China has stolen a march on the West with the announcement that it is
to launch the first genetically engineered cigarette later this year. The
tobacco will come from the world鈥檚 largest plot of transgenic plants.
In trials over the past three years, Chinese biotechnologists have harvested
500 kilograms of dried leaves from trans-genic tobacco covering an area
of 1.5 square kilometres. The plants have been genetically modified to resist
the tobacco mosaic virus. 鈥榊ields have increased dram-atically, and the
farmers are really enjoying this,鈥� says Zhang-Liang Chen, head of the National
Laboratory of Protein Engineering and Plant Genetic Engineering at Peking
University.
鈥榃e took the leaves, dried them and made them into cigarettes,鈥� he explains.
The National Tobacco Testing Committee has been analysing the tobacco to
see if it differs in any way from normal tobacco. 鈥楳embers of the committee
are smoking them and say that they taste the same as non-transgenic cigarettes,鈥�
says Zhang-Liang.
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One group of the transgenic plants contained only half the usual amount
of nicotine, and Zhang-Liang hopes that these plants will help him to track
down the gene that controls nicotine content. 鈥業f we can fish out the gene
for nicotine content, we may be able to find ways of increasing levels.
If we can increase it, smokers will smoke fewer cigarettes and inhale less
tar, which is the most damaging component.鈥� Limited consumer trials are
already under way and the National Tobacco Company plans to market the cigarettes
more widely in the coming year. The cigarettes were originally given the
brand name 鈥楪ene鈥�, but smokers disliked it, so the name has been changed
to 鈥榗hina鈥�. 鈥榃e are pushing to get at least twice as much transgenic tobacco
planted this year,鈥� says Zhang-Liang.
Zhang-Liang鈥檚 team has also planted 80 hectares of transgenic tomato
plants. The plants have an extra gene which confers resistance to the cucumber
mosaic virus, which attacks tomatoes and reduces yields by 40 per cent.
After the crop fruited, the tomatoes were buried to prevent the seeds
from spreading more widely in the environment. But when farmers living near
the test fields saw how much riper the transgenic tomatoes were than those
from unaltered plants, they decided to help themselves.
鈥榃hen I buried the tomatoes, they thought I was crazy,鈥� he explains.
鈥楾hey crept to the site in the night, dug some of the tomatoes up and took
them home and ate them. Some farmers planted seeds from the tomatoes, but
only on a very limited scale.鈥� Zhang-Liang鈥檚 team has planted another 50
hectares with transgenic potatoes that have been made resistant to two viruses,
potato virus Y and potato virus X. 鈥楾hey grew beautifully,鈥� he says.
The Chinese test plots together make up the largest area of transgenic
plants in the world. But experiments with recombinant microbes cover a still
larger area. Five institutes are working with genetically engineered rhizobia,
bacteria that live in root nodules on certain plants and fix nitrogen from
the air.
Biotechnologists in China have added genes to those microbes so that
they fix more nitrogen. Over the past five years, the institutes have spread
the altered rhizobia over 10 square kilometres of rice, soya beans and wheat.
鈥業t鈥檚 not just a field trial now. Farmers are already using the microbes
as fertiliser and are spreading them on the fields,鈥� says Zhang-Liang. 鈥業t
increases their yields by 5 to 10 per cent.鈥� Zhang-Liang says that he understands
Western reticence about introducing genetically altered organisms into the
environment, particularly in the light of the existing agricultural overproduction.
鈥楤ut if I鈥檓 poor, like most of our 1.2 billion people, I think about what
I need to eat tomorrow,鈥� he says.
鈥楾he point I would like to stress is that for us, it鈥檚 a very useful
technology. It鈥檚 really helping the poor farmers. They are saving money
that they would otherwise spend on imported fertilisers and pesticides.鈥�
John Beringer, chairman of Britain鈥檚 Advisory Committee on Releases
to the Environment, is familiar with the trials. 鈥榃e鈥檙e a bit wary about
the large scale,鈥� he says. 鈥業鈥檓 not saying we would not let it happen here,鈥�
he adds, but stresses that he would want more information about the possible
spread of the borrowed gen-etic material from the transgenic plants to wild
ones before going ahead with such large experiments.
