Allelopathic inhibition of phytoplankton by exudates from Stratiotes aloides
In: Aquatic Botany. Elsevier Science: Tokyo; Oxford; New York; London; Amsterdam. ISSN 0304-3770; e-ISSN 1879-1522, more | |
Keywords | Biological competition > Plant competition > Plant interaction > Allelopathy Irradiance Population functions > Growth Stratiotes aloides Netherlands [Marine Regions] Fresh water | Author keywords | allelopathy; exudate; growth inhibition; initial biovolume doublingtime; irradiance; lag phase |
Authors | | Top | - Mulderij, G.
- Mooij, W.M., more
- Smolders, A.J.P.
- Van Donk, E.
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Abstract | The allelopathic potential of exudates from the aquatic macrophyte Stratiotes aloides on the growth of phytoplankton was investigated. A selection of phytoplankton species, occurring in habitats similar to that of Stratiotes, was used: two cyanobacterial strains (toxic and non-toxic Microcystis aeruginosa), one green alga (Scenedesmus obliquus) and one eustigmatophyte (Nannochloropsis limnetica). The results indicate allelopathic effects of Stratiotes on phytoplankton in six of the eight cases, expressed in an extended duration of the initial biovolume doubling time. The overall inhibitory effect (8–51%) was strain-specific for the two cyanobacteria. We also studied the effect of irradiance on the allelopathic potential of exudates from Stratiotes. Irradiance influenced the response of Scenedesmus only. The inhibitory effect of Stratiotes exudates on the growth of this green alga was stronger at 35 μmol m−2 s−1 than at 105 μmol m−2 s−1. We conclude that Stratiotes has allelopathic effects on phytoplankton, and that irradiance can, but does not always determine the extent of the allelopathic inhibition. In our experiments, the sensitivity of cyanobacteria to Stratiotes exudates was not higher than for other phytoplankton strains, but within cyanobacteria, the toxic strain was more sensitive than the non-toxic one. |
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