2023
Is There hope for Double Crops or Cover Crops in MN
Category:
Sustainable Production
Keywords:
DiseaseField management Pest
Parent Project:
This is the first year of this project.
Lead Principal Investigator:
Seth Naeve, University of Minnesota
Co-Principal Investigators:
Project Code:
10-15-48-23158
Contributing Organization (Checkoff):
Leveraged Funding (Non-Checkoff):
Bayer Crop Science has offered a small amount of in-kind support to connect the PIs with Minnesota producers experimenting with double cropping.
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Institution Funded:
Brief Project Summary:
In this project, researchers will assess the effect of soybean maturities and row spacing on yield for different intensification alternatives. Maturity ratings and row spacing combinations that maximize soybean yield will be evaluated for a double cropping system and with cover crops. Researchers will conduct field experiments in combination with simulation work to extrapolate results to different locations and future years. Goals include to quantify the impact of soybean management on yield for a sole crop, a cover crop, and double crops; and to assess the opportunities to successfully incorporate cover crop or double crop systems for different regions.
Key Beneficiaries:
#agronomists, #extension specialists, #farmers
Unique Keywords:
#agronomy, #cover crops, #cropping systems, #double crop
Information And Results
Project Summary

Cropping systems sustainable intensification refers to increased production per unit of land area without affecting system future capacities. It seeks to increase resource productivity by increasing the yield of a single crop or by intensifying crop sequence in the field. Since soybean has a reputation for yield plasticity, many agriculturalists have targeted soybean as a vehicle to incorporate ecosystem services through cover crops or additional economic returns through double cropping. Cover cropping is one of the most promising conservation practices with multiple benefits for production systems. Nevertheless, the adoption of cover crop/soybean sequence is still relatively low among MN farms due to cost or risk. Farmers require economically-viable solutions for production; therefore, further intensification by utilizing the double cropping system may provide another intensification alternative for Minnesota farmers. Unfortunately, nearly all the research effort has focused on the cover crop or the double crop with little research effort on the soybean piece of the pie. Broadly, the result is either disappointing soybean yields or highly erratic ones that range from very respectable to near failures. This research is intended to refocus attention on the primary cash crop – soybean – to identify combinations of cultural practices that minimize risk of yield loss. Once we have identified best management practices (BMPs) for the soybean portion of these intensification systems, we can truly assess the gains or losses in total soybean production that will result from their wide use. The questions we want to address are: What is the highest soybean yield that farmers can attain under these intensified systems after adjusting soybean management? and Is there a realistic opportunity to successfully incorporate some of these systems on our farms?

One of the main challenges for soybean in these intensification alternatives compared with the sole crop is the delay in planting date. In Minnesota, soybeans maintain nearly all of their yield potential when planted up until mid-May. Yield loss per day of delay increases progressively after that time. Soybean crops following cover crops frequently are planted after the end of this window due to planting delays or while waiting for biomass accumulation in the cover crop. In the case of soybean following winter barley, the planting date would be delayed until the end of June and even later than that following winter wheat. Normally-adapted varieties may find a mismatch between their most critical period for yield accrual and the shortened summer environment. Therefore, it is recommended that producers adjust varieties toward shorter maturities with lower risk, but correspondingly lower yield potentials.

On the other hand, planting delay exposes crops to conditions that hasten vegetative development. Delayed planting affects the capacity of the crop to reach full radiation interception (soil coverage) before the beginning of the critical stages (Monzon et al., 2021). This would be especially relevant in the case of early maturity varieties with an intrinsic shorter duration of the stage. Reduction in row spacing proved to be a useful management practice that increased the capacity of the crop to intercept radiation (Calviño et al., 2001). Thus, for those cropping systems that require a reduction in soybean maturity rate, we also expect that a reduction in the row spacing will increase soybean yield, biomass production, and yield stability across years.

Ultimately, we propose to assess the effect of soybean maturity rating and row spacing on soybean yield for different intensification alternatives. The question to answer is: Which are the maturity rating and row spacing combinations that maximize soybean yield for each cropping system (i.e., cover crop and double crops)? In order to answer this question, we propose to conduct field experiments in combination with simulation work to extrapolate our results to different locations and future years.

Project Objectives

(1) Quantify the impact of soybean management, including maturity rate and row spacing, on yield for different crop intensification alternatives: sole crop, cover crop, and double crops.
(2) Assess the realistic opportunities to successfully incorporate cover crop or double crop systems considering attainable yield and risk functions for different regions across MN.

Project Deliverables

(1) Data on soybean yield potential under different sustainable intensification alternatives (cover crops and double crops) in MN.
(2) Guidelines for soybean management for different intensification alternatives across MN.

Progress Of Work

Update:
- We conducted a controlled field experiment at St. Paul.
- Samples were processed and data analysis is in an advanced stage.
- We were able to estimate the potential yield and biomass for soybean in different cropping systems.
- We were able to estimate the impact of maturity and inter row spacing on soybean yield in different cropping systems .
- We are starting with the calibration and validation of the crop simulation models in order to extend these results to other field conditions.

View uploaded report PDF file

Update:
See attached

View uploaded report PDF file

Final Project Results

Updated May 31, 2024:

View uploaded report PDF file

Benefit To Soybean Farmers

(1) We will generate the information to conduct a realistic analysis of the opportunities for the adoption of sustainable intensification alternatives (cover crops and double crops) in MN. What soybean yield can we expect if we do our best?
(2) We will generate guidelines for soybean management for different intensification alternatives for different environments across MN. How to manage soybean for different intensification alternatives and environments?

The United Soybean Research Retention policy will display final reports with the project once completed but working files will be purged after three years. And financial information after seven years. All pertinent information is in the final report or if you want more information, please contact the project lead at your state soybean organization or principal investigator listed on the project.