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W jednoczynnikowym doświadczeniu polowym przeprowadzonym w latach 2009-2011 uprawiano jęczmień, owies, pszenicę i pszenżyto oraz trójskładnikowe mieszanki tych zbóż, a także mieszan¬kę zawierającą wszystkie gatunki. Zróżnicowanie gatunkowe zasiewów miało niewielki wpływ na zachwaszczenie wtórne łanów. Nie stwierdzono istotnych różnic w liczbie i masie chwastów w dwóch pierwszych latach doświadczenia oraz średnio w trzyleciu. W 2011 r., wśród zasiewów wielogatunkowych, najmniejszą liczbą i masą chwastów charakteryzował się łan mieszanki jęcz¬mienia, owsa i pszenżyta. Istotnie większym zachwaszczeniem odznaczały się: pszenżyto oraz mieszanka jęczmienia, pszenicy i pszenżyta. Średnio w trzyleciu efekt odchwaszczający mieszanki stwierdzono w zasiewach: jęczmienia z owsem i pszenicą, jęczmienia z owsem i pszenżytem oraz czteroskładnikowego.
Atmospheric air may contain a variety of biological components, e.g. microorganisms, which may be harmful to the internal environment of caves and the health of its visitors. Our study aimed at mycological evaluation of the air inside and outside of Niedźwiedzia Cave in Poland. Between 123 and 214 CFU fungi per 1m³ of air were isolated from the air sampled in the cave, and ca. 600 CFU from the air sampled outside of it. Cladosporium herbarum and Rhizopus stolonifer are the species most frequently isolated from the air inside the cave and Cladosporium herbarum from the outside.
A single-factor field experiment was conducted in 2009-2011 on light soil to determine productivity of multi-species mixtures of barley, oat, wheat and triticale. The cereals were grown in 3- and 4-species mixtures. The objective of this study was to determine if these highly diverse cereal mixtures are more productive and yield more stable than pure stand cereals. Mixtures did not differ in grain yield and each of them yielded between the highest and the lowest yielding component grown in pure stand. All mixtures yielded more stable than pure stands of barley, oat and triticale. Oat-wheat-triticale mixture yielded more grain protein than pure stand cereals and mixtures with the exception of barley-wheat-triticale mixture. Growing cereals in mixtures caused reduction in productive tillering of barley and 1000-grain weight of oat, while increased number of grains and grain weight per spike of triticale.
In a field experiment conducted in 2009-2011 on light soil barley, oat, wheat and triticale were grown in 3- and 4-species mixtures and in pure stands. The aim of the study was to assess competition between species in mixtures and to determine yield advantage of mixtures over their components grown in pure stands. Competitive hierarchy observed at full maturity of cereals in 4-species mixture clearly reflected hierarchies seen in 3-species mixtures, with triticale showing the highest competitive ability followed by wheat then oat and finally barley. Five weeks after plant emergence all mixtures were more productive than pure stands (LER>1) while no biomass or grain yield advantage of mixtures over pure stands was found at full maturity of cereals.
The study aimed at being a mycological evaluation of spring barley grain harvested from the barley-pea intercrop, on which different methods of weed control had been used. The field experiment was carried out during 2010-12 and it was conducted using randomized block design in four replicates. Weed control was mechanical (spring-tine harrow treatment of variable intensity) and chemical (herbicide Chwastox Extra 300 SL – 3L per ha). Fungal colonization tests were carried out on disinfected and non-disinfected grains. The research has shown statistically significant differences in the total number of fungi isolated from disinfected and non-disinfected grains in particular years of study, between the objects, and in some cases between the study years. The fungus most frequently isolated from all variants of the experiment was Alternaria alternata. Penicillium chrysogenum was isolated only from non-disinfected grains. Presented results show that mechanical weed control treatments of appropriately adjusted intensity do not increase fungal colonization of barley grains in mixed culture with peas, as compared to the herbicidal control. The best variant of mechanical weed control for the cereal-legume mixture in terms of mycological quality of barley grain was one passage of spring-tine harrow at full tillering stage of barley. Mechanical weed control may be an alternative to herbicides in weed control in cereal-legume mixtures and may be particularly important for organic and integrated farming.
The aim of this study was to identify and quantify lignin transported from the River Vistula to the accumulation area in the Gdańsk Basin. Sediment samples collected along the Vistula mouth –Gdańsk Deep transect were analysed for lignin. Lignin was characterised by oxidative degradation, cupric oxide being chosen as the most suitable oxidising agent. The polar functional groups of the oxidation products were silylated and the derivatives analysed by capillary gas chromatography on fused capillary silica columns with flame ionisation detection. Lignin-derived oxidation products were quantified in the range from 3 to 20 μg g−1 dry wt. for phenolic acids and from 6 to 12 μg g−1 dry wt. for phenolic aldehydes. Differences in oxidation products contents are assigned to different lignin sources in the marine environment. The horizontal and vertical gradients of these compounds in the sediments of the Gdańsk Basin are documented. The results are discussed in terms of the origin and fate of organic matter in the Gdańsk Basin. The measured differences in quality and quantity of the identified oxidation products provide insight into diagenetic processes in the surface marine sediments.
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