Kholina A.B., Pozdnyakova T.E., Sandanov D.V.
Izvesniya Saint-Petersburg state agrarian university 2022; (3 (68)): 20–31
Oxytropis lanata (Pall.) DC., O. myriophylla (Pall.) DC. and O. oxyphylla (Pall.) DC. species have medicinal properties and are used in Tibetan, Mongolian and Chinese medicine. All of them are characterized by narrow ecological confinement to specific habitats and often form isolated populations, which carries a certain threat of reducing the genetic variability and adaptive potential of the species. The aim of the study was to investigate the genetic diversity of O. lanata, O. myriophylla and O. oxyphylla populations in Baikal Siberia based on nucleotide polymorphism analysis of intergenic spacer psbA-trnH, trnL-trnF, and trnS-trnG chloroplast DNA and formulate practical recommendations for species conservation. In O. lanata, marker nucleotide substitutions were detected, indicating significant divergence in the chloroplast genome of the species. Analysis of the genealogical relationships showed a division of the haplotypes of O. oxyphylla into two phyletic lines. The low values of differentiation and the absence of nucleotide divergence between populations in O. myriophylla indicate that the species is a genetically homogeneous group. Most populations are characterized by a high level of haplotype diversity (0.700 - 1.000), which indicates that they are relatively stable. Only three populations of O. lanata and four populations of O. oxyphylla show possible recent demographic expansion, a spatial expansion with high levels of gene flow between neighboring populations. The low level of nucleotide diversity (0.0003 - 0.0045) in the populations of the three species, the absence of nucleotide substitutions in all populations of O. myriophylla and some populations of O. lanata and O. oxyphylla, and the narrow ecological confinement of these species indicate the need for certain measures to protect all known habitats, search for new species locations, study the demographic structure, viability, genetic diversity of populations and regularly monitor their condition.
