Abstract:DNAbarcodingisadiagnostictechniqueinwhichshortDNAsequencescanbeusedforspeciesidentification.ThemitochondrialcytochromecoxidasesubunitI()sequenceisusedinDNAbarcodingforspeciesidentificationinmanyorganisms.Inthispaper,thevalidationofthegenesfromsevenspeciesofseacucumberswereamplifiedandsequenced.DatawereanalyzedusingDNAstar,DNAMAN,andMEGA4.1.TheDNAbasecompositionwasanalyzed,andthegeneticvariationsamongspeciesandwithinspecieswerecalculated.Itwasfoundthatthegeneticdistanceamongthesevenspecieswashigherthanthatwithinaspecies.Phylogeneticanalysisusingneighbor-joiningandmaximumparsimonymethodsgeneratedtreetopologiesthatindicatedthatallindividualsofeachspeciesformedastrongmonophyleticgroup.TheseresultssuggestedthatthemitochondrialgenewasavalidDNAbarcodinggeneforspeciesidentificationinseacucumbers.OnthebasisoftheDNAbarcoding,species-specificprobesofweredesigned.Dot-blothybridizationshowedthattheprobescouldidentifywithhighspecificityandsensitivity.Thedesignoffurtherprobesfordifferentseacucumberspecies,combinedwithdot-blothybridizationandmicrochipassays,willfacilitatetheidentificationofseacucumbersatrelativelylowcosts.
