Why are the seeds of this species difficult? The seeds may have both physical and physiological dormancy. For germination to occur, both types of dormancy may need to be broken.
Berchemia discolor (Image: S. Wood, RBG Kew)
This species has Orthodox seeds - dry to 15-20% eRH and store at -20ºC, or as cool as possible.
The seeds of this species may have Combinational Dormancy (based on other species in the same genus), as they have impermeable seed coats (physical dormancy) and physiologically dormant embryos.
For germination to occur, both types of dormancy must be broken. Overcome physical dormancy by removing or chipping the seed covering structures before sowing to allow water uptake. Physiological dormancy can be overcome 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. If this does not work, you can perform delicate surgery to enable the embryo to grow. Excise the tissue near the root tip.
The fruit (20 mm x 8 mm) is a one- to two-seeded drupe. The flat seeds are enclosed in a sweet, edible flesh.
The fruit skin turns yellow during ripening.
Accepted name: Berchemia discolor (Klotzsch) Hemsl.
Synonyms: Phyllogeiton discolor (Klotzsch) Herzog; Scutia discolor Klotzsch
Common name: wild almond
References and Links
- Food and Agriculture Organization of the United Nations and International Plant Genetic Resources Institute (1994). Genebank Standards. FAO/IPGRI, Rome, Italy.
- Janick, J. and Paull, R.E. (eds) (2008). The Encyclopedia of Fruit and Nuts. CAB International, UK.
- AFPD (African Flowering Plants Database) - Conservatoire et Jardin Botaniques de la Ville de Genève, Switzerland, and South African National Biodiversity Institute, Pretoria, RSA: Berchemia discolor.
- PROTAbase (Plant Resources of Tropical Africa) - Wageningen, Netherlands: Berchemia discolor.
- SID (Seed Information Database) - Royal Botanic Gardens, Kew, UK: Berchemia discolor.
- Tropicos - Missouri Botanical Garden, USA: Berchemia discolor.