Biomass characteristics in Mediterranean populations of Piptatherum miliaceum—A native perennial grass species for bioenergy

Abstract

Native Mediterranean perennial grasses may represent a suitable feedstock for bioenergy production, combining high yields with environmental and economic benefits. This research aimed at evaluating bioenergy traits in Mediterranean germplasm of the perennial species Piptatherum miliaceum (L.) Coss., smilo grass, grown under rainfed conditions in Sardinia (Italy). Ten autochthonous populations and a check species, tall fescue (Festuca arundinacea Schreb.) were investigated for maturity, biometric traits, biomass production and quality.Smilo grass populations differed for flowering date, biometric traits, yield and biomass quality traits. Aboveground dry matter ranged from 651 to 1136g plant−1, suggesting a huge potential peak yield (about 40tha−1). The highest productive populations out-yielded the check species. Cellulose content was approximately 40% in tillers and leaves. Heating value ranged from 16.3 to 18.2MJkg−1 in leaves and tillers, respectively. The ultimate analysis of biomass revealed relatively high contents of chlorine and sulfur. A significant correlation was found between dry matter yield and number of tillers per plant. The general outcome of our experiment evidenced interesting traits for bioenergy production in smilo grass with favorable combinations of biomass yield and lignocellulosic contents. Additional research is still required to investigate long-term performances of smilo grass crops and effect of management on biomass yield and chemical composition.