With the objective of evaluating the effect of nitrogen doses (N) on the grain yield and the behavior of components involved in the N use efficiency of white oat (Avena sativa L.), a field experiment was conducted with four oat cultivars (CTC 5, UFRGS 15, UFRGS 19, and UPF 18), combined with four levels of N fertilization (0, 24, 48, and 73 kg ha-1). The experiment had a randomized block design with three replications, and was carried out on a Typic Hapludalf soil, with 26.7 g dm-3 of organic matter. The cultivars UFRGS 19 and UPF 18 presented a higher response potential to N fertilization in dry matter yield, N accumulation at flowering, N remobilization, and N fertilization efficiency compared with cultivars CTC 5 and UFRGS 15. The increase in N fertilization decreased the efficiency of N remobilization, uptake and fertilization efficiency; although it did not affect the N utilization efficiency, and increased the dry matter production, grain yield, and N accumulation at maturity in all evaluated cultivars.
Avena sativa L.; N uptake; N remobilization; N utilization; grain yield
