AFLP fingerprinting in Pelargonium peltatum:: Its development and potential in cultivar identification

Pelargoniums are of considerable commercial importance, mainly because they are highly decorative and relatively easy to cultivate. As the numbers of pelargonium cultivars are continuously increasing, the adoption of reliable and discriminant molecular tools capable of identifying new cultivars and determining their diversity with respect to already registered ones promises to be the prime requirement for a valuable decorative plant market, as well as a genetic guarantee of the value of plant materials. A judicial trial offered a unique opportunity to develop an innovative line of research for molecularly characterizing Pelargonium peltatum genotypes on the basis of RAPD and AFLP fingerprinting. The DNA polymorphism of a pelarglonium flower recovered at the site of a crime was compared with those of nine plants seized in the house of the suspected murderer. Once an efficient protocol for isolating genomic DNA in pelargonium had been optimized, a total of 162 RAPD and 568 AFLP markers were detected using respectively twenty 10-mer primers and twelve Eco-RI/Mse-I primer combinations. RAPD fingerprints were not reproducible using the recovered flower template. AFLP fingerprints detected an average of 47 markers and furnished evidence that the recovered flower was genetically different from each of the seized plants. This new type of molecular marker proved to be a powerful tool for discriminating genetic differences even between phenotypically similar pelargonium individuals. AFLP markers could, therefore, be adopted for the granting of Plant Breeders' Rights with the aim of making the protection of new pelargonium cultivars more specific and effective. Because they can detect reliable genetic polymorphisms and supply effective cultivar descriptors, AFLP fingerprinting could be crucial for the future of pelargonium breeding and new cultivar testing.