Threats against plants

There are simply not enough protected areas in the world to conserve all plant species. Of those that do exist, most are small, fragmented and highly vulnerable to threats such as climate change, invasive alien species (introduced plants and animals), natural disasters and political instability.

What is seed banking?

Seed banking involves storing seeds for future use, therefore offering some insurance against the loss of plant species by extinction. Seed banking is a form of ex situ conservation that complements better known in-situ conservation approaches.

Banking or storing seeds of horticulturally significant species has been going on in some form since the advent of agriculture at least 13,500 years ago. However ‘conservation seed banking’ of wild plant populations is a much more recent response to the global decline of plant biodiversity.

Seed bank freezer unit

Figure 1. In the Tasmanian Seed Conservation Centre’s seed bank collections are stored in sealed foil packets and placed in a freezer unit at -20°C.

The process of seed banking involves:

  1. Collecting seeds from in situ wild plant populations.
  2. Drying the seeds down to approximately 15% relative humidity.
  3. Storing the seeds for future use at approximately -20°C (fig. 1).

Seeds are nature’s genetic storehouses; they occupy little space and require minimal attention over considerable periods of time. If banked correctly, most seeds can be grown into plants well into the future.

Banking seeds is recognised globally as a scientifically proven, highly efficient and cost effective method of conserving the variation within and between different plant species. Consequently in recent years modern, high-tech seed banks have been built in many countries around the world for the ex situ conservation of wild plant species.

By saving seeds, we can save plants

Hairy Cliff-Eyebright

Figure 2. Euphrasia phragmostoma flowering on the Tasman Peninsula. Photograph kindly provided by Micah Visiou.

In the case of highly threatened species a seed collection can often represent a far greater number of ‘potential genetic individuals’ (plants) than their habitat area can support in the wild. To demonstrate just how effective seed banking can be, consider the following example:
Euphrasia phragmostoma (Orobanchaceae, fig. 2) is a species endemic to a 1.6 km stretch of sea cliff on the Tasman Peninsula. Along this one stretch of cliff E. phragmostoma grows on narrow ledges and in cracks covering a total area of just over half a hectare. That’s an in situ population of around 700 individuals. By comparison, the seed collection for this species, safely stored in the ex situ seed bank, is of over 27,000 viable seeds.

Additional safe guards

For every seed collection made in Tasmania and stored in the Tasmanian seed bank, a duplicate collection is sent to the Millennium Seed Bank Project [external link]. This provides extra insurance against natural and man-made catastrophes.

Last refuge

Seed banking provides a last resort for the protection of plant species that are already condemned to extinction. Urgent candidates for seed banking are plant species under severe threat in the wild. The Millennium Seed Bank Project  in the UK, and its international partners (including the TSCC), identify endangered plant populations as a priority and attempt to collect seed before it’s too late.

A strict sampling procedure is necessary for plants that only exist in small numbers in the wild, to ensure the population is not diminished by seed collecting.

Australian Seed Conservation and Research (AuSCaR)

There is a fast growing global network of people involved in seed banking and related subjects, including people and organisations with research, conservation and/or industry backgrounds.

AuSCaR [external link] is an Australian network for the collection, storage, research and sustainable use of seeds for native plant conservation. Formed in 2007 of Australia-based Millennium Seed Bank partners, AuSCaR delivers seed banking of Australian flora in conjunction with botanic gardens, conservation agencies, universities and non-government conservation organisations.

More information about national and international seed conservation and research is available.

Other seed banks

For further information about other national and international seed banks, please visit:

Within Australia