Randomly amplified polymorphic DNA analysis for establishing phylogenetic relationship among Cattleya walkeriana Gardn., Cattleya nobilior Rchb. f. and Cattleya loddigesii Lindl.

Abstract

Twenty five varieties of Cattleya walkeriana, including one with an obscure original source and phylogenetically unidentified, C. nobilior, C. loddigesii, and their hybrids, were examined by RAPD analysis in an attempt establish their phylogenetic relationships and to distinguish varieties with different flower colors. Eight 12- and 10- mer primers generated 176 polymorphic bands between 100 and 2000 bp, out of which 65 bands were used for cluster analysis. Three dinstinct clusters representing C. walkeriana, C. nobilior and C. loddigesii were obtained, indicating that C. nobilior was clearly a different species from C. walkeriana in accordance with the classification of Brieger et al. (1981). C. walkeriana var. alba 'Pendentive' is a presumed variety of C. nobilior or a hybrid of C. loddigesii, but fell into the same cluster as other varieties of C. walkeriana var. alba. C. walkeriana varieties with different flower colors were distributed into different clusters by RAPD analysis when only one primer was used.