Whiteflies

There are several species of whitefly that are key pests in ornamental production. The most recent introduction in the PNW is the Q biotype whitefly which has resistance or reduced susceptibility to many insecticides. For more information on the new strain of whitefly, see the fact sheet at the link. The best site for current information and updates on Q biotype whitefly is the website developed by the Technical Advisory Committee.

Management:
Below you will find some information and links on the management of whiteflies.

Biological control (taken from the PNW Insect Management Handbook - Greenhouse Section last revised 2013)

1. ladybird beetle (Delphastus pusillus)

2. parasitic wasps (Encarsia formosa ; (Eretmocerus mundis)— Encarsia has been very successful in some greenhouses

3. pathogenic fungi (Beauveria bassiani ; Paecilomyces fumosoroseus)

Chemical control (taken from the PNW Insect Management Handbook - Greenhouse Section last revised 2012).

In all cases, follow the instructions on the pesticide label. The PNW Insect Management Handbook has no legal status, whereas the pesticide label is a legal document. Read the product label before making any pesticide applications.

Direct control efforts at larvae feeding on lower leaf surfaces.

Links

ATTRA Greenhouse IPM: Sustainable whitefly control This site covers the basics in easily written language and has a strong emphasis on integrated management including good sections on biological control and the use of biorational materials and insect growth regulators.

USDA Whitefly Knowledgebase. This website has good information on the following species of whiteflies: bandedwing whitefly, greenhouse whitefly, silverleaf whitefly, and sweet potato whitefly; and a key to distinguish the above given various life stages. The management section covers many useful basics.

A Grower’s Guide to Using Biological Control for Silverleaf Whitefly on Poinsettias in the Northeast United States is a website designed by the University of Massachusetts Extension Service. It has extensive information on whitefly biology, biological control.

UC IPM Pestnotes website on whifeflies has one of the larger lists of the various whitefly species acting in ornamentals

Adult whiteflies on the underside of a blueberry leaf

Adult greenhouse whitefly

Greenhouse whitefly eggs



Greehouse whitely larva with distinctive long setae (hairs)

Bemisia whitefly larva with less noticeable, shorter ring of setae

Page last modified 4/12/13