Diagnosing Virginia’s plant problems: From symptom to solution  

The Plant Disease Clinic provides diagnostic services to Virginians for sustainable, effective management of plant diseases.

By Julie Shlisky

The Virginia Tech Plant Disease Clinic, housed within the School of Plant and Environmental Sciences, offers diagnostic services and pathogen testing to Virginians across the state.

Diagnostic results are provided to clients along with appropriate management recommendations to ensure the most effective and sustainable tactics are used to manage plant disease as well as abiotic problems, such as environmental stress, nutrient deficiencies, and poor soil drainage.

“Diagnosis is at the core of effective plant health management,” said clinic Director Lina Rodriguez Salamanca.

Clients such as crop producers, nursery, greenhouse and other specialty crop growers, landscapers, or homeowners can expect diagnostic results in 3 to 14 days, depending on the tests needed. Small fees associated with the service ensure the clinic’s long-term sustainability.

“The real value to clients comes in our management recommendations,” Rodriguez Salamanca said. “We distinguish between abiotic problems and infectious diseases to provide targeted, effective, and sustainable solutions.”

Recommendations may include practices such as improving soil nutrition, adjusting irrigation, pruning, sanitation, and crop rotation. When pesticides are warranted, recommendations are based on Virginia Cooperative Extension (VCE) plant management guides developed by VCE specialists statewide.

The Plant Disease Clinic is also a resource for Extension agents and Master Gardeners for plant diagnostics and integrated pest management. If a plant problem cannot be identified by a VCE agent or Master Gardener volunteer, agents can facilitate plant sample submissions to the clinic so diagnosticians there can test for pathogenic fungi, bacteria, nematodes, viruses, and investigate abiotic problems.

“Extension is a conduit between the community and this professional resource, helping to access testing services, interpret results, and fielding follow-up questions,” said Nick Saylor, Extension Master Gardener coordinator. “We educate our staff and Master Gardeners using case studies from the clinic.”

The Plant Disease Clinic works closely with both the Virginia Tech Insect Identification Lab and Nematology Lab to accurately identify the cause of plant symptoms, since many insect and nematode problems mimic plant disease symptoms or occur in conjunction with disease. Clinic diagnosticians also consult with VCE field crop, nursery, greenhouse, and other specialty crop experts for assistance identifying abiotic problems to ensure the best management strategy is recommended to clients.

Survey results from clients who submitted plant samples to the Plant Disease Clinic in 2024 showed that approximately 70% of respondents said they understood their problem better and reported increased crop quality.

“The Clinic is where we turn to solve complex issues,” Saylor said. “We have long standing relationships with homeowners, commercial operations, landscape, and lawn and turf clients who value the lab as a resource. Having the backing of a world class lab increases our credibility, so the community is more apt to seek us out when they have a problem.”

Service labs like the Plant Disease Clinic are front-line detectors for the early spread of new diseases, especially since insect damage, abiotic disorders, and disease can look alike.

“Recently, a client sent in a sample of a plant in decline, and no disease was detected,” Saylor said. “The clinic connected with the nematode lab, and together they found an atypical nematode unusual to our region. It could potentially be an emerging issue that now we’re aware of.”

The clinic serves a wide range of clients who submit a variety of plant types and can provide diagnostic testing beyond what is available at Virginia’s Agricultural Research and Extension Centers (ARECs), which focus on regional crops.

Campus and AREC research is on the front line, usually focused on novel regional problems Virginia growers might face within their individual specialty crops. The Eastern Shore AREC focuses on issues encountered by vegetable and small grain growers, while Tidewater AREC’s Plant Diagnostic Clinic focuses on disease and nematode management in corn, cotton, peanuts, and soybeans. 

The Plant Disease Clinic collaborates with AREC specialists, supporting their regional commodity work with a shared laboratory management system and advanced diagnostic tools. Samples may be submitted through Extension offices, agricultural and natural resources agents, or directly to the Plant Disease Clinic.