The Manitoba Corn Initiative: Fertilization strategies for corn after canola
Crop Types
- Corn
Collaborating Locations
University of ManitobaBackground
This project will measure corn response to phosphorus and zinc fertilizer when corn is grown after canola. Research has shown mycorrhizal associations with corn are key for corn to acquire sufficient phosphorus and zinc. Therefore, to compensate for the deterioration in soil mycorrhizal populations after canola, corn growers may need to apply more P and Zn fertilizer to corn after canola.
Objectives
This project is a part of the larger Manitoba Corn Initiative - Corn Agronomy, fertility and agrometeorology. Overall objectives for the program include:
- Identify the best crops to grow prior to corn in a rotation
- Evaluate fertilization strategies for corn grown after canola
- Conduct an economic analysis of optimal crop rotations involving corn
- Identify optimum corn residue management strategies.
- Evaluate fertilization strategies for alternative tillage systems for corn production
- Evaluate the corn heat unit system for Manitoba
Summary
Preceding crop did not have any influence on mycorrhizal colonization of corn roots (total, arbuscular, hyphal, vesicular). However, application of P suppressed total and arbuscular colonization of corn roots by 5 and 4% respectively, relative to the unfertilized control. Side banded fertilizer increased early season biomass by up to 110% compared to the unfertilized control, with the largest increases in corn following canola. Zinc concentrations in plant tissue were highest for the unfertilized control and MESZn treatments, regardless of the preceding crop. Zinc uptake was significantly greater with application of starter fertilizer compared to the unfertilized control, especially in corn grown after canola. Silking date was advanced by 3-7 days with application of starter fertilizers. At harvest, all starter fertilizer treatments reduced grain moisture by 2-3% in corn following canola only, and there was a 10% yield increase in grain yield with the high rate of MAP compared to the control, regardless of preceding crop.
Key Takeaways
- Starter fertilizer benefits are greatest when corn Is planted after canola
- Starter fertilizer close to the seed allowed for excellent access to P
- Side-banded P at planting is agronomically superior to precision fall deep-banding for corn, keeping in mind that the fall deep band placement was deeper to most common fall applications