2. Object of research: processes of growth, development, formation of crop yield and grain quality of different varieties of spring barley depending on the use of mineral fertilizers, growth regulators for cultivation after different predecessors in the eastern part of the Northern Steppe of Ukraine. The purpose of research: to scientifically substantiate existing and develop new effective agrobiological measures to increase grain productivity of spring barley plants, taking into account changes in weather factors, morphobiological characteristics of varieties, their response to fertilizers and growth regulators after different predecessors. Research methods: general science: field; laboratory; measuring and weighting; computational and methods of mathematical statistics: variance, correlation and graphical display of data. Also used special: dialectical, hypothesis, synthesis, induction, statistical, observation, economic and mathematical. Results: improved existing and developed effective technological measures for growing spring barley, which provide for sowing after the predecessor of peas on the background of pre-sowing application of mineral fertilizers at a dose of N15P15, and after sunflower – N30P30; implementation of pre-sowing treatment of seeds with growth regulator Gumisol Plus (1 l/t) or microfertilizer Syzam (250 g/t) followed by spraying of plants in the tillering phase with Gumisol Plus (3 l/ha) or Syzam (250 g/ha), which provides formation of crop yield not lower than 3,5–4,2 t/ha of grain of the required purpose with high indicators of quality and economic efficiency of production. The results of the research were tested in production conditions and are annually implemented in the farms of the Northern Steppe of various forms of ownership on an area of more than 5 thous. ha, providing an increase in grain yield and economic effect at 2,3–5,6 MIO UAH. Novelty: created a variety of spring barley Shidnyi (patent № 120027) and a brewing variety of spring barley Stepovyk (patent № 120028); developed a method of growing cereals (utility model patent № 103811); the reaction of plants of two varieties of spring barley Shidnyi and Stepovyk to predecessors, doses of mineral fertilizers, application of growth regulators in the conditions of the eastern part of the Northern Steppe for grain formation with corresponding quality indicators was revealed. The existing methods of varietal technology of spring barley cultivation have been improved, which allow to fully realize the crop yield and grain quality in the conditions of the eastern part of the Northern Steppe, to reduce production costs. Scientific approaches to the formation of varietal agricultural techniques for growing spring barley in the eastern part of the Northern Steppe have been further developed; economic assessment of the feasibility of implementing technological solutions in the cultivation of different varieties of spring barley. Field: agricultural sciences.
