Artigo
Rates of urea with or without urease inhibitor for topdressing wheat
Autor
Rocha, Valterley Soares
Espindula, Marcelo Curitiba
Souza, Moacil Alves de
Campanharo, Marcela
Paula, Guilherme de Sousa
Institución
Resumen
O artigo não contém o resumo em português. The urease inhibitor NBPT(N-(n-butyl) thiophosphoric triamide) is a management alternative to increase urea efficiency in topdressing because it reduces NH3 volatilization. The objective of this study was to evaluate N recovery and yield performance of wheat (Triticum aestivum L.) 'BRS 254' fertilized with different urea or urea + NBPT rates in topdressing. The experiment was conducted from May to September 2007 in Vicosa, Minas Gerais, Brazil. Treatments followed a 5 x 2 + 1 factorial design consisting of five N fertilizer rates (30, 60, 90, 120, and 150 kg ha^-1) as urea or urea + NBPT (Agrotain®) applied as topdressing and a control without N. The experiment was a randomized complete block design with four replicates. Adding NBPT to urea resulted in better N utilization by wheat plants. The 100 kg N ha^-1 topdressing rate provided the best apparent N recovery by wheat plants, whereas 90 kg ha^-1 provided the best N use efficiency.