Grain yield and nitrogen use efficiency by rice (var. Jaya) was more when urea supergranules (USG) were deep placed as compared with urea super granules broadcast and incorporated and prilled urea applied in three splits in an Aquic Hapludall. The grain yield showed a quadratic relationship with nitrogen levels. The pH, total alkalinity and ammonium concentration of flood water was maximum in prilled urea splits followed by USG broad cast and incorporated and USG deep placed, thereby suggesting higher potential losses through ammonia volatilization in the former case as compared with the latter two.
Nitrogen use efficiency, fertilizer placement, flood water parameters, rice
