The influence of fertiliser N plus K on N, S and other mineral elements in perennial ryegrass at a range of sites

Abstract

Tn an agronomic experiment, perennial ryegrass was grown with four rates of fertiliser N + K at 21 sites in England and Wales. Herbage from two successive harvests at 14 of the sites has been examined for contents of N and S and of other mineral elements in relation to the nutrition of both the crop and ruminant animals. The highest rate of fertiliser application (125 kg N + 77.5 kg K/ha harvest) resulted in contents of total N greater than 4 % at five sites at the second harvest, but nitrate-N reached levels that might be toxic to livestock ( > 0.35 %) at only two sites. There was no evidence that supplies of S from soil and the atmosphere were inadequate for crop growth, or that the contents in the herbage were insufficient for ruminant animals, even though no S was supplied as feitiliser. On the contrary, in many samples, the content of S was so high as to constitute a potential hazard for ruminant animals through impairment of Cu availability. Values for the ratio total N : total S, which ranged from 3.2 to 15.6 : 1, generally increased with increasing rates of fertiliser. The concentrations of sulphate-S in the herbage were generally high and represented between 19 and 78 % of the total S. The content of Mg was only slightly affected by fertiliser N + K, but the ratio K : (Ca + Mg) increased markedly with increasing rates of fertiliser. At several sites the ratio exceeded 2.2 : 1, the value above which there is an increasing risk of hypomagnesaemia in ruminant animals. The sum of the concentrations of the cations C a + M g + K + N a in the herbage increased as the concentration of N increased, and there was a similar though less marked relationship between organic anions and total N in the herbage.

Effects of Biosolids-Derived Organomineral Fertilizers, Urea, and Biosolids Granules on Crop and Soil Established with Ryegrass (Lolium perenne L.)

“…Urea-based fertilizers can have similar efficiencies to ammonium nitrate when applications are conducted in spring but can be lower in summer (Watson et al 1990). In Y1, NUE recorded in urea-and OMF-treated grass were within the range reported in the literature (e.g., Whitehead, Jones, and Barnes 1978;Morrison, Jackson, and Sparrow 1980;, but exceeded those obtained in Y2 which were similar to values obtained by Williams, Rowarth, and Tregurtha (2000).…”

Robustness in the mineral supply from temporary grasslands

“…Management optimization of temporary grassland systems, which are only kept for a few years (Allen et al 2011) must take species traits and soil fertility into consideration (Whitehead et al, 1978;Hopkins et al, 1994).…”

“…However, many pasture plants supply other elements that influence the performance of those ingesting the herbage. Belesky et al (2001) investigated mineral composition in pure stand chicory and Whitehead et al (1978) in pure stand ryegrass but studies in mixtures have also been reported (Whitehead et al, 1983, Lawes & Gilbert, 1990, Hopkins et al, 1994. Hopkins et al (1994) described the variation in selected macro-and micro-mineral concentrations in Lolium perenne/Trifolium repens-dominated swards over seasons and over years (Hopkins et al, 1994).…”

“…In a review, Whitehead (2000) concluded that grasses in mixture with legumes often contain higher concentrations of P than the legumes and that white clover generally has higher concentrations of P than red clover and lucerne. More knowledge is needed regarding the variation in nutrient elements in individual species and species' organs in multi-species grassland (but see Whitehead et al 1978) and how they interact under changing nutrient supply level and mixtures composition as these are expected to be the dominant factors that challenge the buffering capacity of the systems.…”

Botanical composition, production and nutrient status of an originally Lolium perenne-dominant cut grass sward receiving long-term manure applications

“…It has been reported that increasing rates of N fertilizer to perennial ryegrass alters the ratios of N: S and of K :( Ca and Mg) (Whitehead et al 1978). Hopkins et al (1994) concluded that applied N reduced concentrations of Ca, Mn and S and increased those of Mg, Na and Zn, with no consistent effects on concentrations of K and Cu in herbage of perennial ryegrass.…”