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Submitted to: Southern Pasture and Forage Crop Improvement Conference Proceedings
Publication Type: Abstract Only Publication Acceptance Date: 3/31/2006 Publication Date: 4/13/2006 Citation: Anderson, W.F. 2006. Perennial grass breeding program for forage and biofuels - Tifton, Ga. Southern Pasture and Forage Crop Improvement Conference Proceedings. Interpretive Summary: not required Technical Abstract: Forage improvement of bermudagrass and bahiagrass continues within the Crop Genetics and Breeding Research Unit of USDA/ARS. Recently, a new effort has begun within the unit toward developing perennial grass crops as feedstocks for bio-energy in the Southeast. An emphasis beginning three years ago in the forage breeding program was to evaluate and reestablish the 600 plus forage bermudagrass (Cynodon spp.) plant introduction nursery. A reevaluation of the material was begun by assessing phenotypic traits such as plant height, leaf width and length, coarseness of stems as well as ploidy levels by use of a flow cytometer. The entire nursery was re-established first in pots in the greenhouse then by replanting at a new location in the spring of 2004. These plots underwent further evaluation for traits such establishment rate, stolon number and length. From the entire collection a core collection of 170 genotypes was developed using clustering analysis of fourteen phenotypic traits and ploidy levels. The core collection is currently being evaluated for in vitro digestibility, fall armyworm resistance, shade tolerance and chemical attributes. Amplified fragment length polymorphisms (AFLP) have indicated great amounts of genetic variability that may be used for development of molecular markers to assist breeding for important traits. Synthetic seeded breeding lines and a vegetatively propagated hybrid bermudagrass are being evaluated for release along with a fast germinating bahiagrass. Seeded forage bermudagrass with cold tolerance continue to be goals for forage improvement within the breeding program. Agronomic studies that involve fertilization rates and sod based rotations are also underway. A greater emphasis has been placed on evaluating perennial grasses as feedstocks for conversion to bio-energy or bio-fuels. It is necessary to evaluate germplasm for traits that make conversion more efficient, then breed or engineer plants with lower lignin or with cell-wall structures more amenable to decomposition. Digestion by rumen microbes correlates very well with desirable traits for conversion to ethanol. A multi-species test has been established to determine comparative biomass yields, nutrient cycling, and carbon sequestration. Napiergrass (Pennisetum purpurem), giant reed (Arundo donax), and bermudagrass are among the species under evaluation as potential dedicated crops for bio-energy in the Southeast. |
