Tomato fruitworm on tomatoes
In tomatoes this pest goes by tomato fruitworm. Young larvae bore into green fruit about 0.75–2 inches across at the stem end, leaving a watery cavity full of cast skins and frass, and move from fruit to fruit. The eggs sit singly on the leaves, which is where Trichogramma attack them. UC IPM notes that damaging numbers rarely occur before August. UC IPM warns that released parasites are not always effective, so check eggs for parasitism within a few days of each release: parasitised eggs turn black.
At a glance
- Damage
- Ear tips eaten and full of frass; holes in tomato fruit
- Type
- Chewing
- Settings
- Field, Garden
- Threshold
- 3 or more healthy white eggs in a 30-leaf sample triggers a second sample (UC IPM, processing)
- Release
- Trichogramma spp.
- Rate
- At least 100,000 T. pretiosum per acre during the egg-laying period (UC IPM, commercial tomato)
How to confirm it
In corn: pull back the husk at the tip and look for a caterpillar and moist frass among the eaten kernels, usually just one per ear. In tomato: a hole at the stem end of green fruit with a watery, frass-filled cavity. The larva is up to 1½–2 inches (4–5 cm), striped, and green, brown, pink or nearly black, with a rough texture from small spines.
Identification, lifecycle, degree days and every control option are on the full Corn earworm profile. Not sure it is this pest? Answer four questions about the damage.
Work it out
How many do I need?
Carries Trichogramma spp. and tomato through so nothing is re-entered. Open the calculator →