%A Weiyue Sun, Jiangping Shu, Yufeng Gu, Morigengaowa, Xiajin Du, Baodong Liu, Yuehong Yan %T Conservation genomics analysis revealed the endangered mechanism of Adiantum nelumboides %0 Journal Article %D 2022 %J Biodiv Sci %R 10.17520/biods.2021508 %P 21508- %V 30 %N 7 %U {https://www.biodiversity-science.net/CN/abstract/article_82499.shtml} %8 2022-07-20 %X

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.