The largest corn harvest in U.S. history is ripening in fields across America as summer rolls along. The latest figures from the USDA predict a total harvest of 13.1 billion bushels, a huge 24 percent jump over last year's harvest. The big numbers are in part a natural result of farmers planting more acres of corn than in any year since 1944, but are also due to increased yields per acre.
A Financial Times report on the new numbers suggests that bleeding-edge varieties of genetically modified corn partially explain the yield-per-acre gains. "U.S. farmers have been using record levels of new-generation seeds from suppliers such as Monsanto which are more resistant to drought and pests, boosting yields."
More, supposedly, is to come. Last October, at a presentation at the Renewable Energy Conference, Secretary of Agriculture Mike Johanns promised that new, drought-tolerant varieties of corn were in development that would boost yields in dry areas another 40 percent "not in the next lifetime but in the next few years." At the same conference Monsanto chief technological officer Robert Fraley predicted average U.S. corn yields were set to double within a generation.
That last tidbit of information comes from "Food and fuel for all: realistic or foolish?" an article by University of Nebraska agronomists Kenneth G. Cassman and Adam J. Liska in the debut issue of a new academic journal, Biofuels, Bioproducts, and Biorefining.
How the World Works readers would be properly justified in approaching such a journal with some skepticism as to whether the content might be appropriately critical of the entire biofuel project. But I'll bet they, like me, would be pleasantly surprised. Cassman and Liska's article is an excellent summary of the food vs. fuel conundrum.
Among other things, Cassman and Liska observe that despite all that biotech researchers have achieved in recent decades, over the last 40 years yield growth for agricultural grains has only grown linearly. But to double in a single generation would require exponential growth. And despite all the much-vaunted gains in our understanding of the structure of life via advances in genomic science, there's no compelling evidence that progress can be accelerated that quickly beyond its current rate. What has already been achieved required mighty effort!
U.S. maize yield trends since the mid-1960s have been supported by a powerful train of research and technology development. New breeding methods, expansion of irrigated area, soil testing and balanced fertilization, conservation tillage, and integrated pest management were the driving forces of innovation in the first 30 years of this time series. Insect resistant "Bt" maize, which is a transgenic crop variety produced by genetic engineering (commonly called a GMO), was introduced in the mid-1990s. However, despite investment of hundreds of millions of dollars in genomics and crop genetic engineering by both the public and private sectors since then, there has been little additional impact of biotechnology since Bt maize other than incorporation of herbicide resistance through the "Roundup Ready" trait, which also was discovered before the advent of genomics...
Apart from the record, some still argue that acceleration in yield gain is underway because of the power of genomics and genetic engineering to create crop varieties with substantially greater yield potential and drought resistance. Although large seed companies like Monsanto make similar claims in their annual reports, there is no scientific evidence published in peer reviewed journals to substantiate these assertions. Hence, it is not possible for scientists at large to challenge these claims. Equally disturbing is the fact that these optimistic projections have a strong influence on setting the research priorities of the U.S. Department of Agriculture and the U.S. Department of Energy. While these agencies make substantial investment in genomics and chemical engineering to improve conversion of cellulosic biomass to ethanol, there is little research funding to accelerate the rate of gain in crop yields using an ecological systems-based approach to ensure protection of environmental quality.
Cassman and Liska do not present themselves as opposed to biofuel production. They note that even just a "10 percent petroleum replacement of today's motor fuel usage [by biofuels] would represent an important component of a broader strategy that includes development of other renewable energy sources, such as wind and solar energy, and aggressive conservation measures to improve vehicle fuel efficiency." This is a crucial point -- replacing all of modern civilization's transportation fuel needs with biofuels is a foolhardy goal. But if a significant fraction could be replaced, as part of a larger portfolio approach to addressing our energy needs, biofuels could be very useful indeed.
But only if such fuels are produced sustainably. And somehow, that goal doesn't seem to be quite as high a priority for the USDA and Monsanto as some others.
The critical challenge is not only to produce enough food to meet increased demand from population increase and expansion of biofuel production, but to do so in an environmentally sound manner. Achieving these dual objectives in a relatively short time period will require a substantial increase in research and extension with an explicit focus on increasing the rate of gain in crop yields while protecting soil and water quality and reducing greenhouse gas emissions. It is sobering to note that agronomists have never been asked to develop innovative management systems that both accelerate yield gains and protect natural resources.