Genetic analyses of Heliconia species and cultivars with randomly amplified polymorphic DNA (RAPD) markers

Abstract

Many Heliconia species are polymorphic with a large number of cultivars. Cultivar identification has been primarily based on morphological differences of the flowers and inflorescences. A protocol was developed to extract DNA from Heliconia leaves and to analyze genetic variation using RAPD. The percentage genetic similarities among Heliconia species, cultivars, and hybrids were determined. Data from 11 primers indicated that the RAPD technique is useful in distinguishing species and cultivars of Heliconia. Using a single 10-mer primer (OPA18), we were able to generate distinct RAPD profiles for 16 cultivars of H. psittacorum L.f. grown at the Jurong BirdPark, Singapore, a Heliconia Society International depository. Hence, the characteristic profiles generated by RAPD may be used as additional DNA markers for classifying different species and cultivars of Heliconia. The phylogenetic tree derived from the RAPD data showed that all the 16 cultivars examined are closely related to each other, thus providing the first genetic evidence that this large group of cultivars has a common genetic background. Moreover, two triploid cultivars of H. psittacorum - 'Iris' and 'Petra'-showed identical RAPD profiles with 10 different primers in agarose and polyacrylamide gels, suggesting that they are of the same genotype.