Biological impact of ultraviolet-B radiation on spider mites and its application in integrated pest management

Many plant-dwelling mites reside on lower leaf surfaces. The biological impact of solar ultraviolet-B (UV-B) radiation on spider mites has been demonstrated over the last decade. Due to the serious problem of acaricide resistance in spider mites, the development of alternative control methods and establishment of an integrated pest management (IPM) strategy are urgently needed, especially for greenhouse horticultural crops such as strawberries. A physical control method for spider mites using UV-B lamps (UV-B method) has been established. Using the UV-B method, simultaneous control of spider mites and powdery mildew, a major disease, is possible, making it is a favorable IPM strategy. Here, I introduce general findings regarding the biological impact of UV radiation on spider mites and phytoseiid mites, useful natural enemies for biological control, over the last decade, including dose response, effective wavelengths, and photoreactivation. Moreover, I introduce the application of UV-B to spider mite control in strawberry greenhouses, including the possibility of concurrent use with biological control via phytoseiid mites, and discuss its possible contributions to IPM.