Acaricidal efficacy of ultraviolet-C irradiation of Tetranychus urticae adults and eggs using a pulsed krypton fluoride excimer laser

Parasites & Vectors

Thierry Hance¹  Jérôme Ambroise²  Omar Nyabi²  Jean-Luc Gala²  Sergey Babichenko³  Ott Rebane³ 

[1] Biodiversity Research Centre, Earth and Life Institute, Université catholique de Louvain, Croix du sud 4-5, 1348, Louvain-la-Neuve, Belgium;Centre for Applied Molecular Technologies, Institute of Clinical and Experimental Research, Université catholique de Louvain, Tour Claude Bernard, Avenue Hippocrate 54-55, First floor, B1.54.01, 1200, Brussels, Belgium;LDI Innovation OÜ, Sära 7, Peetri, Estonia;

关键词: Germicidal effect;    Physical control;    Ultraviolet-C;    Pulsed irradiation;    Excimer laser;    Krypton fluoride;    Tetranychus urticae;    Mortality;    Egg hatchability;   

DOI  :  10.1186/s13071-021-05085-7

来源: Springer

【 摘 要 】

BackgroundPulsed ultraviolet (UV)-C light sources, such as excimer lasers, are used in emerging non-thermal food-decontamination methods and also have high potential for use in a wide range of microbial decontamination applications. The acaricidal effect of an experimental UV-C irradiation device was assessed using female adults and eggs of a model organism, the two-spotted spider mite Tetranychus urticae.MethodsUV-C light was generated by a pulsed krypton fluoride excimer laser operating at 248-nm emission wavelength. The pulse energy and pulse repetition rate were 5 mJ and up to 100 Hz, respectively. The distance from the light source to the target was 150 mm; the target surface area was 2.16 cm2. The exposure time for the mites and fresh eggs varied from 1 to 4 min at 5–300 mW, which corresponded to UV doses of 5–80 kJ/m2. Post-irradiation acaricidal effects (mite mortality) were assessed immediately and also measured at 24 h. The effects of UV-C irradiation on the hatchability of eggs were observed daily for up to 12 days post-irradiation.ResultsThe mortality of mites at 5 and 40 kJ/m2 was 26% and 92%, respectively. Mite mortality reached 98% at 80 kJ/m2. The effect of exposure duration on mortality was minimal. The effect of irradiation on egg hatchability was even more significant than that on adult mite mortality, i.e. about 100% egg mortality at an accumulated dose of as little as 5 kJ/m2 for each exposure time.ConclusionsA high rate of mite mortality and lethal egg damage were observed after less than 1 min of exposure to 5 mJ UV-C pulsed irradiation at 60 Hz. Pending further developments (such as beam steering, beam shaping and miniaturisation) and feasibility studies (such as testing with mites in real-life situations), the reported results and characteristics of the UV-C generator (modulation of energy output and adaptability to varying spot sizes) open up the use of this technology for a vast field of acaricidal applications that require long-range radiation.Graphical Abstract

【 授权许可】

CC BY