PHYSIOLOGICAL ECOLOGY The Effect of Ultraviolet-A Radiation Exposure on the Reproductive Ability, Longevity, and Development of the Dialeurodes citri (Homoptera: Aleyrodidae) F1 Generation KALEEM TARIQ, 1,2 MAH NOOR, 3 SHAFQAT SAEED, 4 AND HONGYU ZHANG 1,2,5 The authors report no conflicts of interest regarding this work. Environ. Entomol. 44(6): 1614–1618 (2015); DOI: 10.1093/ee/nvv133 ABSTRACT Ultraviolet (UV) light has been used worldwide to monitor and trap insect pests. Whitefly adults show conspicuous positive phototactic behavior toward UV light stimuli; however, knowledge of the effect of UV light exposure on various life-history parameters of Dialeurodes citri remains limited. The present research aimed to investigate the effect of ultraviolet radiation (UV-A; long-wave) exposure on the reproduction and longevity of D. citri adults as well as the development of immature (eggs, larvae, and pupae) flies in the F1 generation. Paired D. citri adults were exposed to UV-A radiation for different periods (0, 1, 4, and 7 h/d) until the end of their life. The results of the experiment revealed that fecundity and oviposition rates increased when adults were irradiated for 1 and 4 h/d, but interestingly, both were significantly decreased compared with those of the controls after the longest exposure time (7 h/d). The longevity of adults of both sexes and the cumulative survival of F1 immatures were decreased with in- creased exposure time. Exposure to UV-A radiation prolonged the developmental time of immature stages, and a positive correlation was observed with exposure time. Exposure to UV light significantly in- hibited egg hatching, larval development, pupation, and adult emergence. To the best of our knowledge, this is the first study describing the effect of UV radiation on a homopteran insect pest. This research may provide a foundation for the scientific community to use UV light in the field as an integrated pest management strategy to control this devastating agricultural pest. KEY WORDS Dialeurodes citri, UV-A radiation, reproduction, longevity Owing to global climate change, the intensity of ultravi- olet (UV) radiation on the surface of Earth has in- creased since 1979 (Williamson et al. 1996, Herman 2010, Manney et al. 2011, Anderson et al. 2012), and this increase in intensity has promoted a surge of re- search into the effects of UV radiation on living organ- isms. UV radiation causes stress to many living organisms (Meyer-Rochow 2000, Schauen et al. 2007). It penetrates cells, causing photo-excited states of cellu- lar photosensitizers and ultimately generating reactive oxygen species that damage nucleic acids, membrane lipids, and proteins (Jurkiewicz and Buettner 1994, Vile and Tyrrell 1995). UV results in different types of cell damage, such as mutations, alterations in cell signal- ing pathways, and cytotoxicity, which have signifi- cant effects on various biological processes (McMillan et al. 2008). Effects of UV radiation on different in- sect biological processes, such as developmental physi- ology (Gunn 1998), biochemistry (Meng et al. 2009, 2010), and behavior (Leech and Johnsen 2003, Cowan and Gries 2009), have also been reported. Furthermore, UV radiation causes oxidative stress and photoreceptor damage in insects (Meyer-Rochow and Mishra 2007, Lopez-Martinez et al. 2008, Meng et al. 2009). The citrus whitefly Dialeurodes citri (Ashmead; Homoptera: Aleyrodidae) is a destructive pest of citrus orchards in China. This pest originated in Southeast Asia and is also found in other regions of the world such as Europe, Russia, the Mediterranean Basin, and North and South America (Mound and Halsey 1978, Nguyen et al. 1993, Argov et al. 1999). D. citri causes serious damage to citrus plants by sucking their phloem sap and ultimately causing sooty mold that impairs fruit production (Argov et al. 1999). Thirty different families of this insect have been reported worldwide (Bellows and Meisenbacher 2007). Different chemical insecti- cides have been used against D. citri, with the insect becoming resistant to many of them (Yigit et al. 2003), thus complicating the control of D. citri through chem- ical insecticides. 1 State Key Laboratory of Agricultural Microbiology, Institute of Urban and Horticultural Pests, Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China. 2 Hubei Collaborative Innovation Center for the Characteristic Resources Exploitation of Dabie Mountains, China. 3 National Key Laboratory of Agromicrobiology, Huazhong Agricul- tural University, Wuhan, Hubei 430070, China; The Key Laboratory of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei 430070, China. 4 Department of Entomology, Faculty of Agricultural Sciences and Technology, Bahauddin Zakariya University, Bosan Road, Multan 60000, Pakistan. 5 Corresponding author, e-mail: hongyu.zhang@mail.hzau.edu.cn. 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