101-19 Use of Molecular Markers for Identity Preservation In St. Augustinegrass: Elucidating the Authenticity of ‘Raleigh' Samples From Sod Farms Across the Southeastern United States.



Monday, October 17, 2011: 4:15 PM
Henry Gonzalez Convention Center, Room 008A, River Level

Jennifer Kimball1, Carolina Zuleta1, Matthew Martin1, Kevin Kenworthy2, Ambika Chandra3 and Susana Milla-Lewis1, (1)North Carolina State University, Raleigh, NC
(2)Dep. of Agronomy, Univ. of Florida, Gainesville, FL
(3)Texas Agricultural Experiment Station, Texas A&M System, Dallas, TX
St. Augustinegrass (Stenotaphrum secundatum (Walt.) O. Kuntze) is a popular turfgrass in the southeastern United States due its superior shade tolerance and relatively low input requirements. However, among warm-season grasses, it is the most susceptible to severe freezing injury. In the early 1980’s, North Carolina State University released cultivar ‘Raleigh’ for its superior cold tolerance. Given that more than 25 years after its release, Raleigh is still the industry’s standard for cold tolerance, it is important to investigate whether or not St. Augustinegrass produced and sold as Raleigh across the Southeastern U.S. is true to putative ‘Raleigh’ selected in the late 1980s. The objective of this study was to use AFLP markers to assess genetic variability among five samples of original Raleigh and 46 samples of Raleigh obtained from sod farms in six different states. Foundation class and commercial samples of ‘Palmetto’ were included in the study as reference standards to gauge genetic diversity. To differentiate between Raleigh samples, fifteen AFLP primer combinations generated one hundred and twenty-three polymorphic loci, sixty-four percent of which could be attributed exclusively to seven samples. AFLP based genetic similarities among Raleigh samples in comparison with putative Raleigh ranged from 0.95 to 0.99. Phenetic analyses based on both unweighted pair-group cluster analysis and principal coordinate analysis revealed separation between putative Raleigh and the majority of the commercial samples into four different clusters. AMOVA results indicated that 87.78% and 12.22% of the total AFLP variation could be explained by differences among and within UPGMA clusters, respectively. Molecular markers analysis of vegetatively propagated cultivars is a useful tool to aid in identity preservation and identification of off-types.
See more from this Division: C05 Turfgrass Science
See more from this Session: Student Oral Competition: Stress Physiology, Breeding, & Genetics of Turfgrass