PHOTOSYNTHETIC ACTIVITY OF WINTER WHEAT SOWINGS WHICH DEPEND ON VARIETI AND NUTRITION IN THE SOUTHERN STEPPE OF UKRAINE

The article presents the results of studies about the effectiveness of winter wheat crop cultivation with modern retriever preparations in the background of mineral fertilizers carried out in 2011-2016 on the southern bleak soils in the Ukrainian Steppe. The effects of varietal characteristics of winter wheat and nutrition options on the photosynthetic activity of crops were studied. It was determined that for growing winter wheat after peas should be done under presowing cultivation of mineral fertilizer dose N₃₀P₃₀ (background) and use foliar application crops at the beginning of the restoration spring growing season and beginning exit plants up to complex organic fertilizers Escort – bio in the favorable conditions for the formation of maximum area of leaves in plants and in accordance to the highest value of photosynthetic capacity and net photosynthesis productivity of crops studied varieties. Thus, on average, over the years of research, in this variant of nutrition the largest values of the area of the plant’s leaf surface of winter wheat reached in the ear staining – 53.1-55.0 thousand m²/ha depending on the variety. The maximum photosynthetic potential of crops is determined in the background application of N₃₀P₃₀ and subsequent fertilization of crops with Organic D2. Thus, on average, over the years of research, in the interphase period of planting – the yield of plants in the tube, the photosynthetic potential of the Kol'chuga variety was 0.82 million m²/ha x days, and the Zamozhnіst' variety wos 0.91 million m²/ha x days, which respectively exceeded control by 29.3% and 28.6%. The same trend was observed in the interphase period, the output of plants in the tube – earings. On average, during the years of research, the value of the index of pure productivity of photosynthesis in plant varieties in the control in the interphase period of planting – the yield of plants in the tube varied within 2.01-2.34 g/m² per day, the output of plants in the tube – earings – 5.38-5.92 g/m² per day and depend on the variety. For the introduction of mineral fertilizers under pre-sowing cultivation at a dose of N₃₀P₃₀ and subsequent nutrition of plants with the preparation Organic D2, the value of NPF in Kol'chuga and Zamozhnіst' varieties increased by 29.4-34.7 and 21.2-39.3% depending on the interphase period of plant growth and development. We must consider that the best from all investigated varieties of winter wheat for their complex of indicators was the variety Zamozhnіst'