Title: | Grazer-induced morphological defense in Scenedesmus obliquus is affected by competition against Microcystis aeruginosa |
Author(s): | Zhu X; Wang J; Lu Y; Chen Q; Yang Z; |
Address: | "Jiangsu Key Laboratory for Biodiversity and Biotechnology, School of Biological Sciences, Nanjing Normal University, 1 Wenyuan Road, Nanjing 210023, China" |
ISSN/ISBN: | 2045-2322 (Electronic) 2045-2322 (Linking) |
Abstract: | "The green alga Scenedesmus is known for its phenotypic plasticity in response to grazing risk. However, the benefits of colony formation induced by infochemicals from zooplankton should come with costs. That is, a tradeoff in benefit-to-cost ratios is likely under complex environmental conditions. In this study, we hypothesized that the coexistence of Scenedesmus and its competitors decreases the formation of anti-grazer colonies in Scenedesmus. Results demonstrated that the presence of a competitor Microcystis aeruginosa inhibited inducible defensive colony formation of Scenedesmus obliquus, and the established defensive colonies negatively affected the competitive ability of S. obliquus. The proportion of induced defensive colonies in cultures was dependent on the relative abundance of competitors. Under low competition intensity, large amount of eight-celled colonies were formed but at the cost of decreased competitive inhibition on M. aeruginosa. By contrast, defensive colony formation of S. obliquus slacked in the presence of high competition intensity to maintain a high displacement rate (competitive ability). In conclusion, S. obliquus exhibited different responses to potential grazing pressure under different intensities of competition, i.e., Scenedesmus morphological response to grazing infochemicals was affected by competition against Microcystis" |
Keywords: | Animals *Ecosystem Microcystis/*physiology Scenedesmus/*physiology Zooplankton/*physiology; |
Notes: | "MedlineZhu, Xuexia Wang, Jun Lu, Yichun Chen, Qinwen Yang, Zhou eng Research Support, Non-U.S. Gov't England 2015/08/01 Sci Rep. 2015 Jul 30; 5:12743. doi: 10.1038/srep12743" |