Research on genetic diversity and genomes of Miscanthus for optimizing their biotechnological potential.

Abstract

Plants of the genus Miscanthus are a promising perennial energy crop, combining high biomass productivity, resistance to abiotic stress, and low agricultural technology requirements. This review summarizes recent advances in genomic and transcriptomic studies of the molecular genetic mechanisms underlying the economically valuable traits of Miscanthus. Data on whole-genome assemblies of key species - M. sinensis (Msi), M. sacchariflorus (Msa), M. floridulus (Mfl), and M. lutarioriparius (Mlu) - are presented using various technologies (Illumina, PacBio, Oxford Nanopore, Hi-C). Genomic studies have revealed the complex evolution of the genus, including paleoallopolyploidy, chromosomal fusions, and duplications, which accounts for the high genetic diversity of these species. Their genome assemblies at the complete chromosome level have become the basis for comparative genomics, establishing taxonomic relationships (including the recognition of Mlu as a subspecies of Msa and Mfl as a subtype of Msi), and studying synteny with related crops such as sorghum. The information on the Miscanthus genome allows for the complete and accurate identification of a set of genes targeting breeding for the most important biotechnological traits. At the same time, the commercial hybrid M. × giganteus (M × g) is characterized by extremely low levels of genetic polymorphism, making it vulnerable to pathogens and climate fluctuations. The integration of genetic polymorphism data, phylogeography, and functional annotation of genomes opens up opportunities for the development of new, productive, and environmentally friendly Miscanthus varieties through interspecific crossings, ploidy modification, and genetic engineering. These advances contribute to the optimization of the biotechnological potential of Miscanthus for the production of biofuels and other biomaterials and the restoration of degraded lands.