Variability of P Uptake by Plants

Abstract

Phosphorus (P) uptake affects the planning of P fertilisation of agricultural crops and subsequently the economic evaluation of farming practices and the quantification of agri-environmental burdens. The P uptake of plants is influenced by soil type, soil available P, availability of other essential nutrients, climate and weather conditions as well as by the nutrient use efficiency of the grown cultivar. Phosphorus coefficients are mainly derived from P fertiliser experiments, reflecting regional soil and weather conditions as well as farming practice. P coefficients commonly used for a single crop can vary substantially and hence rarely reflect the actual P uptake rates of crops. However, the main driving factor in P budgets is the yield level rather than the P concentration in plants. While it is difficult to determine a 'correct' P coefficient for all crops from which to calculate reliable agri-environmental indicators, it is important for farmers to be able to calculate their nutrient budgets as accurately as possible to avoid economic losses and environmental burdens.