An Integrative Review of the Genus Onobrychis: Biological Characteristics, Economic Importance, and Multilevel Taxonomic Tools

The genus Onobrychis is a plant genus comprising many important forage species cultivated in different regions of the world, particularly for their good forage quality, drought resistance, and contribution to sustainable agriculture. This review summarizes general information about the biological characteristics, economic importance, and taxonomic structure of the genus by combining different approaches. First, the growth conditions and phenology of Onobrychis species are discussed. Morphological characteristics commonly used to identify and separate species are examined, along with recent changes in the genus's classification and newly added species. Cytogenetic studies, such as chromosome number, karyotype analysis, and genome size differences, are presented to illustrate how they aid in understanding the relationships among species. The use of other tools, including DNA markers and phylogenetic analyses, is also described, particularly in addressing taxonomic problems where morphology alone is insufficient. Recent advances in genomic techniques are also discussed, as they provide more detailed information about genetic diversity and support more accurate taxonomic decisions. Overall, this review brings together information from morphology, cytogenetics, molecular biology, and genomics to provide an up-to-date overview of the genus Onobrychis. The aim is to provide a clear and useful overview for researchers studying this group and those interested in its agricultural and economic value.