Background

As North Carolina State University advances in its quest to make the Research Triangle a global hub for plant-related innovation, it launched the Plant Soil Microbial Community Consortium (PSMCC) to explore the microorganisms that make up the soil microbiome. Established in 2015, this partnership brought together the university’s Center for Integrated Fungal Research (CIFR) with stakeholders from industries and organizations vested in improving agricultural production. The consortium remained active through 2020 and has since evolved into the Plant Soil Microbial Community Collaborative, which continues to pursue these goals.

The plant soil microbiome consists of microorganisms, including bacteria and fungi, that are present on plants, in the rhizosphere, and in the bulk soil, and has the potential to be either beneficial or deleterious to plant growth and crop yields. Researchers in the consortium studied the largely unknown world of microscopic organisms living in soil along plant roots to gain a better understanding of how these microbiomes affect plants and how they might respond to changes in climate or other environmental factors. Advancing our knowledge of the dynamic soil microbiome provides insight into how we might manage these microbial communities to improve agricultural crop systems and reduce the need for synthetic fertilizers and pesticides.

Bacteria and fungi can interact with plants in many ways. While some microorganisms are pathogenic and cause disease and poor growth, many have a neutral impact or even a beneficial effect on plants. An example of a beneficial interaction is the symbiotic relationship between mycorrhizal fungi and plant roots, which occurs for more than 80 percent of all plant species. In this symbiotic arrangement, plants supply carbon to the fungi and the fungi provide nitrogen, phosphorous, other mineral-derived nutrients, and water to the plants. There is evidence that some fungi and bacteria can help plants tolerate environmental stresses such as drought and heat, and suggestions that we might be able to use microbes to prevent or ameliorate the effect of pathogenic microbes. To effectively utilize these resources, we need to understand the structure and function of the microbial communities present in our soils, as well as develop a more complete understanding of the roles of individual organisms in producing beneficial or harmful effects within the community.

Dr. Ignazio Carbone, CIFR’s director and a plant pathology professor, stated that the goal of the consortium “is to help us leverage microbes to increase plant yield, suppress disease, to essentially complement what we are doing with current agricultural practices to develop new approaches that are sustainable and environmentally friendly.”

Developing such approaches begins with a greater understanding of microbial biodiversity and how it evolves in response to farming practices and stressors such as drought and insects.

“The soil is teeming with microbial life, yet relatively few studies have mapped that diversity,” according to Dr. Carbone. “It is estimated that there are upwards of 5 million species of fungi, but we have described less than 5 percent of them. There are fungi and other microbes in nature that have applications in agriculture, can be used as biopesticides and have yet to be discovered. And our mission is to do that, to understand how the communities of soil microbes interact and how to augment these communities to improve crop vigor and yield.”