By Rolf Penner
(The Following originally appeared in the Winnipeg Free Press.)
If tolerance levels are reasonable, cross-pollination not a danger
In a recent free press article, Interlake sheep rancher Peter Schroedter wrote about the perils of genetically modified (GM) wheat to prairie farmers.
His biggest bone of contention was segregation. Opponents of GM wheat want a 100% guarantee that this new wheat will not cross-pollinate with existing varieties, they wish to insure widespread ‘genetic purity’. This is quite a request since no one has ever been able to achieve ‘genetic purity’ on a commercial scale before. Even the organic industry won’t give you a 100% guarantee on the content of their products; what they guarantee is a process with reasonable tolerance levels. For example in pesticide residues, organic standards in the United States allow for 5% of the EPA tolerance levels.
That’s not to say that genetic purity is impossible, plant breeders attain it all the time in their labs and by situating their plots in the center of large tracts of land surrounded by buffer crops and following various protocols. But they don’t do it by holding their neighbors responsible for their own bio-security.
For the first time in history people are actually worried about wheat contaminating wheat. Which is absolutely absurd. The difference today is not that we have put manmade characteristics in the wheat; we have been doing that for generations now. It’s that we have now figured out how to track them.
Unrealistic
Maintaining 100% genetic purity is not realistic, the real question is what level of genetic transfer might we expect to see and would that level be acceptable? This varies from plant to plant and from variety to variety within a plant species. Self-pollinating plants like wheat and soybeans have a much lower level of transfer than cross-pollinating plants such as canola or corn because after a relatively short distance the pollen actually dies. The university of Southern Illinois weed science department recently did a study on GM soybeans, which showed that after a distance of 2 feet 100% of the pollen had perished. Australian researchers whose work was published in the July 2002 Science Journal showed that canola pollen containing a herbicide resistant gene could be found up to 2.6 kilometers from the source. However from samples taken all the way out to 2.6km. the average number of seeds that actually carried the new gene was 9 in 100,000 or .0009%. The single sample containing the highest level of seeds with the genes was 7 in 10,000 or .07%. It’s not unrealistic to expect similar kinds of results from wheat. Which is way below the standards that even the radically anti-GM European union currently sets at 1%.
This is one reason why farmers such as myself have been able to easily sell non-GM canola with and without identity-preserved programs while there has been an ever-increasing amount of GM canola (70% this year) being planted. It’s not that GM canola is absent in every field, but that it is present in such extremely low concentrations as to be inconsequential to the final product.
The modern high-tech farmer increases his odds of being GM free by simply rotating his herbicides or growing a ‘Clearfield’ variety. These are varieties that have been bred in the traditional way but are resistant to a broad-spectrum herbicide that can easily kill GM glyphosate tolerant canola. As I was writing this article the first ever ‘Clearfield’ wheat variety was registered for use in western Canada, it will be available to farmers in 2004.
Then there’s the identity-preserved route. Which is a closed loop system requiring farmer’s to not have grown any GM canola in the last three years, and then buy clean certified seed from the same company that they will eventually sell their final crop to. And the farmer must maintain at least a 25 metre buffer crop or zone from any GM canola.
Tried and True
Then there are the tried and true low-tech strategies, which include things like: rotating your crops, tillage before seeding and just talking to your neighbors to see when they are planting their crops. A mere 5-day difference in seeding dates insures that neighboring crops will pollinate at separate times.
When any combination of these strategy’s and systems are used they do not add any kind of significant cost to the farmer, as the opponents of GM wheat would have us believe, they are simply a continuation of what farmers have always done.
Then there’s the question of segregation in the supply chain. We have been doing it for a few years now in canola but can we do it on a large scale with wheat? At a recent Sask-Pool meeting in Winnipeg this question was raised and a representative replied that not only would segregation be possible but also that they would probably be able to make money on it.
So can GM wheat and non-GM wheat co-exist? In a zero tolerance world that is able to detect variations down to 4 decimal points the answer is no, but if tolerance levels are acceptable at1% or less, absolutely.
Rolf Penner is a Grain and Hog farmer in the RM of Morris.
