Understanding genome-wide diversity,inbreeding,and the burden of accumulated deleterious mutations in small and isolated populations is essential for predicting and enhancing population persistence and resilience.Howe...Understanding genome-wide diversity,inbreeding,and the burden of accumulated deleterious mutations in small and isolated populations is essential for predicting and enhancing population persistence and resilience.However,these effects are rarely studied in limestone karst plants.Here,we re-sequenced the nuclear genomes of 62 individuals of the Begonia masoniana complex(B.liuyanii,B.longgangensis,B.masoniana and B.variegata)and investigated genomic divergence and genetic load for these four species.Our analyses revealed four distinct clusters corresponding to each species within the complex.Notably,there was only limited admixture between B.liuyanii and B.longgangensis occurring in overlapping geographic regions.All species experienced historical bottlenecks during the Pleistocene,which were likely caused by glacial climate fluctuations.We detected an asymmetric historical gene flow between group pairs within this timeframe,highlighting a distinctive pattern of interspecific divergence attributable to karst geographic isolation.We found that isolated populations of B.masoniana have limited gene flow,the smallest recent population size,the highest inbreeding coefficients,and the greatest accumulation of recessive deleterious mutations.These findings underscore the urgency to prioritize conservation efforts for these isolated population.This study is among the first to disentangle the genetic differentiation and specific demographic history of karst Begonia plants at the whole-genome level,shedding light on the potential risks associated with the accumulation of deleterious mutations over generations of inbreeding.Moreover,our findings may facilitate conservation planning by providing critical baseline genetic data and a better understanding of the historical events that have shaped current population structure of rare and endangered karst plants.展开更多
Evaluating the genetic status of threatened species is an essential task in conservation genetics.However,the genetic status of threatened species has been mostly evaluated through techniques that fail to estimate gen...Evaluating the genetic status of threatened species is an essential task in conservation genetics.However,the genetic status of threatened species has been mostly evaluated through techniques that fail to estimate genetic diversity at the whole genomic level.Next generation sequencing can meet this demand,but high quality samples such as blood or muscle tissues are required.However,it is difficult to collect such samples from threatened species because sampling work may impact their health.Therefore,it is essential to design a workflow to evaluate the whole genomic status of threatened species using non-destructive sampling.Even though non-destructive sampling has been used in traditional barcoding technique,the barcoding technique cannot evaluate the whole genomic status.Brown Eared Pheasant(Crossoptilon mantchuricum)is an endangered species,with captive populations maintained in Taiyuan Zoo,China,and Europe.However,the genetic diversity,inbreeding pattern,and mutation load of these two populations are unclear.To uncover the genetic status of these two captive populations,we applied 2b-RAD technology to evaluate the genomic status of these populations using feathers as samples.The feathers could be collected by non-destructive sampling.The results indicate that the Taiyuan Zoo population has a lower genetic diversity and higher inbreeding coefficient than the European population.The Taiyuan Zoo population has lethal mutations when homozygous.The current project uses a non-destructive sampling technique to evaluate the whole genomic status of the two captive populations,providing a paradigm for conservation genetics,which will facilitate the development of conservation biology.展开更多
基金supported by Key-Area Research and Development Program of Guangdong Province(Grant No.2022B1111230001)National Natural Science Foundation of China(31860048).
文摘Understanding genome-wide diversity,inbreeding,and the burden of accumulated deleterious mutations in small and isolated populations is essential for predicting and enhancing population persistence and resilience.However,these effects are rarely studied in limestone karst plants.Here,we re-sequenced the nuclear genomes of 62 individuals of the Begonia masoniana complex(B.liuyanii,B.longgangensis,B.masoniana and B.variegata)and investigated genomic divergence and genetic load for these four species.Our analyses revealed four distinct clusters corresponding to each species within the complex.Notably,there was only limited admixture between B.liuyanii and B.longgangensis occurring in overlapping geographic regions.All species experienced historical bottlenecks during the Pleistocene,which were likely caused by glacial climate fluctuations.We detected an asymmetric historical gene flow between group pairs within this timeframe,highlighting a distinctive pattern of interspecific divergence attributable to karst geographic isolation.We found that isolated populations of B.masoniana have limited gene flow,the smallest recent population size,the highest inbreeding coefficients,and the greatest accumulation of recessive deleterious mutations.These findings underscore the urgency to prioritize conservation efforts for these isolated population.This study is among the first to disentangle the genetic differentiation and specific demographic history of karst Begonia plants at the whole-genome level,shedding light on the potential risks associated with the accumulation of deleterious mutations over generations of inbreeding.Moreover,our findings may facilitate conservation planning by providing critical baseline genetic data and a better understanding of the historical events that have shaped current population structure of rare and endangered karst plants.
基金funded by the National Natural Science Foundation of China(Grant No.31872244 to Z.Z.)Priority Academic Program Development of Jiangsu Higher Education Institutions,Beijing Zoo Management Office(No.zx2019016 to J.Z.)the Biodiversity Survey,Monitoring and Assessment Project(2019-2023)of the Ministry of Ecology and Environment,China(No.2019HB2096001006 to Z.Z.)。
文摘Evaluating the genetic status of threatened species is an essential task in conservation genetics.However,the genetic status of threatened species has been mostly evaluated through techniques that fail to estimate genetic diversity at the whole genomic level.Next generation sequencing can meet this demand,but high quality samples such as blood or muscle tissues are required.However,it is difficult to collect such samples from threatened species because sampling work may impact their health.Therefore,it is essential to design a workflow to evaluate the whole genomic status of threatened species using non-destructive sampling.Even though non-destructive sampling has been used in traditional barcoding technique,the barcoding technique cannot evaluate the whole genomic status.Brown Eared Pheasant(Crossoptilon mantchuricum)is an endangered species,with captive populations maintained in Taiyuan Zoo,China,and Europe.However,the genetic diversity,inbreeding pattern,and mutation load of these two populations are unclear.To uncover the genetic status of these two captive populations,we applied 2b-RAD technology to evaluate the genomic status of these populations using feathers as samples.The feathers could be collected by non-destructive sampling.The results indicate that the Taiyuan Zoo population has a lower genetic diversity and higher inbreeding coefficient than the European population.The Taiyuan Zoo population has lethal mutations when homozygous.The current project uses a non-destructive sampling technique to evaluate the whole genomic status of the two captive populations,providing a paradigm for conservation genetics,which will facilitate the development of conservation biology.
