Potato cultivation on soddy-podzolic soil of feeding crop rotation in the Komi Republic

The arable land of the Republic of Komi is mainly represented by dern-sub-ground soils with low natural fertility, which without the use of fertilizers are quickly subjected to degradation processes, which dramatically reduces their productivity. The aim of the research is to evaluate the efficiency of long-term use of organic and mineral fertilizers in the growing of potatoes in feed crop rotation in the conditions of the Komi Republic. The methodological basis for carrying out the works was comprehensive studies of dern-subhead soils, potato tubers on the sites of a multi-year field experiment laid on the lands of the Institute of Agrobiotechnology of the FRC Komi SC UB RAS in accordance with the «Methodological Instructions of the Geographical Network of Experiments with Fertilizers». A long period of research (more than 40 years) was characterized by different climatic conditions, which affected the number of crops and the quality of potato tubers. There were 7 rotations (14 years) with potato cultivation. Organic fertilizers – peat-avous compost (TNK) in doses of 40 and 80 t/ha (1 and 2 background, respectively) for potatoes and mineral fertilizers – NPK in doses of 1/3; 1/2 and 1 to replenish the carry-out of food elements by plants. The positive effect of the integrated use of organic and mineral fertilizers on the yield and quality of potatoes, as well as on the fertility of soddy-podzolic light loamy medium cultivated soil in fodder crop rotation in the soil and climatic conditions of the Komi Republic, has been established. As a result of the use of six-bed crop rotation and the integrated application of fertilizers, metabolic and hydrolytic acidity decreased in soils from 1978 to 2019; humus content increased by 0.5% (in control); 0.2–0.5% (with three doses of mineral fertilizers); 0.3–1.1% (with TNCs); 0.2–1.6% (with combined use of organic and mineral fertilizers). The largest potato yields were obtained from the combined use of organic (80 t/ha) and mineral fertilizers (1 NPK) and amounted to 37.1 t/ha tubers (8.5 thousand/ha feed units). The largest potato harvests were obtained with the combined use of organic (80 t/ha) and mineral fertilizers (1 NPK) and amounted to 37.1 t/ha of tubers (8.5 thousand/ha of feed units). With this ratio of fertilizers, the high quality of potato tubers was also determined: the starch content was 15.5%, vitamin C – 19.4 mg%, crude protein – 14.1%. The amount of nitrate nitrogen did not exceed the MPC (MPC 250 mg.s.m.). Economic calculations showed that if TNK is added 40 t/ha 1 NPK to the dern-sub-ground soils of agricultural use in the medium-sized zone of the Komi Republic when growing potatoes, the conditional net income will be 68.4 thousand rubles from 1 ha, the cost of 1 t of potatoes – 2.8 thousand rubles, profitability 188.7%.

Key words: fertilizers, soil, crop, potatoes, starch, vitamin C