Assessing Genetic Diversity in Critically EndangeredChieniodendron hainanensePopulations within Fragmented Habitats in Hainan

Abstract

AbstractHabitat fragmentation engenders a reduction in the geographic distribution of species, thereby rendering diminutive populations susceptible to extinction due to environmental, demographic, and genetic factors.Chieniodendron hainanense(henceforthC. hainanense) exemplifies a wild plant with extremely small populations (WPESP) and faces endangerment, necessitating urgent national conservation efforts. Elucidating the genetic diversity ofC. hainanenseis crucial for uncovering underlying mechanisms and devising protective strategies. In the present study, 35 specimens from six distinct cohort groups were genotyped utilizing genotyping-by-sequencing (GBS) and single nucleotide polymorphism (SNP) methodologies. The results indicated thatC. hainanenseexhibits limited genetic diversity. Observed heterozygosity withinC. hainanensepopulations spanned from 10.79% to 14.55%, with an average value of 13.15%. The sixC. hainanensepopulations can be categorized into two distinct groups: (1) Diaoluoshan and Baishaling, and (2) Wuzhishan, Huishan, Bawangling, and Jianfengling. The degree of genetic differentiation amongC. hainanensepopulations is relatively weak. The observed loss of diversity can be attributed to the effects of natural selection.