THE ROLE OF WATER-RETAINING FERTILIZER IN INCREASING THE EFFICIENCY OF BIOLOGICAL NITROGEN FIXATION AND SOYBEAN PRODUCTIVITY
To address the problem of food security, it is essential to actively develop soybean production in Russia. Besides the fact that soybeans are the source of high-quality vegetable protein, it is important to take into account that they are nitrogen fixers. The problem of climate change forces us to look for methods of dealing with the lack of soil moisture. One of the efficient solutions to this problem is to regulate the soil water regime with the help of functional moisture-retaining fertilizers (FMR). However, the effect of these agents on the productivity and quality of soybean grain in woodland grass areas if the Central Black-earth region remains insufficiently studied. Therefore, studying the effects of FMR as well as the effect of inoculants on the biological nitrogen fixation of soybean crops is a relevant question, which is the purpose of our research. The field experiment was carried out in the conditions of the woodland grass area of the Central Park in 2019-2021. It was discovered that the mass of nodules on the "Highcoat +FMR" variant in the blossom phase was 35.73 g/m2, and on the "Control+FMR" variant - 7.97 g/m2, respectively. The number of nodules on the soybean root system had the same correlation: the best option was "Highcoat+ absorber" (1279.3 pcs/m2), which exceeded the "Control + absorber" option by 6 times for this indicator. The highest values of nitrogen by soybean crops were detected during the seed filling phase on the variant with the use of the agent "Highcoat Super" after the application of FMR (52.4 kg / ha). The lowest value of biological nitrogen fixation was detected in the control (without the application of FMR), where it amounted to 30.97 kg/ha, which is 41% lower than the best variant "Highcoat + absorber". The use of FMR and inoculants had a positive effect on the yield. As a result, in the variant "Highcoat + absorber", the yield is 34.9% higher than in the "Control+FMR" and 17.4% higher than in the "Highcoat Super" (without replacing it with FMR).