Submitted to: Crop Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: January 12, 2013
Publication Date: April 18, 2013
Repository URL: http://handle.nal.usda.gov/10113/56241
Citation: Vogel, K.P. 2013. Comparison of two perennial grass breeding systems with switchgrass. Crop Science. 53:863-870. DOI: 10.2135/cropsci2012.09.0559 Interpretive Summary: Two breeding systems for improving switchgrass for use as a forage or biomass energy crop were evaluated for their effectiveness in developing improved cultivars. One breeding method known as the Multi-step Family Selection system theoretically had the potential to result in greater breeding gains per generation but required more work and to date had not been field evaluated. The other method that was tested is known as the Between-and-within family selection system. It requires less field and breeding nursery maintenance work in comparison to the Multi-step Family breeding method. The Between-and-within family selection system produced experimental strains that had the greatest biomass yields and it has the most potential for developing improved switchgrass cultivars for use in pastures and biomass energy production fields.
Technical Abstract: Two breeding systems for sexual perennial grasses were compared using three switchgrass populations to determine which method was the most effective in improving biomass yield and in vitro dry matter digestibility (IVDMD). The two methods that were compared were the Between- and- within- family- selection (BWFS) and Multistep- family-selection (MSF) breeding systems. With the BWFS, half-sib families are produced and evaluated on a family basis for two or more years and then the best plants within the best families are selected for polycrossing to produce the first synthesis (Syn 1) generation which is then tested for potential release as a new cultivar. With the MFS, the parent genotypes of the half-sib families being evaluated in the BWFS selection nursery are maintained and the genotypes whose progeny were the best in the BWFS evaluation trial are selected and polycrossed to produce a new strain for testing. The methods were compared using two switchgrass populations in which improved biomass yield and IVDMD were the selected traits and with another population in which improved IVDMD and winter survival were the selected traits. For two populations, the BWFS breeding system produced strains with significantly greater biomass yields than the MFS system. For IVDMD, the MSF system resulted in greater IVDMD for one breeding populations but for the other two populations there was either no differences or the BWFS system produced a strain with greater IVDMD. Overall, there were no advantages to using the MFS system in comparison to the BWFS breeding system and BWFS required less work.