Substantial percentage of world food production depends on pollinating service of honeybees that directly depends on their health status. Among other factors, the success of bee colonies depends on health of developed larvae. The crucial phase of larval development is the first 6 days after hatching when a worker larva grows exponentially and larvae are potentially exposed to xenobiotics via diet. In the present study, we determined the lethal concentration LC (72 h) following single dietary exposure of honeybee larvae to formetanate under laboratory conditions, being also the first report available in scientific literature. Activities of antioxidant enzymes, superoxide dismutase (SOD), catalase (CAT) and glutathione-S-transferase (GST) were also measured in the homogenates of in vitro reared honeybee larvae after single formetanate exposure. Decreased specific activity of SOD and increased activities of CAT and GST suggest the induction of oxidative stress. Higher levels of thiobarbituric reactive species in all samples supported this fact. Comparing determined larval toxicity (LC of 206.01 mg a.i./kg diet) with adult toxicity data, we can suppose that the larvae may be less sensitive to formetanate than the adult bees.

Honey bee, Apis mellifera L., is considered as an essential organism to the agricultural sector due to its role in pollination and alleviation of poverty in rural areas. Many pests attack honey bee colonies causing severe damages and economic losses. These pests include Varroa mites, Vespa hornets, wax moths, small hive beetles, and parasitic flies. Using chemical methods to control these pests causes some negative effects on honey bees and contaminates their products, while using biological control agents is promising and has no serious hazards. This article aimed to review available studies on the role of biological control agents mainly predators, parasitoids, and pathogens in controlling bee's pests and to present new perspectives. Also, obstacles of using biocontrol agents inside and outside the hives were presented. This article is essential for planning integrated management programs for honey bee pests.

Various treatments are currently available for the control of Varroa mites. Some of these treatments depend on using natural and nonchemical compounds. In this study, the impacts of some materials (oxalic acid, thymol, and potassium citrate) on the survival of honey bees and some quality parameters were investigated under laboratory conditions. The potential impacts of different feeding types (sugar syrup, sugar candy, honey candy, honey jelly, and creamed honey) mixed with the tested Varroa control materials on honey bees were also studied. The study showed that using high percentages of oxalic, thymol, or potassium citrate can passively impact honey bees while using 0.5% is more preferable. The study also proved that feeding type, either as a liquid or solid, except for honey jelly, has no undesirable impacts on the survival or studied parameters of honey bee workers and drones. Drones fed on potassium regardless of feeding type were able to survive significantly at day 4 more so than drones fed on oxalic acid or thymol. Investigations into the role of potassium in enhancing the survival of bee drones and in controlling Varroa mites are recommended.

No abstract