Project Number: 5428-21000-014-11
Project Type: Specific Cooperative Agreement

Start Date: Jul 16, 2009
End Date: Jul 15, 2014

Objective:
The objectives of this cooperative research project are: 1) Evaluate the relative livestock performance when grazing mixtures of pasture grasses and legumes; and 2) Evaluate the productivity of grass and legume mixtures; and 3) Breed pasture grasses and legumes with enhanced compatibility for use in grazing.

Approach:
This research is an expansion and continuation of the research goals and objectives originally started under SCA #58-5428-4-373 entitled "Develop and evaluate plants for improved livestock performance." The new research will determine livestock performance and pasture productivity of grass-legume mixtures in comparison to commercially fertilized grass monocultures. Standard check cultivars and germplasm from ongoing ARS breeding programs will be established in large and small scale research plots. Large scale plots will be used to compare/determine animal performance, carrying capacity, and nutritional content of grass monocultures versus grass and legume mixtures. Results will be based upon livestock weight gain, forage dry matter production, and in-vitro forage quality analyses. Small plots, using multiple species of grasses and legumes in varying composition ratios, will be established to determine optimum grass-legume mixtures and plant densities that maximize pasture productivity in comparison to commercial fertilizer. Livestock grazing on these plots will ensure realistic pressures common to pastures. The role that endophyte infection of grasses has on grass-legume mixture compatibility may be evaluated. Livestock and plant data will be utilized in plant improvement programs to breed for improved compatibility among pasture grasses and legumes.