CS39A Zooplankton - Feeding, Reproduction, Growth and Molecular Diversity
Date: Tuesday, June 11, 2002
Location: Poster Session - VCC
 
NejstgaardJC, University of Bergen, Bergen, Norway, jens.nejstgaard@ifm.uib.no
Frischer, M, E, Skidaway Institute of Oceanography, Savannah, GA, USA, frischer@skio.peachnet.edu
Raule, C, L, Skidaway Institute of Oceanography, Savannah, GA, USA, raule@skio.peachnet.edu
Verity, P, G, Skidaway Institute of Oceanography, Savannah, GA, USA, peter@skio.peachnet.edu
 
AMPLIFYING PREY RIBOSOMAL RNA GENES: A PROMISING METHOD FOR DETERMINEING COMPLEX ZOOPLANKTON FEEDING INTERACTIONS
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The ability to adequately determine trophic interactions is vital for understanding mechanisms that structure complex aquatic ecosystems. But despite decades of research, precise and rapid methods to quantify selective feeding of the entire prey range by zooplankton in situ are still lacking. Several different qualitative genetic techniques, based on the polymerase chain-reaction (PCR), have been successfully applied in studies of carnivory in insects. Compared to those insects, zooplankton such as copepods have a simpler gut structure, relatively neutral gut pH, and shorter digestion time. Since DNA is much more prey-specific and less easily oxidized than plant pigments, we suggest that prey DNA should have a much larger potential as a quantitative prey tracer in zooplankton guts and faecal pellets, than the widely used plant pigments. Here we show the first results of successful extraction and PCR amplification of algal 18S ribosomal DNA from calanoid copepod faecal pellets. The PCR-products from closely related prey algae species and pure copepod extracts were unambiguously differentiated from the target prey.