FIG. 7.

Excystment and proliferation of cells of P. piscicida and the Pfiesteria-like complex from environmental sediments. The sediment from two different fish ponds (samples 1 [left panel] and 10 [right panel], corresponding to the samples in Fig. 6) in 50-ml suspensions was incubated in flasks with total volumes of 450 ml under various conditions: (i) with ASW and an adult fish (○; w/fish), (ii) with ASW alone (•; wo/fish), and (iii) with f/2 medium (□; w/medium). Throughout 29 days of incubation at 23°C under a standard light cycle, water samples were collected for counting (1 ml) and PCR detection (15 ml). (A) Densities of emerged P. piscicida-like complex cells in the water column (error bars, standard deviations; n, 3 replicate experiments). (B) Detection of emerged P. piscicida cells by species-specific PCR. (C) QC-PCR assessment of densities of P. piscicida cells emerging from environmental sediment sample 10. The emergence and proliferation of P. piscicida cells in the presence of ASW and an adult fish (○), ASW only (•), and f/2 medium (□) were detected and assessed.