Drought Tolerant Engineered Crops, But You Can Help Turn the Tide
Doug Gurian-Sherman, UCS senior scientist
The Equation, June 14 2012
http://blog.ucsusa.org/gmo-industry-all-wet-about-drought-tolerant-engineered-crops-but-you-can-help-turn-the-tide
On Tuesday, June 5, UCS released a report, "High and Dry", that analyzes the prospects of genetic engineering to reduce crop losses to drought, and to develop crops that use less water.
http://www.ucsusa.org/food_and_agriculture/science_and_impacts/science/high-and-dry.html
How we deal with losses from drought-the single largest cause of crop loss-and the growing and unsustainable demand for clean fresh water, of which agriculture uses the largest share, are important questions for the coming century. In parts of China, India and the U.S., groundwater sources used to grow our crops are already disappearing or becoming more expensive to tap.
In several articles, industry spokespeople commented about the report. In particular, one spokesperson claimed that Monsanto's new drought tolerant corn, which is evaluated in "High and Dry", uses less water than other corn under severe drought. Another spokesperson commented that we should use all means possible to produce enough food. Do these industry claims hold water?
DroughtGard Does Not Require Less Irrigation
The notion that drought tolerant crops use less water per unit of food than non-tolerant crops is usually not true. More often, according to scientists that work in this field, drought tolerant crop varieties do not use less water. That the identification of drought tolerance with water-use efficiency is a common misconception can be seen in an otherwise solid article about engineered drought tolerant crops in the New York Times from 2008.
The article did a good job discussing the neglected power of breeding to address drought tolerance. It also cited one scientist who discussed conventional drought tolerant corn developed for Africa with 20 to 50 percent improved drought tolerance. At the time, Monsanto claimed its corn would increase yields by 10 percent under drought. We now have preliminary data from Monsanto that DroughtGard improves yields by only about 6 percent in moderate droughts. Or, put another way, DroughtGard has about 10 percent yield loss under moderate drought compared to about 15 percent yield loss for some conventional corn varieties. The article also points out the problem of unintended adverse effects from the engineered gene on other aspects of crop performance (pleiotropy, in genetics jargon). Both of these topics are addressed at length in "High and Dry".
But the NYT article muddies the differences between drought tolerance and water use efficiency, seemingly equating them at several points. It is an understandable error. I was under the same illusion before I did the research for "High and Dry".
Many of agriculture's water problems arise from overuse of river or groundwater sources for irrigation. So it is important for water efficient crops to use less irrigation water and still produce normal yields.
Both high crop productivity and water use efficiency are important goals. The biotech industry often uses the threat of food shortages in coming decadesand claims that it will improve yieldsas important reasons to support biotechnology.
Given that both productivity and water use efficiency are important, it would be undesirable to sacrifice one goal in order to promote the other.
But DroughtGard does not maintain normal yields if irrigation is reduced, according to Monsanto’s data in its petition for deregulation, submitted to USDA. In other words, it’s not more water efficient. The only way for DroughtGard to use less water is to sacrifice yield.
Missing the Point
An industry spokesperson also made the often heard argument that we should use all available means to address the urgent and challenging problems of producing enough food.
But in practice, the technological fixes that the companies push do not foster the use of some of the best means to produce food sustainably. Despite the known benefits of sustainable methods like cover crops and long crop rotations to suppress pests, build soil fertility, increase biodiversity and reduce pollution, these practices are not widely used. The genetic engineering industry wants us to invest in practices that allow it to sell more herbicides or fertilizers, not in improving practices like crop rotations that do not rely on buying more of their products.
Instead of sustainable agriculture, we have increasing reliance on a few crops, which has the opposite effect on the environment. For example corn acreage, driven by higher prices and ethanol mandates, is now at about 96 million acres, about 22 percent higher than a decade ago.
And public sector crop breeding, which can adapt crops to local environments to increase resilience and to better fit in sustainable farming systems, has been neglected. The large majority of competitive grants in the USDA’s Agriculture and Food Research Initiative (AFRI) go to research on genomic methods of breedingwhich, while important, should complement, not exclude, conventional breeding.
One of the main points of our report is that we need to redress the balance between private sector investment in genetic engineeringwhich overall is not solving our problemsand public sector investment in sustainable agriculture that industry is not interested in. These points are ignored by industry spokespeople that have commented on "High and Dry".
What You Can Do Support the Tester Amendment to the Farm Bill
Many groups and scientists are supporting an amendment to the Farm Bill by Senator Jon Tester of Montana-a farmer by trade-that would begin to redress the overemphasis on high-tech methods of crop improvement.
The Tester Amendment would mandate a small set-aside in the USDA research budget for proven, cost-effective classical crop breeding that would produce public-sector crop varieties adapted to local and regional environments and to sustainable farming systems. Crop varieties from the public sector are important, because the large seed companies that now dominate the industry mainly produce engineered cotton, corn and soybeans, and do little to improve other crops in ways that sustainable farming needs.
Contacting your senator in support of this amendment is a step in the right direction, and tells your senator that you support sustainable agriculture. Let's not leave yet another Farm Bill, so important to our food choices and environment, in the hands of special interests.
About the author: Doug Gurian-Sherman is a widely-cited expert on biotechnology and sustainable agriculture. He holds a Ph.D. in plant pathology.
GMO Industry All Wet about