Phenotypic Traits Of Switchgrass Cultivars Associated With Increases In Biomass Yield.

One percent annual increases in switchgrass biomass yields are needed to meet the goals of the 2011 Billion Ton Vision update. This study aims to examine the anatomical, morphological, and physiological traits that are associated with biomass yields in forage-type and improved bioenergy-type cultivars of switchgrass across ploidy levels and ecotypes to find traits that have already been associated with increased biomass yield. Knowledge of which traits are associated with yield increases from direct selection for yield may decrease the time scale for future breeding efforts.  A randomized incomplete block design variety trial was established at the Energy Biosciences Institute Research Farm in the spring of 2012 in Urbana, IL. Beginning in the spring of 2013, leaf area index and height was measured on each cultivar throughout the growing season to estimate the development of each canopy along with relative chlorophyll concentrations and heading date to quantify the duration of photosynthetic activity. Additionally, we measured stomata size and density, and genome size on each cultivar. At harvest, fresh weight, dry weight, tiller mass, tiller density, internode number, and biomass yield will be measured. Statistical analysis will determine if differences in phenotypic data are correlated with biomass yield.