Theme: Ecophysiology and Morphology

Thermogradient plate used in ecophysiology experiments

This ‘meta-project’ is one of seven groupings of projects around common themes within the Millennium Seed Bank Project’s science and technology programme.

Among the most important elements of the MSBP’s science and technology programme is the need to understand seed germination behaviour, and to develop practical methods for germinating seeds of a very wide range of species from diverse habitats. Whatever the ultimate use of conserved seeds, it is always the growing plant that is required in the future; and without practical treatments to convert seeds to plants these uses cannot be realised. Moreover, the seed germination test remains the most reliable method available for monitoring the viability of seed conservation collections.

Species’ seeds often show adaptations to their environments, presumably to maximise the chances of seedling survival. These operate, for example, by cueing germination to particular seasons and/or micro-sites. Adaptations may be morphological (usually visible and highly heritable), e.g. water impermeable seed coats, underdeveloped embryos at maturity; or they may be physiological (cryptic and frequently quite plastic). An understanding of the environmental regulation of seed processes in relation to morphology and embryo physiology should enhance our ability to develop appropriate methods for overcoming dormancy and stimulating germination in the seeds from widely diverse species and sources. The extensive nature of seed germination testing and the recording of seed morphology (see Annex 1) at the Wellcome Trust Millennium Building have already significantly benefited the wider scientific community by being made available in the Seed Information Database. It is intended that this impact will not only continue, but will be extended; for example through the development of predictive, decision-support tools for germination.

Significant achievements and outputs (2001-2005)

Members of the group have: solved seed germination problems in 217 collections that failed routine MSB testing; delivered 2 major reviews of seed dormancy; shown how life history traits affect seed germination responses to smoke in > 200 species; quantified the interactive effects of dry heat and smoke as germination stimulants (55 species from 27 families); widened understanding of the occurrence of physical dormancy in seeds, and used acid and / or extreme dry heat (fire simulation) to overcome such ‘dormancy’ in a broad range of dry-land sp.; identified and introduced for routine application a surgical excision method for removing seed dormancy in tropical grasses; explained the effect of alternating temperature on seed germination in 6 cacti, and revealed high temperature triggering of germination in a gap detecting species; related low temperature seed response in an African species to its upland origin, and modelled type II physiological dormancy loss in a species in response to chilling; reviewed ecological aspects of palm species germination with desiccation physiology; initiated a PhD on seed dormancy (in Queensland Australia); delivered a review of seed morphology, put seed images for 350 species on the web (in SID) and applied a novel X-ray scanning technique to plant material; used seed characters to aid classification in cacti.

Projects on this theme:

Project Team

Project Leader: Dickie, John B.

Seed Conservation Department

Natasha Ali, Matthew Daws, John Dickie, Fiona Hay, Simon Linington, Kenwin Liu, Rosemary Newton, Hugh Pritchard, Robin Probert, Wolfgang Stuppy, Peter Toorop

Funders

UK

Millennium Commission

Annex Material

Annex 1: Seed Morphology and Anatomy in the MSB Project  (Word document)

Annex 2: Information outputs associated with this theme   (Word document)