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Is GM the answer to the food crisis?

As the price of food soars, countries are looking to the biotechnology industry to help increase harvests. But can genetic modification really increase yields? Li Taige investigates and finds further research is needed.

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As global food prices continue to soar, biotechnology firms and advocates are lining up to argue that gene technology can solve the world’s food shortages. 

China, too, has ambitions in the research and application of genetically modified (GM) crops. Government plans for the industry include the development of pest- and disease-resistant GM rice, rapeseed, maize and soy. Development of new GM crops is one of the 16 major projects listed in the country’s plan for mid- to long-term scientific and technological development (from 2006 to 2020). It will be China’s most expensive agricultural science undertaking of all time, with research focussing on yields, quality, nutritional value and drought-resistance.

So, can GM crops actually increase food production? 

GM technology transplants novel genes into an organism in order to improve it in some way. In GM crops that are already being tested or commercially farmed, genes have been added to increase resistance to pests, disease and herbicides – but never to directly increase harvests.

However, these changes can – at least in theory – increase yields. This is the viewpoint taken by the International Service for the Acquisition of Agri-biotech Applications’ (ISAAA) 2007 report, Global Status of Commercialized Biotech/GM Crops, which says GM technology can increase production.

In India and China, fields of pest-resistant GM cotton need 50% less pesticide than non-GM strains. The technology has been responsible for harvest increases of 50% in India and 10% in China. The GM strain has an additional gene – known as Bt, for the Bacillus thuringiensis bacteria from which it originates – which produces a poison that kills off certain pests that attack cotton plants.

Cotton is not a food crop, but some argue that the same technology could also be used to increase maize production. In South Africa, Richard Sithole, chair of the Hlabisa District Farmers’ Union, reported that 250 poor, small-scale farmers planted GM maize with the Bt gene on their plots, which averaged at 2.5 hectares per household. His own harvests rose by 25%, worth an extra US$300, and some farmers reportedly saw increases of 40%.

Among all modified food crops, it is GM rice that is drawing the most attention. In China alone there are 110 million rice farmers, with an average 0.27 hectares of land per capita. The impact of increased harvests would be massive. 

Iran is the only country to have approved the commercial growing of GM rice. But China has spent significant amounts on researching this area. Four pest-resistant strains have passed intermediary testing and environmental release trials, and are now undergoing large-scale planting trials – the forerunner of commercial use.

A research team led by Huang Jikun, head of the Centre for Agricultural Policy at the Chinese Academy of Sciences, carried out a survey of pre-production trials on two strains of pest-resistant rice. The ISAAA quoted this study as saying the strains could increase yields by between 2% and 6%, and reduce the use of pesticides by almost 80%.

However, a paper by Huang’s research group, published earlier this year in the journal Economic Development and Cultural Change, revised this claim. The villages where GM rice was planted did see an increase in harvests, they said, but households where both GM and non-GM rice were planted did not see any improvement. They say there is no evidence from randomised and controlled trials that GM rice does increase harvests.

One reason may be that the trials were not actually randomised; village officials may have chosen better farmers to participate in the tests. Whatever the reason, more research is needed before to ascertain whether pest-resistant rice increases yields or not. Even if it does not increase yields, but does reduce pesticide use and labour input – while presenting no health or environmental risks – then it will help to slow the rising cost of food.

There also may be a new hope for the use of GM rice to raise yields, as reported in a paper by Zhang Qifa and his research group at Huazhong Agricultural University, published in May 2008 issue of Nature Genetics. The research group discovered for the first time a single gene that controls stalk height, flowering time and the number and size of grains. Theoretically, this gene can be used to increase productivity. For now, however, this possibility only exists on paper.

Debate rages over the use of GM technology in other food crops besides rice. Some research has found that GM technology actually can result in smaller harvests. A recent study by Barney Gordon of Kansas University, published in Better Crops, found that yields from a Monsanto-produced strain of herbicide-resistant soy were 10% lower than from conventional varieties.

The International Assessment of Agricultural Knowledge, Science and Technology for Development (IAASTD), which was produced by 400 experts from around the world over a period of three years, reflects this controversy. Limited research data on some GM crops in certain years show increased yields of 10% to 33%, while others see lower harvests. The report, therefore, makes a cautious assessment on whether GM crops can meet the increased demand for food. With GM technology developing rapidly, it says, long-term evaluations of the risks and benefits for health, the environment and the economy are lagging behind.

The IAASTD report has been accepted by 57 nations, including China. The Daily Telegraph, a British newspaper, interpreted the report as saying that GM technology did not offer a solution to food shortages. However, the IAASTD did not entirely reject the idea that GM has a role to play, but warned against over-simplifying the problem or relying too heavily on GM crops. A multi-pronged approach is needed, the report said, including further agricultural research and the continuation of local agricultural practices. It also warned that patents on GM technology can have negative effects, such as obstructing independent scientific research and the freedom of small farmers to make their own choices.

In truth, it is wise neither to simply advocate GM technology nor to oppose it entirely.

The technology is already becoming one of the major characteristics of modern agriculture. As it develops, we need independent and objective research, the prompt and full release of information and the participation of all stakeholders.

To discover whether GM crops really can increase yields, we may need to copy the randomised controlled trials that are used in medical research and carry out analysis of actual case studies. Only then will we have a convincing answer.

Li Taige is a Beijing-based journalist. He obtained a master’s degree in engineering from Sichuan University in 1997, and studied as a Knight Science Journalism Fellow at the Massachusetts Institute of Technology (MIT) in 2003-2004.

Homepage photo by CaptPiper

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Default avatar
匿名 | Anonymous

什么基因干什么事

生产的问题,永远是两个问题,一个叫开源,一个叫节流。目前所开发的基因的,抗虫的,抗病的,抗逆境的,都是用于“节流”的基因,拥有这些基因的转基因作物,农民可以减少投入,减少杀虫剂,农药和化肥的施用。这些基因的作用,并不是用来“开源”的,所以在实际农田生产中,如果做为对照的普通作物用药了,施肥了,很可能跟转基因作物相比,在产量上没有区别。我们实验室中强调的,是在同样的环境下,来比较对照和处理之间的区别,显然,在实际生产中,这种同样的环境是很难做到的。张启发教授所发现的基因,很可能是一种“增产”基因,相信在未来,我们能借助它,获得更高的粮食产量。
- Aturen

tailor-made genes for different purposes

The questions that food production has to deal with can be summed up into two categories: one is to increase production, the other is to control crop failure. The genes that scientists are currently researching and developing are either pest resistant, or disease resistant, or stress resistant. They all belong to the latter category. Farming crops with these genes, farmers can reduce their expenditures on pesticide and fertilizer. In practice, however, if pesticide and fertilizer is applied on the comparison group, the output will probably be close to that of the genetically modified group. In theory, comparison should be conducted under the same circumstances, which is obviously difficult to realize in practice. The gene Mr. Zhang qifa has discovered probably has production-enhancing merit. Hopefully we can use it to boost our food production.

Default avatar
匿名 | Anonymous

转基因的初衷

转基因生产的初衷就是增产,提高产量。但是转基因对人的影响还没有充分的数据论证。所以,对转基因技术的评价目前世人莫衷一是。(沅水弯弯)

The initial intention

The initial intention of genetically modified technologies is to increase the yield. However, statistics available right now can not confirm the impact of GM technologies on human beings. Therefore, the value of GM technologies is still controversial.
----Yuan Shui Wan Wan

Default avatar
匿名 | Anonymous

科学真的能拯救人类?

我始终对高端科学持怀疑态度,非自然的东西也许能一时解决我们的眼前之需,但也可能在将来陷人类于地域。中国的天人合一的精神我很赞赏,顺应自然,根据自然规律做出对策才能最终解决问题。

Is science the saviour for human beings?

I have always been sceptical about high-level science. Science might be able to solve our problems in a short term, however, it might also send human beings to hell in the future. I appreciate China’s philosophy of harmony between man and nature. We should comply with Nature, as problems only can be ultimately solved through measures deriving from natural rules.

Default avatar
匿名 | Anonymous

转基因只能破坏大自然

转基因作物推广极可能是打开了潘多拉盒子。

Transgenic Technology Can Only Destroy Nature

Promoting transgenic crops will probably open Pandora's Box.