Top of the crops
BY JOHNJOE McFadden
The Guardian http://www.guardian.co.uk
WHILE we in the west are preoccupied with cloning sheep, pigs, dogs
and, of course, ourselves, scientists in the developing world are
focused on an organism of far greater importance: rice. According to a
Chinese saying, "the most precious things are not jade and pearls but
the five grains".
Rice the staple food crop |
Earlier this month the genome of one of those five grains was laid
bare when the complete genome sequence of rice was published in the
journal Nature.
Rice is the staple food crop for 3 billion people, mostly in Asia.
But most of those dependent on the crop still go hungry.
About 800 million people don't have enough to eat, many of them
children, and about 5 million will die of diseases related to
malnutrition. And with the world's population increasing at a rate of
about 86 million people a year, things could get a lot worse.
It is estimated that rice production will have to increase by about
30 per cent in the next 20 years to keep pace with population growth and
economic development. Where is all the food going to come from?
There are two principal ways to boost food production: increasing the
amount of land under cultivation or increasing yields. Until the 60s the
favoured strategy was putting more land under the plough, resulting in
the loss of much of the world's wilderness and native forest.
But in the 60s plant breeders such as Norman Borlaug pioneered a new
strategy, increasing crop yields through a mixture of seed improvement
and technological inputs: the green revolution.
As crops of the new varieties were planted, first in Mexico and then
throughout the world, particularly in Asia, harvests soared and have
continued to rise at a rate of about 2 per cent a year.
But the green revolution is grinding to a halt. There have been only
small yield increases in recent years, and it is thought that rice grown
on the most productive irrigated land has now achieved maximum
production levels.
The challenge for the future is to increase yields in more marginal
lands, where much of the crop ends up in the bellies of insects or is
devastated by drought or disease.
Many scientists (including Borlaug) believe that the only way to
provide food security for the world's poorest people is to genetically
engineer crops that are more resistant to nature's ravages.
The potential value of GM crops was highlighted earlier this year
with the publication of the results of a Chinese study that demonstrated
a 10 per cent increase in yield for farms that planted an
insect-resistant GM variety of rice.
In a typically Chinese understatement, Professor Jikun Huang, the
director of the Centre for Chinese Agricultural Policy at the Chinese
Academy of Sciences, said: "The performance of insect-resistant GM rice
in trials has been impressive."
Not only were yields up, but the use of pesticides dropped by 80 per
cent and farmers reported a dramatic reduction in pesticide-related
health problems.
But inserting a single gene is just tinkering. What the rice genome
project provides is a blueprint of the entire genome and the capability
to engineer the crop to meet the needs of farmers throughout the world.
The rice genome was sequenced by the International Rice Genome
Sequencing Project, a unique collaboration of researchers in Japan,
China, Taiwan, Thailand, Korea, the US, Canada, France, India, Brazil,
the Philippines and the UK.
The project, with its insistence on making its data immediately
available to scientists anywhere in the world at no cost, is a glowing
example of one of the positive benefits of globalisation:
internationally collaborative science that can benefit the entire world.
Even before publication, researchers had already mined the rice genome
data to identify novel genes.
Of course, many aid organisations - often heavily influenced by
western green campaigns - have attacked the emphasis on GM technology,
calling it a 'technical fix' that does little to address the real social
and economic causes of world poverty and hunger.
They said the same several decades ago when widespread famine was
predicted to follow a population explosion.
The population explosion materialised but the famine didn't. The
reason was that while others argued for social reform, pioneering plant
breeders launched the green revolution and saved millions from
starvation.
The Human Development Report 2001, commissioned by the United Nations
development programme, concluded that "many developing countries might
reap great benefits from genetically modified food crops and other
organisms".
Some 1.2 million people live on less than one dollar a day, and that
dollar usually buys rice. But the crop is prone to many diseases, pests
and unpredictable climate change.
Genetic engineering of crops to generate new varieties resistant to
disease, pests, drought and salinity could revolutionise third-world
farming. The release of the rice genome sequence places a powerful
toolkit in the hands of researchers eager to improve crop yields.
(Courtesy - The Guardian)
(The writer Johnjoe McFadden is professor of
molecular genetics at the University of Surrey and author of Quantum
Evolution) |