Chilling the water also helps to prevent pathogens such as pythium, and delay bolting. Seedlings may be killed by "Pythium" damping off. Root rot ("Pythium") has been reported. In field crops, damage by "Pythium" spp. Several cultural management methods can be effective in avoiding disease caused by "Pythium aphanidermatum". Other commonly responsible pathogens include "Pythium", "Rhizoctonia", and "Fusarium". This trait is also exhibited by most "Pythium" spp. Sterilized potting soil will minimize problems with "Botrytis" or "Pythium" fungal disease. Pythium insidiosum is a species of "Pythium" and a member of the class oomycota. Genetic resistance involves finding species of plant that are not susceptible to "Pythium graminicola". The family includes serious plant and animal pathogens in the genus "Pythium". The mycelium found on foliage is often confused with that of "Pythium", "Nigrospora", and "Rhizoctonia". "C. crispus" is susceptible to infection from the oomycete "Pythium porphyrae". Types include pythiosis (caused by "Pythium insidiosum") and lagenidiosis. Fungus that causes stem rot are in the "Rhizoctonia", "Fusarium" or "Pythium" genera.