Whiteflies are the scourge of many farms, damaging tomatoes, peppers, eggplants and other crops. Now, researchers in Britain report that a species of wild tomato is more resistant to the pest than its commercial counterparts.

The wild type, the currant tomato, is closely related to domestic varieties, “so we could crossbreed to introduce the resistance,” said Thomas McDaniel, a biologist and doctoral student at Newcastle University in England and a co-author of the study, published in the journal Agronomy for Sustainable Development. “Another method would be genetic engineering, if we identified the genes.”

The researchers studied Trialeurodes vaporariorum, a species of whitefly that often attacks tomatoes grown in greenhouses. Whiteflies damage tomato plants by extracting the plant’s sap, which contains vital nutrients; by leaving a sticky substance on the plant’s surface that attracts mold; and by transmitting viruses through their saliva.

But currant tomatoes have some sort of mechanism, yet to be understood, that repels whiteflies. “They seemed to move away every time they tried to sample the sap,” Mr. McDaniel said.