1.Will Genetic Engineering Divert Us from Essential Food Production Science?
2.Engineered Pest Problems

NOTE: The Union of Concerned Scientists has started a new blog covering all of the issues they work on. Several scientists and analysts that work on food and agriculture issues are part of this effort. The blog is located at: http://blog.ucsusa.org

Below are two blog posts by UCS's Doug Gurian-Sherman, responding to Nina Fedoroff's recent op-ed in the New York Times extolling genetically engineered crops, and on the recent discovery of corn rootworms resistant to Bt corn.

Dr Gurian-Sherman is a widely-cited expert on biotech and sustainable agriculture. He holds a Ph.D. in plant pathology. He also has an intimate knowledge of the US regulatory system on GM crops, having been a biotech specialist at the EPA and an advisor to the FDA.

His original blog posts contain a number of embedded links that are not reproduced here.
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1.Will Genetic Engineering Divert Us from Essential Food Production Science?
Doug Gurian-Sherman, senior scientist, Food and Environment
The Equation, August 29 2011
A blog on independent science + practical solutions
http://blog.ucsusa.org/will-genetic-engineering-divert-us-from-essential-food-production-science

Climate change, increasing population, greater demand for animal products, and the un-sustainability of current food production: All will challenge our ability to produce enough food in coming decades. Already there is evidence that climate change has reduced crop yields.

But the good news is that we already have many of the tools that we need to respond.

Tom Philpott at Mother Jones highlights a peer-reviewed article showing that small Mexican maize farmers have an important piece of the answer to these challenges.

The article suggests that there is a lot of genetic diversity in corn grown on traditional small Mexican farms that will allow food production there to adapt to climate change. Genetic diversity provides the building blocks of crop adaptability-the inherited differences between plants that is evolution’s way of allowing survival in changing environments.

The value of crop genetic diversity goes way beyond Mexican maize fields. Other scientists have documented  large amounts of untapped genetic diversity in the world’s major crops wherever they have looked, such as in wheat and cassava. Breeders can use this, along with diversity found in wild species related to crops, to adapt our crops to climate change and to increase productivity.

When coupled with ecological farming principles that increase resilience in the face of drought, flood and rising temperatures, breeding can go a long way toward providing enough food sustainably by mid-century. For example, organic and similar practices build soil organic matter this allows soil to hold more water which can help during drought. And breeding is already having success in developing drought tolerant rice,  corn, and other crops, flood tolerant rice, many types of pest resistance, improved nutrient content, and much more.

Engineered Omissions

Given all the evidence, it is perplexing that some scientists still want to put too many of our eggs in the genetic engineering (GE) basket.  Currently, that basket looks pretty empty, with only a few crops resistant to herbicides and a few types of pests.

For example,  Nina Fedoroff seems unaware of the potential of breeding, and the advances already being achieved through these scientifically sophisticated methods. In an op-ed in the New York Times, “Engineering Food for All” the former Bush-appointed Science Adviser to the Secretary of State lauds the wonders of crop genetic engineering, while tagging breeding as an “older” method that is “less capable”.

In a more blunt assessment during a public forum that I participated in at Dartmouth College several months ago, Fedoroff declared that crop breeding had run its course, and implied that GE was now our last best hope.  She could not have been more wrong. The only way one can come to such conclusions is by omitting or overlooking loads of important science.

Most of the benefits from GE extolled in the op-ed are modest at best. They only seem impressive if you don’t compare them to the successes and potential of agroecology, agronomy, or breeding-which continue to achieve far more than GE. When looked at side-by-side, GE often pales by comparison to breeding.

Take drought tolerance for example. While a number of drought tolerant crops have been developed in recent years through breeding with more to come the first modest GE version is at least a year or two away. In the U.S., where GE crops have to compete with advanced agricultural methods, the yield increases from engineered genes have been much less than from breeding and improved crop management. If not for the latter methods, and had we relied only on GE instead, overall corn yields in the U.S., the biggest global exporter, would probably be about 25 percent less than they are. Yield of soy, our second biggest crop, would be about 16 percent less.

And for poor farmers in developing countries, methods based on sophisticated ecological principles can far outpace the gains from GE, as pointed out by author Anna Lappé at Civil Eats in her response to the op-ed.

Even where a particular advantage is claimed for GE, the op-ed is often misinformed. Engineered insect-resistance reduces harmful mycotoxins that occur in some corn kernels-an unanticipated bonus. But here too, breeding is showing up its engineered counterparts. Federoff claims that insect-resistant corn prevents fungi, and hence mycotoxins, from contaminating corn. She is only half right. It reduces only one type of mycotoxin, called fumonisin. That’s a good thing. But GE insect-resistant corn does nothing to prevent an even more serious cancer-causing mycotoxin called aflatoxin, caused by other types of fungi. By contrast, conventional breeding, in the hands of the U.S. Department of Agriculture, has recently produced corn that so far shows resistance to both fumonisin and aflatoxin.

The attractiveness and need for GE depends in part on how it stacks up against other agricultural methods and technologies. So far, and for the foreseeable future, breeding and ecologically-based farming will be considerably more effective and cost less. Genetic engineering can have a role if properly regulated, but focusing on it myopically threatens to distract us from supporting better technologies.

[Fedoroff’s assessment of the risks and regulation of GE is also off base-I'll address that in my next post.]
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2.Engineered Pest Problems
Doug Gurian-Sherman, senior scientist, Food and Environment
The Equation, August 30 2011
A blog on independent science + practical solutions
http://blog.ucsusa.org/engineered-pest-problems

Genetically engineered crops contain combinations of two widely successful types of genes-glyphosate herbicide resistance that allows spraying the weed killer onto crops without harming them, and toxins, collectively called Bt, that kill some insect pests. Both are now facing problems that are threatening their usefulness. Weeds that have developed resistance to glyphosate are no longer controlled by the herbicide, and now infest millions of acres of cotton and soybeans in the U.S, causing substantial practical, economic, and environmental problems.

The GE industry's solution is to engineer new types of herbicide-resistant crops. But because there are no widely-effective new herbicides, these new crops will be resistant to older, riskier herbicides like 2, 4-D and dicamba, that were some of the first commercial pesticides.

This does not strike me as a new and innovative approach to agriculture for the 21st century.

Now we have the first report of lost effectiveness of one of the two major types of Bt used in corn. This type of Bt, technically called Cry3Bb1, usually kills corn rootworm. Corn rootworm is one of the most destructive insect pests of corn, and more insecticide was used to control it than for any other corn insect pest in the U.S.

The rootworm report follows recent reports of other insects developing resistance to other Bts in cotton in India and corn in South Africa.

So far the resistant rootworms have been found at only a small number of sites in Iowa and Illinois. But unless strong measures are taken to reverse the practices that have led to it, these incidents will be only the beginning.

A recent article by Scott Kilman in the Wall Street Journal covers this issue well, but leaves out some important points.

One is that biotechnology does nothing to encourage ecologically sound agriculture that would address these problems in the innovative and effective ways that are needed. Instead, the industry and many of its supporters have been advocating actions-such as weakening an already limited regulatory system for GE-that could exacerbate these problems.

Regulatory Discretion-or Capitulation?

Not mentioned in Kilman’s article was that EPA invited a group of scientists to provide recommendations about how to prevent rootworm resistance to Bt corn. Instead of following the majority opinion to require strong measures to prevent resistance,  EPA instead listened to the minority of less-cautious scientists and the interests of the biotech industry, and went with a weaker approach. We may be seeing the results of this shortsighted action in the new resistant rootworms.

There are two other types of Bt that still control the new Cry3Bb1-resistant rootworm. But they all share a property that generally makes them vulnerable to resistance: none are effective enough to kill almost all rootworms. The surviving rootworms increase the chance that rare Bt resistance genes will be able to spread. So greater use of the other main Bt, called Cry34/35Ab1, to replace Cry3Bb1 will increase the chance of causing its own resistance crisis before too long. Cry34/35Ab1 was approved several years after Cry3Bb1, so it may take a little time to catch up!

And if entomologists think that farmers, en masse (which is what it takes) will give up products that work well in order to prevent resistance, they should look closely at what has happened with glyphosate resistant weeds. The kinds of practices that could have forestalled resistance have long been known, but instead of using them, we now have millions of infested acres.

If EPA does not use its regulatory authority to do what is needed, history tells us the resistance problem is likely to get much worse.

Kilman mentions a new type of GE called RNA interference (or RNAi for short) for killing pest insects, that may come to the rescue. RNAi shows some promise, but there are lots of hurdles for a new technology like this before it can be successful commercially. It will be years, at least, before it is available to farmers.

And there is no reason to believe that RNAi would not also face resistance problems.

Kilman is apparently not aware of several promising non-GE rootworm-resistant varieties of corn recently developed through conventional breeding by USDA and universities. Funny that we don’t hear about them they are likely farther along than RNAi. If they are successful, they will be yet another example of conventional breeding matching or exceeding GE.

The issues surrounding pest resistance reveal an agriculture sector with serious problems, despite its high productivity, that need serious solutions.

A Fundamentally Different Agriculture is Needed

Relying on genetic approaches alone to control pests-even conventional breeding-leaves crops vulnerable to numerous problems. We also need to use ecologically sound farming practices that complement genetics.

Briefly mentioned in the WSJ article is the fact that rootworm is not much of a problem if sensible crop rotations are used. Crop rotation is the alternating of the types crops that are planted from year to year, and is a fundamental part of organic farming. Instead most farmers in the Midwest grow nothing but corn or soybeans year after year.

Put another way, rootworm probably would not even be an important pest if it were not for our unnecessary over-dependence on corn.

And long crop rotations reduce more than rootworm damage. They greatly reduce most pests, including other insects, diseases, and weeds, thereby greatly reducing pesticide use as well. Long crop rotations also improve soil fertility, and reduce fertilizer use, cost and pollution. And they can be just as productive as our current corn obsession.

So why aren’t we using them?    Part of the reason is that current policies such as ethanol supports and other subsidies favor corn and a few other crops, and exclude others that could be grown in rotation. And without better government policies-like shifting incentives to support good farming practices-farmers will usually  go for the easiest and cheapest ways to grow their crops. Who can blame them?

But isn’t this what we used to call shortsighted?