APPLICATION OF GREEN FERTILIZERS TO RESTORE THE WATER RESISTANCE OF THE SOIL DURING BUCKWHEAT GROWING
Authors:   Sumy National Agrarian University, Ukraine, Mishchenko Yurii , Davydenko Gennadiy ,   Sumy National Agrarian University, Ukraine, Butenko Andriy ,   Sumy National Agrarian University, Ukraine
Published: April 2024

The search for a solution to the problem of reproducing the optimal water resistance of soil aggregates is relevant for modern agricultural production, since their decay leads to clogging of vertical soil drainage, which makes it impossible to form optimal reserves of soil moisture due to the slowdown in the absorption of heavy rains, which we have in the conditions of climate change. The purpose of the article was to determine the most successful combination of the combination of intermediate sowing of siderate and the no-moldboard cultivation, which would contribute to the formation of the highest water resistance of the typical black soil and the productivity of buckwheat. Methodology for assessing the water resistance of the soil was based on the Andrianov method, which characterizes the dynamics of the water resistance of the most valuable aggregates (3-5 mm in size). Using this method, the intensity of wetting of soil particles in stagnant water was determined, which is a certain imitation of the natural process that occurs during early spring snowmelt or torrential rain. Results showed that the water resistance of the structural aggregates of the soil layer 0-30 cm was formed the highest under the option of using radish for siderate – 44.8-47.7%. This option was slightly inferior to the options of using phacelia on siderate and applying 20t/ha of manure, which were at the same level in terms of the content of water-resistant aggregates – 43.1-47.7%. In the case of using the carcass siderate of the predecessor, the water resistance of the soils of the 0-30 cm layer was significantly lower – by 1.1-2.5%, compared to other options of siderates. The increase in water resistance on fertilizer options was accompanied by an increase in the yield of buckwheat seeds; the correlation coefficient between them was quite close r = 0.86. The highest yield of buckwheat seeds was determined on the option of post-harvest siderate of radish – 2.95 t/ha, it was slightly inferior in terms of yield to the option of adding 20 t/ha of manure – 2.82 t/ha and the use of post-harvest siderate of phacelia – 2.66 t/ha. The use of the predecessor carrion siderate for buckwheat and mineral fertilizers was significantly inferior to the option of the post-harvest radish siderate both in terms of the content of the water-resistant structure and in the yield of buckwheat seeds. The highest content of water-resistant aggregates in the soil layer of 0-30 cm was during no-moldboard cultivation of the sideral background of oil radish with a combined flatcut aggregate at a depth of 21-23 (45.7%) and a combined disc at 6-8 cm (44.9%). The 21-23 cm no-moldboard cultivation significantly outperformed the control version of tillage – plowing at 21-23 cm and shelf-less disc tillage at 13-15 cm. The highest yield of buckwheat seeds – 3.42 t/ha, which was significantly different from the rest of the tillages, was obtained with no-moldboard flat-cut cultivation of the sideral background of radishes to a depth of 21-23 cm. The highest correlation dependence of the yield of buckwheat seeds on the water-resistant structure was determined during no-moldboard cultivation – r = 0.97, than for plowing – r = 0.95. Practical implications and Value/originality. The introduction of intermediate crops of siderates will contribute to the full renewal of the water resistance structure due to the use of renewable resources (accumulation of organic matter in the soil due to solar energy). The combination of intermediate siderates with no-moldboard cultivation will ensure the renewal of optimal agrophysical parameters, in particular, the water resistance structure, which will make it possible to better absorb intense rainy atmospheric precipitation in conditions of climate change and more effectively replenish the reserves of productive soil moisture with them.