|Allelopathic growth inhibition and colony formation of the green alga Scenedesmus obliquus by the aquatic macrophyte Stratiotes aloides|
Mulderij, G.; Mooij, W.M.; Van Donk, E. (2005). Allelopathic growth inhibition and colony formation of the green alga Scenedesmus obliquus by the aquatic macrophyte Stratiotes aloides. Aquat. Ecol. 39(1): 11-21
In: Aquatic Ecology. Springer: Dordrecht; London; Boston. ISSN 1386-2588, more
|Authors|| || Top |
- Mulderij, G.
- Mooij, W.M., more
- Van Donk, E.
Laboratory experiments were conducted to elucidate the allelopathic effects of exudatesfrom the aquatic macrophyte Stratiotes aloides on the growth and morphology of thegreen alga Scenedesmus obliquus. Both water originating from a S. aloides culture andwater that had not been in contact with S. aloides were simultaneously inoculated withS. obliquus cells in both cases. In all experiment we observed a highly significantinhibitory effect of Stratiotes water on the green alga. The duration of the lag phase aswell as initial biovolume doubling time of S. obliquus were extended. The growth rate ofS. obliquus was only significantly inhibited by the younger Stratiotes plants.Furthermore, the mean particle volume (MPV) of Scenedesmus increased significantlyin the presence of Stratiotes water in all three experiments. Microscopic analysesconfirm that S. obliquus forms more colonies in the presence of water from a S. aloidesculture. Colonies of phytoplankton have higher sinking rates than single phytoplanktoncells of the same species and disappear faster from the upper water layers, reducingthe competitive advantage of algae for light against macrophytes.