Investigation And Comparative Analysis Of Apis Cerana Cerana Genetic Resources In Different Geographical Conditions In China

Ais cerana cerana(abbreviated as A.c.cerana)is an important crop pollinator peculiar to our country,and plays an important role in the healthy development of our country’s agriculture.As a species under national protection of livestock and poultry,the investigation and analysis of its genetic resources are of great significance to the protection and utilization of A.c.cerana germplasm resources and the genetic improvement of A.c.cerana.In this experiment,sampling methods with similar latitudes and different longitudes,similar longitudes and different latitudes,or different altitudes in the same area were used in this experiment.The sampling methods for Mangkang,Shennongjia high-altitude areas,Shennongjia low-altitude areas,Qimen,Jinzhai,Suzhou,Guangzhou,Wenchang etc.The 14 morphological indicators of 378 worker bees in 8 locations were measured,and the latest data on the morphology of A.c.cerana were obtained.At the same time,a total of 80 A.c.cerana samples from these 8 locations were re-sequenced,and the obtained resequencing data were compared with the published resequencing data of 40 A.c.cerana samples from different regions to analyze the current genetics diversity and genetic differentiation of A.c.cerana in my country.Finally,perform genome-wide association analysis on the measured phenotypic data and genome data,and mine candidate genes that control related traits.The main research contents and results are as follows:(1)Through the measurement of 14 morphological indicators of 378 A.c.cerana worker bees in 8 locations including Mangkang,Shennongjia high altitude area,Shennongjia low altitude area,Qimen,Jinzhai,Suzhou,Guangzhou,and Wenchang,the results show that each region have significant differences in different morphological indicators(P<0.05),and the overall trend of morphological indicators from northwest to southeast of China is from large to small.Among them,the measured values of many morphological indicators of A.c.cerana in Mangkang area are the largest,and those in Wenchang area are the smallest.There are significant differences in 11 morphological indicators among populations at different altitudes in the Shennongjia area.Except for the sixth web length,the measured values of other morphological indicators indicate the worker bee populations in the high-altitude area of Shennongjia are higher than those in the low-altitude area.(2)Through re-sequencing the whole genome of A.c.cerana worker bees from 12 locations in my country,and analyzing the population structure of each geographic population,the results show that A.c.cerana species in Mangkang,Wenchang,and Jilin have become an independent type.The A.c.cerana populations in Suzhou,Qimen,Shennongjia,and Jinzhai located in central China are clustered into one type,while the A.c.cerana populations in Guangzhou,Zhangzhou located in south of China and the A.c.cerana populations in Mengyin located in north of China tend to be the same type as the A.c.cerana populations in central China.The A.c.cerana of Qingyuan located in the northeast region is closely related to the A.c.cerana of Jilin but tends to become a separate type.(3)Analysis of the genetic differentiation of A.c.cerana in 12 regions of China.The analysis results show that the average Fst of Jilin is 0.28,the average Fst of Mangkang is 0.16,and the average Fst of Wenchang is 0.19.The three regions are higher genetically differentiated than other regions.(4)Through genome-wide association analysis of the 13 phenotypic trait data obtained by morphological determination and the genome data obtained by resequencing,23 SNP loci significantly associated with 6 phenotypic traits were obtained,among which the SNPs located in LG03 9947860 and LG03 4637007 significantly associated with ML and T3,the SNP located in LG03 8561110 is significantly associated with T3,S3,and T6.Gene annotations and candidate genes are excavated within the range of 50Kb upstream and downstream of the significant SNP,and a total of 6 possible control tables are excavated.According to the 76 candidate genes of type traits,it is finally speculated that LG03_g2379 gene may be a key gene for controlling ML and T3 traits.This study uses morphology and genomics to investigate and compare the genetic resources of A.c.cerana under different geographical conditions in my country,and provides basic data on environmental adaptability of A.c.cerana.This aspect has great significance in genetic breeding and resource protection and utilization in the future for A.c.cerana.