Genetically engineered moth released into the wild could save countless crops

Researchers have tinkered with the genetics of a common moth to create a more effective and sustainable type of pest control for farmers.

The future of pest control could involve genetically engineered moths, according to new research from Cornell University. Publishing to Frontiers in Bioengineering and Biotechnology, scientists said they have successfully released a ‘tweaked’ diamondback moth into the wild.

The original moth is highly damaging to brassica crops such as cabbage, broccoli, cauliflower and canola. However, this new strain of moth, developed by a biotechnology company called Oxitec, is self-limiting and is modified to control its pest counterparts in the field.

After males of this strain are released, they find and mate with pest females, but the self-limiting gene passed to offspring prevents female caterpillars from surviving. Over time, the pest population is reduced. After releases have stopped, the insects decline and disappear from the environment in a few generations.

“When released into a field, the self-limiting male insects behaved similarly to their non-modified counterparts in terms of factors that are relevant to their future application in crop protection, such as survival and distance travelled,” said Prof Anthony Shelton, who led the research.

“In laboratory studies they competed equally well for female mates. Our mathematical models indicate that releasing the self-limiting strain would control a pest population without the use of supplementary insecticides, as was demonstrated in our greenhouse studies.”

The research was based on the sterile insect technique for managing insects developed back in the 1950s. However, Shelton said that “using genetic engineering is simply a more efficient method to get to the same end”.

Dr Neil Morrison, Oxitec’s agriculture lead and study co-author, added: “This study demonstrates the immense potential of this exciting technology as a highly effective pest management tool, which can protect crops in an environmentally sustainable way and is self-limiting in the environment.”