Praktyczne i ekologiczne aspekty chemizacji w produkcji zyta ozimego na polnocnym wschodzie nieczarnoziemu Federacji Rosyjskiej

Badano wpływ wzrastających dawek nawozów azotowych oraz środków ochrony roślin przed chorobami, zapobiegających wylęganiu, przy oddzielnym i łącznym ich stosowaniu, na fitosanitarny stan zasiewów, plonowanie i jakość plonu, technologiczne i wypiekowe właściwości ziarna krótkołodygowego żyta ozimego, zmiany liczebności podstawowych grup glebowej mikroflory, dynamikę resztek pestycydów pozostających w glebie i w roślinach, gromadzenie resztek pestycydów, a także metali ciężkich (Pb, Ni, Cr, Cu i Zn) w ziarnie i słomie żyta ozimego.

Winter rye is one of the basic crops grown in north-eastern non-black earth zone covering about 30% sown area. It is commonly cultivated because of high frost and drought resistance and low habitat requirements. The objective of the research was to determine the effects of differentiated doses of nitrogen fertilizers and chemicals preventing plant pathogens and crop lodging at separate and joint application, on the phytosanitary state of crops, yielding and yield quality, technological and baking properties of winter rye grain as well as on the quantitative changes in soil microflora, pesticide residues in the soil and plants and the cumulation of pesticide residues and heavy metals (Pb, Ni, Cr, Cu, Zn) either, in grain and straw of the winter rye. The design of plot experiment included 32 variants at 4 levels of nitrogen fertilization: (1) zero N, (2) 60 kg N before sowing, (3) 60 kg N before sowing + 30 kg N spring top-dressing, (4) 60 kg N before sowing + 30 kg N spring top-dressing + 30 kg N at shooting. The fungicides such as Fundosol and Tilt as well as Kamposan growth retardant were used separately and in combinations, with threefold replication. The P+K pre-sowing fertilization was applied at a rate 90 kg/ha. Increasing N-fertilization level conduced to extending the infestation of winter rye plants with white mould and cereal rust. Pesticide application, especially at medium and high N-fertilization levels, significantly improved phytosanitary condition of winter rye crop. The efficiency of N-fertilizers application could be increased by their complex use together with the fungicides. Complex application of the pesticides did not increase the cumulation of heavy metals (Pb, Ni, Cr, Cu, Zn) in grain nor in the straw of winter rye grown on green manures (rape, peas) and on the soils slightly contaminated withthese elements.