Genetically modified moths eliminate their wild counterparts by preventing them from reproducing
A new strain of genetically modified moths that annihilates their devastating crop cousins by preventing them from reproducing has been released in the wild in New York State.
The diamond back moth (Plutella xylostella) causes billions of dollars in damage to crops of the brassica genus, including cabbage, broccoli and cauliflower.
But the new strain, developed with the help of the Oxitec biotechnology company, based in Oxfordshire, is genetically engineered to prevent its female caterpillar offspring from surviving.
Using the new moths, Cornell University researchers successfully suppressed a population of diamonds in New York State, while preventing the development of insecticide resistance.
According to the researchers, the project paves the way for effective and sustainable pest control that is more environmentally friendly and at a much lower cost than insecticides.
The diamond loin moth (pictured) causes billions of dollars in damage to brassica crops such as cabbage and broccoli.
“When released in a field, self-limited male insects behaved similarly to their unmodified counterparts in terms of factors that are relevant for their future application in crop protection, such as survival and distance traveled,” he said. Professor Anthony Shelton in the Department of Entomology at AgriTech at Cornell University in New York.
“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,” said Dr. Neil Morrison, agriculture leader and joint study of Oxitec. Author.
The moths were designed using the ‘self-limited’ gene developed by Oxitec that disrupts the proper functioning of insect cells by excessively producing a protein in them.
“Since the self-limiting gene works using the insect’s own biology against itself, our control method provides a solution that only affects that particular species of pest without introducing harmful toxins,” says Oxitec on its website.
For the study, modified male moths were released at a research farm run by Cornell University in Geneva, New York, where they mated with wild pest females.
The moths, both engineering and wild, were recaptured in traps and the dispersion, persistence and survival in each field were measured.
“For the field study, we use the” mark-release-recapture “method, which has been used for decades to study the movement of insects in the fields,” said Professor Shelton.
The researchers found that wild females that mated with these ‘self-limited’ males could not produce viable female offspring, who died shortly after hatching.
The larvae of the Diamondback moth (Plutella xylostella) eat cabbage. The moth species is found in America, Europe, New Zealand and Asia.
They then used mathematical models to demonstrate that the release of modified males could offer effective pest management of P. xylostella on a broader scale
With the sustained releases of these manipulated moths, the pest population focuses in a sustainable way compared to the use of insecticides.
In addition, self-limited males do not have to have permanent effects on moth populations.
After the releases of genetically modified males stop, the affected insects decrease and disappear from the environment in a few generations.
While this may seem like a long time, a generation of diamond back can vary from 21 to 51 days, depending on the weather and food conditions.
The study, which was the first in the world to release self-limited agricultural insects in an open field, has been published in Frontiers in Bioengineering and Biotechnology.
The annual global insecticide market is projected to reach $ 19.27 billion by 2022, according to Statista
The research is based on the technique of sterile insects, releasing insects that cannot reproduce, to control insects that developed in the 1950s, using radiation.
The technique was also celebrated by Rachel Carson in her 1962 book Silent Spring, which documents the environmental effects caused by pesticides.
“The use of genetic engineering is simply a more efficient method to reach the same end,” said Professor Shelton.
Arthropod pests, including moths, cause an estimated loss of $ 470 billion in agricultural crops worldwide.
According to Statista, the main tool to control these pests is insecticides, whose global annual market for which it is projected will reach $ 19.27 billion in 2022.
WHAT IS THE TECHNIQUE OF STERILE INSECTS?
The sterile insect technique is an ecological method for the control of insect pests.
It involves mass rearing and sterilization, by radiation, of a target pest.
This is followed by a release in the area of sterile males by air over defined areas.
Then they mate with wild females, which does not produce offspring and decreases the population of pests.
While they remain sexually competitive, affected insects cannot produce offspring.
The sterile insect technique does not involve transgenic processes (genetic engineering).
However, it is important to keep in mind that this new study by Oxitec and Cornell University does use transgenic techniques to control diamond back moths.
Source: International Atomic Energy Agency.