Priority effects in experimental populations of the cyanobacterium Microcystis |
| |
Authors: | Ineke van Gremberghe Pieter Vanormelingen Katleen Van der Gucht Caroline Souffreau Wim Vyverman Luc De Meester |
| |
Affiliation: | Laboratory of Protistology and Aquatic Ecology, Ghent University, Krijgslaan 281 –S8, 9000 Ghent, Belgium.; Laboratory of Aquatic Ecology and Evolutionary Biology, Katholieke Universiteit Leuven, Charles Debériotstraat 32, 3000 Leuven, Belgium. |
| |
Abstract: | The arrival order of colonists in developing populations can have a lasting influence on community and population structure, a phenomenon referred to as priority effects. To explore whether such priority effects are important in determining strain composition of populations of the cyanobacterium Microcystis , four Microcystis strains, isolated from a single lake and differing in functional traits, were grown during 4 weeks in the laboratory in all possible pairwise combinations, with the two strains either inoculated at the same time or with a time lag of 1 week, in the presence or absence of grazing Daphnia magna . The relative abundance of strains in the mixtures was assessed using denaturing gradient gel electrophoresis, and the growth rate of each strain in the mixtures was determined for the last 2 weeks of the experiment. We observed strong effects of inoculation order on the final population structure, and these effects were influenced by grazing Daphnia . The priority effects were strain-specific and occurred in two directions: some of the strains grew slower while others grew faster when inoculated second compared with when inoculated first. Our results indicate that priority effects may have a profound impact on strain composition of Microcystis populations. |
| |
Keywords: | |
|
|