Molecular phylogeny of Dipterocarpaceae in Indonesia based on chloroplast DNA

Abstract

In order to construct a molecular phylogeny of Indonesian Dipterocarpoideae (Dipterocarpaceae), PCR-RFLP of the chloroplast regions rbcL, petB, psbA, psaA, and trnL-F was performed with seven restriction enzymes in 129 samples including 58 species from nine genera. In the strict consensus tree with Monotes kerstingii as outgroup Indonesian Dipterocarpaceae were divided into two major clades. One clade (bootstrap value=71) consisted of Upuna, Cotylelobium, Anisoptera, Vatica, Dipterocarpus (tribe Dipterocarpeae, bootstrap value=83) and Dryobalanops (tribe Shoreae, bootstrap value=99) in a basal position. The second clade consisted of Hopea, Parashorea, and Shorea (tribe Shoreae) with 95% bootstrap support. Tribe Dipterocarpeae is monophyletic, tribe Shoreae is polyphyletic since Dryobalanops is sister to tribe Dipterocarpeae. In the neighbour-joining tree the sister group position of Dryobalanops to tribe Dipterocarpeae is not supported by the bootstrap analysis. Alternatively, we used Upuna borneensis as outgroup. The effect of outgroup selection on tree topology, taxonomic classification and the interpretation of character evolution is discussed.