Department of Your Department

Student of the Month (March 2009)


Name: Piyum Khatibi(khatibpa at vt.edu)

Research project: Mitigating Deoxynivalenol Contamination in Hulless Barley and Fuel Ethanol Co-products

Advisor: David Schmale

Departmental affiliation: PPWS

Anticipated defense date: 2011

Project description:

Hulless barley (HLSB) is a new and emerging crop in Virginia, and may be an important source of fuel ethanol in the future. Dried distiller's grains with solubles (DDGS), a nutrient rich co-product of fuel ethanol fermentation, are rapidly becoming one of the main sources of feed for domestic animals. One of the current problems plaguing the barley industry is a dangerous mycotoxin called deoxynivalenol (DON), produced by the fungus Fusarium graminearum. DON is toxic to humans and domestic animals in very small amounts, causing vomiting, reproductive problems, feed refusal, and even death. An approach to mediate the threat of DON is to transform barley with a 3-O-acetyltransferase (TRI101), which catalyzes the acetylation of DON at the third carbon, reducing the toxicity of DON by two orders of magnitude. This strategy of detoxification may reduce the threat of mycotoxin contamination in DDGS. The specific objectives of my research are to: (1) measure natural DON resistance in a series of wild-type Virginia hulless barley lines, (2) assess the tissue culture competence of wild-type Virginia hulless barley lines, (3) determine the detoxification efficiency of TRI101 cloned from different Fusarium species, (4) engineer barley to express TRI101 in an effort to reduce DON in harvested grain, and (5) track the concentration of DON in DDGS following ethanol production from both wild-type and transgenic barley expressing TRI101. This work will impact commercial growers and producers of barley and ethanol, ensure a safe supply of feed for domestic animals, and create a new model system for reducing mycotoxin contamination in staple foods and feeds worldwide.

Publications:

  • Roney, J. K., P. A. Khatibi, and J.H. Westwood. (2007). "Cross-species translocation of mRNA from host plants into the parasitic plant dodder." Plant Physiol 143(2): 1037-43.
  • Westwood, J. H., J. K. Roney, P.A. Khatibi, and Verlyn K. Stomberg (2009). "RNA translocation between parasitic plants and their hosts." Pest Manag Sci 65(5): 533-9.

Publications in Progress:

  • Khatibi, P.A., S. Liu, W.S. Brooks, D.G. Schmale, and C.A. Griffey. 2009. "Resistance to Fusarium head blight and deoxynivalenol accumulation in Virginia barley." Manuscript in preparation.

Posters Presented:

  • P.A. Khatibi, D.G Schmale, W.S Brooks, and C.A. Griffey. (2007). "Reducing DON Potential in Virginia Hulless Barley Lines through Genetic Engineering." In Proceedings of the 2007 National Fusarium Head Blight Forum, Kansas City, MO.
  • P.A. Khatibi, S. McCormick, N. Alexander, D.G. Schmale. (2008). "Bioprospecting for TRI101 in Fusarium: Searching for a Better Enzyme to Detoxify Deoxynivalenol (DON)." In Proceedings of the 2008 National Fusarium Head Blight Forum, Indianapolis, IN.

Talks and Presentations:

  • P.A. Khatibi. (2007). "Engineering Barley to Detoxify Deoxynivalenol: Managing Mycotoxins in DDGS, a Byproduct of Biofuels Production." Virginia Tech Plant Pathology, Physiology, and Weed Science Departmental Seminar., December 2007. Blacksburg, VA.
  • P.A. Khatibi, C.A. Griffey, and D.G Schmale. (2009). "Mitigating Deoxynivalenol Contamination in Hulless Barley and Ethanol Co-products." 2009 American Phytopathological Society Potomac Division Meeting, March 2009, Gettysburg, PA.
  • P.A. Khatibi. (2009). "Mitigating Deoxynivalenol Contamination in Hulless Barley and Fuel Ethanol Co-products." Virginia Tech Plant Molecular Biology Discussion Group Seminar, May 2009, Blacksburg, VA.

Memberships:

  • Gamma Sigma Delta, Honor Society of Agriculture
  • Phi Sigma, Biological Sciences Honor Society
  • American Phytopathological Society