cultivation
In the biological sense, cultivation is the creation and maintenance of conditions that ensure the growth of certain organisms . Often this is also associated with their increase. Very different organisms are cultivated. Typical examples of this are the cultivation of crops in agriculture or horticulture and the cultivation of bacteria in a Petri dish .
Not only whole organisms can be cultivated, but also parts of them, such as certain cells or tissues of plants and animals. Thus, the cultivation of animal or plant cells - i.e. cells of eukaryotes - in a nutrient medium outside the organism is possible, this is called cell culture . A frequently used method is the plant tissue culture , in which complete plants are formed from pieces of tissue from the plants, sometimes also via a secondary callus culture .
Depending on the purpose, liquid or gelled culture media are used for the culture of microorganisms . In the cultivation of animal cells, liquid nutrient media are primarily used, and gel nutrient media (“solid” nutrient media) for plant cells . A gel culture medium is created by adding a gelling (“solidifying”) substance to a culture medium, which does not serve as a source of food for the respective organism. The best-known example is agar , other solidifiers are gellan and silica gel . A direct comparison of agar and gellan shows that these agents are by no means inert during cultivation, but rather influence the physiology of, for example, plant cell cultures.
In the case of microorganism culture, a distinction is made between various culture techniques, of which the pure culture , the enrichment culture , the liquid culture and the culture on gel nutrient media are among the most important. These methods can be used, for example, to isolate a microorganism clone from a microorganism community with many different types of microorganisms in order to detect the presence of a particular species or to investigate it more closely. In medical microbiology this plays a special role in relation to pathogens .
Individual evidence
- ↑ Dieter Heß: Biotechnology of the plant. An introduction . 1st edition. UTB Ulmer Verlag, Stuttgart 1992, ISBN 978-3-8252-8060-4 .
- ↑ Birgit Hadeler, Sirkka Scholz, Ralf Reski : Gelrite and agar differently influence cytokinin-sensitivity of a moss . In: Journal of Plant Physiology . Vol. 146, 1995, pp. 369-371.
- ↑ Eckhard Bast: Microbiological Methods: An Introduction to Basic Working Techniques . 2nd Edition. Spektrum Akademischer Verlag GmbH, Heidelberg / Berlin 2001, ISBN 978-3-8274-1072-6 .