AME 71:257-269 (2014)  -  DOI:

Prey element stoichiometry controls ecological fitness of the flagellate Ochromonas danica

Thomas H. Chrzanowski*, Briony L. L. Foster

Department of Biology, PO Box 19498, The University of Texas Arlington, Arlington, Texas 76019, USA
*Corresponding author:

ABSTRACT: In aquatic systems, the protist-bacteria consumer-resource interaction is one of the few interactions that link and regulate the flow of dissolved nutrients to higher trophic levels. While this interaction is well characterized from the perspective of top-down control of bacteria, less understood is how the interaction may regulate consumer success. Here, we consider the protist-bacteria consumer-resource interaction and explore relationships among food quality (measured as ratios of C:N, C:P, or N:P), prey type (measured by prey-size and taxonomic affiliation), and consumer success (measured by growth rate). We use a model consumer, the flagellate Ochromonas danica, and a variety of bacterial species as resources. Rates at which prey were ingested corresponded to prey quality for metrics of food quality based on C (C:N and C:P). Prey quality also strongly influenced consumer fitness. A large imbalance between the element ratio of the consumer and that of its prey had a negative impact on consumer fitness, particularly when excess C or excess N was consumed. Prey type, as a phylogenetic group of bacteria, also influenced consumer success. Betaproteobacteria were readily consumed but failed to support consumer growth, mainly as a result of a nutrient imbalance between consumer and resource.

KEY WORDS: Bacterivory · Food quality · Ecological stoichiometry · Prey selection

Full text in pdf format 
Cite this article as: Chrzanowski TH, Foster BLL (2014) Prey element stoichiometry controls ecological fitness of the flagellate Ochromonas danica. Aquat Microb Ecol 71:257-269.

Export citation
Mail this link - Contents Mailing Lists - RSS
- -