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Dynamika wzrostu wybranych traw w rejonie gorskim

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The investigations were conducted in 1994-1995 in the mountain area situated 650 m a.s.l. Dynamic of growth and development of two grasses Arrhenatherum elatius and Dactylis glomerata was compared with the indigenous wild growing Holcus mollis. Every year the experiments lasted for 8 weeks, which included the period of growth from the beginning of grass vegetation till their cutting maturity. The date of the vegetation start was determined in the studies and the height of plants was assessed every two weeks, and dry mass yields and daily increase of those yields were determined. Arrhenatherum elatius was the species, which started its vegetation at the earliest date and was characterised with the greatest growth dynamic while Holcus mollis was placed the last. The biggest growths of dry mass were detected at the shooting stage. It was on an average twice bigger than in the tillering and earing stages and even between 3 and 5 times bigger than in the period after earing. At the shooting stage daily increase in Arrhenatherum elatius yields were on an average twice bigger than for Dactylis glomerata and Holcus mollis.
During two years of the investigations some morphological properties as well as the chemical composition of the one cultivar of the meadow clover (Trifolium pretense) and white clover (Trifolium repens) were compared with that of their ecotypes. The meadow clover was charac­terized in its first regrowth in cutting maturity and the white clover in the second regrowth in its pasture maturity. In both cultivars examined properties were characterized with the statistically higher parameters than in their ecotypes. The greatest differences between cultivars and ecotypes did not refer to the chemical composition.
Investigations were carried out in the years 1990-1991 in two regions: on plateau (310 m a.s.l) and in montains (640 m a.s.l.). The dynamics of increase of the dry matter yields and macroelements uptake were evaluated during the growth of first cut. It had been done for two varieties of orchard grass against a background of varying fertilization. It has been found that the rate of macroelements uptake considerable exceeded the increase of dry matter yields. The plants absorbed nitrogen the most intensively, next calcium and the slowest uptake was observed for phosphorus. Its rate of uptake was very close to the increase of dry matter yields.
A comparison of the farming value oi the three grasses (orchard grass, timothy grass and Italian ryegrass) cultivated in pure stands and in mixtures with red clover was made during,the years 1990 -1993. The experiment was carried out on a medium brown alluvial soil at Brzesko-Okocim, Italian ryegrass was the strongest limiting factor of the dynamic red clover growth, especially in the first year of the experiment, while timothy grass was the weakest limiting factor. During three veal's the grass/clover mixtures gave the dry matter yields similiar to the yields of grasses in monoculture cultivation which were fertilized every year at 150 kg N/ha rate. However, taking into account the crude protein yield, mixtures exceeded the grasses in pure stands about 30-40%. In the fourth year of utilisation the mixtures gave the lower yields as a result of clover lessening in the sward. Therefore, to ensure the yields similiar to the previous years, the mixtures demanded fertilizer N at 50-60 kg/ha. From simplified calculation it was clear, that the grass cultivation in pure stands which required nitrogen fertilization was 2.5-3 times more expensive than the grass/clover mixture cultivation. From the analyzed grasses, Italian ryegrass showed the lowest production potential in pure sowing as well as in grass/clover mixtures.
Badania przeprowadzono w latach 1999–2001 na pastwisku górskim z runią naturalną i zagospodarowaną przez podsiew koniczyną białą. Celem ich była ocena przydatności dwóch odmian i ekotypu koniczyny białej do podsiewu pastwiska. Przygotowując ruń do podsiewu zniszczono ją w 40–50% za pomocą glebogryzarki. Norma wysiewu nasion koniczyny wynosiła 5 kg×ha-1. W bada­niach oceniano utrzymywanie się koniczyny w runi oraz jej wpływ na plony suchej masy i białka ogółem. Najlepiej rozwinął się i utrzymywał w runi pastwiska wypasanego owcami ekotyp, zaś najsłabiej odmiana Podkowa. W trzecim roku udział ekotypu w plonie runi wynosił 26–38%, a odmiany Podkowa 18–28%. Plony suchej masy i białka ogółem z jednostki powierzchni były na ogół dodatnio skorelowane z udziałem koniczyny w plonie runi. Jednakże średnie plony suchej masy za 3 lata nie różniły się istotnie pomiędzy badanymi odmianami i ekotypem koniczyny białej. Natomiast z ekotypem zbierano średnio więcej białka ogółem o 77–140 kg×ha-1 niż z odmianami.
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