Damping-off
that are in a sub-optimal condition or suffer from stress, caused for example by too much water, too high or low temperatures or sudden fluctuations in temperature [...] conditions, especially dehydration. Germination of the oospores is stimulated by exudates from roots of a susceptible host nearby. The oospores germinate and [...] or substrate. Oospores are dispersed when soil particles are moved around by humans or machinery. Pythium can survive very well in the soil or substrate