Improving Ramie Fiber: Current Progress and Future Directions in Molecular Breeding

Ramie (Boehmeria nivea) is renowned for its superior fiber strength, length, and unique properties, yet its genetic improvement has lagged behind other fiber crops. This review synthesizes recent advances in ramie fiber development at the genetic, genomic, and molecular levels. Population genomic analyses have uncovered distinct domestication, improvement, and feralization signatures, identifying numerous fiber-related genes under selection. Parallel genetic and molecular studies have mapped scores of loci and genes governing fiber formation, laying the foundation for molecular breeding. However, despite the availability of genetic transformation systems, the need for methodological improvements remains a major challenge for engineering fiber traits via transgenic approaches. Overall, a solid research foundation has been established. Future progress in establishing marker-assisted and genomic selection breeding systems, optimizing transformation protocols, and developing efficient gene-editing methods holds promise for realizing molecular breeding to enhance fiber quality and yield in ramie.