|Anderson, William - Bill|
Submitted to: American Forage and Grassland Council Conference Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 5/14/2004
Publication Date: 6/14/2004
Citation: Anderson, W.F., Burton, G.W., Hanna, W.W., Davis, M. 2004. Coastcross II bermudagrass. Proceedings of Conference of American Forage and Grassland Council. 13:526.
Interpretive Summary: not required
Technical Abstract: Coastcross II (CC II) originated from mutating Coastcross I (CCI) with gamma radiation in 1971 and selecting for improved cold tolerance. Coastcross I was released in 1972 because of quick establishment, improved dry matter yields and much higher digestibility than Coastal. However, CCI failed to produce rhizomes and lacked winterhardiness. Burton et al reported efforts to irradiate approximately one-half million green stems of CCI with gamma rays and plant them in northern Georgia to screen for winterhardiness. Only four plants survived which were similar in all characteristics to CCI. Data from a three year yield trial (1974 to 1976) in Tifton, GA the reported similar yields between CC I, the mutant and Coastal. After a moderately severe winter the yield data from the summer of 1977 indicated that the winter-hardiness in one of the mutant lines (CC II) was better than CC I, though not as hardy as Coastal. This mutant was tested over four years (1980-1983) giving yields comparable to Coastal (12,093 lbDMac-1 vs. 11,916 lbDMac-1), and consistently higher digestibilites (5-8% IVDMD) in Tifton, GA. In a clipping trial at the Gulf Coast Research and Extension Center in Fairhope, Alabama, CC II had higher dry matter yields (10,877 lbDMac-1 and 9,585 lbDMac-1) than Coastal (10,256 lbDMac-1 and 9385 lbDMac-1) and was comparable to Tifton 85 (10,338 lbDMac-1 and 9,860 lbDMac-1) in 2002 and 2003, respectively. Yields of CC II (15,048 lbDMac-1) were higher than Coastal (9,314 lbDMac-1) and CC I (13,244 lbDMac-1) from the first year of a clipping trial established in Tifton, Georgia. Establishment ratings of CC II plots in this trial were significantly better than CC I. In vitro digestibility (IVDMD) of forage in this trial supports earlier data that CC I and CC II had better digestibility than Coastal. Measured plant characteristics were similar between CC I and CC II with both being more coarse than Coastal but less coarse than Tifton 85. Chemical (HPLC analysis for flavonoids) and genotypic (AFLP analysis) data verified the genetic similarity between CC I and CC II. Field trials have been established in North Alabama to determine winter-hardiness and yields. Survivability ratings will be presented. Results suggest that Coastcross II is a viable alternative bermudagrass cultivar for the Southeast.