Annals of Botany 84: 253-257, 1999
© 1999 Annals of Botany Company
Random Amplified Polymorphic DNA Variation among and within Selected Ixora (Rubiaceae) Populations and Mutants
Department of Biological Sciences, The National University of Singapore, 3 Science Drive 2, Singapore, 117543 Singapore Botanic Gardens, Conservation Unit, National Parks Board, 1 Cluny Road, Singapore, 259569 Herbarium, Forest Research Institute Malaysia, 52109, Kepong, Kuala Lumpur, Malaysia
February 10, 1999 ; April 7, 1999 . May 3, 1999
Random amplified polymorphic DNA (RAPD) analysis was used to study variation among and within selectedIxora (Rubiaceae) populations and mutants. Six populations of I. congesta yielded identical banding patterns suggesting genetic uniformity of this species. However, six populations of I. coccinea varieties (three red-flowered, two yellow-flowered and one red-flowered wild-type) exhibited infraspecific differences in RAPD profiles. Small and large leaves of an atavistic mutant cultivar of I. coccinea were also subjected to RAPD analysis. An extra band was amplified in the large leaves that was absent in small leaves, suggesting that the phenotypic alteration in this taxon is due to genetic mutation rather than epigenetic changes. Similarly, an extra band was detected in the white sectors of I. Variegated compared to the green sectors, suggesting that the shoot apical meristems of this cultivar exist as a genetic chimera. DNA gel blot hybridization was performed to confirm the specificities of selected bands. Our study indicates that differences among individuals of various populations and mutants may be detected using RAPD markers. Copyright 1999 Annals of Botany Company
Ixora L., variegated variety, RAPD fingerprinting, DNA gel blot, intraspecific genetic similarity, atavistic mutant.