Soil Microbial Response to Seven Different Organic Transition Strategies

Project Overview

GNC12-154
Project Type: Graduate Student
Funds awarded in 2012: $9,920.00
Projected End Date: 12/31/2015
Grant Recipient: University of Missouri
Region: North Central
State: Missouri
Graduate Student:
Faculty Advisor:
Dr. Randall Miles
University of Missouri

Annual Reports

Commodities

  • Agronomic: corn, sorghum (milo), soybeans, wheat

Practices

  • Crop Production: conservation tillage
  • Production Systems: transitioning to organic
  • Soil Management: green manures, organic matter, soil analysis, soil microbiology, soil quality/health

    Proposal abstract:

    Our agricultural soils are being depleted through the use of tillage, chemical fertilizers and lack of ground cover. One way to improve soil health is through organic cropping practices. The goal of this project is to track soil microbial changes in response to seven different cropping strategies for farmers transitioning into organic grain production. Outcomes include determination of best soil-building practices for transitioning organic farmers and transfer of basic information on organic grain crop production to Extension educators and NRCS personnel. The seven cropping strategies are all three-year rotations and include systems that 1) utilize only soil-building cover crops, 2) focus on soil building for two years and a cash crop the third year, 3) a no-till organic system with a corn/soybean/wheat rotation and 4) no-till with grain sorghum instead of corn, 5) a conventional till system with corn/soybean/wheat rotation, 6) conventional till with sorghum replacing corn, and 7) a conventional till system that utilizes cover crops for a full year and follows with two years of a cash crop. In addition, three organic farmers will choose two of these strategies for on-farm trials. A randomized complete block design of four replications will be utilized. Soil microbial activity and diversity will be measured using enzyme assay and phospholipid fatty acid analysis. Outputs include one scientific article, a University Extension publication, news media releases, postings on websites and eOrganic and presentations at MU field days, an NRCS in-service training, the Missouri Organic Association (MOA) conference and at an MU organic grower’s field day. The evaluation plan includes an annual survey to Missouri organic grain producers and a link to a web-based survey at MU and MOA websites.

    Project objectives from proposal:

    Project Outcomes. The goal of this project is to track soil microbial changes in response to seven different tillage and cropping strategies for farmers transitioning into organic grain production. Short term outcomes of this project include determination of cropping system interaction with soil microorganisms and increased knowledge of soil building strategies for organic farmers during the transition phase. This information will be transferred to farmers via web-based learning and producer’s field days. Intermediate outcomes include adoption of best soil management practices by transitioning or organic farmers and transfer of basic information on organic grain crop production to Extension educators and Natural Resources Conservation Service (NRCS) personnel, and inclusion of these practices into NRCS recommendations. Longer term outcomes might include adoption of these practices into NRCS cost share programs and their adoption by conventional farmers who see soil building as a necessary sustainability practice.
    Context, Background, and Rationale. America’s soils are being depleted through the overuse of tillage and chemical fertilizers and lack of ground cover. One way to regain lost soil organic matter and rebuild soil microbial populations is through organic cropping. It is fairly well established that organic practices lead to increased soil microbial diversity and activity, but different organic strategies can lead to different results. Bacteria, actinomycetes and fungus all have different effects on crop health and yield, so it is important to know how different crop systems affect the ratios and diversity of microorganisms in the soil. Improving soil health is never more vital than the three year transitional period from conventional to organic row cropping. We propose to experiment with a wide range of possible cropping systems to provide information on best management practices for soil building during this period. The overall goal of this research project is to improve the competitiveness of transitional and organic grain crop producers by documenting critical information on cropping systems that will maintain or increase productivity and build soil health. This will help ensure a more secure future and enhanced quality of life for rural communities and will lead to improvement of our limited soil resources. Specific goals of this project are:
    • Compare seven different rotational and tillage systems for transitioning into organic production and determine the effect of each strategy on soil microbial activity and diversity.
    • Convey these results to organic and transitioning farmers
    • Utilize project data to train University Extension and NRCS personnel and create outreach programs for organic producers in Missouri.
    The seven cropping strategies are all three-year rotations and all have continual ground cover. The first system utilizes only soil building cover crops and the other six treatments will be compared to this system as a strategy for maximum soil building vs. practices that provide an income during the transition years. The other six systems include one that focuses on soil building for two years and a cash crop the third year, a no-till organic system with a corn/soybean/wheat rotation and a no-till with grain sorghum instead of corn, two conventional till systems that follow the same rotations as the two no-till, and one conventional till system that utilizes cover crops for a full year and follows with two years of a cash crop.

    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.