New Chemical Pesticide Targets Parasitic Nematodes with Lower Toxicity Risks to Humans, Wildlife

Researchers created a new chemical pesticide that has lower risks of toxicity to people and animals while still being effective against parasitic worms nematodes.

Parasitic Nematodes vs. New Chemical

The most prevalent critters on farms, as well as everywhere on land, are tiny worms known as nematodes.

While some are good for the soil, others parasitize crops and cause over a hundred billion dollars in losses annually.

Pesticides cause collateral damage to other forms of life even though they can eradicate dangerous nematodes.

Researchers have now found a brand-new substance that selectively eliminates dangerous nematodes while posing considerably less of a threat to people and other animals.

Tim Geary, a parasitologist at Queen's University Belfast and McGill University who was not involved in the creation of the chemical, commented that this is special because it might provide a means of enhancing crop pest control.

Highly Toxic Pesticides

The American Phytopathological Society states that the frequently used pesticides that are known to kill nematodes have been outlawed due to their toxicity to people and wildlife.

Methyl bromide, a common chemical used to fumigate soils, started to be phased out by chemical producers in 2004 because it depletes the ozone layer on Earth.

Since then, chemical manufacturers have created several fresh, safer worm insecticides.

The most recent contender is from the University of Toronto's (U of T) lab of chemical geneticist Peter Roy.

He and his colleagues have recently examined 100,000 tiny compounds to determine whether they are capable of killing Caenorhabditis elegans, a non-pathogenic nematode.

Andrew Burns, a University of Toronto biochemical geneticist, and colleagues determine whether a chemical is harmful to other types of animals, such as fungi, insects, and mice if it is found to be toxic to C. elegans.

The team is not seeking chemicals that will kill everything, according to Burns.

Pesticides Levamisole and Selectivin

Burns became curious about a substance in 2016 that passed those tests.

Its chemical composition was similar to that of levamisole, a medication used to treat animals infected with parasitic nematodes, but the compound's effects on the worms were different.

Levamisole paralyzes them whereas selectivin, a recently discovered tiny chemical, instantly kills them.

Additional research uncovered selectivin's fatal techniques.

Once it has been absorbed by the nematode, the worm changes it using cytochrome P450 enzymes, which are found in many animals and are used to detoxify foreign compounds.

But for whatever reason, the nematode cytochrome P450 converts selectivin into a poisonous substance.

Burns theorized that selectivin would be useful for killing nematodes that reside in the soil since the soil has a lot of oxygen and Cytochrome P450, which needs oxygen to function.

New Pesticide

According to Charles Opperman, a North Carolina State University nematologist, a new pesticide that kills the plant-parasitizing nematodes but spares the helpful nematodes might be advantageous.

He claimed that it would give growers additional options for preserving the health of their soil.

Next, the team worked with scientists from the US Department of Agriculture to test a nematode known for its bad reputation, Meloidogyne incognita, which infects a variety of crops.

The researchers found that selectivin had comparable or slightly improved nematode control in studies using greenhouse tomato plants.

Selectivin may be easier to manufacture than other nematode-targeting insecticides, which is another benefit.

The required chemical processes could be carried out without costly catalysts or extreme temperatures, instead just by using just two inexpensive solvents, Science reports.

The study by Burns, Roy, and several colleagues was published in the journal Nature.