Advanced Breeding, Development, and Release of High Biomass-energy Cane Cultivars in Florida

Research into alternative energy sources has been on the rise since the 1970s. Novel sources of carbon-neutral energy are currently in high demand, but can pose different challenges in their development. Energy cane is a relatively new generation crop being bred as a source for biofuel feedstock and ethanol production. Though originating from the sugarcane (Saccharum spp.) family, energy cane breeding strategies have diverged from the tradition goal of increasing sugars to maintaining a focus on selecting high biomass hybrids. These hybrids are derived from wide crosses between commercial sugarcane cultivars and S. spontaneum, a species within the Saccharum genus, which is characterized by high stalk counts and fiber content, excellent ratooning ability, and tolerances to abiotic and biotic pressures. A cooperative energy cane cultivar development program was established in 2007 between the USDA-ARS Sugarcane Field Station (Canal Point, Florida), and the University of Florida-EREC (Belle Glade, Florida) to produce high-yielding, and disease-resistant energy cane clones. After completing four years of multi-location field trials, disease screening, and fiber component analyses, the first-ever five energy cane cultivars developed in Florida were released in October 2014 (i.e., UFCP74-1010, UFCP78-1013, UFCP-82-1655, UFCP84-1047, and UFCP87-0053). Yields of the new cultivars are comparable to, or exceed the commercial check, L79-1002 (released in 2008). Disease data, derived from both field trials and artificial inoculation, indicate very low smut susceptibility when compared to the check; with no significant differences between the new releases. Fiber composition was comparable between the five energy cane clones and L79-1002. UFCP74-1010, UFCP78-1013, UFCP-82-1655, UFCP84-1047, and UFCP87-0053 have been released publically, and are intended for cultivation on the mineral soils within Florida. Improved strategic matings incorporating a wide range of germplasm, rigid disease screening protocols, and well-designed field trials have let to rapid improvement in clone cultivar development; with several cultivars currently in Stage II far exceeding the yields and disease ratings of both L79-1002 and some of the 2014 releases. Florida provides the most desirable location in the Unites States to breed sugarcane, and thereby energy cane as a specialized derivative product. Current cultivar development foci include: increasing genetic diversity by optimizing matings with related genera; incorporation of abiotic stress tolerances; continuing the trend in yield increases and disease tolerances; and evaluating cultivars in diverse environments across the county to help target alternate locations where energy cane is desired and can be grown as a biofuel feedstock.