KHOLINA ALLA B., ARTYUKOVA ELENA V., SANDANOV DENIS V., SAMDAN ANDREY M.
Biota and environment of natural areas 2026; 14(3): 6-22
For the first time, data on the genetic diversity, population structure, demographic dynamics, and phylogenetic relationships of a rare species, Manchurian-Daurian endemic, medicinal plant Oxytropis komarovii Vass. (Fabaceae) were obtained based on the analysis of nucleotide sequence polymorphism of the intergenic psbA-trnH, trnL-trnF, and trnS-trnG of chloroplast DNA. All O. komarovii populations were characterized by a high level of haplotype diversity (0.644-0.810) and a low level of nucleotide diversity (0.0010-0.0020). Molecular dispersion analysis showed a moderate and statistically significant level of population di erentiation: about 21% of all genetic variability is accounted for by the interpopulation component (ΦST = 0.210, P < 0.05). The presence of unique haplotypes in each population, the absence of shared haplotypes, and the level of population di erentiation all indicate the need to apply conservation measures to all populations studied in this work. Reconstruction of the demographic histories of O. komarovii revealed that populations have a unimodal mismatch distribution of pairwise nucleotide di erences, consistent with a model of demographic expansion and/or spatial expansion in the past. Reconstruction of phylogenetic and genealogical relationships revealed that the haplotypes of O. komarovii and the closely related species O. hirta form a single group/ branch, consistent with their taxonomic a liation within the section Brachytropis of the subgenus Triticaria. Molecular di erences were identified between O. borissovae and O. aciphylla of the section Lycotriche of the subgenus Tragacanthoxytropis, indicating significant divergence of their chloroplast genomes and the distinct species status of O. borissovae.
