HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Figures Only Full Text Free Full Text (PDF) Free Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in ISI Web of Science Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (4) Citing Articles via Google Scholar Google Scholar Articles by Lamb, J. F. S. Articles by Samac, D. A. Search for Related Content PubMed Articles by Lamb, J. F. S. Articles by Samac, D. A. Agricola Articles by Lamb, J. F. S. Articles by Samac, D. A. Related Collections Biofuels Crop Genetics Forage Management Alfalfa Plant and Environment Interactions

ALFALFA

Population Density and Harvest Maturity Effects on Leaf and Stem Yield in Alfalfa

^a USDA-ARS Plant Science Res. Unit and Dep. of Agronomy and Plant Genetics, Univ. of Minnesota, 411 Borlaug Hall, 1991 Upper Buford Circle, St. Paul, MN 55108
^b Dep. of Agronomy and Plant Genetics, Univ. of Minnesota, 411 Borlaug Hall, 1991 Upper Buford Circle, St. Paul, MN 55108
^c USDA-ARS Plant Science Research Unit and Dep. of Pathology, Univ. of Minnesota, 495 Borlaug Hall, 1991 Buford Circle, St. Paul, MN 55108

^* Corresponding author (lambx002{at}umn.edu)

Received for publication February 22, 2002. A system has been proposed using alfalfa (Medicago sativa L.) as a biofuel feedstock, where the stems would be processed to produce energy and the leaves used as a livestock feed. Our objectives were to evaluate the effects and interactions of environment, population density, and harvest maturity on leaf and stem yield of alfalfa germplasms differing in fall dormancy and leaf/stem ratio. Four alfalfa germplasms established at four population densities (450, 180, 50, and 16 plants m^-2) were harvested at the early bud and green pod maturity stages and evaluated in three environments for leaf and stem yield. All main effects and several two-way interactions influenced leaf and stem yield (P > 0.01). The population density x harvest maturity interaction had the greatest impact on yield. Leaf and stem yield per unit area increased as population density increased from 16 to 450 plants m^-2 at the early bud stage. In contrast, leaf and stem yield increased as population density increased from 16 to 180 plants m^-2, but decreased dramatically at 450 plants m^-2 at the green pod maturity stage. Delaying harvest until the green pod maturity stage and decreasing population density to 180 plant m^-2 maximized both leaf and stem yield in all four alfalfa germplasms studied. Decreasing population density to 180 plants m^-2, and harvesting twice per season at a later maturity stage would be a effective management strategy for maximizing yield in an alfalfa biomass energy or biofuel production system.

This article has been cited by other articles:

				J. F. S. Lamb, H.-J. G. Jung, C. C. Sheaffer, and D. A. Samac Alfalfa Leaf Protein and Stem Cell Wall Polysaccharide Yields under Hay and Biomass Management Systems Crop Sci., July 30, 2007; 47(4): 1407 - 1415. [Abstract] [Full Text] [PDF]