ABSTRACT
The genus Neocinnamomum is considered to be one of the most enigmatic groups in Lauraceae, mainly distributed in tropical and subtropical regions of Southeast Asia. The genus contains valuable oilseed and medicinal tree species. However, there are few studies on the genus Neocinnamomum at present, and its interspecific relationship is still unclear. In order to explore the genetic structure and evolutionary characteristics of the Neocinnamomum chloroplast genome and to resolve the species relationships within the genus, comparative genomic and phylogenetic analyses were performed on the whole chloroplast genome sequences of 51 samples representing seven Neocinnamomum taxa. The whole Neocinnamomum chloroplast genome size ranged from 150,753-150,956 bp, with a GC content of 38.8%-38.9%. A total of 128 genes were annotated within the Neocinnamomum chloroplast genome, including 84 protein coding genes, 8 rRNA genes, and 36 tRNA genes. Between 71-82 SSRs were detected, among which A/T base repeats were the most common. The chloroplast genome contained a total of 31 preferred codons. Three highly variable regions, trnN-GUU-ndhF, petA-psbJ, and ccsA-ndhD, were identified with Pi values > 0.004. Based on the whole chloroplast genome phylogenetic tree, the phylogenetic relationships among the seven Neocinnamomum taxa were determined. N. delavayi and N. fargesii were the most closely related species, and N. lecomtei was identified as the most basal taxon. In this study, the characteristics and sequence variation of the chloroplast genomes of seven Neocinnamomum taxa were revealed, and the genetic relationship among the species was clarified. The results of this study will provide a reference for subsequent molecular marker development and phylogenetic research of Neocinnamomum.
ABSTRACT
Brassaiopsis angustifolia K.M. Feng belongs to the family Araliaceae, and is an endangered shrub species in southwest China. Despite the importance of this species, the plastid genome has not been sequenced and analyzed. In this study, the complete plastid genome of B. angustifolia was sequenced, analyzed, and compared to the eight species in the Araliaceae family. Our study reveals that the complete plastid genome of B. angustifolia is 156,534 bp long, with an overall GC content of 37.9%. The chloroplast genome (cp) encodes 133 genes, including 88 protein-coding genes, 37 transfer RNA (tRNA) genes, and eight ribosomal RNA (rRNA) genes. All protein-coding genes consisted of 21,582 codons. Among the nine species of Araliaceae, simple sequence repeats (SSRs) and five large repeat sequences were identified with total numbers ranging from 37 to 46 and 66 to 78, respectively. Five highly divergent regions were successfully identified that could be used as potential genetic markers of Brassaiopsis and Asian Palmate group. Phylogenetic analysis of 47 plastomes, representing 19 genera of Araliaceae and two related families, was performed to reconstruct highly supported relationships for the Araliaceae, which highlight four well-supported clades of the Hydrocotyle group, Greater Raukaua group, Aralia-Panax group, and Asian Palmate group. The genus Brassaiopsis can be divided into four groups using internal transcribed spacer (ITS) data. The results indicate that plastome and ITS data can contribute to investigations of the taxonomy, and phylogeny of B. angustifolia. This study provides a theoretical basis for species identification and future biological research on resources of the genus Brassaiopsis.
Subject(s)
Araliaceae , Genome, Chloroplast , Genome, Plastid , Chloroplasts/genetics , Humans , Microsatellite Repeats/genetics , PhylogenyABSTRACT
Eriobotrya bengalensis (Roxb.) is a subtropical plant under the family Rosaceae with high economic and medicinal value. The whole chloroplast genome of E. bengalensis was sequenced to better understand its phylogenetic position relative to other Rosaceae species. The total length of the E. bengalensis chloroplast genome was 159,270 bp, which was composed of a large single-copy (LSC) region of 87,362 bp, a small single-copy (SSC) region of 19,184 bp, and a pair of inverted repeats (IRs) with a length of 26,362 bp separated by LSC and SSC. The total G + C content of the whole chloroplast genome was 36.7%. Phylogenetic analysis of maximum likelihood (TVM + F+R2) was completed using 15 complete chloroplast genomes of Rosaceae species. The results of phylogenetic analysis show that sisterhood exists in E. bengalensis with nine other species of Eriobotrya.
ABSTRACT
The genus Pyrus, comprising several popular fruit crops worldwide, includes over 30 tree species. Here we determined the complete plastid genome sequence of Pyrus betulaefolia. The plastome consists of 160,184 bp, including a pair of inverted repeats (IRs) with a length of 26,384 bp separated by a large single-copy region (LSC) and a small single-copy region (SSC) of 88,121 bp and 19,295 bp, respectively. Further phylogenetic analyze was conducted using 11 complete plastid genomes of Rosaceae with KVM + F + I model, which supports Pyrus betulaefolia as a sister to all other eight Pyrus taxa with published plastomes.
ABSTRACT
Illigera celebica is an evergreen woody vine that belongs to genus Illigera Bl in the family Hernandiaceae and has medicinal value. The complete chloroplast genome of I. celebica was sequenced to determine its phylogenetic location with respect to the other species under the Laurales. Its whole chloroplast genome is 156,123 bp in length, and comprises a large single-copy region (LSC, 84,913 bp), a small single-copy region (SSC,18,775 bp), and a pair of inverted repeats (IRs, 26,217 bp). The overall GC content is 39.2% (LSC, 37.8%; SSC, 33.9%; IR, 43.4%). Maximum likelihood phylogenetic analysise (TVM + F + R2 model) was conducted using 15 complete chloroplast genomes of Laurales, and the results confirmed that Hernandia nymphaeifolia and Wilkiea huegeliana were located in the same lineage.
