The chloroplasts genomic analyses of Rosa laevigata, R. rugosa and R. canina

Abstract

Abstract Background Many species of the genus Rosa have been used as ornamental plants and traditional medicines. However, industrial development of roses is hampered due to highly divergent characteristics. Methods We analyzed the chloroplast (cp) genomes of Rosa laevigata, R. rugosa and R. canina, including the repeat sequences, inverted-repeat (IR) contractions and expansions, and mutation sites. Results The size of the cp genome of R. laevigata, R. rugosa and R. canina was between 156 333 bp and 156 533 bp, and contained 113 genes (30 tRNA genes, 4 rRNA genes and 79 protein-coding genes). The regions with a higher degree of variation were screened out (trnH-GUU, trnS-GCU, trnG-GCC, psbA-trnH, trnC-GCA,petN, trnT-GGU, psbD, petA, psbJ, ndhF, rpl32,psaC and ndhE). Such higher-resolution loci lay the foundation of barcode-based identification of cp genomes in Rosa genus. A phylogenetic tree of the genus Rosa was reconstructed using the full sequences of the cp genome. These results were largely in accordance with the current taxonomic status of Rosa. Conclusions Our data: (i) reveal that cp genomes can be used for the identification and classification of Rosa species; (ii) can aid studies on molecular identification, genetic transformation, expression of secondary metabolic pathways and resistant proteins; (iii) can lay a theoretical foundation for the discovery of disease-resistance genes and cultivation of Rosa species.

Keywords

• Rosa species
• cp genome
• Phylogeny