I doubt that we can really answer this for both are about to do us in. The combination is a case of the whole being more than a sum of its parts.
The question is muddied with all sorts of misunderstanding. There is a mindless argument that lumps concerns about GMOs with climate denial and lack of belief in evolution. Nothing could be further from the truth. Many of the concerns about GMOs are real and based on good science.
Among the most naive arguments is that we have genetically modified organisms for centuries by breeding. This is true. And it is different than manipulating DNA in the lab.
GMOs are the latest threat Monsanto and its ilk have brought forth through science. Science has been misused often and in this oligarchy we should not be surprised. Read on below and I'll try to clarify some of this.
The active ingredient of Monsanto's Roundup is Glyphosate
Glyphosate (N-(phosphonomethyl)glycine) is a broad-spectrum systemic herbicide used to kill weeds, especially annual broadleaf weeds and grasses known to compete with commercial crops grown around the globe. It was discovered to be a herbicide by Monsanto chemist John E. Franz in 1970. Monsanto brought it to market in the 1970s under the trade name Roundup, and Monsanto's last commercially relevant United States patent expired in 2000.
Glyphosate was quickly adopted by farmers, even more so when Monsanto introduced glyphosate-resistant crops, enabling farmers to kill weeds without killing their crops. In 2007, glyphosate was the most used herbicide in the United States agricultural sector, with 180 to 185 million pounds (82,000 to 84,000 tonnes) applied, and the second-most used in home and garden market where users applied 5 to 8 million pounds (2,300 to 3,600 tonnes); in addition, industry, commerce, and government applied 13 to 15 million pounds (5,900 to 6,800 tonnes). With its heavy use in agriculture, weed resistance to glyphosate is a growing problem. While glyphosate and formulations such as Roundup have been approved by regulatory bodies worldwide and are widely used, concerns about their effects on humans and the environment persist.
Glyphosate's mode of action is to inhibit an enzyme involved in the synthesis of the aromatic amino acids: tyrosine, tryptophan, and phenylalanine. It is absorbed through foliage and translocated to growing points. Because of this mode of action, it is only effective on actively growing plants; it is not effective as a pre-emergence herbicide.
Some crops have been genetically engineered to be resistant to glyphosate (i.e., Roundup Ready, also created by Monsanto Company). Such crops allow farmers to use glyphosate as a postemergence herbicide against both broadleaf and cereal weeds, but the development of similar resistance in some weed species is emerging as a costly problem. Roundup Ready soybean was the first Roundup Ready crop.
So where is the problem? The answer is one we will not get easily. The polarization is very pronounced and claims are everywhere. Two things we need to be aware of: It's use is very widespread
Glyphosate is effective in killing a wide variety of plants, including grasses and broadleaf and woody plants. It has a relatively small effect on some clover species. By volume, it is one of the most widely used herbicides. It is commonly used for agriculture, horticulture, viticulture, and silviculture purposes, as well as garden maintenance (including home use).
In many cities, glyphosate is sprayed along the sidewalks and streets, as well as crevices in between pavement where weeds often grow. However, up to 24% of glyphosate applied to hard surfaces can be run off by water. Glyphosate contamination of surface water is highly attributed to urban use. Glyphosate is used to clear railroad tracks and get rid of unwanted aquatic vegetation.
In addition to its use an herbicide, glyphosate is also used for crop desiccation (siccation) to increase the harvest yield and, as a result of desiccation, to increase sucrose concentration in sugarcane before harvest.
The toxic effects of glyphosate are many and yet seemingly not severe according to "official" studies. Yet we have Monsanto's attempts to use studies that are questionable at best:
On two occasions, the United States EPA has caught scientists deliberately falsifying test results at research laboratories hired by Monsanto to study glyphosate. The first incident involved Industrial Biotest Laboratories (IBT). The United States Justice Department closed the laboratory in 1978, and its leadership was found guilty in 1983 of charges of falsifying statements, falsifying scientific data submitted to the government, and mail fraud.In 1991, Don Craven, the owner of Craven Laboratories and three employees were indicted on 20 felony counts. Craven, along with fourteen employees were found guilty of similar crimes.
Monsanto has stated the Craven Labs investigation was started by the EPA after a pesticide industry task force discovered irregularities, that the studies have been repeated, and that Roundup's EPA certification does not now use any studies from Craven Labs or IBT.
Like much of the other controversy we are exposed to this one masks the real problem. I will restate what I said at the beginning: Monsanto and global warming are both doing us in. The reason is obvious when you step out of the box you have carefully been put in and think about what is going on from a system's perspective. The argument about glyphosate misses the point entirely!
You can reduce the reality of your world to separate issues and engage in battle after battle and take on issue after issue. You may even win a few fights. Meanwhile the system is grinding on.
Monsanto and fossil fuels are part of a much bigger problem. It is the system we have accepted as our "real world".
I'll indulge in a reduction and consider Monsanto as a part of a system that is doing us in. There always has been at least one alternative and Monsanto knows this or they would not be so active in crushing it. To exemplify this alternative consider the work and writings of Wendell Berry. In this now famous work the title tells the story: The Unsettling of America: Culture & Agriculture In 2008 I had the privelege of keynoting a conference where Berry spoke. His concept is sound and it points to the way the system has reduced Agriculture to another "business" rather than a way of life and a way of sustaining life.
Since its publication by Sierra Club Books in 1977, The Unsettling of America has been recognized as a classic of American letters. In it, Wendell Berry argues that good farming is a cultural development and spiritual discipline. Today’s agribusiness, however, takes farming out of its cultural context and away from families. As a result, we as a nation are more estranged from the land—from the intimate knowledge, love, and care of it.
Sadly, as Berry notes in his Afterword to this third edition, his arguments and observations are more relevant than ever. We continue to suffer loss of community, the devaluation of human work, and the destruction of nature under an economic system dedicated to the mechanistic pursuit of products and profits. Although “this book has not had the happy fate of being proved wrong,” Berry writes, there are good people working “to make something comely and enduring of our life on this earth.” Wendell Berry is one of those people, writing and working, as ever, with passion, eloquence, and conviction.
As I said this too is a reduction but far less a reduction than the way issues are presented to us. It is part of a world view that we as a species have developed and that world view has estranged us not just from the land and the food that sustains us but also from nature as a whole and the planet we inhabit.
Seeing through the eyes of someone like Berry or me you can't go back. Yes you can play the game the old way, but without conviction. Reality is too strong to allow a relapse. If you are not already there I challenge you to make the leap. Imagine a world without Monsanto. Better yet, imagine a world where we acknowledge the fragility of our existence on this planet and our dependence on a decent relationship with nature. You will see with new eyes and experience new pain as you look around. It will be worth it though for you will also have a realistic way to hope.