Professor of Plant Pathology

Purdue University
Botany and Plant Pathology, Lilly Hall
915 West State Street
West Lafayette, IN 47907-2054

Office:  WSLR B018
FAX:      (765) 496-5896

Area: Disease Physiology - Phenolic compound biochemistry and metabolism of secondary palnt products in disease interactions; the fungal extracellular matrix, adhesion, control of differentiation in the fungal infection process.

Subcellular phytoalexin localization

Education

Ph.D., Purdue University , Plant Pathology

Nicholson is the author of over 120 articles, reviews, and book chapters. In addition to being a Fellow of APS, he has been a Fellow of the Japanese Society for the Promotion of Science and is a Guest Professor at the University of Konstanz, Germany.

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Research Interests

The ability of many plants to protect themselves from infection by pathogenic fungi depends on the synthesis of toxic secondary metabolites. One of the goals of our program is to understand the regulation of phenolic biosynthesis that occurs as a response to infection of the monocotyledonous plants corn and sorghum. With corn, we are investigating enzymes of phenylpropanoid biosynthesis with emphasis on 4-hydroxycinnamic acid CoA ligase. This enzyme regulates where in the cell phenylpropanoids will be diverted for continued phenolic synthesis. In sorghum, we are investigating the route of synthesis of phytoalexins, compounds that are 3-deoxyanthocyanidin flavonoids. These compounds are synthesized in subcellular inclusions that appear in response to attempted fungal infection.

Our work also involves understanding how fungi survive under adverse conditions. We are using the conidial mucilage of Colletotrichum graminicola as a model system. The mucilage acts as an antidesiccant and maintains spore viability during periods of dryness. It also contains several enzymes and proline-rich proteins that function as protectants against plant phenolics. This system is providing a tool for understanding the basis of survival as well as factors essential to virulence of the pathogen such as the process of adhesion.

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Teaching

I teach graduate courses in disease physiology and phenolic compound biochemistry. In disease physiology students learn physiological and biochemical aspects of the infection process and consider the temporal changes in host and pathogen physiology that occur during disease development. Phenolic biochemistry provides students with structure, synthesis, chemical properties, and importance of these compounds in plants.

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Assistantships and Positions

Please contact me directly for information on assistantships and openings in my program. Follow these links for general information on graduate programs or employment announcements.

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Selected Publications

Aguero, M.E, Gevens, A., and Nicholson, R.L. 2002. Interaction of Cochliobolus heterostrophus with phytoalexin inclusions in Sorghum bicolor. Physiological and Molecular Plant Pathology. 61:267-271.

Bergstrom, G.C, and Nicholson, R.L. 1999. The biology of Colletotrichum graminicola and maize anthracnose in "Host specificity, pathology and host pathogen interaction of Colletotrichum" D. Prusky, S. Freeman, and M. Dickman (eds.) APS Press, St. Paul.

Boddu J, Svabek C, Sekhon R, Gevens A, Nicholson RL, Jones AD, Pedersen JF, Gustine DL, Chopra S. 2005. Expression of a putative flavonoid 3’ hydroxylase in sorghum mesocotyls synthesizing 3-deoxyanbthocyanidins. Physiological and Molecular Plant Pathology. 65:101-113.

Carver, T.L.W., Kunoh, H. Thomas, B.J., and Nicholson, R.L. 1999. Release and Visualization of the Extracellular Matrix of Conidia of Blumeria graminis. Mycological Rearch. 103:547-560.

Epstein L, and Nicholson RL. 1997. Adhesion of spores and hyphae to plant surfaces. THE MYCOTA: Carroll G, Tudzynski P (eds.). Vol V, Part A, p. 11-25.

Gevens, A. and Nicholson, R.L. 2000. Cutin composition: A subtle role for fungal cutinase? Physiological and Molecular Plant Pathology. 57:43-45

Gevens, A., Carver T.L.W., Thomas, B.J., and Nicholson, R.L. 2001. Visualization and partial characterization of the extracellular matrix of Pestalotia malicola. Physiological and Molecular Plant Pathology. 58: 277-285.

Gevens, A.J., Carver, T.LW, Thomas, B.J., and Nicholson, R.L. 2001. Visualiation and partial characterization of the ECM of Pestalotia malicola on artificial and natural substrata. Physiol. and Molec. Plant Pathol. 58:277-285.

Hipskind, J., Wood, K., and Nicholson, R.L. 1996. Stimulation of anthocyanin accumulation and delineation of pathogen ingress in maize genetically resistant to Bipolaris maydis race O. Physiological and Molecular Plant Pathology. 49:247-256.

Hipskind, J.D., Goldsbrough, P.B., Urmeev, F., and Nicholson, R.L. 1996. Synthesis of 3-deoxyanthocyanidin phytoalexins in sorghum does not occur via the same pathway as 3-hydroxylated anthocyanidins and phlobaphenes. Maydica 41;155-166.

Hipskind, J.D., Nicholson, R.L., and Goldsbrough, P.B. 1996. Isolation of a cDNA encoding a novel leucine-rich repeat motif from Sorghum bicolor inoculated with fungi. Molecular Plant Microbe Interactions 9:819-825.

Kunoh, H., Yamaoka, N., Yoshioka, H., and Nicholson, R.L. 1988. Preparation of the infection court by Erysiphe graminis: I. Contact mediated changes in morphology of the conidium surface. Experimental Mycol. 12:325-335.

Lo, S.-C, de Verdier K, Nicholson, R.L. 1999. Accumulation of 3-deoxyanthocyanidin phytoalexins and resistance to Colletotrichum sublineolum. Physiological and Molecular Plant Pathology 55:263-273.

Lo, S-C, Weiergang, I., Bonham, C., Hipskind, J., Wood, K., and Nicholson, R.L. 1996. Phytoalexin accumulation in sorghum: Identification of a methyl ether of luteolinidin. Physiological and Molecular Plant Pathology 49:21-31.

Lo, Sze-Chung Clive, Hipskind, J. D., and Nicholson, R. L. 1999. cDNA cloning of a sorghum pathogenesis related protein (PR-10) and differential expression of defense-related genes following inoculation with heterostrophus or Colletotrichum sublineolum. Molecular Plant-Microbe Interactions 12: 479-489.

Meguro, A., Fujita, K, Kunoh, H., Carver, TLW, and Nicholson, RL. 2001. Release of the extracellular matrix from conidia of Blumeria graminis in relation to germination. Mycoscience 42:201-209.

Mercure, E.W., Kunoh, H., and Nicholson, R.L. 1995. Visualization of materials released from adhered, ungerminated conidia of Colletotrichum graminicola. Physiological and Molecular Plant Pathology. 46:121-135.

Mims, C.W., Richardson, E.A., Clay, R.P., and Nicholson, R.L. 1995. Ultrastructure of conidia and the condium aging process in the plant pathogenic fungus Colletotrichum graminicola. International J. Plant Sci. 156:9-18.

Nicholson, R.L., Hipskind, J., and Wood, K. 1995. Anthocyanins and deoxyanthocyanidins in plant defense: A mass spectrometric method for microanalysis. Polyphénol Actualités 12:20-21.

Nicholson, RL and Wood KV. 2001. Phytoalexins: What are they and how can we measure them? Physiological and Molecular Plant Pathology: 59:63-69

Nicholson, RL., and Kunoh, H. 1995. Early interactions, adhesion and establishment of the infection court by Erysiphe graminis. Canadian Journal of Botany. 73 (Suppl. 1): S609-615.

Nielsen KA, Gotfredsen CH, Buch-Pedersen MJ. Ammitzboll H, Mattsson O, Duus JO, Nicholson RL. 2004. Inclusions of flavonoid 3-deoxyanthocyanidins in Sorghum bicolor self-organize into spherical structures. Physiological and Molecular Plant Pathology. 65:187-196.

Nielsen, KA, Nicholson, RL., Carver TLW, Kunoh H, and Oliver, R.P. 2000. First touch: An immediate response to surface recognition in conidia of Blumeria graminis. Physiological and Molecular Plant Pathologhy. 56:63-70.

Oberthur, E.E., Nicholson, R.L., and Butler, L.G. 1983. Presence of polyphenolic materials, including condensed tannins, in sorghum callus. J. Agric. Food Chem. 31:660-662.

Orczyk, W., Hipskind, J, deNeergaard, E., Goldsbrough, P., and Nicholson, RL. 1996. Stimulation of phenylalanine ammonia-lyase in sorghum in response to inoculation with Bipolaris maydis. Physiological and Molecular Plant Pathology. 48:55-64.

Osswald, W.; Stangarlin, J.R.; Nicholson, R.L.; Brummer, M.; Wulff, N.A.; Di Piero, R.M.; Piccinin, E.; Di Ciero, L.; Hoto, F.V.; Pascholati, S.F. 2004. The effect of acibenzolar-S-methyl on phytoalexin and PR-production induction on sorghum mesocotyls and on Colletotrichum sublineolum. Summa Phytopathologica 30 (4): 415-420.

Shiraishi, T., Yamada, T., Nicholson, R.L., and Kunoh, H. 1995. Phenylalanine ammonia-lyase in barley: Activity enhancement in response to Erysiphe graminis f.sp. hordei (race 1) a pathogen, and pisi, a non-pathogen. Physiological and Molecular Plant Pathology 46:153-162.

Sugui, J.A. Bonham, C., Lo, S.C., Wood, K.V., and Nicholson, R.L. 1998. MALDI-TOF analysis of mixtures of 3-deoxyanthocyanidins and anthocyanins. Phytochemistry 48:1063-1066.

Sugui, J.A., Kunoh, H., and Nicholson, R.L. 1999. Detection of protein and carbohydrate in the extracellular matrix released by Cochliobolus heterostrophus during germination. Mycoscience. 40: 11-19

Sugui, J.A., Leite, B., and Nicholson, R.L. 1998. Partial characterization of the extracellular matrix released onto hydrophobic surfaces by conidia and conidial germlings of Colletotrichum graminicola. Physiological and Molecular Plant Pathology. 52:411-425.

Sugui, J.A., Pascholati, S.F., Kunoh, H, Howard, R., Nicholson, R.L. 1998. Cutinase and non-specific esterase produced by Pestalotia malicola. Physiological and Molecular Plant Pathology. 52:213-221.

Sugui, JA., Wood, KV., Yang, Z., Bonham, CC., and Nicholson, RL. 1999. Matrix-assisted laser desorption ionization mass spectrometry analysis of grape anthocyanins. American J. Enology and Viticulture. 50: 199-203

Vincent, J.R., and Nicholson, R.L. 1987. Evidence for isozymes of 4-hydroxycinnamic acid: CoA ligase in maize mesocotyls and their response to infection by Helminthosporium maydis race O. Physiol. Molec. Plant Pathol. 30:121-129.

Weiergang I, Wood KV, Dunkle LD, Nicholson RL. 2004. In vivo growth and pathotoxin production by the maize pathogen Cochliobolus carbonum. Physiological and Molecular Plant Pathology. 64:273-279.

Weiergang, I., Dunkle, L.D., Wood, K.V., and Nicholson, R.L. 1996. Morphogenic regulation of pathotoxin synthesis in Cochliobolus carbonum. Fungal Genetics and Biology 20:74-78.

Weiergang, I., Hipskind, J.D., and Nicholson, R.L. 1996. Synthesis of 3-deoxyanthocyanidin phytoalexins in sorghum occurs independent of light. Physiological and Molecular Plant Pathology. 49: 377-388..

Wharton, P.S. and Nicholson, R.L. 2000. Temporal synthesis and radiolabelling of the sorghum 3-deoxyanthocyanidin phytoalexins and the anthocyanidin 3-dimalonyl glucoside. New Phytologist 145:457-469.

Wright, A.J., Carver., T.L.W., Thomas., B.J., Femwick. N.I.D., Kunoh, H., and Nicholson, R.L., 2002. The rapid and accurate determination o f germ tube emergence site by Blumeria graminis conidia. Physiolgical and Molecular Plant Pathology. 57: --_---