Preliminary Assessment of Hybrid Poplar Biomass Qualit

The increase in biomass yield from genetic improvement is important; however, awareness of biomass quality as it impacts processing performance is increasing.  Surprisingly little information on chemical composition of poplar is available in the open literature, despite its development as a chemical feedstock.  Responding to this information gap, 13 poplar trees were harvested from trials in northern Minnesota and shipped to Tennessee for processing and analysis.  Standard chemical analysis methods were used to determine major constituents -- cellulose, hemicellulose, lignin, and extractives. The variation in composition was very limited, and no discernible link to different varieties could be made. To further probe variation, principal component analysis of data from FTIR and pyrolysis-gas chromatography/mass spectroscopy was conducted.  PCA of py-GC/MS data was consistent with wet chemistry results in that within-clone variation was as great as between-clone variation.  Interestingly, distinct clusters were observed for different varieties using FTIR spectral data.  This suggests that, although clonal differences in chemical makeup are minimal, other structural features of the cell wall are clearly impacted by genetics. This presentation will discuss the implications of this preliminary insight and highlight the need for continued research into genetic manipulation of biomass quality for energy crops.