Updating National Nitrogen Fertiliser Recommendations for Cereals and Oilseed Rape

Keywords: Nitrogen, fertiliser, wheat, barley, oilseed rape, RB209.

This paper reviews experimental data describing the effect of nitrogen (N) fertiliser rate and timing on the yield and grain N concentration of winter oilseed rape and all major cereals (winter wheat, winter barley, winter oats, winter triticale and spring barley). The main aim of the project, funded by the UK Agricultural levy board (Agriculture and Horticulture Development Board (AHDB)), was to provide robust scientific evidence for updating the ‘Fertiliser Manual (RB209)’. Experimental datasets including over 1,600 N response curves were analysed from both publicly funded and industry funded projects.

Key areas of the national fertiliser recommendations that were reviewed included, but were not limited to; optimum N rates for specific soil types, the relationship between N fertiliser requirement and yield potential, optimum N timing for winter barley and oilseed rape, and optimum N timing and rate for achieving specific grain N concentrations of spring and winter barley. Implications of the proposed updates of the N recommendations for crop yield, grain quality, gross margin over N costs, the risk of pollution and future research priorities are briefly discussed.

S.M. Clarke and P. Newell-Price, RSK ADAS Ltd. Gleadthorpe, Meden Vale, Mansfield, NG20 9PD, UK.

S. Roques, RSK ADAS Ltd. Boxworth, Battlegate Road, Boxworth, Cambridge, CB23 4NN, UK.

P.M. Berry, RSK ADAS Ltd. High Mowthorpe, Duggleby, Malton, N. Yorks, YO17 8BP, UK.

S.M. Knight, NIAB, Huntingdon Road, Cambridge, CB3 0LE, UK.

20 pages, 8 figures, 3 tables, 23 references