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.
Lagenaria siceraria (Image: W. Stuppy, RBG Kew)
This species most probably has Orthodox seeds. To avoid a decline in viability, remove seeds from ripe fruits soon after harvest and allow to dry slowly, under ambient conditions, before transferring to a cool dry room. Dry to 15-20% eRH and store at -20ºC, or as cool as possible.
Germinate on agar, germination paper or sand, using constant temperatures of 20, 25 or 30ºC, or under an alternating temperature regime of 30/20ºC (with an 8/16hr photoperiod). Incubating the seeds in 24hr darkness may also help germination.
The seeds of this species may be Physiologically Dormant (based on members of the same family). 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.
The fruit is a fleshy, indehiscent pepo with many seeds. Each seed (10-17 mm x 6.0-7.0 mm x 2.3-3.1 mm) is protected by a seed coat. The seed is brown in colour and laterally compressed. The seed surface is smooth, with a raphe, a small hilum and a pleurogram. The seed configuration is anatropous. The white embryo is axial-investing, taking up the whole seed.
Accepted name: Lagenaria siceraria (Molina) Standl.
Synonyms: Lagenaria vulgaris Ser.
Common name: bottle gourd
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: Lagenaria siceraria.
- AVRDC - The World Vegetable Centre, Taiwan: fact sheet on Lagenaria siceraria.
- PROTAbase (Plant Resources of Tropical Africa) - Wageningen, Netherlands: Lagenaria siceraria.
- SID (Seed Information Database) - Royal Botanic Gardens, Kew, UK: Lagenaria siceraria.
- Tropicos - Missouri Botanical Garden, USA: Lagenaria siceraria.