02936nas a2200145   4500008004100000245010000041210006900141260000900210300001200219490000800231520238300239100002202622700002802644856011802672       2011                        eng d00aFrom Attack to Emergence: Interactions between Southern Pine Beetle, Mites, Microbes, and Trees0 aFrom Attack to Emergence Interactions between Southern Pine Beet  c2011  a141-1520 v1403 aBark beetles are among the most ecologically and economically influential organisms in forest ecosystems worldwide. These important organisms are consistently associated in complex symbioses with fungi. Despite this, little is known of the net impacts of the fungi on their vectors, and mites are often completely overlooked. In this chapter, we will describe interactions involving the southern pine beetle (SPB), among the most economically damaging of North American forest insects. We examine SPB interactions with mites, fungi, and other microbes, following the natural temporal progression from beetle attack to offspring emergence from trees. Associations with fungi are universal within bark beetles. Many beetle species possess specialized structures, termed mycangia, for the transport of fungi. The SPB consistently carries three main fungi and numerous mites into the trees it attacks. One fungus, Ophiostoma minus, is carried phoretically on the SPB exoskeleton and by phoretic mites. The mycangium of each female SPB may contain a pure culture of either Ceratocystiopsis ranaculosus or Tntomocorticiumr sp. A. The mycangial fungi are, by definition, transferred in a specific fashion. The SPB possesses two types of gland cells associated with the mycangium. The role of these cells and their products remains unknown. Preliminary studies have observed yeast-like fungal spores in the mycangium and several surrounding tubes that presumably carry secreted chemicals from gland cells (or bacteria) to the mycangium. The degree to which there is selective activity of the glandular chemical secretions remains to be seen. While O. minus may play some role in tree killing, none of these three fungi are highly virulent in their pine hosts. All three fungi grow within the phloem, sporulating heavily in beetle tunnels within which the SPB larvae graze. Though their ecological roles arc complex and context-dependent, these three fungi can be divided into an antagonist (O. minus) and two mutualists (both mycangial fungi, though F,ntnnmcorticium sp. A appears to be of greater benefit to the beetles than C. ranaculosus). Naturally, all three of the fungi compete for access to uncolonized pine phloem. The results of these competitions can have significant impacts on their beetle and mite hosts, and ultimately on the population dynamics of this destructive pest.1 aKlepzig, Kier, D.1 aHofstetter, Richard, W.  uhttps://weevil.myspecies.info/attack-emergence-interactions-between-southern-pine-beetle-mites-microbes-and-trees02235nas a2200229   4500008004100000020001400041245011600055210006900171260000800240300001200248490000700260520141800267653002701685653002801712100001601740700002101756700001901777700002801796700002201824700002401846856013501870       2011                        eng d  a0095-362800aPresence and Diversity of Streptomyces in Dendroctonus and Sympatric Bark Beetle Galleries Across North America0 aPresence and Diversity of Streptomyces in Dendroctonus and Sympa  cMay  a759-7680 v613 aRecent studies have revealed several examples of intimate associations between insects and Actinobacteria, including the Southern Pine Beetle Dendroctonus frontalis and the Spruce Beetle Dendroctonus rufipennis. Here, we surveyed Streptomyces Actinobacteria co-occurring with 10 species of Dendroctonus bark beetles across the United States, using both phylogenetic and community ecology approaches. From these 10 species, and 19 other scolytine beetles that occur in the same trees, we obtained 154 Streptomyces-like isolates and generated 16S sequences from 134 of those. Confirmed 16S sequences of Streptomyces were binned into 36 distinct strains using a threshold of 0.2% sequence divergence. The 16S rDNA phylogeny of all isolates does not correlate with the distribution of strains among beetle species, localities, or parts of the beetles or their galleries. However, we identified three Streptomyces strains occurring repeatedly on Dendroctonus beetles and in their galleries. Identity of these isolates was corroborated using a house-keeping gene sequence (efTu). These strains are not confined to a certain species of beetle, locality, or part of the beetle or their galleries. However, their role as residents in the woodboring insect niche is supported by the repeated association of their 16S and efTu from across the continent, and also having been reported in studies of other subcortical insects.10aDendroctonus frontalis10aDendroctonus rufipennis1 aHulcr, Jiri1 aAdams, Aaron, S.1 aRaffa, Kenneth1 aHofstetter, Richard, W.1 aKlepzig, Kier, D.1 aCurrie, Cameron, R.  uhttps://weevil.myspecies.info/presence-and-diversity-streptomyces-dendroctonus-and-sympatric-bark-beetle-galleries-across-north-am