Weeks 3 and 4 Schedule and Objectives

During this module, we will discuss yield plateaus and gaps on a global scale, as well as techniques for managing pests and cover crops.

Global Food Challenges & Solutions, Pest Management

Week 3: World Cereal Yield Plateaus and Yield Gaps, Alternative Food Species [Feb 8-14]

Week 4: Pests and Cover Crops Management [Feb 15-21]

Learning Objectives

Discuss the options for increasing food production when major cereals have reached genetic plateaus in key production regions in the U.S. In what ways do we face this same issue in Rwandan agriculture?
How can farmers in Nebraska manage cereals to narrow the ‘yield gap’ in our current agricultural systems? What about in Rwanda? What strategies other than growing current cereals can increase food production?
What strategies are useful for managing weeds, insects, pathogens and other pests as alternatives to chemical pesticides? What options do we have when regulations remove detrimental current pesticides?
What are the multiple roles of cover crops in farming systems, in terms of pest management, grazing potential, and providing soil nutrients to maintain fertility?

- Please explore the Global Yield Gap Atlas website (alternate link here), a project that measures the yield gap and yield stability across the globe. Write a response to the prompt on Yellowdig. 10 points, Due Feb 7.
  - Read the one-page summary of the Global Yield Gap Atlas project here (alternate link here).
  - Explore the interactive tool here. If the tool is down, please read this brief article about the project and its goals.

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- - - Pay special attention to the Yield gap indicator (red box above). What is a yield gap? What might contribute to the differences in yield gaps in different countries around the world (think about social, economic, and environmental factors)? Why is it important to understand the concept of yield gaps and how do they connect to other material we've covered so far?
    - Optional reading: Grassini, P., Eskridge, K. & Cassman, K. Distinguishing between yield advances and yield plateaus in historical crop production trends. Nat Commun 4, 2918 (2013). https://doi.org/10.1038/ncomms3918
- On Friday, or ahead of 10:00 PM Saturday, write a post on Yellowdig about what you have learned this week, 10 points, Due Feb. 13 at 10 PM.
- Be sure to read several of the Yellowdig posts of your class members and respond to any that pique your interest.

- Read Phatak and Diaz-Perez. Managing Pests with Cover Crops. Managing Cover Crops Profitably. SARE https://www.sare.org/publications/managing-cover-crops-profitably/managing-pests and Liebman and Davis. 2009. Managing Weeds in Organic Farming Systems: an Ecological Approach. In Francis, editor. Amer. Soc. Agronomy. https://pdfs.semanticscholar.org/27e7/1ddaebb50cc1320dad25a5f5f8c4a79381b1.pdf. Write a response to the prompt on Yellowdig. 10 points, due Sunday, Feb 14, 10:00 PM.
- On Friday, or ahead of 10:00 PM Saturday, write a post on Yellowdig about what you have learned this week, 10 points, Due Feb. 20 at 10 PM,
- Be sure to read several of the Yellowdig posts of your class members and respond to any that pique your interest.
- Notice that Yellowdig cycles the period for postings on Saturday at 10 PM. Your score will drop to 0 to reflect that you have not posted yet for the new week, but your points do not go away.

PowerPoints and Lecture Recordings

The PowerPoint presentations and lecture recordings will be posted here after classes.

Feb. 12 Recording (note, this class period was largely small group discussion)

Feb. 17 PowerPoint, recording, (link to Cover Crop Species Selector Tool mentioned in lecture: https://covercrop.tools/species-selector)