Secondments of Chahinez HamediFrom UO to US

 

The morphological identification of diatom species is often done by optical microscopy and Scanning Electron Microscopy, in the other hand, the small size of some diatoms and the closer structural similarity make identification of genus or species difficult.

 

Morphology is not always a reliable indicator of species boundaries. However, the development of molecular technologies made a revolution in the yield of diatoms and several DNA-markers are evaluated (18S, cox1, ITS, rbcL) due to their good results in differentiating species. For the phylogeny of diatoms the marker rbcL tends to be the most used. It is both informative and conservative, and many sequences are already available on the databases.

 

During my secondment in Szczecin University, we were able to identify four species of diatoms isolated from the Oranian coast, using a combination of optical microscopy and Scanning Electron Microscopy.