基于微卫星标记的东北黑蜂群体遗传多态性分析

 【目的】探讨东北黑蜂（Apis mellifera ssp.）国家级自然保护区内的蜜蜂群体遗传多态性情况。 【方法】采用16个微卫星位点对来自中国黑龙江省饶河县7个不同区域的东北黑蜂样本进行遗传多样性检测。【结果】245只东北黑蜂个体在16个微卫星座位上共发现725个等位基因；除A028、A024和A088外，其余的13个微卫星座位均表现出高度多态性；东北黑蜂7组样本的平均多态信息含量（PIC）为0.60±0.05，平均观察杂合度（Ho）为0.62±0.21，平均期望杂合度（He）为0.65±0.19；除第2组样本外，其它样本的近交系数（Fis）均为正值，表明这些样本内存在不同程度的近交现象；7组样本间的分化系数（Fst）为0.03―0.14，遗传距离（DA）为0.08―0.35；群体的总基因流（Nm）为1.59，总分化系数（Fst）为0.14。聚类分析结果表明东北黑蜂具有2个不同的进化分支。【结论】东北黑蜂群体朝着2个不同的方向进化；总体遗传多态性程度较高；由于群体间的基因交流程度比较频繁，因此目前仅产生了中等程度的遗传分化。本研究结果对东北黑蜂的选育和保护具有重要的指导意义。

Genetic Diversity of Northeastern Black Bee (Apis mellifera ssp.) in China Based on Microsatellite Markers

【Objective】 The objective of the study is to discuss the genetic diversity of the northeastern black bee (Apis mellifera ssp., also named Raohe black bee) from China National Nature Reserve for the Black Bee (CNNRBB). 【Method】The genetic diversity of northeastern black bee from 7 districts in Raohe County, Heilongjiang Province were surveyed by using 16 microsatellite markers. 【Result】A total of 725 alleles were detected at 16 loci among 245 workers, all loci except A028, A024 and A088 showed high polymorphism in the populations studied, the average polymorphism information content (PIC) was 0.60±0.05, the mean observed heterozygote (Ho) was 0.62±0.21, and the expected heterozygote (He) was 0.65±0.19, positive values of the inbreeding coefficient (Fis) were found (excluding two populations), indicating a certain level of inbreeding. Coefficients of genetic differentiation (Fst) between populations ranged from 0.03 to 0.14, and the Nei's genetic distance (DA) was from 0.08 to 0.35, moderate genetic differentiation (Fst =0.14) and a high estimate of gene flow (Nm=1.59) were detected in the total populations. The clustering analysis indicated that there were two evolutionary branches in the northeastern black bees.【Conclusion】Northeastern black bee has two evolutionary directions, the genetic diversity was high, and because of the high rate of gene flow, the genetic differentiation was moderate among populations. These results could help selective breeding programs, conservation planners design and locate reserves more likely to resist invasion.