What does a spider mite look like on eggplant in a greenhouse? - briefly
Spider mites are minute, pale‑green to yellow arachnids that cluster on the undersides of eggplant leaves, leaving stippled, bronzed spots and a fine silken web. Infested foliage often looks dusty or chalky, with tiny moving specks visible when magnified.
What does a spider mite look like on eggplant in a greenhouse? - in detail
Spider mites on greenhouse‑grown eggplant are extremely small, typically 0.2–0.4 mm in length. Adults are oval to round, with a soft, translucent body that appears pale green, yellow, or light brown when observed with the naked eye. Under magnification, the dorsal surface shows a pattern of fine, overlapping plates (dorsal setae) and minute hairs that give the mite a slightly fuzzy texture.
The most noticeable sign of infestation is stippling on the leaf surface. Tiny, pale spots form a peppered pattern as the mites pierce individual cells and extract sap. As feeding continues, the spots may coalesce into larger yellow or bronze patches, eventually leading to leaf bronzing and premature leaf drop. Fine, silky webbing often appears on the undersides of leaves, at leaf junctions, and along petioles; this web is a reliable indicator of a developing colony.
Key identification points include:
- Size: less than half a millimeter, invisible without a hand lens.
- Color: translucent to pale green/yellow; may appear reddish when engorged after feeding.
- Body shape: oval, slightly flattened, with a pair of front legs longer than the rear legs.
- Legs: four pairs, the first pair adapted for piercing plant tissue.
- Webbing: fine, silken threads, especially on the leaf underside and around leaf axils.
Life‑stage differences are also evident. Eggs are oval, smooth, and laid singly on the lower leaf surface; they are barely visible unless magnified. Nymphs progress through several stages, each slightly larger and darker than the previous, retaining the translucent quality but becoming more opaque as they mature. Adult females may be slightly larger than males and can be distinguished by a more robust abdomen.
In a greenhouse environment, spider mites thrive in warm, dry conditions. Inspect the lower canopy first, as humidity is lower there, and use a 10× hand lens or a digital microscope to confirm the presence of the mites and their webbing. Early detection relies on recognizing the stippled leaf pattern combined with the characteristic fine silk.