Influence of tillage and fertilizer systems on productive moisture reserves under agrophytocenosis in crop rotation

Abstract

The paper reveals the results of research on the impact of tillage and fertilizer systems using by-products on moisture reserves in the soil and crop yields in a four-course short-term crop rotation (winter rape – winter wheat – corn for grain – spring barley) on dark gray podzolized soil on the stationary experimental plot of the Institute of Agriculture of Western Polissia NAAS of Ukraine in 2016–2020. Three variants of tillage systems were studied: 1) 20– 22 cm depth moldboard ploughing – control; 2) 10–12 cm depth shallow ploughing; 3) 6–8 cm depth surface ploughing. The system of fertilization involved application of mineral fertilizers N128P90K120 kg/ha of crop rotation area, including the following options for straw: 1) without straw; 2) straw + destructor + N10 kg (ammonium nitrate) per 1 ton of precrop straw; 3) straw + N10 (ammonium nitrate) per 1 ton of pre-crop straw. It has been found out that the reserves of productive moisture in the meter layer of soil on average over the years of research within the period of germination and harvesting (corn, spring barley, winter wheat) in non-moldboard cultivation systems increased by 177.8, 147.1, 99.4 and 74.7, 65.9, 85.4 mm respectively compared with the moldboard ploughing system where moisture reserves were 150.8, 132.8, 73.5 and 55.5, 48.6, 52.6 mm. Under the system of fertilization which provided for the application of straw + N10 and straw + destructor + N10 kg, the reserves of productive moisture in the meter layer were 3.6 and 9.0 mm in the germination period and 10.2 and 14.4 mm in the harvesting period bigger than in the experiment without using straw. The 20–22 cm moldboard ploughing and the 10–12 cm shallow ploughing tillage systems provided higher crop yields compared to the 6–8 cm surface tillage system, which made it possible to obtain 6.91 and 6.50 of winter wheat yields, respectively, 5.37 and 5.13 of spring barley, 11.47 and 11.74 of corn and 3.08 and 3.19 t/ha of winter rape. Resulting from the application of surface tillage system by depth of 6–8 cm, the yield of winter wheat decreased by 1.45, that of spring barley by 1.69, corn by 3.66 and winter rape by 0.31 t/ha. Fertilizer systems based on the use of straw and straw + destructor provided an increase in grain yield respectively: winter wheat by 0.45–0.36 t/ha; corn by 0.60–0.46 t/ha; spring barley by 0.32–0.22 t/ha compared to the option without straw. Key words: productive moisture, crop, straw, tillage, crop rotation, yield.