Domesticating Intermediate Wheatgrass for Sustainable Grain Production

Domesticating Intermediate Wheatgrass for Sustainable Grain Production

Summary

Intermediate wheatgrass (IWG) has potential to be the first widely grown perennial grain crop providing food for humans.

Long term outcomes of IWG grown in diverse cropping systems would include soil conservation, reduced nutrient leakage from fields, reduced pesticide application, and reduced farmer input costs.

We have begun to build a community of practice that will learn about IWG through three on-farm trials, breeding efforts, milling and baking experiments, and grain chemistry analysis. IWG has been planted on three farms, and we have learned about establishment challenges. We continue to make progress in breeding for increased seed size and yield.

Objectives/Performance Targets

• Increased optimism within the community of practice for potential of IWG to be a successful perennial grain crop. The community of practice is currently very interested in the potential of IWG to improve sustainability. Hands-on experience and documented progress in breeding will help us to move from interest to optimism.

• Knowledge and experience gained by farmers and processors enables them to provide direction to continued efforts to develop IWG. Breeders are currently operating according their best guesses. Once farmers and processors have obtained hands-on experience, they will be equipped to provide valuable insight concerning agronomic and breeding objectives.

• The number of farmers, processors and scientists interested in joining the IWG community of practice will have tripled in three years. Field days, publications, and tours will develop awareness of IWG, and a record of interested individuals will be maintained in preparation for expanded experimentation and planting.

• Commercial plantings of IWG will be established and breeding programs will be initiated in other regions. This is an intermediate term outcome. Commercial plantings depend upon the development of improved varieties, agronomic practices, processing techniques, and marketable products. Although the current project is based in Kansas, the research conducted will provide a head start to programs in other states throughout the North Central Region.

Accomplishments/Milestones

• Our plan was to have established intermediate wheatgrass (IWG) on three working farms in Kansas, and obtain first-year harvest data. In the fall of 2006, IWG was planted on three farms. Unfortunately, harsh conditions limited establishment success on two of the farms. One plot flooded out in the spring, and another did not germinate in the fall because there was no rainfall after planting. The third location established well and was harvested in 2007. On the farm with total establishment failure, replanting was done in fall 2007, and establishment appeared to be successful. We are waiting to see if the stand can recover from flooding at one location.

• Initial soil samples were collected in 2007 from each study location where at least partial establishment was achieved.

• We performed another cycle of bulked mass selection for seed size and threshability.

• We established a 4000-plant nursery to use in mass selection for seed size and yield.

• We intermated a small population of reduced-height (dwarf) IWG plants and established a nursery of progeny.

• We evaluated selection methods based on seed yield per head in spaced plants by using row plots derived from separate mother plants (in other words, half-sibling progeny testing). We are still in the process of analyzing the data from this experiment. Preliminary results indicate that selection for seed size in spaced plants or rows in the first year will successfully increase seed size in two-year-old plants growing in rows.

Impacts and Contributions/Outcomes

After only the first year of this project, progress toward the broad outcome of increasing optimism and experience with IWG has just begun. Successful establishment was only achieved on one farm, and we have not yet begun the milling/baking/seed testing phase of the project. However, we are gaining important pieces of unanticipated knowledge about IWG. For instance, our recommendation to farmers had been to plant IWG late in the fall as a means to avoid weed problems without chemical use. Now we have seen the risk that can come with late planting in Kansas—no rainfall until after the soil is frozen, which prevents establishment. In the second year, planting was earlier and very successful. Gaining key pieces of information, such as optimal planting time, will be critical for the community of practice to achieve increased confidence in growing IWG.

In the intermediate to long term, increasing IWG yield and seed size through plant breeding will be critical to achieving commercial success. Most plant breeding methodologies have been developed for domestic annual grain crops. We are continuing to develop and refine strategies for breeding perennial grain crops that are still rather wild. As we demonstrate the capacity to achieve rapid gains in yield and seed size, we expect support for intermediate wheatgrass to grow. Only when IWG is seen as an economically viable crop will it be widely planted and begin to provide sustainability benefits: reduced erosion, reduced nitrogen loss, reduced pesticide application, and increased net profit to farmers.

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