Dynamics of the availability of available moisture in soil by optimization of sowing time and density of statement of sunflower plants in the Right-Bank Steppe of Ukraine

Abstract

The article presents the results of scientific researches on the influence of sowing time and density of standing of sunflower plants on the dynamics of the content of available moisture in soil in the conditions of the Right-bank Steppe of Ukraine. One of the decisive factors for the achievement of high and sustainable crop yields in the conditions of unstable moistening of the Right-Bank Steppe of Ukraine is the accumulation and rational use of moisture, which is one of the most important unregulated factors limiting the yield. On average, during the years of research, the most available moisture in the 0-10 cm soil layer was in the first sowing period - when it was heated to a depth of seed 5 - 6 0C and was 25.0 mm. It was found that the moisture available to plants in the meter layer of soil at the time of sowing remained high and significantly influenced the dynamics of emergence of seedlings. On average, during the years of research, the most available moisture in the 0-100 cm soil layer was during the first sowing period - for warming it to a depth of seed 5 - 6 0C - 178.6 mm. In such conditions, quite favorable conditions of moistening of the sowing layer of soil are created in order to receive friendly and complete seedlings when sowing in the first - second decade of April. However, at the end of the third decade of April, there is a significant decrease in gross moisture reserves in the sowing and deeper layers of soil, which limits the productivity of crops.