Pythiaceae

Pythiaceae
Water mould - Phytophthora forms: A: Sporangia. B: Zoospore. C: Chlamydospore. D: Oospore
Scientific classification
Domain:	Eukaryota
Clade:	Sar
Clade:	Stramenopiles
Division:	Oomycota
Class:	Peronosporomycetes
Order:	Peronosporales
Family:	Pythiaceae J. Schröt., 1893
Type genus
Pythium Pringsh., 1858
Genera
Cystosiphon Diasporangium Globisporangium Lagenidium Myzocytium Pythium Trachysphaera

Pythiaceae is a family of oomycetes. The family includes serious plant and animal pathogens in the genus Pythium. The family was circumscribed by German mycologist Joseph Schröter in 1893.

Lifecycle

• Live on land (terrestrial), and in water (aquatic), or a combination of the two (amphibious).
• Most are deadly parasites, causing root rot and damping off on plants and pythiosis on animals.
• The diploid (2N) life stage predominates, with a short haplophase initiated during sexual reproduction before the fusion of the gametes. Most species are homothallic.

Reproduction

The sporangia may germinate via a germ tube or by release of motile zoospores, depending on the species and the environmental conditions.

Economic importance

Some Pythium species cause "damping off" diseases in young plants (seedlings).

References

• C.J. Alexopolous, Charles W. Mims, M. Blackwell et al., Introductory Mycology, 4th ed. (John Wiley and Sons, Hoboken NJ, 2004) ISBN 0-471-52229-5