Whitefly
/ˈwaɪtˌflaɪ/
Definition
Whitefly refers to several tiny sap-feeding insect pests related to aphids and scale insects. Adults are moth-like, with white, waxy wings, and they usually gather on leaf undersides. Immature stages stay attached to the plant and feed by piercing tissue and sucking sap. Infestations can cause yellowing, sticky honeydew, sooty mold growth, and weakened plant growth, especially on houseplants, vegetables, and greenhouse crops.
Effects on Plants
- Sap loss and leaf decline: By feeding on phloem, the sugar-rich transport tissue, whitefly weakens plants and can cause yellowing, curling, wilting, and early leaf drop, especially on tender new growth.
- Honeydew and sooty mold: Whitefly leaves sticky honeydew on foliage. This coating supports sooty mold, which blocks light and reduces photosynthesis, the process plants use to make sugars from light.
- Virus spread in crops: Some species transmit plant viruses, especially in vegetables and ornamentals. Damage can continue even after feeding stops because infection affects new growth and overall vigor.