Why are the seeds of this species difficult? The seeds of some wild-growing sub-species may have physiological dormancy. This can be overcome by mimicking the seasonal patterns of the species' native habitat.
Lycopersicon esculentum (Image: S. Wood, RBG Kew)
This species 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 (top of paper or between paper) or sand under alternating temperature regimes of 35/20ºC or 30/20ºC (with an 8/16hr photoperiod).
The seeds of this species may have non-deep Physiological Dormancy. If germination is low, overcome dormancy 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.
Lycopersicon esculentum section
(Image: S. Wood, RBG Kew)
The fruit (2-15 cm) is a fleshy berry, globose or depressed at either end, smooth or furrowed. The fruit is hairless and shiny when ripe, and red or yellow in colour. The seeds (3-5 x 2-4 mm) are numerous, kidney-shaped and hairy. The embryo is curved and embedded within the endosperm.
Accepted name: Lycopersicon esculentum Mill.
Synonyms: Solanum lycopersicum L., Lycopersicon lycopersicum (L.) H.Karst.
Common name: tomato
References and Links
- Baskin, C.C. and Baskin J.M. (1998). Seeds: ecology, biogeography, and evolution of dormancy and germination. Academic Press, USA.
- 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.
- Purseglove, J.W. (1968). Tropical Crops: dicotyledons. Longman Group Ltd., UK.
- 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: Lycopersicon esculentum.
- AVRDC - The World Vegetable Centre, Taiwan: fact sheet on Lycopersicon esculentum.
- PROTAbase (Plant Resources of Tropical Africa) - Wageningen, Netherlands: Lycopersicon esculentum.
- SID (Seed Information Database) - Royal Botanic Gardens, Kew, UK: Lycopersicon esculentum.
- Tropicos - Missouri Botanical Garden, USA: Lycopersicon esculentum.