Analysis of genetic relationships of Central American and Mexican pines using RAPD markers that distinguish species

Phylogenetic relationships were inferred for six Central American and Mexican pine species by analysing RAPD marker differences among pooled DNA samples. This population level pooling strategy discounts low-frequency allelic variation within taxa, thus obtaining a ‘cumulative genotype’ to compare among taxa. We used the morphologically based taxonomy of pines as the basis for inference concerning molecular marker divergence. Only RAPD polymorphisms that were repeatable and intensely amplified were used. The resulting data set was found to have strong hierarchical structure. Phylogenetic analyses were carried out using both neighbour-joining and maximum parsimony. The phylogenetic relationships indicated by analysis of the pine RAPD data provide new insights on pine taxonomy. The phylogenetic analyses of the RAPD marker data placed Pinus tecunumanii and P. patula clearly into two different subgroups, strongly supporting the classification of P. tecunumanii as a distinct species, and raise a new set of issues concerning the distinctions between Pinus tecunumanii and P. caribaea. Phylogenetically informative RAPD markers will be useful tools to address ex-situ conservation issues that involve taxonomic identification and species admixture.