Conservation of Crop Wild Relatives in the USA

  • Karen A. WilliamsEmail author
  • Stephanie L. Greene


Crop wild relatives (CWR) are found throughout the USA, with a high concentration in the eastern part of the country. These wild plants include the ancestors of crops domesticated within the borders of the country, such as sunflower, pecan, blueberry, cranberry, and squash, as well as the relatives of crops domesticated elsewhere. This chapter presents an overview of some of the CWR found in the USA and the status and potential for improved conservation through both ex situ and in situ approaches. The largest collection of CWR germplasm from the USA is the National Plant Germplasm System, managed by the US Department of Agriculture, Agricultural Research Service (USDA-ARS). Other germplasm conservation networks, including the Bureau of Land Management-led Seeds of Success, the Center for Plant Conservation’s Collection of Endangered Plants, and the American Public Gardens Association/US National Arboretum-coordinated Plant Collections Network, support collection and conservation of plants that include CWR. Active sampling of CWR for ex situ conservation is ongoing, especially for certain crop groups, such as potato, sunflower, and small fruits. In situ conservation of CWR is mostly passive, involving protected areas that were established for other objectives. Ample opportunities exist to fill gaps in ex situ collections and to more deliberately conserve CWR on public lands, particularly by making better use of available sources of information, harnessing existing frameworks, and developing new partnerships.


Crop wild relatives Wild utilized species Ex situ conservation In situ conservation National Plant Germplasm System United States 


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© This is a U.S. government work and not under copyright protection in the U.S.; foreign copyright protection may apply 2018

Authors and Affiliations

  1. 1.USDA, Agricultural Research Service, Beltsville Agricultural Research Center, National Germplasm Resources LaboratoryBeltsvilleUSA
  2. 2.USDA, Agricultural Research Service, Center for Agricultural Resources Research, National Laboratory for Genetic Resources PreservationFort CollinsUSA

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