Contamination of diatom cultures with other microorganisms

During establishing and maintenance of diatom cultures one have to solve the problem of their contamination by other organisms, from viruses, mycoplasma and bacteria, to protozoa and metazoa. Depending on the task to be solved, it is advisable to use cultures of different degrees of purity, from mono-species (algologically pure) to axenic. Contamination of cultures can be initial (primary) and random in the process of cutivation (secondary). Examples of contamination are discussed, in particular with the kinetoplastid Bodo saltans.