|
2003
2ND PLACE
One day well
rute the departure of Daniel, Ebeneezer and the District Nurse
William McDowall
2nd
place winner of the 20-28 category
The Daniel's Defiance runner bean, which
once graced allotments across the country, may soon join dodos
and dinosaurs on nature's rejects' pile. While most acknowledge
that losing an obscure vegetable variety would be a shame, few
of us are likely to lose much sleep over it. Runner beans, however
delightfully named, simply can't match pandas or polar bears for
conservation appeal.
We should be more concerned. Agricultural biodiversity is an important
part of our national heritage, explains Bob Sherman from the Henry
Doubleday Research Association's Heritage Seed Library -
and not simply because the Daniel's Defiance might taste nice.
The erosion of crop genetic diversity at all levels (diversity
of species, of varieties, and even genetic diversity within a
crop variety) may threaten the future of farming.
In nature, diversity provides insurance - any child can tell you
that eggs are safer in a variety of baskets. The Irish potato
crop in the mid-19th century was devastated because of the genetic
uniformity of the plants. Potatoes are propagated clonally rather
than sexually, and most of Ireland was planted to a narrow gene
pool. In a diverse system, some of the plants might have been
resistant to potato blight, and disaster could have been averted.
Diversity is not just about insurance within the field - it's
about securing our crops for future generations. As gardeners
can attest, plants have to fight to stay alive (this can border
on the obsessive - my mother frequently claims to be kept awake
at night by the sound of slugs munching on her larkspurs). Species
alive today are here because their ancestors were the best, the
toughest, the fittest. Traditional crop varieties are the result
of both natural selection and generations of farmers' breeding.
They are adapted to the conditions in which they have evolved
- desert plants tolerate drought, those from high-level latitudes
shrug off frost.
The genes that plants contain make up a library of solutions to
the problems that those ecosystems pose to survival. This is our
genetic heritage, and one of humanity's most valuable yet endangered
resources. Crop breeders need nature's library to develop new
varieties which incorporate the best traits from traditional crops.
But the library has been slated for redevelopment, and the bulldozers
have moved in. Traditional varieties are being replaced by their
modern, higher yielding counterparts all over the world. This
is fine for food production, but if the unique genetic strategies
contained in those traditional varieties are lost for ever, it
is very bad news for the long term future of agriculture. Genetically
uniform, high-yielding varieties all succumb to pests or disease
eventually, and if yields are to be sustained we need new sources
of resistance.
One answer to this problem of genetic erosion is to collect the
seeds of as many varieties as possible and store them for future
use. This takes up little space, and is a relatively cheap and
efficient way of preventing the loss of genetic material. The
problem is that seeds can't do much evolving in a drawer, and
with evolution put on ice, the varieties we store today will not
develop resistance to the pests of tomorrow.
Seed banks need backup, and this comes from in situ conversation,
in which diverse varieties continue to be grown in the habitats
in which they evolved. At the Heritage Seed Library, Bob Sherman
and colleagues not only maintain a seed bank, they also distribute
hundreds of seeds for gardeners to grow in allotments and vegetable
plots around Britain - keeping the turnips on their toes, as well
as providing gardeners with unusual and tasty vegetables.
Of course, runner beans and onions aren't the only plants that
we depend on. Major crops, such as wheat and potatoes, all have
centres of diversity far from Britain, and it is there that diversity
must be maintained, but the principle is the same worldwide. It
would be more than a shame to lose this rich genetic heritage,
so spare a thought for the Ebeneezer onion and the District Nurse
climbing bean - their genes might one day save the crop.
The author, 24, is finishing
his masters thes s at Leeds and came second in the older category
of the BASF/Daily Telegraph science writing competition. He received
his at the British Association's festival in Salford
|
|
|
