Genetic diversity and population structure of Chinese honeybees (Apis cerana) under microsatellite markers
Using 21 microsatellite markers and PCR method, the polymorphisms of 20 Apis cerana honeybee populations across China was investigated and the genetic structure and diversity of the populations were explored. The results showed that 507 alleles (mean 24.14 per locus, ranging from 13 to 45) were observed in 842 honeybees. Wuding bee had the highest level of heterozygosity (0.695), and the lowest estimate was 0.207 for Changbai bee. The global heterozygote deficit across all populations (Fit) amounted to 0.776. About 42.3% of the total genetic variability originated from differences between breeds, with all loci contributing significantly to the differentiation. An unrooted consensus tree using the Neighbour-Joining method and pair-wise distances showed that 6 populations from Eastern China clustered together. The structure analysis indicated that the 6 populations were separated first. These findings demonstrated that the 6 honeybee populations had close genetic relationships.
Key words: Apis cerana, microsatellite, polymorphism, genetic structure.