In a long-term places, located on the experimental fields of Siberian Research Institute of Agriculture (Omsk), the schemes of field crop rotations were modernized by introducing oil crops (rapeseed, soybean) into rotation and replacing the repeated wheat crops with barley and oats. Accounting of grain crops productivity and accompanying observations were carried out in three field rotations of different lengths of rotation (four- and five-field) and on permanent sowing. The repetition of the experiments is fourfold. The system of agrotechnical measures recommended for the zone of the forest-steppe of Western Siberia was applied. The study of predecessors in the cultivation of crops for various purposes was carried out in field experiments using conventional methods. The humus content for rotation in the soil layer of 0-40 cm increased by 0.19% in the crop rotation “rapeseed - wheat spring wheat - barley - soybean - spring wheat”. The largest accumulation of humus (0.83%) was in the rotation “soybean - spring wheat - barley – oats”. During the years of research wheat productivity varied from 0.82 to 2.22 tons per hectare. Wheat was the first crop in all its predecessors to form grains, on average, by 0.3-0.5 tons per hectare, than the second crop. The yield of soybeans in the crop rotation was 1.23-1.78 tons per hectare. The productivity of rapeseed was low, its productivity over the years was 1.31 tons per hectare. Grain-fodder crops (barley, oats) averaged 0.4-0.6 tons per hectare, higher than the spring wheat productivity in the alternating rotation. The maximum yield of grain from a hectare of arable land was noted in the crop-steam rotation and amounted to 1.7 tons. An increase in the yield of feed-protein units was observed in crop rotations saturated with oil crops (rapeseed and soybean) and amounted to 3.4-4.0 tons per hectare. The economic calculation showed that the cultivation of field crops in the rotational crop rotation of “soybean - wheat - barley – oats” increased profitability by 44%, net income - by half, in comparison with the control variant. The obtained materials can be used to develop schemes of field crop rotations for the zone of the forest-steppe of Western Siberia.
Economic efficiency of fungicide application on spring wheat in the southern forest-steppe of Western Siberia