Systems of basic tillage and weed infestation of the spring barley crops

In the course of research the influence of duration of exposure to different tillage systems on the weed infestation of crops and yield of spring barley was determined. Stationary field experiments were carried out in the Scientific Research Institute of Agriculture for Northern Trans-Ural Region – Branch of Federal State Institutions Federal Research Centre Tyumen Scientific Centre of Siberian Branch of the Russian Academy of Sciences – in the northern forest-steppe of the Tyumen Oblast. Observations (2018-2022) were carried out in the 7th rotation of grain-fallow crop rotation: complete fallow – winter rye – spring wheat – spring wheat – spring barley. The following systems of basic tillage were compared: moldboard, nonmoldboard, combined, differentiated, sweep and shallow systems. The soil of the experimental plot is dark gray forest soil, heavy loamy, typical for the zone by its characteristics. A mixture of preparations against dicotyledonous and cereal weeds was applied as a general background. Prolonged (during 35 years) application of basic tillage systems of different intensities in cereal crops in grain and fallow crop rotation using a mixture of herbicides against mixed type of weeding contributed to the formation of low and medium degree of weed infestation, mainly annual small-seeded weeds. At the same time, the indicator of total damage (the mass of weeds is 1.13–4.47 % of the biomass of cultivated plants) was low. The moldboard system of basic tillage proved to be the most effective in combating weeds. The highest weed infestation was observed in the nonmoldboard system (243.3 pcs./m2): in spring – 1.8 times more by number, in autumn - 4 times more by weight in comparison with the moldboard tillage system. When cultivating cereals in crop rotation with the use of complex chemicalization means, the possibility of using resource-saving tillage systems is justified by maintaining a low level of weed infestation and its harmfulness, the absence of negative impact on yield.