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A Future Without Fertilizer: How Microbes Are Changing Traditional Agriculture Practices

Monday, October 21, 2019

Mackenzie Allen

Research & Publications Intern

Present-day food consumption relies on high-yielding crops, and these high-yielding crops rely on nitrogen to be able to deliver 40-60% of the world’s food supply. Typically, synthetic nitrogen is provided to crops through the use of fertilizers. In 2015, an estimated 3.54 billion people were fed by synthetic nitrogen fertilizers. This extensive use of fertilizers comes with significant costs, accounting for more than $100 billion in negative economic, environmental, and human health impacts.


Currently, chemical fertilizer is the largest industry in global agribusiness and 1% of the world’s total energy is used to produce fertilizer. This process is quite wasteful, as plants only use a portion of the nitrates in the applied fertilizers and the rest often leaches into our groundwater, rivers, and streams, causing algal blooms that can suffocate aquatic life. This also leads to a situation in which the nitrogen not used by the crop can volatilize and become a greenhouse gas 300 times more potent than carbon dioxide, which is ultimately responsible for about 5% of global warming.

Fortunately, some have begun looking at ways to harness the natural ability of soil microbes to nourish food crops without the need for excessive fertilizers. Soil microbes exist naturally in the ground and can be applied directly to a seed or sprayed onto a plant. The microbes are vital to the overall health of the soil and work to help plants absorb essential nutrients and use water more efficiently. The microbes develop as the crop grows, matching the supply of nitrogen to the need of the plant. And, unlike chemical fertilizers that are mixed into the soil, nitrogen from soil microbes is transferred directly to the plant. Rather than eventually washing into waterways or volatizing into the air, the nutrients stay with the plant as it grows, constantly being recycled by the microbes. This simultaneously improves nutrient uptake within the plant while averting virtually all nutrient loss that could lead to pollution from volatilization and leaching.

Soil microbes have always been present in our environment. But after a century of applying synthetic nitrogen fertilizer to our crops, these naturally occurring organisms became dormant—as if they were in a state of hibernation—in response to the increased application of synthetic fertilizers. One company, Pivot Bio, has sought to “reawaken” microbes' ability to convert unusable nitrogen in the air into ammonia that crops could use for their daily nitrogen intakes. This nitrogen fixing process is still a relatively new area of research, and the company is currently focused on decreasing the reliance on synthetic nitrogen fertilizer rather than removing the need for it altogether. But, looking toward the future, Pivot Bio aims to eventually replace all nitrogen fertilizer with microbes that adhere to the crop’s root system and provide them daily nitrogen feedings, and essentially make them self-sustaining. This opens up the possibilities for the future, and indicates that we may have the potential to eliminate the practice of applying fertilizer to soil. Pivot Bio estimates that when the use of its product reaches 35% of the U.S. corn market, the reduction in nitrous oxide emissions will be equivalent to removing nearly 1.5 million cars from our roads. Other companies, like Monsanto, have also begun developing their own nitrogen-fixing microbes. These companies have realized the criticality of staking their claims in this market as the importance of synthetic nitrogen replacements becomes more established. Enabling nitrogen-producing microbes as a crop nutrition tool for farmers will transform agriculture.

For the past century, fertilizer has served to power and expand modern agriculture, with synthetic nitrogen fertilizer being the most widely produced fertilizer. Now, farmers have the ability to grow their crops without the same level of dependency on this fertilizer. As the world population continues to grow, it is essential that we develop and implement modern solutions for issues related to agriculture and food production. Forward-looking companies are taking steps to reduce the harmful impacts that over a century of fertilizer-heavy farming practices have made us accustomed to, and to make it possible for us to envision a future that involves feeding the world’s population without synthetic fertilizers. This would allow farmers to both maximize crop production, while significantly decreasing the risk of polluting our waterways and damaging our soils. With such innovations, we will once again be able to feel good about the food we eat.