Zawartość azotu i podstawowych składników mineralnych w runi pastwiskowej w różnych latach jej użytkowania

Abstrakt

The aim of this paper was a comparison of the content of nitrogen and basic mineral components (P, K, Ca and Mg) in pasture sward in dependence on the period of utilization. The studies were carried out in 1996–2004 in a pasture experiment on peat-muck soil. Changes of the content of nutrients in the pasture sward were introduced in the first and third regrowth in two periods of utilization (years 1998–1999 and 2003–2004). Mixtures with different varieties of Lolium perenne were involved in research (Polish – ‘Anna’, ‘Arka’, ‘Maja’, ‘Rela’, ‘Solen’ and SZD-291 strain as well as Dutch – ‘Baristra’, ‘Barezane’ and ‘Barlano’). To estimate the chemical composition of fodder a sward of control mixture was chosen (without Lolium perenne) and mixtures with selected varieties of this species (‘Anna’, Maja’, ‘Solen’, ‘Baristra’, ‘Barezane’ and ‘Barlano’). The research stated appreciable differentiation of the most of studied components in dependence on regrowth as well as period of utilization. The content of nutrients was higher in the sward of third regrowth (except phosphorus), as well in the first and the second periods of utilization. Pasture fodder was characterized by a much by higher content of nitrogen in the second period of utilization (years 2003–2004). There was also found a higher content of potassium and calcium. However, the content of magnesium and phosphorus was not clearly diverse in dependence on the period of utilization. The content of the studied components oscillated in the range of optimum or higher values (mainly nitrogen in the second period of utilization).