Our future fruiters
Irvingia gabonensis (Aubry, Lec ex O. Rorke) Baill.
Trait. Med. Phan. 2: 881 (1883)
Synonyms: Irvingia barteri Hook f. Irvingia tenuifolia Hook f. Mangifera gabonensis Aubrey Lecomte ex O'Rorke
Common names: Andok, wild mango. English: bush mango
Local names: Bafo: bope. Bakoko: avia, ndoka. Bakossi: etou. Bakundu: bopala, weke. Bakwéri: bwiwa. Balong: bopek. Bassa: wiba. Batanga: boubwe. Bobili: atelem. Boki: bojep. Boulou: ando'o. Douala: bwiba, bamboo. Ejagham: nsen. Ewondo: andok. Fang: andok. Ibo: obono. Mvaé: ando. Pygmy Bagielli: ntwa. Pygmy Baka: pekie. Vouted: ndok.
Origin, geographical distribution and ecology
Species from tropical Africa, from Sierra Leone to Angola, in low-lying humid forests, especially formerly inhabited areas. It is found everywhere in the forest zone in Cameroon, except in mountain forest.
Tree up to 40 m tall and 120 cm in diameter; hemispherical crown with erect, branching branches, dense foliage, dark green; it was more or less tortuous and more or less cylindrical; base with more or less developed buttresses; bark gray-yellowish, scaly, rather thick slice, granular yellow-brown, brittle.
Leaves alternate, simple; elliptic to obovate-elliptical limb, up to 11 x 6 cm, acuminate apex, slightly asymmetrical base; leathery and shiny on both sides; Sickle-shaped stipules up to 2.5 cm long.
Axillary inflorescences in short racemes of fascicles of 3-5 flowers.
Flowers small, yellow-greenish, hermaphrodites, pentamers; 5 reflected sepals; 5 petals quickly deciduous; 10 stamens inserted under a thick yellow disc; ovary with 2 boxes.
Fruits: drupes yellowverdâtre largely ellipsoid, compressed, about 5-6 cm long; fleshy pulp, very fibrous, yellow; Core with hard, flat integument, weighing about 15 g dry, covered with fibrils.
Single seed, flattened, yellow or red.
Flowering from November to March-June. Fructification from April to July-September.
Variability and conservation of the resource
The genus Irvingia has six species among which I. robur, I. grandifolia, I. wombulu, I. excelsa, I. smithii and Irvingia gabonensis. The center of diversity of the Irvingia genus would be the forests of the Congo Basin. They are found not only in natural forest, but also and especially in coffee plantations, cocoa plantations and in fallow land where they are protected during clearing of crops. In southwestern Cameroon, Irvingia's crop is expanding, driven by strong market demand in neighboring Nigeria. All of these constitute forms of in situ and ex situ conservation of this species. On a formal level, IRAD and ICRAF undertook a survey in 1994 on Irvingiadans in the Congo Basin. This collection mission covered the southern part of Cameroon, Gabon and southern Nigeria. The collected material constitutes the collections of Mbamayo in Cameroon and Onne in Nigeria. The genetic material in these collections consists essentially of 2 species of food value and economic value: Irvingia gabonensis and Irvingia wombulu.
The systematic collection of ripening fruit significantly limits the natural regeneration of the species. The seedlings are however produced in nurseries by sowing seeds.
The species breeds by seed. The seeds are of recalcitrant type, with a maximum germination rate of 95% when freshly picked, mature, non-mutilated and in good sanitary condition. In the nursery, decomposed sawdust is an ideal germination substrate because of its easy-to-use germinating nature.
It shows a good aptitude for the formation of adventitious roots; therefore, it is possible to produce marcot plants on trees with desirable traits. Unfortunately, there is a high mortality after weaning, hence the need for the development of an appropriate postweaning technique.
It is a forest species and its young plants do not support, both in nursery and field, a direct and prolonged sunshine. They grow best when they are slightly shaded.
Recommended planting distances are 10 m between rows and 8 m between plants on the line. The age of entry into production of the plants is 6 to 10 years.
The spread is made by large mammals, including elephants. As for the pollination, it is ensured essentially by the Hymenoptera (bees). Direct seeding of kernels has an exceptional emergence (95%). The seeds of I. gabonensis should be sown as fresh as possible immediately after pulping. If they are forced to keep them, the maximum shelf life should not exceed 10 days, at which time the exercise rate is 22%. This shows that these seeds belong to the category of so-called recalcitrant seeds, which do not support dehydration. Propagation is also by cuttings and marcots. Fruiting in the forest is late (10-15 years). In plantation, when the plants are well maintained, this duration can be reduced by half. Uses The parts used are: fruits, seeds, leaves, bark, hull and wood. Irvingia gabonensis is considered a lucky charm. For this, the tree is left in the fields of food crops and its bark is used as a talisman to give or return fertility to the ground. The shell of the fruit is also a talisman that is carried to small children to ensure their good health. The almond contained in the seed is oleaginous and edible (Vivien and Faure, 1995). Crushed seeds form a loaf called "Etsim or chocolate" in the "Fang" and "Bulu" communities of Cameroon, or "Dika bread" in Gabon. Crushed almonds give a paste used to thicken and flavor sauces. The dough can be stored long after sun drying and a thick oil can be extracted hot (Vivien and Faure 1995, Walker and Sillans 1995). The pulp, rich in vitamin C, can be sucked to quench thirst. In traditional pharmacopoeia, almond paste with astringent properties can be applied to burns. Grated bark, used as an enema, or simply eaten with plantain, is used to treat diarrhea and dysentery (Walker and Sillans, 1995). The wood is used in construction for large frames. It is also used for the manufacture of mortars, pestles etc.