Seed Science Team

Background

The Seed Science team undertakes integrated research in a number of areas vital to improving the efficiency of use of native seeds in conservation and restoration. Research is targeted at seed collection, storage, propagation and delivery to site. Of these areas, seed germination and dormancy is the predominant area of investigation, as a limited understanding of seed germination requirements impacts on all seed research areas. The Seed Science team collaborates with national and international partners, including other state botanic gardens and the Millennium Seedbank, Royal Botanic Gardens, Kew, UK, and works closely with Western Australian universities, the mining and agricultural industries and landcare groups to ensure research outcomes are disseminated to the wider community.

Key research areas:

Research into seed germination and dormancy is a major area of investigation as effective methods for seed propagation underpin practically all uses of seeds in conservation, restoration and horticulture. This research is particularly focused on understanding the role of temperature and moisture in controlling seed dormancy status. This includes investigating and optimising the application of dry after-ripening, warm stratification and cold stratification protocols for dormancy loss. Key families that are the focus of dormancy research include Cyperaceae, Restionaceae, Dilleniaceae and Ericaceae.
Germination research is also focused on the use of germination stimulants, including gibberellic acid and smoke products. Testing of a novel butenolide compound, identified as the germination-active principal in smoke, is a new area of research. This compound has broad ranging action across natives, weeds, agricultural and horticultural species. Field trials are evaluating butenolide as a means to promote germination of the soil seedbank of both native species and agricultural weeds.
Understanding seed storage behaviour is necessary to ensure conservation collections of wild collected seeds are banked under conditions that will maximum longevity. Research is focused on characterising seed storage physiology, employing rapid aging techniques to rank species longevity for identifying long- and short-lived species and determining the effects of the storage environment on seed dormancy status.
Research targeted at developing and adapting seed enhancement technologies to seeds of native species is key to improving the efficiency of use of seeds in restoration. The use of seed priming techniques, application of polymer seed coats and the use of germination stimulants such as gibberellic acid and butenolide, and anti-stress agents such as salicylic acid as current focal areas. Projects are also defining the role of predation and abiotic factors (wind and water erosion) in seed loss following broadcasting.

Key outcomes:

Warm stratification is proving to be an effective means of dormancy alleviation for a number of species from difficult to propagate families, including Dasypogonaceae, Dilleniaceae and Restionaceae. Results indicate temperature and moisture are primary drivers of dormancy loss, and that some species require the subsequent addition of stimulants such as smoke and gibberellic acid for germination.
Significant interactions between butenolide and the plant growth regulators gibberellic acid and abscisic acid have been demonstrated on model Australian species, providing insights into the mode of action of smoke in germination stimulation.
For the first time a reliable technique for seed germination of Atriplex species has been developed. This is a significant breakthrough for saline land restoration and pasture development in the use of native species for perennial pasture and agricultural land restoration.
Seed priming methods have proved to be highly effective in increasing the rate and synchronicity of germination of a wide range of native species. These priming techniques may be implemented by nursery staff to improve large-scale seed-based propagation of plants for land rehabilitation programs.
A rapid aging protocol to determine comparative seed longevity is proving to be an efficient means of ranking species longevity. This program is run in collaboration with the Millennium Seedbank, Royal Botanic Gardens, Kew, UK and is assisting in a global program to identify species producing long- and short-lived seeds.

Current Research Projects:

Discovery of the physiological and molecular modes of action of butenolides in promoting seed germination and vigour in plants. Collaborators: Prof. S. Smith (The University of Western Australia). Funding: ARC-Discovery, 2006 - 2008.
Western Australian Seeds Program. Collaborators: Millennium Seedbank, Royal Botanic Gardens, Kew, UK; Department of Conservation and Land Management; Greening Australia WA. Funding: Millennium Seedbank, Royal Botanic Gardens, Kew, UK, 2005 - 2009.
Optimising synthesis, developing delivery systems and resolving the ecological significance of the chemical in smoke that promotes seed germination. Collaborators: A/Prof. E. Ghisalberti (The University of Western Australia), A/Prof. R. Trengove (Murdoch University). Funding: ARC-Discovery, 2005 - 2007.
A physiological and biochemical basis for seed storage for biodiversity conservation and restoration. Collaborators: A/Prof. David Turner (The University of Western Australia). Funding: ARC-Linkage; Iluka Resources; Rocla Quarry Products; MERIWA; GAWA; Alcoa World Alumina Australia, 2005 - 2007.
Optimising collection, storage and germination of native plant species. Funding: ACMER, 2005 - 2007.
Mechanisms for release of deep dormancy in seeds of Australian plant species used in Land Restoration. Collaborators: A/Prof. J. Plummer (The University of Western Australia). Funding: ARC-Linkage, 2004 - 2006.
Grass roots - native perennial grasses for sustainable pasture systems. Collaborators: Dr Megan Ryan (The University of Western Australia), Ian Chivers (Native Seeds Pty Ltd), Dr Meredith Mitchell (Department of Primary Industries, Victoria, CRC for Plant-Based Management of Dryland Salinity). Funding: RIRDC, 2005 - 2008.
Reliable establishment of non-traditional perennial pasture species. Collaborators: Dr Ed Barrett-Lennard (AGWA), Dr Megan Ryan (The University of Western Australia). Funding: CRC for Plant-Based Management of Dryland Salinity, Sustainable Grazing of Saline Lands (SGSL), Meat and Livestock Australia (MLA) and Australian Wool Initiative (AWI), 2006 - 2009.

Seed Science Team