Fate and efficiency of nitrogen fertilizers applied to wetland rice. II. Punjab, India

摘要: Two modified urea products (urea supergranules [USG] and sulfur-coated [SCU]) were compared with conventional ammonium sulfate as sources of nitrogen (N), applied at 58 kg N ha−1 116 ha−1, for lowland rice grown in an alkaline soil low organic matter light texture (Typic Ustipsamment) having a water percolation rate 109 mm day−1. The SCU USG transplanting, the whole dose was15N-labeled; was prepared laboratory not completely representative commercial SCU. broadcast incorporated, whereas point-placed depth 7–8 cm. applications split: two-thirds incorporated one-third panicle initiation. All fertilizers except last labeled with15N so that fertilizer-N balance flowering maturity stages crop could be constructed magnitude loss assessed.