Botrychium

Botrychium
Moonwort
Botrychium lunaria
Scientific classification
Kingdom: Plantae
Division: Pteridophyta
Class: Psilotopsida
Order: Ophioglossales
Family: Botrychiaceae
Genus: Botrychium
Sw.
Species

Several, see text

Moonworts are ferns, seedless vascular plants, of the genus Botrychium, sensu stricto. They are small, with fleshy roots, and reproduce by spores shed into the air. One part of the leaf, the trophophore, is sterile and fernlike; the other, the sporophore, is fertile and carries the clusters of sporangia or spore cases. Some species only occasionally emerge above ground and gain most of their nourishment from an association with mycorrhizal fungi. They are unusual among tracheophytes ("higher plants") in that at least some species produce the sugar trehalose.

The circumscription of Botrychium is disputed between different authors; some botanists include the genera Botrypus and Sceptridium within Botrychium, while others treat them as distinct. The latter treatment is provisionally followed here.

Selected species

Botrychium lunarioides in beech/oak forest in northern Florida; March 2003.

Conservation

Moonworts can be found in many environments, including prairies, forests, and mountains. While some Botrychium species are quite rare, conservation efforts can be difficult. Determining the rarity of a species is complicated by the plants’ small leaves, which stand only 2-10 centimeters above the soil.[3] Even more of a challenge in obtaining an accurate population count is the genus’s largely subterranean life cycle. The vast majority of any one population of moonworts actually exists below ground in banks consisting of several types of propagules. One type of propagule is the ungerminated spores, which must percolate through the soil beyond the reach of light in order to germinate. This presumably increases the probability that the spore will be in range of a mycorrhizal symbiont before it produces the tiny, roughly heart-shaped gametophyte, which also exists entirely below ground.[7] Finally, some species produce gemmae, a form of asexual propagation achieved by budding of the root.[3]

Juvenile and dormant sporophytes can also be hidden in the soil for long periods of time. Mature sporophytes do not necessarily produce a leaf annually; they can remain viable underground for up to 10 years without putting up a photosynthetic component. This feat is made possible by their dependence on symbiotic partnership with AM fungi of the genus Glomus, which supply most fixed carbon for growth and reproduction.[8]

This mycorrhizal dependence has also made lab cultivation of moonworts difficult. Thus far, only germination of the gametophyte has been successful.


References

  1. ^ Kelly, Dave (1994). "Demography and conservation of Botrychium australe, a peculiar, sparse mycorrhizal fern". New Zealand Journal of Botany 32: 393-400. 
  2. ^ Montgomery, James D. (1990). "Survivorship and Predation Changes in Five Populations of Botrychium dissectum in Eastern Pennsylvania". American Fern Journal. 4 80: 173-182. 
  3. ^ a b c d Johnson-Groh, C. L. and J. Lee (2002). “Phenology and demography of two species of Botrychium (Ophioglassaceae)”. American Journal of Botany 89 (10): 1624-1633.
  4. ^ Wagner, W. H. (1993). Flora of North America. New York: Oxford University Press. pp. 85-91. 
  5. ^ Muller, S. (1992). "The impact of a drought in spring on the sporulation of Botrychium matricariifolium (Retz) A. Br. in the Bitcherland (Northern Vosges, France)". Acta Oecologia 13: 335-343. 
  6. ^ Mesipuu, Meeli; R. P. Shefferson and T. Kull (2009). "Weather and herbivores influence fertility in teh endangered fern Botrychium multifidum (S.G. Gmel.) Rupr". Plant Ecology 203: 23-31. 
  7. ^ Whittier D (1973). “The effect of light and other factors on spore germination in Botrychium dissectum”. Can J Bot 51: 1791-1794.
  8. ^ Winther J, Friedman W (2007). “Arbuscular mycorrhizal symbionts in Botrychium (Ophioglossaceae)”. Am J Bot 94 (7): 1248-1255.

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  • Botrychĭum — Sw. (Mondraute), Gattung der Ophioglossazeen, ausdauernde Farne mit unterirdischem kurzen Stämmchen und einem einzigen Blatt, von dem ein Abschnitt steril und fiederförmig geteilt ist, während der andre rispig verzweigt erscheint und an seinen… …   Meyers Großes Konversations-Lexikon

  • Botrychium — Botrychĭum Sw., Farngattg. der Ophioglosseen, in der nördl. gemäßigten Zone; B. lunarĭa Sw. (Mondraute, Walpurgiskraut [Abb. 253]) in Deutschland häufig …   Kleines Konversations-Lexikon

  • Botrychium — Botryche Le Botr …   Wikipédia en Français

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  • Botrychium, — Rautenfarne Echte Mondraute (Botrychium lunaria) Systematik Unterreich: Gefäßpflanzen (Tracheobionta) …   Deutsch Wikipedia

  • Botrychium Sw. — Род 10. Гроздовник (Сем. Ophioglossaceae – Ужовниковые) 14. Botrychium lunaria Sw. – Гроздовник полулунный 16. Botrychium multifidum Rupr. – Гроздовник многораздельный 17. Botrychium virginianum Sw. – Гроздовник виргински …   Флора Центрально-лесного государственного заповедника

  • Botrychium — ID 10226 Symbol Key BOTRY Common Name grapefern Family Ophioglossaceae Category Fern Division Pteridophyta US Nativity N/A US/NA Plant Yes State Distribution AK, AL, AR, AZ, CA, CO, CT, DC, DE, FL, GA, IA, ID, IL, IN, KS, KY, LA, MA, MD, ME, MI,… …   USDA Plant Characteristics

  • Botrychium — noun grape fern; moonwort • Syn: ↑genus Botrychium • Hypernyms: ↑fern genus • Member Holonyms: ↑Ophioglossaceae, ↑family Ophioglossaceae • Member Meronyms: ↑ …   Useful english dictionary

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