Change one gene, plants get healthier.

Souping up the NPR1 gene can turn an average laboratory mustard plant into a lean, mean, disease-fighting machine that laughs off a broad range of menaces.

Plants that have been genetically engineered to produce additional amounts of NPR1's protein show extra resistance to attack by both a fungus and a bacterium, say researchers at Duke University in Durham, N.C. Xinnian Dong and her colleagues report their findings in the May 26 Proceedings of the National Academy of Sciences.

NPR1, a key regulator, seems to marshal an army of other genes to fight pathogens. Even a moderate increase in NPR1's protein boosted plant resistance dramatically, the researchers say. They noticed no harmful side effects from the increased concentrations of the protein. "Thus, for the first time, a single gene is shown to be a workable target for genetic engineering of nonspecific resistance in plants," the team writes.

The dream of a good-health gene glows particularly bright because scientists have already found genes similar to mustard NPR1 in major commercial crops, including corn, wheat, canola, and tobacco.