Whitefly Collection and Specimen Preparation

Aleyrodids are found on the aerial parts of a wide range of terrestrial plants. They often inhabit
the underside of leaves, but sometimes can be found on the upper leaf surface. Whiteflies have
six life stages: egg, crawler (1st instar), two sessile nymphal instars (2nd and 3rd instars), the pupa
(4th instar) and adult. Identification of aleyrodids is largely based upon characters found in the
pupal (4th instar) stage.

Collecting Whiteflies
A hand-lens is useful when searching for and collecting whiteflies in the field.  Collect leaves
infested with whiteflies, wrap them in a paper towel to avoid excess humidity and subsequent
fungal growth, place the sample in a zip-lock plastic bag, maintain the sample refrigerated or in a
cooler until it is ready for slide-mounting. Identify the host plant or collect a sample of the plant
sufficient for identification by an expert.

In the Laboratory
Examine the infested leaves under the microscope and select the largest nymphs for specimen
preparation. Place a few drops of 10% potassium hydroxide (KOH) in a small vial. Scrape off
several of the largest nymphs from the leaf surface and place them into the vial. Sometimes it is
helpful to place a drop of KOH on the whitefly pupa to help loosen it from the leaf surface.
Allow them to soak in KOH overnight. The process can be expedited by heating the specimens
on low-heat on a hot plate for 10-20 minutes; however, the specimens are more likely to be
damaged, especially if all of the KOH evaporates, and the specimens are left on the hot plate.

Slide Mounting in Canada Balsam

                       Aleyrodidae                                 USA: Florida
                           Aleyrodinae                                 Gainesville
                                                                              24 VII 2002
                           Bemisia                                      G. A. Evans
                             tabaci                                       Hibiscus
                            (Genn.)                                         rosa-sinensis
                        #2002-340                                    #2002-340