The potassium, sodium, magnesium, calcium and phosphate nutrition of sugarbeet (Beta vulgaris ) grown on soils containing incorporated straw

Between 1990 and 1992, a series of three experiments compared the effects of incorporating or removing straw from a total of five preceding cereal crops on the nutrient concentration, uptake and processing quality of sugarbeet. Incorporated straw increased K concentrations in tops and roots and increased total K uptake by c 40 kg ha(-1). Conversely, incorporated straw reduced Na concentrations and reduced total Na uptake by c 10 kg ha(-1). Straw incorporation had little effect on root processing quality, because whilst K impurities increased in the straw incorporated treatments, Na impurities were reduced. Generally, any effects of straw disposal method on concentration and uptake of phosphorus, calcium and magnesium were small. and of little agronomic or economic significance. In the absence of regular soil analysis it is recommended that when straw has been incorporated that K fertiliser rates for beet are reduced by c 20 kg ha(-1). This is less than the allowance made for cereals. Also, contrary to the current cereal recommendation, there was no evidence for reducing P inputs when straw had been incorporated.