Effect of lupine straw on potato yield and biological state of soddy-podzolic soil

Post-harvest plant residues, mainly straw of cereals and legumes, are the most important readily available biological resource for the reproduction of soil fertility. However, the data on their effectiveness and influence on the biological properties of the soil in the scientific literature are not unambiguous and contradictory. The results of long-term experiments on the study of the effectiveness of post-harvest residues of various crops are very few. The role of lupine as a green manure for increasing the productivity of potatoes is well studied, however, there are practically no data on the effect of lupine straw grown for grain on potato productivity. Studies in a long-term field experiment have established that the incorporation of lupine straw into the soil (against the background of the previous long-term introduction of straw of grain and leguminous crops of grain-tilled crop rotation), both in combination with mineral fertilizers and in pure form, contributed to an increase in the number of ecological-trophic groups of microorganisms, microbial biomass, nitrification activity of soddy-podzolic soil. The activation of microbial activity, increasing the supply of plants with available nutrients, promoted an increase in potato productivity, as well as an increase in the content of vitamin C and starchiness of tubers. A close correlation was noted between potato yield and determined microbiological parameters (r = 0.62-0.87), which indicates that the general level of biogenicity of soddy-podzolic soil, regulated by the introduction of straw of grain and leguminous crops, largely determines the level of its effective fertility and crop productivity.