The genomes of two key bumblebee species with primitive eusocial organization

Background: The shift from solitary to social behavior is one of the major evolutionary transitions. Primitively eusocial bumblebees are uniquely placed to illuminate the evolution of highly eusocial insect societies. Bumblebees are also invaluable natural and agricultural pollinators, and there is widespread concern over recent population declines in some species. High-quality genomic data will inform key aspects of bumblebee biology, including susceptibility to implicated population viability threats. Results: We report the high quality draft genome sequences of Bombus terrestris and Bombus impatiens, two ecologically dominant bumblebees and widely utilized study species. Comparing these new genomes to those of the highly eusocial honeybee Apis mellifera and other Hymenoptera, we identify deeply conserved similarities, as well as novelties key to the biology of these organisms. Some honeybee genome features thought to underpin advanced eusociality are also present in bumblebees, indicating an earlier evolution in the bee lineage. Xenobiotic detoxification and immune genes are similarly depauperate in bumblebees and honeybees, and multiple categories of genes linked to social organization, including development and behavior, show high conservation. Key differences identified include a bias in bumblebee chemoreception towards gustation from olfaction, and striking differences in microRNAs, potentially responsible for gene regulation underlying social and other traits. Conclusions: These two bumblebee genomes provide a foundation for post-genomic research on these key pollinators and insect societies. Overall, gene repertoires suggest that the route to advanced eusociality in bees was mediated by many small changes in many genes and processes, and not by notable expansion or depauperation

Lawn and ornamentals research [1965]

Foreword / R. W. Kottman -- Quality lawn seed / D. W. Graffis -- Bentgrass varieties for golf courses and lawns / R. R. Davis and R. W. Miller -- Varieties of Kentucky bluegrass / R. W. Miller and R. R. Davis -- Maintenance fertilization of Kentucky bluegrass / R. R. David and R. W. Miller -- Crabgrass can be controlled / R. W. Miller and R. R. Davis -- Controlling broadleaf weeds in lawns / G. B. Triplett, Jr. and R. R. Davis -- Turf insect control / J. B. Polivka -- Ornamental crabapples / L. C. Chadwick -- Shade trees for Ohio lawns and streets / O. D. Diller and L. C. Chadwick -- Arboretums help beautify America / O. D. Diller -- Changing the grade level around trees / L. C. Chadwick and K. W. Reisch -- Anti-dessicants aid in transplanting shrubs / K. W. Reisch and E. M. Smith -- Growth retardants speed flowering / K. W. Reisch and P. C. Kozel -- Control of weeds in ground covers / L. C. Chadwick -- Chlorosis of pin oaks and other ornamental trees / L. C. Chadwick -- Diseases of woody ornamental plants / G. J. Bart -- A guide to the more common insect and mite pests of shade trees and ornamentals / R. W. Rings and W. K. Delaplane, Jr