We aim to understand how the Land Plants were established and what genomic change shaped current Land Plants.
The group including Land Plants called streptophytes are monophyletic. Organisms in streptophytes but not Land Plants are called streptophyte algae. Six major Lineages namely Mesostigmatophyceae, Chlorokybophyceae, Klebsormidiophyceae, Charophyceae, Coleochaetophyceae, and Zygnematophyceae branched off the Land Plants more than 500 million years ago. Recent phylogenetic analyses indicate that Mesostigmatophyceae and Chlorophyceae are syster groups that comprise the initial branch of strepgtophytes. Klebsormidium, Charophyceae, Coleochaetophyceae, and Zygnematophyceae branched off from Land Plants in this order. Genome information of at least one strain in each lineage except for Coleochaetophyceae are published.
Within Land Plants, three groups of bryophytes namely mosses, liverworts, and hornworts comprise a monophyletic group that diverged with vascular plants.
Given that the best studied plants are in vascular plants, studies on these groups are key to understand the evolution. Molecular genetic methods are established in late 1990's in the moss Physcomitrium patens, in 2010's in the liverworts Marchantia polymorpha. Transformation is established in hornworts and Zygnematophycean algae Closterium sp.