Application of herbicides in spring rape seeds in the conditions of Krasnoyarsk forest steppe

Long-term (2018-2020) field experiments were carried out to study the effect of herbicides of the Clearfield production system on segetal vegetation and the yield of oilseeds of new hybrids of spring rape under the conditions of the Krasnoyarsk forest-steppe. The objects of research are herbicides of the chemical class imidazolinones and imidazolinone-resistant hybrids of spring rape Solar KL and Cebra KL.The soil of the experimental field is a complex of leached and ordinary chernozems. The weather conditions during the growing season differed from the average long-term data by the moisture deficit in 2018 and 2019, and by sufficient moisture in 2020 against the background of increased average monthly air temperatures. The sowing time for spring rape is the 3rd decade of May, the seeding rate is 0.7 million viable grains per hectare. The species composition of the segetal vegetation of the rapeseed agrocenosis has been determined. The type of blockage is juvenile-root-sprouting. Spraying of crops from weeds was carried out in the development phase of spring rape 4-5 true leaves. The selective herbicide Paradox, WRC at a dose of 0.35 L/ha and the continuous herbicide Grader, WGR at a dose of 0.06 L/ha were combined once; adjuvant Galop, W at a dose of 0.2 was used to enhance the contact of the drug with the plant surface. l/ha. Under the influence of a mixture of herbicides in the agrophytocenosis of spring rape, a decrease in the weed component by 98.4 % was established. On plots with the use of herbicide preparations, an increase in the yield of oilseeds was recorded in the Solar KL hybrid by 1.6 times, in the Cebra KL hybrid - by 1.8 times. The highest economic efficiency of the use of Clearfield system herbicides was noted on the crops of the Cebra KL hybrid - 312 percentage points.