Complete Chloroplast Genome Sequences and Phylogenetic Analysis of Three Camellia oleifera Cultivars

摘要

Camellia oleifera is an economically important edible oil tree that is cultivated over an area of about 4.3 million hectares in outhern China. To elucidate the molecular and evolutionary characteristics of C. oleifera chloroplasts, we sequenced and characterized its genome using Illumina high-throughput sequencing (HiSeq) combined with third-generation PacBio sequencing technology. The chloroplast genomes ranged from 156,965 to 156,975 bp, containing 133 genes including 8 rRNAs, 37 tRNAs and 88 protein-coding genes, and had a typical quadripartite structure with conserved genome arrangement. Approximately 50 simple sequence repeats (SSRs) and 37 repeat sequences were identified in the C. oleifera chloroplast genome. A comparison with seven other Camellia complete chloroplast genomes detected only slight differences in the coding regions of some genes, including psbN and ycf1; highly divergent regions were observed in the intergenic spacers (IGS) of the 10 Camellia chloroplast genomes. Phylogenetic analysis suggested a sister relationship among three C. oleifera cultivars (?Huashuo?, ?Huajin? and ?Huaxin?) and C. oleifera, whereas C. oleifera from Hainan was identified as sister to C. azalea. Based on our evaluation of the chloroplast genomic resources of three C. oleifera cultivars, we assembled the complete chloroplast genomes; the development of abundant C. oleifera genetic resources will contribute to further studies of genetic engineering, phylogeny, and evolution among family Theaceae species.