Tylosema

Tylosema
Marama bean
Scientific classification
Kingdom: Plantae
(unranked): Angiosperms
(unranked): Eudicots
(unranked): Rosids
Order: Fabales
Family: Fabaceae
Subfamily: Caesalpinioideae
Tribe: Cercideae[1]
Genus: Tylosema
(Schweinf.) Torre & Hillc.
Type species
Tylosema fassoglensis
(Kotschy ex Schweinf.) Torre & Hillc.
Species

4–5; see text.

The range of Tylosema.

The genus Tylosema is in the plant family Fabaceae and encompasses four accepted species of perennial legume native to southern and central Africa. These are semi-woody viniferous plants broadly distributed from Sudan and Ethiopia south to Angola and South Africa.[2] Coetzer and Ross[3] originally described four Tylosema species:

Species

There are four documented species within the genus Tylosema (Schweinf.) Torre & Hillc.:[4][5][6]

Proposed species:

Common Names

Creeping bauhinia (English), Gwangwandiza (Shona), Marama bean, gemsbok bean, tamani berry (English), Morama bean, gami (Khoi), Mubopo (Shona), Mutukutupasi (Shona), Umbama or Umdabule (Ndebele).[8][9]

Habitat

Habitat for Tylosema species is diverse and particular to each species. T. esculentum is found mostly on sandy plains, while T. fassoglense can be found from open grassland to desert to woodlands to roadsides. All species are found from low to moderate altitude.[7]

Tylosema species grow in mostly sandy soils with low rainfall and can tolerate scorching heat and long-term drought. Typical daily high temperatures average 37 °C during growing season and radiation frequently exceeds 2000 μmol m−2 s−1.[10] Whereas many legumes can fix atmospheric nitrogen, all Tylosema species are non-nodulating.[8]

Vegetation is a climbing vine, with some species reaching up to 6 m long. Herbaceous stems trail or climb, originating from a large underground tuber that is visible above the soil surface. Leaves are simple and 2-lobed. Forked tendrils are usually present. Inflorescence is a lateral raceme. Flowers are yellow, bisexual, heterostylous, with 5 petals. Pods are large, woody and have 1 or 2 seeds.[9] Herostyly, or flower polymorphism, occurs in all species of Tylosema, although it is unknown in the rest of the Leguminosae family.[11]

Phylogeny

Tylosema species are in the Leguminosae family, the third largest family of flowering plants (Doyle and Luckow, 2003), in the subfamily Caesalpinioideae, in the tribe Cercideae. The type species for the Tylosema genus is T. fassoglense.[7]

The phylogeny of Tylosema is somewhat disputed. [12][13][14] This is in part because is has not been widely collected or studied. Although previously located in the Bauhinia genus, now Tylosema has been established as its own genus and is strongly supported as monophyletic.[15]

Wunderlin has proposed a reorganization of the Cercideae tribe wherein 12 genera are placed into two subtribes, Cercinidae and Bauhiniinae. Bauhiniinae is divided into two clades, the first is poorly resolved and includes the genera Bauhinia, Brenierea and Piliostigma. The second clade comprises the genera Tylosema, Barklya, Gigasiphon, Lysiphyllum, Phanera, and Schnella.[16]

Biology and Use

In Botswana and Namibia T. esculentum, or Morama bean, is a staple food of the Khoisan people but plants have not been established for cultivation. The beans have high protein content (30-39%) and high oil content (36-43%)and are eaten after boiling or roasting.[8][17] Beans also have significant levels of calcium, iron, zinc, phosphate, magnesium, and B vitamins including folate.[18]

Preliminary research indicates that seeds of T. esculentum have no physiological dormancy, although germination is improved by scarification.[19] It is disputed as to whether Morama beans exhibit antiviral and antimicrobial properties.[20][21]

Research shows that T. esculentum is both drought avoidant and drought tolerant, but this has not been measured in other Tylosema species.[10][22]

References

  1. ↑ Sinou C, Forest F, Lewis GP, Bruneau A. (2009). "The genus Bauhinia s.l. (Leguminosae): a phylogeny based on the plastid trnL–trnF region". Botany 87 (10): 947–960. doi:10.1139/B09-065.
  2. ↑ Hartley ML, Tshamekeng E, Thomas SM. (2002). "Functional Heterostyly in Tylosema esculentum (Caesalpinioideae)". Ann Bot 89 (1): 67–76. doi:10.1093/aob/mcf006. PMID 12096820.
  3. ↑ Coetzer, L. A., and J. H. Ross. 1977. Tylosema. In Ross, J. H., ed., Fl. Southern Africa 16(2):61-64
  4. ↑ "ILDIS LegumeWeb entry for Tylosema". International Legume Database & Information Service. Cardiff School of Computer Science & Informatics. Retrieved 8 May 2014.
  5. ↑ USDA, ARS, National Genetic Resources Program. "GRIN species records of Tylosema". Germplasm Resources Information Network—(GRIN) [Online Database]. National Germplasm Resources Laboratory, Beltsville, Maryland. Retrieved 5 May 2014.
  6. ↑ "The Plant List entry for Tylosema". The Plant List. Royal Botanic Gardens, Kew and the Missouri Botanical Garden. 2013. Retrieved 5 May 2014.
  7. ↑ 7.0 7.1 7.2 Castro S, Silveira P, Pereira Coutinho A, Figueiredo E. (2005). "Systematic studies in Tylosema (Leguminosae)". Bot J Linn Soc 147 (1): 99–115. doi:10.1111/j.1095-8339.2005.00353.x.
  8. ↑ 8.0 8.1 8.2 Jackson, Jose; Kwaku G. Duodu, Mette Holse, Lima de Faria, Margarida D, Danie Jordaan, Walter Chingwaru, Aase Hansen, Avrelija Cencic, Martha Kandawa-Schultz, and Selalelo M. Mpotokwane. (2010). "The morama bean (Tylosema esculentum): A potential crop for southern Africa.". Advances in Food and Nutrition Research 61 (5): 187-246.
  9. ↑ 9.0 9.1 "Tylosema Torre & Hillc.". Flora of Zimbabwe. Hyde, M.A., Wursten, B.T., Ballings, P. & Coates Palgrave, M. October 12, 2013. Retrieved October 17, 2014.
  10. ↑ 10.0 10.1 Mitchell, RAC; Keys AJ, Madgwick, PJ, Parry MAJ, and DW Lawlor. (2005). "Adaptation of photosynthesis in marama bean - Tylosema esculentum (burchell A. schreiber) to a high temperature, high radiation, drought-prone environment.". Plant Physiology and Biochemistry 43 (10): 969-76.
  11. ↑ Hartley, Mary Luisa; Tshamekeng, Ernest, and Sandy M. Thomas. (2002). "Functional heterostyly in Tylosema esculentum (caesalpinioideae).". Annals of Botany 89 (1): 67-76.
  12. ↑ Lewis, G., Schrire, B., Mackinder, B. & Lock, M. (eds.), (2005). "Tribe Cercideae. Lewis, G. & Forest, F.". Legumes of the World. Kew: Royal Botanic Gardens. pp. pp. 57–67.
  13. ↑ Banks, Hannah, Félix Forest, and Gwilym Lewis. (2014). "Evolution and diversity of pollen morphology in tribe cercideae (leguminosae).". Taxon 63 (2): 299-314.
  14. ↑ Bruneau, Anne, Marjorie Mercure, Gwilym P. Lewis, and Patrick S. Herendeen. (2008). "Phylogenetic patterns and diversification in the caesalpinioid legumes.". Botany 86 (7) (07): 697-718.
  15. ↑ Sinou, Carole, Fé Forest, Gwilym P. Lewis, and Anne Bruneau. (2009). "The genus Bauhinia s.l. (leguminosae): A phylogeny based on the plastid trnL–trnF region.". Botany 87 (10) (10): 947-60.
  16. ↑ Wunderlin, RP (2010). "Reorganization of the Cercideae (Fabaceae: Caesalpinioideae).". Phytoneuron 2010-48: 1–5.
  17. ↑ Taatsu, Kapewangolo Petrina. 2010. Biochemical characteristics of marama bean (Tylosema esculentum). Master's degree thesis. University of Namibia. http://repository.unam.na/handle/11070/473
  18. ↑ Holse; Husted S., and A. Hansen. (2010). "Chemical composition of marama bean (Tylosema esculentum)—A wild African bean with unexploited potential.". Journal of Food Composition & Analysis 23 (6) (09): 648-57.
  19. ↑ Travlos, IS; Economou G, and AI Karamanos. (2007). "Germination and emergence of the hard seed coated Tylosema esculentum (Burch) A. Schreib in response to different pre-sowing seed treatments.". Journal of Arid Environments, 68(3), 501-507.
  20. ↑ Chingwaru, W; Majinda RT, Yeboah SO, Jackson J, Kapewangolo PT, Kandawa-Schulz M, and A Cencic. (2011). "Tylosema esculentum (marama) tuber and bean extracts are strong antiviral agents against rotavirus infection.". Evidence-Based Complementary & Alternative Medicine (eCAM) 8 (1) (01): 1-11.
  21. ↑ Mazimba, O.; Majinda RT, Modibedi C, Masesane IB, Cencič A, and W Chingwaru. (2011). "Tylosema esculentum extractives and their bioactivity.". Bioorganic & Medicinal Chemistry 19 (17): 5225-30.
  22. ↑ Karamanos, AJ; Travlos, IS. (2012). "The water relations and some drought tolerance mechanisms of the marama bean.". Agronomy Journal 104 (1): 65-72.