There was interesting debate in the GMO arena lately that has triggered some thoughts of my own (always a surprising result). While the argument was almost pro forma - "GMO's are bad!", "No, they're not!" - the research in question has some implications for the corn yield curve.
It all began when a researcher for the Union of Concerned Scientists reviewed available research on GMO's and yields. Now I know the UCS is not wildly popular with farmers, but actually wading through the report did produce a new question in my mind.
The basic point the author was asserting was GMO's have failed to live up to the hype about raising yields since a strong argument can be made any contribution to how the plant actually makes grain, for example is small compared to the effect of protecting the plant from pests.
The biotechnology industry has been promising better yields since the mid-1990s, but Failure to Yield documents that the industry has been carrying out gene field trials to increase yields for 20 years without significant results.Much of this rang true with my on-farm experience. While most farmers have been excited about corn yields, when you pin them down, part of the thrill was comparing to flat bean yields.
Failure to Yield makes a critical distinction between potential—or intrinsic—yield and operational yield, concepts that are often conflated by the industry and misunderstood by others. Intrinsic yield refers to a crop’s ultimate production potential under the best possible conditions. Operational yield refers to production levels after losses due to pests, drought and other environmental factors.
The study reviewed the intrinsic and operational yield achievements of the three most common genetically altered food and feed crops in the United States: herbicide-tolerant soybeans, herbicide-tolerant corn, and insect-resistant corn (known as Bt corn, after the bacterium Bacillus thuringiensis, whose genes enable the corn to resist several kinds of insects).
Herbicide-tolerant soybeans, herbicide-tolerant corn, and Bt corn have failed to increase intrinsic yields, the report found. Herbicide-tolerant soybeans and herbicide-tolerant corn also have failed to increase operational yields, compared with conventional methods.
Meanwhile, the report found that Bt corn likely provides a marginal operational yield advantage of 3 to 4 percent over typical conventional practices. Since Bt corn became commercially available in 1996, its yield advantage averages out to a 0.2 to 0.3 percent yield increase per year. To put that figure in context, overall U.S. corn yields over the last several decades have annually averaged an increase of approximately one percent, which is considerably more than what Bt traits have provided. [More]
Furthermore, for much of the Corn Belt, it is possible that better rootworm/corn borer protections and less setback from herbicides could account for the recent jump in yield, just as UCS alleges.
What this does not suggest to me is GM crops have "failed". But it does raise some interesting questions about how much more bang we can expect from new traits. After all, you only get the herbicide/insect protection boost once.
The UCS report, was sharply criticized by a writer who work I admire, Ron Bailey, and Dr. Wayne Parrot. Both raise logical points against the conclusion GM crops have not delivered the goods. (Great summary of the debate here). But neither answers the buried question that holds my interest: are GM yield increases largely a one-time shot, with subsequent progress more likely to emerge from conventional breeding techniques?
This lack of refutation of this key point is suggestive at least of informal conversations I have had with corn breeders. Germplasm is still where it's at IMHO, and simply cramming traits into any old line may be a short-term answer.
I grow a lot of non-GMO corn for a premium, and my yield curve, while not as impressive as my neighbors, is going the right direction at least. It remains to be seen if intrinsic yields can be proven to be lifted like operational yields at this point.
To be sure, yield is yield. Most of us don't really care where those bushels come from. Swallowing predictions of even larger increases (and paying super-premium seed prices) is another thing altogether. As Illinois researchers have pointed out, changing the trendline slope for corn yields is not proven yet.
How can we reconcile the lack of evidence for an increase in corn trend yields with the widespread perception that trend yields accelerated over the last decade? One possibility is that observers failed to recognize the impact of relatively favorable weather since the mid-1990s, and thereby, mistakenly attributed corn yield increases to technology. Figures 3, 4, and 5 show key weather variables for the three states over 1960-2007. The top panel in each figure shows total June-July precipitation and the bottom panel shows average July-August temperatures. The regression model results indicated that these were the most important precipitation and temperature variables for corn production in Illinois, Indiana, and Iowa. [More]
My personal hunch is GM advances in are still largely limited to protection effects, not intrinsic yield boosts. Furthermore, drought-tolerance is a trait that doesn't payoff unless you have dry weather for msot of the current Corn Belt. Especially here in the eastern section!
None of this necessarily decreases the value delivered by GM crops to producers, and we will all make market decisions what the payback for these very expensive traits are. But I'm buying germplasm first.
Reducing any criticism of GM potential to a battle over official acceptance or not misses the point. There is no safety issue - there is a pricing issue: what is the true value of traits? And until there is more verifiable evidence, those benefits cannot be unilaterally valued by the seed company.
Besides, the real advances in GM acceptance will come from say, removing a headache from consumers. Or in this case, over-consumers.
If you're a wine lover who's prone to headaches and opposed to genetically modified crops, you have a nemesis. His name is Dr. Hennie van Vuuren, he's at the University of British Columbia's Wine Research Center, and, after sixteen years of research, he figured out how to genetically alter yeast to remove the headache-inducing properties of red wine and many white wines.
The choice between drinking conventional wine and getting walloped and drinking wine made with GM yeast and feeling vibrant poses a gastronomic conundrum for many consumers. Wine production is deeply rooted in artisanal traditions. There's nothing artisanal or traditional about GM technology. And a genuine headache, as any serious wine drinker knows, is something fierce. [More]
I research GM corn yields, so why not this GM trait as well?