Genetically engineered moths created to save crops without pesticide

Signal of change / Genetically engineered moths created to save crops without pesticide

By Juliette Aplin / 28 Jul 2015

Scientists at the UK-based company Oxitec claim to have successfully developed a ‘non-toxic’ and ‘pesticide-free’ approach to agricultural pest control. Instead of focusing on conventional methods such as pesticides, or genetically modifying crops to be more resilient to pests, Oxitec sought to change the genetic makeup of the pest itself.


In a paper published in the journal 'Insect Molecular Biology’, Oxitec details the genetic modification of the Diamondback moth, a global pest attacking brassica crops such as cabbages and cauliflowers. It is estimated that this pest costs farmers approximately $1bn a year to control.


The team of scientists identified a specific ‘self-limiting’ gene in the male moths, which is passed onto female offspring, who are then unable to survive to adulthood. The modification prevents the moths from reproducing, triggering a decline in the population.


Dr Neil Morrison, lead scientist in Oxitec’s Diamondback moth project sees this genetic technology as “providing a safe and sustainable form of insect control."


Genetically modified moths are currently be used in field cage tests in the UK, with small-scale field releases planned in the future.  


Signal Spotted by Anna Birney


Image Credit: CSIRO Science / wikimedia

So what?

Rising global demand for food, environmental changes and insecticide resistance are placing increasing pressure upon agricultural production.  As the negative consequences of using chemical pesticides and leeching are increasingly understood, focus within the agricultural industry has turned towards developing pest control methods that limit the impact on wider ecosystems.


Oxitec claims the genetic modification does not affect other species or the wider environment, stating that the ‘self-limiting’ gene can be eaten by birds or other animals with no adverse effects.

The use of GM technology for pest control builds upon Oxitec’s earlier work genetically modifying mosquitos in Brazil as a method preventing the spread of diseases such as dengue fever and malaria. Three million GM mosquitos were released in the Cayman Islands in 2009 and 2010 (a British Overseas Territory with no biosafety laws). However further trials in Brazil, Vietnam and the US have been delayed pending regulatory assessments and opposition from groups including Genewatch and Friends of the Earth.


As Helen Wallace, Executive Director of Genewatch, UK commented to the BBC, “the long-term effects of releasing millions of GM insects would be impossible to predict”. It's also unknown how a sudden decline in the moth population could impact the wider ecosystem.


While genetically modified pests may revolutionise the protection of crops, there may be unintended consequences.



What might the implications of this be? What related signals of change have you seen?

Please register or log in to comment.