Fertilization with nitrogen and potassium on pastures in temperate areas

Abstract

Fertilizer application enable producers to influence pasture production. The effect of N fertilization on grass production and leguminous plant content of pasture and strategic N application has received much attention. Changing agricultural policies suggest that chemical fertilizer inputs may be diminished and that alternative sources of nutrients are desired. The aim of this study was to evaluate the effect of N and K fertilization on production, botanical composition, and forage mineral composition to gain some insight into what influence changing fertilization practices would have on pasture productivity. Three K and 3 N application rates were applied in a factorial design on a white clover (Trifolium repens L.) perennial ryegrass (Lolium perenne L.) sward. Potassium and nitrogen application increased herbage production and had differential influences on botanical composition. Nitrogen decreased clover content in the pasture, whereas K increased the proportion and production of white clover. The effects of K application appeared later in the experiment than those associated with N. We concluded that K is very important for development and maintenance of white clover in pasture, which increases herbage and protein production. Nitrogen was associated with lesser amounts of N, P, K, and Mg in pasture, because of lesser amounts of clover in the sward. Changing fertilization practices will have definite influences on sward composition and pasture productivity. Any interpretation of pasture mineral content should take botanical composition changes into account.

The diagnosis and correction of potassium deficiency in New Zealand pastoral soils: a review

“…This was not due to a decline in the soil QTK level on the control plots, and has been observed elsewhere in legume-based pastures (Spencer & Govaars 1982;. Furthermore, there is much other evidence indicating that the clover component of mixed pastures is the first to respond to K application on K-deficient soils (Meissner & Clarke 1979;Spencer & Govaars 1982;Ledgard et al 1997;Bolland et al 2002;Mosquera-Losada et al 2004;Gillingham & Gray 2007). This is most likely due to legumes' higher requirement for soil K than grasses (Spenser & Govaars 1982;Bolland et al 2002).…”

Mineral concentrations in herbage and soil in a Pinus radiata silvopastoral system in north‐west Spain after sewage sludge and lime application

“…The increase in soil N content (both ammonium and nitrate) obtained after sewage sludge application led to an increase in CP concentrations in herbage. Crude protein concentrations obtained after sewage sludge application were similar to those reported in previous studies in temperate regions (90–250 g kg −1 DM; Mosquera‐Losada et al. , 2004).…”

“…In all cases, the values were within the lower part of the normal range established by Grace (1983a) for temperate pastures. Concentrations of K in herbage (1·3–19 g kg −1 DM) were similar to or lower than the range of values reported by Whitehead (1995) (15–30 g kg −1 DM) for L. perenne and T. repens , but lower than those reported by Mosquera‐Losada et al. (2004) (11·2–26·4 g kg −1 DM) for the same species in agricultural soils.…”

“…(1986a) after lime application and by Mosquera‐Losada et al. (2002b) in forest soils, but lower than those reported by Mosquera‐Losada et al. (2004) in agricultural soils after application of mineral fertilizer.…”

“…Maximum CP concentrations and treatment differences were seen in spring and are in line with the more marked differences in soil nitrate content and the better growing conditions. A second increase in CP concentration in forage was seen in the autumn in the first year of the study; such an increase is normal for lowland pastures in Galicia (Mosquera‐Losada et al. , 2004), but it was not detected in the second and third year, probably due to the lower temperatures, which limited herbage growth in these periods and, therefore, limited the responses to the different treatments.…”