Trialeurodes abutiloneus
The banded-winged whitefly (BWW) is relatively new to the PNW. It has been detected near the gorge in eastern Oregon, and a cloud of whiteflies with bands on their wings. BWW was reported near the same area of the gorge on the Washington side.
Pest description and damage The banded-winged whitefly is a native of North, Central, and South America. The nymphs are similar in appearance to the greenhouse whitefly (GHW), but the adults and eggs are strikingly different. Adult BWW have two jagged bands across their wings; GHW does not. The cream-colored-to-yellow eggs of BWW are laid singly or in small groups with the peduncle inserted into the leaf so they lay parallel to the leaf surface; while the gray to black GHW eggs are laid in partial to full circles standing on end. The pupal case of BWW has a dark marking that is absent in greenhouse whitefly nymph. BWW feed on many herbaceous garden plants and weeds as do the greenhouse whitefly. Known host plants include 33 families of herbaceous ornamentals, weeds and the occasional shrub, with a preference for Malvaceae and Solanaceae. There are three kinds of BWW damage: 1) wilting, chlorotic spotting, leaf drop and dieback of heavily infested twigs; 2) copious honeydew and accompanying sooty mold that builds up and blocks photosynthesis; and 3) the transmission of viruses like abutilon yellows virus, diodia vein chlorosis virus, sweet potato chlorotic stunt virus and tomato chlorosis virus. Plants may look sickly due to removal of sap through whitefly feeding.
Biology and life cycle BWW reproduces about as quickly as GHW. Eggs will hatch in about twelve days in greenhouse temperatures in April. The time to complete a generation is less at higher temperatures, so populations can increase quickly. Many BWW overwinter as adults, but often all stages will be present through the winter.
Pest scouting Watch for honeydew, cast skins or adults caught in yellow sticky traps to develop an aesthetic or tolerance or economic threshold and management. Use pre- and post-treatment numbers to evaluate the effectiveness of management actions. Check traps for signs of parasitoids and withhold all but drastic sprays to give natural enemies a chance to build up.
Management—cultural and physical control
Hose off adult whiteflies with water and use yellow sticky cards to reduce numbers.
Management—biological control
The following predators and parasitoids are known to attack this pest in its native states: a wasp parasite Eretmocerus staufferi, an entomopathogenic fungus Orthomyces aleyrodes, the predatory bug Orius insidiosus, and a variety of coccinellid beetles. Other species/biotypes of Eretmocerus and Orius spp. are available, but their efficacy against T. abutiloneus is unclear.
For biology, life history, monitoring and management
See “Whitefly” in:
Management—chemical control
See “Whitefly” in Table 1:
Chemical Control of Landscape Pests
For further information:
UC IPM Statewide Integrated Pest Management Program. 2016. Identifying Whiteflies. http://www.ipm.ucdavis.edu/PMG/C783/m783bpwhitefly.html