Genetically modified crops may have unseen benefits
I got into a bit of a Facebook tiff a few months ago, on the topic of GMO crops and their effects on human society. I took perhaps an extreme stance on the topic, as I maintained that humans have been genetically modifying organisms for all of recorded history, so the sudden concern is perhaps a bit misplaced. Consider for example how corn appears today, in comparison with the wild variety from several hundred years ago in the graphic to the right. Indeed, we have so significantly modified many organisms so much that they may be unable to survive without human help.
Opposition to GMO crops mainly stems from two lines; first, that there may be unforeseen dangers due to their modification with regards to human health, and two, modern monoculture may have some undesirable cultural and business-related outcomes. These are two completely different objections, and so should be dealt with as separate discussions.
I came across an interesting news summary on Science Daily recently, entitled “Benefits of Bt corn go beyond rootworm resistance.” Corn has been modified to express a toxin produced by the bacterium Bacillus thuringiensis. This bacterium is a natural pathogen of the caterpillar form of several insects, and in fact powder containing B. thuringiensis has been used as an insecticide since the 1960’s. In the 1990’s, the gene for Bt toxin (the toxin the bacterium makes that actually kills the caterpillars) was inserted into the corn genome, allowing the corn plant to make the toxin itself, without the need for the bacterium.
The Science Daily summary tells the story of researchers at the University of Illinois set out to see if Bt-containing corn plants grew any differently than control plants. These results have been published in the journal Crop Science. What they found was that the root systems of Bt containing corn plants were significantly more robust than the control plants. The higher yields from the GMO plants have been recognized as their most significant benefit since they were introduced, however the improvement in the root structure leads to an additional benefit; less fertilizer needs to be given to the plant, as they are able to utilize nitrogen more efficiently. Excess nitrogen fertilizer use can have toxic effects itself on the soil, and agricultural runoff into tributaries can lead to algal blooms and fish die offs. Routes to minimize the use of nitrogen fertilizers would have very positive impacts on the environment. The researchers hope that by better understanding the formation of root systems and the very positive effects that Bt-expression has on this process, that farmers can more effectively target fertilizer applications and minimize effects on the environment.