Oscillatoria (oscillare, to swing) is very common in moist places which are rich in decaying organic matter. Such common places are ponds, streams, and other stinking moist places such as roadside ditches, drains, or sewers.
The oscillatoria is represented by 100 species. It is one of the simplest filamentous blue green algae. It forms a thin blue-green mucilaginous coating of the surface or edges of objects under flowing water.
One specie has been reported from hot spring. Some species e.g., O. princeps and O. formosa are found in association with Nitrogen-fixing Bacteria. Some common species are O. formosa, O. splendida, O. lomosa, O. prolifica.
- Class: Cyanophyceae
- Order: Oscillatoriales
- Family: Oscillatoriaceae
- Genus: Oscillatoria
Oscillatoria Structure & Morphology
It consists of a single row of cells forming trichomes or un-branched filaments with a very thin gelatinous sheath. The cells are broader than longer but cylindrical. All filament cells are similar except for the apical cell, which is convex at the top.
ln, some species may end in a subacute point or be more or less dilated, or capitated having a thickening known as a cap or calyptra at the tip.
Species with the narrow trichome, however, have cylindrical cells in which the length may be equal to or, more significant than the breadth e.g. O. splendid. If fresh material is observed under the microscope specific oscillating movement is observed.
Oscillatoria Labeled Diagram
Oscillatoria Cell Structure
All cells have a well-developed cell wall. The cell wall consists of an inner thin cellular layer a medium pectic layer and outer mucilage. The well-defined nucleus is absent. Mitochondria, endoplasmic reticulum, and Golgi bodies are also absent.
The protoplasm consists of peripheral and central cytoplasm. Pigments are found in the periphery so it is known as chromoplasm. Several small granules are also present.
Pseudo-vacuole is additionally found in some cases. Glycogen-like substance is the reserve food material. Few oil drops may also be found stored as reserve food.
Oscillatoria Under Microscope
Thesingle strain is described below:
Reproduction | Life Cycle of Oscillatoria
1. It is restricted only to vegetative reproduction, which takes place with the help of hormogones.
2. Hormogones are the parts or lengths of filaments separated from the filament by forming the separating disc.
3. Heterocyst and resting spores are not produced.
4. The trichomes which break into pieces accidentally give rise to fragments.
5. These fragments develop into new plants by cell division. Asexual and sexual reproduction is absent.