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The
seed bank is a repository for future generations
By
environment correspondent Alex Kirby
A visionary attempt to save many of the world's endangered
plants is to open in the United Kingdom at the end of
August.
It
is the Millennium Seed Bank (MSB), one of the largest
international conservation projects ever undertaken.
It
aims to have saved the seeds of more than 24,000 species
by 2010, a tenth of the global seed-bearing flora.
The
bank has already collected seeds from almost all the 1,400
or so British species suitable for inclusion.
Extinction
threatens more than 300 UK wild plants, and a quarter
of the world's plants could be condemned to vanish by
2050.
Cold
and dry
The
MSB is an initiative of the UK's Royal Botanic Gardens,
Kew. But it is housed, not at Kew Gardens in London, but
at its rural equivalent, Wakehurst Place in southern England.
Seeds
arriving at the MSB - it already has more than 250 million,
from almost 5,000 species - are first dried in conditions
of low humidity.
 Hugh
Pritchard takes extinction seriously
After several weeks their moisture level has fallen to
5%, which means they will last much longer - for about
200 years, the Bank's designers hope.
They
are then cleaned and checked, with a sample of about 50
of each species being X-rayed for quality.
Each
batch is tested for germination in dishes of agar jelly.
The test will be repeated every decade.
Finally,
they are placed in ordinary glass jars and stored in three
underground vaults at temperatures of -20 degrees C. The
number of seeds kept in a single jar is as great as the
number of people in many modern cities.
As
a precaution, a back-up seed collection is to be stored
in Scotland.
Securing
food
Most
of the seeds from abroad are from dryland species. The
project leaders say "off-site" conservation
like seed banking can contribute more "where land
degradation is brought about by climatic effects overlaying
unsustainable land use by indigenous people".
They
estimate that more than 60,000 sq kms are lost to deserts
every year. Dr Hugh Pritchard, head of research at the
MSB, told BBC News Online: "The drylands are fundamentally
important to the sustenance of something like 20% of the
world's population."
 Collecting
seeds in Burkina Faso
The MSB, which is costing more than £80 m, is planned
to be a centre of expertise, collaborating with the countries
from which the seeds originate.
The
project aims to help other countries to set up their own
seed banks, and plans to keep "a substantial proportion"
of all the seeds collected in their countries of origin.
Dr
Pritchard says the prospect of extinction is real enough
for many plants. "I think the threat is probably
worse than we imagine.
Untapped
potential
"If
we think about population expansion and the pressure that
will put on natural areas, those areas will decrease.
That has to mean we're going to lose species. Most of
the models do predict tremendous risk to plant species.
"Many
of the species that we currently conserve we perhaps don't
have an immediate use for. But something like 30% of the
medicines we use currently are based on products or chemicals
which have been extracted from plants.
"In
the future, if we are to find new remedies, we need to
have access to this cornucopia of plants worldwide."
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