Cajanus cajan

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.

Send your image to difficultseeds@kew.org

Seed Storage

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

Germination Requirements

Hard seeds may need scarification - chip with a scalpel if necessary. Sow on germination paper or sand and germinate using a constant temperature at 25ºC or under an alternating temperature regime of 30/20ºC (with an 8/16hr photoperiod).

The seeds of this species may be Physiologically Dormant (based on other species in the same genus). If germination is low, this type of seed 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.

Seed Morphology

See images of this species at the Digital Atlas of Economic Plants.

Taxonomy

Family: LEGUMINOSAE-PAPILIONOIDEAE

Accepted name: Cajanus cajan (L.) Millsp.

Synonyms: Cajanus indicus Spreng., Cytisus cajan L.

Common name: pigeon pea

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: Cajanus cajan.
PROTAbase (Plant Resources of Tropical Africa) - Wageningen, Netherlands: Cajanus cajan.
SID (Seed Information Database) - Royal Botanic Gardens, Kew, UK: Cajanus cajan.
Tropical Forages - CSIRO, DPI&F(Qld), CIAT and ILRI, Brisbane, Australia: Cajanus cajan.
Tropicos - Missouri Botanical Garden, USA: Cajanus cajan.