Random amplified polymorphic DNA analysis of water spinach (Ipomoea aquatica) in Florida

The genetic relationship between three biotypes of water spinach (Ipomoea a quatica Forsk.), including one 'upland' agricultural cultivar and two float ing wild biotypes collected from Hillsborough County, Florida, were evaluat ed using Random Amplified Polymorphic DNA (RAPD) markers, Forty-eight decam er primers were screened; eighteen of these were informative and yielded 18 8 resolvable bands, of which 58 (31%) were polymorphic. Five primers produc ed unique DNA fingerprints useful for identification of the biotypes and fi ngerprints of the biotypes from two primers are presented. Phenetic analysi s of the banding patterns grouped the three biotypes within unique clusters which bootstrap analysis further confirmed. Furthermore, while there is bo otstrap evidence that the 'Cultivated' type is distinct, there is no eviden ce that the cultivated variety has diverged from the wild types to any grea ter extent than the wild types are different from each other. Marker variat ion occurs mainly between the biotypes (78%) which may reflect the limited number of farmers, limited wild type introductions, and frequent clonal rep roduction, but also reflects the severely limited sample size.