Manihot esculenta

Why are the seeds of this species difficult? The seeds may have physiological dormancy, which can be overcome by mimicking the seasonal patterns of the species' native habitat.

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Seed Storage

This species has Orthodox seeds - dry to 15-20% eRH and store at -20ºC, or as cool as possible.

Germination Requirements

The seeds of this species may be Physiologically Dormant (based on other species in the same genus). File the micropylar end of the seed until the white embryo is just visible, to give rapid and fairly uniform germination. Place seeds on moist sand in a petri dish at 30ºC.

If germination is still low, overcome dormancy by mimicking the seasonal patterns of the species' native habitat. Use a moist pre-chill or pre-heat treatment (depending on local climatic conditions) or a dry after-ripening treatment, before germinating the seeds on agar, germination paper or sand at their optimum temperature.

Seed Morphology

The capsule (1.5 cm long) is globe-shaped and hairless, with narrow longitudinal wings. The fruits contain 3 ellipsoid seeds (12 mm long) with pronounced caruncles. The seeds are grey and mottled with dark blotches.

The woody endocarp splits explosively on ripening (3-5 months after pollination) and ejects the seeds.

Taxonomy

Family: EUPHORBIACEAE

Accepted name: Manihot esculenta Crantz

Synonyms: Manihot utilissima Pohl, Jatropha dulcis J.F.Gmel., Manihot dulcis (J.F.Gmel.) Pax

Common name: cassava, manioc, tapioca

References and Links

Food and Agriculture Organization of the United Nations and International Plant Genetic Resources Institute (1994). Genebank Standards. FAO/IPGRI, Rome, Italy.
Purseglove, J.W. (1968). Tropical Crops: dicotyledons. Longman Group Ltd., UK.

AFPD (African Flowering Plants Database) - Conservatoire et Jardin Botaniques de la Ville de Genève, Switzerland, and South African National Biodiversity Institute, Pretoria, RSA: Manihot esculenta.
SID (Seed Information Database) - Royal Botanic Gardens, Kew, UK: Manihot esculenta.
Tropicos - Missouri Botanical Garden, USA: Manihot esculenta.