Genetic variances for dry matter yield, nitrogen content, and nitrogen yield in crested wheatgrass-alfalfa mixtures.

Asay, K.H.
Mayland, H.F.
Rangeland Ecology & Management / Journal of Range Management Archives
Publication Year: 
Since its introduction from Asia in the early 1900s, crested wheatgrass [Agropyron cristatum (L.)Gaertner, A. desertorum (Fisch. ex Link) Schultes et al.] has had a major impact on the improvement of western rangelands of North America. Most of the early seedings with this cool-season grass were made as monocultures. Present and projected use of rangelands, however, prescribe that future crested wheatgrass cultivars have the genetic potential to be an effective component in a species complex including other grasses, shrubs, and forbs. The present study was conducted to evaluate the effect of associated alfalfa (Medicago sativa L.) on the performance and genetic variability in a 50-clone sample of a tetraploid crested wheatgrass breeding population. Significant (P < 0.05) differences were found among the clonal lines for dry matter (DM) yield, nitrogen (N), and N yield. Opportunities for genetic improvement, as indicated by the magnitude of the genetic variation for these characters, was significantly increased when the grasses were grown in association with alfalfa. Significant (P < 0.01) and positive correlations of clonal means between stand types indicated that differences among the clonal lines in DM yield, N content, and N yield were relatively consistent when grown with or without alfalfa. These results indicate that initial screening could be effectively done in tetraploid crested wheatgrass in the presence or absence of alfalfa. Final evaluation of breeding lines and experimental strains, however, should be done with alfalfa if the object is to develop cultivars to be grown in combination with that species.
Document Type: 
Journal Issue/Article
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Rangeland Ecology & Management (formerly the Journal of Range Management) serves as a forum for the presentation and discussion of facts, ideas, and philosophies pertaining to the study, management, ecology, and use of rangelands and their resources. The journal is peer-reviewed and provides international exchange of scholarly research and information among persons interested in rangelands. The Global Rangelands collection includes REM content up to 5 years from the current year. More recent content is available by subscription from BioOne and the Society for Range Management, and may be available at your local university library.
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