Complete chloroplast genome of the Jewel Orchid, Anoectochilus formosanus (Orchidaceae) and its relatives

Abstract

Introduction: Anoectochilus formosanus is a highly valuable herb known for its efficacy in treating a wide range of diseases. However, the current methods used to differentiate this species from others within the same genus are not effective due to the high similarity in morphological characteristics and DNA barcode sequences among these species. Objective: Characterization of chloroplast (cp) genome in order to identify potential molecular markers to distinguish this plant at species or isolation levels is necessary. Methods: The complete cp genome was sequenced using next-generation sequencing technology, annotated, and compared with published cp genomes of various species within the Anoectochilus genus. Results: The complete cp genome of A. formosanus is 152 658 bp in size, consisting of a large and small copy of 82 692 bp and 17 346 bp, respectively, separated by reverse repeats of 26 310 bp. Within the cp genome, there are a total of 141 genes, including 92 protein-coding genes, 10 rRNA genes, and 39 tRNA genes. This genome contains a total of 80 simple sequence repeats, with 50 long repeats. Through phylogenetic analysis, a close relationship was observed between A. formosanus in Vietnam and A. formosanus samples originated from China (NC_061756.1). However, genomic comparisons highlighted significant differences between the two cp genomes, specifically in their reverse repeat sequences. Conclusions: These findings reveal distinct variations in the cp genome of A. formosanus in Vietnam, offering valuable insights for the taxonomy, plant identification, breeding, and conservation programs related to this herb in Vietnam.