Queen-produced volatiles change dynamically during reproductive swarming and are associated with changes in honey bee (Apis mellifera) worker behavior

Abstract

-During colony fission, honey bee workers are exquisitely sensitive to the presence of their queen in airborne swarms and bivouacs and will abandon swarming if she is absent. However, it is not known whether swarming queens produce a chemical bouquet that is distinct from non-swarming queens, containing either unique chemicals or altered proportions of chemicals. We found that queens emitted higher quantities and greater numbers of unique volatiles at liftoff than they did prior to swarming or in clustered bivouacs, and swarming workers tended to be attracted to these liftoff volatile blends. Pentadecane and heptadecane were collected most frequently and emitted in significantly higher quantities by queens at liftoff; these compounds have been described as pheromone components in other social insects, but not yet in honey bees. Our results suggest that volatile emission by queens is more dynamic than previously thought and that changes in their chemical signals may play a role in regulating the behavior of swarming workers.honey bees / chemical ecology / pheromones / worker behavior / swarming

Thrips as the Transmission Bottleneck for Mixed Infection of Two Orthotospoviruses

“…Data were analyzed by Agilent's enhanced data analysis software, and compounds were found by chromatogram deconvolution. In order to evaluate whether the plant volatile blends changed with virus infection, we removed common containments and selected volatile compounds that were produced at least twice within any one of the treatments as "candidate compounds" [69]. This selection gave us a manageable number of volatile compounds (42).…”

Volatiles from Different Instars of Honeybee Worker Larvae and Their Food

“…Pentadecane has been reported as a larval volatile [26]. It was detected in nurse bees [27] and queens at liftoff [28], coupled with heptadecane. Octadecane is found in comb wax, with worker bees treated with this compound becoming less acceptable to their untreated nestmates [29].…”

“…( E )-Geranylacetone has been previously identified as a queen volatile [28], a male-produced sex pheromone of cerambycid beetle ( Hedypathes betulinus ) [35] and a male-produced aggregation pheromone of the brown spruce longhorn beetle ( Tetropium fuscum ) [36]. Concentrations of this compound in larvae did not show obvious changes with the growth of individual larvae, and the concentrations only displayed a dramatic increase during the capping stage (the 5th instar).…”

Does nonreproductive swarming adapt to pathogens?

“…Honey bee swarming, also termed reproductive swarming, is a natural division of the hive population and colony fission; when the number of workers exceeds the capacity of the hive, the old queen will travel to a new location with approximately three-fourths of the colony’s worker bees and drones. Generally, this swarming occurs between 10 AM and 2 PM on a warm sunny day in the spring or summer, seasons with sufficient plant nectar and temperate climate to facilitate the development and growth of the new colony [ 7 ]. Due to rapid growth, reproductive swarming is also useful for increasing the population and maintaining a high level of reproduction during times of rich food resources, and it is the major way of reproduction of honey bee colonies [ 8 ].…”

“…One of the most effective mechanisms by which honey bees can protect themselves against pathogens or parasites is by changing their behavior [ 11 ]. Honey bees are a social insect, and they rely mainly on behavioral and physiological defenses against diseases [ 7 ]. Although habitat loss [ 12 ] and pesticides [ 13 ] have been confirmed to impair honey bee health, pathogens are considered the most serious threat [ 14 ].…”