Why are the seeds of this species difficult? The seeds are likely to be intermediate in storage behaviour. The seeds may also have morphological or morphophysiological dormancy, which would have to be overcome before they will germinate.
Coffea humbertii (Image: S. Wood, RBG Kew)
This species is likely to have Intermediate seeds (based on other species in the same genus). Some drying is possible, but viability will be lost if the seeds are stored at low temperatures.
Remove the covering structures of the seed before germination. Germinate on agar, germination paper or sand at 25°C. Germination and development may also be encouraged in-vitro, by excising the embryo and placing it on a supportive medium.
The seeds of this species may have Morphological or Morphophysiological Dormancy. In order to overcome morphological dormancy, the seeds may need to experience several 'seasons' to allow the embryo to grow and develop, before germination will occur. Mimick the seasonal patterns of the species' native habitat to overcome physiological dormancy. Use a moist pre-chill or pre-heat treatment (depending on local climatic conditions), before germinating the seeds on sand at their optimum temperature. If this does not work, you can perform delicate surgery to enable the embryo to grow. Excise the tissue near the root tip.
Coffea humbertii section
(Image: S. Wood, RBG Kew)
Accepted name: Coffea humbertii J.-F.Leroy
Synonyms: Paracoffea humbertii J.-F. Leroy
References and Links
- AFPD (African Flowering Plants Database) - Conservatoire et Jardin Botaniques de la Ville de Genève, Switzerland, and South African National Biodiversity Institute, Pretoria, RSA: Coffea humbertii.
- SID (Seed Information Database) - Royal Botanic Gardens, Kew, UK: Coffea humbertii.
- Tropicos - Missouri Botanical Garden, USA: Coffea humbertii.
- More about the Rubiaceae family