Purpose of cultivation

Why is it useful to cultivate diatoms that you want to observe? From our point of view, the advantages are as follows:

Compared to an observation on a fresh sample, the genus and possibly the species can be identified with greater certainty and assigned to the observation.
The identification can take place independent of the observation.
The use of just one species is prerequisite for the reproducibility of experiments.
A large number of diatoms of a certain species is available. This allows investigations in which a statistical statement is the goal, such as in the case of population dynamics.
Other organisms and impurities do not interfere with the observations (see videos below).

Thus, the conditions under which one observes become well controllable. The development of a population can be investigated as a function of external parameters such as temperature, light conditions or composition of the culture medium.

Moreover, the culture vessel (e.g. petri dish) itself can be used for observation.


A sample from the river Neckar. Most striking are colonies of the diatom Bacillaria paxillifera (Bacillaria paradoxa). These colonies exhibit a unique movement based on the motility of the diatoms relative to the neighbouring diatoms. The observation is particularly affected by detritus. (4x time lapse).	View into a culture that was created with Bacillaria paxillifera from the Neckar river. The quality and the possibilities for observation are significantly improved compared to the observation in the sample. ( 4x time lapse).

On the pages on the subject of cultures we briefly describe what Mr. Kurt Schneider and I can convey from our experience. On this occasion, I would like to thank Mr. Oliver Skibbe (http://www.larger-than-life.de/micropage/start.html) for his valuable advice.