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Updated: Aug 22, 2026

Transmitting Plant Viruses Using Whiteflies
Published on: November 8, 2013
Tryptophan Decarboxylase, Tryptamine, and Reproduction of the Whitefly
J. C. Thomas1, D. G. Adams, C. L. Nessler
1Department of Biochemistry (J.C.T., D.G.A., H.J.B.) and Department of Plant Sciences (J.K.B., H.J.B.), University of Arizona, Tucson, Arizona 85721.
Abstract:
Tryptophan decarboxylase (TDC) from Catharanthus roseus (periwinkle) converts tryptophan to the indole-alkaloid tryptamine. When the TDC gene was expressed in transgenic tobacco, the 55-kD TDC enzyme and tryptamine accumulated. Bemisia tabaci (sweetpotato whitefly) reproduction on transgenic plants decreased up to 97% relative to controls. Production of tryptamine, its derivatives, or other products resulting from TDC activity may discourage whitefly reproduction and provide a single-gene-based plant protection strategy.
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