Poster: Late and Moved Abstracts

Abs # 933: Agrobacterium-Mediated Transformation of `Matador' Tall Fescue (Festuca arundinacea Schreb.) using a Mutant bas1 Construct for the Production of Dwarf Plants

Presenter:	Ayrapetov, Marina , mayr1229@postoffice.uri.edu
Authors	Ayrapetov, Marina  (A)   Longo, Chip  (A)   Thayer, Townsend  (A)   Pelloni, Aleatha  (A)   Jadosz, Amber  (A)   Birri, Jason  (A)   Scandariato, Justin  (A)   Gutgsell, Jessica  (A)   Lor, Zoa  (A)   Lor, Kia  (A)   Smith, Cameron  (A)   Luo, Hong  (A)   Neff, Michael  (B)   Chandlee, Joel  (A)   Kausch, Albert  (A)
Affiliations:	(A): University of Rhode Island (B): Washington University

Over 40 million acres of land in the United States is devoted to the growth of turfgrasses, of which 75% is utilized for lawns and along roadways creating tremendous environmental impacts. New genes can be introduced into grasses that confer valuable traits such as drought and stress tolerance, or insect and pest resistance. `Matador' tall fescue (Festuca arundinacea Schreb.) is a warm season, outcrossing, wind-pollinated, perennial turf used widely throughout the world. We have introduced a mutant bas1 gene fused to a ubiquitin rice promoter into `Matador' (tall fescue) to test induction of dwarfism. This approach has been demonstrated in Arabidopsis and tobacco to produce dwarf plants by altering the level of brassinosteroids available for plant growth. A unique class of plant hormones, brassinosteroids play a critical role in growth signaling throughout the life of the plant. ‘Matador’ embryogenic callus was co-infected with two strains of A. tumefaciens respectively containing the mutant bas1 vector and a tandem male sterility gene linked to the herbicide resistance selectable marker, bar. Putative transformants were analyzed by PCR to establish co-transformation frequencies. Position effect on the bas1 gene is expected to give rise to a range of phenotypes that will be screened in this study and analyzed for their effects on plant development. We expect to competitively inhibit brassinosteroid function within the plant, thus shortening internodes and slowing growth. The outcome of this project could result in a new slower growing tall fescue variety which could be used in private landscapes or urban municipality landscapes, while mitigating transgene escape and environmental safety.