The urease inhibitor NBPT(N-(n-butyl) thiophosphoric triamide) is a management alternative to increase urea efficiency
in topdressing because it reduces NH
3 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 Viçosa, Minas Gerais, Brazil. Treatments followed a
5 × 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.