The complete chloroplast genome of <i>Swertia davidii</i> (gentianaceae) and its phylogenetic analysis

To elucidate the genetic information and evolutionary relationships of <i>Swertia</i>, we initiated the sequencing of the complete chloroplast genome of <i>Swertia davidii</i> Franch. 1888, complemented by comparative analyses with closely related species. The chloroplast genome of <i>S. davidii</i> was 153,516 bp in length and exhibited a typical quadripartite structure. It contained two regions with Inverted Repeat lengths of 25,767 bp, located between one Large Single-Copy region (83,617 bp) and one Short Single-Copy region (18,365 bp). The chloroplast genome of <i>S. davidii</i> encoded 132 genes, including 87 protein-coding genes, 37 transfer RNA genes, and 8 ribosomal RNA genes. The overall GC content was 38.15%. Maximum likelihood phylogenetic analysis of <i>Swertia</i> based on 26 available plastomes showed a close relationship between <i>S. davidii</i> and <i>S. kouitchensi</i>. This study will contribute to the genetic preservation of the species and the phylogenetic study of <i>Swertia</i>.