Tim Paulitz

Tim Paulitz

Adjunct FacultyAdjunct Professor 509-335-7077 Information Technology Building Vogel PBS 324 (lab)

Research Specialty and Interests

My program focuses on the ecology, epidemiology, and management of root diseases in cereal-based cropping systems, including wheat, barley and Brassica. I have also investigated the core microbiome of wheat and how rotation crops affect the wheat microbiome. I examined how grower inputs such as glyphosate, lime, tillage, and biosolids affect the soil microbiome.  I am currently looking at how the soil and rhizosphere microbiome of wheat affect soil and plant health, and the correlations between fungal and bacterial communities and crop yield.

Professional Experience and Activities


2000-present. GS 15.  USDA-ARS Wheat Health, Genetics, and Quality Research Unit, Pullman, WA.  Research Plant Pathologist.  Soilborne fungal and nematode diseases of wheat, barley, canola, legumes and other rotation crops. Epidemiology, ecology, detection and quantification of soilborne pathogens. Soil and root microbiomes in wheat cropping systems.

1989-2000 Dept. Plant Science, Macdonald Campus of McGill University, Ste. Anne de Bellevue, Quebec, Canada. Assistant and Associate Professor.  Plant pathology of cereal, fruit, vegetable crops and greenhouse crops. Mycology, ecology, epidemiology.

1987-1989. USDA-ARS Horticultural Research Laboratory, Postdoctoral Research Associate.  Biological control of fungal diseases with antagonistic bacteria and interactions with vesicular-arbuscular mycorrhizal fungi.

1984-1987. Department of Plant Pathology and Weed Science, Colorado State University. Visiting assistant professor.  Biological control of greenhouse crops.


  • Section Editor, Canadian Journal of Plant Pathology, 2019-present
  • Editor-in-Chief, American Phytopathological Society Press, 2012-2016
  • Fellow, American Phytopathological Society, 2012-2016
  • Associate Editor-in-Chief, American Phytopathological Society Press, 2007-2012
  • Senior Editor, American Phytopathological Society Press, 2004-2007
  • Collaborator with CIMMYT Global Initiative on Wheat Root Health in Rainfed System, 2005-present
  • Member, secretary, and chair of W-3147 Biological Control of Soilborne Pathogens Multistate CSREES project, 2002-present
  • Member of U.S. Wheat and Barley Scab Initiative Review Panel, 1999-2002
  • Section Editor, Canadian Journal of Plant Pathology, 2001-present
  • Section Editor, Plant and Soil, 1998-2002
  • Senior Editor, Phytopathology, 1994-1997
  • Associate Editor, Phytopathology, 1991-1994

From 1990-2000, I supervised to completion 18 MSc students, 4 PhD students, and 5 postdoctoral researchers.  From 2000-2020, as an adjunct professor in the Dept. of Plant Pathology at Washington State University, I have supervised or co-supervised 9 PhD and 3 MSc students. I also served on thesis committees of over 50 MSc and PhD students.

Awards, Honors, and Memberships

  • California Regents Graduate Fellowship 1983. 
  •  Myron Winslow Scholarship, 1982. 
  • Certificate of Appreciation for Senior Editor, Phytopathology, 1997. 
  • Certificate of Appreciation, Canadian Phytopathological Society for Local  
  • Arrangements Chair, 1999 APS/CPS meeting. 
  • Certificate of Appreciation, Canadian Phytopathological Society, Junior and Senior Councillor, 2000. 
  • Pacific West Area USDA-ARS Outreach Award, 2008.
  • USDA-ARS National EEO/CR Outreach Award, Non-Supervisory Scientist Category,  2008. 
  • Fellow of the American Phytopathological Society, 2009. 
  • Member of American Phytopathological Society, Canadian Phytopathological Society, Mycological Society of American and American Society of Microbiology.  


(More than 175 refereed publications over career, 124 other publications, 20 book chapters and over 80 abstracts).  Refereed publications dealing with soil or plant health for the last 5 years are presented.

  • Jaaffar, A.M., Paulitz, T.C., Schroeder, K.L., Thomashow, L.S., Weller, D.M. Molecular characterization, morphological characteristics, virulence and geographic distribution of Rhizoctonia in the Inland Pacific Northwest. Phytopathology 106: 459-473. 2016.
  • Mahoney, A., Babiker, E., Paulitz, T., See, D., Okubara, P.A. and Hulbert S. Characterizing and mapping resistance in synthetic-derived wheat to Rhizoctonia root rot in a green bridge environment. Phytopathology 106:1170-1176. 2016.
  • Poudel, A., Jumpponen, A., Schlatter, D., Paulitz, T. C., McSpadden-Gardener, B., Kinkel, L. L. and Garrett, K. A.    Microbiome networks: A systems framework for identifying candidate microbial assemblages for disease management.  Phytopathology 106:1083-1096. 2016.
  • Thompson, A.L., Smiley, R.W., Paulitz, T.C., Garland Campbell, K.A. 2016. Identification of resistance to Pratylenchus neglectus and thornei in Iranian landrace accessions of wheat. Crop Science 56 :654-672. 2016.
  • Aujla, I. and Paulitz, T. C. An improved method for establishing accurate water potential levels at different temperatures in growth media. Frontiers in Microbiology. doi: 10.3389/fmicb.2017.01497. 2017. (Corresponding author)
  • Gargouri, S., Berraies, S., Gharbi, M. S., Paulitz, T. Murray, T. D. and Burgess, L. W. Occurrence of sclerotinia stem rot of fenugreek caused by Sclerotinia trifoliorum and sclerotiorum in Tunisia. European Journal of Plant Pathology 149: 587-597. 2017.
  • Jaaffar, K.M., Parejko, J.A., Paulitz, T.C., Weller, D.M., Thomashow, L.S. Sensitivity of Rhizoctonia isolates from the Inland Pacific Northwest of the United States to phenazine-1-carboxylic acid and biological control by phenazine-producing Pseudomonas Phytopathology. 107: 692-703. 2017.
  • Paulitz, T. C., Knerr, A. J., Carmody, S. M., Schlatter, D., Sowers, K., Derie, M. L., du Toit, L. J. First report of Leptosphaeria maculans and Leptosphaeria biglobosa, causal agents of blackleg, on canola in Washington State.  Plant Disease 101: 504-505. 2017. (Corresponding author)
  • Poudyal-Sharma, D., Schlatter, D., Yin, C. T. Hulbert, S. and Paulitz, T. C. Long-term no-till: a major driver of fungal communities in dryland wheat cropping systems. PloS One 12: 10.1371/journal.pone.018611. 2017. (Corresponding author)
  • Schlatter, D. C., Yin, C., Hulbert, S. Burke, I. and Paulitz, T. Impacts of repeated glyphosate use on wheat-associated bacteria are small and depend on glyphosate use history.  Applied and Environmental Microbiology 83: DOI: 10.1128/AEM.01354-17. 2017 (Corresponding author)
  • Schlatter, D., Kinkel, L., Thomashow, L., Weller, D. and Paulitz, T. C. Disease suppressive soils: New insights from the soil microbiome.  Phytopathology 107: 1284-1297. 2017. (Corresponding author)
  • Schlatter, D. C., Yin, C., Burke, I., Hulbert, S. and Paulitz, T. C. Location, root proximity, and glyphosate-use history modulate the effects of glyphosate on fungal community networks of wheat.Microbial Ecology 2018 (Corresponding author)
  • Thompson, A.L., Mahoney, A.K., Smiley, R.W., Paulitz, T.C., Hulbert, S., Garland Campbell, K.A. Resistance to multiple soil-borne pathogens of the Pacific Northwest is collocated in a wheat recombinant inbred line population. G3, Genes/Genomes/Genetics. 7: 1109-1116. 2017.
  • Yin, C., Schlatter, D., Schroeder, K., Mueth, N., Prescott, Dhingra, A., Hulbert, S. and Paulitz, T. C. Bacterial communities on wheat grown under long-term conventional tillage and no-till in thePacific Northwest of the US.  Phytobiomes 1: 83-90. 2017. (Corresponding author)
  • Schlatter, D.C., Schillinger, W.F., Bary, A.I., Sharratt, B.S., Paulitz, T.C. Biosolids and conservation tillage: Impacts on soil fungal communities in dryland wheat-fallow cropping systems. Soil Biology and Biochemistry. 115:556-567. 2017. (Corresponding author)
  • Mahoney, A.K., Babiker, E.M., See, D.R., Paulitz, T.C., Okubara, P.A., Hulbert, S.H. Analysis and mapping of Rhizoctonia root rot resistance traits from the synthetic wheat (Triticum aestivum ) line SYN-172. Molecular Breeding. https://doi 10.1007/s11032-017-0730-9. 2017.
  • Schillinger, W., Paulitz, T.C. Canola versus wheat rotation effects on subsequent wheat yield. Field Crops Research. 223:26-32. 2018.
  • Kandel, S. L, Smiley, R. W., Garland-Campbell, K., Elling, A. A. Huggins, D. and Paulitz, T. Spatial distribution of root lesion nematodes (Pratylenchus) in a long-term no-till cropping system and their relationship with soil and landscape properties. European Journal of Plant Pathology 150: 1011-1021. 2018. (Corresponding author)
  • Schlatter, D.C., Burke, I., Paulitz, T.C. Succession of fungal and oomycete communities in glyphosate-killed wheat roots. Phytopathology. 108:582-594. 2018. (Corresponding author)
  • Schlatter, D.C., Schillinger, W.F., Bary, A.I., Sharratt, B.S., Paulitz, T.C. Dust-associated microbiomes from dryland wheat fields differ with tillage practice and biosolids application. Atmospheric Environment. 185:29-40. 2018. (Corresponding author)
  • Schlatter, D.C., Kahl, K., Carlson, B.R., Huggins, D.R., Paulitz, T.C. Fungal community composition and diversity vary with soil depth and landscape position in a no-till wheat-based cropping system. FEMS Microbiology Ecology. (Corresponding author)
  • Hansen, J. C., Schillinger, W. F., Sullivan, T. S. and Paulitz, T. C. Rhizosphere microbial communities of canola and wheat at six paired field sites.  Applied Soil Ecology: 130:185-193. 2018.
  • Gebremariam, E. S., Sharma-Poudyal, D., Paulitz, T. C. Erginbas-Orakci, G., Karakay, A., and Dababaat, A. A. Identity and pathogenicity of Fusarium species associated with crown rot on wheat (Triticum) in Turkey. European Journal of Plant Pathology 150: 387-399. 2018.
  • Schroeder, K. L., Schlatter, D. C. and Paulitz, T. C. Location-dependent impacts of liming and crop rotation on bacterial communities in acid soils of the Pacific Northwest.  Applied Soil Ecology 130: 59-68.  (Corresponding author)
  • Knerr, A. J., Wheeler, D., Schlatter, D., Sharma-Poudyal, D., Du Toit, L. and Paulitz, C. Arbuscular mycorrhizal fungal communities in organic and conventional onion crops in the Columbia Basin of the Pacific Northwest, USA.  Phytobiomes 2: 194-207.  2019. (Corresponding author)
  • Hansen, J.C., Schillinger, W., Sullivan, T., Paulitz, T.C. Soil microbial biomass and fungi reduced with canola introduced in long-term monoculture wheat rotations. Frontiers in Microbiology. 10:1488.
  • Freed, G., Schlatter D., Paulitz, T. and Dugan, F. Mycological insights into wetland fungal communities: The mycobiome of Camassia in the Pacific Northwest. Phytobiomes Journal doi. 10.1094/PBIOMES-04-19-0022-R (Corresponding author)
  • Schlatter, D. C., Baugher, C. M., Kahl, D. Huggins, D. R., Johnson-Maynard, J. and Paulitz, T. C.Bacterial communities of soil and earthworm casts of native Palouse Prairie remnants and no-till wheat cropping systems. Soil Biology and Biochemistry. 2019. (Corresponding author)
  • Wen, N., Manning-Thompson, Y., Garland Campbell, K.A., Paulitz, T.C. Distribution of cereal cyst nematodes (Heterodera avenae and filipjevi) in Eastern Washington State. Plant Disease. 2019. (Corresponding author)
  • Schlatter, D.C., Paul, N.C., Shah, D.H., Schillinger, W.F., Bary, A.L., Sharratt, B.S., Paulitz, T.C.Biosolids and tillage practices influence soil bacterial communities in dryland wheat. Microbial Ecology. 2019. (Corresponding author)
  • Schlatter, D.C., Reardon, C.L., Maynard-Johnson, J.L., Brooks, E., Kahl, K.B., Norby, J., Huggins, D.R., Paulitz, T.C. Mining the drilosphere: bacterial communities and denitrifier abundance in a no-till wheat cropping system. Frontiers in Microbiology. 10:1339. 2019. (Corresponding author)
  • Kim, D. R., Cho, G., Jeon, C. W., Weller, D. M., Thomashow, L. S., Paulitz, T. C and Kwak, Y. S. A mutualistic interaction between Streptomyces bacteria, strawberry plants and pollinating bees Nature Communications. DOI: 10.1038/s41467-019-12785-3.
  • Carter, A. H., Allan, R. E., Shelton, G. B., Burke, A. B., Balow, K. A., Hagemeyer, K. E., Chen, X. M., Engle, D., Garland-Campbell, K. A., Morris, C. F., Murray, T. D., Paulitz, T. C., Clare, S. J. and Klarquist, E. F ” How “Madsen” has shaped Pacific Northwest wheat and beyond. Journal of Plant Registrations. DOI: 10.1002/plr2.20049. 2020.
  • Basaid, K., Cheblia, B., Mayad, E.H., Furze, J. N., Bouharroud, R., Krierd, F., Barakata, M. and Paulitz, T. C. Biological activities of essential oils and lipopeptides applied to control plant pests and diseases: A review. International Journal of Pest Management. org/10.1080/09670874.2019.1707327. 2020.
  • Schlatter, D., Yin, C., Hulbert, S. and Paulitz, T. C. Core rhizosphere microbiomes of dryland wheat are influenced by location and land use history. Appl Environ Microbiol 86:e02135-19. .02135-19. 2020.
  • Schlatter, D., Schillinger, W., Hansen, J, Sullivan, T. and Paulitz, T. C. Common and unique rhizosphere microbial communities of wheat and canola in a semiarid Mediterranean environment. Applied Soil Ecology 144: 170-181. DOI: 10.1016/j.apsoil.2019.07.010 2020. (Corresponding author)
  • Ozer, G., Imren, M., Bayraktar, H. Paulitz, T. C., Muminjanov, J. and Dababat, A. A. First report of Fusarium hostae causing crown rot on wheat in Azerbaijan. Plant Disease 103: 3278-3279. DOI: 10.1094/PDIS-05-19-1035-PDN. 2020.
  • Ozer, G., Alkan, M., Imren, M., Muminjanov, H. Paulitz, T. C. and Dababat, A. A. Identity and pathogenicity of fungi associated with crown and root rot of dryland winter wheat in Azerbaijan. Plant Disease 2020. (Corresponding author)
  • Dababat, A. A., Imren, M., Ozer, G., Mokrini, F. Duman, N. and Paulitz, T. Genetic and pathogenic variation in Heterodera latipons populations from Turkey. Nematology: 23:46-56
  • Yin, C., McLaughlin, K., Paulitz, T. C., Kroese, D. R. and Hagerty, C. H. Population dynamics of wheat root pathogens under different tillage systems in Northeast Oregon.  Plant Disease: 104:2649-2657
  • Schlatter, D., Kahl, K., Carlson, B., Huggins, D. and Paulitz, T. C. Soil acidification modifies soil depth-microbiome relationships in a no-till wheat.Soil Biology and Biochemistry: 149.
  • Yin, C. T., Vargas, J. M. C., Schlatter, D. C., Hagerty, C. H., Hulbert, S. H and Paulitz, T. C.Rhizosphere community selection reveals bacteria associated with reduced root disease. Microbiome 2021, 1186/s40168-020-00997-5
  • Yin, C. T., Schlatter, D. C., Kroese, D.R., Paulitz, T. C. and Hagerty, C. H. Responses of Soil Fungal Communities to Lime Application in Wheat Fields in the Pacific Northwest. 2021. Frontiers in Microbiology DOI 3389/fmicb.2021.576763
  • Schlatter, D. C., Hansen, J., Carolson, B., Leslie, In N. Huggins, D. R. and Paulitz, T. C.2021 Are microbial communities indicators of soil health in a dryland wheat cropping system?  Applied Soil Ecology 1016/j.apsoil.2021.104302.
  • Ahmadi, M., Mirakhorli, N., Erginbas-Orakci, G., Ansari, O., Braun, H. H., Paulitz, T., and Dababat, A. A. Interactions among cereal cyst nematode Heterodera filipjevi, dryland crown rot Fusarium culmorum, and drought on grain yield components and disease severity in bread wheat. 2022. Canadian Journal of Plant Pathology.
  • Laasli, S. E., Mokrini, F., Lahlali, R., Wuletaw, T., Paulitz, T. and Dababat, A. A. Biodiversity of Nematode Communities Associated with Wheat (Triticum aestivum) in Southern Morocco and Their Contribution as Soil Health Bioindicators. 2022. Diversity Basil 10.3390/d14030194