Integrated control system of segetal vegetation in winter wheat crops in Forest-Steppe conditions

Abstract

As a result of many years of research in a stationary field experiment conducted in the conditions of the northern forest-steppe on Gray forest large-sawn light loamy soil, the regularities of the influence of methods of its main cultivation, doses and terms of herbicide application on the level of contamination of crops with segetal vegetation and the competitiveness of winter wheat in short-term crop rotation were established.It was found that the competitive pressure of weeds on winter wheat both for plowing and flat–cutting loosening to a depth of 20–22 cm was minimal and amounted to 6.9–13.2%, and the crop pressure on weed cenosis was noted in the range of 81.5–84.8%. The use of a herbicide based on D. R. prosulfuron (750 g/kg) increased this indicator to 90%.With flat-cutting loosening, the potential contamination of the upper 0–5-centimeter layer of soil, from which the bulk of weeds germinate, in the crops of the studied crop was 31.3–31.8% higher compared to plowing. Indicators of potential contamination and the rate of germination of weed seeds with this method of basic tillage caused a high level of actual weediness of winter wheat crops in a short-term crop rotation. However, systematic tillage without layer turnover ensured gradual self-cleaning of the lower part of the arable soil layer from weed seeds.The highest yield of winter wheat 6.11 t/ha of grain was obtained during plowing and the autumn period of application of the herbicide based on D. R. prosulfuron (750 g/kg) at a rate of 20 g/ha in the development phase of the BBCH 11–13. The use of the herbicide in autumn compared to spring periods provided an increase in the grain yield by 0.24–0.54 t/ha for plowing and by 0.48–0.64 t/ha for non – polar cultivation.Economically, the most appropriate technology for controlling segetal vegetation in winter wheat crops is recognized, which provides for plowing to a depth of 20–22 cm as the main tillage with the introduction of N80P60K80 and earning by-products of its predecessors into the soil. To increase the effectiveness of crop contamination control in the integrated plant protection system, it is also proposed to use autumn application of a herbicide based on D. R. prosulfuron (750 g/kg) at a dose of 20 g/ha in the phase of 2–3 leaves in the culture.