Shallow and Combined Tillage of Black Soil Typical at Different Specialisation in Agricultural Production in the Left Bank Forest Steppe of Ukraine

Abstract

The article presents the results of long-term experimental studies on the effect of different methods of main tillage on soil fertility and crop productivity when applying different degrees of fertilization. Field research was conducted during 2013-2020 on the lands of the Poltava Research Station of the Institute of Pig Breeding and Agro-Industrial Production of the National Academy of Agricultural Sciences. It has been established that the systematic use of organic and organic and-mineral fertilization systems improves the nutrient regime of typical black soil with differentiation of the arable layer by the amount of phosphorus and potassium when applying long-term minimal loosening. There is a tendency towards an increase in density in the layers of 20-40 and 40-60 cm when applying systematic shallow tillage, where this indicator exceeds the upper limit of the optimal range of 1,0-1,3 g/cm3. Application of manure and mineral fertilizers compared to surface loosening makes it possible to additionally annually sequester 0,3-0,4 t/ha of carbon, which is equivalent to 1,2-1,6 t of carbon dioxide. By the average multi-year yield of corn per silage, shallow loosening is inferior to combined tillage by an average of 10%. Tendencies to a decrease in the average long-term productivity of soybean, spring barley, and pea crops when using minimal tillage compared to the combined one are manifested only in certain fertilizer options. Under optimal conditions of heat and moisture supply, the ratio of grain and straw in soybeans decreases. On winter wheat, after peas, there is a tendency towards the preference of shallow loosening. The ratio of wheat grain to straw increases significantly under favorable conditions. Corn responds better to the combined tillage system, which prevails shallow loosening in terms of grain yield by the fertilizer options by 6-10%. Under favorable conditions, the ratio of stems to grain increases significantly, especially on fertilized grounds. From the studied crops, the productivity of sugar beets fluctuates to a greater extent to the conditions of the year, and to a lesser extent - winter wheat, grown after peas and corn for grain. By the average long-term crop productivity, shallow tillage is inferior to combined tillage by 4-8% having a confidence level of 5%. When applying manure, it is advisable to use a combined system of soil tillage, for plant-oriented agrarian production, it is economically advisable to use surface loosening for all crops.