Genetic diversity of Rhizophora mucronata on the western coast of Timor Island

The mangrove (Rhizophora mucronata) grows on the western coast of Timor Island and is threatened by anthropogenic activities. Because R. mucronata is an important species, a strategy for sustainable development is required. Information on the genetic diversity of the species is essential in order to plan for coastal management and conservation. This study investigates mangrove genetic diversity on the western coast of Timor Island in the Indonesian Archipelago. Mangrove leaf samples were collected from 10 locations. Samples underwent DNA isolation and random amplified polymorphic DNA testing using six primers. The R. mucronata population formed three main groups and 12 subgroups with a similarity coefficient value of 0.42. The genetic proximity among populations is not related to geographical distance. Further analysis suggests that the genetic diversity of R. mucronata on Timor Island can be classified as moderate. The highest degree of genetic diversity was found in Sumlili (Ne = 2.999, Na = 11.167, He = 0.667), whereas the lowest genetic diversity was found in Sulamu (Ne = 2.967, Na = 11.833, He = 0.663). Environmental stress and dry climate conditions might be a factor related to the genetic diversity of the mangrove at a moderate level.