A plastome is the genome of a plastid, a type of organelle found in plants and in a variety of protoctists. The number of known plastid genome sequences grew rapidly in the first decade of the twenty-first century. For example, 25 chloroplast genomes were sequenced for one molecular phylogenetic study.[1]
The flowering plants are especially well represented in complete chloroplast genomes. As of January, 2017, all of their orders are represented except Commelinales, Picramniales, Huerteales, Escalloniales, Bruniales, and Paracryphiales.
A compilation of most complete plastid genomes is maintained by the NCBI in a public repository.[2]