Fighting Mother Nature with Biotechnology - The Oxford Topic of Food, Politics, and Society - page 444

the breeding process, including after commercial release, due to the presence of tox-
ins. Among the best known are celery, with excessive amounts of psoralen, and potato,
with novel glycoalkaloid content (see National Academy of Sciences 2004 for additional
information on problems from new varieties from traditional breeding methods).
In the intervening years, more and more commercial farmers began growing GE
crops on a large scale, and consumers began eating foods derived from genetic engi-
neering. By 2009, GE crops were being grown in twenty-nine countries and consumed
by billions of humans (James 2010). Not one case of harm to either humans or environ-
ments caused by GE crops or foods has yet been documented.
Notwithstanding the relative safety of GE, or, to put it colloquially, “so far, so good,”
an argument has been made that GE has not, in spite of its successful invasion of world-
wide acreage, increased food production (see, e.g., Gurian-Sherman 2009). That is, the
traits in current GE crops are fairly simple, offering improved insect resistance or weed
control, but, Gurian-Sherman argues that GE has not enhanced overall yield, a highly
complex trait, so there's no “real” food production benefit from the technology.
It is true that the current GE crops were not directly engineered for yield increases,
and it's true that yield is a highly complex combination of traits; there's no such thing
as a “yield” gene. There are GE plants in various stages of development that have been
modified to enhance yield directly, by increasing, for example, the efficiency of photo-
synthesis. However, those plants are still in testing stages and not yet commercialized.
But to say the current GE crops have not improved yield or increased food production
is misleading if not disingenuous. While the GE crops do not directly increase yield,
they indirectly increase yield by reducing the constraints to yield potential. That is, in
ordinary farm systems, crop yields are reduced, sometimes substantially, by the ravages
of disease, depredation by insects, or the competition from weeds. Current GE crops,
protected from those constraints, are better able to perform up to their natural yield
potential. This is most readily illustrated in poorer countries, as US farmers ensure
high-yield potential in conventional cropping by using sufficient pesticides to limit the
pests causing the yield reduction. In poorer countries, farmers often cannot afford suffi-
cient chemical to give this high degree of control so they end up harvesting whatever the
diseases, insects, and weeds leave behind. In the Philippines, for example, when Bt corn
was first introduced, the reported corn yields increased from about 4 tons per hectare to
12 tons per hectare (Deshpande 2009). In South Africa, the introduction of GE Bt corn
since 2000 is resulting in yield increases ranging from 5 percent to 32 percent (Brookes
and Barfoot 2011).
And in the United States, a more recent study on the impacts of genetic engineering
on sustainability of US agriculture from the National Academy of Sciences concluded
that in the United States alone, farmers, society, and the environment were all beneficia-
ries of agricultural biotechnology (National Academy of Sciences 2010).
In considering issues related to sustainability, current targets of agricultural bio-
technology include such traits as drought tolerance or water use efficiency, nutritional
enhancements (such as provitamin A enriched “Golden” rice), and removal of allergens
or other toxic substances from various foods. And, with the current specter of climate