DNA AMPLIFICATION FINGERPRINTING ANALYSIS OF BERMUDAGRASS (CYNODON) -GENETIC-RELATIONSHIPS BETWEEN SPECIES AND INTERSPECIFIC CROSSES

We have used DNA amplification fingerprinting (DAF) to study the genet ic variation of bermudagrass (Cynodon) species and cultivars of inters pecific crosses that exhibit leaf-blade textural characteristics rangi ng from coarse to fine. Arbitrary octamer primers produced complex and reproducible amplification profiles with high levels of polymorphic D NA. Phylogenetic analysis using parsimony (PAUP) and unweighted pair g roup cluster analysis using arithmetic means (UPGMA) grouped 13 bermud agrass cultivars into several clusters, including one containing the A frican-type bermudagrasses (C. transvaalensis) and another containing the common-type bermudagrasses (C. dactylon). The latter group include d C. magennissii ('Sunturf') and a interspecific C. transvaalensis x C . dactylon cross ('Midiron'), 2 cultivars that exhibited leaf textural characteristics closer to the common-types. All other C. transvaalens is x C. dactylon crosses grouped between the African and common types. An extended screen of 81 octamer primers was needed to separate culti var 'Tifway' from the irradiation-induced mutant 'Tifway II'. The use of either template endonuclease digestion prior to amplification or ar bitrary mini-hairpin primers increased detection of polymorphic DNA an d simplified the task of distinguishing these closely related cultivar s. Alternatively, the use of capillary electrophoresis (CE) resolved f ingerprints adequately and detected products with high sensitivity, th ereby promising to increase throughput and the detection of polymorphi c DNA. When used to fingerprint samples from commercial sources, DAF i dentified bermudagrass plant material on the basis of unique reference profiles generated with selected primers. DAF represents an excellent technique for bermudagrass cultivar verification, seed certification, varietal protection, and for the identification of mistakes in planti ngs, mislabeled plant materials, and contamination or substitutions of sod fields.