Characterization of the chloroplast genome of Verbena officinalis Linn. (Verbenaceae) and its phylogenetic analysis

Verbena officinalis has a long history as a source plant in traditional Chinese medicine. This study adopted next-generation sequencing technology in order to determine complete chloroplast genome of V. officinalis. The results of this investigation showed the chloroplast genome of V. officinalis was 153,286 bp in length, including a pair of inverted repeat (IR) regions (each 25,825 bp), separated by a large single-copy region (LSC) of 84,316 bp and a small single-copy region (SSC) of 17,320 bp, and the overall GC contents of the chloroplast genome was 39.04%. Additionally, we annotated 83 genes, including 48 protein-coding genes, 31 tRNA genes, and 4 rRNA genes. By creating the phylogenetic tree, relationship between V. officinalis and relevant species was discussed, and the result proved that V. officinalis was closely related to Avicennia marina. The findings of the study will serve as a stepping stone for follow-up researches regarding its chloroplast genome.