Whole genome resequencing reveals the evolutionary history and geographic isolation of the eastern Asian Hickory (Carya)

Abstract

Societal Impact Statement Unraveling the genetic intricacies and evolutionary history of Asian Hickories through advanced genome sequencing gives valuable insights into their ecological adaptations. Understanding the impact of historical dynamics, climate fluctuations, and geographical barriers on Asian hickories not only contributes to scientific knowledge but also empowers policymakers with evidence‐based decisions and guides conservationists in their efforts to protect vulnerable species. The identification of potential habitats, especially for the endangered Carya kweichowensis, offers a promising avenue for targeted conservation efforts, aligning with global initiatives to preserve Earth's precious biodiversity, but also ensures the conservation of a vital genetic reservoir for nut‐bearing economic tree species. Summary Biogeographic characteristics of disjunct distribution play a vital role in plant geography and the endangered mechanism. The whole genome resequencing provides an opportunity to study the genetic relationship, population diffusion, and floristic evolution of disjunctive‐distribution flora. Based on the SNPs (single nucleotide polymorphisms) data generated by the whole genome deep resequencing of five EA (Eastern Asian) Carya species, we constructed the phylogenetic tree, genetic structure, and species distribution modeling to clarify the phylogenetic relationships and to predict the potential distribution area of EA Carya. Phylogenetic analysis of Carya revealed two distinct clades, separating EA Carya from NA (North America) Carya. C. kweichowensis, an endangered species, showed the lowest nucleotide diversity and the earliest divergence among studied EA Carya species. Species distribution modeling predicted suitable habitats for five EA Carya species, revealing the potential distribution of endangered C. kweichowensis. Importantly, minimal spatial overlap was observed among distribution regions of EA Carya species during different time periods. The uneven regional distribution of EA Carya is believed to be a consequence of Quaternary climate fluctuations, mountain barriers hindering species dispersal, and the limited cold tolerance of these trees. EA Carya highlights the significant role of climate and geological changes in their regional distribution and migration routes in Asia. Furthermore, the discovery of potential habitats offers a promising avenue for the conservation of C. kweichowensis.

Keywords

• Carya
• disjunctive distribution
• endangered
• evolutionary history
• hickory
• resequencing