Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 10

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
There was noticed the best pasture surface cover in the year of experiment establishment. Turfness of pasture with Poa pratensis in the sward was better than in pasture with Lolium perenne content, except the turfness in sowing year. That time, fast growing perennial ryegrass was a predominant species in the sward. High soil moisture was conductive to expansion of Lolium perenne. However, observations carried out in autumn confirmed higher values of pasture surface cover. It was a result of progressive development of Poa pratensis and high regenerating ability of Lolium perenne. Grass-clover mixtures in both experiments covered pasture surface better than grass mixtures. There were noticed significant differences between turfness in grass and grass-clover treatments with Anda and Alice white clover cultivars, under Poa pratensis experiment and in relation to treatments with Armena and Alice white clover cultivars under Lolium perenne pasture. Content of white clover in pasture cover during spring and autumn was not as high as in sown mixtures, but amount of this species in the sward increased during warmer part of vegetative season. Presence of white clover in the sward ensured better turfness productivity of pasture. Results of carried out studies confirmed direct proportional relationship between pasture surface cover and productivity of pasture. Productivity of grass-clover sward was similar to productivity of grass sward, fertilized with nitrogen in dose of 80 kg ha⁻¹. Higher nitrogen fertilization was detrimental to pasture cover and its productivity under postboggy habitat.
The grazing studies were conducted in two experiments established in 1996 and located on peat-muck soil. A randomised block design with four replications was used. The investigations with two sward types in every trial aimed to compare the maintenance of Lolium perenne and Poa pratensis in the pasture under postboggy habitat. The mentioned species were the main grass components in grass-clover mixtures, fertilized with 40 kg ha⁻¹ N and also in grass mixtures, fertilised with 40, 80 and 120 kg ha⁻¹ N. Seven cultivars or Trifolium repens were included to grass mixtures. As the white clover cultivar was never significant then the results from the seven grass-clover treatments were pooled in the data presentation. The pasture swards were grazed rotationally with Limousine cattle four times a grazing season. Samples of the herbage were analysed for the botanical composition by manual separation and expressed on a weight basis. Lolium perenne grew well in postboggy habitat and became rapidly predominant species in grass and grass-clover sward. Low resistance to frost in December and January in 1996 to 1997 was the most important reason of Lolium perenne content variation in the pasture sward. However, during the vegetative season of 1997 proceeded good regeneration of this species. Development of Poa pratensis in the sward also depended on climatic conditions. High rainfalls in late autumn of 1996 and 1997 influenced negatively stability of this specics in the grass community. Presence of Trifolium repens in the pasture sward affected beneficially the wintering of Lolium perenne and favoured the expansion of Poo pratensis.
Assessment of the effect of sown mixtures composition on floristic composition and value of pasture sward was a purpose of the studies. White clover maintained the best in the sward. There were confirmed higher seasonal changes of white clover, bird trefoil, black medic and alfalfa content in the pasture sward on mineral soil than on peat-mursh soil. Introduction of some perennial ryegrass cultivars ensured predomination of this species in the sward even under peat-mursh soil conditions.
Określono zawartości B, Cu, Zn, Fe i Mn w wybranych gatunkach traw i roślin motylkowatych oraz chwastach dwuliściennych z pierwszego odrostu nowo założonych doświadczeń pastwiskowych. Stężenie mikroelementów w runi pastwiskowej zależało od warunków glebowych i gatunku roślin. Rośliny pastwiskowe zawierały więcej Cu i mniej Zn w warunkach malejącej kwasowości gleby. Najmniej Cu zawierały Phleum pratense i Medicago sativa, a najmniej Zn - Trifolium repens. Najbardziej niewłaściwe proporcje Fe/Mn stwierdzono w Dactylis glomerala i chwastach dwuliściennych, pochodzących z gleby torfowo-murszowej. Wprowadzenie roślin motylkowatych do runi pastwiskowej pozwoliło uzupełnić niedobory B i Cu, a tym samym poprawić biologiczną wartość paszy.
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.