Here we report the genome sequence of the honeybee Apis mellifera, a key model for social behaviour and essential to global ecology through pollination. Compared with other sequenced insect genomes, the A. mellifera genome has high A+T and CpG contents, lacks major transposon families, evolves more slowly, and is more similar to vertebrates for circadian rhythm, RNA interference and DNA methylation genes, among others. Furthermore, A. mellifera has fewer genes for innate immunity, detoxification enzymes, cuticle-forming proteins and gustatory receptors, more genes for odorant receptors, and novel genes for nectar and pollen utilization, consistent with its ecology and social organization. Compared to Drosophila, genes in early developmental pathways differ in Apis, whereas similarities exist for functions that differ markedly, such as sex determination, brain function and behaviour. Population genetics suggests a novel African origin for the species A. mellifera and insights into whether Africanized bees spread throughout the New World via hybridization or displacement.

The fourth generation of the Sloan

Viruses are significant threats to the health and well-being of the honey bee, Apis mellifera. To alleviate the threats posed by these invasive organisms, a better understanding of bee viral infections will be of crucial importance in developing effective and environmentally benign disease control strategies. Although knowledge of honey bee viruses has been accumulated considerably in the past three decades, a comprehensive review to compile the various aspects of bee viruses at the molecular level has not been reported. This chapter summarizes recent progress in the understanding of the morphology, genome organization, transmission, epidemiology, and pathogenesis of honey bee viruses as well as their interactions with their honey bee hosts. The future prospects of research of honey bee viruses are also discussed in detail. The chapter has been designed to provide researchers in the field with updated information about honey bee viruses and to serve as a starting point for future research.

Across the Northern hemisphere, managed honey bee colonies, Apis mellifera, are currently affected by abrupt depopulation during winter and many factors are suspected to be involved, either alone or in combination. Parasites and pathogens are considered as principal actors, in particular the ectoparasitic mite Varroa destructor, associated viruses and the microsporidian Nosema ceranae. Here we used long term monitoring of colonies and screening for eleven disease agents and genes involved in bee immunity and physiology to identify predictive markers of honeybee colony losses during winter. The data show that DWV, Nosema ceranae, Varroa destructor and Vitellogenin can be predictive markers for winter colony losses, but their predictive power strongly depends on the season. In particular, the data support that V. destructor is a key player for losses, arguably in line with its specific impact on the health of individual bees and colonies.