Ipomoea batatas

Why are the seeds of this species difficult? Seeds harvested in the wild may have physical dormancy, which can be overcome by scarifying the seed coat to allow water uptake and encourage germination.

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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

Seeds harvested from plants growing in the wild may be Physically Dormant. Chip the seed coat with a scalpel before placing under germination conditions, in order to overcome dormancy. Alternatively, try immersing the seeds in sea water to soften the hard testa.

Based on the requirements for other species in this genus, germinate on agar, germination paper or sand at constant temperatures of 20 or 25ºC, or using an alternating temperature regime of 30/20ºC (with an 8/16hr photoperiod).

Seed Morphology

The dehiscent capsules (5-8 mm) float in water and are either hairless or have short, stiff hairs. Each capsule contains up to 4 seeds (3 mm), but usually only 1 or 2 develop. The hard seed coat is almost impervious to water. The seeds are angular and hairless. The cotyledons are bi-lobed and transversely folded.

See an image of this species at the Digital Atlas of Economic Plants.

Taxonomy

Family: CONVOLVULACEAE

Accepted name: Ipomoea batatas (L.) Lam.

Synonyms: Ipomoea batatas var. cannabina Hallier f., Convolvulus batatas L., Batatas edulis (Thunb.) Choisy, Convolvulus edulis Thunb.

Common name: sweet potato

References and Links

Food and Agriculture Organization of the United Nations and International Plant Genetic Resources Institute (1994). Genebank Standards. FAO/IPGRI, Rome, Italy.
International Seed Testing Association (2010). International Rules for Seed Testing: edition 2010. ISTA, Bassersdorf, Switzerland.
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: Ipomoea batatas.
PROTAbase (Plant Resources of Tropical Africa) - Wageningen, Netherlands: Ipomoea batatas.
SID (Seed Information Database) - Royal Botanic Gardens, Kew, UK: Ipomoea batatas.
Tropicos - Missouri Botanical Garden, USA: Ipomoea batatas.