Sequencing Relationships among Five Species of Hydrocotyle Based on TrnL-TrnF Intergenic Spacer Gene

The objective of this study was to verify nucleotide variation of genus Hydrocotyle. The 389-392 base pairs of the trnL-trnF intergenic spacer of the chloroplast DNA of five Hydrocotyle taxa (H. sibthorpioides, H. ramiflora, H. nepalensis, H. maritima, and H. yabei) were sequenced. The mean nucleotide frequencies for five species of genus Hydrocotyle were A = 35.2%, C = 17.7%, G = 20.0%, and T = 27.1%. Total alignment length of genus Hydrocotyle was 392 positions, of which seven bases were parsimony-informative, 34 variables, 27 singletons, and 358 conserved. Rates of different transitional substitutions were varied from 1.69 to 17.0 and those of transversionsal substitutions were 6.14-12.2. The number of segregating sites of genus Hydrocotyle was 34 and nucleotide diversity (π) was 0.042. Rates of different transitional substitutions were varied from 1.69 to 17.0 and those of transversionsal substitutions were 6.14-12.2. H. sibthorpioides and H. maritima were also close relationship with high bootstrap support value. H. ramiflora, and H. yabei were very distinct in ML tree. The DNA sequences in the trnL intron and the trnL, trnF intergenic spacer are useful for phylogenetic reconstruction in the five species of genus Hydrocotyle.