REVEALING GENETIC-MARKERS IN GELIDIUM-VAGUM (RHODOPHYTA) THROUGH THE RANDOM AMPLIFIED POLYMORPHIC DNA (RAPD) TECHNIQUE

The recently developed random amplified polymorphic DNA technique was evaluated as a method for characterizing isolates of the agarophyte Ge lidium vagum Okamura. Reaction conditions for single primer polymerase chain reaction were optimized to obtain a high degree of reproducibil ity of the amplified bands generated from purified G. vagum DNA. A tot al of 165 primers, including both (A + T)- and (G + C)-rich sequences, was screened for DNA amplification using template DNA from a single G elidium isolate. None of the 45 (A + T)-rich primers was positive (i.e . band-producing). Of the (G + C)-rich primers, 47 were positive, gene rating a total of 322 prominent amplification products for DNA from 13 different G. vagum isolates. Polymorphic DNA loci were detected by 37 of the primers. Unweighted pair-group arithmetic average cluster anal ysis (UPGMA) of these loci was used to group the G. vagum isolates and thereby determine which were most similar. G. latifolium, used as an out-group for the UPGMA analysis, showed a high degree of dissimilarit y.