Genetic diversity of the critically endangered Ferula sinkiangensis KMShen (Apiaceae) and the implications for conservation

Research on the genetic diversity and structures of endangered plant species with small population sizes is a prerequisite for developing reasonable conservation strategies. Ferula sinkiangensis K.M.Shen is a critically endangered herbaceous perennial and monocarpic medical plant growing in semiarid steppe ecosystems with a small population size within the Yili Valley in Xinjiang, China. Unfortunately, the lack of genetic information has limited our ability to initiate effective conservation strategies for the species. In this study, 14 polymorphic microsatellite primers of E sinkiangensis were developed and characterized using Illumina HiSeq paired-end reads from genomic DNA. Primers were used to assess the genetic diversity and structure of the species in the Yili Valley. A total of 92 alleles were detected across 14 microsatellite loci from 65 specimens of sinkiangensis. Moderate to high levels of genetic diversity (He = 0.446,I= 0.821, PPB = 92.86%) were found within the species. Our results contradict the general hypothesis that rare and endangered species with small population sizes and narrow ranges of distribution exhibit low levels of genetic diversity. The moderate to high levels of genetic diversity within the species can be explained by the mating system, life history traits, and human activities in recent years. Several reasonable conservation and reintroduction strategies are proposed, including maintenance of the plant's natural habitats, seeds or seedlings collection for germplasm storage, and artificial breeding of the species.