November 15, 2018 | By Sarah Hovinga

Guest Commentary - Kombucha for Crops: How Fermenting Natural Microbes Can Keep Pests Away

By Sarah Hovinga, project and product support lead, Bayer
Fermented food and drinks, from kimchi to kefir and kombucha, have seen their popularity soar, thanks to their probiotic qualities. And it’s not just food that can be fermented. The same centuries-old chemistry is also now inspiring a 500 percent growth in the market for biological crop protection products, including those produced through the fermentation of bacteria.
Scientists have found naturally-occurring microbes that have pesticide-like qualities in diverse locations around the world—from the rainforests of Indonesia to a peach orchard in California. When fermented, these microbes can be multiplied and used by both conventional and organic farmers to help keep their crops healthy and thriving, with bigger yields and fewer losses to disease and insects.
Fermented products based on these tiny micro-organisms, which exist in particularly high numbers in soil, have several benefits. First, they can protect against certain pests such as caterpillars, which attack crops and can spread rapidly, causing huge damage to farms. A bacteria called Bacillus thuringiensis (Bt), for example, produces crystals when fermented that can kill off pests before they can damage crops. This is one possible solution for tackling the on-going plague of Fall Armyworm, a caterpillar that has devastated maize yields in Sub-Saharan Africa and has now spread to India.
Secondly, biological products—together with synthetic products—can protect against disease, offering another useful tool in the farmers’ toolbox to protect crops. Fermented Bacillus subtilis can ward off Botrytis, a fungus that causes rot among grape vines, which is a particular problem for winemakers. It is also an example of how diseases can be managed on multiple fronts: chemical products can be fast-acting and effective when aggressive disease strikes while biological products can help if resistance to traditional pesticides has developed and if disease presence is low to moderate.
Finally, fermented microbes can also be used to promote healthy growth, not only protecting crop yields but improving them as well. The bacteria Rhizobium has been found to promote growth in soybean, producing nodules on the plants’ roots that help it better absorb nitrogen, an essential nutrient. It is this versatility and potential to protect and sustain crops that is expected to attract investment of around $270 million into research and development by 2019. And it is a market that is ripe for constant innovation and creativity, which is why it has spawned so many start-ups.
But fermenting bacteria to protect crops is a highly specialized sector. In the same way that making kombucha at home can go awry, farmers can also be let down by unapproved or unregulated producers of biological crop protection products that do not adhere to high standards for product quality and efficacy.
It is down to the crop protection industry to advocate for and maintain high standards for our products. Yet with 40 percent of crops lost to fungal disease and infestation every year, biological crop protection products, along with traditional pesticides, are increasingly vital to food security. And fortunately, biological crop protection is one trend that is here to stay.


The Global Food and Agriculture Program aims to inform the development of US policy on global agricultural development and food security by raising awareness and providing resources, information, and policy analysis to the US Administration, Congress, and interested experts and organizations.

The Global Food and Agriculture Program is housed within the Chicago Council on Global Affairs, an independent, nonpartisan organization that provides insight – and influences the public discourse – on critical global issues. The Council on Global Affairs convenes leading global voices and conducts independent research to bring clarity and offer solutions to challenges and opportunities across the globe. The Council is committed to engaging the public and raising global awareness of issues that transcend borders and transform how people, business, and governments engage the world.

Support for the Global Food and Agriculture Program is generously provided by the Bill & Melinda Gates Foundation.


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| By Janet Fierro

Guest Commentary - Rural Niger Women find Opportunity and Hope through Innovative Business Model

When researchers set out to find natural ways to manage a crop-destroying pest in sub-Saharan Africa cowpea fields they knew the results could have significant positive impact on smallholder farmers. What they may not have expected was the significance of the cottage industry it inspired and the entrepreneurial spirit of the rural women of Niger who led it.