Weed plants species composition in spring wheat crops cultivated by intensive and organic technologies

The aim of research is to study the species composition of segetal vegetation in the agrocenosis of spring wheat cultivar Svirel with intensive and organic production technology. The studies were carried out in 2021 in the conditions of the Chulym-Yenisei forest-steppe on the land-use area of LLC Peasant Farm Rodnik, Balakhtinsky District, the Krasnoyarsk Region. Experience options: 1 - control - industrial technology, predecessor - fallow; 2 - organic technology - predecessor - fallow land. The area of each option is 12 hectares. In the control field, wheat was treated with chemical plant protection agents (herbicides, fungicides and insecticides), before sowing, ammonium nitrate was applied at a dose of N30. In the field of organic production, pesticides and agrochemicals were not used. The species composition of the weed flora was determined by the route method. In a field with intensive technology, weediness was taken into account in dynamics: in the tillering phase before spraying with herbicides (initial weeding), then - 15, 30 and 45 days after the application of chemical weeding. In the case of the organic technology, the counts were carried out on similar dates. The weeds of crops in the tillering phase of wheat cultivated using intensive technology belonged to 7 species, 7 families, 3 biological groups, number - 53.4 pcs/m2, biomass weight - 86.6 g/m2. The type of clogging of the cenosis is juvenile taproot. As a result of the use of herbicides and the high competitiveness of wheat in the subsequent periods, weeds were not recorded. In the field of organic production, the weed component is represented by weed-field and natural flora. During the growing season, the species composition changed; in general, during the observation period, 15 species were noted belonging to 10 botanical families, 3 biological groups. The type of clogging is young-perennial. In the milky phase - the beginning of the waxy ripeness of wheat grain, 4 species of annual and 2 species of perennial weed-field plants were noted, the number was 20.7 pcs/m2, the weight of biomass was 1174.8 g/ha. The permanent species of the cenosis are the common pikulnik (Galeopsis tetrahit), the white goosefoot (Chenopodium album), the common campion (Silene vulgaris) and the field thistle (Cirsium arvense). By the end of the growing season, in the total number of weeds, the most significant proportion in the field thistle is 50.2 %, the weight of the biomass is 59.9 %.