A Study Of The Population Genetics Among Apis Cerana In China

The genetic diversity and population differentiation of Chinese honeybee,Apis cerana,were analyzed across its occurring habitats in this study.A total of 156 sample sites except those from Tibet were analyzed based on the 33 morphological markers,mitochondrial tRNAleu-CO? fragment and 36 microsatellite loci.Based on the honeybee differentiation results,population genetic structure and morphometric characteristics of honeybee were described and paved ways for better conservation,management and utilization of the Apis cerana genetic resources.(1)A total of 317 new tRNAleu?CO? haplotypes and four reported ones were detected from 7910 individual worker bees collected across continental China and adjacent islands(Taiwan and Hainan).The Acmt01001 dominated among them and accounted for 44.62%of worker bees;each of 12 haplotypes accounted for more than 1%and 98 haplotypes were observed only one individual worker bee.(2)The haplotype diversity,average number of nucleotide differences,nucleotide diversity for all the samples ranged 0?0.9,0?2.5,0?0.006,respectively;The observed heterozygosity,expected heterozygosity,mean effective number of alleles,polymorphism information content,Shannon's information index,and allelic richness for all the samples ranged 0.4560?0.2459,0.2418?0.4850,1.4877?3.1786,0.1994?0.4558,0.3881?1.0983,and 1.9414-4.7967,respectively.All the nine parameters were powerful tools for estimating diversity for Chinese honeybee(Apis cerana),based on which most of the honeybee sampling sites show a high or medium level of diversity.To some extent,the honeybee diversity was linked to the honeybee habitation and population size.Small populations and habitat-edge populations showed a low level of diversity;however,large-size population and habitat-center populations showed a high level of diversity.(3)A total of 12 honeybee groups could be clustered and discriminated based on the morphological and molecular data:Changbaishan honeybee,Hainan honeybee,Taiwan honeybee,Southern honeybee,Southern Yunnan honeybee,Sichuan-Yunnan honeybee,Sichuan-Guizhou honeybee,Northwestern honeybee,Northern honeybee,Aba honeybee,Batang honeybee,and Jiulong honeybee.Among these honeybee groups,six honeybee groups,Taiwan honeybee,Sichuan-Yunnan honeybee,Sichuan-Guizhou honeybee,Northwestern honeybee,Batang honeybee,Jiulong honeybee were firstly reported differentiating from the rest of honeybees.Taiwan honeybee showed a furthest distance with continental mainland honeybee probably due to long-term gene flow blocked through the strait.Meanwhile,several honeybee clusters occurred in the Southwest China probably arising from the non-honeybee area block but also the mountainous ranges between valley habituated honeybees.The habitat distribution of Changbaishan honeybee,Aba honeybee,Southern honeybee,and Northern honeybee showed discrepancy with data as previous studies.Changbaishan honeybee was recently refined to Mountain Changbai area in Jilin and Liaoning due to habitat loss.The habitat distributions of Aba honeybee,South honeybee and North honeybee were much more precise than previous data.The habitat of Hainan honeybee and Southern Yunnan honeybee are consistent with preceding studies.