Effects of nutrient availability and Ochromonas sp predation on size and composition of a simplified aquatic bacterial community

被引:25
作者
Corno, Gianluca
机构
[1] CNR, Inst Ecosyst Study, I-28922 Verbania Pallanz, Italy
[2] Max Planck Inst Limnol, Plon, Germany
关键词
grazing on bacteria; prey-predator interaction; phenotypic adaptation; filament; microcolony;
D O I
10.1111/j.1574-6941.2006.00185.x
中图分类号
Q93 [微生物学];
学科分类号
071005 ; 100705 ;
摘要
Predation and competition are two main factors that determine the size and composition of aquatic bacterial populations. Using a simplified bacterial community, composed of three strains characterized by different responses to predation, a short-term laboratory experiment was performed to evaluate adaptations and relative success in communities with experimentally controlled levels of predation and nutrient availability. A strain with a short generation time (Pseudomonas putida), one with high plasticity in cell morphology (Flectobacillus sp. GC5), and one that develops microcolonies (Pseudomonas sp. CM10), were selected. The voracious flagellate Ochromonas sp. was chosen as a predator. To describe adaptations against grazing and starvation, abundance, biomass and relative heterogeneity of bacteria were measured. On the whole, the strains in the predation-free cultures exhibited unicellular growth, and P. putida represented the largest group. The presence of Ochromonas strongly reduced bacterial abundance, but not always the total biomass. The activity of grazers changed the morphological composition of the bacterial communities. Under grazing pressure the relative composition of the community depended on the substrate availability. In the presence of predators, P. putida abundance declined in both high and low nutrient treatments, and Pseudomonas CM10 developed colonies. Flectobacillus was only numerically codominant in the nutrient-rich environments.
引用
收藏
页码:354 / 363
页数:10
相关论文
共 44 条
[1]   EFFECT OF INCREASED PRODUCTIVITY ON THE ABUNDANCES OF TROPHIC LEVELS [J].
ABRAMS, PA .
AMERICAN NATURALIST, 1993, 141 (03) :351-371
[2]   Are readily culturable bacteria in coastal North Sea waters suppressed by selective grazing mortality? [J].
Beardsley, C ;
Pernthaler, J ;
Wosniok, W ;
Amann, R .
APPLIED AND ENVIRONMENTAL MICROBIOLOGY, 2003, 69 (05) :2624-2630
[3]   Bacterivory by heterotrophic flagellates: community structure and feeding strategies [J].
Boenigk, J ;
Arndt, H .
ANTONIE VAN LEEUWENHOEK INTERNATIONAL JOURNAL OF GENERAL AND MOLECULAR MICROBIOLOGY, 2002, 81 (1-4) :465-480
[4]  
Boenigk J, 2001, MICROB ECOL, V42, P168
[5]   GRAZING OF ATTACHED BACTERIA BY HETEROTROPHIC MICROFLAGELLATES [J].
CARON, DA .
MICROBIAL ECOLOGY, 1987, 13 (03) :203-218
[6]   Measurement of bacterivory by heterotrophic nanoflagellates using immunofluorescence labelling of ingested cells [J].
Christoffersen, K ;
Nybroe, O ;
Jurgens, K ;
Hansen, M .
AQUATIC MICROBIAL ECOLOGY, 1997, 13 (01) :127-134
[7]   Direct and indirect effects of protist predation on population size structure of a bacterial strain with high phenotypic plasticity [J].
Corno, G ;
Jürgens, K .
APPLIED AND ENVIRONMENTAL MICROBIOLOGY, 2006, 72 (01) :78-86
[8]   Effect of nutrient supply on the biomass structure of planktonic communities:: an experimental test on a Mediterranean coastal community [J].
Duarte, CM ;
Agustí, S ;
Gasol, JM ;
Vaqué, D ;
Vazquez-Dominguez, E .
MARINE ECOLOGY PROGRESS SERIES, 2000, 206 :87-95
[9]  
Fenchel T, 1987, ECOLOGY PROTOZOA BIO, P32, DOI 10.1007/978-3-662-25981-8_3
[10]   Regulation of bacterial assemblages in oligotrophic plankton systems:: results from experimental and empirical approaches [J].
Gasol, JM ;
Pedrós-Alió, C ;
Vaqué, D .
ANTONIE VAN LEEUWENHOEK INTERNATIONAL JOURNAL OF GENERAL AND MOLECULAR MICROBIOLOGY, 2002, 81 (1-4) :435-452