Dr. Cheryl Blomquist

Plant Pest Diagnostics Branch, California Department of Food & Agriculture
3294 Meadowview Road, Sacramento, CA 95832-1448, U.S.A.
Office: 916-738-6707
Fax: 916-262-1190
Email: cblomquist@cdfa.ca.gov

Cheryl Blomquist

Senior Environmental Scientist - Supervisor

Curriculum Vitae


  • Doctor of Philosophy (Plant Pathology) - University of California, Davis. 2000.
  • Bachelor of Science (Biochemistry) - Washington State University, Pullman. 1981

Positions Held

  • 2015-present Senior Environmental Scientist (Supervisor), CDFA-PPD
  • 2011-2015 Senior Plant Pathologist (Supervisor), CDFA-PPD
  • 2004-2011 Senior Plant Pathologist (Diagnostician), CDFA-PPD
  • 2001-2004 Associate Plant Pathologist (Diagnostician), CDFA-PPD
  • Responsibilities:

    • Diagnose Phytophthora ramorum the causal agent of Sudden Oak Death for California’s fourteen infested counties.
    • Diagnose this disease and other diseases caused by Phytophthoras using symptomatic, morphological and molecular criteria and techniques.
    • Adapted an existing set of PCR primers for the diagnosis of P. ramorum. Screen more than 25,000 samples from nurseries and woodlands per year for the presence of this disease.
    • Diagnose diseases caused by Phytophthoras in samples submitted to the clinic.
    • Diagnose other diseases caused by fungi in woody plants and agricultural crops.
    • Give educational talks and training sessions to county biologists, foresters, nursery professionals and park workers about Sudden Oak Death.
  • 2000- 2001 Visiting Posdoctoral Scientist, Department of Plant Pathology, University of California, Davis. (Dr. Lynn Epstein, advisor)
  • Research project:

    • Study of the biology of Eutypa lata, pathogen of mature grapevines.
    • Use AFLP to genetically fingerprint isolates from infected mother plants from the Department of Viticulture and Enology to determine if Eutypa can be vegetatively transmitted.
    • Isolated Eutypa from naturally-infected grapevines, identified Eutypa isolates using mophological criteria and Eutypa-specific PCR.
    • Perform mating experiments using Eutypa isolates obtained from single ascospores from individual perithecia.
    • Performing experiments to determine if conidia produced by Eutypa actually serve as spermatia.
  • Other duties:

    • Support other laboratory projects by designing PCR primers and troubleshooting other lab member's experimental results.
  • 1993-2000 Graduate research assistant, Department of Plant Pathology, University of California, Davis. (Dr. Bruce Kirkpatrick, major professor)
  • Ph.D.dissertation title:

    • “Analysis of Phytoplasma-Infected Insect Vectors in Peach and Pear Orchards in California and Identification and Characterization of an Immunodominant Protein Gene from the Western X Disease Phytoplasma”
  • Field Research:

    • Collected and analyzed pear psylla monthly from 3 orchards in northern California to determine whether the number of psylla infected with the pear decline phytoplasma varied seasonally.
    • Compared the numbers of pear psylla detected by PCR versus those detected with hybridiation analysis.
    • Performed a study to evaluate the peach yellow leaf roll vector populations and to assess the control of peach yellow leaf roll in 3 Yuba county orchards using an insecticide treatment and a zinc defoliation treatment.
    • Evaluated the zinc treatment in preliminary experiments on healthy peach trees to see if the treatment affected bloom number, fruit size or yield.
  • Laboratory Research:

    • Cloned and sequenced an immunodominant protein gene from the Western X-disease phytoplasma using degenerate primers obtained from tryptic peptides derived from the purified protein.
    • Expressed the protein in E. coli, purified the expressed protein and showed that antibodies made to the expressed protein react with the native protein in the Western X phytoplasma.
  • Professional:

    • Presented research results at meetings of the American Phytopathological Society, the International Organization of Mycoplasmology, UC Davis' Plant Pathology's departmental seminar and laboratory meetings.
  • Other Duties:

    • Analyzed samples submitted by farm advisors and CDFA for phytoplasmas and reported results.
  • Techniques routinely performed:

    • PCR, both routine assays and primer design
    • DNA hybridization assays using radioisotopes
    • Agarose gel electrophoresis
    • DNA extraction techniques from both insects and plants
    • DNA quantitation using the Hoechst dye binding assay
    • Protein purification
    • SDS PAGE
    • Immunoaffinity chromatography
    • Antibody purification
    • Fab fragment production
    • Cloning
    • Southern blot analysis
    • ELISA
    • Dot blot analysis (both protein and DNA).
  • Greenhouse and insectary:

    • Maintained both leafhopper and pear psylla colonies.
    • Perform transmission experiments with both leafhoppers and psylla.
    • Stratify, plant and maintain pear seedlings and pear trees.
    • Plant and maintain celery for Colladonus montanus rearing.
    • Maintain cultures of phytoplasma strains in Catharanthus roseum by grafting.
    • Perform routine propagation of C. roseum by rooting cuttings.
  • 1989-1993 Staff Research Associate, Athena Neurosciences, South San Francisco, CA (Dr. Dale Schenk, supervisor)
  • Technical:

    • Characterize and evaluate monoclonal and polyclonal antibodies made in house using RIA, ELISA, immunoblot and immunoprecipitation techniques.
    • Designed and coordinated the purification of antibodies from ascites to extremely low pyrogen standards using FPLC and open column chromatography.
    • Developed ELISA’s for the measurement of Botulinum toxin, antibodies to Botulinum toxin serotype A and B, and alpha-1 antichymotrypsin.

Awards, Offices Held, Professional Memberships

  • Jastro Shields Grant 1997-1998
  • Dow Ellanco Student Award 1998
  • American Phytopathological Society membership
  • International Organization of Mycoplasmology membership
  • Department of Plant Pathology Students President, 1994-1995
  • Student-run Plant Disease Clinic Chair 1996-1997

Publications And Abstracts

  1. Blomquist, C.L., L.E. Yakabe, S. Rooney-Latham, N. McRoberts, C. Thomas. Detection of Phytophthora ramorum in Nurseries and Forest Lands in California in 2004 to 2009. (Accepted to Plant Disease 2015)
  2. Blomquist, C.L., S. Rooney-Latham, H.J. Scheck, K. Adler.  First Report of the Rust Uromyces plumbarius on Gaura lindheimeri in California. (Accepted to Plant Disease 2015)
  3. Frankel, S., Swiecki, T., Bernhardt, E., Rooney-Latham, S., and Blomquist, C. 2015. Pest Alert: Phytophthora tentaculata. [Online publication] USDA Forest Service, Pacific Southwest Research Station, Albany, CA. February 2015. Link
  4. Rooney-Latham, S. C.L. Blomquist, T. Sweicki, E.Bernhardt, S. J. Frankel. 2015. First detection in the US: new plant pathogen, Phytophhtora tentaculata, in Native Plant Nurseries and Restoration Sites in California. Native Plants 16:23-25.
  5. Blomquist, C.L., M. Scholler,.H.J. Scheck. 2015. Detection of Rust Caused by Tranzschelia mexicana on Prunus salicifolia in the United States. Plant Disease 99:1856.
  6. Blomquist, C.L., H.J. Scheck, P.W. Woods, and J.F. Bischoff.  2014. First detection of Puccinia ballotiflora on Salvia greggii Plant Disease 98:1270.
  7. Bilodeau, G.J., Martin F.N., Coffey, M.D., Blomquist, C.L. 2014. Development of a Multiplex Assay for Genus and Species-Specific Detection of Phytophthora based on differences in mitochondrial gene order. Phytopathology 104:733-748.
  8. Rooney-Latham, S., and C.L. Blomquist. 2014. First report of root and stem rot caused by Phytophthora tentaculata on Mimulus aurantiacus in North America. Plant Disease 98:996.
  9. Blomquist, C.L., H.J. Scheck, J. Haynes, P.W. Woods and J. Bischoff. 2014. First Published Report of Rust on White Alder Caused by Melampsoridium hiratsukanum in the United States. Plant Disease 98: 155.
  10. Serdani, M, S. Rooney-Latham, K.M. Wallis and C.L. Blomquist. 2013. First Report of Colletotrichum phormii Causing Anthracnose on New Zealand Flax in the United States. Plant Disease 97:1115.
  11. Rooney-Latham, S., E. Honeycutt, J. Ochoa, N.J. Grunwald, C.L. Blomquist. 2013. First Report of Camphor tree (Cinnamomum camphora) as a host of Phytophthora ramorum. Plant Disease 97:1377.
  12. Blomquist, C.L., L.E. Yakabe, M. Soriano, and M. Negrete 2012. First Report of Leaf Spot caused by Phytophthora taxon PGchlamydo on Evergreen Nursery Stock in California Plant Disease 96:1691.
  13. Blomquist, C.L., S. Rooney-Latham, M.C. Soriano, and J.C. McCarty 2012. First Report of Phytophthora ramorum Causing a Leafspot on Loropetalum chinense, Chinese Fringe Flower in California. Plant Disease 96: 1829.
  14. Kumagai, L.B., C.S. LeVesque, C.L. Blomquist, K. Madishetty, Y. Guo, P.W. Woods, S. Rooney-Latham, J. Rascoe, T. Gallindo, D. Schnabel, and M. Polek 2013. First Report of Candidatus Liberibacter asiaticus Associated with Citrus Huanglongbing in California.Plant Disease 97:283.
  15. Rooney-Latham, S., and C.L. Blomquist. 2012. First Report of Neofusicoccum nonquaesitum Causing Branch Cankers on Giant Sequoia (Sequoiadendron giganteum) in North America Plant Disease:96:1478.
  16. Rooney-Latham, S., C.L. Blomquist and H.J. Scheck 2011. First Report of Fusarium Wilt Caused by Fusarium oxysporum f.sp. passiflorae on Passion Fruit in North America. Plant Disease 95:1478.
  17. Blomquist, C.L. and C. Y. Warfield 2011. First Report of Ramularia didyma Causing a Leaf Spot on Ranunculus (Ranunculus asiaticus) Hybrids in California. Plant Disease 95:872.
  18. Blomquist, C.L., S. Rooney-Latham, J.L. Haynes, and H.J. Scheck 2011. First Report of Verticillium Wilt on Field-Grown Cosmos Caused by Verticillium dahliae in California. Plant Disease 95:361.
  19. Blomquist, C.L., S. Rooney-Latham, D.G. Fogle, and E.G. Simmons 2011. First Report of Embellisia hyacinthi causing a Leaf Spot and Bulb Skin Spot Disease on Scilla peruviana in California. Plant Disease 95:356.
  20. Blomquist, C.L., and I. D. Greene 2011. First Report of Botrytis hyacinthi on Pineapple Lily in California. Plant Disease 95: 224.
  21. Riley, K.L, Chastagner, G.A., and Blomquist C. 2011. First report of Phytophthora ramorum Infecting Grand Fir in California. Online. Plant Health Progress doi: 10.1094/PHP-2011-0401-01-BR.
  22. Rooney-Latham, S., C.L. Blomquist, and J. Turney 2009. First Report of Downy Mildew Caused by Peronospora trigonellae on Fenugreek (Trigonella foenum-graecum) in the United States Plant Disease 93:1349
  23. Blomquist, C.L., S. Rooney-Latham, and P.A. Nolan. 2009. First Report of Downy Mildew on Field-Grown Sweet Basil Caused by a Peronospora sp. in San Diego County, California. Plant Disease 93: 968.
  24. Blomquist, C.L., J.M. McKemy, M.C. Aime, R.W. Orsburn, and S.A. Kinnee 2009. First report of Bamboo Rust Caused by Kweilingia divina on Bambusa domestica in Los Angeles County, California Plant Disease 93: 201.
  25. Rooney-Latham, S., C.L. Blomquist, T. Pastalka, L. Costello 2009. Collar Rot on Italian Alder Trees in California Caused by Phytophthora siskiyouensis. Online. Plant Health Progressdoi:1094/PHP-2009-0413-01-RS.
  26. Martin, F.N., M.D. Coffey, K. Zeller, R.C. Hamelin, P. Tooley, M. Garbelotto, K.J.D. Hughes T. Kubisiak, G.J. Bilodeau, L. Levy, C. Blomquist, and P.H. Berger 2009. Evaluation of Molecular Markers for Phytophthora ramorum Detection and Identification: Testing for Specificity Using a Standardized Library of Isolates. Phytopathology 99: 390-403.
  27. Warfield, C.Y., C.L. Blomquist, and E.E. Lovig 2009. First Report of Downy Mildew on Nursery-Grown Hellebore Caused by Peronospora pulveracea in California. Plant Disease 93: 319.
  28. Yakabe, L.E., Blomquist, C.L., S.L. Thomas, and J.D. MacDonald 2009. Identification and Frequency of PhytophthoraSpecies Associated with Foliar Diseases in California Ornamental Nurseries Plant Disease 93: 883-890.
  29. Grünwald N.J., Goss E.M., Larsen M.M., Press C.M., McDonald V.T., Blomquist C.L., and Thomas S.L. 2008. First report of the European lineage of Phytophthora ramorum on Viburnum and Osmanthus spp. in a California nursery. Plant Disease 92: 314.
  30. Blomquist, C.L., S.L. Thomas, J.M. McKemy, P.A. Nolan, and M. Luque-Williams 2007. First Report of Uromyces transversalis, Causal Agent of Gladiolus Rust, in San Diego County, California. Plant Disease 91:1202.
  31. Schubert, T.S., Rizvi, A., Brown, L.G., Blomquist, C., Killgore, E. 2007. First occurrence of gladiolus rust caused by Uromyces transversalis in the United States Phytopathology 97:S105.
  32. Yakabe L.E., Blomquist, C.L., Thomas S.L., MacDonald J.D. 2007. Identification and frequency of Phytophthora species causing foliar diseases in California ornamental nurseries. Phytopathology 97:S126.
  33. Donahoo, R.S., Moulton, J.K., Blomquist, C.L., Thomas, S.L., Cooke D.E.L. and Lamour, K.H. 2006. Phytophthora foliorum sp. nov., a new species causing leaf blight of azalea. Mycological Research 110:1309-1322.
  34. Hostert, N.D., Thomas, S.L., Fogel, D.L, Blomquist, C.L. and Davis R.M. 2006. First report of Ramularia carthami, causal agent of Ramularia leaf spot of Safflower in California. Plant Disease 90:1260.
  35. Tjosvold, S.A. Chambers, D.L., Thomas, S.L. and Blomquist, C.L. August 25, 2005. First report of Phytopththora ramorum infecting Camellia flower buds in North America. Online. Plant Health Progress doi: 10.1094/PHP-2006-0825-01-BR.
  36. Tjosvold, S.A., Buermeyer K.R., Blomquist, C.and Frankel S. 2005. Nursery Guide for Diseases of Phytophthora ramorum on Ornamentals: Diagnosis and Management. Division of Agricultural and Natural Sciences Publications. Publication #8156
  37. Blomquist, C., Irving, T., Osterbauer, N., Reeser, P. July 28, 2005. Phytophthora hibernalis: a new pathogen of Rhododendron and evidence of cross amplification with two PCR detection assays for Phytophthora ramorum. Online. Plant Health Progress doi: 10.1094/PHP-2005-0728-01-HN.
  38. Martin, F. N., Tooley, P.W. and Blomquist, C.L. 2004. Molecular detection of Phytophthora ramorum the causal agent of Sudden Oak Death in California and two additional species commonly recovered from diseased material. Phytopathology 94:621-631.
  39. Blomquist, C.L. Kubisiak, T. 2003. Laboratory diagnosis of Phytophthora ramorum from field samples. Sudden Oak Death Online Symposium April 21-May 12, 2003 Freely available.
  40. Blomquist C.L., Fischer, K. and Fry, M. 2002. Can vertebrates transmit viable Phytophthora ramorum spores—data from the lab. Abstract for the Sudden Oak Death Science Symposium Dec. 15-18, Monterey, California.
  41. Blomquist, C. L. and Kirkpatrick B. C., 2002. Frequency and seasonal distribution of pear psylla infected with the pear decline phytoplasma in California pear orchards. Phytopathology 92: 1218-1226.
  42. Blomquist, C.L. and Kirkpatrick, B.C., 2002. Identification of phytoplasma taxa and insect vectors of peach yellow leaf roll disease in California. Plant Disease: 86:759-763.
  43. Blomquist, C.L. Aster yellows and Beet Leafhopper-Transmitted Virescence Agent Yellows in Compendium of Umbelliferous Crop Diseases, R.M. Davis, editor, 2002.
  44. Blomquist, C.L. and Kirkpatrick, B.C., 2001. An immunodominant membrane protein gene from the X-disease phytoplasma is distinct from those of other phytoplasmas. Microbiology 147:571-580.
  45. Blomquist, C.L. and Kirkpatrick, B.C., 1998. Infectivity of phytoplasma insect vectors collected in pear decline and peach yellow leaf roll-infected orchards in northern California. Abstract for the IOM meetings, Sydney, Australia, July 1998.
  46. Blomquist, C.L. and Kirkpatrick, B.C., 1997. Infectivity of pear psylla (Cacopsylla pyricola Foerster) collected from pear decline infected trees. Phytopathology 87:S9.
  47. Smart, C.D., Schneider, B., Blomquist, C. L., Guerra, L.J., Harrison, N. A., Ahrens, U., Lorenz, K-H, Seemuller, E., Kirkpatrick, B. C., 1996. Identification of phytoplasma-specific PCR primers obtained from the 16S/23S rRNA spacer region. Applied and Environmental Microbiology 62: 2988-2993.