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Neal Stewart

Racheff Chair of Excellence and Professor of Plant Science



Agricultural and environmental plant biotechnology and genomics.  Of special interest relative to the GST program are three areas of research:

The genomics of weedy and invasive plants. We wish to answer questions about what genes make weeds weedy, and how certain weeds have been able to evolve herbicide resistance.

Extremophyte genomics.  Extremophytes are plants with extreme traits ( and we are part of the Thousand Plant Transcriptome project (

What genes are important for the particular extreme properties?

Bioenergy and bioproducts. We are interested in how switchgrass produces cell walls and how they can be disassembled. We are the project lead for the BioeEnergy Science Center in switchgrass biotechnology.

Description of Research

Neal Stewart's lab participates in the interfaces between environmental biology, functional genomics, biotechnology, with plants being at the core of the reserach. The Stewart lab is especially interested in agricultural applications of biotechnology and genomics. The effects of gene flow from transgenic crops to weeds have long been researched with an emphasis now in understanding the consequences of transgene introgression and competition on wild plants. That research has recently led the lab into investigations of the functional genomics of weeds and wild plants. Of special interest are understanding mechanisms of aluminum tolerance, the evolution of herbicide tolerance, and the genomics underlying weediness traits. Another facet of the lab is focused on producing plants to sense pathogens and chemicals in the environment and using reporter genes for detection and monitoring. This and the previous topic (weed genomics) have prompted new interests in comparative genomics: using microarrays to examine the varieties of transcriptional responses to a range of bacteria, fungi, and xenobiotics, as well as comparing responses among species of plants. In addition, the Stewart lab is participating in collaborative research in phytoremediation, biological and agricultural security, and will soon be adding a bioenergy focus. In conclusion, our research is almost always multidisciplinary and collaborative in nature and spans from molecular to ecological.


  • PhD: Virginia Polytechnic Institute and State University (1993)


Yuan, J.S., L.G. Abercrombie, Y. Cao, M.D. Halfhill, X. Zhou, Y. Peng, J. Hu, M.R. Rao, G.R. Heck, T.J. Larosa, R. D. Sammons, R. N. Trigiano, X. Wang, P. Ranjan, D. H. Johnson, P. A. Wadl, B.E. Scheffler, T.A Rinehart, R.N. Trigiano, C. N. Stewart, Jr. 2010. Functional genomics analysis of horseweed (Conyza canadensis) with special reference to the evolution of non-target-site glyphosate resistance. Weed Science. 58: 109-117.

Peng, Y., L.L.G. Abercrombie, J.S. Yuan, C.W. Riggins, R.D. Sammons, P.J. Tranel, and C.N. Stewart, Jr. 2010.  Characterization of the horseweed Conyza canadensis transcriptome using GS-FLX 454 pyrosequencing and its application for expression analysis of candidate non-target herbicide-resistance genes. Pest Management Science 66: 1053-1062.

Riggins, C.W., Y. Peng, C. N. Stewart, Jr., and P. J. Tranel. 2010. Characterization of de novo waterhemp (Amaranthus tuberculatus) transcriptome using GS-FLX 454 pyrosequencing and its application for studies of herbicide target-site genes. Pest Management Science 66: 1042-1052.

Stewart, C.N., Jr. (Ed.) 2009. Weedy and Invasive Plant Genomics, Blackwell Publishing, Ames Iowa. 288 pp.

Rao, M.R., M.D. Halfhill, L.G Abercrombie, P. Ranjan, J.M. Abercrombie, J.S. Gouffon, A.M. Saxton, and C.N. Stewart, Jr. 2009. Phytoremediation and phytosensing of chemical contaminants, RDX and TNT: identification of the required target genes. Functional and Integrative Genomics 9:537-547.

Burris, J.N., D.J.G. Mann, B.L. Joyce, C.N. Stewart, Jr. 2009. An improved tissue culture system for embyrogenic callus production and plant regeneration in switchgrass (Panicum virgatum L.). BioEnergy Research 2: 267-274

Mazarei, M., I. Teplova, M. R. Hajimorad and C. N.  Stewart, Jr. 2008. Pathogen phytosensing: plants to report plant pathogens, Sensors 8: 2628-2641.

Yuan, J.S., K.H. Tiller, H. Al-Ahmad, N.R. Stewart, C.N. Stewart, Jr. 2008. Plants to power: bioenergy to fuel the future. Trends in Plant Science 13: 421-429.

Abercrombie, J.M., M.D. Halfhill, P. Ranjan, M.R. Rao, A. Saxton, J.S. Yuan, and C.N. Stewart, Jr. 2008. Transcriptional responses of Arabidopsis thaliana to As(V) stress. BMC Plant Biology 8: 87 (

Stewart, C.N., Jr. 2007.  Biofuels and biocontainment. Nature Biotechnology 25:283-284.

Contact Information

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