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Now is the best time to test for Brown Root Rot

Early in the growing season is the best time for testing of alfalfa for brown root rot (BRR), caused by Phoma sclerotioides. The Plant Disease Diagnostic Clinic offers two types of testing for BRR; molecular PCR analysis and plant tissue isolation on growth media. Our most commonly requested testing method is molecular PCR analysis. The molecular analysis test is preferred because it can provide an answer much more quickly than isolation of the slow growing pathogen from tissue.

Pricing: DNA extraction and qPCR: $100; discounted fee for New York State growers: $80. Tissue Isolation: $50; discounted fee for New York State growers: $35. Combination of DNA and Tissue analyses: $140; discounted fee for NYS growers = $100.

Other Clinic Fees? Please go to the "Fees" link to see the current fee schedule and all the services offered.

Questions? Contact the staff of the CU-PDDC via Email, or see our sample submission instructions

The Plant Disease Diagnostic Clinic is a facility of the Section of Plant Pathology and Plant-Microbe Biology within the School of Integrative Plant Science at Cornell University. The Clinic provides fast and accurate plant disease diagnosis and up-to-date pest control recommendations for anyone from home owners to commercial growers. Services include analysis of plant material and soil for bacterial, fungal, viral, and nematode pathogen.


The Clinic promotes a "Test, Don't Guess" attitude. This is because we feel that knowing the pest affecting your plants and crops prior to treatment is essential for the best chances of recovery. The "Test, Don't Guess" policy allows for the appropriate selection and efficient use of control methods.

When sending a sample to the laboratory please include a Sample Submission Form. Please follow our collection tips when submitting samples! A sample that is improperly collected, packed, and/or shipped and arrives in poor shape is very difficult to diagnose.

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Comprehensive collection of plant pest factsheets.

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