| 【Objective】Syzygium acuminatissimum is a high-value hardwood tree species in southern China. It is
suitable to be planted as a street tree or landscape tree. The study revealed the structural characteristics and phylogenetic
relationship of the chloroplast genome of S. acuminatissimum, which will be of great importance for the taxonomic researches
of Syzygium and even Myrtaceae.【Method】The CTAB method was used to extract genomic DNA from the leaves of S.
acuminatissimum. High-throughput sequencing was conducted through the Illumina HiSeq X TEN platform, the chloroplast
genome was assembled on SPAdes v3.13.0, and the complete chloroplast genome of S. acuminatissimum was annotated
on GeSeq. Then, the structural characteristics, sequence characteristics and phylogenetic relationship of the chloroplast
genome of S. Acuminatissimum were analyzed.【Result】The complete chloroplast genome of S. acuminatissimum was
159 352 bp in length, with 109 annotated genes, including 78 protein-coding genes, 27 tRNA genes and 4 rRNA genes,
of which 17 genes had introns. A total of 21 379 codons were detected, of which serine codons were the most abundant
and methionine codons were the least. 47 RNA editable sites were detected, of which the ndhB genes were the most （10）. 48 long repeat sequences were detected, of which 18 were forward repeats, 6 inverted repeats, 22 palindrome repeats
and 2 complementary repeats. 230 simple repeats were detected, most of which were single nucleotides（205）. Results of
genome comparison analysis showed that the IR boundaries of the 4 Syzygium plants were slightly different, and there were 7
regions with nucleotide diversity higher than 0.015. Results of the phylogenetic analysis showed that S. acuminatissimum and
S. aromaticum were closely related. 【Conclusion】The research results will help to carry out the follow-up researches on the
phylogeny and species identification of Syzygium. |
