The complete chloroplast genome sequences of the Rosa kokanica (Regel) Regel ex Juz. (Rosaceae).

Rosa kokanica is a deciduous shrub distributed in Central Asia. We determined the genomic characteristics of the complete chloroplast genome in R. kokanica with a de novo assembly strategy. The chloroplast genome was 156,802bp in length harboring 89 protein coding genes, 37 tRNA genes and eight rRNA genes. It exhibits typical quadripartite structure comprising a large single-copy (LSC) (85,899bp), a small single-copy (SSC) (18,773bp) and a pair of inverted repeats (IRs) (26,065bp). Phylogenetic analysis of 16 chloroplast genomes from Rosaceae revealed that the genus Rosa is a monophyletic group and the R. kokanica is clustered together with the congener, R. acicular.

Rosa kokanica (Regel) Regel ex Juz. (Rosaceae) is a deciduous shrub distributed in high mountain slopes of Central Asia including Afghanistan, China (Xinjiang), Iran, Kazakhstan, Kyrgyzstan, Pakistan, Tadzhikistan and Uzbekistan (Gu and Robertson 2003). Genus Rosa is well known for its economic importance as ornamental and medicinal plants (Raymond et al. 2018). R. kokanica, which is one of ca. 30 Rosa taxa distributed in Central Asia, has been widely used for medicines, and has potential ornamental values (Tolekova et al. 2020). However, the genomic information applicable for Central Asian Rosa is still scarce. In the present study, we investigated the genomic architecture in the whole chloroplast genome of R. kokanica using whole genome shotgun sequencing.

We collected young leaves of R. kokanica from Namangang province, Uzbekistan (N 41°01′43.4″, E 70°36′27.5″). The voucher specimen was prepared and deposited at the Herbarium of Korea National Arboretum (KH) with the accession number KHB1547488. The total genomic DNA was extracted followed by manufacturer’s protocol (Qiagen, Hilden, Germany). After library preparation, the prepared libraries were sequenced on Illumina MiSeq platform (Illumina, San Diego, CA). Seven million high-quality 300 bp paired-end reads were obtained. We assembled 2.19GB reads with de novo strategy using Geneious Prime (ver. 4.2.1) according to the manufacturer’s instruction. The genes were predicted with GeSeq (Tillich et al. 2017), and manually curated based on Blast search result. The simple sequence repeats were investigated with MISA (Beier et al. 2017).

The complete chloroplast genome of R. kokanica has been submitted to Genbank (accession no. MW298478). It is 156,802bp in length with the typical quadripartite structure comprising a large single copy (LSC) (85,899bp), a small single-copy (SSC) (18,773bp) and a pair of inverted repeats (IRs) (26,065bp). The chloroplast genome contained 131 genes including 89 protein coding genes, 37 tRNA genes and eight rRNA genes. 51 simple sequence repeats were identified in the cp genome, most of which was mono-nucleotide repeat.

To investigate its phylogenetic relationship, the concatenated CDs sequences from entire chloroplast genome of 16 Rosa and outgroup taxa were aligned in MAFT (Katoh et al. 2019). All sequences except R. kokanica were downloaded from NCBI Genbank. We assigned Dasiphora and Fragaria as an outgroup following phylogenetic relationships based on a previous study (Potter et al. 2007). We inferred the phylogeny using Maximum likelihood (ML) algorithm implemented in RAxML v. 4.0 with GTR GAMMA model. For the clade support, 1000 bootstrap replicates were used. The 13 species of Rosa formed a monophyletic group (BP = 100) with strong support on ML tree (Figure 1). In ML tree, section Pimpinellifoliae did not form a monophyletic group, which is consistent with previous phylogenetic studies (Fougère-Danezan et al. 2015). The ML tree also indicated that R. kokanica is most closely related with R. acicularis.

Figure 1.

Maximum Likelihood (ML) tree based on chloroplast genome sequences of 16 species of Rosaceae, numbers on the nodes indicated the bootstrap support value (>50%).