Serpentine Leafminer is a small black and yellow fly that can infest tomato plants. The two commonly known species are Liriomyza sativae and Liriomyza trifolii, and their appearance can differentiate. The larvae of the two species can damage tomato leaves by feeding within the leaf tissue, creating serpentine mines. The mines can cause the leaves to become distorted and reduce the plant’s photosynthetic ability, resulting in yield loss.
Serpentine Leaf Miner management in Tomato
The life cycle of Serpentine Leaf Miner
The Serpentine Leafminer fly has a life cycle of up to 21 days. The adult fly lays its eggs in the leaf epidermis of host plants. The hatching 0f eggs within four days, and the larvae are yellow or green, going through three instars before pupating—the transformation of the pupa into an adult fly, a gray insect with black and yellow spots.
Factors favoring population increase in Serpentine Leaf Miner in the field
- Warm weather conditions are favorable for the multiplication of Serpentine Leafminer flies.
- The higher temperatures and humidity levels can lead to faster development and increased population levels of the insects.
Identification of Serpentine Leaf Miner in Tomato field
Serpentine Leafminer can be identified in a tomato field by its different stages of development.
- Eggs: The eggs are small and orange-yellow. They hatch within four days.
- Larva: The apodous maggot feeds on the chlorophyll, mining between the epidermal layers. When fully grown, the larva measures 3 mm in length. The larval stage lasts about seven days.
- Pupa: Pupation occurs in the soil or on the leaves and takes place inside a thin, loose mesh of silken cocoon. The pupal stage lasts about seven days.
- Adult: The adult is a pale yellowish fly that measures 1.5 mm in length. The female fly punctures the upper surface of the leaf to lay eggs singly. The total life cycle takes about three weeks.
Damage symptoms of Serpentine Leaf Miner in Tomato field
- Leaves with serpentine mines: The larvae create slender, white, winding trails on the leaves as they feed.
- Drying and dropping of leaves: In severe cases, the leaves may become heavily mined and have large whitish blotches. This can cause the leaves to drop prematurely, resulting in defoliation.
- Reduced yield and fruit size: If the infestation occurs early in the fruiting period, it can reduce the yield and size of the fruit, as well as expose it to sunburn.
- High numbers: Leafminers are typically a pest of late summer tomatoes and can reach high numbers. Pole tomatoes, which have a long fruiting period, are more vulnerable than other tomato crops.