Complete chloroplast genome sequence and phylogenetic analysis of Populus maximowiczii Henry 1913 (Salicaceae Mirb.)

The classification and identification of species in Populus has remained a formidable challenge due to widespread interspecies hybridization. The complete chloroplast genome of Populus maximowiczii was obtained by Illumina high-throughput sequencing technology, with a typical quadripartite structure and 37.0% GC content. The chloroplast genome of P. maximowiczii was 156,892 in length, including a large single-copy region (LSC: 84,988 bp), a small single-copy region (SSC: 16,630 bp), and a pair of inverted repeats (IRs: each 27,637 bp in length). A total of 131 genes were annotated, including 86 protein-coding genes, 37 tRNAs, and 8 rRNAs. The phylogenetic analysis indicated that 43 species belonging to Populus were classified into monophyly, with P. cathayana being the closest relatives to P. maximowiczii. In conclusion, this study provides valuable insights into understanding the phylogeny of Populus.