The agriculture industry depends on about 150 crops grown on a significant scale worldwide. This, obviously, is not very many. Preserving them all, and more, is integral to a functioning ecosystem. Each crop plays a vital role in our delicate global balance, with different traits ranging from tolerances to pests and disease to drought resistant plants that require less water. Preserving the existing varieties of crops is crucial to ensure that productive harvests continue indefinitely. For many, the decrease in biodiversity is far from their radar, but as the global population increases and diseases become more virulent, staunching it will be a global effort.
Enter the seed bank – a storage facility for seeds. Types of seeds stored include food crops and rare species. Rare species of seeds are often stored in order to preserve seed diversity as well as the heritable traits in seed varieties. Seed banks also aid plant breeders in the enormous task of breeding crop varieties that deliver higher yields, improved pest and disease resistance and the ability to thrive in extreme growing conditions.
Biodiversity has declined in recent years due to developments in agriculture aimed at increasing the productivity of selected plants, animals and microorganisms. Ranching is a famous example of this – a new breed of cattle is lost every month but those who do survive are able to produce an enormous amount of food. Reducing biodiversity, while highly beneficial in the above sense, also has serious downsides. According to the UN Food and Agriculture Organization, 75 percent of the genetic diversity of crops has been lost. The selection of fruit and vegetables harvested for sale in the developed world is dominated by heavy cropping, reliable varieties with a long shelf life. The United States had 7,100 apple varieties in the 19th century. Presently, only 300 remain.
Seed banks are an efficient and cost effective way to preserve genetic diversity for future conservation work. The practice of storing seeds is advantages in a variety of ways: seeds can be cultivated into plants for restoration purposes regardless of season; seed storage allows for a greater collection of genetic diversity than individual plants in living collections; seeds occupy very little space and are more compact than living plants; seeds can be stored for a considerable length of time; and duplication of seeds at multiple seed banks provides a safeguard against accidental loss at one location.
A Goliath among seed banks, the Svalbard Global Seed Vault is a backup facility for the world’s 1,750 seed banks, housing a total of 750,000 seed samples – about two-thirds of the world’s stored crop biodiversity. The epitome of meticulous planning and security, the Svalbard is located in the permafrost of Norway’s Arctic archipelago, one of the world’s most northerly habitations. It is maintained at a constant temperature of -18°C. If disaster were to cut off its electricity supply, two centuries would pass before the vault warmed up to freezing point.
Damage and security threats to seed banks are not taken lightly, due to the precious cargo housed within. Destruction or theft could mean the loss of years of scientific research, not to mention rare or nearly extinct seed species.
The Global Crop Diversity Trust (GCD) backs the Svalbard Seed Bank. GCD is a public-private partnership raising funds from individual, corporate and government donors to establish an endowment fund that will provide complete and continuous funding for key crop collections. The Trust’s mission is to advance an efficient and sustainable global system of off-site plant conservation by promoting the rescue, understanding, use and long-term conservation of valuable plant genetic resources.
The examples above illustrate the efforts that are ongoing to conserve plant biodiversity in a time of unprecedented species loss. While we cannot recoup what we have already lost, it is entirely possible to foster the diversity of the species we do have and continue moving forward.
Meika Jensen, 2012
Meika has also written for the MastersDegree.net website
Sowing the Seeds of Biodiversity Conservation: Part Two – The Millennium Seed Bank Partnership
The advantages of long-term seed storage for crop plant biodiversity conservation, as clearly set out by Meika Jensen, apply equally to wild species. Indeed, the techniques and standards developed by the crop gene banks in the middle of the last century were borrowed and adapted by a few botanic gardens and others interested in the ex situ conservation of wild seed plant species. One of the early pioneers was Professor César Gómez-Campo, who established a seed bank primarily for Crucifers at the Universidad Politécnica de Madrid, Spain in 1966. His contemporary was Dr Peter Thompson who founded the Kew Seed Bank; which, following substantial support from the UK Millennium Commission and other major donors, became the Millennium Seed Bank. Having built and occupied a new building for the purpose, as well as collecting and storing seed samples of almost all of the UK’s native species, the Millennium Seed Bank Project grew into an international network of partners, led by Roger Smith, and later Paul Smith (no relation!), operating under the terms of the Convention on Biodiversity. From 2000-9 the Project collected and put into secure storage representative samples of more than ten percent of the world’s wild (non-domesticated) seed plant species, focusing on those that are endangered, endemic, or used directly by man. With its focus on non-crop species, the MSB is essentially complementary to the Svalbard Global Seed Vault. It is also distinct from the latter in being engaged in active processing and testing of the collections and research on them, rather than employing a virtually un-manned, ‘black-box’ methodology.
Since 2010 the MSB Project has evolved into the MSB Partnership (now 152 partner institutes in 54 countries, and growing). As well as the very challenging target of collecting and storing seeds from a further fifteen percent of the world’s seed-bearing species by 2020, the Partnership also now has the explicit additional aim of promoting the sustainable use of its collections, data and expertise. Such uses include: species reintroductions; habitat restoration; sustainable utilisation aimed at improving livelihoods; and research. The MSB is not merely a repository, but a ‘bank,’ in the sense that users can withdraw samples, to grow into plants for a multitude of purposes. For example, seed samples have been sent out for research into better adapted species and varieties: salt tolerant pasture species in Australia; drought tolerant forage species in Egypt and Pakistan; forage grasses for pasture breeding in New Zealand; and many more. For most people in a crowded world with competition for land and resources, nature conservation for its own sake has limited appeal, and they will only continue to support it if they can see outcomes for mankind through sustainable use.
With the total number of seed plant species well in excess of 300,000, and under resource limitation, the MSB’s approach to capturing sub-specific variation has inevitably been different from that of crop seed banks, whose primary goal was the comprehensive preservation of genotypes within around a hundred species. The MSB continues to strive to cover biodiversity at the level of species and above. Nevertheless, the importance of sub-specific variation is well recognised; and as well as adding more species to the bank, increasing attention is being given to multiple collections of species, especially where factors such as breeding system and population isolation indicate that this should be a priority.
An example of the MSB’s move to increased sub-specific sampling is in its ongoing programme of collecting the UK native flora: the overwhelming majority of species are represented, and efforts are now focused on eco-geographic sampling within species. Use of appropriate (local) provenance material is particularly important in vegetation and habitat restoration, and the need to do this at a landscape scale is one of the key elements of ‘Making Space for Nature’. Recognition that specialist UK native seed companies offer a limited range of species, with often poor seed quality, and that RBG Kew’s horticultural and seed banking expertise could support commercial companies and restoration practitioners, has led to the birth of the UK Native Seed Hub. This project aims to: help improve the quality, availability and appropriateness of UK native seed: support the native seed industry in responding to predicted increased demand; and thus support restoration, enhancement & reintroduction initiatives in the UK. It is multiplying samples of the MSB’s conservation collections, to provide seed companies with stocks that they can further multiply on a commercial scale. At first, the target plant community is the species-rich neutral meadows of the High Weald of Kent and Sussex, where only three percent of meadows existing before WW2 continue to do so, with consequent negative effects on the diversity and abundance of insect pollinators and other wildlife.
In the UK it is also worth mentioning that the MSBP is at the early stages of collaborations with both the National Trust and several major botanic gardens in addition to Kew, to collect and conserve seeds of their horticulturally important collections. Similarly, there is an MOU with the Forestry Commission, to work together on seed collections and share expertise on species important to forestry, in the UK and worldwide.
Finally, returning to crop seed banks; the area in which they and wild species seed banks like the MSB overlap is in the immediate wild relatives of crop species. Many of these species are, or may be threatened in the wild, and yet they may harbour genes and traits of vital importance to the improvement of crop yields, disease resistance and adaptation to changing climate. The MSB holds more than 1500 collections of crop wild relative species, including those of wheat. RBG Kew is part of the ‘Adapting Agriculture to Climate Change Project’, which will be co-managed by the MSB and the Global Crop Diversity Trust, funded to the tune of $50 million over next 10 years by the Norwegian Government. The MSB is responsible for coordinating collecting and processing seeds from CWRs of 23 major crop gene-pools including all of the UK’s main crops (wheat, barley, oats and potatoes).
For more information, follow this link:
http://www.kew.org/science-conservation/save-seed-prosper/millennium-seed-bank/index.htm
John Dickie
John Dickie is Head of Botanical Information in RBG Kew’s Seed Conservation Department, which is based at Wakehurst Place in Sussex, and is a centre for the Millennium Seed Bank Partnership.