''Ganoderma orbiforme'' most commonly known as ''G. boninense'' or just ''Ganoderma'' in oil palm pathology is a species of
polypore
Polypores are a group of fungi that form large fruiting bodies with pores or tubes on the underside (see Delimitation for exceptions). They are a morphological group of basidiomycetes-like gilled mushrooms and hydnoid fungi, and not all polyp ...
fungus that is widespread across southeast Asia. It is a
plant pathogen that causes basal stem rot, a disease of the
African oil palm
''Elaeis guineensis'' is a species of palm commonly just called oil palm but also sometimes African oil palm or macaw-fat. It is the principal source of palm oil. It is native to west and southwest Africa, specifically the area between Angola a ...
(''Elaeis guineensis''). The fungus was first
described scientifically in 1838 by
Elias Magnus Fries from collections made in
Guinea.
Leif Ryvarden
Leif Randulff Ryvarden (born 9 August 1935) is a Norwegian mycologist.
Early life and education
Leif Ryvarden was born in Bergen as a son of Einar Norberg Johansen (1900–1959) and Hjørdis Randulff (1912–1975).
He finished his secondary e ...
transferred it to the genus ''
Ganoderma'' in 2000.
In addition to its
type locality, the fungus has also been collected from the
Bonin Islands
The Bonin Islands, also known as the , are an archipelago of over 30 subtropical and tropical islands, some directly south of Tokyo, Japan and northwest of Guam. The name "Bonin Islands" comes from the Japanese word ''bunin'' (an archaic read ...
in the Pacific, and from Venezuela and Puerto Rico.
Transmission
''G. orbiforme'' is not a
soil borne pathogen A soil borne pathogen is a disease-causing agent which lives both in soil and in a plant host, and which will tend to infect undiseased plants which are grown in that soil. Common soil borne pathogens include ''Fusarium'', ''Pythium'', ''Rhizocton ...
, meaning it does not grow in soil and does not infiltrate from soil and into the root system.
It is however also not killed by soil, and will reside in dead, buried palm trunk material.
This has especially been observed when ''
Oryctes rhinoceros''-infested material was buried.
Infection
''G. orbiforme'' has a
hemibiotrophic lifestyle in ''E. guineensis''.
During an invasion, ''E. guineensis'' roots stockpile
salicylic acid, which is a signal to downregulate its own expression of
ascorbate oxidase and
ascorbate peroxidase.
AO and AP are
reactive oxygen species scavengers, and so the total effect is to increase
ROS production.
This entire pathway was found by Ho ''et al.'', 2016.
Increased ROS is effective against hemibiotrophs but counterproductive against
necrotrophs.
Genetics
Microsatellite markers have been developed to help identify the fungus and study the
genetic diversity of ''G. orbiforme''.
Research
Water agar is usable for
isolation of this fungus, and is the simplest and cheapest.
provides research and
technique information for lab work with this pathogen.
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References
External links
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{{Taxonbar, from=Q5521450
Fungi described in 1838
Fungi of Africa
Fungi of Asia
Fungi of South America
Fungal plant pathogens and diseases
Ganoderma
Taxa named by Elias Magnus Fries
Pests of oil palm