Lindsey du Toit

Lindsey du Toit

Department Chair, Alfred Christianson Distinguished Professor of Vegetable Seed Pathology & Extension Plant Pathologist  360-848-6140 General Campus - Mt. Vernon 16650 State Route 536, Mount Vernon, WA 98273-4768

60% research: 30% extension: 10% teaching appointment

Research Specialty and Interests 

Epidemiology and management of diseases affecting vegetable seed crops (primarily small-seeded vegetables) in the Pacific Northwest. …more on Lindsey’s program 

For information on the Pacific Northwest Vegetable Extension Group, which Lindsey leads. 

Watch Washington State University and CAHNRS College Present: Focus on Research 


  • PhD, University of Illinois in Urbana-Champaign (plant pathology dissertation on common smut of sweet corn directed by Prof. Jerald Pataky) 
  • MS, University of Illinois in Urbana-Champaign (plant pathology thesis on Fusarium root rot of field corn directed by Dr. H.W. Kirby) 
  • BS, University of Natal-Pietermaritzburg, South Africa (plant pathology major) 

Professional Experience and Activities


Lindsey teaches Field Plant Pathology (Pl P 525), a 3-credit graduate course, in even summers (since 2012). The vegetable seed pathology program also provides funding and facilities for MS and PhD graduate research projects on vegetable diseases. 

  • Professional Activities 
  • Vice President (2017-2018), President-Elect (2018-2019), President (2019-2020), and Immediate Past President (2020-2021) of the American Phytopathological Society 
  • Councilor-at-Large for the American Phytopathological Society (2014-2017) 
  • Senior Editor for Plant Disease (2010-2012, 2013-2015) 
  • Associate Editor for Agronomy Journal (2008-2011) 
  • Associate Editor for Phytopathology (2010) 
  • Associate Editor for Plant Disease (2000-2002) 
  • Section Editor for Fungicide & Nematicide Tests/Plant Disease Management Reports (2005-2009) 
  • Ad-hoc reviewer for >12 peer-reviewed journals 
  • Service on several USDA NIFA grant review panels 

Awards, Honors, and Memberships 

  • 2022 Fellow of the American Phytopathological Society 
  • 2019 ‘Friend of the Industry’ Award from the Pacific Northwest Vegetable Association in recognition of outstanding service to the vegetable industry in the Pacific Northwest USA 
  • Alfred Christianson Distinguished Professor in Vegetable Seed Science (since 2018) 
  • American Phytopathological Society Presidential Team (Vice President, 2017-18; President-Elect, 2018-19; President, 2019-20; Immediate Past President, 2020-21) 
  • American Phytopathological Society Councilor-at-Large (2014-2017) 
  • American Phytopathological Society Syngenta Award for outstanding recent contributions to research/extension in plant pathology (2013) 
  • WSU CAHNRS Interdisciplinary Team Excellence Award for the Pacific Northwest Vegetable Extension Group (PNW VEG) (2012) 
  • WSU Kenneth J. Morrison Extension Award for outstanding contributions to improvement of Washington State crop production (2009) 
  • Alfred Christianson Family Endowed Professorship (2001-05, 2006-10, 2012-17) 
  • Robert MacDonald Vegetable Seed Memorial Fund (2003-06, 2008-11, 2013, 2017-20) 
  • 2006 Early Career Award of the Pacific Division of the American Phytopathological Society 
  • Member: American Phytopathological Society (chair of Seed Pathology Committee, 2007-09 & 2022-23; chair of Diagnostics Committee, 2002-03); International Society of Plant Pathology; Southern African Society of Plant Pathologists 


Journals (since 2012)

  • Batson, A.M., Gyawali, S., and du Toit, L.J. 2022. Shedding light on races of the spinach Fusarium wilt pathogen, Fusarium oxysporum f. sp. spinaciae. Phytopathology 112: First Look.  
  • Batson, A., Spawton, K, Katz, R., and du Toit, L.J. 2022. Cladosporium leaf spot, caused by Cladosporium variabile, in winter high tunnel production of spinach (Spinacia oleracea) in Maine, United States. Plant Disease 112: in press. PDIS-11-21-2424-PDN.R1. 
  • Belo, T., LaHue, G., and du Toit, L.J. 2022. Reducing the risk of onion bacterial diseases through irrigation, fertility, and other cultural management strategies. Agronomy Journal: accepted. AJ-2021-11-1053-R.R1. 
  • Shi, A., Bhattarai, G., Xiong, H., Avila, C.A., Feng, C., Liu, B., Joshi, V., Stein, L., Mou, B., du Toit, L.J., and Correll, J.C. 2022. Genome-wide association study and genomic prediction of white rust resistance in USDA GRIN spinach germplasm. Horticulture Research: 
  • Batson, A.M., Fokkens, L., Rep, M., and du Toit, L.J. 2021. Putative effector genes distinguish two pathogenicity groups of Fusarium oxysporum f. sp. spinaciae. Molecular Plant-Microbe Interactions 34:141-156. 
  • Block, A.K., Tang, H.V., Hopkins, D., Mendoza, J., Solemslie, R.K., du Toit, L.J., and Christensen, S.A. 2021. A maize leucine-rich repeat receptor-like protein kinase mediates responses to fungal attack. Planta 254:73. 
  • Gyawali, S., Bhattarai, G., Shi, A., Kik, C., and du Toit, L.J. 2021. Genetic diversity, structure, and selective sweeps in Spinacia turkestanica associated with the domestication of cultivated spinach. Frontiers in Genetics 12:740437. 
  • Gyawali, S., Derie, M.L., Gatch, E.W., Sharma-Poudyal, D., and du Toit, L.J. 2021. Lessons from 10 years of stakeholder adoption of a soil bioassay for spinach Fusarium wilt. Plant Pathology 70:778-792. 
  • Hulse-Kemp, A.M., Bostan, H., Chen, S., Ashrafi, H., Stoffel, K., Sanseverino, W., Li, L., Cheng, S., Schatz, M.C., Garvin, T., du Toit, L.J., Tseng, E., Chin, J., Iorizzo, M., and van Deynze, A. 2021. An anchored chromosome-scale genome assembly of spinach (Spinacia oleracea) improves annotation and reveals extensive gene rearrangements in euasterids. Plant Genome 14:e20101. 
  • Liu, B., Stein, L., Cochran, K., du Toit, L.J., and Correll, J.C. 2021. Three new fungal leaf spot diseases of spinach and the evaluation of fungicide efficacy for disease management. Plant Disease 105:316-323. 
  • McDonald, M.R., Collins, B., du Toit, L.J., and Adusei-Fosu, K. 2021. Soil amendments for the management of Fusarium wilt of bunching spinach in Ontario, Canada. Crop Protection 145:105646.  
  • Nampijja, M., Derie, M.L., and du Toit, L.J. 2021. First report of bacterial leaf spot caused by Pseudomonas syringae pv. atata on Swiss chard, Beta vulgaris subsp. vulgaris, in Arizona. Plant Disease 105:3738. 
  • Swisher Grimm, K.D., Crosslin, J.M., Cooper, W.R., Frost, K.E., du Toit, L.J., and Wohleb, C.H. 2021. First report of curly top of Coriandrum sativum caused by Beet curly top virus in the Columbia Basin of Washington State. Plant Disease 105:3313. 
  • Carmody, S.M., King, K.M., Ocamb, C.M., Fraaije, B.A., West, J.S., and du Toit, L.J. 2020. A phylogenetically distinct lineage of Pyrenopeziza brassicae associated with chlorotic leaf spot of Brassicaceae in North America. Plant Pathology 69:518-537. 
  • Liu, B., Stein, L., Cochran, K., du Toit, L.J., Feng, C., Dhillon, B., and Correll, J.C. 2020. Characterization of spinach leaf spot pathogens from several spinach production areas in the U.S. Plant Dis. 104:1994-2004. 
  • Synoground, T., Batson, A., Derie, M., Koenick, L.B., Pethybridge, S.J., and du Toit, L.J. 2020. First report of Cercospora leaf spot caused by Cercospora chenopodii on Spinacia oleracea in the USA. Plant Disease 104:976. 
  • Knerr, A.J., Wheeler, D., Schlatter, D., Sharma-Poudyal, D., du Toit, L.J., and Paulitz, T.C. 2019. Arbuscular mycorrhizal fungal communities in organic and conventional onion crops in the Columbia Basin of the Pacific Northwest USA. Phytobiomes 2:194-207. 
  • Koenick, L.B., Knight, N.L., Vaghefi, N., du Toit, L.J., and Pethybridge, S.J. 2019. Genetic diversity and differentiation in Phoma betae populations on table beet in New York and Washington States. Plant Disease 103:1487-1497. 
  • Zou, Z., Zhang, X., Parks, P., Van de Wouw, A. P., du Toit, L.J., and Dilantha Fernando, W.G. 2019. A new subclade of Leptosphaeria biglobosa identified from Brassica rapa. International Journal of Molecular Sciences 20:1668 doi:10.3390/ijms20071668.  
  • Fukada, H., Derie, M.L., Shishido, M, and du Toit, L.J. 2018. Phomopsis black root rot of cucumber in Washington State caused by Diaporthe sclerotioides. Plant Disease 102:1657. 
  • Gatch, E.W., and du Toit, L.J. 2017. Limestone-mediated suppression of Fusarium wilt in spinach seed crops. Plant Disease 101:81-94. 
  • Econopouly, B.F., Derie, M.L., Jones, S.S., and du Toit, L.J. 2017. Downy mildew of buckwheat, Fagopyrum esculentum, in the USA caused by Peronospora cf. documetii. Plant Disease 101:391.  
  • Moloto, V.M., Goszczynska, T., du Toit, L.J., and Coutinho, T.A. 2017. A new pathovar of Pseudomonas syringae, pathovar allii, isolated from onion plants exhibiting symptoms of blight. European Journal of Plant Pathology 146:591-603. 
  • Paulitz, T.C., Knerr, A.J., Carmody, S.M., Schlatter, D., Sowers, K., Derie, M.L., and du Toit, L.J. 2017. First report of Leptosphaeria maculans and Leptosphaeria biglobosa, causal agents of blackleg, on canola in Washington State. Plant Disease 101:504.  
  • Alcala, A.C., Paulitz, T.C., Schroeder, K.L., Porter, L.D., Derie, M.L., and du Toit, L.J. 2016. Pythium species associated with damping-off of pea in certified organic fields in the Columbia Basin of central Washington. Plant Disease 100:916-925. 
  • Sharma-Poudyal, D., Paulitz, T.C., and du Toit, L.J. 2016. Timing of glyphosate applications to wheat cover crops to reduce onion stunting caused by Rhizoctonia solani. Plant Disease 100:1474-1481. Monthly ‘Editor’s Pick’. 
  • Bull, C.T., Ortiz-Lytle, M.C., Ibarra, A.G., du Toit, L.J., and Reynolds, G. 2015. First report of bacterial blight of crucifers caused by Pseudomonas cannabina pv. alisalensis in Minnesota on arugula (Eruca vesicaria subsp. sativa). Plant Disease 99:415. 
  • Christianson, C.E., Jones, S.S., and du Toit, L.J. 2015. Screening carrot germplasm for resistance to Xanthomonas hortorum pv. carotae. HortScience 50:341-350. 
  • Gatch, E.W., and du Toit, L.J. 2015. A soil bioassay for predicting the risk of spinach Fusarium wilt. Plant Disease 99:512-526. 
  • Sharma-Poudyal, D., Paulitz, T.C., and du Toit, L.J. 2015. Evaluation of onion genotypes for resistance to stunting caused by Rhizoctonia solani AG 8. HortScience 50:551-554. 
  • Sharma-Poudyal, D., Paulitz, T.C., and du Toit, L.J. 2015. Stunted patches in onion bulb crops in Oregon and Washington: Etiology and yield loss. Plant Disease 99:648-658. 
  • Sharma-Poudyal, D., Paulitz, T.C., Porter, L.D., and du Toit, L.J. 2015. Characterization and pathogenicity of Rhizoctonia and Rhizoctonia-like species from pea crops in the Columbia Basin of Oregon and Washington. Plant Disease 99:604-613. 
  • du Toit, L.J., and Derie, M.L. 2014. White rust of Echinacea angustifolia and E. purpurea in North America caused by a Pustula species. Plant Disease 98:856. 
  • du Toit, L.J., Derie, M.L., and Alcala, A.C. 2014. First report of Pythium sulcatum causing cavity spot in processing carrot crops in the Columbia Basin of Washington State. Plant Disease 98:427. 
  • du Toit, L.J., Derie, M.L., Christianson, C.E., Hoagland, L., and Simon, P. 2014. First report of bacterial blight of carrot in Indiana caused by Xanthomonas hortorum pv. carotae. Plant Disease 98:685. 
  • Feng, C., Mansouri, S., Bluhm, B. H., du Toit, L.J., and Correll, J.C. 2014. Multiplex real-time PCR assays for detection of spinach seedborne pathogens. Journal of Applied Microbiology: in press. 
  • Iglesias-Garcia, A.M., Villarroel-Zeballos, M.I., Feng, C., du Toit, L.J., and Correll, J.C. 2013. Pathogenicity, virulence, and vegetative compatibility grouping of Verticillium isolates from spinach seed. Plant Disease 97:1457-1469. 
  • Okubara, P., Harrison, L.A., Gatch, E.W., Schroeder, K., Vandemark, G., and du Toit, L.J. 2013. Development and evaluation of a TaqMan real-time PCR assay for Fusarium oxysporum f. sp. spinaciae. Plant Disease 97:927-937. 
  • Patzek, L.J., du Toit, L.J., Paulitz, T.C., and Jones, S.S. 2013. Stunting of onion caused by Rhizoctonia spp. isolated from the Columbia Basin of Washington and Oregon. Plant Disease 97:1626-1635. 
  • Temple, T., du Toit, L.J., Derie, M.L., and Johnson, K. 2013. Quantitative molecular detection of Xanthomonas hortorum pv. carotae in carrot seed before and after hot water treatment. Plant Disease 97:1585-1592. 
  • du Toit, L.J., and Derie, M.L. 2012. First report of Cladosporium leaf spot of spinach caused by Cladosporium variabile in the winter spinach production region of California and Arizona. Plant Disease 96:1071. 
  • Rodriguez-Salamanca, L.M., Enzenbacher, T.B., Derie, M.L., du Toit, L.J., Feng, C., Correll, J.C., and Hausbeck, M.K. 2012. First report of Colletotrichum coccodes causing leaf and neck anthracnose on onions (Allium cepa) in Michigan and the United States. Plant Disease 96:769. 
  • Schroeder, B.K., Humann, J.L., and du Toit, L.J. 2012. Effects of postharvest onion curing parameters on the development of sour skin and slippery skin in storage. Plant Disease 96:1548-1555. 
  • Villarroel-Zeballos, M.I., Feng, C., Iglesias, A., du Toit, L.J., and Correll, J.C. 2012. Characterization of Verticillium dahliae from spinach seed, and screening for resistance to Verticillium wilt in spinach. HortScience 47:1297–1303. 
  • Wohleb, C.H., Waters, T.D, du Toit, L.J., and Schroeder, B.K. 2012. The Washington State University Onion Cultivar Trial: An important resource for Washington onion growers. Acta Horticulturae 969:241-246.