A dated phylogeny shows Plio-Pleistocene climates spurred evolution of antibrowsing defences in the New Zealand flora

Characterization and phylogenetic analysis of the chloroplast genome in Elaeocarpus duclouxii

Elaeocarpus duclouxii, an evergreen tree species, is renowned for its fruits rich in flavonoids exhibiting potent antioxidant properties. Despite its significance, the chloroplast genome of this plant has remained unexplored until now. Our study presents the first comprehensive sequencing and analysis of the E. duclouxii chloroplast genome, revealing a circular DNA molecule of 158,148 base pairs. This genome comprises a large single-copy region of 85,700 base pairs, a small single-copy region of 17,672 base pairs, and a pair of inverted repeat regions totaling 27,388 base pairs. The genome encodes 132 genes, including 87 protein-coding genes, 37 transfer RNA genes, and 8 ribosomal RNA genes. Phylogenetic analyses indicate a close evolutionary relationship between E. duclouxii and E. sylvestris. This study not only represents the first phylogenetic investigation of E. duclouxii but also establishes a crucial genomic foundation for future research area such as conservation genetics, evolutionary biology, and potential biotechnological applications.

Phylogenetic relationships, selective pressure and molecular markers development of six species in subfamily Polygonoideae based on complete chloroplast genomes

The subfamily Polygonoideae encompasses a diverse array of medicinal and horticultural plants that hold significant economic value. However, due to the lack of a robust taxonomy based on phylogenetic relationships, the classification within this family is perplexing, and there is also a scarcity of reports on the chloroplast genomes of many plants falling under this classification. In this study, we conducted a comprehensive analysis by sequencing and characterizing the complete chloroplast genomes of six Polygonoideae plants, namely Pteroxygonum denticulatum, Pleuropterus multiflorus, Pleuropterus ciliinervis, Fallopia aubertii, Fallopia dentatoalata, and Fallopia convolvulus. Our findings revealed that these six plants possess chloroplast genomes with a typical quadripartite structure, averaging 162,931 bp in length. Comparative chloroplast analysis, codon usage analysis, and repetitive sequence analysis demonstrated a high level of conservation within the chloroplast genomes of these plants. Furthermore, phylogenetic analysis unveiled a distinct clade occupied by P. denticulatum, while P. ciliinrvis displayed a closer relationship to the three plants belonging to the Fallopia genus. Selective pressure analysis based on maximum likelihood trees showed that a total of 14 protein-coding genes exhibited positive selection, with psbB and ycf1 having the highest number of positive amino acid sites. Additionally, we identified four molecular markers, namely petN-psbM, psal-ycf4, ycf3-trnS-GGA, and trnL-UAG-ccsA, which exhibit high variability and can be utilized for the identification of these six plants.

The complete chloroplast genome of a fast-growing tree Lophostemon confertus (Myrtaceae)

Lophostemon confertus (Myrtaceae), a fast-growing ornamental tree, is widely cultivated in tropical and subtropical regions. To determine its phylogenetic position within Myrtaceae, here we report its complete chloroplast (cp) genome, which is 160,297 bp long and contains two inverted repeats (IRs) of 26,490 bp each, separated by a small single-copy region of 18,826 bp and a large single-copy region of 88,491 bp. The cp genome contains 123 genes, including 73 unique protein-coding genes (six duplicated in the IR regions), 29 unique tRNA genes (seven duplicated in the IR regions), and four unique rRNA genes (all located in the IR regions). Phylogenetic analysis of 18 species of Myrtaceae showed that L. confertus is sister to Xanthostemon chrysanthus. The complete cp genome of L. confertus provides a valuable genetic resource for further phylogenetic studies.