Corn and soybean response to wastewater-recovered and other common phosphorus fertilizers

Abstract - Recycling phosphorus (P) from wastewaters could provide a sustainable source of P that could also protect surface water quality from P enrichment. Struvite (MgNH4PO4 · 6H2O) is a material that can be created from P-containing wastewater and has been shown to have agricultural fertilizer value. The objective of this study was to evaluate the effects of electrochemically precipitated struvite (ECST), chemically precipitated struvite (Crystal Green; CG), diammonium phosphate (DAP), monoammonium phosphate (MAP), rock phosphate (RP), and triple superphosphate (TSP) on corn (Zea mays L.) and soybean (Glycine max L.) response in a 79-day greenhouse pot study. Soybean aboveground dry matter (DM) and yield were unaffected by fertilizer-P treatments, but belowground, pod, and stem-leave tissue-P concentrations differed among fertilizer treatments. Total corn DM from ECST did not differ from that from RP and TSP, but was 1.2 times greater than that from CG. Belowground corn DM from ECST was 1.9 times greater than that from CG, TSP, and DAP. Corn belowground tissue P concentration from CG did not differ from that from DAP, TSP, and MAP, but was 1.4 times larger than that from ECST. Corn cob-plus-husk tissue P concentration from ECST was similar to that from MAP and DAP and was 1.2 times greater than that from CG. Results of this study not only provide information on the relatively new ECST material, but also substantiate the need for additional research on struvite as a potential alternative fertilizer-P source and the potential impact on sustainable food production and water quality preservation.