Effect of ultraviolet radiation (UVC) on Bemisia tabaci eggs

Abstract

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.