Complete chloroplast genome sequences of three aroideae species (Araceae): lights into selective pressure, marker development and phylogenetic relationships

Background: Colocasia gigantea, Caladium bicolor and Xanthosoma sagittifolium are three worldwide famous ornamental and/or vegetable plants in the Araceae family, these species in the subfamily Aroideae are phylogenetically perplexing due to shared interspecifc morphological traits and variation. Result: This study, for the frst time ever, assembled and analyzed complete chloroplast genomes of C. gigantea, C. bicolor and X. sagittifolium with genome sizes of 165,906bp, 153,149bp and 165,169bp in length, respectively. The genomes were composed of conserved quadripartite circular structures with a total of 131 annotated genes, including 8 rRNA, 37 tRNA and 86 protein-coding genes. A comparison within Aroideae showed seven protein-coding genes (accD, ndhF, ndhK, rbcL, rpoC1, rpoC2 and matK) linked to environmental adaptation. Phylogenetic analysis confrmed a close relationship of C. gigantea with C. esculenta and S. colocasiifolia, and the C. bicolor with X. sagittifolium. Furthermore, three DNA barcodes (atpH-atpI+psaC-ndhE, atpH-atpI+trnS-trnG, atpH-atpI+psaC-ndhE+trnS-trnG) harbored highly variable regions to distinguish species in Aroideae subfamily. Conclusion: These results would be benefcial for species identifcation, phylogenetic relationship, genetic diversity, and potential of germplasm resources in Aroidea