How entomopathogenic nematodes are nature’s precision pest-control system

UK | Biocontrol

These tiny soil worms eliminate pests, saving billions in agriculture around the world.

11/20/2025

Entomopathogenic nematode.

Across every continent, from UK farmland to the Amazon rainforest, nature has engineered one of the most advanced biological pest-control systems on Earth. These defenders are not insects, birds, or fungi—they are entomopathogenic nematodes (EPNs): microscopic worms that track, infect and eliminate destructive soil-dwelling insect pests using a level of precision that rivals modern technology.

Though only a millimetre long, they silently prevent billions of dollars in global crop damage each year. And as agriculture moves away from chemical insecticides, these tiny worms are emerging as one of the most powerful tools for sustainable crop protection.

A Global Army Beneath Our Feet

EPNs occur naturally in soil worldwide, from temperate grasslands to tropical forests. They have co-evolved with insects for over 120 million years, specialising in hunting larval pests hidden in the soil—the stage where most insecticides fail to reach.

Many soil pests of economic importance can attack up to 50 different crop species, meaning each pest group can cause between $1–5 billion in global agricultural losses. Combined, soil-dwelling insects such as vine weevil, chafer grubs, leatherjackets, armyworms, cutworms and rootworms cause over $30 billion in damage annually.

EPNs have evolved to track these pests with remarkable accuracy.

How Nematodes Track Their Prey: CO₂ and Plant Chemical Signals

Soil is full of chemical signals, and nematodes use these to navigate. Two signals are vital:

1. CO₂ from insect respiration: Active larvae breathe and release CO₂, which diffuses through the soil.

Nematodes detect this gradient and rush toward the source—an elegant natural tracking system.

2. Plant chemical signals: beta-caryophyllene: When insects feed on plant roots, the damaged roots release volatile chemicals such as beta-caryophyllene.

A landmark Nature study showed that maize roots emit this compound when attacked by Diabrotica virgifera, the Western Corn Rootworm—a pest causing €1.5 billion of annual losses in Europe and several billion more globally.

This signal attracts nematodes to the exact feeding site, allowing them to eliminate the pest before root damage becomes severe.

Together, CO₂ and plant distress signals form one of nature’s most sophisticated pest-location systems.

The Infection Process: A Precision Strike

Once an EPN locates a host insect, the infection cycle begins:

1. Entry through natural openings: The nematode enters through the insect’s mouth, spiracles, or anus.

2. Release of symbiotic bacteria: Inside the body cavity, the nematode releases Xenorhabdus or Photorhabdus bacteria.

3. Rapid multiplication and toxin release: These bacteria overwhelm the insect’s immune system and kill it within 24–48 hours.

4. Reproduction inside the cadaver: The insect’s body becomes a “bioreactor,” producing up to 100,000 nematode offspring.

5. Emergence of a new generation: Once nutrients are consumed, the new nematodes exit and begin hunting again.

This is one of nature’s most efficient biological control cycles.

Real-World Success Stories

EPNs have been used successfully across multiple sectors:

Forestry – Pine Weevil Control. Pine weevil (Hylobius abietis) causes huge losses in reforestation. Field trials in the UK and Scandinavia showed high survival of young trees when EPNs were applied.

- Turf & Amenity – Leatherjackets and Chafer Grubs. Golf courses and sports turf suffer severe root damage from these pests. EPNs consistently deliver >80% suppression when applied under the right conditions.

- Soft Fruit & Ornamentals – Vine Weevil. Growers have used EPNs for over two decades to protect strawberries, nursery stock and ornamentals with excellent reliability.

Regulatory Freedom: Why EPNs Are Exempt

Entomopathogenic nematodes have one of the strongest safety records of any biological control agent:

• No toxicity to humans, wildlife or beneficial insects

• No residues on crops

• No groundwater contamination

• No risk of resistance development

As a result, the EU exempted EPNs from registration in 1984.

They can therefore be used:

• without restrictions

• in all crops

• at any time

• with zero pre-harvest interval

This regulatory advantage has driven adoption across Europe.

The Biggest Limitation: Shelf Life and Formulation

Despite their strengths, traditional EPN products suffer from:

• Short shelf life (8–10 weeks)

• Cold-chain requirements

• Sensitivity to temperature, oxygen, and desiccation

• Loss of viability during storage and transport

This is why 90% of global EPN use is in Europe, and only 10% in the rest of the world.

Bionema’s Encapsulated Formulation Technology

To solve this bottleneck, Bionema has developed encapsulated formulation technology that:

• Extends shelf life from 10 weeks to 6 months

• Protects nematodes from temperature stress

• Improves survival during transport

• Enables export to hot regions and long-distance markets

• Supports precision application in dry or variable soils

This innovation removes the most significant barrier to global EPN adoption.

Future Outlook: Nematodes in Regenerative Agriculture

EPNs already form a core part of Integrated Pest Management (IPM).

Their future role will expand because they:

• Reduce reliance on chemical insecticides

• Protect pollinators and beneficial insects

• Improve soil biodiversity and ecological balance

• Fit perfectly with regenerative agriculture principles

• Support national pesticide-reduction strategies

They can be used as a standalone biological control or combined with other natural solutions, giving growers a flexible, residue-free, sustainable tool.

Conclusion

Nature has engineered a pest-control system that is precise, safe and incredibly effective. Entomopathogenic nematodes are one of the most powerful biological solutions available, capable of preventing billions in crop losses while supporting soil health and environmental stability.

Advances such as Bionema’s encapsulated formulation technology are unlocking new global potential, making it possible to use these microscopic hunters in countries and climates where traditional formulations have failed.

As agriculture accelerates its shift toward sustainable, biological alternatives, these tiny worms will play an increasingly central role—quietly protecting crops, restoring ecosystems and helping farmers meet the demands of a new regenerative era.

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