How can healthy soil and plants improve food security?

Since arriving at Clark in 2021, Biology Professor Chandra Jack has been patiently waiting for a greenhouse where she and her students could study how microbe interactions affect plant traits — research that could help lead to the development of new, more sustainable ways to boost food production and curb famine in a world beset by climate change.

With the opening of Clark’s 1,275-square-foot Experimental Plant Investigation Center (EPIC), she’s now “exceedingly happy” to have her own lab there, right next to another one for Biology Professor Kaitlyn Mathis, who studies ants’ interactions with plants and other insects. Both are affiliated with Clark’s School of Climate, Environment, and Society, set to open in Fall 2025.

The greenhouse’s up-to-date climate controls are vital to the professors’ research. In one project funded by a $450,000 National Science Foundation (NSF) grant, Jack seeks to determine the conditions under which Trifolium barbigerum (bearded clover) attract beneficial microbe “partners,” the rhizobia bacteria that establish themselves below ground, at the plant’s root nodules. Through a complex biochemical process, the rhizobia fix nitrogen, which is crucial to plant growth and soil fertility.

Plants, microbes, and a changing climate

Jack’s research into plant-microbial relationships could be critical to our understanding of how the organisms might adapt to climate change and whether agricultural crops could be affected, positively or negatively. Her studies could help determine the possible impacts on food security.

A study by Jack and her collaborators provides more insight into how plants and microbes have evolved to develop mutually beneficial traits, potentially indicating how the organisms might adapt to climate change. Their findings were published in a 2021 article in Proceedings of the Royal Society B: Biological Sciences.

“Joint traits with a multi-genomic basis can affect the fitness of multiple species, changing how we think about evolution,” they write. “Understanding the evolution of multi-genomic traits thus enhances our ability to predict how mutualisms will adapt in a changing world.”

“There are so many things that we don’t know about plants and how useful they can be to improving the earth.”

— BIOLOGY PROFESSOR CHANDRA JACK

Such studies require scientists to carefully control their experiments in the lab to replicate as closely as possible what is happening in the field. Jack sets and monitors her greenhouse lab’s temperatures (73 during the day and 68 at night), humidity levels, and LED lighting and irrigates her plants with filtered water, which contains few minerals that could alter her research. If she’s off campus or even upstairs in the Cathy ’83 and Marc ’81 Lasry Center for Bioscience, she can doublecheck and remotely control the settings for the first-floor research space.

“The quality of the lab and the opportunity to do research year-round even exceeds that of some research-intensive universities with older greenhouses that don’t necessarily hold temperature or maintain stable conditions, especially in the summer,” says Jack, whose research also is funded by a $420,000 grant from the U.S. Department of Agriculture.

“The opportunity to have something that is environmentally controlled is so important. It provides me with different opportunities for research,” at all times of the year, she adds.

Student research in Jack’s lab

Ph.D. students Samia Riaz and Fatemeh Noori and undergraduate biology major Wiktoria Golemo ’26 are currently working with Jack on the NSF project. They also are conducting their own research projects in the greenhouse lab.

Riaz is examining how the bacteria “signal” the Trifolium plant to be “chosen” as the rhizobia partner, while Noori is studying how the bacteria strains’ genomics affect the plant’s growth and survival.

This spring, Golemo will begin her Albert, Norma and Howard Geller ’77 Endowed Research Award-funded research project, “Identifying Evolved Microbial Adaptive Climate Change Responses in Native and Invasive Medicago Polymorpha,” or burr clover, which Jack grows and studies in the lab.

The research could increase “understanding of the interconnected effects of geographic location and salinity concentrations in the microbiome, and rhizobial inoculation could assist farmers in adapting to environments exacerbated by climate change,” according to Golemo.

Studying wheat, corn, and other cereal crops

In the EPIC lab, Jack also is growing Ryan soft white spring wheat, a variety developed in 2016 by Washington State University, where she held a post-doctoral position. The hearty wheat has great potential as a cereal crop, according to WSU, with “early maturity, very good adult resistance to stripe rust, shorter height with very good straw strength, good test weight, Hessian fly resistance, aluminum tolerance, and excellent yield potential in low, intermediate, high rainfall, and irrigated production areas.”

The evolutionary biologist and her Washington State collaborators are investigating the differences in microbial biodiversity found in wheat planted in long-tended agricultural sites versus natural prairie areas.

“We want to know if the microbes that we find function differently,” Jack explains. “Prairies haven’t been disturbed much, whereas agricultural areas have faced constant displacement, fertilizers, and pesticides. We’re thinking about what makes a healthy soil and what are the implications for food production.”

In a recent article published in the open-access Canadian Journal of Microbiology, Jack and her co-authors write that their research “indicates that agricultural intensification has affected soils in a way that changes early seedling establishment and the timing of heading for wheat, but these effects may not be caused by microbes, and instead may be caused by soil nutrient conditions.”

Jack would like to expand her food-crop research to corn, planting it in the greenhouse so she can explore how to improve its growth. She also will introduce special “nitrogen fixers” to plants, investigating how such microbial inoculants “might impact crop production in wheat, corn, and other cereal crops.”

“The appeal of using microbial inoculants to mediate plant traits and productivity in managed ecosystems has increased over the past decade, because microbes represent an alternative to fertilizers, pesticides, and direct genetic modification of plants,” she explains in a 2021 Trends in Microbiology article, in which she and her co-authors “outline potential negative consequences of microbial invasions and describe a set of practices … to prevent microbial inoculants from becoming invasive.”

In another collaboration, Jack is working with faculty researchers at WPI who are investigating how plants and bacteria work together to leach and remove heavy metals from contaminated soil. She will help teach the researchers’ students how to germinate seeds and observe the developmental stages of plants.

“There are so many things that we don’t know about plants and how useful they can be to improving the earth that has been harmed by humans,” she says.

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Hands-on research in the Jack lab

In Professor Chandra Jack’s lab, student researchers conduct how microbe interactions affect plant traits — research that could help lead to the development of new, more sustainable ways to boost food production and curb famine in a world beset by climate change.

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All photos by Steven King, University Photographer

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Explore climate and sustainability issues as a student at Clark