The purpose of this work is to evaluate the effect of biochar on the physico-chemical properties of the soil and morphometric and some chemical characteristics of durum wheat (Triticum durum L.) and indirectly assess the availability of macronutrients in the soil-biochar system based on the state of plants.
Methods. Biochar was obtained from birch sawdust at a temperature of 500 °C and was applied in the amount of 2 % of the weight of air-dry soil.
Results. As a result of the vegetation experiment, it was revealed that the application of biochar led to changes in the properties of heavy-loamy agro-soddy-podzolic soil - a significant increase in the pH values of the water extract and the total nitrogen content, but at the same time - to a significant decrease in the content of total organic carbon content. Despite the improvement of some soil characteristics, the application of biochar did not affect the height of plants, leaf weight, root weight, nitrogen and phosphorus content in leaves and yield, and also negatively affected the total weight of plants and the weight of grains, which decreased by 15 % and 18 %, respectively, compared to control. The application of biochar had an impact on the structure of the wheat root system - its branching increased, while the diameter of the absorbing roots significantly decreased. The experiment also showed an increase in mycorrhization of roots due to the functional structures of the fungus - arbuscules and vesicles. The scientific novelty lies that the application of biochar from birch sawdust, despite the improvement of some physico-chemical characteristics of the soil, negatively affects the growth of wheat. The reaction of the aboveground parts of plants and the root system indirectly indicates a decrease in the availability of nutrients in the soil-biochar system. The results obtained in the work can be used to develop technologies for the use of biochar meliorants in various soils.