Genetic Variation and Estimation of Ethanol Yield of Alamo Half-Sib Families.

Biofuels such as ethanol and biodiesel are considered as alternative sources of energy that have gained popularity over the years and switchgrass is considered one of the most promising crop for biomass yield improvement for use as a biofuel feedstock. In this study, half-sib families were derived from a four-year-old population sward of Alamo cultivar in 2007 at the Holston unit of East Tennessee Research and Education Center (ETREC). Out of the 230 selected plants in 2011, 62 half-sib families were retained for a replicated field trial in 2012 at two Tennessee locations, Holston unit-ETREC in Knoxville and Plateau Research and Education Center (PREC) in Crossville.  Half-sib plants were established in a spaced-planted nursery, using a randomized complete block design with 3 replications. Each family was planted in a single-row-plot of 9 plants 30cm apart, and 90cm between rows. Random tillers were collected from each individual plant in 2013 while hand-grab samples were collected in 2014. Samples were dried in a batch oven for 24-48 hours at 48.9^oC. Dried samples were finely ground and analyzed using a SpectraStar XL Near-infrared Spectrometer (NIRS) to determine ethanol yield. Ethanol yield will be estimated using the procedure by Lorenz et al. (2009) and analyzed through analysis of variance (ANOVA) using MIXED model methods in SAS (SAS v9.4, Cary, NC). Variance estimates will be obtained using the Restricted Maximum Likelihood of the MIXED model methods in SAS (SAS v9.4, Cary, NC).