Nutrient availability and yield formation.

Abstract

Available macronutrients present in the immediate vicinity of plant roots contribute only to a small degree to the total nutrient uptake of the plant. An important factor in the availability of a nutrient is therefore its mobility in the soil. The rate of translocation of a nutrient by diffusion or mass flow depends on its concentration in the soil solution, hence the nutrient level of the soil solution is of greater importance than the amounts of exchangeable or easily soluble plant nutrients in determining nutrient availability. Soil moisture and the volume of the root system also have an important effect on nutrient availability. In general, soil test methods based on the nutrient concentration of the soil solution give better correlations with plant growth than methods based on the pool of soluble and/or exchangeable nutrients. 43 references. (Abstract retrieved from CAB Abstracts by CABI’s permission)