Date: 16 July 2015
Author: Sarah Knapton, Science Editor
Resarch shows that releasing moths which only produce male offspring causes population crashes
Genetically engineered moths could be released in Britain to prevent devastating damage to broccoli and kale crops, scientists have claimed.
Researchers from Oxford University spinoff Oxitec, have tweaked the genes of the insects so that they only produce male offspring.
Tests in greenhouses have shown that releasing GM diamondback or cabbage moths causes populations to crash quickly, limiting damage from caterpillars. New results show that levels had been controlled within just eight weeks.
Now scientists are set to carry out new outdoor trials in New York State after gaining approval from the US Department of Agriculture.
“We all share an interest in safe and environmentally friendly pest control, so this is a very promising tool that could be put to good use by farmers as part of integrated pest management (IPM) strategies for healthy and sustainable agriculture.”
The self-limiting gene technique has already been trialled against dengue fever-carrying mosquitos, successfully reducing their populations by over 90 per cent in Brazil, Panama and the Cayman Islands
The engineered male moths are released to mate with the pest females, and because their female offspring do not survive to reproduce, the number of pest moths dwindles.
Diamondback moths cause a huge headache for UK farmers and the problem is only likely to worsen with climate change. The pest is also developing resistance to pesticides leading to growing concerns about how farmers will protect their crops in the future.
Diamondback moth caterpillars can devastate crops
Prof Joe Perry, Chair of the European Food Safety Authority GMO panel which decides on whether GM techniques can be used in Europe said that self-limiting gene techniques had been shown to carry few risks but said there would need to be a risk assessment before they could be used in Britain.
“There are relatively few risks foreseen with these mass-sterile techniques, which have been employed for decades using non-GM insects,” he said,
“However, it is important to realise that the mass release of insects is likely to affect the plants on which they feed, not all of which will be crop plants. This might conceivably favour the spread of some cruciferous weeds, hence the need for proper environmental risk assessment.”
GeneWatch UK claim the moths would be impossible to recall if anything went wrong but scientists said they were optimistic about the findings and future trials.
Prof Huw Jones, Head of Cereal Transformation Lab at Rothamsted Research, said: “Assuming environmental risk assessments were positive, I could see this becoming part of a future sustainable, integrated management strategy for agricultural regions where crops are regularly decimated by pest insects.”
Prof Johnjoe McFadden, Professor of Molecular Genetics at the University of Surrey, added: “The Oxitec group’s research provides an exciting new technology that could be used to control insect pests of plants, humans and animals.”