FLV tracer assays Prepare FLVs for tracer assays.
Collect seawater samples from the desired location.
After determining the concentration of the FLVs in the concentrate, and the ambient concentration of viruses in the seawater, the proper amount of FLV concentrate should be added at tracer levels (<10% of original ambient virus concentration) into sample volumes of no less than 400 mL.
Designate a control treatment.
At each time point, total viral abundance and FLV numbers should be determined in duplicate from small volume subsamples (5–30 mL) taken into sterile, 15- or 50-mL polyethylene tubes.
Subsamples are immediately fixed with 1% to 2% (final concentration) 0.02-µm filtered formalin and stored at 4°C.
Slides should be prepared according to Noble and Fuhrman (1998) or Patel et al. (2007).
Production and removal rates are calculated from the equations of Glibert et al. (1982) and Fuhrman (1987) (see guidelines for equations).
