Improving nitrogen management in Québec grain corn

Description

Nitrogen is the main nutrient requirement for corn, and in 2017, 448,000 hectares of grain corn and feed corn were planted in Québec. Current recommendations suggest a nitrogen input of 120 to 170 kg per hectare (Parent and Gagné, 2010), but the current nitrogen dose is closer to 200 kg, and even as much as 240 kg in some cases. This seemingly excessive dose can be attributed to uncertainties about the influence of a number of factors, including climate, soil moisture and drainage, hybrid requirements, crop rotations, tillage, compaction, pH, and subsoil characteristics. Models have been developed based on various parameters to determine the optimal post-emergent nitrogen dose to apply. However, these models are not wholly accurate because they do not take soil health into account. The severity of a soil’s degradation will impact its water content, microbiology, and root development. Thus, it is critical to include this factor in nitrogen management models.

Objective(s)

• Evaluate the link between soil health and nitrogen fertilization requirements in corn.
• Assess corn nitrogen uptake under various conditions.
• Educate and encourage farmers and consultants with regard to nitrogen management.
• Improve the nitrogen management of grain corn crops in Québec.