Transcriptome derived microsatellite markers in Valeriana clarionifolia reveal transferability among Patagonian Valeriana species

Abstract

Several species within the genus Valeriana are globally recognized for their medicinal properties. However, their increasing economic value has led to overharvesting of natural populations, posing a serious threat to their long-term sustainability. Effective strategies for conservation and rational use require accurate species identification and robust assessment of genetic diversity, yet molecular tools for these purposes remain scarce in genus Valeriana. In this study, we developed microsatellite markers based on transcriptomic data from Valeriana clarionifolia. A total of 2216 putative simple sequence repeat (SSR) loci were identified from a transcriptome deposited in the NCBI Sequence Read Archive (BioProject PRJNA950387), and primers were designed for 691 candidate markers. From 60 selected loci, twelve polymorphic SSR markers were isolated and evaluated in V. carnosa Sm., V. clarionifolia Phil., V. gaimanensis N. Nagh., V. moyanoi Speg., and V. philippiana Briq. Mean cross-species transferability and polymorphism were 91.67% and 83.34%, respectively. The number of alleles per locus ranged from four to fourteen, with an average polymorphism information content (PIC) of 0.67. Among the evaluated loci, primer valcla4800 showed the highest discriminatory capacity (PIC=0.89). This study represents the first genomic characterization of native Valeriana species from Patagonia and demonstrates the high transferability and informativeness of transcriptome-derived SSR markers within the genus. The molecular tools generated here provide valuable resources for species identification, genetic diversity assessment, and selection of plant material, supporting conservation efforts and sustainable use of medicinal plants.