Effect and residual effect of N fertilisation on the N uptake of winter wheat in a long-term field experiment

Abstract

In wheat production, N fertilisation is one of the most effective agro-technical devices to increase yield and N concentration. In Hungary, fertiliser use, particularly that of N, has dropped dramatically in the last decade. The aim of this experiment was to study the direct and residual effect of N fertilisation on the grain yield and N uptake of winter wheat after 30 years of intensive N fertilisation. A long-term fertilisation experiment was set up on brown forest soil (Eutric Cambisol) with medium N status at Keszthely (Hungary) in 1965. In 1995, the plots were halved. From that year on, half of the plots no longer received N fertiliser, while the other half of the plots was fertilised with increasing N doses. Two years after the treatment modification, no residual effect of long-term intensive N fertilisation (10.44 t N/30 years) could be detected. Under the investigated site conditions, the omission of yearly N fertilisation led to low wheat yields and low N concentrations both in the grains and in the vegetative organs above the uppermost internode.