Bava Roberto, Palma Ernesto, Bulotta Rosa Maria, Ruga Stefano, Liguori Giovanna, Lombardi Renato, Lupia Carmine, Marrelli Mariangela, Statti Giancarlo, Musella Vincenzo, Britti Domenico, Castagna Fabio
Department of Health Sciences, University of Catanzaro Magna Græcia, 88100 Catanzaro, Italy.
Local Health Autorithy (ASL) Foggia, 71121 Foggia, Italy.
Vet Sci. 2025 Mar 2;12(3):224. doi: 10.3390/vetsci12030224.
is an ectoparasitic mite that causes a true syndrome with complex symptoms in honeybees. For mite control, several synthetic active principles are commercially available. However, these formulations are proving less effective due to the acquisition of resistance mechanisms by the parasite. Naturally derived compounds, such as essential oils, are less prone to generating resistance mechanisms in mite populations and have been proven effective in numerous independent laboratory investigations. In this study, semi-field and field tests were conducted to evaluate the acaricidal efficacy of two essential oils ( and ), which, in our previous residual contact toxicity tests, showed efficacy against mites. For semi-field cage tests, two-level cages were set up. Filter paper soaked with different concentrations of essential oils was placed in the lower compartment of the cage; 20 honeybees and 10 mites were allocated in the upper level. Mite detachment from the honeybees was evaluated after 24 and 48 h. For field tests, cardboard strips soaked with solutions of essential oils at different concentrations were inserted in the experimental hives. Weekly, the strips were replaced, and the fall of parasites on the diagnostic bottom board was assessed. Semi-field tests showed that the essential oils, at the concentrations used, were not toxic to bees. In the semi-field tests, an average acaricidal efficacy of 33% and 60% was obtained, at the highest concentration used, for bergamot and lemon essential oils, respectively. During the 4 weeks of exposure to 600 mL of BEO, the average mite mortality was 28.5%. In the experimental group treated with the intermediate concentration of 1200 mL, the average mite mortality at the end of four weeks was 30.2%, while with the highest concentration of 1800 mL, it was 40.3%. During the four weeks of exposure to 600 mL of LEO, the average mite mortality was 34.1%. In the experimental group treated with the 1200 mL concentration, the average mite mortality at the end of the four weeks was 46.6%, while with the highest concentration, it was 50.7%. This study shows that the acaricidal efficacy observed in field tests differs from that in laboratory tests. Innovative formulations are needed that allow the time-controlled and gradual release of essential oil in the field.
是一种外寄生螨，会在蜜蜂身上引发具有复杂症状的真实综合征。为了控制螨虫，有几种合成活性成分在商业上可用。然而，由于寄生虫获得了抗性机制，这些制剂的效果越来越差。天然衍生的化合物，如精油，在螨虫种群中较不容易产生抗性机制，并且在众多独立的实验室研究中已被证明是有效的。在本研究中，进行了半田间和田间试验，以评估两种精油（和）的杀螨效果，在我们之前的残留接触毒性试验中，这两种精油对螨虫显示出效果。对于半田间笼试验，设置了两级笼子。将浸泡有不同浓度精油的滤纸放在笼子的下层；在上层放置20只蜜蜂和10只螨虫。在24小时和48小时后评估螨虫从蜜蜂身上脱落的情况。对于田间试验，将浸泡有不同浓度精油溶液的纸板条插入实验蜂箱中。每周更换纸板条，并评估诊断底板上寄生虫的掉落情况。半田间试验表明，在所使用的浓度下，精油对蜜蜂无毒。在半田间试验中，在所使用的最高浓度下，佛手柑精油和柠檬精油的平均杀螨效果分别为33%和60%。在暴露于600毫升佛手柑精油的4周期间，螨虫的平均死亡率为28.5%。在接受1200毫升中间浓度处理的实验组中，四周结束时螨虫的平均死亡率为30.2%，而在最高浓度1800毫升时，为40.3%。在暴露于600毫升柠檬精油的四周期间，螨虫的平均死亡率为34.1%。在接受1200毫升浓度处理的实验组中，四周结束时螨虫的平均死亡率为46.6%，而在最高浓度时，为50.7%。本研究表明，田间试验中观察到的杀螨效果与实验室试验不同。需要创新的制剂，以便在田间实现精油的时间控制和逐步释放。
