Influence of weather conditions and varietal characteristics on the formation of structural elements of soft winter wheat yield in the Northern Steppe

Probability. The key task of the agrarian sector of the Ukrainian economy is to ensure a stable winter wheat yield in the face of climate change and the introduction of new intensive varie-ties. It should be noted that most of the mechanisms of formation of increased productivity of win-ter wheat are not yet fully understood and require additional research. Issues. Productivity of winter wheat depends largely on the variety and influence of environmental factors, and is closely related to all processes of plant growth and development. Scientific substantiation of optimal development of its main structural elements is necessary to further increase the yield. Purpose. To identify the influence of weather conditions and varietal characteristics on the formation of yield structure ele-ments of soft winter wheat in the Northern Steppe. Materials and methods. The research was con-ducted on black fallow (on the background N0-30P60K30) and after spring barley (on the background N60P60K30) in the fields of the Research Farm "Dnipro" SE Institute of Grain Crops NAAS in ac-cordance with generally accepted recommendations. Results. The productive plant density of winter wheat is one of the main elements of the yield structure, and the most critical conditions for the formation of plant density were in the 2011/12 growing year. The number of productive stems after spring barley depending on the variety was 166–215 pcs/m2, and on black fallow – 249–416 pcs/m2. The level of biological yield depending on the predecessor varied between 194–264 and 369–478 g/m2. In the years of research, the maximum yield was formed on black fallow: in 2012–2014 for Lytanivka and Zamozhnist varieties (664 and 658 g/m2), and in 2016-2018 - in Pylypivka variety (766 g/m2). Conclusions. Hydrothermal factors during the growing season have a significant effect on the condition of winter crops. Arid conditions in autumn and spring-summer significantly reduce the productive plant density, and, consequently, biological yield, especially after non-fallow prede-cessors. It was determined that some varietal pattern are in the formation of next structural yield elements, such as ear length, number of productive spikelets and grains per ear, thousand grain weight. Keywords: winter wheat, variety, predecessor, productive plant density, ear grain weight, thousand grain weight, biological yield.