Synchytrium endobioticum
Synchytrium endobioticum
Synchytrium endobioticum is, wart disease -causing fungus potty. It can also affect other solanaceous plants, but the potato is the only infectable crop.
There are at least 18 pathotypes of the fungus, with most in Central Europe have only a limited distribution. The most widespread pathotype has first
Morphology
Like some other Chytridiales developed the fungal mycelium no. He developed a " winter sporangium " designated, thick-walled structure. She is 25-75 microns thick and contains 200-300 spores. The sporangia are grouped in thin-walled Sori. The movable zoospore has a diameter of approximately 0.5 microns and has a posterior flagellum.
Life cycle
The overwintering sporangia germinate in the spring at the higher temperatures at high humidity. They released zoospores which infect appropriate host cells. The summer sporangia develop in the infected cells, which quickly dismiss new populations and zoospores. The infection cycle continues for as long as the living conditions for the fungus are suitable. Infested plants cells swell, divide and surround the dividing zoospores, which has the visible warts formation.
Under certain stress conditions merge pairs of zoospores zygote. The zygote containing cells divide and eventually form the wall of a new winter sporangium from. In the fall expire warts, where they released new, thick-walled spores in the soil. These diploid, overwintering spores undergo a resting phase. Prior to germination find (probably) instead of a meiotic division and a few mitotic divisions, resulting in the sorus at the end.
Ecology
There are three different known fungi that can affect the resting sporangium parasitic. He is a unicellular, soil-borne, obligate parasitic fungus living. His preferred environmental conditions are moderate temperatures (not above 20 ° C) with adequate moisture. An infested potato can be recognized by typical growths.
The spores can survive in the soil to a depth of 50 cm. Winter spores can remain viable 20-40 years, which are very heat - but also very cold tolerant. Due to the resistance of the spores can cause a disease spread by animal feces by feeding of infected potatoes. Therefore applies a perpetual cultivation lock on an affected acreage. A carry is possible through contaminated farm equipment beyond.
The fungus has its origin in the Andean region of South America, however, has now spread out almost everywhere in the world where potatoes are grown, but not in most tropical regions of Africa, the Middle East, Canada, Japan and Australia.
The fungus is a threat for potato cultivation because it can not be fought. There are, however, resistant potato varieties.
Swell
- Bavarian State Research Center for Agriculture
- Resting - spore germination in Synchytrium endobioticum
- Germination and parasitation of the resting sporangia of Synchytrium endobioticum
- About waiting potato disease
- Mushrooms
- Fungi