Biodiv Sci ›› 2022, Vol. 30 ›› Issue (7): 21508.  DOI: 10.17520/biods.2021508

• Original Papers: Genetic Diversity • Previous Articles     Next Articles

Conservation genomics analysis revealed the endangered mechanism of Adiantum nelumboides

Weiyue Sun1,2, Jiangping Shu2,3, Yufeng Gu1,4, Morigengaowa4, Xiajin Du2, Baodong Liu1,*(), Yuehong Yan2,*()   

  1. 1. Key Laboratory of Plant Biology, College of Heilongjiang Province, Harbin Normal University, Harbin 150025
    2. The Orchid Conservation and Research Centre of Shenzhen, Shenzhen, Guangdong 518114
    3. South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650
    4. Shanghai Chenshan Plant Science Research Center, Chinese Academy of Sciences, Shanghai 201602
  • Received:2021-12-09 Accepted:2022-04-09 Online:2022-07-20 Published:2022-06-21
  • Contact: Baodong Liu,Yuehong Yan


Aims: Understanding the mechanism that leads species to endangerment is crucial to the conservation of biodiversity. Adiantum nelumboides is a key wild plant that is protected at the national level, and its genetic diversity and endangerment mechanism are controversial.
Methods: A total of 28 A. nelumboides samples, from six populations, were used to obtain single-nucleotide variation sites (SNP) by the genotyping by sequencing (GBS) method. The genetic diversity and structure of the population were analyzed and combined with the change in the potential distribution area of species under different climate scenarios. Then the possible causes of endangerment and scientific protection strategies of A. nelumboides were discussed.
Results: The results showed that 29.6 Gb of data was obtained based on the GBS sequencing, and 9,423 high-quality SNP loci were screened. Adiantum nelumboides had low genetic diversity (Ho = 0.138, He = 0.232, Pi = 0.373), low genetic differentiation (Fst = 0.0202) and gene flow (Nm = 1.9613). The A. nelumboides samples are from two ancestral haplotypes, their genome size was 5.01‒5.83 Gb, they were tetraploid, and the GC content was about 39%‒41%. Under future climate change, the potential distribution area of A. nelumboides will increase slightly, in which the area of high fitness is lost. The primary areas that are suitable for the plant are distributed in Wanzhou, Chongqing and further north. The dominant factors affecting its distribution are monthly mean differences in diurnal temperatures and precipitation during the coldest season.
Conclusions: Due to the low genetic diversity, lack of gene exchange between different populations, and changes in climatic conditions, suitable growth areas for A. nelumboides become narrow, resulting in a sharp decline in species diversity and population size. Therefore, their low regeneration ability and excessive disturbance from human activities might be the main reasons for the endangered status of A. nelumboides. It was recommended to strengthen in situ conservation of A. nelumboides. Measures such as habitat restoration and natural regression must be discussed to increase gene exchange across populations. At the same time, a core germplasm of this species must be constructed to prevent the aggravation of genetic resource loss.

Key words: genetic structure, species distribution models, dominant climate factor, genetic diversity, genotyping- by-sequencing