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GM crops are not the answer to world hunger

Last week, chinadialogue columnist Taige Li explored whether genetic modification can increase crop yields. Emma Hockridge responds, and argues that oil-intensive biotechnology will not ease the global food crisis.
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With soaring food prices around the world, there has been a renewed recent interest in whether the world can feed itself. This question is not a new one, and many organisations have been talking about the need to radically change our food and farming system to one which is more sustainable for many years.

The current industrial agricultural system, which has been in place for around 60 years, is wholly reliant on oil- and gas-intensive inputs such as fertilisers and pesticides.

The recent spate of media attention has given the pro-genetic modification (GM) lobby an opportunity to hijack the debate and attempt to persuade people that there is some mileage in this outdated debate. Although the GM industry has been promising huge benefits as a result of this technology for many years, the truth is that none of these claimed benefits have come to fruition. GM crops do not produce higher yields, use fewer pesticides, or do anything to assist people in developing countries.

It is obviously upsetting for the GM industry – and others who have a blind faith in the capacity of complex, high-tech solutions to solve every problem – to have their beliefs challenged by reality. This is what has happened to true believers in GM crops. Out in the fields of North America, while GM crops resistant to sprays or capable of killing insects have made life simpler for big farmers, they have not – according to the US department of agriculture – increased yields. In farmer’s fields in India, GM crops have not increased yields and have sometimes failed – with catastrophic consequences.

The recent International Assessment of Agricultural Knowledge, Science and Technology for Development (IAASTD) report, with input from hundreds of scientists from all over the world, recognises that the challenges farming now faces are those of the increasing scarcity and price of oil and the need to cut greenhouse-gas emissions from farming (primarily nitrous oxide) by 80% by 2050. As with energy production, the future of food production lies in systems which take nitrogen from the air to fertilise crops using energy from the Sun, as with organic farming, rather than burning up increasingly scarce oil and natural gas. Peer-reviewed scientific research continues to show that these sustainable farming systems will increase food production in developing counties, and will provide us with slightly more food than we currently produce. 

With specific regard to the question of yields, all major GM crop varieties in cultivation have produced yields that are lower than, or at best, equivalent to, those of non-GM varieties. The Soil Association has published a briefing on the latest available research on GM crop yields from the past ten years.
The research on GM crops as a whole shows that first-generation genetic modifications address production conditions (insect and weed control), and are in no way intended to increase the intrinsic yield capacity of the plant.

For example, an April 2006 report from the United States Department of Agriculture (USDA) states that “currently available GM crops do not increase the yield potential of a hybrid variety. […] In fact, yield may even decrease if the varieties used to carry the herbicide tolerant or insect-resistant genes are not the highest yielding cultivars”. The United Nations Food and Agriculture Organization’s 2004 report on agricultural biotechnology acknowledges that GM crops can have reduced yields. A 2003 report in Science by Matin Qaim and David Zilbermann – both strong supporters of GM crops – stated that: “in the United States and Argentina, average yield effects [of GM crops] are negligible and in some cases even slightly negative.”

For the three crops which are being produced using GM technology, the individual results are just as bleak. Studies from 1999 to 2007 consistently show Monsanto's Roundup Ready (RR) GM soya to have 4% to 12% lower yields than conventional varieties. Yields of GM soybeans are especially low under drought conditions. Due to pleiotropic effects, when stems split under high temperatures and water stress, GM soybeans suffer 25% higher losses than conventional soybeans. The “yield drag” – or yield suppression – of RR soya is reflected in flat overall soybean yields from 1995 to 2003, the very years in which GM soya adoption went from 0% to 81% of US soybean acreage. By one estimate, stagnating soybean yields in the US cost soybean farmers US$1.28 billion in lost revenues from1995 to 2003.

Only maize shows a persistent trend of yield increase into the biotech era, but even here the rate of increase is no greater after than before biotech varieties were introduced. For example, a rigorous, independent study conducted in the US under controlled conditions demonstrated that Bt maize (see “Is GM the answer to the food crisis”, Taige Li) yields anywhere from 12% less to the same as very similar conventional varieties.

Despite claims of increased yield, Bt cotton has had no significant impact in real terms. Average cotton yields have increased fivefold since 1930, and staged an impressive surge from1980 to the early 1990s. Cotton yields then went flat, and continued to stagnate during the seven years of GM cotton’s rise to dominance. The steep yield and production increases in 2004 and 2005 were chiefly attributable to excellent weather conditions. Outbreaks of the secondary pests that are not killed by the Bt insecticide have rendered Bt cotton ineffective in China and are also becoming a problem in the American states of North Carolina and Georgia.

The debate over GM crops has now moved on: GM chemical companies claim they have the answer to world hunger while selling products which have never led to overall increases in production – and which have sometimes decreased yields or even led to crop failures. As oil becomes scarcer and more expensive, we need to move away from oil-dependent GM crops to producing food sustainably with renewable energy, as is the case with organic farming.


Emma Hockridge works for the policy department at the Soil Assocation

Homepage photo source: USDA


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Default avatar
匿名 | Anonymous


- Aturen

Two Types of Agriculture

As industry is divided into labor-intensive industry and skill-intensive industry, agriculture has the same classification as industry. The counterpart of skill-intensive industry in agriculture probably refers to “oil-gas intensive agriculture” raised by Ms. Hockridge. The so-called “oil-gas intensive agriculture” mainly exists in developed countries. Now in developed countries, hunger is not a problem any more. And the technology of genetically modification is mainly researched in developed countries. Thus, the genetically modified crops are not for the purpose of solving hunger, but for “cleaner and better” food for people. So the result is just the same as my previous conclusion: genetically modified crops cannot solve the problem of output. Moreover, I have to add one point here, genetically modified crops do have the possibility of decreasing output, for the extra ability of insect resistance and stress tolerance need more energy to develop, although the portion of energy maybe little. Besides, I haven’t completely understood why genetically modified crops are relying on oil. I agree on this opinion although I don’t agree with the proof that the author provided. Genetically modified crops cannot solve the hunger problem in developing countries and that’s for sure, because technology is just a method of solving problem of nature, not the human problems—hunger and pollution. Human being’s own problems can only be solved by our methods—politic and economic. If human don't restrict his own behaviors and keep incongruence economic, great technology cannot meet our desire. Actually, food in the world is not insufficient. The poor don't have enough food because the rich buy too much. --Aturen

Default avatar
匿名 | Anonymous

Re: Aturen

转基因农业基本仍然走的是石化农业的老路,说它依赖石油我想是因为它们仍需倚赖化肥。而对于那些广泛种植的抗除草剂品种(如孟山都公司的Roundup Ready大豆),除草剂的使用量也仍然惊人。这也是石化产品的衍生产物。另外,大规模单一化种植对机械的要求也间接要求石油的供应。
-- TVhead

Respond to Aturen’s comment

GM agriculture follows the old oil-intensive path. It is oil reliant because it still relies on fertilizer. As for the widely planted pesticide resistant species, such as Monsanto’s Roundup Ready soybean, the amount of weed killers used is staggering, which is also a by-product of petro-chemical industry. Furthermore, the use of agricultural machinery for large scale single cropping cannot do without oil. TVhead

Default avatar
匿名 | Anonymous

Re: TVhead


Response to TVhead

Urea is probably the only fertilizer that relies on oil, and it is just one of nitrogen fertilizers. Hence it is exaggerated to say fertilizers rely on oil. I do not understand what kind of agriculture those environmental politicians want. Mechanization and fertilizer represent the progress of agriculture. Even so, agriculture consumes little energy compared with industries. It is impossible to popularize the so-called organic agriculture which claim to be fertilizer-free, because high-yield fields are quite limited. As for the pesticide-resistant species you have mentioned, we can try to reduce the amount of weed killer used, but the idea of abandoning weed killer is unreasonable. Total abandonment will not benefit current ecological balance. In addition, if we forbid all weed killers, the only alternative is to pluck the weeds by hand. It is impossible except in labor-intensive agriculture.