Development of a soil N test for fertilizer requirements for wheat

• Published in: Journal of plant nutrition 2011-01, Vol.34 (5), p.762-777
• Main Authors: Miransari, M, Mackenzie, A.F
• Format: Article
• Language: English
• Subjects: Agronomy. Soil science and plant productions; and NH; Biological and medical sciences; Chemical, physicochemical, biochemical and biological properties; Economic plant physiology; fertilizer rates; fertilizer requirements; Fundamental and applied biological sciences. Psychology; grain yield; laboratory techniques; Metabolism; Metabolism. Physicochemical requirements; N test; nitrates; nitrogen fertilizers; Nutrition. Photosynthesis. Respiration. Metabolism; Organic matter; Physics, chemistry, biochemistry and biology of agricultural and forest soils; Plant physiology and development; pollution; soil; soil N mineralization; soil NO; soil sampling; Soil science; sowing; Triticum aestivum; wheat; wheat (Triticum aestivum L.) production
• ISSN: 0190-4167; 1532-4087; 1532-4087
• DOI: 10.1080/01904167.2011.540922

Optimal fertilizer nitrogen (N) rates result in economic yield levels and reduced pollution. A soil test for determining optimal fertilizer N rates for wheat has not been developed for Quebec, Canada, or many other parts of the world. Therefore, the objectives were to determine: 1) the relationship among soil nitrate (NO3−)-N, soil ammonium (NH4+)-N and N fertilizer on wheat yields; and 2) the soil sampling times and depths most highly correlated with yield response to soil NO3− -N and NH4+ -N. In a three year research work, wet and dried soil samples of 0- to 30- and 30- to 60-cm depths from 20 wheat fields that received four rates of N fertilizer at seeding and postseeding (plants 15 cm tall) were analyzed for NH4+ -N and NO3− -N using a quick-test (N-Trak) and a standard laboratory method. Wheat yield response to N fertilizer was limited, but strong to soil NO3− -N.