Iowa State Researchers Explore Plant-Microbe Relationships for Drought Resiliency
March 10th, 2020
AMES, Iowa — Iowa State University researchers are working to better understand how soybeans interact with the community of microbes living around their roots, and how these relationships may enhance the crop’s resiliency in the face of drought and other stresses.
The project is funded by a three-year, $750,000 grant from the U.S. Department of Agriculture’s National Institute of Food and Agriculture through its Agricultural Food Research Initiative. The research is being led by Gwyn Beattie, interim chair of the Department of Plant Pathology and Microbiology and the Robert Earle Buchanan Distinguished Professor of Bacteriology for Research and Nomenclature.
Soybeans can obtain their nitrogen through nitrogen fixation, a process that is highly sensitive to water stress. This makes the crop especially vulnerable to drought.
“We aim to understand how soybeans’ partnerships with underground microbial communities may help the plants become more resilient,” said Beattie. “With the frequency and severity of droughts increasing worldwide, it’s very important to find plant genes, microbes and management strategies that work together to sustain agricultural productivity for our most important crops.”
The research has important implications for Iowa soybean farmers and consumers. Iowa soybean growers annually produce a crop valued at more than $5 billion, and the state perennially ranks in the top two soybean producing states nationally. New research insights will help ensure the future profitability and sustainability of this crop, a critical source of protein worldwide.
Beattie’s research team also includes Dan Nettleton, chair of the Department of Statistics and Distinguished Professor and Laurence H. Baker Chair in Biological Statistics, and Basil Nikolau, professor in the Department of Biochemistry, Biophysics and Molecular Biology and Francis M Craig Professor.
The Iowa State scientists will evaluate how microbes interact with soybeans during drought to alter the chemistry and physiology of soybean roots. They’ll study how drought influences growth and development in both the plants and the hidden communities the plants depend on — also known as the “microbiome,” the community of bacteria, fungi and other microbes associated with the plant’s roots.
Beattie predicts the research could improve soybean breeding programs and inform the development of seed coatings studded with microbial species that help plants thrive in water-stressed conditions.
“Agricultural research needs to better understand how whole systems work together in the environment,” said Beattie. “Ultimately, that’s what will have the greatest influence on production outcomes. We’re trying to establish a foundation of approaches that can help exploit the untapped potential from knowledge about complex systems, including interactions among crops and other plants, microbes, insects, soils, the environment and management.”
She compares this area of study to new knowledge coming to light about the roles of microbes in human health.
“Researchers are beginning to understand how microbes in our guts influence our health. Plants’ dependence on microbes makes even more sense since they are stationary. Plants have evolved to make the best use of microbes, which can come and go, to live and endure heat, lack of water and pests. More knowledge of just how they do this can be used to our advantage.”
For the study, laboratory-grown soybean plants will be subjected to water-rich and water-limited conditions through several growth cycles. Researchers will test mechanisms by which drought-induced changes in the plant drive changes in the root microbiomes. They also will study how microbial communities from various soybean fields with a history of drought may influence soybean resilience using techniques that employ computerized cameras to track and record developing plants and the myriad, often-subtle differences between them. Information from below-the-ground will be compared with observable differences in the above-ground plants to identify microbiome features that benefit soybeans under drought.
The current research builds on previous soybean root research led by Beattie and Asheesh (Danny) Singh, associate professor of agronomy, which was funded by the Iowa Soybean Research Center at Iowa State University.
“We are thrilled to see Dr. Beattie’s important research successfully receive competitive federal funding,” said Greg Tylka, director of the Iowa Soybean Research Center. “We are proud that the center funded her team’s early work that set the stage for the new grant.”