''Ophiostoma himal-ulmi'' is a species of

fungus A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from th ...

in the family

Ophiostomataceae The Ophiostomataceae are a family (biology), family of fungi in the Ascomycota, class Sordariomycetes. The family was circumscription (taxonomy), circumscribed by John Axel Nannfeldt, J.A. Nannfeldt in 1932. Species in the family have a wide ...

. It is one of the causative agents of

Dutch elm disease Dutch elm disease (DED) is caused by a member of the sac fungi (Ascomycota) affecting elm trees, and is spread by elm bark beetles. Although believed to be originally native to Asia, the disease was accidentally introduced into Americas, America ...

. It was first isolated around breeding galleries of scolytid

beetles Beetles are insects that form the order Coleoptera (), in the superorder Endopterygota. Their front pair of wings are hardened into wing-cases, elytra, distinguishing them from most other insects. The Coleoptera, with about 400,000 describ ...

in the bark of ''

Ulmus wallichiana ''Ulmus wallichiana'' Planch., the Himalayan elm, also known as the Kashmir elm and Bhutan elm, is a mountain tree ranging from central Nuristan in Afghanistan, through northern Pakistan and northern India to western Nepal at elevations of 800&n ...

'' (the Himalayan elm). This, together with the fact that it is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...

to the

Himalayas The Himalayas, or Himalaya (; ; ), is a mountain range in Asia, separating the plains of the Indian subcontinent from the Tibetan Plateau. The range has some of the planet's highest peaks, including the very highest, Mount Everest. Over 100 ...

, is the reason it is named ''himal-ulmi'' (‘of the Himalayan elm’; means ‘of the elm’). It is

outcrossing Out-crossing or out-breeding is the technique of crossing between different breeds. This is the practice of introducing distantly related genetic material into a breeding line, thereby increasing genetic diversity. Outcrossing can be a useful ...

and

heterothallic Heterothallic species have sexes that reside in different individuals. The term is applied particularly to distinguish heterothallic fungi, which require two compatible partners to produce sexual spores, from homothallic ones, which are capable of ...

, with two sexual compatibility types: A and B, occurring in a near 1:1 ratio in nature. It also exhibits a distinctive colony type, an ability to produce

synnemata A synnema (plural ''synnemata'', also ''coremia''; derivation: "Threads together") is a large, erect reproductive structure borne by some fungi, bearing compact conidiophore A conidium ( ; ), sometimes termed an asexual chlamydospore or chlamy ...

malt extract Malt is germinated cereal grain that has been dried in a process known as "malting". The grain is made to germinate by soaking in water and is then halted from germinating further by drying with hot air. Malted grain is used to make beer, whis ...

agar Agar ( or ), or agar-agar, is a jelly-like substance consisting of polysaccharides obtained from the cell walls of some species of red algae, primarily from ogonori (''Gracilaria'') and "tengusa" (''Gelidiaceae''). As found in nature, agar is ...

, production of

perithecia An ascocarp, or ascoma (), is the fruiting body ( sporocarp) of an ascomycete phylum fungus. It consists of very tightly interwoven hyphae and millions of embedded asci, each of which typically contains four to eight ascospores. Ascocarps are mo ...

with long necks, a very high level of cerato-ulmin toxin production in liquid shake cultures, and moderate to strong vascular wilt pathogenicity on ''

Ulmus procera The field elm (''Ulmus minor'') cultivar 'Atinia' , commonly known as the English elm, formerly common elm and horse may, Republished 1978 by EP Publishing, Wakefield. and more lately the Atinian elm was, before the spread of Dutch elm disea ...

''.

References

External links

* Fungi described in 1995 Fungal tree pathogens and diseases Ophiostomatales {{Sordariomycetes-stub

References

Further reading

External links