COSAM News Articles 2022 March Auburn researchers receive $635,169 USDA award to understand mechanisms associated with decreased mineral nutritional quality in soybeans grown in elevated carbon dioxide

Auburn researchers receive $635,169 USDA award to understand mechanisms associated with decreased mineral nutritional quality in soybeans grown in elevated carbon dioxide

Published: 03/22/2022

By: Maria Gebhardt

Soybeans grown with exposure to higher levels of CO₂ have higher yields but reduced amount of mineral nutrients, which then leads to less nutritious food affecting the entire food ecosystem.

Seven possible hypotheses about how elevated CO₂ affect plant mineral nutrition exist but never have been tested at the same time empirically. Researchers at Auburn University are collaborating to test and validate all of these theories to understand why the mineral content decreases when the amount of CO₂ increases.

“We are conducting novel research to model the nutrient transport mechanism system in soybean plants,” said Courtney Leisner, Assistant Professor in the Department of Biological Sciences. “This research will help us generate models to explain the direct impact of CO₂ on nutrient metabolism of publicly available cultivars of soybean.”

Funded through the United States Department of Agriculture (USDA) National Institute of Food and Agriculture, Leisner is working with Alvaro Sanz-Saez, an Assistant Professor in the College of Agriculture, with the $635,169 award titled Dissecting the Physiological Mechanisms of Plant Nutrient Responses to Rising Atmospheric Carbon Dioxide Levels, through Oct. 2024.

“Many possible theories exist as to why many plants have decreased nutritional content when grown in a high CO₂ environment. One main hypothesis is that when grown at higher CO₂ levels in the atmosphere they are able to assimilate more carbon through increased photosynthetic levels diluting the minerals. They also close pores on their leaves to reduce water loss, leading to a decrease in nutrient uptake due to a reduction in mass flow of water and nutrients that negatively affect the mineral quality of the plant,” Sanz-Saez said.

They will collaborate with Ivan Baxter who will perform high throughput mineral nutrient analysis (“ionomics”) and aid in modeling impacts of elevated CO₂ on nutrient metabolism in soybean. He is currently located at the Donald Danforth Plant Science Center.

“In addition to plants in growth chambers here at Auburn at the Plant Science Research Center, plants will be grown at the Soybean Free Air Concentration Enrichment (SoyFACE) facility at the University of Illinois. SoyFACE is a unique facility that allows plants to be grown in open-air conditions most similar to a normal field on commercial farms, but with elevated CO₂ conditions,” Leisner added.

“We will propose future research to modify empirically tested theories with the end goal to fortify future crops to make them more nutritious and resilient to future climate change,” Sanz-Saez said.

Leisner and Sanz-Saez are seeking answers to why the plant biomass increases but mineral content decreases as the level of atmospheric CO₂ rises. As increases in anthropogenic CO₂ emissions continue to cause global climate change, their research will provide insight to help farmers grow more nutritious and efficient crops making an impact around the globe.