INVASIVE white Italian snails in Australia are using mutated mucus enzymes to resist pesticides, posing a growing threat to the country’s agriculture, according to a new study.
Researchers discovered that trails left by the white Italian snail, Theba pisana, contained high levels of an enzyme that could neutralise pesticide toxins, making those “super snails” resistant to conventional control methods.
The findings were released Wednesday by the University of the Sunshine Coast (UniSC).
“This mutated enzyme has previously been found in insects like ticks and flies that have developed chemical resistance over time,” said UniSC PhD researcher and lead author Inali Lutschini. Its abundance in land snails, however, was unexpected.”
Co-author, Prof. Scott Cummins, a functional genomics expert at UniSC, said the team was now working to exploit the finding to develop better control strategies and reduce dependence on organophosphate pesticides, which could harm the environment and non-target species.
According to Cummins, the snails secrete the enzyme in large quantities through their slime, particularly when they are most active and vulnerable, during mating. This enzyme acts as a protective barrier against pesticides.
Invasive snails are a global issue, causing significant economic losses. In Australia alone, they inflict around AUD 170 million (USD 109 million) in annual damage to the grain industry.
Theba pisana, which has spread across southern Australia since the early 20th century, is small but reproduces rapidly, compounding the problem.
The findings, published in the international science journal PLOS One, highlight the snails’ growing resistance to molluscicides.
Researchers now hope that alternative strategies, such as biological or gene-based controls, including the use of spider venoms, could offer a solution, as some spider species prey on snails.
“Our research suggests that rotating different types of pesticides may be more effective than simply increasing concentrations,” Lutschini said.
“Snails can evolve defense mechanisms quickly, so we need smarter, more adaptable approaches.” (dpa/NAN)

