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Title: Ensuring coexistence of GE and non-GE alfalfa: status of current research efforts

Author
item Greene, Stephanie
item KESOJU, SANDYA - Washington State University
item Martin, Ruth
item EVANS, MARK - Washington State University
item Boydston, Rick
item WALSH, DOUG - Washington State University

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 5/5/2014
Publication Date: 7/9/2014
Citation: Greene, S.L., Kesoju, S., Martin, R.C., Evans, M., Boydston, R.A., Walsh, D. 2014. Ensuring coexistence of GE and non-GE alfalfa: status of current research efforts. Meeting Abstract. North American Alfalfa Improvement Conference, July 9 - 10, 2014, Lethbridge, Canada.

Interpretive Summary: Alfalfa is among the top five crops in the nation in terms of both farmgate value and total acreage. In 2011 a genetically modified form, resistant to the popular herbicide, glyphosate, was released, called Roundup®-Ready alfalfa (RRA). Since then grower demand for RRA seed has surged. However, many growers produce seed and hay for the export or organic market, which has very low tolerance for genetically engineered (GE) crops. Because coexistence of GE and non-GE crops is a top priority for the USDA, several research projects are exploring how we can ensure farmers can produce either GE or non GE crops without worrying about inadvertent contamination occurring from errant pollinators. This paper provides an over view and update on a current research project. In the fall (2012) and spring (2013), alfalfa fields were surveyed in alfalfa seed production areas in Washington, Idaho and California. RRA sources were identified as well as 43 “sink” fields (conventional alfalfa seed fields) located various distances from RRA sources. During the summer of 2013, pollinator surveys were conducted and seed harvested from the sink fields. This past winter we developed seedling assays to measure the amount of RRA found along the edges of our sink fields. Our first results confirm that as distance from RRA source fields increased, the level of RRA found in conventional seed fields decreased, but it varies depending on the direction. As we continue our research we will have a better handle on how climate, elevation, and other pollinators impact the movement of the RRA trait and can provide growers with information to ensure they can produce GE and non GE alfalfa.

Technical Abstract: Alfalfa routinely places among the top five crops in the nation in terms of both farmgate value and total acreage. In 2011 USDA APHIS announced the complete deregulation of glyphosate-resistant alfalfa in 2011. Since then grower demand for RRA seed has surged. Recognizing the need to support all facets of the market, industry has developed coexistence strategies. Because coexistence of GE and non-GE crops is a top priority for the USDA, several research projects have been funded to build on industry standards. This paper will provide an over view and update on a NIFA Biotechnology Risk Assessment Grant currently being conducted. In the fall (2012) and spring (2013), alfalfa seed and hay fields were surveyed in alfalfa seed production areas in Walla Walla Co., Canyon Co. and Fresno Co. and maps prepared showing the presence of RRA hay and seed fields and feral plant populations. Based on the maps, RRA sources (from seed fields and feral populations) and 43 sink fields (conventional alfalfa seed fields) located various distances from RRA sources were identified. During the summer of 2013, pollinator surveys were conducted and seed harvested every 30 m along the edges of sink fields. Parent seed lot and overall bulked samples of the 2013 harvest were also obtained for sink fields. This past winter (2014) we developed high throughput seedling assays to quantify level of RRA. We have begun testing seed lots from our sink fields. Our first results confirm that as distance between source and sink fields increase, the adventitious presence of RRA decreases. However, a significant directional impact was observed. Further research will help us understand whether this effect was due to wind, domicile position or other environmental factors.