THE INFLUENCE OF VARIOUS HERBICIDES ON THE PRODUCTIVITY OF SOYBEANS IN THE CONDITIONS OF THE FOREST-STEPPE ZONE OF THE RSO-ALANIA

Abstract

The article considers the influence of various doses of herbicides on weed vegetation, the growth and development of crops, the quality of the products obtained, the matrix diversity of seeds and yield. The combination of Pivot 0.8; Harmony 8 g/ha had the greatest toxic effect on weeds. The contamination of crops with this combination decreased by 93.6%, and the reduction in the mass of weeds by 95.3%. The efficiency of the Trophy 2.0 variant was also very high; Harmony 8 g / ha (the reduction in the number of weeds was 92.3%, and the mass was 93.7%). The efficiency of the options Pivot 0.8; Pulsar 0.8 and Trophy 2.0; Pulsar 0.8 was significantly lower. The combination of Trophy 2.0; Pulsar 0.8 had a strong inhibitory effect on the number of nodules and their raw mass. The effectiveness of herbicides largely depended on the botanical composition of weeds and the degree of their resistance to drugs, the timing and doses of their use, precipitation and precipitation distribution after chemical treatments. In conditions of elevated air and soil temperatures, the sensitivity of weeds to all herbicides increased significantly. The introduction of Trophy 2.0; Harmony 8g / ha significantly inhibited soybean seedlings, causing a slight decrease in the density of seedlings. The combination of Trophy 2.0; Pulsar 0.8 oppressed soybeans in the first half of the growing season, causing yellowing of plants. The introduction of herbicides contributed to an increase in productivity by increasing the number of beans and grains per plant by 18.4 – 38.9%. The use of the Pivot 0.8; Harmony 8 g/ha option led to an increase in the mass of 1000 seeds by 9-11 g and did not affect the germination energy and seed germination. The drugs used did not affect the onset of soybean seedlings, but their unfriendly (uneven) and longer germination was observed. Soil herbicides reduced the density of standing plants by 0.4-1.1%, insurance herbicides-by 2.7-3.3%. Weeds take out a significant amount of nutrients from the soil. In the control variant, the total removal of nitrogen by weeds was 109.2 kg/ha, phosphorus-16.4, potassium – 81.61 kg/ha. In the best variant (Pivot 0.8; Harmony 8 g/ha), nitrogen removal was 6.69 kg/ha, phosphorus-1.11, potassium – 5.13 kg/ha. The saved amount of nitrogen would be enough to form 12.2 c of soy grain, phosphorus and potassium, respectively, 6.63 and 20.67 c.