Effects of nutrient (NPK) supply on faba bean response to elevated atmospheric CO2

Abstract

In greenhouse pot experiments, Vicia faba cv. Minica was grown at ambient (315 ppm) or increased CO2 concentrations (695 ppm) with sufficient or 90 or 70% of required N, P and K. Doubling of atmospheric CO2 resulted in a >100% increase in total yield. This CO2 effect disappeared rapidly with increasing N, P or K shortage. Doubling of atmospheric CO2 resulted in no change in minimum N concentration and no change or a slight decrease in minimum P concentration in crop residues.