| Genetic diversity and phylogenetic relationship among 180 individuals of 6 Apis cerena populations from Tenchong, Wuliangshan, Diqing, Wuding, Lushui, Xishuangbanna in Yunnan province were evaluated with 21 microsatellite loci. The part of mtDNA tRNAleu-COII of these 6 populations were sequenced and analyzed. Genetic variability within populations and genetic differentiation among populations were estimated, the phylogenetic relationship among the 6 populations were analyzed. The main results were summarized as follows:1. The genetic variability within populations and genetic differentiation among populations were estimated, a total of 207 alleles were detected in 6 populations with 21 microsatellite markers, and the average number of observed alleles was 9.8571±3.9152. The overall expected heterozygosity of all populations and PIC of all loci were 0.7382 and 0.7036, respectively. All 21 microsatellite loci in this study showed high levels of polymorphism. The number of populations deviated from Hardy-Weinberg equilibrium per locus ranged from 3 to 6. In the whole population, the average of genetic differentiation among populations, measured as Fst value, was 26.4% (P <0.001), and 18 loci were contributed significantly (P <0.001) to this differentiation. Significant genetic differentiation was observed among 6 populations, and the deficit of heterozygote was observed very high (0.692) (P <0.001). Reynolds' distance values varied between 0.057 (Wuliangshan-Tengchong pair) and 0.683 (Xishuangbanna–Diqing pair). The Nm value was ranged from 4.255 (between Wuliangshan and Tengchong) to 0.430 (between Xishuangbanna and Diqing).2. The phylogenetic relationship among 6 Apis cerena populations were analyzed, an un-rooted consensus tree was constructed using the Neighbour-Joining method. The tree topology revealed that: Tenchong, and Wuliangshan formed one cluster, and fell together with Diqing, Lushui, Xishuangbannaand Wuding in order.3. The geographical elements may own to the close relationship for particular population pairs, however, the equation Fst/(1-Fst) =–0.1435 + 0.0867ln (d) and the result from Mantel's test (P=0.293) did not provide enough support for a significant correlation between the genetic and geographical pair wise distances. There was no significant correlation between the genetic diversity of mtDNA and the distributing of these populations. The results concluded that the geographical distributing maybe not the determinant influence on the genetic structure of Apis cerena populations in Yunnan during the course of their developed history.4. Part of mtDNA tRNAleu-COII among 60 individuals of 6 Apis cerena populations were sequenced and analyzed. The result showed that the length of tRNAleu-COII concluding a noncoding area and part of sequence of COII in this study was about 480 bp.The noncoding area was 97-98 bp, 8 haplotypes were found,among which, 4 haplotypes were shared among some populations, and the other 4 haplotypes were unique for one population. The distribution of all haplotypes among the populations was disequilibrium and the diversity of haplotypes was ranged from 0.378 to 0.698.The average diversity of haplotypes was 0.752±0.030. Inter-population Nucleotide Divergence (Dxy) in 6 populations was ranged from 0.181%～1.959%, wheras Inter-population Net Nucleotide Divergence (Da) in 6 populations was ranged from -0.005%～0.848%. Kimura 2-parameter distance among these populations ranged from 0.0052～0.0200. Analysis of molecular variance showed that 23.83% of genetic variation was present within populations. Fst value was 0.31723, which indicated the genetic variation was significant within populations (P < 0.001).The 1-259 bp sequence of COⅡwas used to analyzed, 7 haplotypes were found,among which, 5 haplotypes were shared among some populations, and the other 2 haplotypes were unique for one population. The distribution of all haplotypes among the populations was disequilibrium and the diversity of haplotypes was ranged from 0 to 0.644.The average diversity of haplotypes was 0.622±0.055. Inter-population Nucleotide Divergence (Dxy) in 6 populations ranged from 0.077%～0.737%, wheras Inter-population Net Nucleotide Divergence (Da) in 6 populations ranged from -0.021%～0.485%. Kimura 2-parameter distance among these populations ranged from 0.0008～0.0074. Analysis of molecular variance showed that 39.68% of genetic variation was present within populations. Fst value was 0.39688, which indicated the genetic variation was significant within populations (P < 0.001).The results indicated that the genetic diversity of 6 Apis cerena populations was very abundant and there were significant divergence among 6 Apis cerena populations in Yunnan.5. The NJ, ME and UPGMA phylogenetic dendograms of 8 noncoding haplotypes, 7 COⅡhaplotypes in 6 Apis cerena populations and other haplotypes of Apis cerena from GenBank were constructed respectively. The H1, H2, H4 and H8 of noncoding area were placed with haplotypes of Apis cerena from Laos, Vietnam, Japan and Thailand. H7 appeared with Apis cerena from Cambodian, then all of them formed one cluster with haplotypes of Apis cerena in China. All of 7 haplotypes of COⅡfell with haplotypes of Apis cerena in China and Japan. These results indicated that none of the 6 populations in Yunnan province belonged to Apis cerena indica.6. The result from analysis of genetic diversity of 6 Apis cerana populations from Yunnan province inferred from both microsatellite markers and mtDNA gene sequence showed that Wuding population had the highest genetic diversity of 6 populations. NJ, ME and UPGMA dendograms based on Kimura 2-parameter distance of mtDNA sequences in 6 Apis cerena populations showed that, Wuding population was always out of the cluster of the other 5 populations. All results indicated that Wuding population was separate from other 5 Apis cerena populations in Yunnan.
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