--- title: "When a Plant Disease Stumps Others, a UMD Lab Investigates" date: 2026-05-11T05:30:00-04:00 author: University of Maryland canonical_url: "https://today.umd.edu/when-a-plant-disease-stumps-others-a-umd-lab-investigates" section: Articles --- # When a Plant Disease Stumps Others, a UMD Lab Investigates *May 11, 2026* — by [Karen Shih ’09](/author/karen-shih) > UMD Research Changes Lives: Plant Diagnostic Lab Works to Identify, Prevent Disease Outbreaks in Maryland Agriculture, Green Industry *Plant Diagnostics Lab Fulladolsa 7 1920x1080 — Plant Diagnostic Lab Director Ana Cristina Fulladolsa (left) analyzes a plant sample with biochemistry major Suchitra Arun '28, one of four student lab assistants. (Photo by Mark Sherwood)* Baskets overflowing with fruit, sticky fingers and red-stained grins mark the sweet joy of strawberry season in Maryland. Whether it’s families with young kids or couples on dates, eager customers walk the long rows at pick-your-own farms every May and June, savoring the juicy, ripe fruits along the way. But an insidious rot, hidden beneath vibrant serrated leaves, could leave them all empty-handed. Greenery wilts, berries shrivel and eventually, whole plants die. Fingering a cause isn't as easy as plucking a berry, however. A variety of pathogens could be the culprit—and knowing which one is critical to applying the right treatment. That’s why last summer, a farm in distress turned to the University of Maryland’s Plant Diagnostic Lab, led by Director Ana Cristina Fulladolsa. She's the equivalent of TV's Dr. House for greenery across the state, taking on the toughest mysteries confounding nurseries, farmers and landscapers who help make up the $1.76 billion horticulture industry in Maryland. As a member of the National Plant Diagnostic Network, the lab also works closely with state and federal agencies to monitor new diseases and pests and prevent outbreaks. “Every day you're solving a puzzle,” said Fulladolsa, an assistant research professor in the Department of Entomology and Plant Science and Landscape Architecture. “It's great fun to be a diagnostician. With every sample is a new challenge and a new opportunity to learn something to help someone.” ## Digging into the problem In one corner of the lab, a single, spindly tree trunk juts out of a pot wrapped in a garbage bag. Atop a wooden table is an assortment of wan, squat evergreens with their roots exposed. Elsewhere, yellowed pine needles dry in a bag; petri dishes of brown leaves grow fuzzy white mold; a stem from a succulent awaits inspection beneath a microscope. These are all Fulladolsa’s patients. “Just like in a hospital or a clinic, we begin with triage,” said Fulladolsa, who has a team of four undergraduate interns. “What do we observe? What’s our primary hypothesis? What do we have to do next?” *Baskets of hanging flowers* *A strawberry plant sliced in half showing crown rot — A sliced-open strawberry plant showing crown rot.* ## Protecting the state—and beyond Whether as a stowaway egg mass on a container ship crossing the Pacific Ocean or as bacteria lingering on a guava brought back from a tropical resort, pathogens slip in daily that could threaten U.S. ecosystems and agriculture. To better track and stop the spread of these pests and diseases, UMD’s Plant Diagnostic Lab works with federal and state agencies, including participating in the National Plant Diagnostic Network, established after the Sept. 11 attacks to prevent bioterrorism. The network provides trainings, holds a national data repository and provides federal funding to its members as a first line of defense against outbreaks. *Dried leaves — Fire blight on an apple tree* *white and pink fungus culture in a petri dish — Culture of the fungus *Fusarium** *A parasite shown under a microscope — Nematode that causes beech leaf disease* In January, Fulladolsa was part of what she called “a true success story” when a central Maryland resident noticed that a grapefruit tree they had bought a few months earlier had started developing dark spots on its leaves. The resident sent photos of the ornamental tree in its pot to UMD Extension agent Amy Rembold, and the agent notified entomology Professor Paula Shrewsbury, who often works with Fulladolsa and looped in the Plant Diagnostic Lab. “It looked alarming to me, and the symptoms were a big red flag,” said Fulladolsa. She suspected it was citrus canker, a federally quarantined disease that has infected groves throughout the Florida and has no cure. She immediately sent the photos to Kim Rice, program manager in the Maryland Department of Agriculture, whose office collected the plant and visited the nursery where the tree was purchased. The state tested a sample, and a test in a U.S. Department of Agriculture lab definitively confirmed citrus canker—all within 20 days, a quick turnaround for this type of problem. UMD’s Plant Diagnostic Lab “serves as an extra eye for us,” said Rice. “We’ve always worked really closely with the university, and they are incredibly helpful and a great resource and partner.” While Maryland doesn’t have a citrus industry like Florida, containing the disease is critical because it can persist in the environment and spread easily through wind, rain and contaminated equipment. (Local ornamental orange blossom trees could still be affected.) And this constant communication Fulladolsa and her lab are at the center of means that when a disease with major ramifications for local plants emerges, everyone will be ready to act. “Early detection and monitoring is important,” said Fulladolsa. “Our services help safeguard our food and natural resources across the state and the country.” *Ana Cristina Fulladolsa uses a microscope to look at a plant* **Sidebar note:** **UMD Research Changes Lives** At the University of Maryland, scientists and scholars come together to spark new ideas, pursue important discoveries and tackle humanity's grand challenges—improving lives in our communities and across the globe. See more examples of how UMD research changes lives at [today.umd.edu/topic/research-impact](https://today.umd.edu/topic/research-impact). **Topics:** [Research](https://today.umd.edu/tags/research) **Tags:** [Entomology](https://today.umd.edu/topic/entomology), [Plant Science and Landscape Architecture](https://today.umd.edu/topic/plant-science-and-landscape-architecture), [Research Impact](https://today.umd.edu/topic/research-impact), [Research](https://today.umd.edu/topic/research) **Units:** [College of Agriculture and Natural Resources](https://today.umd.edu/topic/college-agriculture-and-natural-resources), [University of Maryland Extension](https://today.umd.edu/topic/university-of-maryland-extension), [College of Computer, Mathematical, and Natural Sciences](https://today.umd.edu/topic/college-computer-mathematical-and-natural-sciences)