基于线粒体cytb基因唇䱻3个地理种群的群体遗传多样性分析OA

[Objective]This study aimed to investigate the genetic diversity and population genetic struc-ture of Hemibarbus labeo.[Method]Characterization of genetic variability and population subdivi-sion was performed based on mitochondrial cytochrome b(cytb)sequence data.Analyses of genetic diversity and population structure were conducted based on the mitochondrial cytochrome b(cytb)gene in three populations:the Jialing River(Wusheng County,GA,n=9),the Minjiang River(Leshan section,LS,n=21),and the Yangtze River(Luzhou section,LZ,n=18).[Result]A total of 11 haplotypes were identified from the 48 cytb sequences,with one haplotype shared across all populations.The GA and LS populations exhibited relatively low nucleotide diversity(0.001 72-0.025 09)but high haplotype diversity(0.805-0.833).In contrast,the LZ population exhibited the lowest values for both nucleotide diversity(0.000 10)and haplotype diversity(0.111).The genetic dis-tance was greatest between the GA and LS populations(D=0.026 09),while the genetic dis-tance between LZ and LS was the smallest(D=0.003 60).Analysis of molecular variance(AMOVA)and fixation index(Fst)demonstrate a preponderance of within-population component(64.89%)relative to the among-population fraction(35.11%).A detectable level of genetic dif-ferentiation was observed between GA and LS populations.[Conclusion]The H.labeo population from the mainstream Yangtze River(Luzhou section)demonstrates lower genetic diversity than popula-tions from the Jialing River(Wusheng)and Minjiang River(Leshan)tributaries.These findings high-light the need for targeted conservation efforts to protect the genetic resources of the LZ population.This study provides fundamental data to support the conservation of wild genetic resources in H.labeo.