Assembly and Analysis of the Complete Mitochondrial Genome of Eryngium foetidum L. (Apiaceae)

Eryngium foetidum L. belongs to the Apiaceae family and is a perennial herb. The entire plant is rich in essential oils, which have a distinctive aroma similar to cilantro. This plant exhibits significant biological activity and possesses characteristics such as disease resistance and antimicrobial properties, showing great potential in medical and food applications. Additionally, its essential oil has substantial commercial value. Mitochondria play a crucial role as organelles within plant cells; however, the mitochondrial genome of E. foetidum remains underexplored. To fill this research gap, we conducted sequencing and assembly of the mitochondrial genome of E. foetidum, aiming to uncover its genetic mechanisms and evolutionary trajectories. Our investigation reveals that the mitochondrial genome of E. foetidum is a circular structure, similar to that of other species, with a length of 241,660 bp and a GC content of 45.35%, which is within the range observed in other organisms. This genome encodes 59 genes, comprising 37 protein-coding sequences, 18 tRNA genes, and 4 rRNA genes. Comparative analysis highlighted 16 homologous regions between the mitochondrial and chloroplast genomes, with the longest segment spanning 992 bp. By analyzing 37 protein-coding genes (PCGs), we identified 479 potential RNA editing sites, which induce the formation of stop codons in the nad3 and atp6 genes, as well as start codons in the ccmFC, atp8, nad4L, cox2, cox1, and nad7 genes. Meanwhile, the genome shows a preference for A/T bases and A/T-ending codons, with 32 codons having a relative synonymous codon usage (RSCU) value greater than 1. The codon usage bias is relatively weak and mainly influenced by natural selection. Most PCGs are under purifying selection (Ka/Ks < 1), while only a few genes, such as rps7 and matR, may be under positive selection. Phylogenetic analysis of mitochondrial PCGs from 21 species showed E. foetidum at the basal node of Apiaceae, consistent with the latest APG angiosperm classification and chloroplast genome-based phylogenetic relationships. In summary, our comprehensive characterization of the E. foetidum mitochondrial genome not only provides novel insights into its evolutionary history and genetic regulation but also establishes a critical genomic resource for future molecular breeding efforts targeting mitochondrial-associated traits in this economically important species.