@article {11984,
	title = {Factors influencing pine engraver (Ips pini Say) colonization of ponderosa pine (Pinus ponderosa Dougl. ex. Laws.) slash in Northern Arizona},
	journal = {Forest Ecology and Management},
	volume = {255},
	number = {8-9},
	year = {2008},
	month = {15 May},
	pages = {3541-3548},
	type = {Article},
	abstract = {Thinning projects have increased in recent years to reduce standing fuels and fire hazard within the Wildland Urban Interface (WUI) and to improve general forest conditions through forest health restoration treatments. As a consequence, large volumes of thinning slash have been generated, increasing the potential for growth of bark beetle (Ips spp.) populations. Because slash can initiate outbreaks in standing trees, a critical examination of slash management guidelines is needed to minimize bark beetle impacts associated with thinning treatments. Specifically, we examined effects of season of slash cutting, sunlight intensity (stand density) and log size on pine engraver (Ips pini Say) reproduction in North-central Arizona, USA. Ponderosa pine (Pinus ponderosa Dougl ex. Laws.) trees were felled and cut to 16 sizes (diameters of 10, 15, 20, and 25 cm and lengths of 15, 30, 45, and 60 cm) in October, January, April and July, for 2 years. The 16 logs of differing size were placed in groups in overstory stand densities of 5, 14, and 27.5 m2/ha (representing high, partial, and low sunlight levels). Response variables included attack density, emergence density, and beetle population growth rate. Log length had a positive relationship with both attack and emergence density. Log diameter had a significant effect on attack and emergence density, with a preference shown for intermediate diameter bolts. During a year with above average winter precipitation, cutting date and the interaction of cutting date and light level had significant effects on attack density. Fewer beetles attacked both bolts that had been exposed for longer periods of time and logs exposed to high sunlight levels. Cutting date, and the interaction of cutting date and light level, influenced emergence density, but light level alone did not. Emergence density was lowest in spring-cut logs in both years. Cutting date also had an effect on beetle population growth rate, with fall-cut logs having the highest population growth, while light level had no effect. Extended time-since-cutting (e.g. fall cutting), high light levels and small log diameter did not consistently cause reductions in beetle attack and reproductive performance as was hypothesized. Implications of these results for slash management guidelines are discussed.},
	keywords = {Ips pini},
	isbn = {0378-1127},
	author = {Hayes, Christopher J. and DeGomez, Tom E. and McMillin, Joel D. and Anhold, John A. and Hofstetter, Richard W.}
}
@article {11288,
	title = {Antennally mediated negative feedback regulation of pheromone production in the pine engraver beetle, Ips pini},
	journal = {Naturwissenschaften},
	volume = {94},
	number = {1},
	year = {2007},
	month = {January},
	pages = {61-64},
	abstract = {Bark beetles use monoterpenoid aggregation pheromones to coordinate host colonization and mating. These chemical signals are produced de novo in midgut cells via the mevalonate pathway, and pheromone production may be regulated by a negative feedback system mediated through the antennae. In this study, we explored the effect of antennectomy on pheromone production and transcript levels of key mevalonate pathway genes in juvenile hormone III-treated male pine engraver beetles, Ips pini (Say). Antennectomized males produced significantly greater amounts of pheromone than podectomized males and those with intact antennae. Likewise, mRNA levels of three mevalonate pathway genes important in pheromone biosynthesis were measured by quantitative real-time PCR and found to be induced to a greater extent with antennectomy, suggesting a transcriptional regulation of pheromone production},
	keywords = {Ips pini},
	isbn = {0028-1042},
	author = {Ginzel, Matthew D. and Bearfield, Jeremy C. and Keeling, Christopher I. and McCormack, Colin C. and Blomquist, Gary J. and Tittiger, Claus}
}
@article {11285,
	title = {Unique animal prenyltransferase with monoterpene synthase activity},
	journal = {Naturwissenschaften},
	volume = {96},
	number = {6},
	year = {2009},
	month = {June},
	pages = {731-735},
	abstract = {Monoterpenes are structurally diverse natural compounds that play an essential role in the chemical ecology of a wide array of organisms. A key enzyme in monoterpene biosynthesis is geranyl diphosphate synthase (GPPS). GPPS is an isoprenyl diphosphate synthase that catalyzes a single electrophilic condensation reaction between dimethylallyl diphosphate (C5) and isopentenyl diphosphate (C5) to produce geranyl diphosphate (GDP; C10). GDP is the universal precursor to all monoterpenes. Subsequently, monoterpene synthases are responsible for the transformation of GDP to a variety of acyclic, monocyclic, and bicyclic monoterpene products. In pheromone-producing male Ips pini bark beetles (Coleoptera: Scolytidae), the acyclic monoterpene myrcene is required for the production of the major aggregation pheromone component, ipsdienol. Here, we report monoterpene synthase activity associated with GPPS of I. pini. Enzyme assays were performed on recombinant GPPS to determine the presence of monoterpene synthase activity, and the reaction products were analyzed by coupled gas chromatography-mass spectrometry. The functionally expressed recombinant enzyme produced both GDP and myrcene, making GPPS of I. pini a bifunctional enzyme. This unique insect isoprenyl diphosphate synthase possesses the functional plasticity that is characteristic of terpene biosynthetic enzymes of plants, contributing toward the current understanding of product specificity of the isoprenoid pathway.},
	keywords = {Ips pini},
	isbn = {0028-1042},
	author = {Gilg, Anna B. and Tittiger, Claus and Blomquist, Gary J.}
}
@article {11141,
	title = {Influence of temperature on spring flight initiation for southwestern ponderosa pine bark beetles (Coleoptera: Curculionidae, Scolytinae)},
	journal = {Environmental Entomology},
	volume = {37},
	number = {1},
	year = {2008},
	month = {February},
	pages = {57-69},
	type = {Article},
	abstract = {Determination of temperature requirements for many economically important insects is a cornerstone of pest management. For bark beetles (Coleoptera: Curculionidae, Scolytinae), this information can facilitate timing of management strategies. Our goals were to determine temperature predictors for flight initiation of three species of Ips bark beetles, five species of Dendroctonus bark beetles, and two genera of bark beetle predators, Enoclerus spp. (Coleoptera: Cleridae) and Temnochila chlorodia (Mannerheim) (Coleoptera: Ostomidae), in ponderosa pine forests of northcentral Arizona. We quantified beetle flight activity using data loggers and pheromone-baited funnel traps at 18 sites over 4 yr. Ambient air temperature was monitored using temperature data loggers located in close proximity to funnel traps. We analyzed degree-day accumulation and differences between minimum, average, and maximum ambient temperature for the week before and week of first beetle capture to calculate flight temperature thresholds. Degree-day accumulation was not a good predictor for initiation of beetle flight. For all species analyzed other than D. adjunctus Blandford, beetles were captured in traps only when springtime temperatures exceeded 15.0[degree]C. D. adjunctus was collected when maximum temperatures reached only 14.5[degree]C. Once initial flights had begun, beetles were often captured when maximum ambient air temperatures were below initial threshold temperatures. Maximum and average air temperatures were a better predictor for beetle flight initiation than minimum temperature. We establish a temperature range for effective monitoring of bark beetles and their predators, and we discuss the implications of our results under climate change scenarios},
	keywords = {Dendroctonus brevicornis, Dendroctonus frontalis, Dendroctonus ponderosae, Dendroctonus valens, Enoclerus, Ips lecontei, Ips pini},
	isbn = {0046-225X},
	author = {Gaylord, M. L. and Williams, K. K. and Hofstetter, R. W. and McMillin, J. D. and Degomez, T. E. and Wagner, M. R.}
}
@article {10899,
	title = {Assessing forest vulnerability and the potential distribution of pine beetles under current and future climate scenarios in the Interior West of the US},
	journal = {Forest Ecology and Management},
	volume = {262},
	number = {3},
	year = {2011},
	month = {Aug 1},
	pages = {307-316},
	abstract = {The aim of our study was to estimate forest vulnerability and potential distribution of three bark beetles (Curculionidae: Scolytinae) under current and projected climate conditions for 2020 and 2050. Our study focused on the mountain pine beetle (Dendroctonus ponderosae), western pine beetle (Dendroctonus brevicomis), and pine engraver (Ips pini). This study was conducted across eight states in the Interior West of the US covering approximately 2.2 million km2 and encompassing about 95\% of the Rocky Mountains in the contiguous US. Our analyses relied on aerial surveys of bark beetle outbreaks that occurred between 1991 and 2008. Occurrence points for each species were generated within polygons created from the aerial surveys. Current and projected climate scenarios were acquired from the WorldClim database and represented by 19 bioclimatic variables. We used Maxent modeling technique fit with occurrence points and current climate data to model potential beetle distributions and forest vulnerability. Three available climate models, each having two emission scenarios, were modeled independently and results averaged to produce two predictions for 2020 and two predictions for 2050 for each analysis. Environmental parameters defined by current climate models were then used to predict conditions under future climate scenarios, and changes in different species{\textquoteright} ranges were calculated. Our results suggested that the potential distribution for bark beetles under current climate conditions is extensive, which coincides with infestation trends observed in the last decade. Our results predicted that suitable habitats for the mountain pine beetle and pine engraver beetle will stabilize or decrease under future climate conditions, while habitat for the western pine beetle will continue to increase over time. The greatest increase in habitat area was for the western pine beetle, where one climate model predicted a 27\% increase by 2050. In contrast, the predicted habitat of the mountain pine beetle from another climate model suggested a decrease in habitat areas as great as 46\% by 2050. Generally, 2020 and 2050 models that tested the three climate scenarios independently had similar trends, though one climate scenario for the western pine beetle produced contrasting results. Ranges for all three species of bark beetles shifted considerably geographically suggesting that some host species may become more vulnerable to beetle attack in the future, while others may have a reduced risk over time. [copyright]2011 Elsevier B.V. All rights reserved.},
	keywords = {Dendroctonus brevicomis, Dendroctonus ponderosae, Ips pini},
	isbn = {0378-1127},
	author = {Evangelista, Paul H. and Kumar, Sunil and Stohlgren, Thomas J. and Young, Nicholas E.}
}
@article {10746,
	title = {The genetic architecture of pheromone production between populations distant from the hybrid zone of the pine engraver, Ips pini},
	journal = {Chemoecology},
	volume = {17},
	number = {4},
	year = {2007},
	month = {September},
	pages = {255-262},
	abstract = {Across North America, populations of the pine engraver, Ips pini, differ in their expressed ratios of the two enantiomers of ipsdienol, the main component of its aggregation pheromone. We confirm previous studies, showing that the percentage of (+)-ipsdienol ranged from approximately 40 to 70\% for New York (NY) males and less then 5\% for California (CA) males. We performed line crosses including the F1, F2, and backcross generations between these populations. These line crosses showed that most F1 hybrids produced an intermediate enantiomeric blend of ipsdienol that was closer to the CA blend, with a frequency distribution peak near 15\% (+)-ipsdienol. There was also strong segregation to either parental type in the F2 and backcross generations, but not in a pattern that could be clearly described by a single autosomal locus. There was also an X-linked effect that caused some individuals in the F1 to have phenotypes more characteristic of NY populations. Generation means analysis confirms this X-linked effect, and also suggests a complicated autosomal dominance by dominance epistatic interaction. Despite the appearance of segregation, these results suggest a more complicated system of pheromone blend control than the single major gene previously found between divergent lines for high and low (+)-ipsdienol blends from the hybrid zone in British Columbia.},
	keywords = {Ips pini},
	isbn = {0937-7409},
	author = {Domingue, Michael J. and Teale, Stephen A.}
}
@article {10721,
	title = {Test of Nonhost Angiosperm Volatiles and Verbenone to Protect Trap Trees for Sirex noctilio (Hymenoptera: Siricidae) From Attacks by Bark Beetles (Coleoptera: Scolytidae) in the Northeastern United States},
	journal = {Journal of Economic Entomology},
	volume = {103},
	number = {6},
	year = {2010},
	month = {Dec},
	pages = {2094-2099},
	abstract = {Sirex noctitio F. (Hymenoptera: Siricidae) is an invasive woodwasp, currently established in northeastern North America. In other regions of the world, stressed trap trees are used to monitor populations of S. noctilio and to provide inoculation points for the biological control nematode Deladenus siricidicola Bedding. However, the operational use of trap trees for S. noctitio in North America may be compromised by the large community of native organisms that inhabit stressed and dying pine trees. Common bark beetles such as Ips pini (Say) and Ips grandicollis (Eichhoff) (Coleoptera: Scolytidae) could potentially compete with S. noctilio and associates for resources on trap trees, possibly reducing the efficacy of trap trees as habitats for the woodwasp. In an attempt to develop a technology to mitigate this potential issue, three common semiochemical interruptants-conophthorin, green leaf volatile mix, and verbenone were tested for effectiveness in reducing arrivals of I. pint and I. grandicollis on trap trees treated with herbicides in northeastern United States. In addition, the effects of these compounds were determined independently with pheromone-baited multiple-funnel traps. None of the interruptants reduced numbers of I. pini or I. grandicollis either arriving on trap trees or caught in pheromone-baited traps. However, verbenone increased catches of I. grandicollis in traps baited with its pheromone, ipsenol. The mix of green leaf volatiles reduced catches of a native ambrosia beetle, Gnathotrichus materiarius (Fitch), whereas verbenone reduced trap catches of an exotic ambrosia beetle, Xylosandrus germanus (Blandford). Catches of X. germanus in traps adjacent to trap trees were enhanced with conophthorin.},
	keywords = {Gnathotrichus materiarius, Ips grandicollis, Ips pini},
	isbn = {0022-0493},
	author = {Dodds, Kevin J. and Miller, Daniel R.}
}
@article {10645,
	title = {Composition of the bacterial community in the gut of the pine engraver, Ips pini (Say) (Coleoptera) colonizing red pine},
	journal = {Symbiosis},
	volume = {43},
	number = {2},
	year = {2007},
	month = {2007},
	pages = {97-104},
	abstract = {The gut bacterial community of a bark beetle, the pine engraver Ips pini (Say), was characterized using culture-dependent and culture- independent methods. Bacteria from individual guts of larvae, pupae and adults were cultured and DNA was extracted from samples of pooled larval guts. Analysis of 16S rRNA gene sequences amplified directly from the gut community suggests that the gut bacterial communities associated with I. pini are relatively simple, compared to many other systems. Six bacterial genera from four classes were detected by culturing gut bacteria from larvae, pupae and adults. Two genera, Pantoea and Stenotrophomonas ([gamma]-Proteobacteria) were found in all life stages of I. pini, consistently in larvae and adults, and less commonly in pupae. Sequences that affiliate with the Enterobactereaceae of the [gamma]-Proteobacteria were found in 95\% of the clones sampled. The Enterobactereaceae genera, Pantoea and Erwinia, accounted for 88\% of all clone sequences. These results are consistent with previous work indicating that another bark beetle, the southern pine beetle, Dendroctonus frontalis Zimmerman, also has a relatively simple gut flora, compared with wood colonizing insects such as wood borers and termites. The composition and abundance of bacteria associated with different life stages of I. pini are possibly associated with specific functions of the gut bacterial communities of larvae, pupae, and adults},
	keywords = {Ips pini},
	isbn = {0334-5114},
	author = {Delalibera, Italo, Jr. and Vasanthakumar, Archana and Burwitz, Benjamin J. and Schloss, Patrick D. and Klepzig, Kier D. and Handelsman, Jo and Raffa, Kenneth F.}
}
@article {10081,
	title = {Incomplete barriers to mitochondrial gene flow between pheromone races of the North American pine engraver, Ips pini (Say).},
	journal = {Proceedings of the Royal Society of London, Series B, Biological Sciences},
	volume = {266},
	year = {1999},
	note = {ORIG-Title-Journal-Volume-Combination:  Incomplete barriers to mitochondrial gene flow between pheromone races of the North American pine engraver, Ips pini (Say). Proceedings of the Royal Society of London 266},
	pages = {1843-1850},
	keywords = {Ips pini},
	author = {Cognato, A.I. and Seybold, S.J. and  Sperling, F.A.H.}
}
@article {9853,
	title = {Survey and phylogenetic analysis of culturable microbes in the oral secretions of three bark beetle species},
	journal = {Entomologia Experimentalis Et Applicata},
	volume = {131},
	number = {2},
	year = {2009},
	month = {May},
	pages = {138-147},
	abstract = {In a recent study, we reported a previously undescribed behavior in which a bark beetle exuded oral secretions containing bacteria that have antifungal properties, and hence defend their galleries against pervasive antagonistic Hyphomycete fungi. Actinobacteria, a group known for their antibiotic properties, were the most effective against fungi that invade the spruce beetle galleries. In the present study, we describe the isolation and identification of microorganisms from oral secretions of three bark beetles (Coleoptera: Curculionidae: Scolytinae): the spruce beetle, Dendroctonus rufipennis Kirby, the mountain pine beetle, Dendroctonus ponderosae Hopkins, and the pine engraver, Ips pini Say. Bacteria isolated from these three species span the major bacterial classes [alpha]-, [beta]-, and [gamma]-Proteobacteria, Firmicutes, Bacteroidetes, and Actinobacteria, except for D. ponderosae, which yielded no [alpha]-proteobacteria or Bacteroidetes isolates. Spruce beetles and pine engraver beetles had similar numbers of [alpha]-proteobacteria isolates, but pine engravers yielded twice as many Bacteroidetes isolates as spruce beetles. In contrast, mountain pine beetles yielded more isolates in the [beta]- and [gamma]-proteobacteria than spruce beetles and pine engravers. The highest percentage of Actinobacteria was obtained from spruce beetles, followed by pine engravers and mountain pine beetles. All of the fungal isolates obtained from the three beetle species were Ascomycetes. The greatest fungal diversity was obtained in spruce beetles, which had nine species, followed by pine engravers with five, and mountain pine beetles with one.},
	keywords = {Dendroctonus ponderosae, Dendroctonus rufipennis, Ips pini},
	isbn = {0013-8703},
	author = {Cardoza, Yasmin J. and Vasanthakumar, Archana and Suazo, Alonso and Raffa, Kenneth F.}
}
@article {9447,
	title = {Assemblage of Hymenoptera arriving at logs colonized by Ips pini (Coleoptera: Curculionidae: Scolytinae) and its microbial symbionts in western Montana},
	journal = {Canadian Entomologist},
	volume = {141},
	number = {2},
	year = {2009},
	month = {March-April},
	pages = {172-199},
	abstract = {Colonization of a tree by bark beetles and their symbionts creates a new habitat for a diverse assemblage of arthropods, including competing herbivores, xylophages, fungivores, saprophages, predators, and parasitoids. Understanding these assemblages is important for evaluating, nontarget effects of various management tactics and for subsequently evaluating how changes in climate, the presence of invasive species. and altered forestry practices and land-use tenure may affect biodiversity. We characterized the assemblage of hymenopterans attracted to logs of ponderosa pine (Pinus ponderosa C. Lawson (Pinaceae)) colonized by the bark beetle Ips pini (Say) and its microbial symbionts. In one experiment, the composition and relative abundances, of species arriving at hosts colonized by I. pini, and possible sources of attraction, were determined. Treatments consisted of a loo containing I. pini with its natural complement of microorganisms, a log alone, and a blank control. A second experiment was carried out to determine whether or not Hymenoptera were attracted to microbial symbionts of I. pini. Treatments consisted of a blank control, a to, alone, a lop containing L pini with its natural complement of microrganisms, either Ophiostoma ips, Burk-holderia sp., or Pichia scolyti. and a log inoculated with a combination of these three microorganisms. Over 2 years, 5163 Hymenoptera were captured, of which over 98\% were parasitoids. Braconidae, Platygastridae, Encyrtidae. Pteromalidae, and Ichneumonidae were the most abundant. Seven known species of bark beetle parasitoids (all Pteromalidae) were captured. However. parasitoids of Diptera, Lepidoptera, Hymenoptera. and non-wood-boring Coleoptera were also common. Nineteen species showed preferential attraction to host plants infested with I. pini and its complement of microorganisms, host plants inoculated with I. pini microbial symbionts, or host plants alone. Interestingly, many of these species were parasitoids of phytophagous, fungivorous, and saprophytic insects rather than of bark beetles themselves. These results Suggest that a diverse assemblage of natural enemies that attack various feeding guilds within a common habitat exploit common olfactory cues.},
	keywords = {Ips pini},
	isbn = {0008-347X},
	author = {Boone, Celia K. and Six, Diana L. and Krauth, Steven J. and Raffa, Kenneth F.}
}
@article {9448,
	title = {The enemy of my enemy is still my enemy: competitors add to predator load of a tree-killing bark beetle},
	journal = {Agricultural and Forest Entomology},
	volume = {10},
	number = {4},
	year = {2008},
	month = {November},
	pages = {411-421},
	type = {Article},
	abstract = {1 The mountain pine beetle Dendroctonus ponderosae is a major tree-killing bark beetle in North America. We evaluated how the subsequent arrival of a competing bark beetle Ips pini influences the arrival of predators and their impact on both species.2 The predators Temnochila chlorodia and Enoclerus sphegeus were strongly attracted to pheromones of D. ponderosae. By contrast, Enoclerus lecontei was mostly attracted to I. pini pheromones. The host compound myrcene synergized attraction of both D. ponderosae and E. sphegeus to the pheromone of D. ponderosae. However, it inhibited attraction of both I. pini and E. lecontei to I. pini{\textquoteright}s pheromone.3 Dendroctonus ponderosae were more attracted to trees than logs treated with its pheromones, whereas I. pini were more attracted to logs than trees treated with its pheromones. Some 78\% of T. chlorodia were captured at hosts baited with D. ponderosae pheromones, whereas 83\% of E. lecontei were captured at hosts baited with I. pini pheromones. We characterized the sequence of arrival to live trees baited with pheromones of D. ponderosae as: D. ponderosae, T. chlorodia, E. sphegeus, I. pini, E. lecontei.4 Various combinations of I. pini and predators were added to logs colonized by D. ponderosae in the above sequence of arrival observed in live trees baited with D. ponderosae aggregation pheromones. Ips pini reduced D. ponderosae adult brood production. However, the combination of I. pini and E. lecontei did not raise D. ponderosae brood production above that observed with only I. pini present. Similarly, the combination of I. pini and T. chlorodia did not reduce D. ponderosae brood production below that observed with I. pini alone. By contrast, the combination of I. pini, T. chlorodia and E. lecontei caused more brood loss to D. ponderosae than I. pini alone.5 Enoclerus lecontei did not reduce brood production by T. chlorodia, whereas T. chlorodia substantially reduced brood production by E. lecontei.6 Secondary bark beetles that exploit the resource created by primary tree-killing species exert negative effects through both competition and increased predator load. Implications to the population dynamics, ecology and evolution of tree-killing bark beetles are discussed.},
	keywords = {Dendroctonus ponderosae, Ips pini},
	isbn = {1461-9555},
	author = {Boone, Celia K. and Six, Diana L. and Raffa, Kenneth F.}
}
@article {9449,
	title = {Parasitoids and dipteran predators exploit volatiles from microbial symbionts to locate bark beetles},
	journal = {Environmental Entomology},
	volume = {37},
	number = {1},
	year = {2008},
	month = {February},
	pages = {150-161},
	type = {Article},
	abstract = {Host location by parasitoids and dipteran predators of bark beetles is poorly understood. Unlike coleopteran predators that locate prey by orienting to prey pheromones, wasps and flies often attack life stages not present until after pheromone production ceases. Bark beetles have important microbial symbionts, which could provide sources of cues. We tested host trees, trees colonized by beetles and symbionts, and trees colonized by symbionts alone for attractiveness to hymenopteran parasitoids and dipteran predators. Field studies were conducted with Ips pini in Montana. Three pteromalid wasps were predominant. All were associated with the second and third instars of L pini. Heydenia unica was more attracted to logs colonized by either I. pini or the fungus Ophiostoma ips than logs alone or blank controls (screen with no log). Rhopalicus pulchripennis was more attracted to logs colonized by L pini than logs alone or blank controls. Dibrachys cavus was attracted to logs but did not distinguish whether or not they were colonized. Two dolichopodid predators were predominant. A Medetera species was more attracted to colonized than uncolonized logs and more attracted to logs than blank controls. It was also more attracted to logs colonized with the yeast Pichia scolyti than uncolonized logs, but attraction was less consistent. An unidentified dolichopodid was more attracted to logs colonized with L pini, O. ips, and the bacteria Burkholderia sp., than to uncolonized logs, It was also attracted to uncolonized logs. Its responses were less consistent and pronounced than H. unica. These results suggest some parasitoids and dipteran predators exploit microbial symbionts of bark beetles to locate hosts. Overall, specialists showed strong attraction to fungal cues, whereas generalists were more attracted by plant volatiles. These results also show how microbial symbionts can have conflicting effects on host fitness},
	keywords = {Ips pini},
	isbn = {0046-225X},
	author = {Boone, Celia K. and Six, Diana L. and Zheng, Yanbing and Raffa, Kenneth F.}
}
@article {9241,
	title = {Two regulatory mechanisms of monoterpenoid pheromone production in Ips spp. of bark beetles},
	journal = {Journal of Chemical Ecology},
	volume = {35},
	number = {6},
	year = {2009},
	month = {June},
	pages = {689-697},
	abstract = {Bark beetles use aggregation pheromones to coordinate host colonization and mating. These monoterpenoid chemical signals are produced de novo in midgut cells via the mevalonate pathway, and pheromone production is induced when an adult beetle feeds on phloem of a host tree. In Ips pini, juvenile hormone (JH) III influences key regulatory enzymes along the mevalonate pathway that leads to pheromone production. In fact, topically applied JH III is sufficient to stimulate pheromone production in unfed males. In this study, we explore the influence of feeding and JH III treatment on pheromone production in male Ips confusus, the pinyon Ips. We also characterize the influence of feeding and JH III treatment on transcript levels and activity of three key enzymes involved in pheromone biosynthesis: 3-hydroxy-3-methylglutaryl-CoA (HMG) synthase (HMGS), HMG-CoA reductase (HMGR) and geranyl diphosphate synthase (GPPS). We also extend the current understanding of the regulation of pheromone biosynthesis in I. pini, by measuring the influence of feeding and JHIII treatment on enzymatic activity of HMGS and GPPS. Feeding on host phloem alone strongly induces pheromone production in male I. confusus, while JH III treatment has no effect. However, feeding and JH III both significantly up-regulate mRNA levels of key mevalonate pathway genes. Feeding up-regulates these genes to a maximum at 32 h, whereas with JH III-treatment, they are up-regulated at 4, 8, and 16 h, but return near to non-treatment levels at 32 h. Feeding, but not JH III treatment, also increases the activity of all three enzymes in I. confusus, while both feeding or treatment with JH III increase HMGS and GPPS activity in I. pini. Our data suggest that pheromone production in Ips is not uniformly controlled by JH III and feeding may stimulate the release of some other regulatory factor, perhaps a brain hormone, required for pheromone production.},
	keywords = {Ips, Ips pini},
	isbn = {0098-0331},
	author = {Bearfield, Jeremy C. and Henry, Anastasia G. and Tittiger, Claus and Blomquist, Gary J. and Ginzel, Matthew D.}
}
@article {9240,
	title = {Isolation, endocrine regulation and transcript distribution of a putative primary JH-responsive gene from the pine engraver, Ips pini (Coleoptera: Scolytidae)},
	journal = {Insect Biochemistry and Molecular Biology},
	volume = {38},
	number = {2},
	year = {2008},
	month = {February},
	pages = {256-267},
	type = {Article},
	abstract = {We isolated a cDNA of unknown function from a juvenile hormone III (JH III)-treated male midgut cDNA library prepared from the pine engraver beetle, Ips pini, and examined its genomic structure. The gene, tentatively named "Ipi10G08", encoded a 4 10 amino acid translation product that shared 26-37\% identity with unannotated matches from several insects. Semi-quantitative RT-PCR analysis of Ipi10G08 following application of a 10 [mu]g dose of JH III demonstrated an early induction for both male and female beetles, with transcripts being detectable after 45 min. An expression profile of male midgut tissue indicated Ipi10G08 transcript levels reach a maximum induction of [approximately]22.5-fold control levels at 4 h post-treatment. Tissue distribution studies displayed a large induction of Ipi10G08 mRNA in the alimentary canal of JH Ill-treated beetles, especially in males. A dose curve from both sexes suggested there may be a difference in the ability to respond to lower levels of JH III and immunoblot analysis indicated that although JH III highly induces transcript levels in females, protein levels are not similarly induced, while protein levels are induced in males. Ipi10G08 is likely a primary JH response gene and may provide insight into how this hormone exerts its actions. Published by Elsevier Ltd},
	keywords = {Ips pini},
	isbn = {0965-1748},
	author = {Bearfield, J. C. and Box, C. D. and Keeling, C. I. and Young, S. and Blomquist, G. J. and Tittiger, C.}
}
@article {8962,
	title = {Lack of genetic differentiation in aggressive and secondary bark beetles (Coleoptera: Curculionidae, Scolytinae) from Arizona},
	journal = {Environmental Entomology},
	volume = {37},
	number = {3},
	year = {2008},
	month = {June},
	pages = {817-824},
	type = {Article},
	abstract = {Bark beetles (Coleoptera: Curculionidae, Scolytinae) play an important role as disturbance agents in ponderosa pine (Pinus ponderosa Douglas ex Lawson) forests of Arizona. However, from 2001 to 2003, elevated bark beetle activity caused unprecedented levels of ponderosa pine mortality. A better understanding of the population structure of these species will facilitate analysis of their dispersal patterns and improve management strategies. Here, we use fluorescently labeled amplified fragment length polymorphism (fAFLP) analysis to resolve genetic variation among and within sampling locations in northcentral Arizona of Ips pini (Say), Dendroctonus brevicomis LeConte, and D. frontalis Zimmermann. We generated genetic fingerprints for >500 beetle specimens and analyzed genetic diversity. For all species, gene flow estimates among sampling locations were high, and significant population subdivision was not discernible across a large portion of ponderosa pine forests in Arizona. However, a weak relationship was detected with L pini population structure and elevation. Because of the lack of genetic differentiation detected throughout the large study area, our findings suggest these insects are capable of long distance dispersal and exhibit a high degree of gene flow across abroad region. We conclude that our results are consistent with strong dispersal patterns and large population sizes of all three species.},
	keywords = {Dendroctonus brevicomis, Dendroctonus frontalis, Ips pini},
	isbn = {0046-225X},
	author = {Allender, Christopher J. and Clancy, Karen M. and DeGomez, Tom E. and McMillin, Joel D. and Woolbright, Scott A. and Keim, Paul and Wagner, David M.}
}
