Prota 2: Vegetables/Légumes
Esquisse fl. Tristan d’Acugna: 35 (1808).
2n = 82
Asplenium proliferum Lam. (1786), Callipteris prolifera (Lam.) Bory (1804), Diplazium accedens Blume (1828), Callipteris accedens (Blume) J.Sm. (1841), Athyrium accedens (Blume) Milde (1870).
Mother fern (En).
Origin and geographic distribution
Diplazium proliferum is widespread in tropical Africa, from Guinea to Cameroon and Equatorial Guinea (Bioko), São Tomé et Principe, DR Congo and Madagascar.
In Madagascar the young still enrolled fronds (croziers, fiddleheads) are eaten as a cooked vegetable. In South-East Asia the croziers as well as the bulbils present on the rachis are eaten boiled or steamed as a vegetable, or raw as a salad. Diplazium proliferum is widely planted as an ornamental.
The related Diplazium esculentum (Retz.) Sw. is the most important fern used for human food in the world. It does not occur in Africa.
Large fern with erect rhizome covered with brown scales at apex. Leaves slightly leathery, clustered at apex of rhizome, producing bulbils and young plants all over the rachis; petiole 3–60 cm long, straw-coloured; lamina 60–200 cm long, pinnate; pinnae numerous, lanceolate, the lower ones slightly reduced, median pinnae alternate, 6–7 cm apart, shortly petiolate, 15–20 cm × 3–5 cm, truncate at base, apex abruptly narrowed into a long tip; lobes of pinnae rounded or emarginate at apex, denticulate; bases of pinnae proliferous, with young plantlets on the upper side. Sori linear, in a characteristic V-shaped arrangement following all veinlets of the lobes, usually 4–5, but up to 7 especially in West Africa. Indusia linear, attached along the vein. Spores with a few long folds above a papillate inner perispore.
Diplazium is often placed in Woodsiaceae, sometimes in Athyriaceae, families which are included in Dryopteridaceae here. Some authors propose placing Diplazium in Thelypteridaceae. The genus is closely related to Athyrium, from which it would differ by only one chromosome (n = 40 and n = 41 respectively) even though the chromosome number n = 41 is not consistent in Diplazium. Diplazium proliferum and related species with anastomosing veins are sometimes placed in a separate genus Callipteris.
Diplazium proliferum grows in Raphia thickets and marshes.
Diplazium species are easily grown from spores. The bulbils can be detached and placed in the soil for rooting, or they can be left on the plant to develop into plantlets which can be simply detached and planted.
Genetic resources and breeding
Diplazium proliferum is widespread and does not seem to be endangered. Although it is widely cultivated as an ornamental, it is not cultivated for use as a vegetable. No germplasm collections are known.
No special culinary merits are known of Diplazium proliferum and it seems unlikely that it has the potential to be grown and traded at a commercial scale. Its use as an ornamental remains important.
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Correct citation of this article:
van der Burg, W.J., 2004. Diplazium proliferum (Lam.) Thouars In: Grubben, G.J.H. & Denton, O.A. (Editors). PROTA 2: Vegetables/Légumes. [CD-Rom]. PROTA, Wageningen, Netherlands.