Aphidius colemani

Overview

Aphidius colemani is one of the most widely used parasitoid wasps for aphid control in protected crops. It is particularly effective against smaller aphid species and forms the foundation of many preventative and early curative aphid management programmes.

The wasp lays eggs inside aphids, eventually producing characteristic aphid mummies that indicate successful establishment.

Type

Parasitoid wasp.

Target Pests

Primary Targets

Melon aphid (Aphis gossypii)
Cotton aphid
Small aphid species

Secondary Targets

Various other susceptible aphids

Identification

Adults are small dark parasitoid wasps.

Parasitised aphids become swollen and bronze-coloured before turning into characteristic mummies.

Adult wasps emerge through a circular exit hole.

Why Aphidius is Important

Aphids reproduce rapidly and can quickly overwhelm crops.

Aphidius provides continuous pressure on aphid populations and is particularly valuable when introduced before colonies become widespread.

Environmental Preferences

Temperature

Optimal:

18–28°C

Reduced activity:

Below 15°C

Light

Good light levels improve host searching behaviour.

Crop Stability

Stable greenhouse environments support population build-up.

Crops Commonly Used In

Cucumbers
Peppers
Chillies
Herbs
Ornamentals

Strengths

Excellent aphid specialist
Easy monitoring through mummy formation
Strong searching behaviour
Good preventative potential
Compatible with predator programmes

Limitations

Species-specific performance
Less effective against some larger aphids
Sensitive to pesticide residues
Requires host aphids for reproduction

Works Well With

Aphidius ervi
Adalia bipunctata
Chrysoperla carnea
Aphid monitoring programmes

Monitoring Establishment

Successful establishment can often be confirmed by:

Aphid mummies
Circular emergence holes
Reduced colony growth
Reduced winged aphid production
Increasing parasitism levels

Inspect growing points and aphid hotspots weekly.

Common Questions

How do I know Aphidius is working?

Look for bronze-coloured aphid mummies and emergence holes.

How quickly does Aphidius work?

Parasitism may become visible within one to three weeks depending on crop conditions.

Can Aphidius eliminate aphids completely?

Usually it suppresses populations rather than eliminating every aphid.

Can it be used preventatively?

Yes. Early introductions are often highly effective.

Common Mistakes

Introducing too late

Large established colonies are harder to suppress.

Wrong aphid species

Different aphid species vary in suitability.

Incompatible pesticides

Many residues reduce parasitoid survival.

Insufficient monitoring

Growers may miss early colony development.

Practical Crop Examples

Cucumbers

Frequently introduced early as part of preventative aphid programmes.

Peppers

Often combined with predators for long-term aphid suppression.

Ornamentals

Useful where repeated aphid pressure occurs throughout the season.