The first complete chloroplast genome in Engelhardia sensu stricto, Engelhardia hainanensis Chen: genome characterization and its phylogenetic relationships within the family Juglandaceae

Abstract

Trees of Engelhardia are important components of subtropical and tropical forests in South-eastern Asia with great ecological and economic values. However, phylogenetic relationships within Engelhardioideae (Juglandaceae) remains obscure. In this study, we report the first complete chloroplast genome sequences of Engelhardia sensu stricto, Engelhardia hainanensis Chen, a rare species endemic in southern China. Its complete chloroplast genome is 161,574 bp in length, with a typical quadripartite structure that includes a large single-copy region of 91,158 bp, a small single-copy region of 18,790 bp, and its GC content is 35.8%. A total of 128 genes were identified, including 83 protein-coding genes, 37 tRNA genes, and 8 rRNA genes. Furthermore, a phylogenetic tree of Juglandaceae was constructed based the complete chloroplast genome sequence, which strongly support the three-subfamily classification system in Juglandaceae, and E. hainanensis was resolved sister to two Alfaropsis species. This study provides valuable genomic information for the species identification and phylogenetic study of Juglandaceae.

Keywords:

• Alfaropsis
• complete chloroplast genome
• Engelhardia hainanensis
• Juglandaceae

Ethical approval

This study includes no endangered plant samples, and the sampling site is not located in any protected area. The collection of plant materials is in accordance with local regulations and obtain the permission of local authorities.

Author contributions

XYM conceived and designed the work. XYM and YHQ performed field collection and identification of plant material. XYM and YMW assembled and annotated the plastome sequence. YMW prepared genome sequences, performed phylogenetic analysis, and visualized figures. XYM and YMW wrote the manuscript. YMW, XYM and YHQ reviewed drafts of the paper. All authors discussed the results, commented on the manuscript, and approved the current version of the manuscript.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

The genome sequence data that support the findings of this study are openly available in GenBank of NCBI at (https://www.ncbi.nlm.nih.gov/) under the accession no. OM302449. The associated BioProject, SRA, and BioSample numbers are PRJNA797548, SRP355546 and SAMN25010399, respectively.

Additional information

Funding

This work was supported by the Natural Science Foundation of China [grant no. 32070235].