|SHEAFFER, C - UNIV OF MINNESOTA
|CUOMO, G - UNIV OF MINNESOTA
Submitted to: American Forage and Grassland Council Conference Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 7/14/2002
Publication Date: 7/16/2002
Citation: LAMB, J.F., SHEAFFER, C.C., CUOMO, G.J. DEVELOPING ALFALFA FOR USE AS A BIOMASS ENERGY OR BIOFUEL FEEDSTOCK. AMERICAN FORAGE AND GRASSLAND COUNCIL PROCEEDINGS. 2002. ABSTRACT. P. 69.
Technical Abstract: A system has been proposed using alfalfa (Medicago sativa L) as a biofuel feedstock, where the stems would be processed to produce energy or fuel and the leaves used as a livestock feed. Our objectives were to evaluate the effects and interactions of environment, plant density, and harvest maturity on leaf and stem yield of alfalfa germplasms differing in genetic origin, fall dormancy, size of stem, and leaf to stem ratio. Alfalfa germplasms established at four population densities (42, 16, 5, and 1.5 plants/ft2) were harvested at early bud and green pod maturity stages and evaluated for leaf, stem, and total yield and leaf and stem crude protein (CP) and neutral detergent fiber (NDF) concentrations. The population density x harvest maturity interaction had the greatest impact on all yield components. Forage, leaf, and stem yield per unit area tended to increase as plant density increased from 1.5 to 42 plants/ft2 at the early bud stage. In contrast, at the green pod maturity stage forage, leaf and stem yield increased as plant density increased from 1.5 to 16 plants/ft2, but at 42 plants/ft2 forage yield dropped off dramatically. Leaf and stem CP concentration was greater at early bud, while leaf and stem NDF concentration was greater at green pod. Population density had a minimal effect on forage quality traits. Large stemmed Flemish alfalfa germplasms had less stem CP and greater stem NDF concentrations compared to alfalfa cultivars adapted to the Upper Midwest. The greatest leaf, stem, and forage yield occurred at the green pod maturity stage at the 16 plants/ft2 treatment. Delaying harvest until the green pod maturity stage and lowering plant population density to 16 plants/ft2 maximized both leaf and stem yield for all alfalfa germplasms.