Influence of Biotic and Abiotic Factors on the Allelopathic Activity of the Cyanobacterium Cylindrospermopsis raciborskii Strain LEGE 99043
- 459 Downloads
Allelopathy is considered to be one of the factors underlying the global expansion of the toxic cyanobacterium Cylindrospermopsis raciborskii. Although the production and release of allelopathic compounds by cyanobacteria is acknowledged to be influenced by environmental parameters, the response of C. raciborskii remains generally unrecognized. Here, the growth and allelopathic potential of C. raciborskii strain LEGE 99043 towards the ubiquitous microalga Ankistrodesmus falcatus were analyzed under different biotic and abiotic conditions. Filtrates from C. raciborskii cultures growing at different cell densities displayed broad inhibitory activity. Moreover, higher temperature, higher light intensity as well phosphate limitation further enhanced this activity. The distinct and comprehensive patterns of inhibition verified during the growth phase, and under the tested parameters, suggest the action of several, still unidentified allelopathic compounds. It is expectable that the observed increase in allelopathic activity can result in distinct ecological advantages to C. raciborskii.
KeywordsCell Density High Light Intensity Lower Cell Density Initial Cell Density Cellular Density
The authors thank Lúcia Guilhermino for access to the spectrophotometer and Aldo Barreiro for statistical advice. PNL acknowledges a postdoctoral scholarship from Fundação para a Ciência e a Tecnologia (SFRH/BPD/70233/2010).
- 1.Arar EJ (1997) In vitro determination of Chlorophyll a, b, c1 and c2, and Pheopigments in marine and freshwater phytoplankton by spectrophotometry. EPA, Cincinnati EPA method 446.0)Google Scholar
- 21.Kotai J (1972) Instructions for the preparation of modified nutrient solution Z8 for algae. Oslo: Norwegian Institute for Water Research Blindern NIVA B-11/69Google Scholar
- 22.Krüger T, Hölzel N, Luckas B (2011) Influence of cultivation parameters on growth and microcystin production of Microcystis aeruginosa (Cyanophyceae) isolated from Lake Chao (China). Micro Ecol. doi: 10.1007/s00248-011-9899-3
- 31.Padisák J (1997) Cylindrospermopsis raciborskii (Woloszynska) Seenayya et Subba Raju, an expanding, highly adaptive cyanobacterium: worldwide distribution and review of its ecology. Arch Hydrobiol Suppl 107:563–593Google Scholar
- 41.Utermöhl H (1958) Zur Vervollkommung der quantitativen Phytoplankton-Methodik. Mitt Int Ver Limnol 9:1–38Google Scholar
- 43.Vrba J, Komarkova J, Vyhnalek V (1993) Enhanced activity of alkaline phosphatases phytoplankton response to epilimnetic phosphorus depletion. Water Sci Technol 28:15–24Google Scholar