Corn biomass, uptake and fractionation of soil phosphorus in five soils amended with organic wastes as P fertilizers

Abstract

Sustainable food production includes mitigating environmental pollution and avoiding unnecessary use of non-renewable mineral phosphate resources. Efficient phosphorus (P) utilization from organic wastes is crucial for alternative P sources to be adopted as fertilizers. There must be predictable plant responses in terms of P uptake and plant growth. An 18-week pot experiment was conducted to assess corn (Zea mays L.) plant growth, P uptake, soil test P and P fractionation in response to application of organic P fertilizer versus inorganic P fertilizer in five soils. Fertilizers were applied at a single P rate using: mono-ammonium phosphate, anaerobically digested dairy manure, composted chicken manure, vegetable compost and a no-P control. Five soils used varied in soil texture and pH. Corn biomass and tissue P concentrations were different among P fertilizers in two soils (Warden and Quincy), with greater shoot biomass for composted chicken manure and higher tissue P concentration for MAP. Plant dry biomass ranged from highest to lowest with fertilizer treatment as follows: composted chicken manure > AD dairy = MAP = no-P control = vegetable compost. Soil test P was higher in soils with any P fertilizer treatment versus the no-P control. The loosely bound and soluble P (2.7 mg P kg−1) accounted for the smallest pool of inorganic P fractions, followed by iron bound P (13.7 mg P kg−1), aluminum bound P (43.4 mg P kg−1) and reductant soluble P (67.9 mg P kg−1) while calcium bound P (584.6 mg P kg−1) represented the largest pool of inorganic P