Phylogenetic studies of magnoliids: Advances and perspectives

Abstract

Magnoliids are the largest flowering plant clades outside of the eudicots and monocots, which are distributed worldwide and have high economic, ornamental and ecological values. Eudicots, monocots and magnoliids are the three major clades of Mesangiospermae, and their phylogenetic relationship is one of the most interesting issues. In recent years, with the continuous accumulation of genomic information, the evolutionary status of magnoliids has become a hot spot in plant phylogenetic research. Although great efforts have been made to study the evolution of magnoliids using molecular data from several representative species such as nuclear genome, plastid genome, mitochondrial genome, and transcriptome, the results of current studies on the phylogenetic status of magnoliids are inconsistent. Here, we systematically describe the current understanding of the molecular research on magnoliid phylogeny and review the differences in the evolutionary state of magnoliids. Understanding the research approaches and limitations of magnoliid phylogeny can guide research strategies to further improve the study of the phylogenetic evolution of magnoliids.

Characterization of the Complete Mitochondrial Genome of Wintersweet (Chimonanthus praecox) and Comparative Analysis within Magnoliids

“…Unfortunately, only a few mitochondrial genome sequences in magnoliids are currently available. Only eleven magnoliids mitochondrial genomes were downloadable from the NCBI website, which is even less than the number of nuclear genomes that have been sequenced [23]. The eleven mitochondrial genomes belong to three orders (Piperales, Magnoliales, and Laurales, lacking Canellales) and five families (Saururaceae, Aristolochiaceae, Magnoliaceae, Calycanthaceae, and Lauraceae), accounting for only 27.78% of the total family number within magnoliids.…”

“…Although more than 23 nuclear genomes from magnoliid species have been reported and great efforts have been taken to study the evolution of magnoliids using molecular data such as nuclear genome, plastid genome, or mitochondrial genome, the current understanding on magnoliids phylogeny is yet inconsistent [22,23]. Thus, mitochondrial genomes, housing the oxidative phosphorylation machinery and many other essential metabolic pathways, may provide additional sophisticated evidence for the phylogenetics of magnoliids [24].…”