The wheat strain has been genetically engineered to give off pheromones mimicking insect alarms to scare away pests such as aphids while attracting their natural predators. It was successfully tested in the laboratory but it failed to repel damaging aphids during outdoor field trials.
The genetically modified wheat strain is developed is developed at Rothansted Research, and agricultural science institute with less need for insecticides.
Researchers said that in the field trials aphids still made a meal of the grain.
Toby Bruce, chemical ecologists at Rothamsted said, “The disappointing thing was when we tested it in the field we didn’t find any significant reduction [in aphids], we didn’t get the result that would have been useful in taking this forward. It was quite sad.”
Research team said that compared with a control crop of wheat, the GM crops showed no improved yields, no reduction in aphids and no increase in attacks by aphid predators such as wasps or ladybugs.
Aphids are a serious problem for wheat farmers, feeding on sap, and harvest in fields infested with aphids can be reduced significantly.
In the laboratory, the genetically modified strain showed promising results repelling three types of aphids and attracting parasitic wasps that are an aphid predator.
However, when the research moved to field trials, planting both engineered wheat and non-GM control strain in 16 test plots, the GM wheat failed to perform as expected.
In 2012, when the trials started, they drew protest by anti-GM campaigners who staged demonstrations at the Rothamsted trial site and threatened to destroy the crop that resulted in the need to make the site secure, adding around $2.8 million to the study’s $1.1 million research costs.
Researchers said, despite encouraging lab work, the results of the trials were unambiguous.
Chemical ecologist John Pickett, who led the work said, “The field is the ultimate arbiter, this hypothesis was tested false.”
Still, other experts in U.K. said the approach is still worth pursuing despite disappointing trials
Ottoline Leyser, a plant biologist at the University of Cambridge said, “We are in urgent need of new ways to control insect pests on crops, with very limited options available from pesticide sprays and conventional breeding. Alternative approaches ranging from new agricultural practices to genetic modification must be explored.”