Evaluation of the Productivity of New Spring Cereal Mixture to Optimize Cultivation under Different Soil Conditions

The aim of the study was to evaluate grain yields, protein yields, and net metabolic energy yields of different combinations of spring types of barley, oat, and wheat arranged in 10 mixtures and grown under different soil types. Naked cultivars of barley and oat were used. The three-year field experiment was conducted at the Agricultural Advisory Centre in Szepietowo, Poland. The study showed that the major factor determining yields of the mixtures was soil quality. Within the better soil (Albic Luvisols), the highest yield was achieved by a mixture of covered barley and wheat and by a mixture of covered barley with covered oats and wheat, but only in treatments with lower sowing density. Moreover, on the better soil, significantly higher protein yields were obtained for mixtures of barley (covered or naked grains) with wheat as compared to the mixture of covered barley with covered oats, or the mixture of covered barley with naked oats and wheat. The highest yields of net metabolic energy, regardless of soil type, were obtained from a mixture of naked barley with wheat, while the lowest from a mixture of covered barley with naked oats and wheat. Mixed sowings increase biodiversity of canopies, which allows a better use of production space. They also increase health and the productivity of plants.

Growing season and productivity of covered oats

Under conditions of the Volga-Vyatka region, which is characterized with the short cool growing season with unstable mode of moistening, 136 acces-sions of covered oats are studied in 2016-2018 on duration of growing sea-son and productivity for the purpose of specification of their classification by precocity, selection of sources for use in breeding on adaptability. Groups of genotypes are determined by precocity: early - the growing season is 65 - 80 days, mid-season 74-88 days, middle-late - 79-93 days, late-ripening 80-103 days. It is established that duration of period seedlings - wax ripeness is stable in these groups; correlation coefficients in pairs between 2016, 2017 and 2018 years of researches were significant positive (r = 0.60-0.87). The index of productivity was less stable; the dependence of productivity on the growing season varied from weak to average significant (r = 0.25-0.45). The mid-season sources are selected forming stable productivity regardless of a condition of agro-climatic resources: k-3624 II-4032-15C-8C-1C-OC, k-3717 CEV/OBS/PAR, and k-3754 AGA/ESM/SAI//CHI/OBS

Species domination in oats phytocenosis and its yield

The paper presents an analysis of oats phytocenosis (the crop and weeds) treated as a competitor group as concerns the species domination developing within it. The study covered oats cultivated on plots after potatoes (in crops rotation system with 25% share of oats) and twice after oats (75% share of oats in the rotation system) during the years 1990-2000. Simpson's species domination ratio and domination structure in the association identifying groups of: dominants, subdominants, influents and accessory species, were computed and studied. Relations between the studied phytocenosis features and weather conditions and oats yield were also determined. It was shown that quantitative relations in the assessed competitor associations were characterized by high variability between years and vegetation periods while no major differences were found between positions in the crop rotation systems. The density of spring phytocenosis during 11 years of studies increased resulting from increasing numbers of weeds appearing; during the late vegetation period they changed the density of associations slightly. In the spring, the groups competitive to the group of dominants consisted usually of the crop and <i>Thlaspi arvense</i> as well as <i>Chenopodium album</i>; with the passage of years their position strengthened. The enrichment of species in phytocenosis was represented mainly by an increase in numbers of accessory species. At the end of vegetation the importance of oats as a dominant increased significantly; during some seasons <i>Chenopodium album</i> co-dominated, however, with the passage of years the group of subdominants grew. Domination ratios for the studied competitor groups decreased with the passage of years, parallel to decrease of oats share in them. The studied features of phytocenosis showed a stronger correlation to the passage of years than the weather development. Invasiveness of weeds increased during consecutive seasons of cultivation while it showed less correlation with the density of oats. Oats yields showed a slight decreasing trend from year to year and was highly determined by the density of the entire weeds assemblage and in the spring by density and share of dominating species.