A POLYMORPHIC MICROSATELLITE MARKER FROM THE TROPICAL TREE DRYOBALANOPS LANCEOLATA (DIPTEROCARPACEAE)

Di-nucleotide microsatellites were isolated from a genomic library of a tropical tree species, Dryobalanops lanceolata, in Sarawak, for the purpose of using them as hypervariable genetic markers to study the po llen-mediated gene flow. Among 1600 recombinant clones, in total 20 cl ones gave positive signals when hybridized with oligonucleotides with the three different repeat motifs, GT, CA and CT. Estimations of abund ance of (GT)(n)/(CA)(n) and (GA)(n)/(CT)(n) di-nucleotide repeats in D . lanceolata genome revealed to be one in every 84 kb and 80 kb, respe ctively. Among six sequenced microsatellite loci, one was selected to synthesize PCR primers to amplify the microsatellite. PCR product size of the locus was variable among different individuals, which is attri buted to the different number of di-nucleotide repeats. The same micro satellite genotype was detected in the trunk and canopy of a single la rge tree, indicating the utility of trunk tissue as the source of DNA for the population genetic study of tropical tree species, the canopy of which is usually difficult to approach.