The results obtained in the stationary experiment of the Novozybkovskaya Agricultural Experiment Station are presented. In the experiment, single-species crops of yellow lupine, oats and grass mixtures based on them were studied against the background of various doses of potash fertilizers (K180–240). The influence of potash fertilizers on the yield and quality of legumes and cereals and their mixed crops and a decrease in the content of 137Cs in products is considered. It was found that the highest yield was obtained in the K240 variant. The highest level of yield among the studied crops was noted in the grass mixture lupin + oats. In terms of the yield of feed units and exchange energy per hectare, the grass mixture exceeded single-species crops. Studies have established that the guaranteed receipt of normatively clean feed is provided by the use of potash fertilizer at a dose of 240 kg/ha. 137Cs.

The paper presents the results of studies on the study of different doses of potash fertilizers in combination with phosphate fertilizers, both with a separate application and in combination with the biological product Humimax, when cultivating narrow-leaved lupine for green mass, in a field experiment on soddy-podzolic sandy soil (with a pollution density of 20 and more than Ku/km2). The effectiveness of the influence of doses of potash fertilizers and the biopreparation Humimax on the yield, accumulation of 137Cs and the nutritional value of the green mass of the narrow-leaved lupine was studied. It has been established that the use of the Humimax biopreparation provides an increase in the yield of the green mass of lupin up to 69%. The use of the biological product on all backgrounds of fertilization provides an increase in the content of crude protein in the green mass of lupine. Consistently increasing doses of potassium in combination with P45, both when used alone and in combination with a biological product, reduced the specific activity of 137Cs by more than 2.5 times. To reduce the accumulation of 137Cs in the green mass of lupine below the permissible level, the doses of mineral fertilizers should not be lower thanP45K150.