Irrigation System. The soil of the experimental field is dark chestnut medium loam, slightly saline with a humus content of 2.3 %, density - 1.3 g/cm3, withering point - 9.8 %, minimum moisture-holding capacity - 22.4 %. Soil moisture at the experimental sites was determined to a depth of 1.0 m by the thermostat-weighted method in two non-adjoining repetitions. Total water consumption for separate periods of vegetation was determined by the method of water balance, taking into account the initial and final moisture reserve and the amount of precipitation during the period of vegetation. The coefficient of water consumption was established by the ratio of total water consumption for the period of vegetation to the seed yield of winter triticale. Irrigation was performed using a sprinkler unit Dual Console Sprinkler, taking into account a meteorological index and maintaining the soil moisture in the layer of 0-50 cm at 70% of the minimum moisture-holding capacity. Results. Based on the study results the total water consumption, depending on the rates and types of fertilizers, ranged from 3121 to 3258 m3/ha. Despite the fact that water consumption increased as a result of applying fertilizers, but due to higher yields, water consumption for the formation of 1 t of seeds was smaller. Thus, the coefficient of water consumption on the control (reference site) was 867 m3/t. On the variants where nitrogen fertilizers were applied in the rates of N30 – 696-699 m3/t and N60– 686-689 m3/t in an early spring period the plants of winter triticale fed with ammonium nitrate or CAMs consumed moisture more efficiently. On average, from 2013 to 2016, at the background of applying N60P60 and other nitrogen fertilizers of various types and in different rates during the cultivation of winter triticale, about 3.86-5.24 t/ha of seed material were received. Conclusions. It was established that the total water consumption depended on fertilizer application rates and ranged from 3121 to 3258 m3/ha. The moisture was used the most effectively (686-689 m3/t) on the variants where against the background of applying N60P60 an early spring feeding with ammonium nitrate or a carbamide-ammonium mixture (UAM) in a dose of N60 was performed. At the same time, the highest yield of seeds was obtained - 5,19 and 5,24 t/ha, respectively.