James Frazier, Ph.D.

Department Focus Areas

Chemical Ecology

Research

Insect chemoreception; chemically mediated behavior; insect-plant interactions

Research Activities & Interests

My research focuses on the structure and functioning of insect chemosensory systems and on chemically mediated behavior, especially the feeding behavior of caterpillars. I am seeking to understand the sensory messages that cause a caterpillar to initiate feeding as well as those that prevent feeding, even in the presence of an acceptable host plant. The key stimuli that caterpillars detect and respond to during the early phases of induced plant defenses are also being investigated. A second area of interest is in the basic sensory transduction machinery that insect chemosensory cells use to operate. We are using pharmacological agents, genetic mutants, and combined electrophysiological and ultra-rapid freezing techniques to investigate the mechanisms of transduction in chemosensory cells. Details of the operating mechanisms of these cells are being used to understand plant induced defenses, design new antifeedant chemicals, and for the development of new detectors for use in Precision Agriculture.

Relevant Publications

Mullin, C.A., S. Chyb, H. Eichenseer, B. Hollister, J. L. Frazier. 1994. Neuroreceptor mechanisms in insect gustation: A pharmacological approach. J. Insect Physiol.

Mullin, C.A., H. Eichenseer, B. Hollister, S. Chyb, and J. L. Frazier. 1995. GABA/Glycine meuroreceptors may mediate taste perception of antifeedants and insecticides in Diabrotica virgifera virgifera. Pesticide Sci. 43:371-375.

Frazier, J.L. and S. Chyb. 1995. Use of feeding inhibitors in insect control. Chapter 13. In G. deBoer and R.F. Chapman (eds.), Regulatory Mechanisms of Insect Feeding. Chapman and Hall. 364-382.

Chyb, S., C.A. Mullin, B. Hollister, H. Eichenseer and J.L. Frazier. 1995. Identification of contact chemosensilla involved in taste mediation of adult western corn rootworm (Diabrotica virgifera virgifera LeConte). J. Chem. Ecol. 21(3):313-329.

Hanson, F.E. J.L. Frazier, J. Stitt, and S. Chyb. 1996. Modeling the insect feeding decision system: a new approach utilizing fuzzy system theory. Entomol. Exptl et Appl. 80:109-112.

Stitt, J.P. R.P. Gaumond, J.L. Frazier, and F.E. Hanson. 1997. An Artificial Neural Network for Neural Spike Classification. Proceedings of the IEE 23rd Annual Northeast Bioengineering Conference. 15-16.

Stitt, J., J.L. Frazier, F.E. Hanson and R. Gaumond. 1998. Insect sensory action potential classifiers: Functional comparisons of template matching, principle components analysis, and artificial neural networks. Chemical Senses. 23(5):531-539.

Stitt, J.P. R.P. Gaumond, J.L. Frazier, and F.E. Hanson. 1998. Automated Analysis of Feeding Behavior in Small Animals. Proceedings of the IEE 24th Annual Northeast Bioengineering Conference. 120-123.

Tallamy, D.W., J.L. Frazier, and C.A. Mullin. 1999. An alternate route to insect pharmacophagy: the loose receptor hypothesis. J. Chem. Ecol. 25:1987-1997 l