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GM underperformers

Editor's note -- E. Ann Clark, professor of plant agriculture at the University of Guelph in Ontario, wrote the following piece that appeared in the Aug. 14 edition of the Guelph Mercury news in response to an earlier piece in favor of genetically modified crops by farmer Terry Daynard. You'll find a link to Daynard's piece following Clark's commentary. -- RS

by E. Ann Clark
(Thursday, Aug. 21, 2003 -- CropChoice guest commentary) -- I have read with interest the dialogue surrounding the recent Guelph visit of Michael Meacher, former Minister of the Environment in the UK. In response to anecdotal evidence provided by Terry Daynard in "I have sinned: I grow genetically modified crops" (The Guelph Mercury, Aug. 9) on crop performance on his farm, I would offer information from the USDA (Fernandez-Cornejo and McBride, 2002; http://www.ers.usda.gov/publications/aer810/ ), from Charles Benbrook [(1999; http://www.biotech-info.net/RR_yield_drag_98.pdf ) and 2001; http://www.biotech-info.net/troubledtimes.html )] - former Chair of the Board on Agriculture of the US National Academy of Science - and from the scientific literature (Elmore et al., 2002a and b; Agron. J. 93(2):404-407 and 408-412).

Contrary to Dr. Daynard's favorable experience, independent analysts have not found that RR soybeans yield more, reduce herbicide use, or increase farmer profits.

1. Roundup Ready (RR) Soybean Yield. Herbicide-tolerant (HT) crops, of which most are Roundup Ready, account for about two-thirds of all GM crops sown, of which the remainder are Bt (insecticidal) crops. The USDA found that RR soy yields would increase by a scant 0.3%, if 10% of US soybean growers adopted the RR technology. In contrast, a range of industry- , university-, and state-sponsored surveys summarized by Benbrook showed that RR soybean yields averaged 5 to 10% less than conventional soybeans. As shown by Elmore and colleagues, RR soy yield is reduced even more between hand-weeded (unsprayed) lines differing only in the presence of the RR gene. So the yield drag cannot be explained as an artefact caused by the Roundup itself or from comparing genetically different lines. Indeed, because they are not bred for higher yield, the only way that RR crops could ‘increase yield’ would be if other herbicides or approaches proved unequal to the task of suppressing a heavy weed population.

2. Pesticide Use Reduction. USDA researchers reported that RR soy requires more, not less, active ingredient (a.i.) per acre than competing herbicides, many of which are designed to act at very small concentrations. Using typical US tank mixes, herbicide rates on farms range from 0.84 to 2.63 kg a.i./ha for RR soybeans vs. 0.09 to 1.68 kg a.i./ha for conventional cultivars (Table 1.10; Benbrook, 2001). The net effect is that RR soybean growers are now applying about 0.56 kg/ha more herbicide - or 9 million kg more herbicide a year in the US.

While RR soybeans don't reduce herbicide use, they have allowed producers to replace more toxic herbicides with Roundup, which is much less hazardous to human health. However, this benefit is short-lived, because overuse of Roundup on RR-crops has already selected for resistance or tolerance to Roundup in several key weed species, obliging producers to revert to additional herbicides or additional applications of Roundup.

USDA researchers attributed a net reduction of 2.5 million pounds pesticide a.i. to the adoption of GM corn, soy, and cotton crops, primarily due to Bt-cotton in some states. As calculated from ERS-USDA figures (http://www.ers.usda.gov/Data/cropproductionpractices/ShowTables.asp ), total pesticide use on corn, soy, and cotton in 2000 was about 327 million lb. Thus, converting 68% of US soybean acreage to HT soybean, 56% of US cotton acreage to HT cotton, 19% of US corn acreage to Bt corn, and 37% of US cotton acreage to Bt cotton reduced pesticide use by 2.5 of 327 million lb or a barely distinguishable 0.7% in pesticide a.i. The premise that RR soy or Bt corn reduce pesticide use is unsupported.

3. Bt-Corn. The reference to the Wilson farm market study assessing preference for Bt- vs. non-GM sweet corn warrants elaboration. The reader is referred to Chapter 4 of a new text by Stuart Laidlaw of the Toronto Star, entitled Secret Ingredients. The tenor of the trial, which was run by Doug Powell, a risk communicator at the University of Guelph, is reflected in a photo taken at the Wilson farm market (p.89). Above the non-GM sweet corn bin is a sign: “Would You Eat Wormy Sweet Corn? Regular Sweet Corn: insecticides: carbofuran sprayed 3X or Bt foliar spray sprayed 1X; Fungicide: Bravo sprayed once; Herbicide and Fertilizer: 1 application of each”. In contrast, the Bt-sweet corn bin was labeled: "Here’s What Went into Producing Quality Sweet Corn”, followed by a list of fertilizers, with the fact that it was Bt-corn shown on a separate sign. Given the clear experimental bias introduced by the label wording, Laidlaw's key finding was that consumers were nonetheless willing to buy 5000 cobs of "wormy" (vs. 8000 cobs of "quality") sweet corn - clearly indicating consumer distrust of, rather than preference for, Bt sweet corn.

4. Net Returns to Farmers. USDA researchers (p.24) stated: APerhaps the biggest issue raised by these results is how to explain the rapid adoption of GE (GM) crops when farm financial impacts appear to be mixed or even negative...Even more puzzling, the adoption of herbicide-tolerant soybeans and Bt corn has been rapid, even though we could not find positive financial impacts in either the field-level nor the whole farm analysis. This does not mean that returns are always unfavorable, as shown by Dr. Daynard's testimonial, but on average, GM corn and soybean have not paid for US farmers. In comparing the economic returns from Bt corn between 1996 and 2001, Benbrook ( http://www.biotech-info.net/GMO_corn.pdf) ) calculated that US farmers paid at least $659 million in price premia to grow Bt corn, but returned just $567 million, for a net loss of $92 million.

Likewise, Furtan et al. (2003; http://www.usask.ca/agriculture/agec/research/publications/working_papers/biotech_lemon.pdf ) found that the proposed introduction of RR wheat in Canada would entail losses of $45.8 and $32.3 million annually to the adopters and non-adopters of the technology, respectively, while bringing in a positive $156.6 million to Monsanto. Farmers lose because 82% of those who import Canadian wheat say they won't accept GM wheat, and it is not feasible to segregate them. Because the price of GM-contaminated wheat is less, everybody loses except Monsanto.

5. Why Do Farmers Continue to Buy GM Seed? If GM crops do not perform as promised, then why do farmers continue to buy the seed, and specifically the GM canola which so disturbed Meacher? Understanding that HT and mostly RR canola accounts for all the GM canola sold in western Canada, several reasons could be offered: 1) To make weed control more convenient, as suggested by the USDA researchers. This is particularly plausible where ecologically unsound crop management practices have produced a large population of intractable weeds; 2) To avoid the risk of a lawsuit. Percy Schmeiser, a 72-year-old Saskatchewan canola grower, was found guilty of patent infringement when Monsanto's RR gene was found in his canola, despite the fact that the contamination was inadvertent, that he didn't benefit from it, and that he couldn't have avoided it. His case, which has already cost hundreds of thousands of dollars, will be heard by the Supreme Court of Canada in January 2004; 3) To access other desired traits, The same seed companies which offer GM cultivars also control the seed supply of non-GM cultivars. Seed of the best varieties may be of limited supply, unless fitted with a GM trait; or 4) To deal with the problem of contamination in non-GM seed. Seed companies no longer guarantee that non-GM seed is actually GM free, for the same reasons that Schmeiser's fields were contaminated. In fact, considerable evidence has shown that the non-GM canola seed supply is already contaminated. Thus, buying GM seed which allows the spraying of Roundup may be the only agronomically sound alternative to buying non-GM seed and then having to apply additional sprays to cope with in-crop Roundup tolerant canola volunteers.

In sum, the concerns expressed by Michael Meacher about the impact of GM technology on Canadian farmers are fully supported by authoritative evidence from the USDA and others. Canadian data was not cited because comparable analyses have not been forthcoming from the Canadian government. The many promises made for GM crops have not withstood the test of time. Instead, GM crops have served to enrich biotech companies at the expense of financially strapped farmers, expose non-adopters of GM to the unavoidable risk of lawsuits, eliminate organic canola growing in the west, contaminate the food supply with GM crops that consumers don’t want, and compromise the marketability of our crops to off-shore buyers. Since when do consumers have to buy something just because we want to grow it? Enough is enough. The government of Canada needs to rethink its unqualified support for this underperforming and unwanted technology.

You can find Terry Daynard's piece, 'Farmer: I have sinned. I grow GM crops,' at http://www.cropchoice.com/leadstry.asp?recid=1954

E. Ann Clark's website: http://www.plant.uoguelph.ca/research/homepages/eclark/