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Simple Summary: The rearing of honeybee larvae in the laboratory is an important tool for studying the effects of plant protection products or pathogens on developing and adult bees, yet how rearing under artificial conditions affects the later social behavior and physiology of the honeybees is mostly unknown. We, here, show that honeybees reared in the laboratory generally had a lower probability for performing nursing or foraging tasks compared to bees reared under natural conditions in bee colonies. Nursing behavior itself appeared normal in in vitro honeybees. In contrast, bees reared in the laboratory foraged for a shorter period in life and performed fewer trips compared to bees reared in colonies. In addition, in vitro honeybees did not display the typical increase in juvenile hormone titer, which goes hand-in-hand with the initiation of foraging in colony-reared bees. In vitro rearing of honeybee larvae is an established method that enables exact control and monitoring of developmental factors and allows controlled application of pesticides or pathogens. However, only a few studies have investigated how the rearing method itself affects the behavior of the resulting adult honeybees. We raised honeybees in vitro according to a standardized protocol: marking the emerging honeybees individually and inserting them into established colonies. Subsequently, we investigated the behavioral performance of nurse bees and foragers and quantified the physiological factors underlying the social organization. Adult honeybees raised in vitro differed from naturally reared honeybees in their probability of performing social tasks. Further, in vitro-reared bees foraged for a shorter duration in their life and performed fewer foraging trips. Nursing behavior appeared to be unaffected by rearing condition. Weight was also unaffected by rearing condition. Interestingly, juvenile hormone titers, which normally increase strongly around the time when a honeybee becomes a forager, were significantly lower in three- and four-week-old in vitro bees. The effects of the rearing environment on individual sucrose responsiveness and lipid levels were rather minor. These data suggest that larval rearing conditions can affect the task performance and physiology of adult bees despite equal weight, pointing to an important role of the colony environment for these factors. Our observations of behavior and metabolic pathways offer important novel insight into how the rearing environment affects adult honeybees. [ABSTRACT FROM AUTHOR]

Simple Summary: Eucryptorrhynchus scrobiculatus (Motschulsky) and E. brandti (Harold) are significant pests of tree of heaven, Ailanthus altissima, often leading to tree death. Monitoring systems that involve host–plant based attractants need to be developed for both insect pest species. Here, we compared the behavioral and electrophysiological responses of E. scrobiculatus and E. brandti to volatiles emitted by various parts of the host plant. Host plant-derived volatiles showed to play a greater role in the foraging behavior of E. brandti than in E. scrobiculatus. Volatile components of phloem were found to be particularly attractive to E. brandti. Eucryptorrhynchus scrobiculatus and E. brandti (Coleoptera: Curculionidae) are host-specific pests of Ailanthus altissima (Mill.) Swingle (Sapindales: Simaroubaceae), causing extensive damage to the host. There are no effective attractants available for pest management. The main aim of this study was to explore the role of host plant-derived volatiles in the behavioral response of both weevil species. In a field experiment, both weevil species showed positive response to phloem, and there was no preference for phloem associated with healthy or injured trees. Significantly more E. brandti adults responded to the olfactory treatments compared to E. scrobiculatus. In a large-arena experiment, both males and females of E. scrobiculatus significantly preferred phloem from the tree trunk while adults of E. brandti responded in significantly greater numbers to tree limbs than to any other parts of host. Females and males of E. scrobiculatus responded positively to all parts of host tested in the Y-tube bioassay, while E. brandti adults were only attracted by the phloem from healthy and injured trees. There were dissimilar electroantennographic responses to compounds such as 1-hexanol and (1S)-(−)-β-pinene between the two weevil species. This study represents the first report documenting behavioral and electrophysiological responses of E. scrobiculatus and E. brandti to volatiles from various parts of A. altissima and findings may aid efforts to develop attractants. [ABSTRACT FROM AUTHOR]