A big idea for agriculture

student working in a lab

Most of us have seen the ads for yogurt that improves our digestive system biome. A Doane University team is part of a statewide group of scientists studying how plants, through their roots, interact with their environments – the soil biome.

The big idea for agriculture, said Tessa Durham Brooks, is to improve interactions between plant roots and the soil’s microbes (biome). It is, she said, a “holy grail of agriculture.” Healthy soil in theory improves plant health and vigor, boosts yields, and requires fewer inputs like fertilizer. Corn, for instance, takes a lot of nutrients from soil, but does applied fertilizer improve the soil, or put it on life support, Durham Brooks asked. “We know there are environmental impacts and production expenses from fertilizers and it would be good to find ways to reduce the need for it,” she said.

But first, scientists need to know how roots interact with soil.

Durham Brooks, associate professor of biology, and colleague Erin Doyle, assistant professor of biology, are working on a $931,258 sub-award from the National Science Foundation through Nebraska EPSCoR, a large statewide research project involving scientists from Doane and the University of Nebraska-Lincoln, University of Nebraska Medical Center and University of Nebraska at Kearney. The $20 million Center for Root and Rhizobiome Innovation project launched in 2016 and runs till 2021.

Durham Brooks, Doyle and Doane chemistry professor Andrea Holmes are working with undergraduates to study how roots exude chemicals, and how those chemicals affect the soil microbes. The interdisciplinary faculty team has expertise in plant physiology, computational biology and organic chemistry.

“We are part of an effort to build a detailed model and in theory we can perturb (introduce a change) and predict outcomes,” Durham Brooks said. “We can see which chemicals attract microbes and if we add more or less, what happens. This adds to the body of data and is our part of the $20 million puzzle.”

Early simple tools involved printing ninhydrin, a chemical that detects the presence of amino acids, on tissue paper, then using the paper to “blot” seedlings growing on the absorbent paper. As roots developed, scientists could see where roots were exuding the amino acids, creating a “chemical fingerprint” that shows where compounds are located, although it doesn’t identify the specific amino acids (a research team at another institution is pursuing that question). Now, they are using a more advanced process that allows them to see how much amino acid is being exuded.

Doane scientists’ jobs were to create the technique from which other studies will follow. In addition to the faculty team, several undergraduates and a technician are involved on the project as well.