The North American Arabidopsis Steering Committee named Mary Lou Guerinot a 2026 recipient of its Philip N. Benfey Arabidopsis Community Lifetime Achievement Award, recognizing more than four decades of research on how plants absorb and use metals from soil.
The award honors scientists who’ve spent multi-decade careers advancing research on Arabidopsis thaliana, the small weed that has become the standard laboratory model for plant biology, while also mentoring the next generation of researchers and serving the broader scientific community.
Guerinot, the Ronald and Deborah Harris Professor in the Sciences in the Department of Biological Sciences, shares this year’s honor with Dame Caroline Dean of the John Innes Centre in the UK and Julian Schroeder of the University of California, San Diego.
Guerinot’s citation for the award credits her as a “world leader” in plant nutrition research and a pillar of the Arabidopsis community. It traces her leadership to the early 1980s, when she began applying genetics to a field still dominated by traditional plant physiologists who weren’t especially receptive to the approach.
That early work led her to IRT1, the iron-regulated transporter that plants use to pull iron out of soil. IRT1 turned out to be the founding member of a transporter family with counterparts across the animal and fungal kingdoms as well. Guerinot later used protein engineering to sharpen IRT1’s selectivity for iron by eliminating its ability to also carry zinc.
Iron and zinc deficiency affects an estimated 2 billion people worldwide. Since plants are the source of most of those metals in the human diet, her research on how plants take up, move, and store them feeds directly into efforts to fight malnutrition. Guerinot was among the first plant biologists to use synchrotron X-ray fluorescence microprobe imaging, a technique for tracking trace elements inside plant tissue. In 2006, she used it to see the spatial distribution of iron inside an Arabidopsis seed, work published in Science.
Guerinot went on to help develop the field of ionomics, which draws on genomics and bioinformatics to map the connections between a plant’s genes and its mineral makeup. The open-source ionomic database built from that work is still used by researchers to identify genes tied to crop mineral content.
As part of the Dartmouth Toxic Metals Superfund Research Program, where an interdisciplinary team studied how arsenic and mercury disrupt ecosystems and the food supply, Guerinot’s group used ionomic approaches to identify genes that regulate how food crops take up those metals. Field trials in Bangladesh, China, Arkansas, and Texas turned up rice varieties with altered arsenic levels.
Guerinot has published more than 150 papers, and her many honors include the Stephen Hales Prize and the Dennis R. Hoagland Award from the American Society of Plant Biologists, as well as Dartmouth’s Graduate Mentoring Award and Dean of Faculty Award for Outstanding Mentoring and Advising.
Guerinot is a fellow and past president of ASPB and a fellow of the American Association for the Advancement of Science. In 2022, she was named a nonresident fellow of the Salk Institute in La Jolla, California, and in 2016 she was elected to the National Academy of Sciences, where she served on the academy’s governance council.
In April 2026, Guerinot was elected a fellow of the American Academy of Arts and Sciences. She’ll be inducted at a ceremony in Cambridge, Mass., this October.
She also served on the National Science Foundation’s Advisory Committee for Biological Sciences and the board of directors for the Genetics Society of America, and served on the scientific advisory board and board of directors for the Boyce Thompson Institute.
“A game-changing advisor and mentor”
Guerinot has mentored roughly 120 undergraduates, 43 of whom completed honors theses under her guidance, along with nearly 50 graduate students and postdocs. She served as one of the primary mentors for Dartmouth’s Women in Science Program for more than 20 years and was the first woman to chair a science department at Dartmouth.
Guerinot’s award citation includes several testimonials from former students and postdocs. One mentee wrote: “It’s important to highlight something extraordinary about Mary Lou’s record as an advisor and mentor—she has given her trainees the ability and freedom to deviate from her path; to create themselves in their own vision, rather than become clones of her or her career. This doesn’t happen by chance—it comes from a commitment to seeing value in divergent paths while trusting and walking alongside one’s mentees. I hope all students encounter a game-changing advisor and mentor like Mary Lou, and that all these people receive the recognition and gratitude they deserve. Their impacts on individuals and the world are beyond measure.”
Another described Guerinot as striking a rare balance: asking the ambitious questions that defined the field of iron and zinc nutrition in plants and holding her lab to high standards, yet staying open and generous with her time, resources, and offering credit toward her lab members and collaborators.
Guerinot says the recognition belongs as much to her lab as to her. “Receiving this award means a great deal to me. The accomplishments of my lab over the years have been a true team effort,” she says. “As a mentor, I have always strived to support and guide my trainees, and I was deeply touched to read their reflections on the impact I’ve had. It is a privilege to work alongside such talented, dedicated colleagues and to celebrate our shared successes.”
This year’s three honorees will take part in a NAASC panel webinar this fall, where they’ll discuss their careers with the wider Arabidopsis research community.