『Abstract
』A 3-year field study was conducted in southwestern Manitoba,
Canada, to evaluate the effect of nitrogen (N) fertilizer management
and seeding data on end-use quality of wheat, in terms of protein
concentration, milling and baking characteristics and grain Fe
and Zn concentrations. In each year, experiments were established
on two different sites representing either fine sandy loam (FSL)
or clay loam (CL) soil types. Treatments consisted of a factorial
combination of two seeding dates and ten N fertilizer managements,
comprised of control (no N fertilization), base N fertilization
(60 kg ha-1 as urea), and base plus supplemental 15
kg ha-1 increments of N applied as urea, urea ammonium
nitrate (UAN) or ammonium nitrate (AN) at various stages. Grain
yield and all and all quality traits differed significantly among
six soil type by year combinations, suggesting a strongly environmental
influence. Delaying seeding date consistently decreased grain
yield on the CL soils but not on the FSL soils, indicating that
the optimal seeding date may strongly depend on soil and climatic
factors. Application of N did not improve grain yield in most
soil type-year combinations, due to a relatively high soil background
N and climate conditions. Delaying seeding date resulted in a
considerable reduction in grain concentrations of Fe and Zn, protein
in grain and flour, as well as the measured milling and baking
quality traits. Compared to the non-fertilized control, N fertilization
increased protein concentration in grain and flour in most soil
type-year combinations. However, N fertilization did not consistently
affect grain Fe and Zn, or other end-use quality traits. The source
and timing of N fertilizer did not consistently affect any trait.
The lack of consistent effects of N fertilization on milling and
baking quality may be due to the relatively high protein concentration
of the grain. Therefore, of the factors evaluated, seeding date
had the greatest influence on the end-use quality of spring wheat
and therefore should be carefully considered when making recommendations.
Keywords: Iron; Nitrogen fertilization; Protein; Seeding date;
Zinc; Wheat』
1. Introduction
2. Material and methods
2.1. Site and growing seasons
2.2. Treatments and experimental design
2.3. Sampling and analysis
2.4. Data analysis
3. Results
3.1. Climate
3.2. Grain yield
3.3. Grain and flour protein concentration
3.4. Grain concentrations of Fe and Zn
3.5. Bread-making quality
3.6. Correlation coefficients between measured parameters
4. Discussion
5. Conclusion
Acknowledgements
References