Lignocellulosic feedstocks: research progress and challenges in optimizing biomass quality and yield

Lignocellulosic biomass derived from energy crops and agri-cultural residues is a promising renewable source for the pro-duction of transportation fuels and bio-based materials. Plants exhibiting C4 photosynthesis are amongst the most promising dedicated energy crops as they possess tremendous intrinsic effi-ciency in converting solar energy to biomass. Van der Weijde et al. (2013) provide an excellent overview of the potential of five C4 grasses from the Panicoideae clade (maize, Miscanthus, sorghum, sugarcane, and switchgrass) as lignocellulosic feedstock for the production of biofuels. The authors discuss yield poten-tial, biomass quality and genetic improvement of dual-purpose food and energy cultivars and dedicated energy cultivars through plant breeding and also highlight several research needs. Perennial growth habit provides a number of environmental advantages over annuals as bioenergy crops, including the requirement o