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Bemisia tabaci, the silverleaf whitefly, is a serious pest, and vector for disease, in many agricultural crops. The current common control strategy for this pest is applications of chemical synthetic insecticides. Resistance to several insecticides has already been observed in this species. If non-chemical control options were available, their use could reduce the reliance of insecticides and help slow insecticide resistance in this whitefly. Ultraviolet (UV) radiation is nonvisible radiation with wavelengths ranging from 100 nm to 400 nm. UVC, wavelengths 100 nm to 280 nm, has been found to have insecticidal properties. UVC radiation of wavelength 254 was tested on B. tabaci eggs at 2 different distances, 49.5 cm and 30.5 cm, and at 4 different times, 15 (s), 30 (s), 60 (s), and 90 (s) per distance to see what effect they had on the eggs of B. tabaci. All UVC applications tested had a significant reduction in hatching when compared to the control based on an analysis of variance (One-way ANOVA) and pos-hoc Tukey HSD test. LD50, LD90, and LD95 were calculated. At 49.5 cm irradiation times were found to be, LD50 = 31.8 (s), LD90 = 86.9 (s), and LD95 = 80.5 (s). For the 30.5 cm distance irradiation times were, LD50 = 19.2 (s), LD90 = 63.1 (s), and LD95 = 75.5 (s). This study shows that UVC might be a viable non-chemical control option for controlling B. tabaci.

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The grape mealybug, Pseudococcus maritimus (Ehrhorn; Hemiptera: Pseudococcidae), is the primary vector of Grapevine Leafroll associated Viruses (GLRaVs) in Washington State vineyards. Rearing laboratory colonies of grape mealybug has proven difficult. Several host plants were tested to determine their suitability for use as an alternate host plants for laboratory colonies of grape mealybug. Of the plants tested, colonies of grape mealybug were successful on pumpkin (Cucurbita pepo cv 'Connecticut field') leaves and vines. Mealybugs were able to develop from the crawler stage, through developmental instars, and adults were able to reproduce viable offspring. To date this is the only successful study to raise grape mealybugs on a cucurbit. Pumpkin appears to be a viable alternate host plant for laboratory colonies of the grape mealybug.