Abstract
Keteleeria davidiana Beissn. var. formosana Hay. distributes disjunctively in Taiwan. Jiau-Shi nature preserves and Ping-Lin nature reserves are located in northern Taiwan and Ta-Wu nature preserve is located in southern Taiwan. This native species is currently protected by Taiwan Forest Bureau due to its scarce population and low ratio of seed setting. This study was to investigate the genetic divergence between these two disjunctive populations using RAPD markers resulted from genetic variation and variation in nuclear ribosomal DNA. To analyze the genetic divergence among 102 plants of this species, 17 synthetic oligonucleotides were used to obtain RAPD markers. According to the phylogenetic tree, the samples were clustered into four groups. Group A includes Jiau-Shi Compartment 24 and 25 and Ping-Lin Compartment 40 and 41; group B includes Ta-Wu Compartment 41; group C includes Da-Wu Compartment 30 and group D includes Da-Zen Ridges 1 and 2. Our result indicates that the genome of population in northern Taiwan is different from that in southern Taiwan, corresponding to the disjunct distribution of this species. In the ITS genetic divergence study, three clones of plant 66 in Jiau-Shi Compartment 24 and one clone of plant 6 in Compartment 25 were obtained. The ITS sequences obtained from an individual plant share similarities of 99% or more, the similarity of ITS between different plants was about 95%. Both the neighbor-joining and maximun parsimony trees showed that the K. davidiana Beissn. var. formosana Hay. and 14 Pinaceae plants can be divided into four groups. Our results suggest the importance of protecting and re-establishing the population of this species due to the genetic divergence among K. davidiana Beissn. var. formosana Hay. individuals.