In Experiment 1, none of the N. flexilis oospores inoculated into Petri plates and culture tubes containing either agar or water and then exposed to ‘normal’ 12 h daylight 12 h dark germinated when the redox of the media remained relatively constant over the 20-day observation period, while all of the oospores in a tube in which the redox of the agar declined to below 200 mV, germinated. Similarly no germination occurred in the dark without a decrease in redox. When redox fell to below 200 mV, 11% of the inoculated oospores germinated.

In Experiment 2, N. flexilis and C. vulgaris oospores were subjected to cold pre-treatments and inoculated into either water or agar in both plates and tubes. Of the N. flexilis oospores 53% germinated in the dark, and 31% under normal lighting. Of the C. vulgaris, 3% germinated in the dark and 53% under normal lighting. The stimulation of germination with the decrease in redox in the media did not re-occur.