Effect of buckwheat ( Fagopyrum esculentum) on soil-phosphorus availability and organic acids.

As a cover crop, buckwheat ( Fagopyrum esculentum) may increase soil-P availability. Buckwheat was grown in low-P and P-fertilized field plots, and organic anions were measured in rhizosphere soil. Soil-P availability was not affected by buckwheat, but the concentration of rhizosphere tartrate2- was significantly higher ( p < 0.005) in low-P vs. P-fertilized plots. This suggests that organic-anion root exudation may have a role in buckwheat-rhizosphere P dynamics. [ABSTRACT FROM AUTHOR]