Karyotype Analysis of Desmodesmus pannonicus with Scanning Electron Microscope (SEM)

The genus Desmodesmus commonly contain polymorphic species in the plankton of different freshwater basins. Since the identification of many taxa in the Scenedesmaceae family is not clear and Desmodesmus sp. are pleomorphic creatures that change according to stress factors, morphological nomenclature needs to be supported by karyological studies. The chromosome morphology of the alga Desmodesmus pannonicus has 14 chromosomes: four big metacentric chromosomes, five big submetacentric chromosomes, 2 small metacentric chromosomes and 3 submetacentric chromosomes. The karyotype formula is 9(4M + 5SM) + 5(2m + 3sm). The total average metaphase length of the haploid set is 13.716 ± 0.223 µm. This study was aimed to carry out karyotype of Desmodesmus pannonicus using an electron microscope (SEM TESCAN Vega II CZ), which allows chromosome lengths to be visualized and calculated more accurately.