Tuesday, July 17, 2012

The Failure of Genetic Engineering

There's a steady drumbeat that we are not producing enough food, that there must be more food for the growing global population, and that traditional or organic agriculture cannot achieve the necessary volumes. Therefore, continues the argument, we need to shift all our production over to genetically engineered varieties which produce more food per acre than traditional farming techniques. And its a compelling argument. Global population at six billion and due to rise to at least nine billion. Famine conditions popping up all over the place. The future looks grim. Perhaps we should embrace a technological fix.
Just two small problems. Tiny, really. First, The genetically engineered plants we grow aren't really food. The corn and soy we grow are not intended as food, not like, say, a carrot is food. Let's call them “precursor foods”; they are feed-stocks we tear apart into their constituent molecules and then construct “edible food-like products” from them.
And the second problem is just as minor. There's no evidence. At all, really. Down in the United States, the Union of Concerned Scientists (UCS) sponsored a report on production differences between traditionally bred crops and genetically engineered ones, a report written by Doug Gurion-Sherman, a senior scientist in the UCS Food and Environment Program. His conclusions?

Thus a close examination of numerous studies of corn and soybean crop yields since the early 1990s gives us a good gauge of how well GE crops are living up to their promise for increasing yields. Bottom line; They are largely failing to do so. GE soybeans have not increased yields, and GE corn has increased yield only marginally on a crop-wide basis. Overall, corn and soybean yields have risen substantially over the last 15 years, but largely not as a result of the GE traits. Most of the gains are due to traditional breeding or improvement of other agricultural practices.1

This is not a minor matter. GE crops are touted as saviour seeds for farmers, for hungry populations, for the world. They are, in fact, the final development of the the Green Revolution, the ultimate expression of the technologization of agriculture. And, like the Green Revolution, not only have they largely failed, but the original goals have been forgotten in a rush to manufacture profit and privatize life. The findings of the report are clear and powerful. First, that

“[g]enetic engineering has not increased intrinsic yield. No currently available transgenic varieties enhance the intrinsic yield of any crops. The intrinsic yields of corn and soybeans did rise during the twentieth century, bu not as a result of GE traits. Rather, they were due to successes in traditional breeding.”2

Intrinsic, or potential, yield is the highest yield that can be achieved under perfect conditions. This is different from operational yield, the yield obtained under field conditions. About which, the report says:

Genetic engineering has delivered only minimal gains in operational yield.... Based on available data, it is likely that Bt corn provides an operational yield advantage of 7-12 percent compared to typical conventional practices, including insecticide use, when European corn borer infestations are high. Bt corn offers little or no advantage when infestations of European corn borer are low to moderate, even when compared to conventional corn not treated with insecticides.3 [emphasis mine]

The increases we've seen in yields in corn and soy are, primarily, attributable to non-GE plant breeding techniques. The development of salt-tolerant wheat, for example, was done by crop scientists in Australia specifically without the use of GE techniques, in order to ensure free access to the cultivar by the world's farmers.
The report even takes the time to point out that:

Organic and low-external-input methods (which use reduced amounts of fertilizer and pesticides compared to typical industrial crop production) generally produce yields comparable to those of conventional [here the word “conventional” refers to industrial style production] methods for growing corn or soybeans....Also, more extensive crop rotations, using a larger number of crops and longer rotations than current ecologically unsound corn-soybean rotations, can reduce losses from insects and other pests.4

The comment, above, about “current ecologically unsound corn-soybean rotations” is because of a management practise common in North America; rotating fields between soybeans and corn in order to reduce infestations of European corn borer. But the corn borer has adapted, and now can be found laying its eggs in fields of soy, having discovered that the odds are good that the next year the field would be rotated back to corn. The report also looked at GE crop trials, breaking them down into groups like “pest resistance”, “disease resistance”, and “improved yield”. Having done so, and taking into account the secrecy surrounding the trials and traits being tested, Gurion-Sherman concludes “[e]xperimental high-yield genetically engineered crops have not succeeded”. In fact:

[T]he only transgenic food/feed crops that have been showing significantly improved yield are varieties of Bt corn, and they have contributed gains in operational yield that were consideralby less over their 13 years than other methods of increasing yield....Most of the trans-genes being considered for the future, unlike the ones in currently commercialized transgenic crops, influence many other genes, thereby resulting in more complex genetic effects. Such genes typically have multiple effects on a crop, and early research is confirming that some of these effects can be detrimental, maybe even preventing the crops' commercialization altogether.5

And the thing is, there is a proven way of increasing actual food yields on farms. Field tested in South America, Cuba, and Africa, agro-ecological techniques have shown up in production increases—increases ranging from 40 to 200 percent, with increases of 100 percent not being uncommon. Add to that the inverse size-yield relationship (where the smaller the farm, the greater the caloric production) detailed by Fatma Gül Ünal in the Small is Beautiful paper, and it becomes clear that if we want to raise yields, if we want to raise yields of foods rather than feed-stocks, and if we want to avoid the ongoing “slummification” of the planet, (as Mike Davis details), we don't need GE seeds or industrial farming. What we need is smaller farms, mixed farms, farmer-directed research, and more people farming.

1: D. Gurion-Sherman Failure to Yield: evaluating the performance of genetically engineered crops April 2009, UCS Publications, Cambridge, MA
2: ibid p. 2
3: ibid p. 2
4: ibid p. 3
5: ibid p. 4

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