From "Omics" to Field: Deciphering the Stress Adaptation Networks and Breeding Potential of Medicago ruthenica L.

Medicago ruthenica L., a superior forage crop within the genus Medicago (Fabaceae), is endowed with remarkable stress tolerance and an abundance of bioactive compounds, conferring significant ecological and forage value. Existing reviews primarily focus on a single research direction, and the most recent findings are dated, failing to cover breakthroughs at the molecular level. This paper systematically synthesizes the latest research progress in five key areas: genetic diversity and genomic studies, biotic stress responses, abiotic stress tolerance mechanisms (drought, salinity, and low temperature, etc.), utilization (including genetic breeding, ecological restoration, and forage development), and future research prospects. This review addresses critical gaps in existing literature, particularly regarding advances in genomic sequencing, biotic stresses, and research on stress-associated microorganisms. Research indicates that M. ruthenica exhibits extensive genetic diversity, and its genome contains numerous positive selection signals associated with stress resistance. It can tolerate multiple abiotic and biotic stresses through morphoplasticity, physiological metabolic regulation, and transcriptional regulation. Furthermore, its symbiosis with microorganisms such as rhizobia significantly enhances its stress tolerance. M. ruthenica demonstrates outstanding application potential in degraded grassland restoration and high-quality forage production. Future research should focus on mining stress-resistant genes, optimizing molecular breeding techniques, and integrating artificial intelligence into breeding practices. That will facilitate its transformation from a regional endemic resource to a commercially viable functional species, thereby providing robust support for ecological security and the sustainable development of grassland-based livestock husbandry in cold and arid regions.