Proponents of industrial agriculture tend to claim that it is the only method that’s going to feed nine billion people. In reality, industrial agriculture has triggered a biodiversity crisis in our most popular crops that threatens to wipe out agriculture altogether.

In the process of increasing yields, introducing disease-resistant genes and creating optimal crops for industrial harvest, strains of the same crop indigenous to cultures that practice traditional agriculture are typically lost.

The 20th century has been characterized by a dramatic loss in biodiversity in the plants we cultivate. To give some numbers, 90% of the wheat varieties used in China in the last century are now extinct, while 93% of all seed varieties sold in the United States in 1903 were extinct by 1983. The introduction of genetically modified crops has merely made the global biodiversity crisis even worse.

Why is biodiversity so important? The problem we face is that pathogens like stem rust adapt to plants. If all of our domesticated plants are genetically rather similar, it’s easy for a pathogen to spread from one plant to another, decimating our entire food supply.

This is what happened to our bananas. Before we began to grow the currently popular banana race, we used to grow a banana known as the Gros Michel. Low genetic diversity allowed a fungus to practically wipe out this strain and the industry moved on to an inferior tasting substitute.

Until the 20th century, the world consists of small communities where people preserved their own strains of plants for generations. Biodiversity, along with relatively infrequent travel made it difficult for a pathogen to spread throughout our entire global food supply.

The few crops we grow today are typically themselves the benefactors of the massive biodiversity that once existed, yet threaten to annihilate it. In wheat, stemrust resistance gene 21 was inherited from einkorn wheat, a primitive form of domesticated wheat, that looks very much like its primitive ancestor and inherits a number of its disadvantages (low yield) that led it to lose ground in the 20th century.

Stemrust resistance gene 31 in wheat was inherited from rye, wheat’s rebellious cousin. Rye commonly used to grow voluntarily in fields of wheat, resulting in the mixture of wheat and rye that medieval Europeans typically used to produce bread, until humans transitioned to industrial agriculture.

If our food’s biodiversity has disappeared, how come we don’t see massive epidemics of fungal infections that decimate our crops? The answer here is that industrial agriculture manages to keep most of these outbreaks under control, by using a continually growing arsenal of chemical pesticides.

By keeping our farmland a sterile place devoid of life, where crops are grown in the absence of any species that might harm them, we can continue to grow crops that are maximized for yield and ease of mechanical harvest at the cost of genetic diversity.

There are certain disadvantages of course, including the fact that plants grown in a sterile environment tend not to produce the various compounds like salicylic acid that protect them against pathogens and have been shown to improve human health, but as long as the consumer is not aware of this unfortunate side-effect, he will happily continue to chow on his sterile food devoid of nutrients.

It is now estimated that the average Dutch potato is sprayed with a total of 36 different pesticides. The farmers often have little choice and are well aware of the burden it places on their own health, they do what’s necessary for their company to remain economically viable.

Although it might be possible for you and me to grow potatoes and other crops on our small plots of land (and we certainly should), the industrial scale of modern agriculture, necessitating massive plots of land covered with the same crop for year upon year necessitates spraying pesticides to avoid providing a home to any of the pathogens that would like to turn a farmer’s crops into its home.

And these pathogens learn quickly. In 1978 there were 49 known pathogens that infected chickpeas, by 1995 we were looking at 172. It should thus come as no surprise that the amount of pesticide sprayed on our crops continually grows as well.

There’s reason to believe that our growing reliance on pesticides may play a role in a growing number of health problems. Glyphosate is a prominent pesticide used on our crops. It was thought to be safe, but concerns are growing about its impact on health. Glyphosate is thought to negatively alter the balance of gut bacteria in our intestinal tract, benefiting pathogenic species as the cost of benevolent species.

Those who first began to raise the alarm bells were typically people in the farming community, who noticed that their animals were having difficulty getting pregnant and giving birth to deformed babies, until they switched over to glyphosate free food. It’s thought that the use of Glyphosate may play a role in the growing epidemic of wheat sensitivity.

What solution is there to this problem? Just as with most big problems, there exists no simple solution. It’s possible to reduce pesticide intake by eating more fruit and vegetables from your own environment. I often eat wild berries and grow various kinds of berries in my own garden.

Of course this is not an option with staple foods for most people. Fortunately, there is a different solution possible here, in the form of fermentation. Bacteria and fungi gradually break down the glyphosate found in our bread. After one hour of yeast fermentation, 21% of glyphosate is degraded. Sourdough fermentation involves allowing strains of wild yeast and lactic acid bacteria to ferment dough for multiple days.

Within agriculture, it’s important to understand that plants benefit from symbiotic relationships with fungi. Plants form symbiotic connections with ectomycorhizal fungi, which involve the release of substances by the fungi that prohibit pathogenic fungi from infecting the plants, thereby reducing the dependence on pesticides.

Plants of course can only form such symbiotic relationships with fungi if given ample time to grow, in health undisturbed soils. In contrast, many of the fruits and vegetables we eat come from greenhouses, where plants are never even exposed to soil but simply grow with their roots directly in the water.

Most pesticides we use depend on petroleum. Those who will have to grow crops in the post-pesticide era after we run out of petroleum will have to cope with an epidemic of plant pathogens that are perfectly adapted to the limited genetic spectrum of our crops. It would be wise for people to hold onto rare varieties of wheat and other crops as these plants should stand a better chance of surviving without the use of pesticides. A switch away from wheat to more niche and hardy crops like rye is also recommendable.