Accumulation of <sup>137</sup>Cs in spring wheat grain at different levels of nitrogen and potassium nutrition in anthropogenic-transformed peat soil
Anthropogenic-transformed peat soils occupy significant areas in the territory of the Republic of Belarus in composition of agricultural land contaminated with radionuclides. A number of studies have been carried out in recent years where diagnostic features, properties and fertility, regimes of mineral nutrition of plants on these soils have been studied. However, studies on radionuclides migration, impact of various agricultural practices on penetration into agricultural crops have not been carried out. The article dwells on study of <sup>137</sup>Cs penetration into spring wheat grain depending on the levels of nitrogen and potassium nutrition of plants when various rates of nitrogen and potassium fertilizers were applied on anthropogenic-transformed peat soil. It has been determined that N<sub>120</sub>P<sub>60</sub>K<sub>120</sub> application reduces <sup>137</sup>Cs level in grain by 15-22 % compared to the control, and when combined with mineral fertilizers, copper-containing fertilizer and plant growth regulator - by 34 %. The minimum accumulation of <sup>137</sup>Cs in spring wheat is determined at nitrogen-potassium ratio of 1 :(1.0-1.2). At the ratio of 1: (0.2-0.6) nitrogen deficiency and increase in radionuclide concentration in grain are observed due to yield decrease. Increase in accumulation of radionuclide in grain is observed at the ratio above 1:1.5. The results of researches make it possible to determine the allowable contamination density values of the anthropogenic-transformed peat soil with <sup>137</sup>Cs and optimal doses of mineral fertilizers for cultivation of food and forage purpose spring wheat.