Andrew Stephenson is interested in answering that question. He’s a plant ecologist at Penn State University. Plant breeders put things called transgenes into plants to give them desirable properties such as disease resistance.
“People were concerned that when the transgene escapes into the wild populations, it will provide a fitness advantage,” says Stephenson.
A fitness advantage means the wild plants, with this advantageous transgene, might grow out of control, mucking up the ecosystem.
Meet The Cucurbita
Stephenson studies a wild squash plant called cucurbita, the Texas gourd. It looks like a pumpkin plant, but with smaller leaves. The fruits are about the size of a baseball or softball, they’re round or slightly pear-shaped, and they taste terrible.
Cucurbita shows up throughout the American Southwest and Mexico. Stephenson wanted to know what would happen when his wild gourd picked up a transgene that’s used in cultivated squash to protect the crop from plant viruses.
So he purposely created a strain of Texas gourd with the transgene, and planted some next to the same gourd that didn’t have the transgene. Then he waited for spring, when aphids would bring a plant virus to the field.
Stephenson reports in the journal PNAS that as the virus spread through the field, it only affected the Texas gourd without the transgene.
