Polymer Fertilizer Coatings: Can They Increase Phosphorus Efficiency in Rice?.

A polymer coating of phosphate fertilizer was evaluated for rice yield response. Three rates of phosphate fertilizer, including polymer coated and non coated, were compared to an untreated check.  Soil and plant tissue samples were collected at two week intervals through out the growing season.  At seasons end grain was harvested and net yields determined. Net returns were calculated based on crop price and input costs. At the 28 P₂O₅ kgha^-1 rate the polymer coated treatments produced greater yields than equivalent non coated treatments.  At higher P₂O₅ rates both polymer coated and non coated treatments produced equivalent yields.  The 25 kgha^-1  P₂O₅ coated TSP treatment produced the greatest returns to producers.  Analysis of soil and tissue samples produced similar trends.