Introduction(<Feature Articles>New model plants; reference materials for post-genome era)

Abstract

Whereas Arabidopsis thaliana has been intensively investigated as a model plant, plants are so diversified to adapt various environmental conditions and also change their properties during breeding processes. Whereas molecular characterization of plant functions and molecular design of crops become more feasible with their genome data obtained by next generation sequencing (NGS) and genome editing technology, such as CRISPR-Cas9, large diversity of plants still needs new reference plants to focus on the specific plant structures and functions as reviewed in this special issue; 1) liverwort (Marchantia polymorpha) as a model to study plant biology based on its simplest genome structure (Kohchi and Nishihama), 2) Brachypodium distachyon, as a model temperate grass for wheat and barley, as well as a model for energy crops such as switchgrass and Miscanthus (Mochida et al.), 3) carnation (Dianthus caryophyllus L.), as a model of ornamental plants, whose studies are often hindered due to their high heterozygosity and polyploidy (Yagi), 4) cassava (Manihot esculenta Crantz) as a model and important tropical tuberous root crop for food security (Utsumi et al.), 5) tomato (Solanum lycoperisicum), as a model of plants that bear fleshy fruits and of plants belonging to Solanaceae family (Aoki). In this introduction, the importance of NGS in emerging model plants is also discussed in California poppy to study plant specific metabolism, such as alkaloid biosynthesis.