Morphological And Molecular Identification Technology Of Chlorophyta In The Rocky Intertidal Zone Around Qingdao

There are various kinds of alga in the tide plot in which place that is not only the natural place for Marine organisms to live and feeding, but also the critical part of organisms structure which plays the key role, they usually call the place as "intertidal zone", There is a big wide range of them, some with significant differences on the form part, maybe they are in different stages with different life histories, While some form are almost the same but with different genetype. Such cases cause the difficulty to distinguish the species of alga in the intertidal zone such as the difficulty in classifying the species of large green algae. Taking the Ulva as the example, The thallus form of Ulva has rare differences among the others, in addition, with the green tide occurring so frequently in many places recently. The topic above causes lots of concern from algae taxonomist all over the world.The study has done the sample collection monthly, The main objects are for large green algae. For the coastal tidal zone in Qingdao and around areas, we collected green algae samples monthly in order to do the identification by morphology and molecular analysis.and the rearch is releted to the corresponding content in previous years’ research which supply scientific basis for the protection of ecological environment and the replacement of natural communities. The result is mainly divided into several parts below:First of all, we identify the species by morphological observation and microsection or frozen section, and the identification based on some special charactors such as thallus form, texture and colour; shape and form of the basal region, shape, size and arrangement of the cells. thickness of the thallus ect.And then, this research use DNA bar code technology, we select the tufA (elongation factor Tu), ITS (internal transcribed spacer), rbcL (ribulose-1,5-bisphosphate carboxylase/oxygenase large subunit) three genes to design a proper primer, we expect the fragment length of PCR amplification samples are in about800bp, according to the structure of the sequencing above three genes of the green algae we analyzed the possiblity of the use of this three genes as green algae bar code.The results show that tufA has a boarder amplicational range,and strong amplification successs rate. the sequences are divided into10clades(Ulva procera(Linzd),Ulva prolifera, Ulva flexuosa, Ulva laetevirens, Ulva compressa, Ulva australis, Ulva sp, Monostroma sp, Codium fragile, HQW-20110710-1). ITS, rbcL have higher specificity among species.and the sequences are divided into7clades each.ITS(Ulva prolifera, Ulva linza, Ulva laetevirens, Ulva australis(Ulva pertusd), Ulva compressa, Monostroma arcticum, RZ-20111206-4), rbcL(Ulva prolifera, Ulva australis(Ulva pertusa), Ulva preceral, Ulva precera2, HQW-20110902-4, ZQ-20110403-1, YT-20111205-2, Ulva laetevirens).Finally, we compare with the results of the two methods we mentioned above.and analyse the differences and the same, so we can make the identification more acurracy and show the advantages and disadvantages of the two methods.