Submitted to: Genbank
Publication Type: Germplasm Release
Publication Acceptance Date: 7/16/2008
Publication Date: 7/16/2008
Citation: Kamps, T.L., Ortega, V.M., Williams, N.R., Chamusco, K.C., Scully, B.T, Chase, C.D. 2008. Batch submission and release of genomic survey sequences (GSS) derived from leaf tissue of bermudagrass (C. transvaalensis X C. dactylon)cultivar 'Tifway'. GenBank, National Center for Biotechnology Information. GenBank Accession Nos. Fl107130 to Fl107199 and Fl107237 to Fl107258. Interpretive Summary:
Technical Abstract: The nine species of the genus Cynodon are characterized as sod forming, perennial, warm-season grasses. The bermudagrasses have broad economic impact as both forage and turf crops in tropical to transitional regions. The tetraploid (2n=4x=36) common bermudagrasses generally spread aggressively, are tolerate of drought, heat, and high foot traffic, but are intolerant of shade and low temperatures. Morphologically, their leaves are highly variable, ranging in texture and color from medium to course, and light to dark green, respectively. Distinctive features of the diploid species (2n=2x=18), C. transvaalensis include fine leaf texture with color ranging from light green to yellow, an intolerance to low water conditions, very high shoot density, and spread less aggressively than typical C. dactylon accessions. The two species are cross compatible and improved turf-types adapted to specific uses have been developed from the resulting interspecific triploid hybrid progeny. Cultivars of similar growth habits but differing in their responses to environmental cues are generally difficult to distinguish based on morphological and physiological phenotypes. Consequently, taking advantage of the features afforded by co-dominant markers and PCR technology we generated a genomic library enriched for the (CA)n simple sequence repeat (SSR) motif using the widely planted hybrid bermudagrass cultivar “Tifway”. Random sampling and DNA sequencing of 88 clones found the library enrichment methodology for the (CA)n motif was successful in that 54 (ca. 61%) contain this motif with a minimum of five repeats. Seven of these clones, however, lacked sufficient flanking sequence for primer design. Other di-, tri-, tetra-, and pentanucleotide repeat motifs were identified in 11 of the remaining 34 sequenced clones. BLASTn analysis revealed six clones to have significant pair-wise sequence similarity. Consistent with SSR hypervariability expectations, the dissimilarity within each of the three pairs included the length of the repeat motif. BLASTn and tBLASTx against the TIGR Graminae Repeats.v2 database also identified significant sequence homology of one clone to a Tourist-like MITE transposon element. The SSR containing clones provide a valuable resource of co-dominant PCR based molecular markers for genetic linkage mapping and genotype fingerprinting of Cynodon sp. and their near relatives. As molecular probes and potential SNP markers the remaining GSS clones can also have similar applications.