Bread wheat (Triticum aestivum L.) produced in areas of higher rainfall, such as eastern Canada, are often low in protein. Our objective was to determine if N management could be used as a way to produce bread quality wheat in eastern Canada. An experiment was conducted for 2 yr at two Quebec sites. The effects of N fertilizer level and timing on grain yield, yield components, and lodging level of four hard red spring wheat cultivars with breadmaking potential were investigated. The soil type was Ste‐Rosalie clay (fine, non‐acid, frigid, typic Humaquept). The experiment was a four (cultivars) × four (N level) × two (N timing) factorial. Cultivars were Columbus, Katepwa, Max, and Hege 155‐85. In both years, 0, 60, 120, and 180 kg N ha‐1 were applied at seeding or 60% at seeding and 40% at anthesis. Hege 155‐85 had the highest gram yield, responded most to N fertilizer addition, and was the most resistant to lodging. Differences in N management effects and cultivar responses were observed among the four site‐years. Grain yield, plant height, lodging, tillers per square meter, spikes per square meter and kernels per spike increased with increasing N fertility. When compared with application of all the fertilizer N at seeding, split application of N fertilizer (60% at seeding, 40% at heading) had little effect on yield (no effect at three site‐years, small reduction at the fourth), reduced the risk of lodging at one site, caused a reduction in the number of tillers per square meter and spikes per square meter at one site‐year, caused an increase in 1000‐kernel weight at two site‐years, and caused an increase in test weight at three site‐years. Gram yield increases due to greater N application were largely due to increases in kernels per spike and tillers per square meter. The correct combination of N application level and timing of N application can increase yields and reduce the risk of lodging. However, under these experimental conditions, the most important management decision is the choice of cultivar.

The production of bread‐quality wheat (Triticum aestivum L.) in eastern Canada might be possible through correct fertilizer management. Field experiments were conducted for 2 yr at each of two sites in Québec. The influence of N fertilizer level and timing on breadmaking quality and grain ash of four hard red spring wheat cultivars (Columbus, Katepwa, Max and Hege 155‐85) known to have potential as bread wheat was investigated. The soil types were fine, mixed, non‐acid, frigid Humaquept at Ste‐Anne‐de‐Bellevue and typic, non‐acid, frigid Humaquept at Ste‐Rosalie. Four rates of N (0, 60, 120, and 180 kg N ha−1) were applied at seeding time or 60% at seeding and 40% at anthesis, resulting in a 4 × 4 × 2 factorial experiment with four replications. Increasing N reduced gram and flour ash concentrations and increased flour protein concentration, Hagberg falling number and flour absorption of water. Splitting the N application increased flour protein concentration and bread loaf volume. Cultivar by N level interactions often occurred for farinograph variables. Farinograph readings for Max and Hege 155‐85 were unproved with N fertilizer addition, but this was generally not the case for Katepwa and Columbus. In general, all cultivars tested could produce flour suitable for bread wheat production in eastern Canada but the N management required for this varied with cultivar. Despite its high grain and flour yield, Hege 155‐85 may not be economical to produce because high N fertilizer applications are required to achieve the appropriate protein concentrations and flour might have to be supplemented with gluten to achieve the required protein concentration.

Information regarding the relationships between soil properties and the economic optimum N rate for crop yield is needed to ensure profitable use of N fertilizer. This study was conducted in 2007 and 2008 at 62 field sites in Québec (eastern Canada) to assess corn (Zea mays L.) response to N fertilizer, to calculate the economically optimum nitrogen rate (EONR) and corn yield (EOY), and to relate these two parameters with soil and crop‐based parameters. Yield response to N fertilizer rates (0–250 kg N ha−1) at each site was fitted to a linear, quadratic, or quadratic‐plus‐plateau model. The EONR and yield (EOY) were related to 12 soil and crop‐based parameters, and corn heat units (CHU). The quadratic‐plus‐plateau model best described the yield‐fertilizer relationship at 43 of the 62 field sites. The values of EOY varied from 7.4 to 13.3 Mg ha−1 in 2007 and from 5.2 to 11.2 Mg ha−1 in 2008, while EONR was between 73 and 235 kg N ha−1 in 2007 and from 48 to 200 kg N ha−1 in 2008. Correlation and principal component analysis showed that dissolved nitrogen (DNc) and dissolved carbon (DOCc) extracted with cold water and pre‐sidedress nitrate analyzed using nitrate test strips (PSNTts) were significantly and negatively related to EONR. In both years, PSNTts was consistently related to EONR, and CHU with EOY. While it remains challenging to predict EONR due to site‐specific variability and fluctuations in growing conditions, the PSNTts test shows promise in predicting the EONR for corn production in Québec.

Nitrogen management for production of bread quality wheat (Triticum aestivum L.) in eastern Canada has received little research attention. An experiment was conducted for 2 years at each of two sites in Québec to study the effect of level and timing of nitrogen (N) fertilizer application on grain protein concentration, protein content per seed, non‐protein seed dry matter, grain protein yield and nitrogen harvest index (portion of plant N in the grain) of four hard red spring wheat cultivars known to have potential as bread wheats in eastern Canada. The soil types were Bearbroock clay (fine, mixed, non‐acid, frigid, Humaquept) and Ste‐Rosalie clay (typic, non‐acid, frigid, Humaquept). The experiment was a 4 × 4 × 2 factorial. Four cultivars were used: Columbus, Katepwa, Max and Hege 155–85. In both years 0, 60, 120 and 180 kg Nha−1 were applied either all at seeding or 60 % at seeding and 40 % at heading. Grain protein concentration and grain protein yield increased consistently with increasing N fertilizer and with split N application. Nitrogen harvest index was not increased by increasing applications of N fertilizer. Protein content per seed was more critical in determining grain protein concentration than non‐protein seed dry matter content. The western Canadian cultivars Columbus and Katepwa generally had greater grain protein concentration than the European cultivars Max and Hege 155–85, With reasonable N fertility the grain protein concentration of spring wheats grown in eastern Canada are sufficient for bread production.