Laboratory populations of the sweet potato whitefly, Bemisia tabaci, have been shown to consist of both migratory and trivial flying morphs. The behavior of these forms as part of the process of short-range migration was examined under field conditions. Insects were marked in a field of melons using fluorescent dust during two consecutive growing seasons. During the first growing season, passive traps used to collect living whiteflies, were placed along 16 equally spaced transects radiating from the field to a distance of up to 1.0 km. Wind out of the north-east consistently carried migrating whiteflies to traps placed along transects in the south-western quadrant because cold air drainages dictate wind direction during early morning hours in the desert South-west. For this reason, during the second season traps were laid out over fallow ground in a rectangular grid extending 2.7 km to the south-west of the marked field. If dispersal was entirely passive, patterns could be described using a diffusion model. Statistical examination of the data, howèver, demonstrated that the distribution on all days was patchy. Geostatistical techniques were used to describe the observed patchiness. Traps in the immediate vicinity of the marked field caught more whiteflies than the daily median. Large numbers were also collected from near the periphery of the grid. White-flies were far less prevalent in the grid's center. As a result, the distribution of captured whiteflies can be described as bimodal. These patterns confirm behavior observed in the laboratory, i.e., a portion of the population are trivial fliers that do not engage in migration and are consequently captured in traps near the field, and a portion initially respond to cues associated with skylight, ignoring cues provided by the ground, and fly for a period of time before landing in distant traps. During both years movement out of the field had an exaggerated directional component on 13 of 14 days.

Susceptibility of males and females of the Liriomyza leafminer parasitoid Diglyphus begini (Ashmead) to methomyl, oxamyl, fenvalerate, and permethrin was compared with laboratory bioassays. For each insecticide and five populations tested, males were more susceptible than females. Differences in LCsos between the sexes ranged from 1.3-to 15.7-fold and were greater in resistant compared with susceptible populations. Tibia length was significantly less for male than female D. begini. Size differences ranged from 1.1-to 1.2-fold. Piperonyl butoxide synergized oxamyl and fenvalerate in males and females, suggesting that oxidative detoxification was important in both sexes. The addition of piperonyl butoxide to oxamyl affected both sexes similarly. The synergistic effect of piperonyl butoxide with fenvalerate was significantly greater for females than males, suggesting greater oxidative detoxification of fenvalerate in females than males. KEY WORDS Insecta, biological control, pesticide resistance, synergism THE LEAFMINERS Liriomyza trifolii (Burgess) and L. sativae Blanchard (Diptera: Agromyzidae) are important pests of vegetable and ornamental crops throughout the world (Minkenberg & van Lenteren 1986, Parrella 1987). Diglyphus begini (Ashmead) (Hymenoptera: Eulophidae), an externallarval parasitoid of Liriomyza spp., shows potential for biological control of leafminers in greenhouse and field situations (Parrella et al. 1989). In Hawaii, D. begini has been reared from Liriomyza on beans, watermelon, cucumber, tomato, chrysanthemum, and onion (Mothershead

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Vector surveillance is an essential component of vector-borne disease prevention, but many communities lack resources to support extensive surveillance. The Great Arizona Mosquito Hunt (GAMH) was a collaborative citizen science project conducted during 2015-17 to enhance surveillance for Aedes aegypti in Arizona. Citizen science projects engage the public in scientific research in order to further scientific knowledge while improving community understanding of a specific field of science and the scientific process. Participating schools and youth organizations across the state conducted oviposition trapping for 1-4 wk during peak Ae. aegypti season in Arizona and returned the egg sheets to collaborating entomologists for identification. During the 3-year program, 120 different schools and youth organizations participated. Few participants actually collected Aedes eggs in their traps in 2015 or 2017, but about one-third of participants collected eggs during 2016, including 3 areas that were not previously reported to have Ae. aegypti. While relatively few new areas of Ae. aegypti activity were identified, GAMH was found to be a successful method of engaging citizen scientists. Future citizen science mosquito surveillance projects might be useful to further define the ecology and risk for vector-borne diseases in Arizona.

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