BY BLOCKING production of a natural chemical, genetic engineers have created
tobacco plants that are super-resistant to aphids. A related approach could one
day persuade plants to produce valuable compounds such as fragrances and drugs,
the researchers say.
Many flowering plants have tiny glands called trichomes that secrete
substances onto leaf surfaces. George Wagner and his colleagues at the
University of Kentucky in Lexington tinkered with an enzyme in tobacco trichomes
that completes the production of an aphid-repelling substance called
cembratriene-diol. Strangely, the diterpene precursor from which this repellent
is made is even more potent, which is why Wagner wanted…
