How to identify spider mite on a tomato? - briefly
Inspect leaf undersides for fine webbing and tiny, moving specks; feeding damage appears as stippled, yellow‑to‑bronze spots. The mites are minute, pale‑to‑reddish bodies, usually visible only with a magnifying lens.
How to identify spider mite on a tomato? - in detail
Spider mites on tomato plants can be recognized through a combination of visual clues and simple diagnostic tools.
Leaves often display tiny, yellow‑white speckles where the mites have fed. The stippling appears as a fine mosaic, sometimes coalescing into larger pale patches. As infestations progress, the foliage may turn bronze or develop a stippled, bronzed appearance.
The insects themselves are extremely small, measuring 0.2–0.5 mm, and are most visible on the undersurface of leaves. A hand lens or 10× magnifier reveals oval, translucent bodies with four pairs of legs. Adult females typically have a rounded abdomen; males are narrower and more elongated.
Webbing is another reliable indicator. Fine silk threads form a delicate web on leaf edges, between leaf veins, and on the fruit surface. The presence of webbing, especially when combined with stippling, strongly suggests a spider mite problem.
To confirm identification, follow these steps:
- Inspect the lower leaf surface with a magnifying lens; look for moving mites and their characteristic shape.
- Gently tap a leaf over a white sheet of paper; fallen mites will appear as tiny specks.
- Place a sticky trap (yellow or blue) near the plant for 24–48 hours; captured mites can be examined under a microscope.
- Collect a leaf sample, place it in a sealed container, and examine under a low‑power microscope (40–100×) for eggs, larvae, and adult stages.
Environmental conditions that favor outbreaks include hot, dry weather and low humidity. High temperatures accelerate mite reproduction, while dry air reduces natural predator activity. Monitoring temperature and moisture levels can help predict population surges.
When spider mites are detected, immediate action is required to prevent rapid spread. Early intervention includes increasing humidity around the plants, washing foliage with a strong jet of water, and applying miticidal oils or soaps according to label instructions. Regular scouting, at least twice weekly during peak season, ensures infestations are caught before they cause significant leaf loss or fruit damage.