Ray Hammerschmidt, Ph.D.

Ray Hammerschmidt

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Professor & Faculty Coordinator of MSU Plant and Pest Diagnostics
Department of Plant, Soil and Microbial Sciences



B.S., Purdue University, Biochemistry
M.S. Purdue University, Plant Pathology
Ph.D., University of Kentucky, Plant Pathology

Overview of current program:

Plants are subjected to infection and attack by many different pathogens. However, the evolution of multiple defenses has allowed plants to effectively defend themselves against many of these attacks. Although many potential constitutive and induced defenses have been identified, the specific role and contribution of each to defense have been defined in only a few cases. Current research is involved in elucidating the nature and role of these defenses in several plant-pathogen systems using cytological, chemical, biochemical and molecular techniques. The major goals are to determine which mechanisms of defense are most important in the expression of resistance. Specific projects include the chemistry and role of phytoanticipins in periderm tissues of Prunus spp. as part of passive defense,  the biochemical nature of defense against potato tuber pathogens,  the role of natural and wound-induced periderm and suberin in potato tubers, and biochemical aspects of herbicide-disease interactions.

Courses taught:

  • PLP 405, Plant Pathology
  • PLP 881, Biochemical and Molecular Plant Pathology

Extension and outreach activities:

  • Director, North Central Diagnostic Network
  • Coordinator, Plant Diagnostic Services


  1. Hammerschmidt R. 2017. How glyphosate affects plant disease development: it’s more than enhanced susceptibility. Pest Management Science. DOI 10.1002/ps.4521
  2. Krasnow C, Hammerschmidt R, Hausbeck MK. 2017. Characteristics of resistance to Phytophthora root and crown rot in Cucurbita pepo. Plant Disease 101: 659-665.
  3. Hammerschmidt R. 2015. Some of the many molecules that induce resistance. Physiological and Molecular Plant Pathology 90 (2): iii.
  4. Hammerschmidt R. 2015. Plants inducing plants. Physiological and Molecular Plant Pathology. 90: iii.
  5. Hammerschmidt R. 2015. Being an adult plant sometimes has its advantages, Physiological and Molecular Plant Pathology 89: v-vi.
  6. Hammerschmidt R. 2014  Chlorogenic acid: A versatile defense compound. Physiological and Molecular Plant Pathology 88: iii-iv.
  7. Sikora  EJ,  Allen TW,  Wise, KA  et al. 2014. A Coordinated Effort to Manage Soybean Rust in North America: A Success Story in Soybean Disease Monitoring Plant Disease 98: 864-875.
  8. Stack JP,  Bostock RM,  Hammerschmidt R, Jones, JB,  Luke E. 2014. The National Plant Diagnostic Network: Partnering to Protect Plant Systems. Plant Disease 98: 708-715.
  9. Hammerschmidt R.  2014.  Definitions and Some History. In, Walters DR,  Newton AC, Lyon GD (eds.), Induced resistance for Plant Defense: A sustainable approach to crop protection, 2nd ed.   Wiley, Pp 1-10.
  10. Hammerschmidt, R. 2013. Glyphosate, glyphosate resistant crops and plant disease: Is there a connection?  Outlooks on Pest Management 24: 201-205.
  11. Duke SO, Lydon J,  Koskinen WC,  Moorman TB,  Chaney RL,  Hammerschmidt R. 2012. Glyphosate effects on plant mineral nutrition, crop rhizosphere microbiota, and plant disease in glyphosate-resistant crops. Journal of Agricultural and Food Chemistry 60:10375-10397.
  12. Giordano, PR,  Vargas Jr JM,  Nikola,  TA, and  Hammerschmidt R. 2012.  Timing and frequency effects of lightweight rolling on dollar spot disease in creeping bentgrass putting greens. Crop Science 52: 1371-1378.
  13. Vidigal, PS, Goncalves-Vidigal, MC, da Rocha, AB, Hammerschmidt, R.,  Kirk, WW, Poletine, JP and  Kelly, JD. 2011. Characterization and content of total soluble protein and amino acids of traditional common bean cultivars collected in Parana state, Brazil. Journal of Food, Agriculture and Environment. 9:143-147.
  14. Varbanova M,  Porter, K,  Lu, F.,  Ralph J,  Hammerschmidt R,  Jones AD,  and  Day B. 2011. Molecular and biochemical basis for stress-induced accumulation of free and bound p-coumaraldehyde in Cucumis sativus. Plant Physiology 157: 1056-1066.