Prota 2: Vegetables/Légumes
2n = 26
Sesame of the gazelle, sesamum (En). Sésame de gazelle (Fr).
Origin and geographic distribution
Sesamum alatum is widely distributed in tropical Africa, occurring in dry regions from Senegal to South Africa. In Madagascar, India and occasionally elsewhere it has been introduced. It is sometimes cultivated around villages.
The leaves and young shoots of Sesamum alatum are collected from the wild and used as a cooked vegetable, sometimes flavoured with its pounded seeds. The seeds are occasionally cooked separately as a relish or boiled with pumpkin leaves and served with a staple food. The seed produces an edible oil, and is used as an aphrodisiac and to cure diarrhoea and other intestinal disorders. A decoction of the leaves is given to cattle to promote their fertility.
There is no information on the nutritional composition of Sesamum alatum leaves, but it is probably comparable to that of Sesamum indicum L. (cultivated sesame) leaves, which is per 100 g edible portion: water 85.5 g, energy 188 kJ (45 kcal), protein 3.4 g, fat 0.7 g, carbohydrate 8.6 g, fibre 2.4 g, Ca 77 mg, P 203 mg, riboflavin 0.3 mg. The nutritional composition of dried seeds per 100 g is: water 7.9 g, energy 1733 kJ (414 kcal), protein 10.8 g, fat 18.1 g, carbohydrate (including fibre) 55.2 g, fibre 30.5 g, Ca 432 mg, P 221 mg (Leung, W.-T.W., Busson, F. & Jardin, C., 1968).
The seed oil has about 5% unsaponifiable matter, consisting of lignans (2-episesalatin 1.4%, sesamin 0.01%, sesamolin 0.01%), sterols (22%) and tocopherols (210–320 mg/kg oil).
Erect annual herb up to 1.5 m tall, with simple or sparsely branched stem, glabrous but with mucilage glands. Leaves opposite, lower ones palmately divided or lobed, upper ones simple; stipules absent; petiole 1–7 cm long; leaflets or lobes of lower leaves lanceolate, central one longest, up to 8 cm × 2 cm, often with undulate margin, blade of upper leaves linear to lanceolate, 3–10 cm long. Flowers solitary in leaf axils, bisexual, zygomorphic, 5-merous; pedicel short, with a nectary at base; calyx campanulate with narrowly triangular lobes c. 3 mm long, densely glandular, deciduous; corolla obliquely campanulate, 2–3 cm long, slightly 2-lipped, pink or purple, inside sometimes red-spotted, pubescent; stamens 4; disk fleshy, conspicuous; ovary superior, hairy, 2-celled, style filiform, stigma 2-lobed. Fruit a narrowly obconical capsule up to 5 cm × 0.7 cm, base gradually narrowed, apex with beak up to 12 mm long, 4-grooved, dehiscing longitudinally, many-seeded. Seeds obconical, c. 2.5 mm × 1.5 mm, with a large, 2–3 mm long wing at apex and 2 shorter wings at base, testa with honeycomb-like structure, pale to dark brown.
Sesamum comprises about 20 species, most of which are indigenous to tropical Africa. Sesamum alatum belongs to section Sesamopteris, together with Sesamum triphyllum Welw. ex Asch., both species having winged seed.
Sesamum alatum occurs in dry savanna and is often common around villages, sometimes tolerated as a weed in fields. It is often found on sandy soils, in river beds, grassland and open bushland, or as a weed in fields, often in cultivated sesame.
Genetic resources and breeding
Sesamum alatum is widespread and not in danger of genetic erosion. It has been suggested that Sesamum alatum is one of the progenitors of the cultivated sesame (Sesamum indicum). Crosses of Sesamum alatum and Sesamum indicum have given fertile hybrids that may be important in breeding programmes for improved sesame cultivars. For example, attempts have been made to transfer the resistance of Sesamum alatum to the phyllody disease (a highly destructive phytoplasma disease of sesame transmitted by a leafhopper) to sesame cultivars. Sesamum alatum also proved to be highly resistant to sesame leaf roller and pod borer.
Sesamum alatum will remain a minor vegetable of local importance in drier areas. It may play an important role in breeding programmes of sesame.
• Bedigian, D. & van der Maesen, J., 2003. Slimy leaves and oily seeds: distribution and use of Sesamum spp. and Ceratotheca sesamoides (Pedaliaceae) in Africa. In: Schmelzer, G.H. & Omino, E.A. (Editors). Proceedings of the First PROTA International Workshop 23–25 September 2002, Nairobi, Kenya. Plant Resources of Tropical Africa (PROTA) Foundation, Wageningen, Netherlands. pp. 271–274.
• Burkill, H.M., 1997. The useful plants of West Tropical Africa. 2nd Edition. Volume 4, Families M–R. Royal Botanic Gardens, Kew, United Kingdom. 969 pp.
• Busson, F., 1965. Plantes alimentaires de l’ouest Africain: étude botanique, biologique et chimique. Leconte, Marseille, France. 568 pp.
• Ihlenfeldt, H.-D., 1988. Pedaliaceae. In: Launert, E. (Editor). Flora Zambesiaca. Volume 8, part 3. Flora Zambesiaca Managing Committee, London, United Kingdom. pp. 86–113.
• Baskaran, R.K.M., Mahadevan, N.R., Sridhar, P., Kandasamy, G. & Thangavelu, S., 1990. In vivo and in vitro screening of germplasm against sesame leaf roller and pod borer. Journal of Oilseeds Research 7(1): 36–41.
• Bruce, E.A., 1953. Pedaliaceae. In: Turrill, W.B. & Milne-Redhead, E. (Editors). Flora of Tropical East Africa. Crown Agents for Oversea Governments and Administrations, London, United Kingdom. 23 pp.
• Humbert, H., 1971. Pédaliacées (Pedaliaceae). Flore de Madagascar et des Comores, familles 179–180. Muséum National d’Histoire Naturelle, Paris, France. pp. 5–46.
• Kamal-Eldin, A. & Appelqvist, L.A., 1994. Variations in the composition of sterols, tocopherols and lignans in seed oils from four Sesamum species. Journal of the American Oil Chemists’ Society 71(2): 149–156.
• Leung, W.-T.W., Busson, F. & Jardin, C., 1968. Food composition table for use in Africa. FAO, Rome, Italy. 306 pp.
• Parani, M., Singh, K.N., Rangasamy, S.R.S. & Ramalingam, R.S., 1996. A study on mechanism of phyllody disease resistance in Sesamum alatum Thonn. Current Science 70(1): 86–89.
• Reddy, A.R. & Das, V.S.R, 1995. Characteristics of high efficiency photosynthesis in Sesamum alatum Thonn., a C3 species. Acta Physiologiae Plantarum 17(3): 249–254.
• Smartt, J. & Simmonds, N.W. (Editors), 1995. Evolution of crop plants. 2nd Edition. Longman, London, United Kingdom. 531 pp.
• Tredgold, M.H., 1986. Food plants of Zimbabwe. Mambo Press, Gweru, Zimbabwe.153 pp.
Correct citation of this article:
Jansen, P.C.M., 2004. Sesamum alatum Thonn. ex Schumach. In: Grubben, G.J.H. & Denton, O.A. (Editors). PROTA 2: Vegetables/Légumes. [CD-Rom]. PROTA, Wageningen, Netherlands.