01939naa a2200397 a 450000100080000000500110000800800410001910000190006024501270007926000090020652009130021565000220112865000150115065000140116565000090117965000090118865000100119765000160120765000290122365000130125265000130126565000110127865000140128965000150130365000090131865000110132765000100133865300150134865300160136365300170137965300110139665300120140765300210141970000230144077300780146317892722013-09-23       1982    bl ---       0--  u    #d1 aLEDGARD, S. F.  aEffects of nitrogen fertiliser and urine on pasture performance and the influence of soil phosphorus and potassium status.  c1982  aPasture responses to 4 levels of urea fertiliser and a cow urine treatment were examined at 3 phosphorus (P) and 2 potassium (K) levels in soil. Urea increased reygrass growth and subsequently decreased clover growth. Nitrogen (N) fixation by clovers was reduced initially because of substitution by uptake of mineral N from the soil, and subsequently because of reduced clover yields. Plant recovery of fertiliser N was high, an estimated 93% at 25 kg/ha of N, whereas recovery of urine-N was only 30%. There was no interaction between N and P or K affecting total herbage yield, clover yield, N fixation, chemical composition of herbage, or N recovery by herbage. There was an increase in total yield from urine at the high soil P level and a decrease in total yield at the high soil K level. The results suggest there is no requirement for extra P or K in the soil when low rates of N fertiliser are used.  anitrogen fixation  aphosphorus  apotassium  asoil  aurea  aurine  aCrescimento  aFixação de Nitrogênio  aFósforo  aPastagem  aPlanta  aPotássio  aProdução  aSolo  aUréia  aUrina  aFeed crops  aFertilisers  aFertilizacao  aGrowth  aPasture  aPlant production1 aSAUNDERS, W. M. H.  tNew Zealand Journal of Agricultural Researchgv.25, n.4, p.541-547, 1982.