Complete plastid genome of Angelica, Ostericum and related species (Apiaceae): genomic evolution and phylogenetic implications

Abstract Background Subtribe Angelicinae is a large and taxonomically complex group of Apiaceae, encompassing Angelica , Archangelica , Coelopleurum , Conioselinum , Czernaevia , Glehnia , Levisticum and Ostericum that are distributed in the Northern Hemisphere, and whether this taxa is natural is debatable, especially between Angelica and Ostericum . To determine genommic evolution and phylogenetic relationships between Angelica , Ostericum , and related species, we newly assembled the complete plastid genome sequences of eight subtribe Angelicinae species and Melanosciadium pimpinelloideum using next-generation sequencing technology. Results The nine plastid genomes we sequenced were conserved, and their size ranged from 146765 bp to 164329 bp, showing the typical quadripartite circular structure with an overall GC content of 37.5–37.8%. IR boundary analyses showed that the genes in the LSC region transfer into the IR regions and the SSC region was relatively stable. Codon usage patterns were similar among these species and we identified 66–86 SSRs, with the most abundant SSR being mononucleotide. The Pi analyses showed that petA-psbJ (0.02778), atpI-atpH (0.17333) and petA-psbJ (0.04726) intergenic regions had the highest Pi values in Angelica , Ostericum , and ten species, respectively. Conclusions Ostericum exhibited significant differences in size of genomes, content of genes and tRNAs, GC content, some type of SSRs, and IR boundaries to Angelica , and phylogenetic analyses found the relatedness between Angelica and Ostericum is more distant in protein-coding genes of the plastid genomes trees and nrITS trees.