Gossypium herbaceum

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

Gossypium herbaceum germination (Image: S. Wood, RBG Kew)

Seed Storage

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

Germination Requirements

The seeds of this species are expected to be Physically Dormant (based on other species in the same genus).

Overcome dormancy by scarifying the seeds using a file. Germinate on agar, germination paper or sand at 20 or 25°C, or using an alternating temperature regime of 30/20°C.

Seed Morphology

Gossypium herbaceum , germinating seed
(Image: S. Wood, RBG Kew)

The fruit is made up of dehiscent locules, with the seeds contained in separate chambers. The oval-shaped seed (7 -11 mm) is protected by a seed coat and is black in colour. The seed has a densely hairy surface, a raphe and a hilum. The seed configuration is anatropous and the embryo type is axial-folded, filling more than 75% of the whole seed. The endosperm is reduced to only 5-6 layers of cells, or less. The embryo is white in colour with dark spots.

Taxonomy

Family: MALVACEAE

Accepted name: Gossypium herbaceum L.

Synonyms: Gossypium arboreum auct.

Common name: cotton

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.
Rao, N.K., Hanson, J., Dulloo, M.E., Ghosh, K., Nowell, D. and Larinde, M. (2006). Manual of seed handling in genebanks. Handbooks for Genebanks No. 8. Bioversity International, Rome, Italy.

AFPD (African Flowering Plants Database) - Conservatoire et Jardin Botaniques de la Ville de Genève, Switzerland, and South African National Biodiversity Institute, Pretoria, RSA: Gossypium herbaceum.
PROTAbase (Plant Resources of Tropical Africa) - Wageningen, Netherlands: Gossypium herbaceum.
SID (Seed Information Database) - Royal Botanic Gardens, Kew, UK: Gossypium herbaceum.
Tropicos - Missouri Botanical Garden, USA: Gossypium herbaceum.