Giant Whitefly

Description: Like other whiteflies, GtWF adults and nymphs damage plants by removing sap through their needle-like mouthparts which are inserted into plant tissue. Heavy infestations usually result in the decline of plants. Regular watering and fertilizing will help to maintain good plant health. Both adults and nymphs also excrete a sticky liquid called honeydew which falls on lower leaves and promotes growth of black sooty mold. Large amounts of white flocculence produced by GtWF nymphs are windblown and create nuisance problems by its sticking to outdoor plants, furniture, and other items.. GtWF infestations have been found on hibiscus, fiddlewood, plumeria, sundrops, hau, avocado, citrus, guava, cinnamon, coconut, and orchid tree. The adult Giant Whitefly (GtWF) measures up to 4 mm (3/16") long and is larger than most whitefly species, hence its name. The eggs are laid in spiral patterns on the undersides of leaves and hatch into an immature stage called nymphs. The nymphs are oval-shaped and produce an abundance of long, white, waxy filamentous material which can cover the leaf and can be observed from afar. The giant whitefly is similar in appearance to the spiraling whitefly, Aleurodicus dispersus Russell, which has been in Hawaii since 1978. Both whiteflies commonly infest hibiscus and plumeria. The GtWF can be distinguished from the spiraling whitefly by its highly patterned wings which are positioned tent-like over its body. The spiraling whitefly has only a few light markings on its wings and are held in a flattened position.

Damage:  Like other whiteflies, GtWF adults and nymphs damage plants by removing sap through their needle-like mouthparts which are inserted into plant tissue. Heavy infestations usually result in the decline of plants. Regular watering and fertilizing will help to maintain good plant health. Both adults and nymphs also excrete a sticky liquid called honeydew which falls on lower leaves and promotes growth of black sooty mold. Large amounts of white flocculence produced by GtWF nymphs are windblown and create nuisance problems by its sticking to outdoor plants, furniture, and other items.

Hosts: GtWF infestations have been found on hibiscus, fiddlewood, plumeria, sundrops, hau, avocado, citrus, guava, cinnamon, coconut, and orchid tree.

• New Pest Advisory
• Plant Pest control activities highlighted in the  Hawaii Department of Agriculture Annual 2006 Report   beginning on page 27.