We may need 70% more crop production by 2050 to keep up with food demand, and that's scary for several reasons. One, yield gains are flattening out among farmers in developed countries, despite high use of pesticides and artificial fertilizers. And, two, in places where yields are low—like on small farms in Africa—farmers are likely to turn to pesticides and artificial fertilizers, deepening environmental problems.
But some scientists believe we're on the cusp of developing viable alternatives to pesticides and heavy use of artificial fertilizers. They're investigating the plant microbiome: the billions of bacteria living in roots, leaves and soil that help plants absorb minerals and nutrients, fight disease, and resist drought and heat. The equivalent of the human microbiome—the bacteria and fungi in the gut that help us digest food and fend off infection—the plant microbiome could hold the key to generating more food without the side-effects associated with high-input farming, including damage to waterways and toxicity in food.
"The microbiome has a lot of potential for agriculture because we know that microbes have a lot of influence on plants, how well they grow, how they resist pests and diseases, and how well seeds germinate," says Kelly Smith, director of microbial development at AgBiome, a startup in Durham, North Carolina.
"If we can understand how to harness microbes to do specific things, we'll have the ability to carry out a lot of the same functions that we currently depend on chemical pesticides and fungicides to do," Smith says. "Modern pesticides are a lot safer than the old ones, but the microbes have the potential to be safer still."
AgBiome is about to launch its first product, a broad-spectrum insecticide called Howler. Isolated from cotton roots in Texas, the microbes come in powder or spray form and are then grown in a laboratory (no genetic manipulation needed). They stay fresh enough for 18 months, the company says, and can survive at up to 90 degrees Fahrenheit.
Microbial solutions are not only less toxic, but also potentially more efficient for farmers. After spraying with pesticides, growers must wait several hours or even days before re-entering fields and greenhouses to tend or pick crops (up to seven days in the case of raspberries). With microbes, the re-entry period is non-existent.
AgBiome is also identifying microbes that can control weevils that attack sweet potato plants in Subsaharan Africa. The research is funded by the Bill & Melinda Gates Foundation, which wants to protect a vital source of vitamin A, a nutrient that prevents blindness and improves immune systems. Smith says AgBiome will look for microbes locally as well as scour its existing library of 26,000 microbial strains. "The weevil insect does a lot of damage to smallholder farmers who depend on sweet potatoes as a staple food crop, and there are no good products they can use now," she says.
Biological pesticides, like those derived from essential oils, have been available for several years. But, until recently, they've had a reputation for being either expensive, inadequate, or both. AgBiome claims Howler is 20 times more effective than other biological products and can completely replace traditional fungicides, not just limit their use. "There's usually a dichotomy between efficacy and economics and we're attempting to change all that," Smith says.
Have something to say about this article? You can email us and let us know. If it's interesting and thoughtful, we may publish your response.