Tkach M. Yіeld and graіn qualіty of rіce varіetіes dependіng on sowіng dates and fertіlіzer rates

The object of research - the processes of growth, development and formation of the crop, structural elements of productivity and quality of rice grain depending on the timing of sowing and doses of fertilizers on dark chestnut soil in southern Ukraine. The aim of the study was to study the peculiarities of growth, grain yield and its quality in rice varieties under the influence of sowing dates and doses of fertilizers when grown in southern Ukraine. Methods - in accordance with the tasks and topics of the dissertation to obtain research results were used field and laboratory methods; visual and measuring-weight - for observation of phases of development, definition of biometric indicators of plants by formation of their productivity; biochemical - to determine the quality of rice grain; mathematical and statistical - to assess the reliability of the obtained research results; calculation and comparison - to determine the economic efficiency of fertilizers for the studied varieties of rice. Results - it is established that the maximum yield of rice grain with the best indicators of its quality - protein and starch content and yield, yield of cereals and whole kernel, vitreous, weight of 1000 grains, etc. doses of fertilizers 120 kg / ha active ingredient nitrogen and 30 kg / ha a. i. phosphorus; for the variety Consul to sow in the first decade of May with the introduction of an increased dose of fertilizer 180 kg / ha a. i. nitrogen and 60 kg / ha a. i. phosphorus grain yield is formed at the level of 85-95 kg / ha with high crop profitability and preservation of soil fertility of rice systems. Novelty - is that for the first time for rice varieties Lazurite, Marshall, Consul for growing them on dark chestnut soil in southern Ukraine studied the growth and development of rice plants during the growing season - the dynamics of weight growth, leaf surface area, crop formation on levels of 85-95 c / ha with high quality of grain and cereals under the influence of the studied factors. Scientific value - to obtain a high level of grain yield and its quality, it is advisable to apply mineral fertilizers in doses of N180P60 for crops of rice variety - Consul. The dose of fertilizer for crops of varieties Lazurite, Marshall should not exceed N120P30. To increase the yield of rice grain and improve its technological properties, it is better to sow rice in the third decade of April. Variety of rice Lazurite should be sown in mid-May, to improve its technological properties and, accordingly, increase the level of profit. For growing rice varieties with high quality, it is promising to grow them considering the biological properties of the variety and early sowing with a dose of fertilizer N180P60. Sector – agriculture, selection.