Got a Sick Plant? Take it to UMD’s Plant Hospital
Inside the Plant Diagnostics Lab, botanical medical mysteries meet scientific detective work.
When plants get sick in Maryland, they don’t walk into an emergency room, but they often end up in the University of Maryland’s Plant Diagnostic Laboratory—mailed in by nursery owners, dropped off by crop consultants or hand-delivered by growers who've driven hours hoping for answers.
Once inside the lab, Entomology Assistant Research Professor Ana Cristina Fulladolsa and a team of undergraduate students gather around the sick plants on a lab table, leaning in to observe a cluster of yellowing leaves or a suspicious patch of spots that might provide important clues. The team studies lesions, discusses symptoms, forms hypotheses and then confirms their theories using microscopes, DNA sequencing and other specialized equipment. When the mystery is solved, they make a diagnosis.
“It’s just like a clinic,” explained Fulladolsa, who took over the lab in 2025 after its previous director retired in 2024. “In a regular hospital, they’d ask you things like ‘what do you feel? What are your symptoms?’ and examine you to find out what’s wrong. That’s exactly what we do—but plants can’t talk, so we have to gather as much information as we can through other means.”
For Fulladolsa, that means combing through grower-submitted forms, studying photographs taken in the field and running a vast array of diagnostic tests, from simple visual observation to full genetic sequencing—whatever it takes to identify the problem and suggest ways to improve the plant’s health.
From sample to solution
About 80% of the plants seen in the lab come from Maryland nurseries and growers that cultivate ornamental plants, from bedding flowers to landscape trees and ornamental grasses. Other clients include vegetable farms that produce crops such as tomatoes, pumpkins, watermelons and strawberries.
Although Fulladolsa and her team examine many different plants from varying environments, their diagnostic process always begins the same way: with careful observation.
“I’ve accepted clear plastic bags of pine needles and seen little spots on them, fungal fruiting bodies,” she explained, describing a previous case. “So, to make sure, I take it and put it under a microscope to confirm that.”
The lab’s diagnostic toolkit is extensive. The researchers might extract nematodes (microscopic worms that spread diseases), create moist chambers to promote fungal sporulation, extract and sequence DNA, or use polymerase chain reaction techniques to identify pathogens at the molecular level. Sometimes the answer is immediately visible to the naked eye; other times, it requires weeks of culturing and genetic analysis.
One of the lab’s recent cases put all the team’s skills to the test. A greenhouse reported troubling growth problems in its poinsettias, just a few weeks before the winter holidays. Some plants were stunted; others were yellowing. After a thorough phone consultation with the grower, Fulladolsa requested targeted samples and coordinated with an extension specialist who drove to the greenhouse to collect them.
Once the poinsettia patients arrived, Fulladolsa pulled them from their pots and triaged their symptoms. The roots were underdeveloped and covered in lesions—textbook signs of fungal infection. A quick slide under the microscope confirmed the diagnosis. The grower was then able to treat the remaining plants and salvage the season.
“Once we figure out the problem, we let the growers know immediately so that they can avoid the spread of a pathogen,” she explained. “We help salvage the plants that aren’t as far along yet and it can make a big difference.”
A lab that doubles as a classroom
Tara Dinh, a senior agricultural science and technology major, found herself drawn to the lab’s vigorous problem-solving process. On a field trip to western Maryland for a vegetable production class, she collected diseased tomato samples from an experimental plot and brought them back to campus. At the lab, she traced the damage on the tomatoes to thrips—tiny insects that vector devastating plant viruses.
“You could see all the disease on them,” Dinh recalled. “Thrips are so small, but their impact is very big. Tomatoes are grown all over Maryland, but they are very susceptible to thrips and the diseases they vector. Seeing that for myself and identifying the problems was extremely satisfying.”
Dinh’s experience in Fulladolsa’s lab confirmed her passion for the research and helped her decide to apply to graduate school programs in plant pathology. For the next step of her journey, Dinh won’t have to go far—she was accepted into the plant pathology track of UMD’s Plant Sciences M.S. program for next spring.
Reina Cabrera, a junior biological sciences major, found an even more unusual passion: nematodes. These microscopic roundworms can devastate plants and identifying them requires careful extraction and extensive anatomical knowledge. They fascinated Cabrera.
“When I came to this lab, I knew absolutely nothing about nematodes,” Cabrera said. “Then we found some nematodes in plant samples sent here, we learned how to fish them out of the samples, look at them under the microscope and try to identify them based on their anatomy. And after a while, I became really good at all of that.”
Cabrera’s unique talent at identifying nematodes on sight was so remarkable that the team dubbed her the lab’s nematode expert.
“Reina’s able to get them down to the genus,” Fulladolsa explained. “Sometimes I find myself asking her, ‘Wait, is that the one with the hooked tail?’ and she can confirm it instantly. Once we know which one it is, we get closer to pinpointing a diagnosis for a plant.”
With demand for the lab’s diagnostic services steadily increasing, Fulladolsa’s team is working to enhance its diagnostic capabilities by providing education on plant pathogens and developing high-throughput research protocols that can test 96 samples simultaneously.
“It’s important to increase the volume of ‘patients’ we see, especially because of the rise in invasive insect species and diseases in our area,” Fulladolsa noted. “Beech leaf disease and laurel wilt are both emerging threats. Each winter, I travel to county extension meetings across Maryland, teaching growers to recognize disease early and submit samples before problems spiral out of control.”
The lab is also expanding its collaborations with UMD’s Department of Entomology, working with Professor Paula Shrewsbury to identify insects in collected samples, monitor disease, and create outreach materials for scouts, farmers and growers.
It’s a lot for a lab that’s a year into its new chapter—but for Fulladolsa and her students, the hard work is worth it.
“Everything was very exciting this past year because everything was new for all of us,” Fulladolsa said. “I know about the pathogens, I know about the diseases—but maybe I've never actually seen them before. There were little finds that were really fascinating, even just looking at a particular fungal structure and having it look exactly like a textbook image under the microscope. That never gets old.”
