ABSTRACT
Switchgrass (Panicum virgatum L.), a native warm-season perennial grass found throughout the US, characteristically produces high biomass yields annually with low inputs, and can grow on marginal land. Since the introduction of the Department of Energy’s Bioenergy Feedstock Development Program over 3 decades ago, switchgrass has been the subject of intensive study, yielding a plethora of data regarding plant growth and stress resistance. As a C4 species, switchgrass is effi cient at converting the sun’s energy into carbohydrate compounds, and combined with being
1The Institute for Sustainable and Renewable Resources, The Institute for Advanced Learning and Research, Danville, VA, USA; Departments of Horticulture and Forest Resources and Environmental Conservation, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA. Email: barry.fl inn@ialr.org 2The Institute for Sustainable and Renewable Resources, The Institute for Advanced Learning and Research, Danville, VA, USA. Email: alejandra.lara@ialr.org 3The Institute for Sustainable and Renewable Resources, The Institute for Advanced Learning and Research, Danville, VA, USA; Department of Horticulture, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA. Email: scott.lowman@ialr.org *Corresponding author: chuansheng.mei@ialr.org
perennial, the plant offers much promise for future biomass production on a large scale, helping offset the use of fossil fuels. In fact, switchgrass yielded 504% of the energy consumed in a large, multi-farm study in the Central Plains (Schmer et al. 2008), and stands can produce for more than a decade. Furthermore, compared with other bioenergy crops, switchgrass cultivation is relatively simple and requires no specialized equipment by the producer. While yields are high, much more could further be improved for bioenergy purposes. Benefi cial plant-microbe interactions, a fi eld of study generating much interest in the past two decades, offer new solutions to improve switchgrass biomass yields, stress tolerance, fi rst-year establishment, and sustainability.
