Morphological And Population Genomics Features Underlying The Germplasm Resource Characteristics Of Apis Cerana Cerana In East China

The adaptation of organisms to changing environments is self-evident to the importance of populations.Bees can pollinate plants in various environments and climates.They are the best pollinating insects for various crops,vegetables and fruit trees and other flowering plants.They also play an important role in maintaining the ecological balance of the earth.The Apis ceranas is a subspecies of the Oriental honeybee,which is of great significance to China's primitive natural environment,native ecosystem and species diversity.In recent years,due to the continuous increase in China 's population,fragmented and degraded habitat environments have placed tremendous pressure on the health of bees and their ability to withstand winter survival.A comprehensive understanding of bees is of great significance for increasing global food production,detecting the degree of environmental changes,and protecting the ecological balance.On the other hand,the research on the evolutionary biology of Apis ceranas explores their adaptive mechanisms to cope with climate change,thereby providing basic knowledge for the evolution and adaptation of Apis ceranas.In this study,a combination of morphology and genomics was applied to MY,YY,ZZ,WLN,QD,in Shandong province,LA in Anhui province,Qingchuan in Sichuan province,Wulong in Chongqing province,HZ in Shanxi province,and WC in Hainan province.462 Chinese honeybees in 31 populations in 11 regions were tested for 39 representative morphological traits.We extracted 8 Chinese honeybees in each group,and a total of 243 honeybees were subjected to 2b-RAD simplified genome sequencing.By measuring the morphological characteristics of Apis ceranas in Mengyin,Yiyuan,Zaozhuang,Wulian,Sheshan,Lu'an and Central China,Qingchuan,Wulong,Hanzhong and Hainan Island,we compared the data and classified a significant difference was found between most of the morphological indicators of the Apis cerana(P <0.05).An index of the wing vein angle as a fast classification method was proposed.It was divided into 4 ecotypes,Hainan,Central China and East China,of which the Apis cerana in East China was divided into two types.(Yiyuan(YY),Mengyin(MY)and Lu'an(LA)belong to the first category,Lintong(LQ),Zaozhuang(ZZ),and Rizhao(RZ)belong to the second category.Sequencing revealed 11,506 high-quality SNPs,with minor allele frequencies(MAF)>1%.The average number of unique tags in each sample was 49,055,the average depth was72.61 x,and the unique tag comparison rate for all samples was 64.27 % ~ 86.33%.The differential SNPs were obtained by comparing the reference genomes.We used genomics to assess the population structure and genetic diversity.The inbreeding coefficient(Fst)of the Apis cerana in the sampling area was 0.132(0.041-0.257),and the polymorphic information content It is 0.236,which is in a state of moderate genetic differentiation with a genetic distance of 0.46-2.73.It is found that there is a large genetic difference at the level of subspecies,especially in East China.A total of 121 SNPs was screened by the selective evolution analysis,and the number of effective alleles was 1.46.The 117 selected evolutionary gene IDs were obtained.Five groups of candidate genes such as "development process" were provided using high Fst differences and GO annotations,which enriched " Wnt signaling pathway " and three significant KEGG pathways.It was found that historical migration occurred between Apis ceranas in North China and central China.In the plains,human activities have caused greater fragmentation of habitats.The protection of Apis ceranas' diversity should focus on the connectivity of the population.The establishment of habitat corridors Protecting local genetic diversity is important.The influence of climate type on population genetic differentiation is small,and the population differentiation status and altitude are significantly negatively correlated(R2 =-0.5545).The genetic differentiation of bee populations located in low altitude areas has fluctuated;Examination revealed that structural characteristics were not obvious,and physical obstacles rather than distance were the driving factors for the differentiation of this highly migratory species.In summary,this study found that the Apis cerana has a large genetic difference at the subspecies level.By comparing the differences in environmental changes in different regions,we found that the Apis cerana has great potential for climate change,providing research and protection for the Apis cerana.Theoretical basis.