Objective To identify the morphological and molecular characterization of mite Tyrophagus putrescentiae. Methods T. putrescentiae mites were collected from the flour stored over 1 year and the life cycle was maintained in the lab. The larval, nymph and adult mites and the eggs were observed under optical microscope and scanning electron microscope (SEM). The DNA was extracted from the mites, the cytochrome oxidase subunit Ⅰ(cox1) and internal transcribed spacer(ITS) genes were amplified by PCR. The PCR products were ligated into the vector pMD19-T, then transformed into Escherichia coli. The inserts in the positive clones were DNA sequenced. The obtained DNA sequences were analyzed by DNAStar software and performed BLAST alignment analysis against mite sequences in GenBank. The phylogenetic tree was constructed accordingly. Results The body of T. putrescentiae was oval shaped with a smooth, colorless and translucent surface. The pincers and feet were brownish, and the setae on the body were slender but not stiff. Morphological structures of T. putrescentiae, including legs, setae, external genitalia and accessories, could be clearly identified under SEM. The larva had three pairs of legs, the nymph and adult had four pairs of legs and one pair of chela. The body was composed of three segments. Within Ⅳ coxa, the reproductive organ can be discovered, the lateral plates bended outward to form a "herringbone" shape, and the anus was slender and located in the posterior half with longer anal hair beyond the body. The hair d1 is short, the d2 is longer, and hair hi is longer than the hair he. The clearly discovered hair pa in the posterior is beyond the body. The hair vi and outer hair ve were found in the forefoot, the hair sci was longer than that of the sce, and the outer hair o1 of the knee was slightly longer than that of o2. The PCR products of ITS amplified from T. putrescentiae was 1 852 bp and cox1 was 469 bp in length. BLAST search confirmed that cox1 sequence matched the sequence of T. putrescentiae. The A+T content of cox1 sequence was 65.7%. The phylogenetic tree based on cox1 gene sequence showed that the T. putrescentiae is genetically close to T. longier with sequence similarity of 91.5%. The A+T content of ITS sequences was 53.6%. The phylogenetic tree based on ITS showed that the sequence of ITS of T. putrescentiae was quite different from that of other Acarida, with the sequence similarity of 37.7%-41.8%. Conclusion The mites collected from the stale flour were identified as T. putrescentiae based on their morphological characterization and amplified cox1 and ITS gene sequences.
[1] Yu X, Fan QH.Occurrence and control of Tyrophagus putrescentiae[J]. Fujian Agricrltural Sci Technol, 2002(6): 49-50. (in Chinese)
(于晓, 范青海. 腐食酪螨的发生与防治[J]. 福建农业科技, 2002(6): 49-50.)
[2] Hong Y, Chai Q, Tao N, et al. A case of dermatitis caused by Tyrophagus putrescentiae[J]. Chin J Schisto Control, 2017, 29(3): 395-396. (in Chinese)
(洪勇, 柴强, 陶宁, 等. 腐食酪螨致皮炎1例[J]. 中国血吸虫病防治杂志, 2017, 29(3): 395-396.)
[3] Yi ZQ, Yang L, Xia W, et al. Research on allergens of Tyrophagus putrescentiae[J]. J Pathog Biol, 2017, 12(9): 923-926. (in Chinese)
(易忠权, 杨李, 夏伟, 等. 腐食酪螨过敏原研究进展[J]. 中国病原生物学杂志, 2017, 12(9): 923-926.)
[4] Yang L.Research progress on human diseases caused by mites[J]. China Heal Care Nutr, 2016, 26(31): 4. (in Chinese)
(杨琳. 螨虫引起人类疾病的相关研究进展[J]. 中国保健营养, 2016, 26(31): 4.)
[5] Li CP, Shen ZP.Introduction to Chinese Acaroid mites[M]. Beijing: Science Press, 2016: 477-483. (in Chinese)
(李朝品, 沈兆鹏. 中国粉螨概论[M]. 北京: 科学出版社, 2016: 477-483.)
[6] Wen SY, He XF.A method of rapid preparation of trace-DNA templates of insects for PCR[J]. Entomol Knowl, 2003, 40(3): 276-279. (in Chinese)
(温硕洋, 何晓芳. 一种适用于昆虫痕量DNA模板制备的方法[J]. 昆虫知识, 2003, 40(3): 276-279.)
[7] Sun ET, Li CP, Nie LW, et al. The complete mitochondrial genome of the brown leg mite, Aleuroglyphus ovatus (Acari ∶ Sarcoptiformes): evaluation of largest non-coding region and unique tRNAs[J]. Exp Appl Acarol, 2014, 64(2): 141-157.
[8] Yu LL, Zhang CB, Teng FX, et al. Meta-analysis on the distribution of domestic mites in China[J]. J Pathog Biol, 2017, 12(5): 423-427, 433. (in Chinese)
(俞黎黎, 张承伯, 滕飞翔, 等. 我国尘螨分布的Meta分析[J]. 中国病原生物学杂志, 2017, 12(5): 423-427, 433.)
[9] Guo W, Jiang YX.Morphological observation on adult Tyrophagus putrescentiae[J]. J Biol, 2014, 31(3): 95-98. (in Chinese)
(郭伟, 姜玉新. 腐食酪螨成螨形态观察[J]. 生物学杂志, 2014, 31(3): 95-98.)
[10] Yang L, Ma GF, Li QS, et al. Use of a multimedia diagnostic microscope to morphologically identify adult Tyrophagus putrescentiae[J]. J Pathog Biol, 2018, 13(2): 164-167. (in Chinese)
(杨李, 马桂芳, 李启松, 等. 超高倍多媒体显微诊断仪在腐食酪螨成螨形态鉴定中的应用[J]. 中国病原生物学杂志, 2018, 13(2): 164-167.)
[11] Shi YL, Wan XL, Jiang ZH, et al. Scanning electron microscopic and transmission electron microscopic observations of the tegument structure of adult Clonorchis sinensis[J]. Chin J Parasitol Parasit Dis, 2018, 36(2): 184-186. (in Chinese)
(石云良, 万孝玲, 蒋智华, 等. 华支睾吸虫成虫体被结构扫描电镜和透射电镜观察[J]. 中国寄生虫学与寄生虫病杂志, 2018, 36(2): 184-186.)
[12] Yang XQ.The phylogeographic structure of Cheyletus malaccensis (Acari ∶ Cheyletidae) in southeastern China based on mitochondrial COI sequence data[D]. Nanchang: Nanchang University, 2013.
(杨小强. 基于线粒体COI序列的中国东南地区马六甲肉食螨的系统地理结构研究[D]. 南昌: 南昌大学, 2013.)
[13] Yang SY, Zhou XL, Song LW, et al. Analysis of genetic differentiation among different geographic populations of Tetranychus truncates (Acari ∶ Tetranychidae) in Gansu Province, northwestern China based on mtDNA COI gene[J]. Acta Entomol Sin, 2017, 60(9): 1083-1092. (in Chinese)
(杨顺义, 周兴隆, 宋丽雯, 等. 基于mtDNA COI基因的甘肃截形叶螨不同地理种群遗传分化分析[J]. 昆虫学报, 2017, 60(9): 1083-1092.)
[14] Ben-David T, Melamed S, Gerson U, et al. ITS2 sequences as barcodes for identifying and analyzing spider mites (Acari ∶ Tetranychidae)[J]. Exp Appl Acarol, 2007, 41(3): 169-181.
[15] Zou ZW, Chen F, Xia B, et al. Sequence analysis of ITS gene in several Amblyseiinae (Acari ∶ Phytoseiidae)[J]. Sci Agric Sin, 2011, 44(23): 4945-4951. (in Chinese)
(邹志文, 陈芬, 夏斌, 等. 几种钝绥螨ITS基因片段的序列分析[J]. 中国农业科学, 2011, 44(23): 4945-4951.)
[16] Wu HB, Cheng J, Wen CG, et al. Analysis gene sequences of ribosomal ITS2 and phylogeny from five unionicolid mites species[J]. J Nanchang Univ Nat Sci, 2011, 35(2): 178-183. (in Chinese)
(吴浩彬, 程剑, 文春根, 等. 5种蚌螨ITS2基因片段序列及其系统发育分析[J]. 南昌大学学报(理科版), 2011, 35(2): 178-183.)
