How Sugar’s Bacteria Could Point the Way to More Efficient Agriculture

New research proves the power of beneficial bacteria and fungi that help sugarcane grow larger and rebound from stress faster

corn plants inoculated with sugarcane microbes comparison
On the right, corn plants inoculated with sugarcane microbes saw their biomass increase compared to those that were not inoculated (on the left). Rafael S. C. de Souza

Geneticist Paulo Arruda was mapping the microbiome of sugarcane—some 20,000 bacteria and 10,000 fungi—when he realized that some of the microorganisms were much more abundant than others. Along with the other researchers at Brazil’s Genomics for Climate Change Research Center (GCCRC), he set out to answer the question that immediately jumped to everyone’s mind: If these microorganisms managed to multiply to such high numbers, were they also helping to facilitate the growth of the sugarcane? And if so, could those microbes be harnessed to increase production of other crops?

“In the agriculture sector, there’s a very big challenge, which is how to produce more—because the expectation is that the population will continue to grow—and how to do it in a way that’s sustainable, so using fewer chemical products, fewer pesticides and less water,” Arruda says. “It’s a colossal challenge. And how can we do this? By researching technologies like these, that use things like microorganisms, which are found and already exist in nature.”

Arruda and the rest of the team decided to test the efficacy of these microbes with both lab and field tests on corn, inoculating some plants with the abundant microorganisms that facilitated sugarcane growth, inoculating others with less efficient sugarcane microorganisms, and leaving others still without any inoculation at all.

The results were even better than expected. Not only did the corn inoculated with the more efficient microorganisms grow to have a biomass up to three times its usual size, but it also became more resilient to drought conditions, taking longer to feel the effects of a lack of water during dry periods and recovering more quickly after suffering hydric stress.

The fungi and bacteria were capable of making physiological changes to the plants, too, dropping the temperature of their leaves by up to 4 degrees Celsius and reducing their water consumption. In one field test run in Luís Eduardo Magalhães, a town in the northeastern state of Bahia known for its agribusiness and long periods without rain, the microorganisms even showed signs of battling an illness known to reduce the production of ears of corn.

plant in pink-tinted soil
Understanding microbiomes is considered one of the most promising technologies in 2020. GCCRC

For Arruda, the discovery of this clean technology could help farmers—particularly those with small- and medium-sized operations—produce better crops more consistently, which will then trickle down to create stronger food security in all categories.

“These plants are the basis of animal feed used during production,” Arruda says of the types of crops being studied at the GCCRC. “So when you eat beef, you’re eating something that was raised with feed that includes corn and soy. It’s the same for milk, eggs and chicken, as well as the direct consumption of those plants.”

If this type of microorganism-facilitated agriculture can scale, it could be a huge boon to producers, particularly as growers face more inconsistent climates as global temperatures rise. “It lessens the risk for the producer, which is the main benefit, and it also helps increase food security,” says Eduardo Trevisan Gonçalves, an agronomist and project manager at the nonprofit IMAFLORA (Forest and Agricultural Management and Certification Institute) who is not involved in the GCCRC project. “These clean technologies answer demands from both rural producers and consumers. This helps with food security and the food chain more broadly, as a whole. I think this is the type of technology that everybody is looking for.”

Testing hasn’t yet come to an end, but so far the sugarcane microorganisms used to inoculate the corn crops have had only positive effects. Arruda hopes that means the biotechnology he and the GCCRC team have discovered will draw the attention of seed and crop inoculant companies, allowing the method to be incorporated into their products and making it easier for all farmers to benefit from the sugarcane’s microbiome.

“That’s what we want to do: have partnerships within the industry so that this technology has a wide reach,” Arruda says. “Because there’s no point in giving this technology to a small number of rural producers. If our tests show it works more widely, it could have an important impact on helping those producers stay in business and keeping food on the table for so many people.”

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