Applications of flow cytometry to phytoplankton research

Abstract

Flow cytometers are capable of rapidly measuring multiple optical parameters on individual phytoplankton cells. For example, chlorophyll a, accessory pigment and fluorescein fluoresence can be measured simultaneously along with forward and side light scatter. Each of these optically expressed features can be probed to provide insight into phytoplankton physiology; their response to environmental conditions and to provide an estimate of within-population variability. This paper contains a summary of techniques that were developed to identify nutrient-limited populations, to determine the impact of mine drainage, to measure relative gas vesicle volume of cyanobacteria and to provide an estimate of within-population variability. Flow cytometry proved a powerful tool in each of these investigations, particularly when combined with metabolic probes (e.g. FDA), to estimate photosynthesis and growth rates.