Grain quality and N uptake of spring cereals as affected by nitrogen fertilization in northern conditions: a meta-analysis

Authors

• Elena Valkama MTT Agrifood Research Finland
• Tapio Salo MTT Agrifood Research Finland
• Martti Esala MTT Agrifood Research Finland
• Eila Turtola MTT Agrifood Research Finland

DOI: https://doi.org/10.23986/afsci.7448

Keywords:

nitrogen fertilization, protein content, 1000-seed weight, test weight, meta-analysis

Abstract

We reviewed quantitatively 40 Finnish field experiments related to the effect of nitrogen (N) fertilizer on the main parameters of grain quality and N uptake of spring cereals. The experiments were conducted on a wide range of mineral soils under varying growth conditions from the 1950s to the 1990s. Overall there was no statistically significant effect on 1000 grain weight and a slightly negative effect on grain test weight. Nitrogen fertilizer increased N uptake much more steeply in slightly acidic soils (SA, pH 5.8–6.9), located mostly in South Finland, than in moderately acidic soils (MA, pH 5.0–5.7), located in Central Finland. With increasing N rates, protein content increased to a larger extent in spring barley and oats than in spring wheat. In the light of the current trend to reduce N fertilizerapplication, the obtained regressions between N rates and the parameters of grain quality may be used to maintain yield quality at a desirable level, while optimizing N management.