02704nas a2200193   4500008004100000020001400041245011800055210006900173260000800242300001200250490000700262520200500269653001702274100002102291700002102312700001902333700002302352856013502375       2011                        eng d  a0098-033100aResponses of Bark Beetle-Associated Bacteria to Host Monoterpenes and Their Relationship to Insect Life Histories0 aResponses of Bark BeetleAssociated Bacteria to Host Monoterpenes  cAug  a808-8170 v373 aBark beetles that colonize living conifers and their microbial associates encounter constitutive and induced chemical defenses of their host. Monoterpene hydrocarbons comprise a major component of these allelochemicals, and many are antibiotic to insects, fungi, and bacteria. Some bark beetle species exhaust these defenses by killing their host through mass attacks mediated by aggregation pheromones. Others lack adult aggregation pheromones and do not engage in pheromone-mediated mass attacks, but rather have the ability to complete development within live hosts. In the former species, the larvae develop in tissue largely depleted of host terpenes, whereas in the latter exposure to these compounds persists throughout development. A substantial literature exists on how monoterpenes affect bark beetles and their associated fungi, but little is known of how they affect bacteria, which in turn can influence beetle performance in various manners. We tested several bacteria from two bark beetle species for their ability to grow in the presence of a diversity of host monoterpenes. Bacteria were isolated from the mountain pine beetle, Dendroctonus ponderosae Hopkins, which typically kills trees during colonization, and the red turpentine beetle, Dendroctonus valens LeConte, which often lives in their host without causing mortality. Bacteria from D. ponderosae were gram-positive Actinobacteria and Bacilli; one yeast also was tested. Bacteria from D. valens were Actinobacteria, Bacilli, and [gamma]-Proteobacteria. Bacteria from D. valens were more tolerant of monoterpenes than were those from D. ponderosae. Bacteria from D. ponderosae did not grow in the presence of [alpha]-pinene and 3-carene, and grew in, but were inhibited by, [beta]-pinene and [beta]-phellandrene. Limonene and myrcene had little inhibitory effect on bacteria from either beetle species. Tolerance to these antibiotic compounds appears to have resulted from adaptation to living in a terpene-rich environment.10aDendroctonus1 aAdams, Aaron, S.1 aBoone, Celia, K.1 aBohlmann, Jorg1 aRaffa, Kenneth, F.  uhttps://weevil.myspecies.info/responses-bark-beetle-associated-bacteria-host-monoterpenes-and-their-relationship-insect-life-histo02286nas a2200205   4500008004100000020001400041245012000055210006900175260001000244300001200254490000700266520153400273653002401807100002101831700002201852700002401874700002401898700002301922856013501945       2010                        eng d  a0046-225X00aGeographic Variation in Bacterial Communities Associated With the Red Turpentine Beetle (Coleoptera: Curculionidae)0 aGeographic Variation in Bacterial Communities Associated With th  cApril  a406-4140 v393 aBacterial communities are known to play important roles in insect life histories, yet their consistency or variation across populations is poorly understood. Bacteria associated with the bark beetle Dendroctonus valens Le Conte from eight populations, ranging from Wisconsin to Oregon, were evaluated and compared. We used the culture-independent technique of denaturing gradient gel electrophoresis to visualize bacterial diversity, or individual operational taxonomic units (Os), from individual beetles. One-way analysis of similarities was used to test for differences of bacterial communities between sites. Analysis of community profiles showed that individual beetles on average contained 10 OTUs, with frequency of association from 2 to 100% of beetles. OTU sequences most closely matched [beta]- and [gamma]-proteobacteria, and one each matched Bacilli and Actinobacteria. Several OTUs were particularly abundant, most notably an Actinobacterium from 100% and two Proteobacteria from 60% of beetles sampled. Some OTUs were similar to previously described bacteria with known biochemical capabilities and ecological functions, suggesting that some bacterial associates of D. valens may contribute to its ability to exploit a resource low in nutrients and high in defensive compounds. There were significant differences of bacterial communities between sites. The strength of these differences was positively correlated with distance between sites, although additional unexplained factors also contribute to the variation.10aDendroctonus valens1 aAdams, Aaron, S.1 aAdams, Sandye, M.1 aCurrie, Cameron, R.1 aGillette, Nancy, E.1 aRaffa, Kenneth, F.  uhttps://weevil.myspecies.info/geographic-variation-bacterial-communities-associated-red-turpentine-beetle-coleoptera-curculionidae