Batch experiments to examine predation by and growth of the flagellate Ochromonas sp. strain DS with strain MWH-Mo1a

PrepnNo. of replicatesIncubation conditionsPrey 1Prey 2
StrainInitial no. (106 cells ml−1) (SD)Final no. (106 cells ml−1) (SD)StrainInitial no. (106 cells ml−1)Final no. (106 cells ml−1)
Expt 1
    Expt 13IlluminationMWH-Mo114.0 (0.6)10.1 (1.2)bNone
    Control 13Illumination Pseudomonas sp.13.8 (1.4)0.0cNone
Expt 2
    Expt 23DarknessMWH-Mo118.2 (1.7)12.7 (0.4)dNone
    Control 2a−NoneDarkness Pseudomonas sp.7.40.0eNone
    Control 2a+NoneDarkness Pseudomonas sp.8.10.0eMWH-Mo10.0810.4f
    Control 2b−NoneDarkness B. diminuta 7.10.0fNone
    Control 2b+NoneDarkness B. diminuta 7.00.0fMWH-Mo10.073.2f
  • a All preparations were initially inoculated with low numbers of Ochromonas sp. strain DS cells (experiment 1, 1.3 × 103 cells ml−1; experiment 2, 2.7 × 103 cells ml−1). Two of the control preparations received in addition to the prey bacteria low numbers of strain MWH-Mo1 cells. All preparations were incubated at 15°C without shaking. Sampling of the control preparations was stopped after 20 days, while samples were obtained from the experimental preparations for 38 days (experiment 1) and 35 days (experiment 2).

  • b Data obtained on day 38.

  • c Data obtained on day 4.

  • d Data obtained on day 20 (before addition of heat-killed Pseudomonas sp. [Fig. 4]).

  • e Data obtained on day 5.

  • f Data obtained on day 20.