Improving switchgrass for the biomass industry
Claessens, A. and Langevin, F. 2022. Improving switchgrass for the biomass industry. Joint Canadian Weed Science Society/Canadian Society of Agronomy meeting, Halifax, NS, November 14-17, 2022. Oral presentation.
Switchgrass (Panicum virgatum L.) has been identified as a sustainable cellulosic biofuel feedstock due to its perennial life cycle, broad adaptability, low reliance on synthetic inputs and water, as well as its fiber quality (Frank et al., 2004). Additionally, switchgrass cultivation can provide ecosystem services benefits such as reduced soil erosion and fertilizer runoff, increased soil carbon sequestration and wildlife habitat (Wang et al., 2020). Switchgrass has an enormous reservoir of genetic diversity that remains to be fully exploited for varieties improvement. In our breeding program, we are targeting traits such as yield, fiber content, and crop establishment through indirect selection for plant winter survival, plant height, stem width, and seed weight and against lodging and stem density. Two breeding methods were used: recurrent selection (among families or among-and-within-families) within one genetic background (cv. Cave-in-Rock) and the development of lowland x upland hybrids. Our results from a field evaluation trial establish in Québec in 2021, demonstrated that improvement can be achieved for higher plant height, lower stem density, and higher seed weight through recurrent selection, which resulted in an increase of up to 1 Mg/ha of biomass yield in the first production year. However, more field data are needed to determine the optimal potential of these new populations. Our results also demonstrated that more cycle of selection will be needed within high winter hardiness lowland x upland hybrids to significantly improve their biomass yields compared to the cultivar Cave-in-Rock.