Education
(90% Research, 10% Teaching)
- B.S., National Taiwan University (Entomology), 1959
- M.S., McGill University (Entomology), 1965
- Ph.D., McGill University (Entomology), 1968
Relevant Employment History
- Professor (1968-present), University of Florida
- Associate Professor (1982-1986), University of Florida
- Assistant Professor (1980-1982), University of Florida
- Assistant Professor (1974-1979), Oregon State University
- Research Associate (1969-1974), Oregon State University
- Postdoctoral Fellow (1968-1969), Cornell University
- Research Assistant (1963-1968), McGill University
- Research Entomologist (1961-1962), Taiwan Sugar Co.
Research Responsibilities
- Investigate biochemical mechanisms of insecticide resistance at the molecular level and use the knowledge gained to manage resistance.
- Understand detoxification mechanisms in insects at the molecular level and use the knowledge gained to design more effective methods of pest control.
Teaching Responsibilities
Teach a graduate level course, Insect Toxicology, and supervise graduate student's research.
Accomplishments
- Demonstrated that various host plants and allelochemicals induced different detoxication enzymes resulting in changing insecticide susceptibility in phytophagous insects.
- Developed a liquid chromatographic method to measure permethrin esterase activity in phytophagous insects using unlabeled trans-permethrin as substrate.
- Identified biochemical mechanisms underlying insecticide resistance in fall armyworms, diamondback moths, and cockroaches.
- Demonstrated the mode of inheritance of pyrethroid/carbamate resistance and microsomal oxidases in the diamondback moth.
- Demonstrated the mode of inheritance of carbaryl resistance and microsomal oxidases in the fall armyworm.
- Characterized beta-glucosidase in the fall armyworm, corn earworm, cabbage looper and velvetbean caterpillar.
- Purified and characterized glutathione transferases from the fall armyworm, corn earworm, tobacco budworm, cabbage looper and velvetbean caterpillar.
- Demonstrated that insecticide synergists (methylenedioxyphenyl compounds) eliminated enzyme induction caused by allelochemicals in fall armyworm larvae.
Grants and Contracts: (Total: $ 310,350 over the last 5 years)
- USDA (SRPIAP), 1990-1992
- National Science Council, Taiwan, 1990 -1991
- Sandoz Crop Protection Corp., 1992-1994
- S.C. Johnson Wax, 1993-1994
- NSF, 1988-1989, 1990-1994
- DuPont Agricutural Products, 1996 -1998
Career Publications
- Refereed papers: 92
- Chapter in Books: 6
- Reviews: 1
- Nonrefereed papers: 8
Selected Publications
Yu, S. J. 1984. Interaction of allelochemicals with detoxifying enzymes of insecticide- susceptible and resistant fall armyworm. Pestic. Biochem. Physiol. 22: 60- 68.
Yu, S. J. 1985. Consequences of induction of foreign compound- metabolizing enzymes in insects. In "Molecular Aspects of Insect-Plant Associations" (L. B. Brattsten and S. Ahmad, eds.), pp. 153-174. Plenum Press, New York.
Wadleigh, R. W. and S. J. Yu. 1987. Glutathione transferase activity of fall armyworm larvae toward alpha, beta - unsaturated carbonyl allelochemicals and its induction by allelochemicals. Insect Biochem. 17: 759 - 764.
McCord, E. M., Jr. and S. J. Yu. The mechanisms of carbaryl resistance in the fall armyworm, Spodoptera frugiperda (J. E. Smith). Pestic. Biochem. Physiol. 27: 114 -122.
Yu, S. J. 1989. Purification and characterization glutathione transferases from five phytophagous Lepidoptera. Pestic. Biochem. Physiol. 35: 97-105.
Yu, S. J. 1991. Insecticide resistance in the fall armyworm, Spodoptera frugiperda (J.E. Smith). Pestic. Biochem. Physiol. 39: 84-91.
Yu, S. J. 1992. Plant allelochemical-adapted glutathione transferases in Lepidoptera. In "Molecular Mechanisms of Resistance to Herbivorous Pests to Natural, Synthetic and Bioengineering Control Agents" (C.A. Mullin and J. G. Scott, eds.), pp. 174-190. Plenum Publ. Corp. New York.
Yu, S. J. and S. N. Nguyen. 1992. Detection and biochemical characterization of insecticide resistance in the diamondback moth. Pestic. Biochem. Physiol. 44: 74 -81.
Yu, S. J. and E. L. Hsu. 1993. Induction of detoxifying enzymes in phytophagous insects: Roles of insecticide synergists, larval age, and species. Arch. Insect Biochem. Physiol. 24: 21-32.
Yu, S. J. 1995. Tissue-specific expression of glutathione transferase isozymes in fall armyworm larvae. Pestic. Biochem. Physiol. 53; 164-171.
Yu, S. J. 1995. Insect glutathione transferases. Zool. Studies 35: 9-19.
Valles, S. M. and S. J. Yu. 1996. Biochemical mechanisms responsible for stage-dependent propoxur tolerance in the German cockroach. Pestic. Biochem. Physiol. 54: 172-180.
Yu, S. J. and S. N. Nguyen. 1998. Purification and characterization of carboxylamidase from the fall armyworm, Spodoptera frugiperda (J.E. Smith). Pestic. Biochem. Physiol. 60, 49-58.
Yu, S. J. 1999. Induction of new glutathione S- transferase isozymes by allelochemicals in the fall armyworm. Pestic. Biochem. Physiol. 63: 163-171.
Yu, S. J. and S. W. Huang. 2000. Purification and characterization of glutathione S- transferases from the German cockroach, Blattella germanica (L.). Pestic. Biochem. Physiol. 67: 36 -45.
Yu, S. J. and G. E. Abo-Elghar. 2000. Allelochemicals as inhibitors of glutathione S- transferases in the fall armyworm. Pestic. Biochem. Physiol. 68: 173 -183.