Effect of urea forms on ammonia volatilization, n recovery and yield of lowland rice in sandy and laterite soils

Abstract

An experiment was conducted to identify the best urea form which allows minimum N loss through ammonia volatilization but simultaneously ensuring good yield in the sandy and laterite soils of Kerala. The sulphur coated urea and urea mudball deep placement recorded minimum N loss through ammonia volatilization (2.85% and 5.29% respectively, of the applied N). However, application of urea supergranu lei n the reduced zone recorded the maximum grain yield and N recovery. Though the rate of ammonia volatilization was comparable between the two soils, yield was higher in laterite soil, irrespective of the treatments.