中文摘要：

为研究安徽江淮水牛群体的分子种质特性,本试验测定了江淮水牛2个亚群共82个个体的线粒体D-loop区和细胞色素b基因完整序列,分析了序列遗传多态性及系统进化关系,并结合GenBank中已发表的141条中国水牛D-loop序列,进行了联合分析。结果在D-loop区内共发现核苷酸多态位点91个,组成104个单倍型,其中32个是在江淮水牛中新发现的单倍型。总体mtDNA D-loop区核苷酸多样性为（0.015 43±0.001 42）,单倍型多样性为（0.948±0.009）。其中,江淮水牛的mtDNA D-loop区核苷酸多样性为（0.014 89±0.002 32）,单倍型多样性为（0.955±0.013）,表明其群体遗传多样性丰富,群体变异性水平与中国其他水牛群体接近。根据线粒体D-loop区单倍型构建系统树和进化网络,显示江淮水牛存在沼泽型水牛线粒体支系A和B,表明其具有2个线粒体母系来源,其中B支又分为b1和b2两个亚支;针对细胞色素b基因的进化分析也支持这一结论。这些研究结果为今后开展江淮水牛遗传资源的保护和利用提供了客观依据。

英文摘要：

To study the molecular germplasm characteristics of Jianghuai buffalo,the genetic diversity and phylogeny of mitochondrial DNA D-loop region and the complete sequence of cytochrome（Cyt b） gene of 82 Jianghuai buffaloes sampled from two subpopulations were investigated.These data were analyzed together with the published D-loop sequences of 141 Chinese buffaloes in GenBank.A total of 104 haplotypes and 91 nucleotide polymorphic sites were identified.Thirty-two D-loop haplotypes were newly found only in Jianghui buffalo.The estimated overall nucleotide diversity and haplotype diversity were（0.015 43±0.001 42） and（0.948±0.009）,respectively.The genetic variability of Jianghuai buffalo was similar with those of other Chinese buffalo populations,with nucleotide diversity to be（0.014 89±0.002 32） and haplotype diversity to be（0.955±0.013）,which indicated the rich mitochondrial genetic diversity in this population.Phylogenetic tree and network analysis revealed two mtDNA lineages,the A and B lines of swamp buffaloes,and the B line could be further divided into sub-lineages of b1 and b2,which indicated that at least there were two maternal swamp buffalo origins in Jianghuai swamp buffalo population.The results based on the phylogenetic analysis of Cytb gene also supported this conclusion observaed in the D-loop region of Jianghuai buffalo.These findings lay a foundation for conservation and utilization of Jianghuai buffalo genetic resources in the future.