1.14.14.96	biofuel production	lignocellulosic materials provide an attractive replacement for food-based crops used to produce ethanol. Understanding the interactions within the cell wall is vital to overcome the highly recalcitrant nature of biomass. One factor imparting plant cell wall recalcitrance is lignin, which can be manipulated by making changes in the lignin biosynthetic pathway. Eucalyptus trees with down-regulated cinnamate 4-hydroxylase (C4H) or p-coumaroyl quinate/shikimate 3'-hydroxylase (C3'H) expression display lowered overall lignin content. Lowering lignin content rather than altering sinapyl alcohol/coniferyl alcohol/4-coumaryl alcohol ratios is found to have the largest impact on reducing recalcitrance of the transgenic eucalyptus variants. The development of lower recalcitrance trees opens up the possibility of using alternative pretreatment strategies in biomass conversion processes that can reduce processing costs	742154