Tuesday, November 11, 2014

A Meta-Analysis of the Impacts of Genetically Modified Crops

"We carry out a meta-analysis of the agronomic and economic impacts of GM crops to consolidate the evidence....... 
"On average, GM technology adoption has reduced chemical pesticide use by 37%, increased crop yields by 22%, and increased farmer profits by 68%. Yield gains and pesticide reductions are larger for insect-resistant crops than for herbicide-tolerant crops. Yield and profit gains are higher in developing countries than in developed countries......... 
"The meta-analysis reveals robust evidence of GM crop benefits for farmers in developed and developing countries. Such evidence may help to gradually increase public trust in this technology."
Wilhelm Klümper and  Matin Qaim, PLOS ONE, November 3,2014
This is an in depth confirmation of the value of biotechnology applied to the development of improved crop varieties and agronomic practices. The scientific article is summarized in an article in The Economist. I quote also from that article:
Commercial genetic modification for crops comes in two forms. One makes them resistant to insect pests. The other confers tolerance to glyphosate, enabling farmers to spray their fields with this herbicide and kill off all the other plants (ie, the weeds) in them. As a consequence, the study found, herbicide-tolerant crops have lower production costs—though this was not true for insect-resistant crops, where the need for less pesticide was offset by higher seed prices, and overall production costs were thus about the same as for unmodified crops. With both forms of modification, however, the yield rise was so great (9% above non-GM crops for herbicide tolerance and 25% above for insect resistance) that farmers who adopted GM crops made 69% higher profits than those who did not. 
Many poor countries eschew GM crops, fearing they will not able to export them to areas which ban them, notably the European Union. This has a big opportunity cost. Dr Qaim and Dr Klümper found that GM crops do even better in poor countries than in rich ones. Farmers in developing nations who use the technology achieve yields 14 percentage points above those of GM farmers in the rich world. Pests and weeds are a bigger problem in poor countries, so GM confers bigger benefits.
Genetically modified crops, that is crops using cultivars that have had genes introduced by modern methods from biotechnology, have been used for more than two decades. To the best of my knowledge the regulatory methods to assure their biosafety have worked and there have been no health problems associated with the GM crops that are not also found with traditional crops; indeed they are probably safer. The research, as demonstrated by the meta analysis cited above, indicates that they produce more food and feed from the farmers fields and increase farmers incomes. Perhaps we need to reduce the fear that a portion of the public feels about these crops.

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