Prota 14: Vegetable oils/Oléagineux
Matières Grasses 1308 (1909).
Bombacaceae (APG: Malvaceae)
2n = 72, 88
Adansonia fony Baill. ex H.Perrier (1952).
Fony baobab (En). Baobab de Madagascar, petit baobab de Madagascar (Fr).
Origin and geographic distribution
Adansonia rubrostipa is endemic to Madagascar, where it is found along the west coast from Itampolo in the south to Soalala in the north.
The tree is used only occasionally. The fruits, oil-rich seeds and roots are edible, and fruits are sometimes sold in the local market. Sheets of wood of trees killed by fire are dried and used as thatch. A popular edible fungus grows on the trunks of dead trees.
Seed oil content is 11%. The fatty acid composition of the oil is: palmitic acid 30%, stearic acid 2%, oleic acid 30% and linoleic acid 23%. In addition, the oil contains the rare fatty acids malvalic acid 5%, sterculic acid 2%, and dihydrosterculic acid 3%.
Small to medium-sized tree up to 20 m tall; bole cylindrical or bottle-shaped, with distinct constrictions beneath the branches; outer bark usually reddish brown, exfoliating; crown irregular; branches horizontal, erect distally. Leaves arranged spirally, palmately compound, with 3–5 leaflets; stipules caducous; petiole thin and tapering, 3–7 cm long, glabrous; leaflets sessile, elliptical, medial one 4–6(–8) cm × 1–2 cm, margins toothed. Flowers solitary in leaf axils at end of branches, bisexual, regular, 5-merous, large, showy and fragrant; flower bud horizontal, cylindrical, 16–28 cm long; pedicel 1–2.5 cm long, green; calyx with short tube, lobes linear, 15–25 cm × 7–12 mm, reflexed and tightly twisted at base, almost glabrous, yellowish green with faint reddish stripes outside, bright red and sparsely hairy inside; petals free, linear with broadened, overlapping bases, 12–16 cm × 1.5–2.5 cm, bright yellow to orange-yellow; stamens numerous, longer than corolla, fused into a cylindrical tube 6–10 cm long; ovary superior, broadly rounded-conical, c. 7.5 mm long, golden hairy, style 20–25 cm long, pink, hairy at base, fitting tightly in staminal tube, stigma with 5–8 irregular, spreading lobes, red, blackening with age. Fruit a large, globose berry with woody, 4–5 mm thick wall, densely reddish brown hairy, many-seeded. Seeds kidney-shaped, laterally flattened, up to 16 mm × 12 mm × 8 mm. Seedling with hypogeal germination.
The tree is in leaf from November to April and flowers from February to April, rarely up to June. Fruit ripens in October–November.
Adansonia comprises 8 species, of which 6 are endemic to Madagascar, 1 occurs in continental Africa and is introduced in Madagascar, and 1 is endemic to Australia. Adansonia rubrostipa has been classified in the section Longitubae, together with Adansonia gibbosa (A.Cunn.) Guymer ex D.A.Baum from Australia and 2 species from Madagascar : Adansonia madagascariensis Baill. and Adansonia za Baill. Unique characters of Adansonia rubrostipa are leaflets with toothed margins and a central bundle of filaments fused beyond the top of the staminal tube.
Adansonia rubrostipa is a locally dominant tree species in the deciduous forests of western Madagascar. It occurs in spiny and dry forest and in sublittoral scrub, up to 500 m altitude. It normally grows on well-drained calcareous soils and limestone.
Germination can be erratic, either occurring quickly with a good germination rate, or taking longer with a poorer rate. Germination depends on the temperature and humidity of the soil, and on other parameters which are not well understood. Adansonia rubrostipa is fairly resistant to insect pests that attack other Adansonia spp. Fruits are collected by climbing the trees with the aid of wooden pegs hammered into the trunk.
Genetic resources and breeding
In the IUCN Red List of Threatened Species Adansonia rubrostipa is classified as a ‘near threatened’ species that is close to being classified as ‘vulnerable’ in the wild. The main threats come from continuing deforestation. The populations to the north of Toliara are especially at risk.
The fruits and seeds of Adansonia rubrostipa are likely to remain of little importance. Felling of the trees should be discouraged to ensure the survival of the species.
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Correct citation of this article:
Ambrose-Oji, B. & Mughogho, N., 2007. Adansonia rubrostipa Jum. & H.Perrier In: van der Vossen, H.A.M. & Mkamilo, G.S. (Editors). PROTA 14: Vegetable oils/Oléagineux. [CD-Rom]. PROTA, Wageningen, Netherlands.