Development and productivity of the grass stands of the birdsfoot trefoil (Lotus corniculatus) on different fertilization backgrounds in the conditions of the dry meadows of the Northern Forest-Steppe

Abstract

Goal. To detect the reaction of birdsfoot plants in pure sowing and in grass mixes with brome grass to liming, the use of mineral and bacterial fertilizers. To determine the regularities of the development of birdsfoot grass stands and develop technological elements to influence the formation of high-productivity phytocenoses, and improve the quality of feed. Methods. Field (accounting for the yield of green mass by the weight method from each plot), laboratory (determining the content of dry matter in the fodder mass by drying plant samples in a thermostat at a temperature of 100–105 °C), mathematical (processing yield data by the method of dispersion analysis), system analysis (analysis of all impact factors separately and in combination). Results. Field researches of development and productivity of birdsfoot were carried out on experimental plots of SE DF «Chabany» of NSC «Institute of Agriculture of NAAS». The soil of the experimental sites was dark-gray forest. They studied the development and formation of birdsfoot in pure sowing and binary grass mixes with brome grass, depending on weather and climatic conditions, botanical composition, and density of cenoses, fertilizer systems, terms of substraction of the above-ground mass. It was determined that at the beginning of the growing season, birdsfoot plants developed more intensively in grass stands against the background of phosphorus-potassium fertilizers or the use of a phosphorylation bacterial preparation. It was noted that the best structure of the grass stand with a vegetation density of 1018–1269 shoots/m2 for 4 years of use was formed by single-species crops of birdsfoot for liming and application of complete mineral fertilizer N20R30K45, as well as in the version with liming and combined action of nitrogen-fixing and phosphorylating bacterial preparations. Conclusions. The highest productivity (8.5–9.2 tons/ha of dry matter), on average, over 4 years of use, was provided by grass stands of birdsfoot in pure sowing and a binary mixture with brome grass for liming the soil and applying full mineral fertilizer N20P30K45, as well as in the version with liming and combined inoculation of birdsfoot seeds with bacterial fertilizers — nitrogenfixing Azotophytamine®-p and phosphorylating Polymixobacterin. The combined use of these drugs on grass stands made it possible to successfully grow birdsfoot in pure form with a productivity of 8.5–9.0, in a grass mixture with brome grass, 7.4–8.6 tons/ha of dry matter without the use of mineral fertilizers.