"We wouldn't expect herbicide tolerance to give a plant an ecological advantage," she said.
Genetically modified (GM) crops show no signs of turning into super-weeds, according to a 10-year study.
Researchers planted GM varieties of oilseed rape, potato, maize and sugar beet alongside conventional crops in 12 different areas in the UK to see whether the GM plants could invade natural habitats.
Reporting their findings in the science journal Nature, the researchers said most of the crops died out after four years, and after 10 years the only survivor was one type of non-GM potato.
'No surprise'
When the study began, the kinds of GM plants available were varieties engineered to make them better able to withstand spraying with herbicides or insect attack.
One of the report's authors, Rosemary Hails, told BBC News Online that the results came as no surprise, as such traits were unlikely to help a plant survive in the wild.
"We wouldn't expect herbicide tolerance to give a plant an ecological advantage," she said.
The report's authors stress that they only looked at specific kinds of GM crop and did not look at new crops engineered to withstand drought or natural pests.
"Our results do not mean that other genetic modifications could not increase weediness or invasiveness of crop plants, but they do indicate that arable crops are unlikely to survive for long outside cultivation," they wrote in Nature.
"We will always have to be careful about managing crops and about spraying regimes to ensure that we don't end up with varieties in places we don't want them," Dr Hails added.
Industry welcome
The scientific group CropGen, which is backed by the crop industry, welcomed the study.
"These results confirm what many plant geneticists and ecologists have long expected: that super-weeds are not lurking round the corner of every GM plantation," CropGen's Professor Howard Slater said.
Adrian Bebb, food campaigner at FoE, said: "They add to our knowledge on the survival of crops in the wild.
"However, the research provides no guarantee that GM super-weeds will not establish themselves in the wider environment.
"This risk will increase significantly if the government succeeds with its plans to conduct GM trials at over 90 sites throughout the UK," he added.