Analiza plonowania i zmian składu botanicznego runi łąkowej pod wpływem dokarmiania azotem dolistnie i doglebowo

Halina Jankowska-Huflejt

Instytut Melioracji i Użytków Zielonych, Zakład Łąk i Pastwisk w Falentach, ul. Hrabska 3, 05-090 Raszyn, Poland

Abstrakt

The aim of the conducted study was a comparison of the influence of foliar and soil fertilisation with urea on botanical changes of meadow sward. During the years 2001–2004 the study on 3-cut permanent meadow on mineral-boggy soil and on organic soil was conducted. The experiment established in randomized blocks design in four replications comprised 7 fertilisation treatments: 1. „0”, 2. PK, 3. PKN, 4. PKN + urea to soil, 5. PKN + foliar urea, 6. PKN + urea to soil + MgSO4, 7. PKN + urea foliar + MgSO₄. Every year the following were applied: P₂O₅ – 60 kg/ha, K₂O – 120 kg/ha, N – 70 kg/ha ammonium nitrate (as stable background for all combinations apart from „0” and PK) and 60 kg/ha urea (3 x 20 kg/ha), MgSO₄ - 9 kg/ha (3 x 3 kg/ha). Botanical composition of sward in I cut was evaluated by botanical-weight method. On both objects Alopecurus pratense and Poa pratensis L. dominated. The range of botanical composition changes of sward on mineral soil was small: participation of grasses decreased by 0–8%, instead on organic soil up to 40% on control (0) and by 25% on treatment 2. The space on mineral soil was replaced mainly by Taraxacum officinale F.H.Wigg., and on organic soil largely Ranunculus repens L., Taraxacum officinale F.H.Wigg. and Lychnis flos-cuculi L. The development of valuable grasses was stimulated more by urea applied to leaves than to soil.