Barry J. Shelp

Barry Shelp
College Professor Emeritus
Adjunct Professor



519-824-4120 x53089


Hon B.Sc. Brock University;
M.Sc. Brock University;
Ph.D. Queen's University


Edmund C. Bovey Building


4237 ECB

My primary research is concerned with developing abiotic and biotic stress resistance in plants using genetic engineering strategies. My principal approach involves GABA (gamma-aminobutyrate), a ubiquitous 4-C, non-protein amino acid of uncertain function in plants. However, it does accumulate in response to a variety of abiotic and biotic stresses, including temperature and oxygen shock, as well as insect damage. We are continuing to identify the proteins involved in GABA metabolism and transport, and their corresponding genes, using state-of-the- art analytical tools and biochemical and molecular techniques. These genes are typically being expressed in recombinant expression systems, with the recombinant proteins being isolated and purified for biochemical and physical characterization. The genes are also being modified and reinserted by Agrobacterium-mediated transformation or particle bombardment. We are using various Arabidopsis mutants (overexpression, knockout, knockdown) to elucidate the physiological function and regulation of GABA metabolism, and the interactions among GABA metabolism, photorespiration, polyamines and the tricarboxylic acid cycle. Also, we are investigating the role of GABA in the onset of physiological disorders in tree fruit stored under controlled atmosphere conditions. In addition to manipulating GABA metabolism, we are collaborating in studies of N use efficiency and carotenoid metabolism.

To view Dr. Shelp's citations, click here.


Greenhouse Canada logoGreenhouse Canada magazine selects a paper from Dr. Shelp’s team as Editors’ Pick for December 2020.

More for less: Lowering N, P and K in mums
Barry J. Shelp, Edward J. Flaherty, William J. Sutton, Skye Duncan Stephens, Alyna J. Donetz, Lou M. Schenck and Jamie Aalbers

The paper is available on the home page for Greenhouse Canada magazine:


Canadian Journal of Plant Science logoCanadian Journal of Plant Science selects a paper from Dr. Shelp’s team as "Editor's Choice" for June 2020.

Strategic timing and rate of phosphorus fertilization improves phosphorus-use efficiency in two contrasting cultivars of subirrigated greenhouse-grown chrysanthemum

Barry J. Shelp, William J. Sutton, Edward J. Flaherty
This initiative of Canadian Science Publishing and the Canadian Journal of Plant Science is a means of highlighting articles of particularly high caliber and topical importance.

The paper is available on the home page for CJPS as the Editor’s Choice:


Greenhouse Canada logo

Greenhouse Canada magazine selects discussion paper by Van Cauwenberghe and Shelp as Editors’ Pick for June 2020.  

Advancing cannabis genetics in Canada. The case for a cannabis germplasm repository.
Owen R. Van Cauwenberghe and Barry J. Shelp

The paper is available on the home page for Greenhouse Canada magazine:



Relevant Links:

Selected Publications:

Trobacher, C.P., S.M. Clark, G.G. Bozzo, R.T. Mullen and B.J. Shelp. (2012). Catabolism of GABA in apple fruit: Subcellular localization and biochemical characterization of two γ-aminobutyrate transaminases. Postharvest Biology and Technology. 75: 106-113.

Shelp, B.J., G.G. Bozzo, C.P. Trobacher, A. Zarei, K.L. Deyman and C.J. Brikis. (2012). Review/hypothesis: Contribution of putrescine to 4-aminobutyrate (GABA) production in response to abiotic stress. Plant Science. 193: 130-135.

Shelp, B.J., G.G. Bozzo, A. Zarei, J.P. Simpson, C.P. Trobacher and A.L. Allan. (2012). Strategies and tools for studying the metabolism and function of γ-aminobutyrate in plants. II. Integrated analysis. Botany. 90: 781-793.

Shelp, B.J., R.T. Mullen and J.C. Waller. (2012). Compartmentation of GABA metabolism raises intriguing questions. Trends in Plant Science. 17: 57-59.

Allan, W.L., K.E. Breitkreuz, J.C. Waller, J.P. Simpson, G.J. Hoover, A. Rochon, D.J. Wolyn, D. Rentsch, W.A. Snedden and B.J. Shelp. (2012). Detoxification of succinate semialdehyde in Arabidopsis glyoxylate reductase and NAD kinase mutants subjected to submergence stress. Botany. 90: 51-61.

Allan, W.L., S.M. Clark, G.J. Hoover and B.J. Shelp. (2009). Role of glyoxylate reductases during stress: a hypothesis. Biochemical Journal. 423: 15-22.

Clark, S.M., R. Di Leo, P.K. Dhanoa, O.R. Van Cauwenberghe, R.T. Mullen and B.J. Shelp. (2009). Biochemical characterization, mitochondrial localization, expression, and potential functions for an Arabidopsis γ-aminobutyrate transaminase that utilizes both pyruvate and glyoxylate. Journal of Experimental Botany. 60: 1743-1757.

Allan, W.L., J.P. Simpson, S.M. Clark and B.J. Shelp. (2008). γ-Hydroxybutyrate accumulation in Arabidopsis and tobacco plants is a general response to abiotic stress: putative regulation by redox balance and glyoxylate reductase isoforms. Journal of Experimental Botany. 59: 2555-2564.

Hoover, G.J., O.R. Van Cauwenberghe, K.E. Breitkreuz, S.M. Clark, A.R. Merrill and B.J. Shelp. (2007). Characteristics of an Arabidopsis glyoxylate reductase: general biochemical properties and substrate specificity for the recombinant protein, and developmental expression and implications for glyoxylate and succinic semialdehyde metabolism in planta. Canadian Journal of Botany. 85: 883-895.

Shelp, B.J., A.W. Bown and D. Faure. (2006). Extracellular γ-aminobutyrate mediates communication between plants and other organisms. Plant Physiology. 142: 1350-1352.

Bown, A.W., K.B. MacGregor and B.J. Shelp. (2006). Gamma-aminobutyrate: defence against invertebrate pests? Trends in Plant Science. 11: 424-427.

Chevrot, R., R. Rosen, E. Haudecoeur, A. Cirou, B.J. Shelp, E. Ron and D. Faure. (2006). GABA controls the level of quorum-sensing signal in Agrobacterium tumefaciens. Proceedings of the National Academy of Sciences. 103: 7460-7464.