What does a cucumber leaf infected with spider mite look like in a greenhouse? - briefly
A cucumber leaf infested by spider mites in a greenhouse shows tiny yellow‑white stipples and a fine webbing, giving the foliage a bronzed, mottled appearance. Damage typically starts at the leaf margins, causing a silvery stippled look, leaf curling, and early leaf drop.
What does a cucumber leaf infected with spider mite look like in a greenhouse? - in detail
A cucumber leaf that has been attacked by spider mites inside a greenhouse shows a series of characteristic symptoms. The upper surface of the leaf is dotted with tiny, pale‑green or yellowish spots where the mites have removed cell contents. These stipples often coalesce into larger, irregularly shaped patches, giving the leaf a mottled appearance. As feeding continues, the affected tissue turns bronze‑brown and may develop a bronzed sheen.
The leaf margin frequently curls upward or inward, creating a distorted shape that reduces the leaf’s photosynthetic area. Fine, silvery webbing may be visible on the underside of the leaf, especially in dense infestations; the web is most evident along the veins and at leaf junctions. In severe cases, the leaf becomes thin, translucent, and may develop necrotic spots that later dry and crumble.
Typical patterns observed in greenhouse conditions include:
- Concentration of damage on the lower canopy, where humidity is higher and air circulation is poorer.
- Rapid spread to adjacent leaves, often following the same vein network.
- Presence of numerous tiny moving specks (the mites) when the leaf is examined closely with a hand lens.
- Early yellowing of younger leaves, while older leaves retain more of their green coloration.
These visual cues together confirm the presence of spider mite infestation on cucumber foliage in a controlled environment.