Database Research Summaries2018 Tracking Cereal Rye Nitrogen Release through Soil Pools and Cash Crop Uptake
Research Focus
The focus of this project is to fill the knowledge gap that exist around the relationship of cover crops and N, cover crop selections before certain cash crops, and the feasibility of farmer N management changes such as N rates in the presence of cover crops.
Objectives
- Use 15N techniques to quantify the amount of cover crop N that is released to the soil
inorganic and organic pools. - Measure the amount of cover crop residue N that is utilized by the subsequent corn and
soybean crop.
Results
- On average cereal rye, produced 2,684 kg/ha of aboveground biomass and 50.5 kg N/ha of N uptake. Cereal biomass was refrigerated until it could be applied to correct micro-plots following corn and soybean planting
- Corn and soybeans were planted in micro-plots on 5/16/2017 at a rate of 32,000 seed/acre and 150,000 seed/acre respectively. Corn micro-plots received 30 lbs N/acre as starter at planting. A side-dress N application of 150 lbs. N/acre as urea was applied at the V5 growth stage.
- Reproductive growth stages tissue samples for both corn (R4) and soybean (R5) were collected on 8/23/2017. Reproductive tissue samples were separated into stover and grain samples. All tissue samples were dried and ground for analysis of total N and 15N stable isotope analysis. At each plant sampling date, 30cm soil samples were also collected for analysis.
- Corn and soybean are expected to mature in early October, and a third tissue sample will be collected at maturity to determine 15N content.
Importance
This will help farmers understand how cover crops can be managed to provide both economic and environmental benefits.
For more information about this research project, please visit the National Soybean Checkoff Research Database.
Funded in part by the soybean checkoff.
