Spore production for Phytophthora infestans
Take agar cubes / rains from glycerol stock and place 3-4 pieces on agar plates.
When using another plate, cut small cubes (approx 0.5x0.5 cm) and place 3-4 upside down on the agar plate For longer term cultivation use RyeA agar.
For sporulation use RyeB agar.
Grow plates for about 7 days in the dark, until the plate is fully covered Optimum temperature is about 18-20°C.
Move plates to at 16/8 light/dark cycles for about 2-3 days to induce sporulation.
Harvest sporangia by adding several ml ice cold water to the plates and scraping of the sporangia with a pipette tip.
Aspirate all liquid and store in fridge for 3-6 hours to induce hatching of the spores.
Pipette off the upper layers (spores swim up, debris sink) and check spore density under microsope
