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gnetum

{{Short description|Genus of gymnosperms in family Gnetaceae}}

{{Use mdy dates|date=October 2024}}

{{Automatic taxobox

| image = Gnetum luofuense 125787614.jpg

| image_caption = Gnetum luofuense in China

| grandparent_authority = Mart

| parent_authority = Blume

| taxon = Gnetum

| authority = L.

| type_species = Gnetum gnemon

| type_species_authority = L.

| synonyms_ref = [http://apps.kew.org/wcsp/namedetail.do?name_id=334088 Kew World Checklist of Selected Plant Families]

|synonyms =

  • Gnemon Rumph. ex Kuntze
  • Thoa Aubl.
  • Abutua Lour.
  • Arthostema Neck.

| range_map = Gnetum distribution.PNG

| range_map_alt = Map showing the range of Gnetum

| range_map_caption = Distribution

}}

Gnetum is a genus of gymnosperms, the sole genus in the family Gnetaceae within the Gnetophyta. They are tropical evergreen trees, shrubs and lianas. Unlike other gymnosperms, they possess vessel elements in the xylem. Some species have been proposed to have been the first plants to be insect-pollinated as their fossils occur in association with extinct pollinating scorpionflies.{{Cite journal |doi=10.1126/science.1178338 |title=A Probable Pollination Mode Before Angiosperms: Eurasian, Long-Proboscid Scorpionflies |date=2009 |last1=Ren |first1=Dong |last2=Labandeira |first2=Conrad C. |last3=Santiago-Blay |first3=Jorge A. |last4=Rasnitsyn |first4=Alexandr |last5=Shih |first5=Chungkun |last6=Bashkuev |first6=Alexei |last7=Logan |first7=M. Amelia V. |last8=Hotton |first8=Carol L. |last9=Dilcher |first9=David |journal=Science |volume=326 |issue=5954 |pages=840–847 |pmid=19892981 |pmc=2944650 |bibcode=2009Sci...326..840R }} Molecular phylogenies based on nuclear and plastid sequences from most of the species indicate hybridization among some of the Southeast Asian species. Fossil-calibrated molecular-clocks suggest that the Gnetum lineages now found in Africa, South America and Southeast Asia are the result of ancient long-distance dispersal across seawater.{{Cite journal |doi=10.1016/j.ympev.2005.03.011 |title=The internal transcribed spacer of nuclear ribosomal DNA in the gymnosperm Gnetum |date=2005 |last1=Won |first1=Hyosig |last2=Renner |first2=Susanne S. |journal=Molecular Phylogenetics and Evolution |volume=36 |issue=3 |pages=581–597 |pmid=16099382 |bibcode=2005MolPE..36..581W }}{{Cite journal |doi=10.1080/10635150600812619 |title=Dating Dispersal and Radiation in the Gymnosperm Gnetum (Gnetales)—Clock Calibration when Outgroup Relationships Are Uncertain |date=2006 |last1=Won |first1=Hyosig |last2=Renner |first2=Susanne S. |journal=Systematic Biology |volume=55 |issue=4 |pages=610–622 |pmid=16969937 }}

Their leaves are rich in phytochemicals such as flavonoids and stilbenes. Of the species studied so far, Gnetum have photosynthetic and transpiration capacities which are considerably lower than those of other seed plants, due to the absence of multiple chloroplast genes essential for photosynthesis, a trait they seem to share with the other living members of Gnetophyta, Ephedra and Welwitschia, as well as conifers.{{cite journal | pmc=6370715 | date=2019 | last1=Deng | first1=N. | last2=Hou | first2=C. | last3=Liu | first3=C. | last4=Li | first4=M. | last5=Bartish | first5=I. | last6=Tian | first6=Y. | last7=Chen | first7=W. | last8=Du | first8=C. | last9=Jiang | first9=Z. | last10=Shi | first10=S. | title=Significance of Photosynthetic Characters in the Evolution of Asian Gnetum (Gnetales) | journal=Frontiers in Plant Science | volume=10 | page=39 | doi=10.3389/fpls.2019.00039 | doi-access=free | pmid=30804953 }} There are over 50 different species of Gnetum.{{citation needed|date=April 2022}}

Species

{{cladogram|title=Phylogeny of Gnetum{{cite journal |first1=Chen |last1=Hou |first2=Aelys M. |last2=Humphreys |first3=Olle |last3=Thureborn |first4=Catarina |last4=Rydin |date=April 2015 |title=New insights into the evolutionary history of Gnetum (Gnetales) |journal=Taxon |volume=64 |issue=2 |pages=239–253 |url=http://dx.doi.org/10.12705/642.12 |doi=10.12705/642.12|url-access=subscription }}|

{{clade|style=font-size:90%;line-height:100%;width:350px

|1={{clade

|1=subsection Araeognemones

|2={{clade

|1=subsection Micrognemones

|2={{clade

|1=section Gnetum

|label2=section Scandentia

|2={{clade

|1=subsection Gnemonoides

|2={{clade

|1=subsection Stipitati

|2=subsection Sessiles

}}

}}

}}

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{{cladogram|title=Phylogeny of Gnetum{{cite journal |last1=Stull |first1=Gregory W. |last2=Qu |first2=Xiao-Jian |last3=Parins-Fukuchi |first3=Caroline |last4=Yang |first4=Ying-Ying |last5=Yang |first5=Jun-Bo |last6=Yang |first6=Zhi-Yun |last7=Hu |first7=Yi |last8=Ma |first8=Hong |last9=Soltis |first9=Pamela S. |last10=Soltis |first10=Douglas E. |last11=Li |first11=De-Zhu |last12=Smith |first12=Stephen A. |last13=Yi |first13=Ting-Shuang |display-authors=et al. |year=2021 |title=Gene duplications and phylogenomic conflict underlie major pulses of phenotypic evolution in gymnosperms |journal=Nature Plants |url=https://www.nature.com/articles/s41477-021-00964-4 |volume=7 |issue= 8|pages=1015–1025 |doi=10.1038/s41477-021-00964-4|biorxiv=10.1101/2021.03.13.435279 |pmid= 34282286|s2cid=232282918 |doi-access=}}{{cite journal |last1=Stull |first1=Gregory W. |display-authors=et al. |year=2021 |title=main.dated.supermatrix.tree.T9.tre |journal=Figshare |doi=10.6084/m9.figshare.14547354.v1 |url=https://figshare.com/articles/dataset/Gene_duplications_and_genomic_conflict_underlie_major_pulses_of_phenotypic_evolution_in_gymnosperms/14547354 |doi-access=}}|

{{clade|style=font-size:90%;line-height:100%;width:450px

|1={{clade

|1={{clade

|label1=section

|sublabel1=Micrognemones

|1=G. buchholzianum Engler

}}

|2={{clade

|1={{clade

|1=G. africanum (de Loureiro) Welwitsch

|2={{clade

|label1=section

|sublabel1=Gnetum

|1={{clade

|1={{clade

|label1=subsection

|sublabel1=Gnetum

|1={{clade

|1=G. costatum Schum.

|2=G. gnemon von Linné

}}

}}

|2={{clade

|label1=subsection

|sublabel1=Gnemonoides

|1={{clade

|1=G. raya Markgraf

|2=G. gnemonoides Brongniart

}}

|label2=subsection

|sublabel2=Araeognemones

|2={{clade

|1={{clade

|1=G. leyboldii Tulasne

|2=G. nodiflorum Brongniart

}}

|2={{clade

|1=G. schwackeanum Taubert & Schenck ex Taubert & Markgraf

|2={{clade

|1=G. paniculatum Spruce ex Bentham

|2={{clade

|1=G. camporum (Markgraf) Stevenson & Zanoni

|2=G. urens (Aublet) Blume

}}

}}

}}

}}

}}

}}

}}

}}

|2={{clade

|label1=section

|sublabel1=Scandentia

|1={{clade

|1={{clade

|1=G. microcarpum Blume

|2={{clade

|1=G. diminutum Markgraf

|2=G. klossii Merrill ex Markgraf

}}

}}

|2={{clade

|label1=subsection

|sublabel1=Stipitati

|1={{clade

|1=G. parvifolium (Warburg) Cheng

|2={{clade

|1=G. luofuense Cheng

|2={{clade

|1=G. indicum (de Loureiro) Merrill

|2={{clade

|1=G. hainanense Cheng ex Fu, Yu & Gilbert

|2=G. montanum Markgraf

}}

}}

}}

}}

|label2=subsection

|sublabel2=Sessiles

|2={{clade

|1=G. macrostachyum Hooker

|2={{clade

|1=G. latifolium Blume

|2={{clade

|1=G. edule (Willdenow) Blume

|2={{clade

|1={{clade

|1=G. neglectum Blume

|2=G. leptostachyum Blume

}}

|2={{clade

|1=G. ula Brongniart

|2={{clade

|1=G. tenuifolium Ridley

|2=G. cuspidatum Blume

}}

}}

}}

}}

}}

}}

}}

}}

}}

}}

}}

}}

}}

There are around 50 different species of Gnetum. The Catalogue of Life lists 44 species.{{r|col}}

Uses

Many Gnetum species are edible, with the seeds being roasted, and the foliage used as a leaf vegetable.Hoe, V.B. and Siong, K.H., "The Nutritional Value of Indigenous Fruits and Vegetables in Sarawak,"Asia-Pacific Journal of Clinical Nutrition, Vol. 8, no. 1, 1998, pp 24-31 The plant is harvested and yields a useful fiber.{{clarify|reason=Dietary or fabric?|date=April 2022}} There is no sense of danger in consuming the fruit or the seeds.{{Cite web |title=Gnetum gnemon {{!}} plant {{!}} Britannica |url=https://www.britannica.com/plant/Gnetum-gnemon |access-date=May 2, 2022 |website=Encyclopædia Britannica}}

There is also a study done on the plant to see if it has any medicinal properties, finding some anti-coagulation effects due to its stilbenoid content. The family Gnetaceae is well known as a rich source of plant-derived stilbenoids as well as Cyperaceae, Dipterocarpaceae, Fabaceae, and Vitaceae.{{Cite journal |title=Stilbenoids from Gnetum macrostachyum Attenuate Human Platelet Aggregation and Adhesion |url=https://www.researchgate.net/publication/224284860 |journal= Phytotherapy Research|year=2012|doi=10.1002/ptr.4605|last1=Kloypan |first1=Chiraphat |last2=Jeenapongsa |first2=Rattima |last3=Sri-In |first3=Piyawit |last4=Chanta |first4=Surin |last5=Dokpuang |first5=Dech |last6=Tip-Pyang |first6=Santi |last7=Surapinit |first7=Nattanan |volume=26 |issue=10 |pages=1564–1568 |pmid=22511550 |s2cid=43249684 }}

Conservation

Some species of Gnetum are in danger of dying out. The habitats are being removed with the trees being cut down to create industry. The tropical rainforest are being destroyed so many of the species are going extinct such as Gnetum oxycarpum. The rainforests are being torn down and being turned into farmland. Gnetum live in only a small part of the rainforest.

Gallery

File:倪藤果 Gnetum gnemon -檳城熱帶果園 Tropical Fruit Farm, Penang- (9222653200).jpg|Gnetum gnemon carpellate/female cones

File:Gnetum latifolium - കറുത്ത ഓടൽ.jpg|Gnetum latifolium staminate/male cones

File:Gnetum africanum Leaves (Eru, Okok).jpg|Gathered leaves of Gnetum africanum

File:Gnetum gnemon seeds, by Omar Hoftun.jpg|Gnetum gnemon seeds

References

{{Reflist|refs=8. Gnetum macrostachyum - Useful Tropical Plants, https://tropical.theferns.info/viewtropical.php?id=Gnetum%2Bmacrostachyum.

9. Catalogue of life: 2010 annual checklist. Catalogue of Life - 2010 Annual Checklist :: Species details. (n.d.). Retrieved December 23, 2021, from http://www.catalogueoflife.org/annual-checklist/2010/details/species/id/7279121

10.The IUCN Red List of Threatened Species. IUCN Red List of Threatened Species. (n.d.). Retrieved December 23, 2021, from https://www.iucnredlist.org/

{{cite web

|access-date=October 24, 2024

|title=Gnetum L.

|url=https://www.catalogueoflife.org/data/taxon/8VXX3

|website=Catalogue of Life

}}

}}

External links

{{Commons category|Gnetum}}

  • [http://www.conifers.org/gn/index.htm Gymnosperm Database - Gnetum]
  • [http://www.plantnames.unimelb.edu.au/Sorting/Gnetum.html Sorting Gnetum names]
  • [http://www.fao.org/docrep/X2161E/x2161e06.htm Uses of Gnetum in Africa (FAO)] {{Webarchive|url=https://web.archive.org/web/20190111234159/http://www.fao.org/docrep/X2161E/x2161e06.htm |date=January 11, 2019 }}
  • Kloypan, Chiraphat & Jeenapongsa, Rattima & Sri-In, Piyawit & Chanta, Surin & Dokpuang, Dech & Tip-Pyang, Santi & Surapinit, Serm. (2012). Stilbenoids from Gnetum macrostachyum Attenuate Human Platelet Aggregation and Adhesion. Phytotherapy research : PTR. 26. 1564–8. 10.1002/ptr.4605.
  • https://bsapubs.onlinelibrary.wiley.com/doi/abs/10.1002/j.1537-2197.1916.tb05408.x {{Webarchive|url=https://web.archive.org/web/20211222040854/https://bsapubs.onlinelibrary.wiley.com/doi/abs/10.1002/j.1537-2197.1916.tb05408.x |date=December 22, 2021 }}
  • http://www.theplantlist.org/tpl1.1/record/kew-334161...

{{WestAfricanPlants|Gnetum}}

{{Plant classification}}

{{Acrogymnospermae classification}}

{{Taxonbar|from=Q131550}}

{{Authority control}}

Category:Gnetaceae

Category:Medicinal plants

Category:Dioecious plants

Category:Gymnosperm genera