ARS | Publication request: North American Legumes for Rangeland Restoration, Conservation, and Forage Production in the Western U.S.

Submitted to: Society for Range Management Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: September 30, 2006
Publication Date: February 9, 2007
Citation: Johnson, D.A., Bhattarai, K., Jones, T.A., Bushman, B.S., Gardner, D.R. 2007. North American Legumes for Rangeland Restoration, Conservation, and Forage Production in the Western U.S.. Society for Range Management Meeting Abstracts.

Technical Abstract: Land managers do not have many alternatives to choose from when seeding North American legume species on rangelands of the western U.S. As part of an initiative to address that need, research was conducted with basalt milkvetch (Astragalus filipes), western prairie clover (Dalea ornata), and Searls prairie clover (Dalea searlsiae) to evaluate the potential of these three North American legume species for use in restoration, conservation, and forage production applications. Seeds were collected, and associated site data were obtained from a diversity of sites where these species occur in the western U.S. and British Columbia. This included 77 sites for basalt milkvetch, and 25 sites each for western prairie clover and Searls prairie clover. Annual precipitation at the collection sites ranged from 127 mm in southwestern Nevada to more than 500 mm in northeastern California, and elevations ranged from 200 to 2,500 m. Forage analysis showed that nitrotoxins (3-nitropropanol), selenium, and swainsonine were non-detectable or extremely low for all collections. Research is underway to isolate and identify rhizobial strains that are infective and effective at nitrogen fixation for each of the three legume species. Plants from each of the collections of the three legume species were established at two field sites in northern Utah and are being evaluated for their morphological characteristics, plant vigor, forage yield and quality, seed production, and regrowth. Informative AFLP DNA primer pairs were used to genetically characterize the collections of basalt milkvetch. Estimates of genetic diversity were obtained with 1,200 AFLP markers, and a phylogenetic tree was constructed for the collections. These molecular data will allow identification of optimal germplasm releases to most effectively represent existing genetic variation in basalt milkvetch across its range of distribution.