Phylogenetic Analysis of Primula Chloroplast Genomes

The genus Primula, comprising over 500 species of temperate and alpine herbs, presents taxonomic and evolutionary challenges owing to frequent hybridisation, heterostyly and morphological convergence. Chloroplast genome sequencing offers a powerful tool to resolve interspecific relationships by providing genome-scale markers, such as coding regions, intergenic spacers and repeat motifs. Comparative analyses reveal conserved genome architecture—typically a circular quadripartite structure of large and small single-copy regions separated by inverted repeats—yet also highlight divergence hotspots that underpin phylogenetic signal. Integrating chloroplast phylogenomics with morphological data has refined our understanding of clade delimitation, monophyly of sections and historical biogeography across Eurasia. Such insights bear practical implications for species conservation, breeding programmes and elucidation of speciation processes in a genus of ecological and horticultural importance.

Research from Nature Portfolio

Recent studies have sequenced and analysed the chloroplast genomes of several pinnate-leaved Primula species, establishing genome sizes of approximately 150–152 kilobases and identifying a consistent set of 113 genes. Investigations of sequence synteny, inverted-repeat boundaries and pseudogenisation events have underscored structural conservation, while the detection of simple sequence repeats and highly variable regions—most notably ycf1 in coding sequences and trnH-psbA in noncoding regions—has facilitated resolution of phylogenetic relationships. These analyses have delineated two principal clades and supported taxonomic reassignment of species within the group, demonstrating the utility of chloroplast markers in clarifying evolutionary affinities.

Phylogenetic Analysis of Primula Chloroplast Genomes publication trend

The graph below shows the total number of articles in phylogenetic analysis of primula chloroplast genomes across all publications each year (not limited to Nature Index journals).

Technical terms

Chloroplast genome: The complete DNA sequence contained within the chloroplast, often exhibiting a four-part circular organisation.

Inverted repeat (IR): A duplicated sequence region in chloroplast genomes that separates the large and small single-copy regions.

Simple sequence repeat (SSR): A short, tandemly repeated DNA motif often used as a molecular marker for genetic variation.

Divergence hotspot: A genomic region exhibiting elevated levels of sequence variation useful for phylogenetic inference.

Monophyly: The condition of a group of organisms consisting of all the descendants of a common ancestor.

Introgression: The incorporation of genetic material from one species into the gene pool of another through hybridisation and backcrossing.

Phylogenetic analysis: A methodological framework for reconstructing evolutionary relationships among taxa using genetic or morphological data.

References

1. Comparative Plastid Genomes of Primula Species: Sequence Divergence and Phylogenetic Relationships. International Journal of Molecular Sciences (2018).
2. The complete chloroplast genome sequences of five pinnate-leaved Primula species and phylogenetic analyses. Scientific Reports (2020).
3. Comparative analysis of chloroplast genomes of endangered heterostylous species Primula wilsonii and its closely related species. Ecology and Evolution (2023).
4. The Complete Chloroplast Genomes of Primula obconica Provide Insight That Neither Species nor Natural Section Represent Monophyletic Taxa in Primula (Primulaceae). Genes (2022).