Leafminer

Overview

Leafminers create mines in leaves and reduce photosynthetic area.

Symptoms

• Serpentine mines in leaves
• Pupae in leaf or substrate
• Reduced vigour

Conditions that increase risk

• Warm conditions
• Continuous cropping

Biological control options

• Parasitoid wasps (e.g., Diglyphus-type programmes)

IPM notes

• Remove heavily mined leaves where practical
• Maintain monitoring

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Further guidance

• Leafminer — Biocontrol Foundations

Key natural enemies

• Diglyphus isaea

Environmental drivers

• Activity increases in mild to warm conditions; repeated generations occur in protected cropping.
• Hot-spots often form where crop is lush and sheltered.
• Reservoir weeds/volunteer plants can sustain populations between crops.