Sedat Sevin
Vijayakumar Bommuraj
Yaira Chen
Ohad Afik
Shlomi Zarchin
Shimon Barel
Okan Can Arslan
Babür Erdem
Hidayet Tutun
Jakob A Shimshoni
Background: Varroa control is essential for the maintenance of healthy honey bee colonies. Overuse of acaricides has led to the evolution of resistance to those substances. Studies of the short-term acaricidal effects and safety of various lithium salts have recently been reported. This study examined the long-term in vitro and in vivo bee toxicities, short-term motor toxicity to bees, and long-term anti-Varroa field efficacy of several lithium salts.
Results: In an in vitro chronic-toxicity assay, lithium citrate (18.8 mM) was the most toxic of the examined salts, followed by lithium lactate (29.5 mM), and lithium formate (32.5 mM). In terms of acute locomotor toxicity to bees, all of the lithium salts were well tolerated and none of the treatment groups differed from the negative control group. In an in vitro survival study, all of the lithium treatments significantly reduced bee life spans by a factor of 1.8-7.2, as compared to the control. In terms of life expectancy, lithium citrate was the most toxic salt, with no significant differences noted between lithium formate and lithium lactate. In the bee-mortality field study, none of the examined treatments differed from the negative control. Amitraz and lithium formate exhibited similar acaricide effects, which were significantly different from those observed for lithium lactate and the negative control CONCLUSION: In light of lithium formate's honey bee safety and efficacy as an acaricide, additional sublethal toxicity studies in brood, drones, and queens, as well as tests aimed at the optimization of administration frequency are warranted. This article is protected by copyright. All rights reserved.
Sedat Sevin
Vijayakumar Bommuraj
Yaira Chen
Ohad Afik
Shlomi Zarchin
Shimon Barel
Okan Can Arslan
Babür Erdem
Hidayet Tutun
Jakob A Shimshoni
Background: Varroa control is essential for the maintenance of healthy honey bee colonies. Overuse of acaricides has led to the evolution of resistance to those substances. Studies of the short-term acaricidal effects and safety of various lithium salts have recently been reported. This study examined the long-term in vitro and in vivo bee toxicities, short-term motor toxicity to bees, and long-term anti-Varroa field efficacy of several lithium salts.
Results: In an in vitro chronic-toxicity assay, lithium citrate (18.8 mM) was the most toxic of the examined salts, followed by lithium lactate (29.5 mM), and lithium formate (32.5 mM). In terms of acute locomotor toxicity to bees, all of the lithium salts were well tolerated and none of the treatment groups differed from the negative control group. In an in vitro survival study, all of the lithium treatments significantly reduced bee life spans by a factor of 1.8-7.2, as compared to the control. In terms of life expectancy, lithium citrate was the most toxic salt, with no significant differences noted between lithium formate and lithium lactate. In the bee-mortality field study, none of the examined treatments differed from the negative control. Amitraz and lithium formate exhibited similar acaricide effects, which were significantly different from those observed for lithium lactate and the negative control CONCLUSION: In light of lithium formate's honey bee safety and efficacy as an acaricide, additional sublethal toxicity studies in brood, drones, and queens, as well as tests aimed at the optimization of administration frequency are warranted. This article is protected by copyright. All rights reserved.