Allium Leafminer
Scientific group or name: Phytomyza gymnostoma
Overview
Allium leafminer is a leaf-mining fly whose larvae tunnel through leaves and into stems and bulbs.
Host plants
Leeks, onions, garlic, chives and other Allium species.
Identification
Adult feeding punctures form rows of small pale marks. Larvae are pale maggots, and brown pupae may be found within stems or bulbs.
Damage and symptoms
Mining distorts leaves and weakens plants. Secondary rots can develop in damaged stems and bulbs.
Lifecycle and favourable conditions
There are distinct adult activity periods, and exposed allium crops are at greatest risk during egg laying.
Monitoring
Inspect leaves for lines of feeding punctures and check damaged stems for larvae or pupae.
Management
Use insect-proof mesh before adult activity, rotate crops, remove residues and do not compost heavily infested material unless destruction is assured.
Biological control and natural enemies
No simple commercial biological-control programme is established for all situations. Exclusion and crop hygiene are the principal measures.
Biological control should be selected only after the pest has been identified and the crop, temperature, growing environment and pest pressure have been considered.
Related BioWiki pages
This page provides general integrated pest-management information. Identification and control decisions should be confirmed for the crop and local situation.