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目的 以核糖体第二核糖体内部转录间隔区 (ITS2) 作为分子标记, 对粉尘螨、屋尘螨、腐食酪螨和热带无爪螨进行系统发育树分析.方法 PCR扩增种常见储藏物螨种的ITS2基因并测序, 进行序列比对分析;从GenBank下载8条螨虫的ITS2序列, 用MEGA 2.1软件构建分子系统树, 进行系统进化分析.结果 分析4种螨的ITS2序列长度为316～487bp, 种内基因遗传距离为0.003 823～0.052 599, 种间遗传距离为0.187 440～0.534 699.以长食酪螨 (Tyrophagus longior) 为外类群构建系统发育树, 进行系统发育分析, 屋尘螨与粉尘螨亲缘关系较近, 腐食酪螨及热带无爪螨分别位于发育树的基部和中部, 系统发育树结果与根据形态分类对应.结论 依据ITS2基因片段序列及系统发育树可对常见螨种鉴定, ITS2基因片段可作为螨种鉴定的分子标记.“,”Objective To use the ribosomal second internal transcribed spacer (ITS2) as a molecular marker in order to analyze the phylogenetic tree of 4 common storage mites (Dermatophagoides farinae, Dermatophagoides pteronyssinus, Tyrophagus putrescentiae, and Blomia tropicalis). Methods The ITS2 regions of 4 species of common storage mites were obtained using apolymerase chain reaction and sequenced.Eight sequences of mite ITS2 were retrieved from GenBank.Phylogenetic relationships were analyzed using MEGA 6.0. Results The lengths of ITS2 sequences varied from 316 to 487 bp and the intraspecific genetic distance was in the range of 0.003 823-0.052 599, whereas the interspecific genetic distance was 0.187 440-0.534 699.Using the sequences of Tyrophagus longior as an out-group, aphylogenetic tree was constructed.According to this tree, D.farinae was clustered with D.pteronyssinus, Tyrophagus putrescentiae was located at the base of the tree, and Blomia tropicalis was located in the trunk.The phylogeny relationships were identical to relationships based on morphological classification. Conclusion The ITS2 regions can be used as a DNA marker to identify different species of astigmatid mites.