Below the surface of the soil, a diverse community of microbes — living organisms like bacteria, viruses, fungi, and protozoa — interact and play a significant role in breaking down organic matter and cycling nutrients. These microbial interactions can improve or, in some cases, impair the health and growth of plants.
Although they cannot be seen with the naked eye, microbes could help solve a vexing problem exacerbated by climate change: By 2050, scientists and policymakers fear, farmers may not be able to produce enough food to feed the world’s growing population.
“Even if we could feed the world right now, 20 years from now, we won’t be able to — unless we make some significant changes,” says Chandra Jack, professor of biology.
By studying how microbe interactions affect plant traits, Jack hopes to contribute to the development of new, more sustainable ways to increase food production. Her research is funded by a $453,000 grant from the National Science Foundation and a $420,000 grant from the National Institute of Food and Agriculture’s Agriculture and Food Research Initiative, part of the U.S. Department of Agriculture.
“Researchers want to use microbes to replace synthetic fertilizers,” Jack says. “But we know what they can do in the lab. We don’t know what they can do in the wild or in the field.”
Microbes can “fix” atmospheric nitrogen, turning it into a component found in chlorophyll, which plants need for photosynthesis.
Legumes have a close, symbiotic relationship with microbes, according to Jack. “The microbes will enter the plant tissue and form this mass on the roots. It’s called a nodule where the nitrogen fixation happens,” she explains.
Cereal crops such as wheat and barley do not have such a relationship with nodule-forming microbes. However, Jack is examining whether “free-living nitrogen fixers” — bacteria present in the surrounding soil — could “have a tighter association with the cereal crops so that the nitrogen can be applied to those plants without having to apply fertilizers.”
Challenge. Change. is produced by Andrew Hart and Melissa Hanson for Clark University. Listen and subscribe on Spotify or Apple Podcasts. Find other episodes wherever you listen to podcasts.