Enzyme-based Test Kits for Phosphate

The goal of this proposal is to develop a recombinant form of the enzyme purine nucleoside phosphorylase (PNP) as the basis for development of simple, reliable, field-usable test kits for available phosphate (also called reactive, ortho, or soluble P). Enzyme-based methods for analytical chemistry have a number of advantages over wet chemistry and instrumental methods, including reduction of sample preparation time and decreased use of hazardous or toxic reagents. NECi, The Nitrate Elimination Co., Inc., has developed a series of enzyme-based nitrate test kits for agriculture. NECi's Ag-NTKs (nitrate test kits) and lab reagents are now in wide usage by farmers, Ag consultants, and major Ag feed/seed companies. These test kits combine ease of use with reliability of results. Here, we propose to apply the knowledge gained in development and implementation of Field Nitrate Test Kits to bring a green, sustainable field-usable Phosphate Test Kit to the market. Test kits for available P complement NECi's existing product line of enzyme-based test kits and reagents for nitrate, or available N. Application and management of N and P are key elements to successful production of agricultural products. Phosphate is an essential nutrient for plant productivity, but unlike nitrogenous fertilizers which can be manufactured, the supply of phosphate is finite and rapidly dwindling. Inappropriately applied phosphate nutrients leach from soils over time and enter the ground water. Excess phosphate is a major water quality problem, leading to eutrophication of ponds, lakes and coastal areas. Loss of recreational opportunities in rural areas has economic and social impacts: there's no fishing or swimming in impaired or algae-filled waters. NECi's products and R&D are based on clean manufacturing practices to develop recombinant enzymes for detection of compounds of environmental concern. Ag producers need better tools for management of N and P. These critical agricultural nutrients are coming under increased regulatory and cost pressures. Adoption of soil and water testing regimens into farm Best Management Practices (BMPs) will assist producers to improve management of soil and water quality, to save money by purchasing and applying the right amount of nutrients, and to stay in regulatory compliance. A test kit for soluble phosphate that provides reliable information on site, in the field, would be a useful tool to USDA Extension agents, farm managers, and technical service providers (TSPs). NECi's nitrate test kits are used by all of these groups, plus academic researchers in agriculture and environmental quality.