photo: Rebecca SweanyRebecca Sweany

Graduate Student
Major Professor: Dr. Kenneth Damann


  • 2013-present:  Doctor of Philosophy student, Louisiana State University Plant Health (Major Plant Pathology; minor Crop Physiology)
  • 2012-2010:  Research Associate, LSU AgCenter, Department of Plant Pathology and Crop Physiology. Studied sweetpotato disease control under the direction of Drs. Chris Clark, Dave Picha and Don Labonte.
  • 2010-2007:  Master of Science, Louisiana State University, Department of Plant Pathology and Crop Physiology (2010). Earned a Master of Science in Plant Health. Thesis entitled: A Comparison of Soil and Corn Kernel Aspergillus flavusPopulations: Evidence for Niche Specialization
  • 2007-2003: Research Associate, LSU AgCenter, Department of Plant Pathology and Crop Physiology. Studied biocontrol of aflatoxin in corn.
  • 2003-1998:  Bachelor of Science, Louisiana State University (2003). Earned a Bachelor of Science in Wildlife and Fisheries with a concentration in Conservation and minors in Chemistry and Biological Sciences. Graduated Magna cum Laude.
  • Student worker for Drs. Bill Kelso and Alan Rutherford from Jan. 2002-May ‘03.
  • Student worker for Dr. Meredith Blackwell from Sept. 2000- Dec. 2001.
  • LSU Swahili Safari 2001 in Bagamoyo, Tanzania, Africa. Studied Swahili and Contemporary Africa as part of a summer study-abroad program

Current Research:

My research interests cover several avenues related to understanding the biology ofAspergillus flavus and aflatoxin regulation.  Aflatoxin is an acute toxin and a carcinogen produces primarily by the fungus A. flavus.  Aflatoxin contamination of corn, cotton and peanuts is a perennial concern to producers in Louisiana, Southern United States and tropical-subtropical climates.    As little as 20 parts per billion of aflatoxin contamination can result in rejection at the elevators and prevent interstate shipment.

My primary focus is understanding the mechanism of biocontrol.  Currently the best control of aflatoxin contamination is cultural methods that reduce water stress and application of a biocontrol non-toxigenic A. flavus strain.  The conventional wisdom states the mode of biocontrol works through competitive exclusion.  Meaning that the environment is flooded with the atoxigenic strain which then has a higher probability to infect before toxigenic indigenous strains and subsequently blocks infection of the toxigenic strains.  Our lab demonstrated an addition mode of action of the biocontrol strains.  We showed, when there is a physical interaction between the toxigenic strains and biocontrol, the toxigenic strain produces significantly less aflatoxin (almost none).   The primary focus of my research will be to determine how this physical interaction leads to less aflatoxin production.

The second portion of my dissertation will investigate the specificity of certain strains to infect corn.  There is evidence from multiple studies that there is niche specialization for different strains to either live in soil or in crops.  My master’s research discovered two different populations of A. flavus residing on the soil and in corn.  It is unclear whether these differences are attributable to differences in pathogenicity or survivability in the soil.  I intend to determine if there are differences in pathogenicity between the soil and corn populations by comparing the ability of abundant strains from the corn and soil to naturally infect corn.

The final portion will investigate volatile chemical impacts on aflatoxin production. 

Refereed Publications:

  • Huang, C., Jha A., Sweany, R., DeRobertis, C., Damann, KE Jr. 2011.  Intraspecific Aflatoxin Inhibition in Aspergillus flavus Is Thigmoregulated, Independent of Vegetative Compatibility Group and Is Strain Dependent. PLoS ONE 6(8): e23470. doi:10.1371/journal.pone.0023470
  • Sweany, R.R., Damann Jr., K.E. and Kaller, M. D. 2011.  Comparison of Soil and Corn Kernel Aspergillus flavus Populations: Evidence for Niche Specialization. Phytopathology 101: 952-959

Select Presentations/Abstracts:

  • Poster presenter at APS Annual Meeting in Austin, TX.  Sweany R. R., Clark C. A., Villordon A. O.  2013.  Effect of viruses and water-stress on storage root initiation in sweetpotatoes. Phytopathology 103:S142.
  • Invited speaker at Corn Utilization and Technology Conference in Indianapolis, IN. Sweany, R. R.  2012.  Aspergillus Flavus Niche Specialization in Louisiana Corn Fields.
  • Presenter at National Sweetpotato Collaborators Group Annual Meetingin Birmingham, AL. Sweany, R.R., Picha, D.H., and Clark, C.A.  2012. Evaluation of Postharvest Hot Water Treatments and Bio-control Agents for Suppression of Rhizopus Soft Rot on Sweetpotatoes.
  • Presenter and moderator at APS Annual Meeting in Charlotte, NC. Sweany, R.R. and K.E. Damann.  2010. A comparison of soil and corn kernelAspergillus flavus populations: Evidence for niche specialization. Phytopathology 100:S124.
  • Presenter at APS Annual Meeting in Portland, OR.  Sweany, R.R., and Damann, K. E.  2009.  Comparison of aflatoxigenicity of corn kernel and soil populations of Aspergillus flavus. Phytopathology 99(6): S126.

Awards and Honors:

  • 2009: C. W. Edgerton Honor Award in Plant Pathology, awarded as outstanding graduate student in LSU Plant Pathology and Crop Physiology Department.
  • 2009: Louisiana State University Graduate Student Travel Award, awarded to graduate students from LSU to pay for travel expenses to professional meeting in     order to present data collected at LSU
  • 2009: John S. Niederhauser Student Travel Award, a competitive travel award to attend the Annual Meeting of the American Phytopathology Society in Portland, OR, August 2009.
  • 2003: Magna cum Laude, Bachelor of Science at LSU
  • 2001-2003: Forest Wildlife and Fisheries Alumni Scholarship
  • 2002-2003:  Chancellor’s List at LSU
  • 2002: LSU Campus Lake Enhancement Community Learning Plan 2ndwritten, 3rd place overall presentation
  • 2001-2002: Dean’s List at LSU
  • 2001: Honors for Grade Point Average Achievement in Microbiology, Basic Sciences Honors Convocation
  • 1998-2000:  Chancellor’s List at LSU
  • 2000: George Robertson Award, Phi Kappa Phi Honorary Society
  • 2000: Foureaux Society, awarded for achieving a 4.0 as a full-time student for the first 4 semesters as an undergraduate student at LSU.
  • 1998-2002:  Louisiana’s Taylor Opportunity Program for Students, Performance Award. Full tuition plus $400.