A FOURTH AGRICULTURAL REVOLUTION IS UNDERWAY. WHAT SHOULD WE CALL IT?
To avoid diving down a rabbit hole to answer this question, I have one piece of advice: follow the seeds.
We are on the cusp of an agricultural revolution. While many agree this is the case, things quickly get contentious. Is this the Fourth Agricultural Revolution, the Fifth, or even the Seventh? Does marrying the power of digital technology with farming qualify as the next agricultural revolution? Or should the title go to genetic breakthroughs that vastly speed the breeding of crops with traits that improve yields and withstand stress?
Unfortunately, there is no one authority that determines what constitutes an agricultural revolution. A review of the literature reveals many competing candidates beyond the two leading contenders cited above. While the ambiguities are frustrating, the question is profoundly important. We need a new agricultural revolution to feed an additional two billion people in the coming decades. Agriculture gave rise to civilization itself, and no civilization can persist unless it can feed its people.
Recently, the Royal Swedish Academy of Sciences gave powerful support for the case for genetic breakthroughs as the next agricultural revolution when they awarded the Nobel Prize in Chemistry to Dr. Jennifer Doudna of The University of California Berkeley and Dr. Emmanuelle Charpentier of the Max Planck Institute for Infection Biology for their work developing CRISPR — a powerful tool for making intentional changes at the genetic level. In doing so, the Academy recognized that intervening at the genetic level in a precise manner opens vast new frontiers for solving problems that bedevil humanity.
While the use of these tools on mammals and humans involves tricky ethical considerations, there is no such controversy when it comes to agriculture. After all, breeding better seeds has been the goal of agriculture since indigenous peoples started planting tubers over 10,000 years ago.
Follow the Seeds
This points to a simple way to think about agricultural progress: focus on the seeds. From the dawn of farming to the present day, seeds have always been the most valuable component of agriculture. The first agricultural revolution marked the advent of agriculture itself — a transition from hunting and gathering to planting domesticated seeds and harvesting the resulting crops. As farmers began to plant primitive forms of wheat, rice and corn, they also began to search for more productive and robust seeds to plant.
The most common description of the second agricultural revolution involved steps towards its mechanization, which paralleled the industrial revolution in the early part of the 19th century. These involved the introduction of seed planters, John Deere’s invention of the steel plough in 1837 (which permitted the conversion of tough prairie soils to agricultural land), mechanical reapers, the cotton gin and better ways of transporting and storing crops. As such, this second revolution might be seen as optimizing practices to get the most out of seeds.
The third agricultural revolution — dated to the middle of the last century and commonly called the “Green Revolution” — dealt with both developing better seeds (sturdy wheat and rice), as well as ways to take advantage of their improved genetics through fertilizers and pest control. Some fit the advent of GMO or transgenic crops into this third revolution, as GMOs allowed plant scientists to purposefully develop traits such as herbicide resistance.
The GMO Grey Area
This is one major area of contention. Some argue that the advent of GMOs should be recognized as a distinct phase in the advance of agricultural technology. Others note that persistent public concerns about transgenic technology, and inherent limitations on what it can achieve, relegate GMOs to a role as more of a stopgap or transitional technology in the ag-tech continuum.
A deeper look at the history of transgenics supports the argument that GMOs represent a byway rather than a full-fledged technological revolution. Plant breeders always prefer to add new traits to proven seeds, if only because farmers are more comfortable with a seed whose characteristics they know. If the trait comes from cross-breeding with a variant of the crop, both breeders and farmers worry about potential genetic weaknesses that may accompany the desired trait. These worries amplify dramatically if the trait comes from an unrelated species.
The obvious answer was to try to coax a new trait out of an existing plant with the least disruption possible. In the 1970s, however — when plant breeders first tried to directly manipulate the genetics of plants — biologists lacked the proper tools. They did not understand the exact location of the genes associated with a trait, nor the genetic tools to edit a specific gene. So, they did what appeared to be the next-best thing: they implanted foreign genetic material associated with given traits directly into the genome of a plant. Because the imported genetic material comes from entirely different species, these crops came to be called “transgenic.”
Enter Precision Gene Editing — and the Next “Greener” Revolution
But in the intervening years, geneticists have refined their ability to map a plant’s genome. They have also developed tools (such as CRISPR) to edit the genome at the level of a single allele — the smallest component of a gene. This eliminates worries about unwanted genetic baggage being imported, as well as concerns about unwanted side effects.
This precision gene editing technology was first developed in the late 1990s, and it has been optimized over the past 20 years. It has been shown to be successful at inculcating plants with traits such as disease resistance that transgenic technologies have not been able to achieve. More to the point, precision gene editing moots the need for transgenic or GMO approaches.
If a plant breeder can achieve a desired result while still working entirely within a plant’s genome, why import foreign genes and all their unwanted baggage — particularly since precision gene editing can breed a new trait ten times faster and at one tenth the cost of GMO? The success of precision gene editing will seal the case that GMOs represent a transitional technology and not a major technological advance.
If the seed is the standard for judging agricultural revolutions, precision gene editing is also the most appropriate champion to carry the banner for the next agricultural revolution. The other main contender — the marriage of digital and agricultural technologies — has an important role to play in making sure that farmers get the best out of the genetics of the seeds they plant. Satellite data, drones and robotics can all improve yields, but again, without the seed there is no agriculture.
The precision gene editing revolution is just getting started, but it has arrived in the nick of time. GMO crops are still met with resistance and have not delivered the improved yields or the ability to create plants that can resist disease they once promised. There is no other technology on the horizon that can rapidly and economically breed the traits needed to adapt to climate change and increasing limitations on fertile land and fresh water.
Moreover, by finding valuable traits within the plant itself, precision gene editing returns plant breeding to where it started. Every single trait that precision gene editing can breed can also be produced through natural selection; indeed, Nature magazine described the process by which edits occur as “indistinguishable” from what might be produced in nature.
For this reason, perhaps this new revolution should be called the “Greener Revolution.”