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ARS Home » Plains Area » Fort Collins, Colorado » Center for Agricultural Resources Research » Agricultural Genetic Resources Preservation Research » Research » Publications at this Location » Publication #364992

Research Project: Efficient and Effective Preservation and Management of Plant and Microbial Genetic Resource Collections

Location: Agricultural Genetic Resources Preservation Research

Title: Maintaining genetic purity in alfalfa seed fields

item KESOJU, SANDYA - Columbia Basin College
item Greene, Stephanie

Submitted to: Hay and Forage Grower
Publication Type: Popular Publication
Publication Acceptance Date: 1/25/2019
Publication Date: 3/1/2019
Citation: Kesoju, S., Greene, S.L. 2019. Maintaining genetic purity in alfalfa seed fields. Hay and Forage Grower. 34(2):8-10.

Interpretive Summary: n/a

Technical Abstract: Alfalfa is an important livestock feed, especially for dairy production and horses. Genetically-modified (GMO) resistance to glyphosate herbicide became available to farmers in 2011. In 2014, a second GMO trait, reduced-lignin, was deregulated and marketed as HarvXtra. Traditional alfalfa varieties need to be cut prior to significant flowering if high-quality hay is desired. The reduced-lignin HarvXtra alfalfa trait helps solve the nutritional quality issues associated with delayed cutting, providing hay growers with greater flexibility in harvest timing and potentially boost forage yields. However, more plants will reach the flowering stage and perhaps lead to a higher risk for adventitious presence (AP, or unwanted genes in seed lots) of GMO genes in areas where non-GMO varieties are grown for seed. Although industry has established coexistence standards that help mitigate AP, further research is needed. This paper discusses a study where AP was examined, where the GE source was from GE hay fields. We did detect gene flow from hay to seed fields, but it was at a very low level. The range in distances suggested that AP was also influenced by field-to-field variation, such as pollinator behavior, pollen availability, and field size. Though the distances in our study were well below the current AOSCA Alfalfa Seed Stewardship Program isolation distance of 2 miles that is required to separate AP-sensitive seed production from GMO alfalfa hay production, with the release of HarvXtra alfalfa the risk of gene contamination becomes greater where producers choose to significantly delay harvest dates. Successful coexistence depends on the widespread implementation of practices that minimize the gene flow by either seed or pollen. These practices will help ensure alfalfa producers can continue to target GMO and non-GMO markets.