Slow-release fertilizer to increase grain N content in spring wheat

Authors

• Ari Rajala MTT Agrifood Research Finland
• Pirjo Peltonen-Sainio MTT Agrifood Research Finland

DOI: https://doi.org/10.23986/afsci.8160

Keywords:

grain, nitrogen, protein, slow-release fertilizer, yield, wheat

Abstract

Low grain protein often restricts the use of grain lots for milling in Finland. Nitrogen availability during grain-filling may restrict grain protein accumulation, particularly in high yielding environments. Slow-release fertilizers could potentially sustain nitrogen availability during the grain-filling period. The aim of this study was to increase plant nitrogen uptake, grain yield and grain protein response of spring wheat cultivar ‘Amaretto’, using combinations of a regular and slow-release compound NPK fertilizer. Fertilizer treatment effects on grain yield was modest, however, slow-release fertilizer treatments lowered grain protein content as well as grain, straw and total plant N compared with control treatment. The total plant N was 10 to 27 kg ha^-1 lower following application of slow-release fertilizer. The results clearly indicate that the release of N by the slow-release fertilizer tested in this trial was too slow for cool Finnish growing conditions.