Ana's notes: It is important to differentiate leafmining flies and leafmining caterpillars, since the management of the two groups of pests is different. The leafminers attacking coffee, cotton, groundnut, soybean and citrus are caterpillars, not leafmining flies. Some work was done on neem for control of leafminers on tomatoes some years back, but it was not published. I am looking for it; it should be added when available.
Leafmining flies (Leafminers) Liriomyza spp.
Female flies make numerous small, whitish punctures on the foliage when feeding and depositing eggs. These punctures can serve as entry points for disease-causing organisms such as bacteria and fungi. The eggs hatch into tiny yellow maggots that feed on leaf tissues leaving a wandering track known as mines. Full-grown maggots come out of the mines to pupate in the soil beneath the plants or on the foliage. Maggots are the most destructive stage.
The mines may reduce photosynthetic activity, affecting development of flowers and fruits. In severe infestation, the leaves might be completely mined, dry and fall off prematurely, causing loss of vigour and turgidity of the plant. This may eventually result in wilting, in particular in warm weather, leading to yield loss, fruit sunscald, or in serious cases death of the plant, especially of young pants.
- Control by natural enemies is important.
- Ploughing can help in exposing pupae to desiccation and natural enemies.
- Neem products are effective for controlling leafminers. For more information on neem click here.