Study On Non-destructive DNA Extraction Method And Molecular Identification Technology In Oribatid Mites

The oribatid mites are of great significance in soil ecological system.They are small(0.1-1mm)and usually sclerotized heavily.In this study,a non-destructive DNA extraction method and molecular identification technology were applied to oribatid mites.In the research of DNA extraction,We provided an efficient and non-destructive DNA extraction method for oribatid mites.By changing the method of DNA extraction and using DNeasy Blood and Tissue kit,a new method for DNA extraction without destroying morphological features can be applied to oribatida mites.Then we used this method to extract DNA of oribatid mites of Galumnidae?Achipteridae and Ceratozetidae.After Comparing these sequence with GenBank database by BLAST software for ensuring the DNA is correct,We found that the morphological characters valuable for identifying the specimens have not been destroyed after DNA extraction and the voucher specimen could be kept for further studies.So,this method can not only obtain high quality DNA templates but also keep voucher specimen.It could be an efficient way to help DNA taxonomy on oribatid mites.In the research of molecular identification in oribatid mites,We chose commonly used 28 S gene and COI gene as molecular markers.Based on 28 S gene,we analyzed the sequence difference of oribatid mites(Galumnidae?Achipteridae?Ceratozetidae and Trhypochthoniidae).By using Ischyropsalis strandi(the GenBank accession number is KP224374.1)as a outgroup,We calculated the genetic distance and constructed the molecular system tree with NJ?ME and UPGMA method.After that,We compared the variation of 28 S gene and COI gene in oribatid mites of Galumnidae.The result of these research showed that: two species of Galumnidae grouped in a single cluster with a 99%?99% and 100% bootstrap support in NJ?ME and UPGMA tree.The species of Ceratozetide and Achipterioidea grouped in a single cluster with 98% bootstrap support in NJ and ME tree,but they were not grouped together in UPGMA tree.The species of Galumnidae ? Ceratozetoidea and Achipterioidea all were not cluster with Trhypochthoniidae,which indicated the 28 S gene of Trhypochthoniidae has a considerable difference with the other three families.And the research in Galumnidae showed that: The variation of COI gene has more than seven times than 28 S gene.So,the COI gene is more suitable for phylogenetic analysis in species and genus level of oribatid mites.