Regulation of soybean water regime under tillage and fertilisation for sustainable agriculture

Reduced soil moisture due to climate change can reduce crop yields, which negatively impacts food security and food system resilience. Therefore, the study aimed to determine the effect of tillage and fertilisation systems on the accumulation of available soil moisture and soybean yields. The research was conducted on chornozem podsolised medium loamy soil in 2019-2022. The research methods used were field, laboratory, comparative and correlation. Soybeans were grown in a 4-field crop rotation according to the generally accepted technology for the conditions of the study region. The dynamics of available moisture reserves in 0-20, 0-40 and 0-100 cm soil layers during the growing season under the influence of tillage and fertilisation systems were presented. The reserves of productive moisture in the soil and the yield of soybean grain under the influence of mouldboard, flat-cut, chisel, disc and differentiated tillage on mineral and organomineral nutrition backgrounds were determined. The maximum reserves of available moisture in the root layer of the soil (0-20 cm) on mineral and organic-mineral fertiliser backgrounds were observed in the phase of full germination and flowering of soybeans under chisel tillage, and the minimum under mouldboard tillage. The highest soybean grain yields were obtained with mineral and organo-mineral fertilisation and chisel tillage. In the flowering phase of soybeans under the influence of soil tillage systems, a medium correlation (r = 0.66) was found between grain yield and available moisture reserves in the 0-40 cm soil layer under mineral fertilisation and a weak correlation (r =0.36) under organic-mineral fertilisation. The fertiliser system had the greatest impact on soybean grain yields (62.5%). The study results can be used in informed decision-making on sustainable soil management and conservation to promote global food security and mitigate climate change