Canavalia cathartica, commonly known as maunaloa in the Hawaiian language,[1][2][3][4] is a species of flowering plant in the legume family, Fabaceae. The Hawaiian name translates as long mountain.[5] In English it may also be known as poisonous sea bean,[6] ground jack bean, horse bean, silky sea bean or wild bean.[1] It has a Paleotropical distribution,[2] occurring throughout tropical regions in Asia, Africa, Australia, and many Pacific Islands, and extending just into subtropical areas.[7] It is not native to Hawaii, and is an invasive species there.[8]

Canavalia cathartica
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Rosids
Order: Fabales
Family: Fabaceae
Subfamily: Faboideae
Genus: Canavalia
Species:
C. cathartica
Binomial name
Canavalia cathartica
Synonyms

Canavalia glandifolia
Canavalia microcarpa
Canavalia polystachya
Canavalia turgida
Canavalia virosa
Dolichos virosus
Lablab microcarpus
Phaseolus virosus

Description edit

This plant is a biennial[9] or perennial[2] herb with thick, twining, climbing stems. The pinnate leaves are each divided into three papery leaflets which are generally oval in shape with pointed or rounded tips. They are up to 20 centimeters long by 14 wide, but usually smaller. The inflorescence is a raceme[9] or pseudoraceme[2] of several flowers. The flower has a bell-shaped calyx of sepals with two lips, an upper lip with two lobes and a lower lip with three teeth. The flower corolla is pink or purplish[9] with a white-spotted standard petal and two wing and two keel petals each roughly 3 centimeters long.[2] The fruit is an inflated, turgid legume pod up to 13.5 centimeters long by 4.5 wide.[2][9] The fresh, mature pod can weigh over 32 grams.[10] The hard, smooth seeds are reddish brown, darkening deeper brown, and reaching nearly 2 centimeters long by one wide.[2][9]

Ecology edit

In India this plant grows in mangroves. The seeds float on the water and land on coastal sand dunes, where the plant establishes. It is mat-forming and binds the sand, preventing erosion.[10]

This legume has a rich microbial ecology, including its nodal rhizobia, its arbuscular mycorrhizae, and an assemblage of endophytic fungi.[10] Common arbuscular fungal associates include the glomeromycetes Gigaspora albida, Acaulospora spinosa, and several species of Glomus, including G. aggregatum.[10] Microbial surveys have catalogued many endophytes in the plant, with varying assemblages in different habitat types. It houses the ascomycete Chaetomium globosum in its roots.[10] It also contains Colletotrichum dematium,[10] Aspergillus niger, A. flavus, Fusarium oxysporum, and Penicillium chrysogenum.[4] The microbial life hosted by the plant likely helps it persist in harsh coastal habitat.[10]

Uses edit

The seeds and pods are used as famine foods in coastal India.[10][11] It is considered to be an underutilized wild plant with the potential to serve as a protein- and carbohydrate-rich food crop.[10] It has more protein than several other edible legumes such as pigeon pea, chickpea, and cowpea.[11] It grows rapidly, tolerates challenging habitat types such as dry, sandy, saline soils, and appears to be fairly pest-resistant.[10]

Like many legumes, C. cathartica contains antinutrients and requires some processing or preparation before it can be used for food. Antinutrients in the species include phenols, tannins, and lectins such as phytohaemagglutinin.[11] Pressure cooking can reduce antinutrients.[11] Roasting is somewhat less effective.[12]

In small-scale agriculture, farmers use this plant as green manure and mulch and host it in their fields for its nitrogen fixation. It grows easily on farmland in mangrove wetlands, it native habitat.[4] It is used as cattle fodder.[11] The stems with pods and leaves are fed to rabbits and hares.[10][11]

In numerous recent studies from India it is claimed that this species is the wild ancestor of Canavalia gladiata, referencing the 1974 third or paperback edition or the 1968 hardback edition of Tropical Crops: Dicotyledons by J. W. Purseglove,[10] where it mentions that C. virosa may be the ancestor of C. gladiata,[13] however this is likely in error, as with C. virosa in 1968 or 1974 one meant the modern C. africana using the then current taxonomy.[14][15][16] Sauer himself proposed C. gladiolata as the ancestor of C. gladiata in the afore-mentioned article.[14]

The plant grows in Micronesia, where the island inhabitants use it as an herbal remedy for conditions such as cough.[17]

In Hawaii, where it is a non-native and invasive species, its showy flowers and large seeds are used in leis.[18]

References edit

  1. ^ a b Quattrocchi, Umberto; 2012; CRC World Dictionary of Medicinal and Poisonous Plants: Common Names, Scientific Names, Eponyms, Synonyms, and Etymology; Vol.1; Page 773; CRC Press; ISBN 9781420080445; https://books.google.nl/books?id=-37OBQAAQBAJ&pg=PA773&lpg=PA773&dq=Poisonous+sea+bean+canavalia&source=bl&ots=8hGDup1lY_&sig=9dguWluPq0n4NJFDw0DdqzLmH1I&hl=en&sa=X&redir_esc=y
  2. ^ a b c d e f g Canavalia cathartica. Flora of the Hawaiian Islands. Smithsonian National Museum of Natural History.
  3. ^ Canavalia cathartica. Integrated Taxonomic Information System (ITIS).
  4. ^ a b c Anita, D. D. and K. R. Sridhar. (2009). Assemblage and diversity of fungi associated with mangrove wild legume Canavalia cathartica. Tropical and Subtropical Agroecosystems 10(2), 225-35.
  5. ^ en.wiktionary.org https://en.wiktionary.org/wiki/loa;. Retrieved 14 October 2017. {{cite web}}: Missing or empty |title= (help)[title missing]
  6. ^ "Poisonous sea bean (Canavalia cathartica) on the Shores of Singapore". www.wildsingapore.com. Retrieved 14 October 2017.
  7. ^ "Canavalia cathartica". Germplasm Resources Information Network. Agricultural Research Service, United States Department of Agriculture. Retrieved 21 January 2018.
  8. ^ "Maunaloa, Canavalia cathartica Fabales: Fabaceae (Leguminosae)". www.invasive.org. Retrieved 14 October 2017.
  9. ^ a b c d e Canavalia cathartica. Flora of China.
  10. ^ a b c d e f g h i j k l Seena, S. and K. R. Sridhar. (2006). Nutritional and microbiological features of little known legumes, Canavalia cathartica Thouars and C. maritima Thouars of the southwest coast of India. Current Science 90(12), 1638-50.
  11. ^ a b c d e f Bhagya, B., et al. (2006). Biochemical and protein quality evaluation of tender pods of wild legume Canavalia cathartica of coastal sand dunes. Livestock Research for Rural Development 18, 1-20.
  12. ^ Seena, S., et al. (2006). Effect of roasting and pressure-cooking on nutritional and protein quality of seeds of mangrove legume Canavalia cathartica from southwest coast of India. Archived 2016-03-04 at the Wayback Machine Journal of Food Composition and Analysis 19(4), 284-93.
  13. ^ Purseglove, J.W.; 1974; Tropical Crops : Dicotyledons (3rd ed.), pp.242-246; Longman; London; ISBN 978-0470702512
  14. ^ a b Sauer, Jonathan D.; 1964; Revision of Canavalia; Brittonia, Vol. 16, Issue 2, pp.106-181; NYBG Press; New York; accessed at https://documentslide.com/documents/revision-of-canavalia.html
  15. ^ Verdcourt, Bernard; 1971; Flora of Tropical East Africa, Leguminosae (4), Papilionoideae, pp.573-574
  16. ^ Verdcourt, Bernard; 1987; Three Corrections to the Flora of Tropical East Africa; Kew Bulletin, Vol. 42, No. 3; pp.658-660; Springer; Dordrecht; accessed at https://docslide.com.br/documents/three-corrections-to-the-flora-of-tropical-east-africa.html
  17. ^ Canavalia cathartica – Fabaceae. Archived 2013-08-29 at archive.today People and Plants of Micronesia. University of Hawaiʻi at Mānoa.
  18. ^ Barboza, R. Climbing vine makes for beautiful lei. Honolulu Star-Bulletin 13(81) March 21, 2008.