Plant Problem Diagnostics

Sending Samples to the Laboratory & Links to Diagnose Problem Plants

Integrated Pest Management (IPM) looks at crops as part of a larger ecosystem and attempts to restore balance within that system by considering all options before taking action. Accurate pest identification, diagnosis and monitoring are crucial to IPM strategies, which integrate cultural, biological and chemical solutions to grow a crop with minimal use of pesticides.The following links provide information to help diagnose plant problems.

Floriculture Diagnostic Services New Lab Location 2011!!

The Floriculture Disease Diagnostic Lab has a new location. It is located off-campus:

UMass Extension Plant Diagnostic Lab
101 University Drive-Suite A7
Amherst, MA 01002

Parking is free and easily accessible to the lab on the first floor.

Commercial flower growers who have a problem with their crop and are in need of diagnostic services should contact one of the following specialists directly:

Diseases - Dr. Rob Wick, Bess Dicklow, Tina Smith, Paul Lopes
Insects - Tina Smith, Paul Lopes
Plant nutrition - Dr. Douglas Cox

How to Send Samples to the Diagnostic Laboratory

If you do not know the general cause of the problem, contact Dr. Rob Wick, Bess Dicklow, Tina Smith or Paul Lopes. The fee for diagnosis is $50 per sample. Make check payable to "University of Massachusetts". Upon reaching a conclusion, the lab will call or send a report on the diagnosis and recommendations. Always call Dr. Wick (413) 545-1045 or Bess Dicklow ((413-545-3209) first to see if sending a specimen is necessary, or to inform them that one is being sent. Samples should be hand delivered if possible or sent overnight mail along with this form:

Plant Diagnostic Form

Print and complete this form and include with each sample. Send several plants or leaves showing a range of symptoms that are representative of the problem. If a specimen can be delivered to the lab in less than 48 hours, it can be placed in a plastic bag. Do not add water. When entire plants are sent, wrap roots and attached soil in a plastic bag and secure to the stem with a twist tie. Avoid sending plant material that is completely dead. See more details below.

Send samples to:
Bess Dicklow
UMass Extension Plant Diagnostic Lab
101 University Dr. - Suite A7
Amherst MA 01002

Guidelines for Taking Samples

Submit as much of the plant as possible.
The accuracy of a disease diagnosis can only be as good as the sample provided. To provide a good sample, be sure that the sample contains the right part of the plant. Symptoms may appear in parts of the plant that are not infected with the pathogen. For this reason, if possible, submit as much of the plant as possible. Ideally, this would be an intact plant.

Send several plants with a range of symptoms.
Secondly, the samples must be fresh and in good condition. Dead plants tell no tales. Due to secondary infections in extremely decayed plants, it is difficult to determine which organism may have created the problem in the first place. If possible, send in several plants with a range of symptoms from moderate to severe.

Keep leaves dry and free of soil.
Wet samples with soil on the leaves promote the growth of secondary pathogens and create problems that did not exist when the sample was originally collected. Do not ever add water to your sample.

Hand deliver or ship overnight.
Rapid delivery may be critical for an accurate diagnosis. Samples that take a long time to get to the diagnostic lab have a greater chance of decaying or drying up making diagnosis difficult. You may want to hand deliver the sample to the lab. If you are too far away from the lab, then ship the sample overnight. The diagnostic laboratory is closed over the weekend and you may not want to ship the sample on Friday or during a holiday. Call Bess at the UMass diagnostic lab prior to shipping to make arrangements for receiving the package.

How to select samples from plants with the following symptoms:

Leaf spots and Blights
Select leaves which show a range of symptom development. Place leaves between paper towels or sheets of paper to keep leaves dry. Place the package in a plastic bag, and then into the envelope for mailing. Never wrap leaves in wet paper towels.

Stem Cankers
When a canker occurs on a large plant, cut a section of the stem with the symptoms, wrap in newspaper and place in a plastic bag for mailing. If the plants are small (1 foot or less), shake the soil from the roots, wrap in newspaper and put into a plastic bag for mailing.

Wilt, Crown rot or Root rot
If the plants are 1 foot or less, include the entire plant. Include the root system with the plant, leaving the growing media on the roots. Place the root ball into a plastic bag and tie off at the crown to keep the media off the foliage. If the plants are large, send a portion of the plant that includes the infected tissue. For wilt diseases, include the lower stem tissue and roots.

Poor growth, Defoliation, Scorch
These symptoms are usually caused by nutritional or environmental factors. They may also be the result of root rot or vascular disease. Collect a specimen as for wilt (see above); be sure to also submit a soil sample to a soil test laboratory.

The following links provide information to help diagnose plant problems.

Photo Library
Photo Library - (UMass and UConn partnership) Pictures and descriptions of greenhouse plant problems that supplement the New England Pest Management Guide.

Insects, Mites & Diseases (Management)

New England Greenhouse Floriculture Guide (Order form) Descriptions, lifecycles and Management
Pest Management and Identification UC Davis

Diseases
Photo Library - Disease section
Plant Pathology Fact Sheets Penn State
Fact Sheets on Diseases UC Davis
Agdia Test Kits and Diagnostic Services Disease test kits are sold for on site disease detection
Hydros Inc Disease test kits are sold for on site disease detection

Insects, Mites
Photo Library - Insects, Mites section
Free Insect Identification (Send samples to USDA lab)
A Guide to Insects and Related Pests of Floricultural Crops in New England Contains pictures and lifecycles of greenhouse pests, available from the UMass Exension Bookstore
Fact Sheets on Insects University of Massachusetts

Plant Nutrition
Photo Library - Nutritional Disorders section
Nutrient Deficiency Symptoms North Carolina State University

Cultural Problems
Photo Library - Cultural Problems section (ie. Injury caused by oedema, ethylene, heat, cold, chemical)
Symptoms of Growth Regulator Overdose North Carolina State University