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PPDC Plant Pathology lab

Plant Pathology Laboratory Overview

Diagnostic services provided by the Plant Pathology Laboratory included:

  1. Diagnosis of samples submitted by pest prevention programs by state, county, and federal agencies, as well as academic and public sources.
  2. Diagnosis of samples submitted by the Fruit and Nut Tree and Grapevine Improvement Advisory Board to be tested for Prunus necrotic ringspot and prune dwarf viruses using enzyme-linked Immunosorbent assay (ELISA).
  3. Diagnosis of grapevine samples submitted by the Grapevine Registration and Certification Program for ELISA testing for the presence of grapevine fanleaf and leaf roll viruses.
  4. Diagnosis of plant samples specifically for Piece’s Disease, as part of the Statewide Glassy Wing Sharpshooter and Pierce’s Disease Project.
  5. Diagnosis of samples as part of Homeland Security’s National Plant Diagnostic Network (NPDN).
  6. Diagnosis of Seed samples examined and tested to determine phytosanitary seed health compliance prior to export.
  7. Diagnosis of miscellaneous plant samples submitted by individual farmers, Pest control advisors, U.C. cooperative extension agents, nurserymen, arborists, homeowners, government municipalities, educational institutions, and others.
  8. Diagnosis of samples collected for various plant disease surveys including Plum Pox, Sudden Oak Death, Citrus Canker, Rice Diseases, and others.

Of the samples handled by the plant pathology laboratory, some involve known fungal pathogens, some involve viral or phytoplasma pathogens, some involve bacterial pathogens, and some samples have plant disorders that have a physiological, chemical, or genetic cause. In addition, many samples have no detectable pathogen and require further sampling and or investigation. And lastly, some samples are the results of routine field inspections performed to confirm the pest-cleanliness of the commodity for various phytosanitary purposes, including export.

In addition, the Plant Pathology staff serves as a scientific resource to the Department of Food and Agriculture, County Departments of Agriculture, and others.

Diagnostics Responsibilities:

Scientist Diagnostic Responsibilities
Dr. Cheryl Blomquist Mycology
Lucita Kumagai Bacteriology
Dr. Suzanne Rooney Latham Mycology
Dr. Tongyan Tian Virology
Dr. Yunping Zhang Virology, Seed Health Testing