Gretchen A. Kuldau, Ph.D.

Gretchen A. Kuldau, Ph.D.

  • Associate Professor
308 Buckhout Lab (office)
417 Buckhout Lab (lab)

University Park, PA 16802

Areas of Expertise

  • Mycotoxins
  • Endophytes
  • Fusarium
  • Fungal genetics
  • Fungal secondary metabolites
  • Agricultural biosecurity



  • B.A., Biology, Wellesley College
  • Ph.D., Molecular and Physiological Plant Biology, University of California Berkeley

Areas of Interest

Role of mycotoxins in fungal biology, genetics and molecular biology, prevention of mycotoxin accumulation in feeds and forages; genetics and biology of endophytic fungi

Program Interests

Research in my lab focuses on mycotoxigenic fungi and their interactions with plants. Mycotoxins are fungal secondary metabolites that are toxic to humans and animals. These naturally occurring toxins are of concern for both human and animal health since some are human carcinogens and others can cause fatal diseases in farm animals. In most cases, the biological motivation for mycotoxin production is unknown. While we have a relatively clear understanding of the nature of many of the commonly found mycotoxins we often do not know why they are made. One of the primary goals of my program is to understand why fungi produce mycotoxins. Such knowledge should provide the basis for new strategies for prevention of accumulation of mycotoxins in food and feed.

We work primarily with Fusarium verticillioides and interactions with maize and Fusarium graminearum as the causal agent of head scab of wheat. A number of mycotoxigenic fungi exist as endophytes during some or all of their lives including F. verticillioides. Endophytes are microorganisms that live internal to plant tissues but cause no observable symptoms on their plant host. Some endophytic fungi can be pathogenic under certain environmental and or developmental conditions. Very little is known for any fungus about the genetic basis for asymptomatic colonization of plants or about why symptomless infections sometimes become symptomatic. We are working to identify genes specifically expressed during endophytic colonization of maize by F. verticilloides. Our approach to this problem employs the tools of fungal molecular genetics.


Li, G. Wenner, N., and Kuldau, G. A. 2015. FvSO regulates vegetative hyphal fusion, asexual growth, fumonisin B1 production and virulence in Fusarium verticillioides. 2015. Fungal Biology, 119: 1158-1169, doi:10.1016/j.funbio.2015.08.13.

 Li, G., Blatt, A. Z., Geiser, D. M., Jimenez-Gasco, MM, and Kuldau, G. A. 2015. Mating type and spore killing characterization of Fusarium verticillioides strains.  Mycological Progress 14:16.

Rahman, A., Kuldau, G. A., and Uddin, W. 2014. Induction of salicyclic acid-mediated defense response in perennial ryegrass against infection by Magnaporthe oryzae. Phytopathology, 104: 614-623.

Kuldau, G. A. 2014. Masters-level agricultural biosecurity education for location-bound adult learners. Plant Health Instructor, in press.

Malcolm, G. M., Kuldau, G. A., Gugino, B. K., and Jimenez-Gasco, M. M. 2013. Letter to the Editor: Hidden host plant associations of soilborne fungal pathogens: An ecological perspective. Phytopathology 103: 538-544.

Geiser, D. M. ……Kuldau, G. A., and 65 others. 2013. Letter to the Editor: Defining the genus Fusarium in a scientifically robust way that preserves longstanding use. Phytopathology 103: 400-408.

Hallen-Adams, H., Wenner, N., Kuldau, G. and Trail, F. 2011. Deoxynivalenol gene expression during wheat kernel colonization by Fusarium graminearumPhytopathology 101: 1091-1096.

Baines, D., Erb, S., Lowe, R., Turkington, K., Sabau, E., Kuldau, G., Juba, J., and Roberts, R. A. 2011. Mouldy feed, mycotoxins and Shiga-toxin-producing Escherichia coli colonization in associated with Jejunal Hemorrhage Syndrome in beef cattle. BMC Veterinary Research, 7:24.

Kuldau, G. and Bacon, C. 2008. Clavicipitaceous endophytes: Their ability to enhance grass resistance to multiple stresses. Biological Control 46: 57-71.

Mansfield, M. A., Jones, A. D. and Kuldau, G. A. 2008. Contamination of fresh and ensiled maize with four mycotoxins produced by Penicillium species. Phytopathology 98: 330-336.

Mansfield, M. A. and Kuldau, G. A. 2007. Microbiological and molecular determination of mycobiota in fresh and ensiled maize. Mycologia 99:269-278.

Mansfield, M. A., Archibald, D. D., Jones, A. D. and Kuldau, G. A. 2007. Relationship of sphinganine analog mycotoxin contamination in maize silage to seasonal weather conditions, and agronomic and ensiling practices. Phytopathology 97:504-511.

Sekhon, R., Kuldau, G., Mansfield, M., Jones, A. D., and Chopra, S. 2006. Characterization of Fusarium-induced expression of flavonoids and PR genes in maize. Physiological and Molecular Plant Pathology, 69:109-117.

Kuldau, G. A., and M. A. Mansfield. 2006. Mycotoxins and mycotoxigenic fungi in silages. Silage for Dairy Farms Conference, pp. 91-99, January 23-25, 2006, Camp Hill, PA, Natural Resource, Agriculture and Engineering Service, Ithaca, NY.

Mansfield, M. A., De Wolf, E. D., and Kuldau, G. A. 2005. Effect of weather conditions, cultural practices, and feed quality on deoxynivalenol content in maize silage. Plant Disease, 89:1151-1157.

Nita, M., Tilley, K., DeWolf, E., and Kuldau, G. 2005. Effects of moisture during and after anthesis on the development of Fusarium Head Blight of wheat and mycotoxin production. In: Canty, S. M., Lewis, J., Siler, L., and Ward, R. W. (Eds.), Proceedings of the National Fusarium Head Blight Forum; 2005 Dec. 11-13, Milwaukee, MN. East Lansing: Michigan State University. pp. 125-128.

Bacon, C. W., Hinton, D. M., Porter, J. K., Glenn, A. E. and Kuldau G. A. 2004. Fusaric acid, Fusarium verticillioides metabolite, antagonistic to the endophyte biocontrol bacterium Bacillus mojavensis. Canadian Journal of Botany 82:878-885.

Dillehay, B. J., Roth, G. W., Calvin, D. D., Kratochvil, R. J., Kuldau, G. A., and Hyde, J. A. 2004. Performance of Bt-corn hybrids, their near isolines and leading corn hybrids in Pennsylvania and Maryland. Agronomy Journal 96:818-824.

Geiser, D. M., del Mar Jimenez-Gasco, M., Kang, S., Makalowska, I., Veeraraghaven, N., Ward, T. J., Zhang, N., Kuldau, G. A., and O'Donnell, K. 2004. FUSARIUM-ID v.1.0: A DNA sequence database for identifying Fusarium. European Journal of Plant Pathology 110:473-479.

Kuldau, G. A., and I. E. Yates. 2000. "Evidence for Fusarium endophytes in cultivated and wild plants." In: Biology and evolution of microbial endophytes. C. W. Bacon and J. F. White Jr., eds. pp. 85-117.

Kuldau, G. A., and C. W. Bacon. 2000. "Biology and toxicity of Clavicipitaceae ." In: Foodborne disease Handbook, vol. 3. Y. H. Hui, R. A. Smith, and D. G. Spoerke eds. Marcel Dekker, Inc., New York, pp. 503-534.

Kuldau, G. A., H.-F. Tsai, C. L. Schardl. 1999. "Genome sizes of Epichloe species and anamorphic hybrids." Mycologia 91: 776-782.


The sting of sizeism at work
Nature, Kuldau, Gretchen, 2022

Fusarium Head Blight of Small Grains in Pennsylvania: Unravelling Species Diversity, Toxin Types, Growth, and Triazole Sensitivity
Phytopathology, Duffeck, Maíra R., Bandara, Ananda Y., Weerasooriya, Dilooshi K., Collins, Alyssa A., Jensen, Philip J., Kuldau, Gretchen A., Del Ponte, Emerson M., Esker, Paul D., 2022

Cover crop selection affects maize susceptibility to the fungal pathogen Fusarium verticillioides
Pedobiologia, Ray, Swayamjit, Wenner, Nancy G., Ankoma_Darko, Obenewa, Ankoma-Darko, Obenewa, Kaye, Jason P., Kuldau, Gretchen A., Ali, Jared G., 2022

Fusarium head blight of small grains in Pennsylvania: unravelling species diversity, toxin types, growth and triazole sensitivity
Phytopathology, Duffeck, Maira, Bandara, Ananda, Weerasooriya, Dilooshi, Collins, Alyssa, 2021

Phylogenomic analysis of a 55.1-kb 19-gene dataset resolves a monophyletic fusarium that includes the fusarium solani species complex
Phytopathology, Geiser, David M., Al-Hatmi, Abdullah M.S., Aoki, Takayuki, Arie, Tsutomu, Balmas, Virgilio, Barnes, Irene, Bergstrom, Gary C., Bhattacharyya, Madan K., Blomquist, Cheryl L., Bowden, Robert L., Brankovics, Balazs, Brown, Daren W., Burgess, Lester W., Bushley, Kathryn, Busman, Mark, Cano-Lira, Jose F., Carrillo, Joseph D., Chang, Hao Xun, Chen, Chi Yu, Chen, Wanquan, Chilvers, Martin, Chulze, Sofia, Coleman, Jeffrey J., Cuomo, Christina A., Wilhelm de Beer, Z., Sybren de Hoog, G., Castillo-Munera, Johanna Del, Del Ponte, Emerson M., Dieguez-Uribeondo, Javier, Pietro, Antonio Di, Edel-Hermann, Veronique, Elmer, Wade H., Epstein, Lynn, Eskalen, Akif, Esposto, Maria Carmela, Everts, Kathryne L., Fernandez-Pavıa, Sylvia P., da Silva, Gilvan Ferreira, Foroud, Nora A., Fourie, Gerda, Frandsen, Rasmus J.N., Freeman, Stanley, Freitag, Michael, Frenkel, Omer, Fuller, Kevin K., Gagkaeva, Tatiana, Gardiner, Donald M., Glenn, Anthony E., Gold, Scott E., Gordon, Thomas R., Gregory, Nancy F., Gryzenhout, Marieka, Guarro, Josep, Gugino, Beth K., Gutierrez, Santiago, Hammond-Kosack, Kim E., Harris, Linda J., Homa, Monika, Hong, Cheng Fang, Hornok, Laszlo, Huang, Jenn Wen, Ilkit, Macit, Jacobs, Adriaana, Jacobs, Karin, Jiang, Cong, del Mar Jimenez-Gasco, Marıa, Kang, Seogchan, Kasson, Matthew T., Kazan, Kemal, Kennell, John C., Kim, Hye Seon, Corby Kistler, H., Kuldau, Gretchen A., Kulik, Tomasz, Kurzai, Oliver, Laraba, Imane, Laurence, Matthew H., Lee, Theresa, Lee, Yin Won, Lee, Yong Hwan, Leslie, John F., Liew, Edward C.Y., Lofton, Lily W., Logrieco, Antonio F., Lopez-Berges, Manuel S., Luque, Alicia G., Lysøe, Erik, Ma, Li Jun, Marra, Robert E., Martin, Frank N., May, Sara R., McCormick, Susan P., McGee, Chyanna, Meis, Jacques F., Migheli, Quirico, Mohamed Nor, N. M.I., Monod, Michel, Moretti, Antonio, Mostert, Diane, Mule, Giuseppina, Munaut, Françoise, Munkvold, Gary P., Nicholson, Paul, Nucci, Marcio, O’Donnell, Kerry, Pasquali, Matias, Pfenning, Ludwig H., Prigitano, Anna, Proctor, Robert H., Ranque, Stephane, Rehner, Stephen A., Rep, Martijn, Rodrıguez-Alvarado, Gerardo, Rose, Lindy Joy, Roth, Mitchell G., Ruiz-Roldan, Carmen, Saleh, Amgad A., Salleh, Baharuddin, Sang, Hyunkyu, Scandiani, Marıa Mercedes, Scauflaire, Jonathan, Schmale, David G., Short, Dylan P.G., Sisic, Adnan, Smith, Jason A., Smyth, Christopher W., Son, Hokyoung, Spahr, Ellie, Stajich, Jason E., Steenkamp, Emma, Steinberg, Christian, Subramaniam, Rajagopal, Suga, Haruhisa, Summerell, Brett A., Susca, Antonella, Swett, Cassandra L., Toomajian, Christopher, Torres-Cruz, Terry J., Tortorano, Anna M., Urban, Martin, Vaillancourt, Lisa J., Vallad, Gary E., van der Lee, Theo A.J., Vanderpool, Dan, van Diepeningen, Anne D., Vaughan, Martha M., Venter, Eduard, Vermeulen, Marcele, Verweij, Paul E., Viljoen, Altus, Waalwijk, Cees, Wallace, Emma C., Walther, Grit, Wang, Jie, Ward, Todd J., Wickes, Brian L., Wiederhold, Nathan P., Wingfield, Michael J., Wood, Ana K.M., Xu, Jin Rong, Yang, Xiao Bing, Yli-Mattila, Tapani, Yun, Sung Hwan, Zakaria, Latiffah, Zhang, Hao, Zhang, Ning, Zhang, Sean X., Zhang, Xue, 2021

Population Genetic Structure and Chemotype Diversity of Fusarium graminearum Populations from Wheat in Canada and North Eastern United States
Toxins, Oghenekaro, Abbot O., Oviedo-Ludena, Maria A., Serajazari, Mitra, Wang, Xiben, Henriquez, Maria A., Wenner, Nancy G., Kuldau, Gretchen A., Navabi, Alireza, Kutcher, Hadley R., Fernando, W. G.Dilantha, 2021

Proposal for a Center for Integrated Agricultural Diagnostics at Penn State, Call, Christina, Geiser, DAvid, Kuldau, Gretchen, Jimenez-Gasco, Maria del Mar, May, Sara, Yang, Yinong, 2021

Root cortical anatomy is associated with differential pathogenic and symbiotic fungal colonization in maize
Plant, Cell and Environment, Galindo-Castañeda, Tania, Galindo-Castenada, Tania, Galindo-Castaneda, Tania, Brown, Kathleen, Kuldau, Gretchen, Roth, Gregory, Wenner, Nancy G., Ray, Swayamjit, Swayamnit, Ray, Schneider, Hannah, Lynch, Jonathan P., 2019

Manipulating Wild and Tamed Phytobiomes: Challenges and Opportunities
Phytobiomes Journal, Collins, Alyssa, Bell, Terrence H, Hockett, Kevin, Esker, P, Alcala-Briseno, Ricardo, Gugino, B, Alcalá-Briseño, Ricardo, Barbercheck, Mary, Peter, K, Beattie, Gwyn, Bruns, Mary Ann, Carlson, John, Chung, Taejung, Collins, A, Emmett, Bryan, Esker, Paul, Garrett, Karen, Glenna, Leland, Gugino, Beth K., Del Mar Jiménez-Gasco, María, del Mar Jimenez Gasco, M, Jimenez Gasco, Maria del Mar, Kinkel, Linda, Kovac, Jasna, Kowalski, Kurt, Kowalski, Kurt, Leveau, Johan, Myrick, J, Kuldau, Gretchen, Peter, K, Leveau, Johan, Michalska-Smith, Matthew, Salazar, Maria, Myrick, Jessica, Shade, Ashley, Peter, Kari, Stopnisek, Nejc, Tan, Xiaoqing, Vivanco Salazar, Maria fernanda, Salazar, Maria, Shade, Ashley, Welty, Amy, Stopinsek, Nejc, Stopnisek, Nejc, Wickings, Kyle, Yergeau, Etienne, Tan, Xiaoqing, Welty, Amy, Wickings, Kyle, Wickings, Etienne, Yergeau, Etienne, 2019

MASMC 2016 at Penn State
Inoculum, Kuldau, Gretchen, 2016

Mating type and spore killing characterization of Fusarium verticillioides strains
Mycological Progress, Guo, Li, Blatt, Adam Z., Geiser, David M., Jiménez-Gasco, Maria del Mar, Kuldau, Gretchen A., 2015

Methods of instruction of the incident command system and related topics at US veterinary schools
Disaster Medicine and Public Health Preparedness, Smith, Joe S., Kuldau, Gretchen A., 2014

Hidden host plant associations of soilborne fungal pathogens: An ecological perspective
Phytopathology, Malcolm, Glenna M., Kuldau, Gretchen A., Gugino, Beth K., Jiménez-Gasco, María Del Mar, 2013

One fungus, one name: Defining the genus Fusarium in a scientifically robust way that preserves longstanding use
Phytopathology, Geiser, David M., Aoki, Takayuki, Bacon, Charles W., Baker, Scott E., Bhattacharyya, Madan K., Brandt, Mary E., Brown, Daren W., Burgess, Lester W., Chulze, Sofia, Coleman, Jeffrey J., Correll, James C., Covert, Sarah F., Crous, Pedro W., Cuomo, Christina A., De Hoog, G. Sybren, Di Pietro, Antonio, Elmer, Wade H., Epstein, Lynn, Frandsen, Rasmus J.N., Freeman, Stanley, Gagkaeva, Tatiana, Glenn, Anthony E., Gordon, Thomas R., Gregory, Nancy F., Hammond-Kosack, Kim E., Hanson, Linda E., Del Mar Jímenez-Gasco, María, Kang, Seogchan, Corby Kistler, H., Kuldau, Gretchen A., Leslie, John F., Logrieco, Antonio, Lu, Guozhong, Lysøe, Erik, Ma, Li Jun, McCormick, Susan P., Migheli, Quirico, Moretti, Antonio, Munaut, Françoise, O'Donnell, Kerry, Pfenning, Ludwig, Ploetz, Randy C., Proctor, Robert H., Rehner, Stephen A., Robert, Vincent A.R.G., Rooney, Alejandro P., Bin Salleh, Baharuddin, Scandiani, Maria Mercedes, Scauflaire, Jonathan, Short, Dylan P.G., Steenkamp, Emma, Suga, Haruhisa, Summerell, Brett A., Sutton, Deanna A., Thrane, Ulf, Trail, Francis, Van Diepeningen, Anne, VanEtten, Hans D., Viljoen, Altus, Waalwijk, Cees, Ward, Todd J., Wingfield, Michael J., Xu, Jin Rong, Yang, Xiao Bing, Yli-Mattila, Tapani, Zhang, Ning, 2013