Heteroecious

{{Use dmy dates|date=October 2023}} {{short description|Several-host parasite}} [[File:Melampsora-larici-populina life cycle.jpg|thumb|''Melampsora laricis-populina'' life cycle. (a) Biological macrocyclic heteroecious cycle of ''M. larici-populina''. (b) Vegetative cycle occurring on poplar leaves and used as a model for molecular investigations of the poplar-poplar rust interaction. hpi=hours of postinoculation.]] A '''heteroecious''' parasite is one that requires at least two hosts. The ''primary host'' is the host in which the parasite spends its adult life; the other is the ''secondary host''. Both hosts are required for the parasite to complete its life cycle. This can be contrasted with an '''autoecious''' parasite which can complete its life cycle on a single host species. Many rust fungi have heteroecious life cycles:<ref>Schumann, G. & D'Arcy, C. (2010). Essential plant pathology. APS Press</ref>

In parasitology, '''heteroxeny''', or heteroxenous development, is a synonymous term that characterizes a parasite whose development involves several hosts.<ref name="Odening1976">{{Cite book |last1=Odening |first1=Klaus |chapter=Conception and terminology of hosts in parasitology |editor1-last=Dawes |editor1-first=Ben |volume=14 |pages=24–25 |chapter-url=https://books.google.com/books?id=rcRtCavuUYEC&pg=PA24 |title=Advances in Parasitology |date=20 January 1976 |publisher=Academic Press |isbn=978-0-08-058060-9 |language=en |access-date=2 October 2020 |archive-date=26 October 2023 |archive-url=https://web.archive.org/web/20231026175413/https://books.google.com/books?id=rcRtCavuUYEC&pg=PA24#v=onepage&q&f=false |url-status=live }}</ref>

== Fungal examples == * ''Gymnosporangium'' (Cedar-apple rust): the juniper is the primary (telial) host and the apple, pear or hawthorn is the secondary (aecial) host. * ''Cronartium ribicola'' (White pine blister rust): the primary host are white pines, and currants the secondary. * ''Hemileia vastatrix'' (Coffee rust): the primary host is coffee plant, and the alternate host is unknown. * ''Puccinia graminis'' (Stem rust): the primary hosts include Kentucky bluegrass, barley, and wheat; barberry is the alternate host. * ''Puccinia coronata'' var. ''avenae'' (Crown rust of oats): Oats are the primary host; ''Rhamnus'' spp. (Buckthorns) are the alternate hosts. * ''Phakopsora meibomiae'' and ''P. pachyrhizi'' (Soybean Rust): the primary host is soybean and various legumes. The alternate host is unknown. * ''Puccinia porri'' (Leek rust): autoecious

==History== The phenomenon of '''heteroecy''' was first discovered by A.S. Ørsted in 1863.<ref>Ørsted, A.S. (1863) Om Sygdomme hos Planterne, som foraarsages af Snyltesvampe, navnlig om Rust og Brand og om Midlerne til deres Forebyggelse. Kjøbenhavn</ref>

==References== {{reflist}}

Category:Parasitology