Effect of Near Ultraviolet Radiation on Varroa Destructor Using Digital Holographic Interferometry

The incessant threat posed by the Varroa destructor mite to bee colonies has spurred extensive research into control strategies. One of these strategies involves ultraviolet radiation, aiming to harness the damaging effects that this type of radiation induces in arthropods. This study focuses on investigating the potential influence of near ultraviolet (UVA) radiation on the surface damage incurred by Varroa destructor. To address this inquiry, multiple specimens were continuously irradiated with UVA while digital holograms were recorded. To assess surface damage, these holographic records were processed and analyzed. It was found that exposure to radiation induces subtle swelling, around a few tenths of micrometers, which is more pronounced around the anal shield and genital shield of the mite. These alterations could impact the health and viability of this parasitic mite. This is the first time that the measurement and quantification of this superficial damage is reported, contributing to the understanding of the impact of UVA irradiation on the external structure of the mite.