Hansen, E. Matthew; Schopf, Axel; Ragland, Gregory J.; Stauffer, Christian; Bentz, Barbara J.
Abstract Diapause, a strategy to endure unfavourable conditions (e.g. cold winters) is commonly found in ectothermic organisms and is characterized by an arrest of development and reproduction, a reduction of metabolic rate, and an increased resistance to adversity. Diapause, in addition to adaptations for surviving low winter temperatures, significantly influences phenology, voltinism and ultimately population growth. We review the literature on diapause and overwintering behaviour of two bark beetle species that affect spruce‐dominated forests in the northern hemisphere, and describe and compare how these strategies can influence population dynamics. The European spruce bark beetle Ips typographus (L.) (Coleoptera, Curculionidae) is the most important forest pest of Norway spruce in Europe. It enters an adult reproductive diapause that might be either facultative or obligate. Obligate diapausing beetles are considered strictly univoltine, entering this dormancy type regardless of environmental cues. Facultative diapausing individuals enter diapause induced by photoperiod, modified by temperature, thus being potentially multivoltine. The spruce beetle Dendroctonus rufipennis (Kirby) (Coleoptera: Curculionidae) infests all spruce species in its natural range in North America. A facultative prepupal diapause is averted by relatively warm temperatures, resulting in a univoltine life cycle, whereas cool temperatures induce prepupal diapause leading to a semivoltine cycle. An adult obligate diapause in D. rufipennis could limit bi‐ or multivoltinism. We discuss and compare the influence of diapause and overwinter survival on voltinism and population dynamics of these two species in a changing climate and provide an outlook on future research. PMID:28979060
Gohli, Jostein; Kirkendall, Lawrence R; Smith, Sarah M; Cognato, Anthony I; Hulcr, Jiri; Jordal, Bjarte H
The study of species diversification can identify the processes that shape patterns of species richness across the tree of life. Here, we perform comparative analyses of species diversification using a large dataset of bark beetles. Three examined covariates-permanent inbreeding (sibling mating), fungus farming, and major host type-represent a range of factors that may be important for speciation. We studied the association of these covariates with species diversification while controlling for evolutionary lag on adaptation. All three covariates were significantly associated with diversification, but fungus farming showed conflicting patterns between different analyses. Genera that exhibited interspecific variation in host type had higher rates of species diversification, which may suggest that host switching is a driver of species diversification or that certain host types or forest compositions facilitate colonization and thus allopatric speciation. Because permanent inbreeding is thought to facilitate dispersal, the positive association between permanent inbreeding and diversification rates suggests that dispersal ability may contribute to species richness. Bark beetles are ecologically unique; however, our results indicate that their impressive species diversity is largely driven by mechanisms shown to be important for many organism groups. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.
Full Text Available Bark beetles (Scolytinae are hosts to a broad diversity of mites (Acari, including several genera of Oribatida (Sarcoptiformes. Of these, Paraleius (Scheloribatidae species are the most frequently collected oribatid mites associated with bark beetles. A new species was discovered while surveying the acarofauna of bark beetles in Eastern Canada and is described as Paraleius leahae sp. n. (Oribatida, Scheloribatidae. This species was collected from two host beetle species, Hylastes porculus Erickson and Dendroctonus valens LeConte, in Ontario, New Brunswick and Nova Scotia. The genus Paraleius is rediagnosed, Metaleius is considered a synonym of Paraleius, and the proposed synonymy of Paraleius with Siculobata is rejected. The three known species are Paraleius leontonycha (Berlese, P. leahae sp. n., and P. strenzkei (Travé, comb. n. The barcode region of cytochrome oxidase subunit I (COI was amplified from P. leahae sp. n.
Bark beetles (Scolytinae) are hosts to a broad diversity of mites (Acari), including several genera of Oribatida (Sarcoptiformes). Of these, Paraleius (Scheloribatidae) species are the most frequently collected oribatid mites associated with bark beetles. A new species was discovered while surveying the acarofauna of bark beetles in Eastern Canada and is described as Paraleius leahae sp. n. (Oribatida, Scheloribatidae). This species was collected from two host beetle species, Hylastes porculus Erickson and Dendroctonus valens LeConte, in Ontario, New Brunswick and Nova Scotia. The genus Paraleius is rediagnosed, Metaleius is considered a synonym of Paraleius , and the proposed synonymy of Paraleius with Siculobata is rejected. The three known species are Paraleius leontonycha (Berlese), P. leahae sp. n. , and P. strenzkei (Travé), comb. n. The barcode region of cytochrome oxidase subunit I (COI) was amplified from P. leahae sp. n.
Abstract Bark beetles (Scolytinae) are hosts to a broad diversity of mites (Acari), including several genera of Oribatida (Sarcoptiformes). Of these, Paraleius (Scheloribatidae) species are the most frequently collected oribatid mites associated with bark beetles. A new species was discovered while surveying the acarofauna of bark beetles in Eastern Canada and is described as Paraleius leahae sp. n. (Oribatida, Scheloribatidae). This species was collected from two host beetle species, Hylastes porculus Erickson and Dendroctonus valens LeConte, in Ontario, New Brunswick and Nova Scotia. The genus Paraleius is rediagnosed, Metaleius is considered a synonym of Paraleius, and the proposed synonymy of Paraleius with Siculobata is rejected. The three known species are Paraleius leontonycha (Berlese), P. leahae sp. n., and P. strenzkei (Travé), comb. n. The barcode region of cytochrome oxidase subunit I (COI) was amplified from P. leahae sp. n. PMID:28769635
Huang, Y-T; Kolařík, M; Kasson, M T; Hulcr, J
Species of Geosmithia are cosmopolitan but understudied fungi, and most are associated with phloem-feeding bark beetles on various woody hosts. We surveyed 207 bark and ambrosia beetles from 37 species in the eastern USA for associated fungi. The community is dominated by species in the G. pallida species complex (GPSC) and included several Geosmithia isolates that appear to be new to science. The new Geosmithia isolates exhibited the characteristic brownish-colored colonies typical for the G. pallida species complex and were phylogenetically resolved as two genealogically exclusive lineages based on a concatenated multilocus data set based on the internal transcribed spacers (ITS) of the nuc rDNA (ITS1-5.8S-ITS2 = ITS), and the translation elongation factor 1-α (TEF1-α), β-tubulin (TUB2), and RNA polymerase II second largest subunit (RPB2) genes. Two new Geosmithia species, G. brunnea and G. proliferans, are proposed, and their morphological traits and phylogenetic placements are presented.
Deepa S. Pureswaran; Richard W. Hofstetter; Brian Sullivan; Kristen A. Potter
When related species coexist, selection pressure should favor evolution of species recognition mechanisms to prevent interspecific pairing and wasteful reproductive encounters. We investigated the potential role of pheromone and acoustic signals in species recognition between two species of tree-killing bark beetles, the southern pine beetle, Dendroctonus frontalis...
Richard W. Hofstetter; John Moser; Stacy Blomquist
The role that mites play in many ecosystems is often overlooked or ignored. Within bark beetle habitats, more than 100 mite species exist and they have important impacts on community dynamics, ecosystem processes, and biodiversity of bark beetle systems. Mites use bark beetles to access and disperse among beetle-infested trees and the associations may range from...
The invasive European elm bark beetle, Scolytus multistriatus (Marsham), was first detected a century ago and now occurs in most of the continental United States. The invasive banded elm bark beetle, Scolytus schevyrewi Semenov, native to Asia, was discovered in the United States in 2003 and is now...
Mandelshtam, Michail Yu.; V. Petrov, Alexander
Abstract A new species of bark-beetle from Kashmir, Scolytus stepheni sp. n., dedicated to the late Professor Emeritus Stephen Lane Wood, is described and figured. Key to Indian Scolytus Geoffroy, 1762 species is provided. PMID:21594178
Slavimira A. Draganova
Full Text Available Bark beetles (Coleoptera: Curculionidae: Scolytinae belong to one of the most damaging groups of forest insects and the activity of their natural enemies –pathogens, parasitoids,parasites or predators suppressing their population density,is of great importance. Biodiversity of entomopathogenic fungi on bark beetles in Bulgaria has been investigated sporadically. The aim of this preliminary study was to find, identify and study morphological characteristics of fungal entomopathogens naturally-occurring in populations of three curculionid species – Ips sexdentatus Boern, Ips typographus (L. and Dryocoetes autographus (Ratz.. Dead pest adults were found under the bark of Pinus sylvestris and Picea abies trees collectedfrom forests in the Maleshevska and Vitosha Mountains. Fungal pathogens were isolated into pure cultures on SDAY (Sabouraud dextrose agar with yeast extract and were identified based on morphological characteristics both on the host and in a culture.Morphological characteristics of the isolates were studied by phenotypic methods. The fungal isolates obtained from dead adults of Ips sexdentatus, Ips typographus and D. autographus were found to belong to the species Beauveria bassiana (Bals. – Criv. Vuillemin,Beauveria brongniartii (Saccardo Petch and Isaria farinosa (Holmsk. Fries (anamorph Ascomycota, Sordariomycetes: Hypocreales, Cordycipitaceae. Morphological traits of the isolates are described.
Seybold, Steven J; Bentz, Barbara J; Fettig, Christopher J; Lundquist, John E; Progar, Robert A; Gillette, Nancy E
We summarize the status of semiochemical-based management of the major bark beetle species in western North America. The conifer forests of this region have a long history of profound impacts by phloem-feeding bark beetles, and species such as the mountain pine beetle (Dendroctonus ponderosae) and the spruce beetle (D. rufipennis) have recently undergone epic outbreaks linked to changing climate. At the same time, great strides are being made in the application of semiochemicals to the integrated pest management of bark beetles. In this review, we synthesize and interpret these recent advances in applied chemical ecology of bark beetles for scientists and land managers.
Blomquist, Gary J; Figueroa-Teran, Rubi; Aw, Mory; Song, Minmin; Gorzalski, Andrew; Abbott, Nicole L; Chang, Eric; Tittiger, Claus
The first aggregation pheromone components from bark beetles were identified in 1966 as a mixture of ipsdienol, ipsenol and verbenol. Since then, a number of additional components have been identified as both aggregation and anti-aggregation pheromones, with many of them being monoterpenoids or derived from monoterpenoids. The structural similarity between the major pheromone components of bark beetles and the monoterpenes found in the host trees, along with the association of monoterpenoid production with plant tissue, led to the paradigm that most if not all bark beetle pheromone components were derived from host tree precursors, often with a simple hydroxylation producing the pheromone. In the 1990 s there was a paradigm shift as evidence for de novo biosynthesis of pheromone components began to accumulate, and it is now recognized that most bark beetle monoterpenoid aggregation pheromone components are biosynthesized de novo. The bark beetle aggregation pheromones are released from the frass, which is consistent with the isoprenoid aggregation pheromones, including ipsdienol, ipsenol and frontalin, being produced in midgut tissue. It appears that exo-brevocomin is produced de novo in fat body tissue, and that verbenol, verbenone and verbenene are produced from dietary α-pinene in fat body tissue. Combined biochemical, molecular and functional genomics studies in Ips pini yielded the discovery and characterization of the enzymes that convert mevalonate pathway intermediates to pheromone components, including a novel bifunctional geranyl diphosphate synthase/myrcene synthase, a cytochrome P450 that hydroxylates myrcene to ipsdienol, and an oxidoreductase that interconverts ipsdienol and ipsdienone to achieve the appropriate stereochemistry of ipsdienol for pheromonal activity. Furthermore, the regulation of these genes and their corresponding enzymes proved complex and diverse in different species. Mevalonate pathway genes in pheromone producing male I. pini
Reed, Sharon E; Juzwik, Jennifer; English, James T; Ginzel, Matthew D
Thousand cankers disease (TCD) is a new disease of black walnut (Juglans nigra L.) in the eastern United States. The disease is caused by the interaction of the aggressive bark beetle Pityophthorus juglandis Blackman and the canker-forming fungus, Geosmithia morbida M. Kolarik, E. Freeland, C. Utley & Tisserat, carried by the beetle. Other insects also colonize TCD-symptomatic trees and may also carry pathogens. A trap tree survey was conducted in Indiana and Missouri to characterize the assemblage of ambrosia beetles, bark beetles, and other weevils attracted to the main stems and crowns of stressed black walnut. More than 100 trees were girdled and treated with glyphosate (Riverdale Razor Pro, Burr Ridge, Illinois) at 27 locations. Nearly 17,000 insects were collected from logs harvested from girdled walnut trees. These insects represented 15 ambrosia beetle, four bark beetle, and seven other weevil species. The most abundant species included Xyleborinus saxeseni Ratzburg, Xylosandrus crassiusculus Motschulsky, Xylosandrus germanus Blandford, Xyleborus affinis Eichhoff, and Stenomimus pallidus Boheman. These species differed in their association with the stems or crowns of stressed trees. Multiple species of insects were collected from individual trees and likely colonized tissues near each other. At least three of the abundant species found (S. pallidus, X. crassiusculus, and X. germanus) are known to carry propagules of canker-causing fungi of black walnut. In summary, a large number of ambrosia beetles, bark beetles, and other weevils are attracted to stressed walnut trees in Indiana and Missouri. Several of these species have the potential to introduce walnut canker pathogens during colonization. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: email@example.com.
Ken Gibson; Jose F. Negron
Bark beetle populations are at outbreak conditions in many parts of the western United States and causing extensive tree mortality. Bark beetles interact with other disturbance agents in forest ecosystems, one of the primary being fires. In order to implement appropriate post-fire management of fire-damaged ecosystems, we need a better understanding of...
T. Evan Nebeker
Dendroctonus frontalis (southern pine beetle), D. terebrans (black turpentine beetle), Ips avulsus (small southern pine engraver or four-spined engraver), I. grandicollis (five-spined engraver), and I. calligraphus (six-spined engraver) comprise the southern pine bark beetle guild. Often they are found sharing the same hosts in the Southeastern United States. They...
Paciura, D.; Beer, de Z.W.; Jacobs, K.; Zhou, X.D.; Ye, H.; Wingfield, M.J.
The timber and pulp industries of Finland rely heavily on importations from Russia as source of raw timber. These imports raise the risk of accidentally importing forest pests and pathogens, especially bark beetles and their associated fungi, into Finland. Although ophiostomatoid fungi have
Steininger, M S; Hulcr, J; Šigut, M; Lucky, A
Bark and ambrosia beetles (Coleoptera: Curculionidae: Scolytinae & Platypodinae) are among the most damaging forest pests worldwide, and monitoring is essential to damage prevention. Unfortunately, traps and attractants that are currently used are costly, and agencies rely on limited field personnel for deployment. The situation can be greatly aided by 1) the development of cost-effective trapping techniques, and 2) distribution of the effort through the Citizen Science approach. The goal of this study was to test a simple, effective trap that can be made and deployed by anyone interested in collecting bark and ambrosia beetles. Three trap types made from 2-liter soda bottles and, separately, four attractants were compared. Simple, one-window traps performed comparably at capturing species in traps painted or with multiple windows. A comparison of attractants in two-window traps found that 95% ethanol attracted the highest number of species but that Purell hand sanitizer (70% ethanol) and then Germ-X hand sanitizer (63% ethanol) were also effective. A perforated zip-top plastic bag containing Purell hanging over a trap filled with automobile antifreeze attracted the fewest species and individual specimens. Overall, >4,500 bark and ambrosia beetles, including 30 species were captured, representing a third of the regional species diversity. More than three quarters of the specimens were nonnative, representing nearly half of the known regional exotic species. These results suggest that simple one-window soda bottle traps baited with ethanol-based hand sanitizer will be effective and inexpensive tools for large-scale monitoring of bark and ambrosia beetles. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: firstname.lastname@example.org.
Romón, Pedro; de Beer, Z Wilhelm; Zhou, XuDong; Duong, Tuan A; Wingfield, Brenda D; Wingfield, Michael J
Ophiostoma species, some of which cause sapstain in timber and/or are mild pathogens, are common fungal associates of bark beetles (Coleoptera: Scolytinae). Three new Ophiostomataceae from Spain are recognized in the present study based on comparisons of sequence data for three gene regions as well as morphological characteristics. The new taxa are described as Ophiostoma nebulare sp. nov., Ophiostoma euskadiense sp. nov. and Graphilbum crescericum sp. nov.
Certain species of bark beetles in the insect order Coleoptera, family Curculionidae (formerly Scolytidae) are keystone species in forest ecosystems. However, the tree-killing and woodboring bark and ambrosia beetles are also among the most damaging insects of forest products including lumber, paper...
Faccoli, Massimo; Sidoti, Agatino
We describe a new species of pine bark beetle, Phloeosinus laricionis, associated with a pine decline recently affecting young plantations of Pinus nigra ssp. laricio Poiret growing on the Etna volcano, Sicily (South Italy). The new species is morphologically close to the group species of P. cedri Brisout, P. acatayi Schedl, and P. pfefferi Knížek, having all odd interstriae on the declivity of elytra bearing small, individual, sparse, more or less sharply pointed tubercles in males, or with smaller sparse blunt, nippled tubercles in females. While the other species of the same group live on cedars, the new species is the only Palaearctic Phloeosinus known from pine.
Davis, T S; Hofstetter, R W
Interspecific interactions among tree-killing bark beetle species may have ecologically important consequences on beetle population dynamics. Using two tree-killing beetle species (Dendroctonus brevicomis and D. frontalis), we performed observational and experimental studies to verify cross-attraction and co-colonization under field conditions in northern Arizona and test the effects of gallery density and species ratio on response variables of average gallery length, offspring size (progeny fitness), and offspring production per centimeter gallery (fecundity). Our results show that both D. frontalis and D. brevicomis aggregate to pheromones synthesized de novo by D. brevicomis under field conditions and that galleries of both D. brevicomis and D. frontalis occurred together in the same region of a single host tree with significant frequency. In experimental manipulations of species ratios, the presence of conspecific beetles in the gallery environment strongly mediated fecundity, but D. frontalis was the only species that suffered negative impacts from the presence of heterospecific beetles in the gallery environment. Interactions did not result in any apparent fitness effects for progeny of either species, which suggests that multispecies aggregations and co-colonization may be a dominant ecological strategy in the region and result in niche sharing.
Waalberg, Max Emil
Pityogenes bidentatus, P. quadridens and Ips acuminatus are known to be associated with fungi. However, little is known about the associations between the three beetle species and fungi in Norwegian Scots pine forest. This study reports species associated with the three beetle species in Norway. In total, 60 specimens P. bidentatus, 66 of P. quadridens, and 30 of I. acuminatus were collected and dissected. A total number of 560 fungal isolates including 46 species were obtained. In this study...
Waring, Kristen M.; Reboletti, Danielle M.; Mork, Lauren A.; Huang, Ching-Hsun; Hofstetter, Richard W.; Garcia, Amanda M.; Fulé, Peter Z.; Davis, T. Seth
Predicted climate warming is expected to have profound effects on bark beetle population dynamics in the southwestern United States. Temperature-mediated effects may include increases in developmental rates, generations per year, and changes in habitat suitability. As a result, the impacts of Dendroctonus frontalis and Dendroctonus mexicanus on forest resources are likely subject to amplification. To assess the implications of such change, we evaluated the generations per year of these species under three climate scenarios using a degree-day development model. We also assessed economic impacts of increased beetle outbreaks in terms of the costs of application of preventative silvicultural treatments and potential economic revenues forgone. Across the southwestern USA, the potential number of beetle generations per year ranged from 1-3+ under historical climate, an increase of 2-4+ under the minimal warming scenario and 3-5+ under the greatest warming scenario. Economic benefits of applying basal area reduction treatments to reduce forest susceptibility to beetle outbreaks ranged from 7.75/ha (NM) to 95.69/ha (AZ) under historical conditions, and 47.96/ha (NM) to 174.58/ha (AZ) under simulated severe drought conditions. Basal area reduction treatments that reduce forest susceptibility to beetle outbreak result in higher net present values than no action scenarios. Coupled with other deleterious consequences associated with beetle outbreaks, such as increased wildfires, the results suggest that forest thinning treatments play a useful role in a period of climate warming.
Niño-Domínguez, Alicia; Sullivan, Brian T; López-Urbina, José H; Macías-Sámano, Jorge E
Where their geographic and host ranges overlap, sibling species of tree-killing bark beetles may simultaneously attack and reproduce on the same hosts. However, sustainability of these potentially mutually beneficial associations demands effective prezygotic reproductive isolation mechanisms between the interacting species. The pine bark beetle, Dendroctonus frontalis Zimmermann, is syntopic in the Central American region with a recently described sibling species, Dendroctonus mesoamericanus Armendáriz-Toledano and Sullivan, but mechanisms for their reproductive isolation are uncertain. We investigated whether semiochemicals mediate species discrimination by mate-seeking males of both species. In olfactometer bioassays, walking males of both species strongly preferred odors from gallery entrances of conspecific females. Coupled gas chromatography-electroantennographic detection and gas chromatography-mass spectrometry isolated 16 olfactory stimulants for males in these odors, but only two, ipsdienol and endo-brevicomin (both from D. mesoamericanus females), differed in quantity in female-associated odors between the species. In olfactometer bioassays, with 10, 1, or 0.1 female entrance equivalents of synthetic semiochemicals, the combination of ipsdienol and endo-brevicomin inhibited responses of male D. frontalis and enhanced responses of male D. mesoamericanus to two compounds associated with female entrances of both species (the pheromone component frontalin and host odor α-pinene). We conclude that ipsdienol and endo-brevicomin, pheromone components produced by females of just one of the two species (D. mesoamericanus), mediate interspecific mate discrimination by males of both species and provide an apparently symmetrical reproductive isolation mechanism.
Knee, Wayne; Beaulieu, Frédéric; Skevington, Jeffrey H; Kelso, Scott; Cognato, Anthony I; Forbes, Mark R
Understanding the ecology and evolutionary history of symbionts and their hosts requires accurate taxonomic knowledge, including clear species boundaries and phylogenies. Tortoise mites (Mesostigmata: Uropodoidea) are among the most diverse arthropod associates of bark beetles (Curculionidae: Scolytinae), but their taxonomy and host associations are largely unstudied. We tested the hypotheses that (1) morphologically defined species are supported by molecular data, and that (2) bark beetle uropodoids with a broad host range comprise cryptic species. To do so, we assessed the species boundaries of uropodoid mites collected from 51 host species, across 11 countries and 103 sites, using morphometric data as well as partial cytochrome oxidase I (COI) and nuclear large subunit ribosomal DNA (28S). Overall, morphologically defined species were confirmed by molecular datasets, with a few exceptions. Twenty-nine of the 36 uropodoid species (Trichouropoda, Nenteria and Uroobovella) collected in this study had narrow host ranges, while seven species had putative broad host ranges. In all but one species, U. orri, our data supported the existence of these host generalists, which contrasts with the typical finding that widespread generalists are actually complexes of cryptic specialists.
Full Text Available Understanding the ecology and evolutionary history of symbionts and their hosts requires accurate taxonomic knowledge, including clear species boundaries and phylogenies. Tortoise mites (Mesostigmata: Uropodoidea are among the most diverse arthropod associates of bark beetles (Curculionidae: Scolytinae, but their taxonomy and host associations are largely unstudied. We tested the hypotheses that (1 morphologically defined species are supported by molecular data, and that (2 bark beetle uropodoids with a broad host range comprise cryptic species. To do so, we assessed the species boundaries of uropodoid mites collected from 51 host species, across 11 countries and 103 sites, using morphometric data as well as partial cytochrome oxidase I (COI and nuclear large subunit ribosomal DNA (28S. Overall, morphologically defined species were confirmed by molecular datasets, with a few exceptions. Twenty-nine of the 36 uropodoid species (Trichouropoda, Nenteria and Uroobovella collected in this study had narrow host ranges, while seven species had putative broad host ranges. In all but one species, U. orri, our data supported the existence of these host generalists, which contrasts with the typical finding that widespread generalists are actually complexes of cryptic specialists.
M. Patricia Chaires-Grijalva; Edith G. Estrada-Venegas; Armando Equihua-Martinez; John C. Moser; Stacy R. Blomquist
Samples of bark and logs damaged by bark beetles were collected from 16 states of Mexico from 2007 to 2012. Fifteen bark beetle species were found within the bark and log samples and were examined for phoretic mites and arthropod associates. Thirty-three species of mesostigmatid mites were discovered within the samples. They were identified in several trophic guilds...
Kandasamy, Dineshkumar; Gershenzon, Jonathan; Hammerbacher, Almuth
Conifer bark beetles attack and kill mature spruce and pine trees, especially during hot and dry conditions. These beetles are closely associated with ophiostomatoid fungi of the Ascomycetes, including the genera Ophiostoma, Grosmannia, and Endoconidiophora, which enhance beetle success by improving nutrition and modifying their substrate, but also have negative impacts on beetles by attracting predators and parasites. A survey of the literature and our own data revealed that ophiostomatoid fungi emit a variety of volatile organic compounds under laboratory conditions including fusel alcohols, terpenoids, aromatic compounds, and aliphatic alcohols. Many of these compounds already have been shown to elicit behavioral responses from bark beetles, functioning as attractants or repellents, often as synergists to compounds currently used in bark beetle control. Thus, these compounds could serve as valuable new agents for bark beetle management. However, bark beetle associations with fungi are very complex. Beetle behavior varies with the species of fungus, the stage of the beetle life cycle, the host tree quality, and probably with changes in the emission rate of fungal volatiles. Additional research on bark beetles and their symbiotic associates is necessary before the basic significance of ophiostomatoid fungal volatiles can be understood and their applied potential realized.
John D. Reeve
Bark beetle populations may undergo dramatic fluctuations and are often important pests in coniferous forests.Their dynamics are thought to be primarily driven by factors affecting the resistance of the host tree to attack, i.e., bottom-up forces, while natural enemies are usually assigned a minor role in these systems.I present behavioral experiments that suggest that...
Michael G. Ryan; Gerard Sapes; Anna Sala; Sharon Hood
Irruptive bark beetles usually co-occur with their co-evolved tree hosts at very low (endemic) population densities. However, recent droughts and higher temperatures have promoted widespread tree mortality with consequences for forest carbon, fire and ecosystem services (Kurz et al., 2008; Raffa et al., 2008; Jenkins et al., 2012). In this issue of New Phytologist,...
Zhu, Jun; Rasmussen, Jakob Gulddahl; Møller, Jesper
red turpentine beetle colonization, pine engraver bark beetle colonization, and mortality of red pine trees while accounting for correlation across space and over time. We extend traditional Markov random-field models to include temporal terms and multiple-response variables aimed at developing...... as well as posterior predictive distributions. In particular, we implement path sampling combined with perfect simulation for autologistic models while formally addressing the posterior propriety under an improper uniform prior. Our data analysis results suggest that red turpentine beetle colonization...... is associated with a higher likelihood of pine engraver bark beetle colonization and that pine engraver bark beetle colonization is associated with higher likelihood of red pine tree mortality, whereas there is no direct association between red turpentine beetle colonization and red pine tree mortality...
Thelma J. Perry
Taxonomic revisions in both the teleomorphic (sexual) and anamorphic (asexual) forms of the genus Ceratocystis Ellis & Halstead are chronicled in this review. Recognized species associated with Dendroctonus Erichson bark beetles are summarized, and several species that have been published as recombinations, species that were...
W. R. Jacobi; R. D. Koski; J. F. Negron
Dutch Elm Disease (DED) is a vascular wilt disease of Ulmus species (elms) incited in North America primarily by the exotic fungus Ophiostoma novo-ulmi. The pathogen is transmitted via root grafts and elm bark beetle vectors, including the native North American elm bark beetle, Hylurgopinus rufipes and the exotic smaller European elm bark beetle, Scolytus multistriatus...
Full Text Available Fifteen species of ambrosia beetles and two bark beetle belonging to the curculionid subfamilies Scolytinae andPlatypodinae (Coleoptera: Curculionidae were collected from three infested mango trees (Mangifera indica L. in theresearch orchards of the Faculty of Natural Resources, Prince of Songkla University, Songkhla Province. Two species,Arixyleborus grandis (Schedl and Xyleborinus sculptilis (Schedl, are recorded for the first time in Thailand.
Machingambi, Netsai M; Roux, Jolanda; Dreyer, Léanne L; Roets, Francois
Bark and ambrosia beetles are ecologically and economically important phloeophagous insects that often have complex symbiotic relationships with fungi and mites. These systems are greatly understudied in Africa. In the present study we identified bark and ambrosia beetles, their phoretic mites and their main fungal associates from native Virgilia trees in the Cape Floristic Region (CFR) of South Africa. In addition, we tested the ability of mites to feed on the associated fungi. Four species of scolytine beetles were collected from various Virgilia hosts and from across the CFR. All were consistently associated with various Geosmithia species, fungi known from phloeophagous beetles in many parts of the world, but not yet reported as Scolytinae associates in South Africa. Four beetle species, a single mite species and five Geosmithia species were recovered. The beetles, Hapalogenius fuscipennis, Cryphalini sp. 1, and Scolytoplatypus fasciatus were associated with a single species of Elattoma phoretic mite that commonly carried spores of Geosmithia species. Liparthrum sp. 1 did not carry phoretic mites. Similar to European studies, Geosmithia associates of beetles from Virgilia were constant over extended geographic ranges, and species that share the same host plant individual had similar Geosmithia communities. Phoretic mites were unable to feed on their Geosmithia associates, but were observed to feed on bark beetle larvae within tunnels. This study forms the first African-centred base for ongoing global studies on the associations between arthropods and Geosmithia species. It strengthens hypotheses that the association between Scolytinae beetles and dry-spored Geosmithia species may be more ubiquitous than commonly recognised. Copyright © 2014 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.
Full Text Available Hindgut volatiles from attacking, unmated males of Ips avulsus, I. calligraphus, I. grandicollis, and I. pini were analyzed by combined gas chromatography and mass spectrometry. Based on the quantitative identifications of hindguts and subsequent individual aerations, baits were formulated and a combined species-specific subtractive field bioassay was set up for the four bark beetle species. The bioassays were subtractive for the compounds identified in the hindgut analysis of each species, and volatiles identified in sympatric species were added as potential inhibitors alone and in combination. The trap catches from this bioassay revealed strong interspecific inhibition. The subtractive assays showed that I. grandicollis and I. calligraphus share (–-(4S-cis-verbenol as one pheromone component, while their second, synergistic pheromone component, (–-(S-ipsenol in I. grandicollis and (±-ipsdienol in I. calligraphus, acts as an interspecific inhibitor to the other species. I. avulsus and I. pini were found to have very similar production of hindgut volatiles, and both use ipsdienol and lanierone as synergistic pheromone components. No beetle-produced interspecific inhibitor was identified between these two species. Lanierone was found to be an interspecific inhibitor for both I. calligraphus and I. grandicollis.
Wojciech L. Magowski; Evert E. Lindquist; John C. Moser
A new genus and species of the mite family Tarsonemidae, subfamily Tarsoneminae, is described and illustrated. Its systematic position among genera of Tarsoneminae and its host association with bark beetles of the genus Pseudopityophthorus Swaine, 1918 in North America are briefly discussed.
George T. Ferrell; J. Richard Parmeter Jr.
Associations between root diseases and bark beetles (Scolytidae) constitute some of the most serious pest complexes affecting forests in North America and elsewhere. The interactive functioning of these pests derives from the following relationships: 1) root diseases predispose trees to bark beetle infestation by lowering resistance, and perhaps...
Paulius Zolubas; Jose Negron; A. Steven Munson
Spruce bark beetle (Ips typographus L.) risk model, based on pure Norway spruce (Picea abies Karst.) stand characteristics in experimental and control plots was developed using classification and regression tree statistical technique under endemic pest population density. The most significant variable in spruce bark beetle...
John E. Lundquist; Barbara J. Bentz
Over the past decade, native bark beetles (Coleoptera: Curculionidae) have killed billions of trees across millions of hectares of forest from Alaska to Mexico. Although bark beetle infestations are a regular force of natural change in forested ecosystems, several current outbreaks occurring simultaneously across western North America are the largest and most...
Robert A. Progar; Adris Eglitis; John E. Lundquist
Bark beetles are powerful agents of change in dynamic forest ecosystems. Most assessments of the effects of bark beetle outbreaks have been based on negative impacts on timber production. The positive effects of bark beetle activities are much less well understood. Bark beetles perform vital functions at all levels of scale in forest ecosystems. At the landscape...
Miller, Kirsten E; Hopkins, Kevin; Inward, Daegan J G; Vogler, Alfried P
Many species of fungi are closely allied with bark beetles, including many tree pathogens, but their species richness and patterns of distribution remain largely unknown. We established a protocol for metabarcoding of fungal communities directly from total genomic DNA extracted from individual beetles, showing that the ITS3/4 primer pair selectively amplifies the fungal ITS. Using three specimens of bark beetle from different species, we assess the fungal diversity associated with these specimens and the repeatability of these estimates in PCRs conducted with different primer tags. The combined replicates produced 727 fungal Operational Taxonomic Units (OTUs) for the specimen of Hylastes ater, 435 OTUs for Tomicus piniperda, and 294 OTUs for Trypodendron lineatum, while individual PCR reactions produced on average only 229, 54, and 31 OTUs for the three specimens, respectively. Yet, communities from PCR replicates were very similar in pairwise comparisons, in particular when considering species abundance, but differed greatly among the three beetle specimens. Different primer tags or the inclusion of amplicons in separate libraries did not impact the species composition. The ITS2 sequences were identified with the Lowest Common Ancestor approach and correspond to diverse lineages of fungi, including Ophiostomaceae and Leotiomycetes widely found to be tree pathogens. We conclude that Illumina MiSeq metabarcoding reliably captures fungal diversity associated with bark beetles, although numerous PCR replicates are recommended for an exhaustive sample. Direct PCR from beetle DNA extractions provides a rapid method for future surveys of fungal species diversity and their associations with bark beetles and environmental variables.
Křivan, Vlastimil; Lewis, Mark; Bentz, Barbara J; Bewick, Sharon; Lenhart, Suzanne M; Liebhold, Andrew
Tree-killing bark beetles are major disturbance agents affecting coniferous forest ecosystems. The role of environmental conditions on driving beetle outbreaks is becoming increasingly important as global climatic change alters environmental factors, such as drought stress, that, in turn, govern tree resistance. Furthermore, dynamics between beetles and trees are highly nonlinear, due to complex aggregation behaviors exhibited by beetles attacking trees. Models have a role to play in helping unravel the effects of variable tree resistance and beetle aggregation on bark beetle outbreaks. In this article we develop a new mathematical model for bark beetle outbreaks using an analogy with epidemiological models. Because the model operates on several distinct time scales, singular perturbation methods are used to simplify the model. The result is a dynamical system that tracks populations of uninfested and infested trees. A limiting case of the model is a discontinuous function of state variables, leading to solutions in the Filippov sense. The model assumes an extensive seed-bank so that tree recruitment is possible even if trees go extinct. Two scenarios are considered for immigration of new beetles. The first is a single tree stand with beetles immigrating from outside while the second considers two forest stands with beetle dispersal between them. For the seed-bank driven recruitment rate, when beetle immigration is low, the forest stand recovers to a beetle-free state. At high beetle immigration rates beetle populations approach an endemic equilibrium state. At intermediate immigration rates, the model predicts bistability as the forest can be in either of the two equilibrium states: a healthy forest, or a forest with an endemic beetle population. The model bistability leads to hysteresis. Interactions between two stands show how a less resistant stand of trees may provide an initial toe-hold for the invasion, which later leads to a regional beetle outbreak in the
Tittiger, Claus; Blomquist, Gary J
Pine bark beetles rely on aggregation pheromones to coordinate mass attacks and thus reproduce in host trees. The structural similarity between many pheromone components and those of defensive tree resin led to early suggestions that pheromone components are metabolic derivatives of ingested precursors. This model has given way to our current understanding that most pheromone components are synthesized de novo. Their synthesis involves enzymes that modify products from endogenous metabolic pathways; some of these enzymes have been identified and characterized. Pheromone production is regulated in a complex way involving multiple signals, including JH III. This brief review summarizes progress in our understanding of this highly specialized metabolic process. Copyright © 2017 Elsevier Inc. All rights reserved.
Macedo-Reis, Luiz Eduardo; Novais, Samuel Matos Antunes de; Monteiro, Graziela França; Flechtmann, Carlos Alberto Hector; Faria, Maurício Lopes de; Neves, Frederico de Siqueira
Bark and the ambrosia beetles dig into host plants and live most of their lives in concealed tunnels. We assessed beetle community dynamics in tropical dry forest sites in early, intermediate, and late successional stages, evaluating the influence of resource availability and seasonal variations in guild structure. We collected a total of 763 beetles from 23 species, including 14 bark beetle species, and 9 ambrosia beetle species. Local richness of bark and ambrosia beetles was estimated at 31 species. Bark and ambrosia composition was similar over the successional stages gradient, and beta diversity among sites was primarily determined by species turnover, mainly in the bark beetle community. Bark beetle richness and abundance were higher at intermediate stages; availability of wood was the main spatial mechanism. Climate factors were effectively non-seasonal. Ambrosia beetles were not influenced by successional stages, however the increase in wood resulted in increased abundance. We found higher richness at the end of the dry and wet seasons, and abundance increased with air moisture and decreased with higher temperatures and greater rainfall. In summary, bark beetle species accumulation was higher at sites with better wood production, while the needs of fungi (host and air moisture), resulted in a favorable conditions for species accumulation of ambrosia. The overall biological pattern among guilds differed from tropical rain forests, showing patterns similar to dry forest areas. © The Author 2016. Published by Oxford University Press on behalf of the Entomological Society of America.
Bjorn Okland; Andrew M. Liebhold; Ottar N. Bjornstad; Nadir Erbilgin; Paal Krokene; Paal Krokene
Comparisons of intraspecific spatial synchrony across multiple epidemic insect species can be useful for generating hypotheses about major determinants of population patterns at larger scales. The present study compares patterns of spatial synchrony in outbreaks of six epidemic bark beetle species in North America and Europe. Spatial synchrony among populations of the...
Richard W. Hofstetter; J. C. Moser; R. McGuire
Many species of mite that live exclusively in decaying wood and subcortical environments have intricate relationships with bark beetles (Coleoptera: Curculionidae, Scolytinae) (e.g., in the genus Dendroctonus, Ips, Scolytus) (Lindquist, 1969; Moser, 1975; Hirschmann and Wisniewski, 1983; Karg, 1993). These mites depend on bark beetles or other subcorticolous insects...
M. L. Gaylord; K. K. Williams; R. W. Hofstetter; J. D. McMillin; T. E. Degomez; M. R. Wagner
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...
Christopher Fettig; Jacek Hilszczański
Several species of bark beetles (Coleoptera: Curculionidae, Scolytinae) are capable of causing significant amounts of tree mortality in conifer forests throughout much of the world.Â In most cases, these events are part of the ecology of conifer forests and positively influence many ecological processes, but the economic and social implications can be...
Zhao, Tao; Axelsson, Karolin; Krokene, Paal; Borg-Karlson, Anna-Karin
Tree-killing bark beetles depend on aggregation pheromones to mass-attack their host trees and overwhelm their resistance. The beetles are always associated with phytopathogenic ophiostomatoid fungi that probably assist in breaking down tree resistance, but little is known about if or how much these fungal symbionts contribute to the beetles' aggregation behavior. In this study, we determined the ability of four major fungal symbionts of the spruce bark beetle Ips typographus to produce beetle aggregation pheromones. The fungi were incubated on Norway spruce Picea abies bark, malt agar, or malt agar amended with 0.5% (13)C glucose. Volatiles present in the headspace of each fungus were analyzed for 7 days after incubation using a SPME autosampler coupled to a GC/MS. Two Grosmannia species (G. penicillata and G. europhioides) produced large amounts of 2-methyl-3-buten-2-ol (MB), the major component in the beetles' aggregation pheromone blend, when growing on spruce bark or malt agar. Grosmannia europhioides also incorporated (13)C glucose into MB, demonstrating that the fungi can synthesize MB de novo using glucose as a carbon source. This is the first clear evidence that fungal symbionts of bark beetles can produce components in the aggregation pheromone blend of their beetle vectors. This provides new insight into the possible ecological roles of fungal symbionts in bark beetle systems and may deepen our understanding of species interactions and coevolution in these important biological systems.
Full Text Available Bark beetles and their fungal associates are integral parts of forest ecosystems, the European spruce bark beetle (Ips typographus Linnaeus, 1758 and the associated pathogenic blue stain fungus Ceratocystis polonica (SIEM. C. MOREAU, are the most devastating pests regarding Norway spruce [Picea abies (L. H. KARST.]. Bark beetles commonly inhabit weakened and felled trees as well as vital trees. They cause physiological disorders in trees by destroying a phloem and cambium or interrupt the transpiration -ow in the xylem. Conifers have a wide range of effective defence mechanisms that are based on the inner bark anatomy and physiological state of the tree. The basic function of bark defences is to protect the nutrient-and energy-rich phloem, the vital meristematic region of the vascular cambium, and the transpiration -ow in the sapwood. The main area of defence mechanisms is secondary phloem, which is physically and chemically protected by polyphenolic parenchyma (PP cells, sclerenchyma, calcium oxalate crystals and resin ducts. Conifer trunk pest resistance includes constitutive, inducible defences and acquired resistance. Both constitutive and inducible defences may deter beetle invasion, impede fungal growth and close entrance wounds. During a successful attack, systemic acquired resistance (SAR becomes effective and represents a third defence strategy. It gradually develops throughout the plant and provides a systemic change within the whole tree’s metabolism, which is maintained over a longer period of time. The broad range of defence mechanisms that contribute to the activation and utilisation of SAR, includes antioxidants and antioxidant enzymes, which are generally linked to the actions of reactive oxygen species (ROS. The presented review discusses the current knowledge on the antioxidant defence strategies of spruce inner bark against the bark beetle (Ips typographus and associated blue stain fungus (Ceratocystis polonica.
Křivan, Vlastimil; Lewis, M.; Bentz, B. J.; Bewick, S.; Lenhart, S. M.; Liebhold, A.
Roč. 407, OCT 21 (2016), s. 25-37 ISSN 0022-5193 Institutional support: RVO:60077344 Keywords : bistability * bark beetle * Dendroctonus ponderosae Subject RIV: EH - Ecology, Behaviour Impact factor: 2.113, year: 2016 http://www.sciencedirect.com/science/article/pii/S0022519316301928
Joel D. McMillin; Christopher J. Fettig
Native tree-killing bark beetles (Coleoptera: Curculionidae, Scolytinae) are a natural component of forest ecosystems. Eradication is neither possible nor desirable and periodic outbreaks will occur as long as susceptible forests and favorable climatic conditions co-exist. Recent changes in forest structure and tree composition by natural processes and management...
Gandhi, Kamal J K; Cognato, Anthony I; Lightle, Danielle M; Mosley, Bryson J; Nielsen, David G; Herms, Daniel A
In 2007, we surveyed the alien and endemic scolytine (bark and ambrosia beetles) fauna of northeastern Ohio, and for the most abundant species, we characterized their seasonal activity and response to three semiochemical baits. In total ,5,339 scolytine beetles represented by 47 species and 29 genera were caught in Lindgren funnel traps. Three species constituted 57% of the total catch, including Xylosandrus germanus (Blandford), Tomicus piniperda (L.), and Dryocoetes autographus (Ratzeburg). Of the total captured, 32% of the species and approximately 60% of the individuals were exotic, suggesting that exotic species numerically dominate the scolytine fauna in some urban areas. More native and exotic species were caught in traps baited with ethanol alone than in traps baited with other lures. However, significantly more individuals, especially of T. piniperda, D. autographus, Gnathotrichus materiarius (Fitch), and Ips grandicollis (Eichhoff), and species were caught in traps baited with ethanol plus alpha-pinene than in traps baited with ethanol alone or the exotic Ips lure. This suggests that among these baits, the ethanol plus alpha-pinene baits may be useful in maximizing scolytine beetle catches of these species within this region. Species diversity and richness for both native and exotic beetles was greatest in traps baited with ethanol alone. The period of peak trap capture varied depending upon species: X. germanus was most abundant in traps in mid-May and early-August; T. piniperda in mid-May; D. autographus in early June, mid-July, and mid-September; Anisandrus sayi Hopkins and G. materiarius in mid-May, mid-July, and early September; and I. grandicollis in early April, mid-July, and late September.
Milan Pernek; Boris Hrasovec; Dinka Matosevic; Ivan Pilas; Thomas Kirisits; John C. Moser
The species composition and abundance of phoretic mites of the bark beetles Pityokteines curvidens P. spinidens, and P. vorontzowi on Silver fir (Abies alba) were investigated in 2003 at two locations (Trakoscan and Litoric) in Croatia. Stem sections and...
J. P. Woodring; John C. Moser
The adult female and male plus the tritonymph of Histiostoma conjuncta (Woodring and Moser, 1970) (new comb.) and described. The species is known to be associated with various pine bark beetles from Honduras, Guatemala, and Louisiana.
Jaramillo, Juliana; Torto, Baldwyn; Mwenda, Dickson; Troeger, Armin; Borgemeister, Christian; Poehling, Hans-Michael; Francke, Wittko
Unanswered key questions in bark beetle-plant interactions concern host finding in species attacking angiosperms in tropical zones and whether management strategies based on chemical signaling used for their conifer-attacking temperate relatives may also be applied in the tropics. We hypothesized that there should be a common link in chemical signaling mediating host location by these Scolytids. Using laboratory behavioral assays and chemical analysis we demonstrate that the yellow-orange exocarp stage of coffee berries, which attracts the coffee berry borer, releases relatively high amounts of volatiles including conophthorin, chalcogran, frontalin and sulcatone that are typically associated with Scolytinae chemical ecology. The green stage of the berry produces a much less complex bouquet containing small amounts of conophthorin but no other compounds known as bark beetle semiochemicals. In behavioral assays, the coffee berry borer was attracted to the spiroacetals conophthorin and chalcogran, but avoided the monoterpenes verbenone and α-pinene, demonstrating that, as in their conifer-attacking relatives in temperate zones, the use of host and non-host volatiles is also critical in host finding by tropical species. We speculate that microorganisms formed a common basis for the establishment of crucial chemical signals comprising inter- and intraspecific communication systems in both temperate- and tropical-occurring bark beetles attacking gymnosperms and angiosperms.
Full Text Available Unanswered key questions in bark beetle-plant interactions concern host finding in species attacking angiosperms in tropical zones and whether management strategies based on chemical signaling used for their conifer-attacking temperate relatives may also be applied in the tropics. We hypothesized that there should be a common link in chemical signaling mediating host location by these Scolytids. Using laboratory behavioral assays and chemical analysis we demonstrate that the yellow-orange exocarp stage of coffee berries, which attracts the coffee berry borer, releases relatively high amounts of volatiles including conophthorin, chalcogran, frontalin and sulcatone that are typically associated with Scolytinae chemical ecology. The green stage of the berry produces a much less complex bouquet containing small amounts of conophthorin but no other compounds known as bark beetle semiochemicals. In behavioral assays, the coffee berry borer was attracted to the spiroacetals conophthorin and chalcogran, but avoided the monoterpenes verbenone and α-pinene, demonstrating that, as in their conifer-attacking relatives in temperate zones, the use of host and non-host volatiles is also critical in host finding by tropical species. We speculate that microorganisms formed a common basis for the establishment of crucial chemical signals comprising inter- and intraspecific communication systems in both temperate- and tropical-occurring bark beetles attacking gymnosperms and angiosperms.
Bentz, Barbara; Logan, Jesse; MacMahon, James A.; Allen, Craig D.; Ayres, Matt; Berg, Edward E; Carroll, Allan; Hansen, Matt; Hicke, Jeff H.; Joyce, Linda A.; Macfarlane, Wallace; Munson, Steve; Negron, Jose; Paine, Tim; Powell, Jim; Raffa, Kenneth; Regniere, Jacques; Reid, Mary; Romme, Bill; Seybold, Steven J.; Six, Diana; Vandygriff, Jim; Veblen, Tom; White, Mike; Witcosky, Jeff; Wood, David
Since 1990, native bark beetles have killed billions of trees across millions of acres of forest from Alaska to northern Mexico. Although bark beetle infestations are a regular force of natural change in forested ecosystems, several of the current outbreaks, which are occurring simultaneously across western North America, are the largest and most severe in recorded history.
Kier D. Klepzig; D.L. Six
Recent thinking in symbiosis research has emphasized a holistic consideration of these complex interactions. Bark beetles and their associated microbes are one group which has previously not been addressed in this manner. We review the study of symbiotic interactions among bark beetles and microbes in light of this thinking. We describe the considerable progress...
If not the most destructive forest pest, bark beetles are probably a close second in their culpability for killing millions of trees in the Northern Hemisphere. This volume provides an aptly-timed interdisciplinary review on aspects of bark beetle physiology, especially how it relates to selecting, ...
Ghimire, Rajendra P.; Kivimäenpää, Minna; Blomqvist, Minna; Holopainen, Toini; Lyytikäinen-Saarenmaa, Päivi; Holopainen, Jarmo K.
Climate warming driven storms are evident causes for an outbreak of the European spruce bark beetle (Ips typographus L.) resulting in the serious destruction of mature Norway spruce (Picea abies Karst.) forests in northern Europe. Conifer species are major sources of biogenic volatile organic compounds (BVOCs) in the boreal zone. Climate relevant BVOC emissions are expected to increase when conifer trees defend against bark beetle attack by monoterpene (MT)-rich resin flow. In this study, BVOC emission rates from the bark surface of beetle-attacked and non-attacked spruce trees were measured from two outbreak areas, Iitti and Lahti in southern Finland, and from one control site at Kuopio in central Finland. Beetle attack increased emissions of total MTs 20-fold at Iitti compared to Kuopio, but decreased the emissions of several sesquiterpenes (SQTs) at Iitti. At the Lahti site, the emission rate of α-pinene was positively correlated with mean trap catch of bark beetles. The responsive individual MTs were tricyclene, α-pinene, camphene, myrcene, limonene, 1,8-cineole and bornyl acetate in both of the outbreak areas. Our results suggest that bark beetle outbreaks affect local BVOC emissions from conifer forests dominated by Norway spruce. Therefore, the impacts of insect outbreaks are worth of consideration to global BVOC emission models.
Rassati, Davide; Faccoli, Massimo; Haack, Robert A; Rabaglia, Robert J; Petrucco Toffolo, Edoardo; Battisti, Andrea; Marini, Lorenzo
Non-native bark and ambrosia beetles represent a threat to forests worldwide. Their invasion patterns are, however, still unclear. Here we investigated first, if the spread of non-native bark and ambrosia beetles is a gradual or a discontinuous process; second, which are the main correlates of their community structure; third, whether those correlates correspond to those of native species. We used data on species distribution of non-native and native scolytines in the continental 48 USA states. These data were analyzed through a beta-diversity index, partitioned into species richness differences and species replacement, using Mantel correlograms and non-metric multidimensional scaling (NMDS) ordination for identifying spatial patterns, and regression on distance matrices to test the association of climate (temperature, rainfall), forest (cover area, composition), geographical (distance), and human-related (import) variables with β-diversity components. For both non-native bark and ambrosia beetles, β-diversity was mainly composed of species richness difference than species replacement. For non-native bark beetles, a discontinuous invasion process composed of long distance jumps or multiple introduction events was apparent. Species richness differences were primarily correlated with differences in import values while temperature was the main correlate of species replacement. For non-native ambrosia beetles, a more continuous invasion process was apparent, with the pool of non-native species arriving in the coastal areas that tended to be filtered as they spread to interior portions of the continental USA. Species richness differences were mainly correlated with differences in rainfall among states, while rainfall and temperature were the main correlates of species replacement. Our study suggests that the different ecology of bark and ambrosia beetles influences their invasion process in new environments. The lower dependency that bark beetles have on climate
Full Text Available Non-native bark and ambrosia beetles represent a threat to forests worldwide. Their invasion patterns are, however, still unclear. Here we investigated first, if the spread of non-native bark and ambrosia beetles is a gradual or a discontinuous process; second, which are the main correlates of their community structure; third, whether those correlates correspond to those of native species. We used data on species distribution of non-native and native scolytines in the continental 48 USA states. These data were analyzed through a beta-diversity index, partitioned into species richness differences and species replacement, using Mantel correlograms and non-metric multidimensional scaling (NMDS ordination for identifying spatial patterns, and regression on distance matrices to test the association of climate (temperature, rainfall, forest (cover area, composition, geographical (distance, and human-related (import variables with β-diversity components. For both non-native bark and ambrosia beetles, β-diversity was mainly composed of species richness difference than species replacement. For non-native bark beetles, a discontinuous invasion process composed of long distance jumps or multiple introduction events was apparent. Species richness differences were primarily correlated with differences in import values while temperature was the main correlate of species replacement. For non-native ambrosia beetles, a more continuous invasion process was apparent, with the pool of non-native species arriving in the coastal areas that tended to be filtered as they spread to interior portions of the continental USA. Species richness differences were mainly correlated with differences in rainfall among states, while rainfall and temperature were the main correlates of species replacement. Our study suggests that the different ecology of bark and ambrosia beetles influences their invasion process in new environments. The lower dependency that bark beetles have
Christopher J. Fettig; Donald M. Grosman; A. Steven. Munson
Bark beetles (Coleoptera: Curculionidae, Scolytinae) cause extensive tree mortality in coniferous forests of the western U.S., and play an important role in the disturbance ecology of these systems. Recently, significant outbreaks of several bark beetle species have occurred from Alaska to New Mexico heightening public awareness of the issue and, in many cases, the...
Patricia L. Johnson; Jane L. Hayes; John E. Rinehart; Walter S. Sheppard
Scolytus schevyrewi Semenov, the banded elm bark beetle, and S. multistriatus Marsham, the smaller European elm bark beetle, are morphologically similar. Reliance on adult external morphological characters for identification can be problematic because of wide within species variability and the need for good-quality specimens....
Robert J. Cain; Jane L. Hayes
The recent dramatic impacts of bark beetle outbreaks across conifer forests of the West have been mapped and reported by entomology and pathology professionals with Forest Health Protection (FHP), a component of USDA Forest Service's State and Private Forestry, and their state counterparts. These forest conditions set the stage for the formation of the Western...
Skelton, James; Jusino, Michelle A; Li, You; Bateman, Craig; Thai, Pham Hong; Wu, Chengxu; Lindner, Daniel L; Hulcr, Jiri
Separating symbioses from incidental associations is a major obstacle in symbiosis research. In this survey of fungi associated with Asian bark and ambrosia beetles, we used quantitative culture and DNA barcode identification to characterize fungal communities associated with co-infesting beetle species in pines (Pinus) of China and Vietnam. To quantitatively discern likely symbioses from coincidental associations, we used multivariate analysis and multilevel pattern analysis (a type of indicator species analysis). Nearly half of the variation in fungal community composition in beetle galleries and on beetle bodies was explained by beetle species. We inferred a spectrum of ecological strategies among beetle-associated fungi: from generalist multispecies associates to highly specialized single-host symbionts that were consistently dominant within the mycangia of their hosts. Statistically significant fungal associates of ambrosia beetles were typically only found with one beetle species. In contrast, bark beetle-associated fungi were often associated with multiple beetle species. Ambrosia beetles and their galleries were frequently colonized by low-prevalence ambrosia fungi, suggesting that facultative ambrosial associations are commonplace, and ecological mechanisms such as specialization and competition may be important in these dynamic associations. The approach used here could effectively delimit symbiotic interactions in any system where symbioses are obscured by frequent incidental associations. It has multiple advantages including (1) powerful statistical tests for non-random associations among potential symbionts, (2) simultaneous evaluation of multiple co-occurring host and symbiont associations, and (3) identifying symbionts that are significantly associated with multiple host species.
Therese M. Poland; John H. Borden
The bark beetle predator Thanasimus undatulus Say was captured in statistically significant numbers (total catch = 470, 713, and 137) in three field experiments using multiple-funnel traps baited with various combinations of pheromones for the spruce beetle, Dendroctonus rufipennis Kirby, and the secondary bark beetles ...
Dohet, Loïc; Grégoire, Jean-Claude; Berasategui, Aileen; Kaltenpoth, Martin; Biedermann, Peter H W
Bark beetles (Curculionidae: Scolytinae) are one of the most species-rich herbivorous insect groups with many shifts in ecology and host-plant use, which may be mediated by their bacterial and fungal symbionts. While symbionts are well studied in economically important, tree-killing species, little is known about parasitic species whose broods develop in living trees. Here, using culture-dependent and independent methods, we provide a comprehensive overview of the associated bacteria, yeasts and filamentous fungi of the parasitic Dendroctonus micans, D. punctatus and D. valens, and compare them to those of other tree-inhabiting insects. Despite inhabiting different geographical regions and/or host trees, the three species showed similar microbial communities. Enterobacteria were the most prevalent bacteria, in particular Rahnella, Pantoea and Ewingella, in addition to Streptomyces Likewise, the yeasts Candida/Cyberlindnera were the most prominent fungi. All these microorganisms are widespread among tree-inhabiting insects with various ecologies, but their high prevalence overall might indicate a beneficial role such as detoxification of tree defenses, diet supplementation or protection against pathogens. As such, our results enable comparisons of symbiont communities of parasitic bark beetles with those of other beetles, and will contribute to our understanding of how microbial symbioses facilitate dietary shifts in insects. © FEMS 2016. All rights reserved. For permissions, please e-mail: email@example.com.
Popa, Valentin; Déziel, Eric; Lavallée, Robert; Bauce, Eric; Guertin, Claude
Bark beetles, especially Dendroctonus species, are considered to be serious pests of the coniferous forests in North America. Bark beetle forest pests undergo population eruptions, causing region wide economic losses. In order to save forests, finding new and innovative environmentally friendly approaches in wood-boring insect pest management is more important than ever. Several biological control methods have been attempted over time to limit the damage and spreading of bark beetle epidemics. The use of entomopathogenic microorganisms against bark beetle populations is an attractive alternative tool for many biological control programmes in forestry. However, the effectiveness of these biological control agents is strongly affected by environmental factors, as well as by the susceptibility of the insect host. Bark beetle susceptibility to entomopathogens varies greatly between species. According to recent literature, bark beetles are engaged in symbiotic relationships with fungi and bacteria. These types of relationship are very complex and apparently involved in bark beetle defensive mechanisms against pathogens. The latest scientific discoveries in multipartite symbiosis have unravelled unexpected opportunities in bark beetle pest management, which are discussed in this article. Copyright © 2012 Society of Chemical Industry.
Grodzki, Wojciech; McManus, Michael; Knizek, Milos; Meshkova, Valentina; Mihalciuc, Vasile; Novotny, Julius; Turcani, Marek; Slobodyan, Yaroslav
The spruce bark beetle, Ips typographus (L.) is the most serious pest of mature spruce stands, mainly Norway spruce, Picea abies (L.) Karst. throughout Eurasia. A complex of weather-related events and other environmental stresses are reported to predispose spruce stands to bark beetle attack and subsequent tree mortality; however the possible role of industrial pollution as a predisposing factor to attack by this species is poorly understood. The abundance and dynamics of I. typographus populations was evaluated in 60-80 year old Norway spruce stands occurring on 10x50 ha sites in five countries within the Carpathian range that were selected in proximity to established ozone measurement sites. Data were recorded on several parameters including the volume of infested trees, captures of adult beetles in pheromone traps, number of attacks, and the presence and relative abundance of associated bark beetle species. In several cases, stands adjacent to sites with higher ozone values were associated with higher bark beetle populations. The volume of sanitary cuttings, a reflection of tree mortality, and the mean daily capture of beetles in pheromone traps were significantly higher at sites where the O 3 level was higher. However, the mean infestation density on trees was higher in plots associated with lower O 3 levels. Captures of beetles in pheromone traps and infestation densities were higher in the zone above 800 m. However, none of the relationships was conclusive, suggesting that spruce bark beetle dynamics are driven by a complex interaction of biotic and abiotic factors and not by a single parameter such as air pollution. - Air pollution (ozone) can be one of predisposing factors that increases the susceptibility of mountain Norway spruce stands to attack by Ips typographus and associated bark beetle species
Full Text Available Aside from the ecological impacts, invasive species fascinate ecologists because of the unique opportunities that invasives offer in the study of community ecology. Some hypotheses have been proposed to illustrate the mechanisms that allow exotics to become invasive. However, positive interactions between exotic and native insects are rarely utilized to explain invasiveness of pests.Here, we present information on a recently formed association between a native and an exotic bark beetle on their shared host, Pinus tabuliformis, in China. In field examinations, we found that 35-40% of P. tabuliformis attacked by an exotic bark beetle, Dendroctonus valens, were also attacked by a native pine bark beetle, Hylastes parallelus. In the laboratory, we found that the antennal and walking responses of H. parallelus to host- and beetle-produced compounds were similar to those of the exotic D. valens in China. In addition, D. valens was attracted to volatiles produced by the native H. parallelus.We report, for the first time, facilitation between an exotic and a native bark beetle seems to involve overlap in the use of host attractants and pheromones, which is cross-attraction. The concept of this interspecific facilitation could be explored as a novel invasive mechanism which helps explain invasiveness of not only exotic bark beetles but also other introduced pests in principle. The results reported here also have particularly important implications for risk assessments and management strategies for invasive species.
Zander R. Human
Full Text Available Actinomycete bacteria are often associated with insects that have a mutualistic association with fungi. These bacteria are believed to be important to this insect–fungus association as they produce antibiotics that exclude other saprophytic fungi from the immediate environment. The aim of this study was to investigate the presence of potentially protective actinomycetes associated with Orthotomicus erosus, an alien invasive pine bark beetle, in South Africa. This bark beetle and its relatives have an association with Ophiostomatales species which are often the only fungi found in the bark beetle galleries. We hypothesised that antibiotic-producing actinomycetes could be responsible for the paucity of other fungi in the galleries by producing compounds to which the Ophiostoma spp. are tolerant. Several actinomycetes in the genus Streptomyces and one Gordonia sp. were isolated from the beetle. Interestingly, most isolates were from the same species as actinomycetes associated with other pine-infesting insects from other parts of the world, including bark beetles and the woodwasp Sirex noctilio. Most actinomycetes isolated had strong antifungal properties against the selected test fungi, including Ophiostoma ips, which is the most common fungal symbiont of Orthotomicus erosus. Although the actinomycetes did not benefit Ophiostoma ips and the hypothesis was not supported, their sporadic association with Orthotomicus erosus suggests that they could have some impact on the composition of the fungal communities present in the bark beetle galleries, which is at present poorly understood.
Miller, Daniel R; Rabaglia, Robert J
In 2002-2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (-)-alpha-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25-28 degrees C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (-)-alpha-pinene lures (release rate, 2-6 g/day at 25-28 degrees C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (-)-alpha-pinene in some locations. (-)-alpha-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70-97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (-)-alpha-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.
Chen, H; Tang, M
Spatial and temporal dynamics of bark beetles in single tree trunks of Pinus armandi were studied in Qinling Mountains, Shaanxi Province, China. Ten species of engraver bark beetles attacked from healthy to withered Chinese white pines, but seven species were commonly detected every year in Qinling forest ecosystem. Dendroctonus armandi and Hylurgops longipilis were common species at the lower of trunks, and Ips acuminatus, Polygraphus sinensis, and Pityogenes japonicus primary distributed in the middle of trunks, whereas population densities of Cryphalus lipingensis and C. chinlingensis centralized at the upper trunks and branches of Chinese white pines. On the time series, D. armandi, as a dominant species in Chinese white pines of Qinling forest ecosystem, mainly attacked healthy and weakened trees and cooperated with blue stain fungus that resulted in the declining abruptly resistance and triggered the secondary bark beetles to attack the infected or withered host trees. Attacking and colonizing phenology of bark beetles in Qinling forest ecosystem are caused by complex interactions among spatial and trophic competition and cooperation and exhibit particular spatial and temporal patterns. Our results support the view that competition and cooperation within bark beetles are a critical factor to influence bark beetles spatial and temporal distribution, and stability of bark beetles' ecosystem, D. armandi, I. acuminatus, P. japonicus, P. sinensis, C. lipingensis, C. chinlingensis, and H. longipilis in Chinese white pine of Qinling forest ecosystem.
Linnakoski, Riikka; de Beer, Z Wilhelm; Niemelä, Pekka; Wingfield, Michael J
Bark beetles (Coleoptera, Scolytinae) have a widespread association with fungi, especially with ophiostomatoid fungi (Ascomycota) that cause blue staining of wood, and in some cases, serious tree diseases. In Fennoscandia, most studies of these fungi have focused on economically important bark beetle species and this is likely to have led to a biased view of the fungal biodiversity in the region. Recently, the associations between fungi and bark beetles in Fennoscandia have been shown to be more diverse than previously thought. Furthermore, they form complex and dynamic associations that are only now beginning to emerge. This review examines the current knowledge of the rather poorly known interactions between bark beetles, fungi and their conifer host trees in Fennoscandia. The diversity of ophiostomatoid species is discussed and the possible factors that influence the assemblages of fungal associates are considered for all species that are known to occur in the region. For many ophiostomatoid species found in Fennoscandia, little or nothing is known regarding their pathogenicity, particularly if they were to be transferred to new environments. We, therefore, draw attention to the possible threats of timber trade and climate change-induced invasions of new habitats by bark beetles and the fungi that can be moved along with them.
Michael J. Wingfield
Full Text Available Bark beetles (Coleoptera, Scolytinae have a widespread association with fungi, especially with ophiostomatoid fungi (Ascomycota that cause blue staining of wood, and in some cases, serious tree diseases. In Fennoscandia, most studies of these fungi have focused on economically important bark beetle species and this is likely to have led to a biased view of the fungal biodiversity in the region. Recently, the associations between fungi and bark beetles in Fennoscandia have been shown to be more diverse than previously thought. Furthermore, they form complex and dynamic associations that are only now beginning to emerge. This review examines the current knowledge of the rather poorly known interactions between bark beetles, fungi and their conifer host trees in Fennoscandia. The diversity of ophiostomatoid species is discussed and the possible factors that influence the assemblages of fungal associates are considered for all species that are known to occur in the region. For many ophiostomatoid species found in Fennoscandia, little or nothing is known regarding their pathogenicity, particularly if they were to be transferred to new environments. We, therefore, draw attention to the possible threats of timber trade and climate change-induced invasions of new habitats by bark beetles and the fungi that can be moved along with them.
Discusses the aggregation pheromone of the smaller European elm bark beetle, Scolytus multistriatus (Marsham), with emphasis on information that could be used in the classroom as a practical application of organic chemistry. (Author/GA)
Robert A. Haack; Robert J. Rabaglia
Bark and ambrosia beetles (Coleoptera: Curculionidae: Scolytinae) are among the most important insects affecting trees and forests worldwide. There are approximately 6000 scolytine species worldwide, with species found on all continents except Antarctica (Table 3.1) (Wood and Bright, 1992; Bright and Skidmore, 1997, 2002; Wood, 2007). The majority of species are found...
Jeffrey A Hicke; Morris C. Johnson; Jane L. Hayes; Haiganoush K. Preisler
Millions of trees killed by bark beetles in western North America have raised concerns about subsequent wildfire, but studies have reported a range of conclusions, often seemingly contradictory, about effects on fuels and wildfire. In this study, we reviewed and synthesized the published literature on modifications to fuels and fire characteristics following beetle-...
Grosman, Donald M; Clarke, Stephen R; Upton, William W
We evaluated the efficacy of systemic insecticides emamectin benzoate and fipronil for preventing mortality of individual loblolly pines, Pinus taeda L., as a result of attacks by southern pine bark beetles (Coleoptera: Curculionidae, Scolytinae) for two consecutive years in Mississippi (2005-2006) and Alabama (2006-2007). Trees were injected once in the spring of 2005 (Mississippi) or 2006 (Alabama) and then were baited with species-specific bark beetle lures several weeks later. The southern pine beetle, Dendroctonus frontalis Zimmermann, was the target species but was changed to Ips spp. in Mississippi (but not Alabama) the second year because of few southern pine beetle attacks on baited trees. Single injections of emamectin benzoate were effective in reducing tree mortality caused by bark beetles compared with untreated checks. Although less effective overall, fipronil also significantly reduced tree mortality from southern pine beetle compared with the checks during the second year in Alabama. Tree mortality continued well after the lures had been removed. Evaluations of bolts taken from experimental trees killed in 2006 indicated that emamectin benzoate effectively prevented parent bark beetle gallery construction and that fipronil significantly reduced lengths of galleries constructed by adult beetles, brood development, and emergence, compared with checks. In contrast, neither insecticide treatment prevented the bark beetles from inoculating blue stain fungi, Ophiostoma spp., into treated trees.
A.J. Walter; R.C. Venette; S.A. Kells
To predict whether an herbivorous pest insect will establish in a new area, the potential host plants must be known. For invading bark beetles, adults must recognize and accept trees suitable for larval development. The preference-performance hypothesis predicts that adults will select host species that maximize the fitness of their offspring. We tested five species of...
K. J. Dodds; D. W. Gilmore; S. J. Seybold
The Douglas-fir beetle, Dendroctonus pseudotsugae Hopkins, was detected in 2001 in northern Minnesota outside its natural range and the range of its native hosts, Douglas-fir, Pseudotsuga menziesii (Mirbel) Franco, and western larch, Larix occidentalis Nutt. Consecutive years of...
Hood, S.; Sala, A.
Wildfire and bark beetles are the two largest disturbance agents in North American conifer forests and have interacted for millennia to drive forest composition, structure, and ecological processes. Recent widespread mortality in western coniferous forests due to bark beetle outbreaks have been attributed in part to increasing temperatures and drought associated with global climate change. In fire-dependent forests, fire exclusion has also led to uncharacteristically dense forests which are also thought to be more susceptible to bark beetle outbreaks due to increased drought stress in individual trees. These mortality events have spurred strong interest in the interaction of fire and bark beetles in driving forest dynamics under a changing climate. However, a fact that has not received adequate attention is whether fire exclusion in fire-dependent forests decreases allocation to tree defense, thereby making contemporary forests more prone to bark beetle outbreaks, regardless of climate and stand structure. Fire is known to increase constitutive resin production in many tree species, yet the impact of frequent fire on expression of better defended tree phenotypes has never been examined. We hypothesized that frequent, low-intensity fire increases tree resistance to bark beetle attack through systemic induced resistance. Using a combination of sampling in natural stands for which we had long-term fire history data and an experimental block design of four thinning and burning treatments, we examined the influence of fire and water stress on tree defense to determine if frequent fire increases tree defense and the degree to which water stress modulates this response. We used axial resin ducts as the measure of defense, as this is where resin is both stored and manufactured in Pinaceae. Resin duct production and density has also been shown to be a better indicator of mortality from bark beetle attacks than tree growth. Resin duct density increased after fire at all
Daniel R. West; Elisa J. Bernklau; Louis B. Bjostad; William R. Jacobi
Conifer defenses against bark beetle attack include, but are not limited to, quantitative and qualitative defenses produced prior to attack. Our objective was to assess host defenses of lodgepole pine and ponderosa pine from ecotone stands. These stands provide a transition of host species for mountain pine beetle (Dendroctonus ponderosae; MPB). We asked two questions: (1) do the preformed quantitative host defenses (amount of resin) and (2) the preformed qualitative host defenses (monoterpen...
Carolyn H. Sieg; Rodman R. Linn; Francois Pimont; Chad M. Hoffman; Joel D. McMillin; Judith Winterkamp; L. Scott Baggett
Previous studies have suggested that bark beetles and fires can be interacting disturbances, whereby bark beetle-caused tree mortality can alter the risk and severity of subsequent wildland fires. However, there remains considerable uncertainty around the type and magnitude of the interaction between fires following bark beetle attacks, especially in drier forest types...
Brownbridge, Michael; Reay, Stephen D; Cummings, Nicholas J
Hylastes ater and Hylurgus ligniperda are introduced pests of re-established Pinus radiata in New Zealand. Both species breed under the bark of stumps in recently harvested areas. Adult maturation feeding on pine seedlings planted in adjacent areas can significantly impact seedling growth, and in severe cases seedlings will die. Entomopathogenic fungi are important natural mortality factors in bark beetle populations, and Beauveria spp. are predominant. Here, we report on the isolation of other fungal species from H. ater in New Zealand. Based on morphological characteristics and sequencing data, two species, Metarhizium flavoviride var. pemphigi and Hirsutella guignardii, were recovered from H. ater. Both are new records for New Zealand and appear to be the first records of these species from bark beetles worldwide.
Jared W. Westbrook; Marcio F. R. Resende Jr.; Patricio Munoz; Alejandro R. Walker; Jill L. Wegrzyn; C. Dana Nelson; David B. Neale; Matias Kirst; Salvador A. Gezan; Gary F. Peter; John M. Davis
In the last decade, outbreaks of bark beetles in coniferous forests of North America have caused unprecedented tree mortality and economic losses (Nowak et al., 2008; van Mantgem et al., 2009; Waring et al., 2009), converting forests that were previously atmospheric carbon sinks into carbon sources (Kurz et al., 2008). Native species of bark beetle rapidly kill healthy...
Christopher J. Hayes; Tom E. DeGomez; Karen M. Clancy; Kelly K. Williams; Joel D. McMillin; John A. Anhold
Lindgren funnel traps baited with aggregation pheromones are widely used to monitor and manage populations of economically important bark beetles (Coleoptera: Scolytidae). This study was designed to advance our understanding of how funnel trap catches assess bark beetle communities and relative abundance of individual species. In the second year (2005) of a 3-yr study...
The bark beetles Pityogenes bidentatus and P. quadridens (Coleoptera, Curculionidae, Scolytinae) compete for bark areas on branches of Scotch pine, Pinus sylvestris. Hindguts and head/thoraxes of males and females of both species feeding in hosts were extracted in pentane and analyzed by gas chromat...
Meurisse, Nicolas; Pawson, Stephen
Long distance dispersal to locate suitable breeding sites is recognized as a key trait influencing the population dynamics and distribution of bark beetles and other saprophytic insects. While dispersal behavior has been studied for a range of aggressive 'tree killing' bark beetles, few have considered the dispersal behaviour of non-aggressive saprophytic bark beetles that utilize kairomones (host volatiles). We present the results of a mark-recapture experiment that examined adult dispersal patterns of the saprophytic bark beetle Hylurgus ligniperda. Releases took place in summer and autumn 2014, in a clearcut pine forest in the central North Island, New Zealand. Both flight-experienced and flight-naïve adults were marked and released in the center of a circular trap grid that extended to 960 m with 170 or 200 panel traps baited with a kairomone blend of alpha-pinene and ethanol. Of the 18,464 released H. ligniperda, 9,209 (49.9%) of the beetles flew, and 96 (1.04%) of the beetles that flew were recaptured. Individuals were recaptured at all distances. The recapture of flight-experienced beetles declined with dispersal distance, and a diffusion model showed heterogeneous dispersal tendencies within the population. Our best model estimated that 46% of flight-experienced beetles disperse > 1 km, and 1.6% > 5 km. Conversely, no declining pattern was shown in the recapture of flight-naïve beetles, suggesting that emerging H. ligniperda may require a period of flight to initiate chemotropic orientation behavior and subsequent attraction to traps. We discuss the implications of these findings for the management of phytosanitary risks. For instance, combining landscape knowledge of source populations with dispersal processes facilitates estimation of pest pressure at economically sensitive areas such as harvest and timber storage sites. Quantitative dispersal estimates also inform pest risk assessments by predicting spread rates for H. ligniperda that has proven
Full Text Available Long distance dispersal to locate suitable breeding sites is recognized as a key trait influencing the population dynamics and distribution of bark beetles and other saprophytic insects. While dispersal behavior has been studied for a range of aggressive 'tree killing' bark beetles, few have considered the dispersal behaviour of non-aggressive saprophytic bark beetles that utilize kairomones (host volatiles. We present the results of a mark-recapture experiment that examined adult dispersal patterns of the saprophytic bark beetle Hylurgus ligniperda. Releases took place in summer and autumn 2014, in a clearcut pine forest in the central North Island, New Zealand. Both flight-experienced and flight-naïve adults were marked and released in the center of a circular trap grid that extended to 960 m with 170 or 200 panel traps baited with a kairomone blend of alpha-pinene and ethanol. Of the 18,464 released H. ligniperda, 9,209 (49.9% of the beetles flew, and 96 (1.04% of the beetles that flew were recaptured. Individuals were recaptured at all distances. The recapture of flight-experienced beetles declined with dispersal distance, and a diffusion model showed heterogeneous dispersal tendencies within the population. Our best model estimated that 46% of flight-experienced beetles disperse > 1 km, and 1.6% > 5 km. Conversely, no declining pattern was shown in the recapture of flight-naïve beetles, suggesting that emerging H. ligniperda may require a period of flight to initiate chemotropic orientation behavior and subsequent attraction to traps. We discuss the implications of these findings for the management of phytosanitary risks. For instance, combining landscape knowledge of source populations with dispersal processes facilitates estimation of pest pressure at economically sensitive areas such as harvest and timber storage sites. Quantitative dispersal estimates also inform pest risk assessments by predicting spread rates for H. ligniperda that
Thousand cankers disease is caused by plant pathogenic Geosmithia morbida Kolarík, Freeland, Utley, and Tisserat; a fungus vectored primarily by the walnut twig beetle, Pityophthorus juglandis (Blackman). The role of other bark and ambrosia beetle species in persistence and spread of this disease r...
D. R. Miller; R. J. Rabaglia
In 2002â2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (â)-Î±-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South...
Christopher J. Fettig
Several species of bark beetles (Coleoptera: Curculionidae, Scolytinae), and to a much lesser extent wood borers (primarily Coleoptera: Buprestidae and Cerambycidae), are capable of causing conifer mortality in Mediterranean forests of California, U.S. This mortality is an important part of the ecology of these ecosystems, but the economic and social...
Bark beetles (Coleoptera: Scolytidae), especially pests in the genera Dendroctonus, Ips, Scolytus, Trypodendron, Tomicus, and Pityogenes of the Northern hemisphere are reviewed regarding aspects of their chemical ecology during host finding and selection. Most of the species covered here feed on con...
Daniel R. Miller; Robert J. Rabaglia
In 2002â2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (?)-?-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with...
A write-up for the Elsevier SciTech Connect blog on the recently published book entitled "Bark Beetles: Biology and Ecology of Native and Invasive Species," edited by Fernando E. Vega and Richard W. Hofstetter. The book was published by Academic Press in January 2015....
Ferrenberg, Scott; Kane, Jeffrey M; Mitton, Jeffry B
Bark beetles have recently killed billions of trees, yet conifer defenses are formidable and some trees resist attack. A primary anti-insect defense of pines is oleoresin from a system of resin ducts throughout the tree. Resin defense traits are heritable, and evidence suggests that resin duct characteristics are associated with resistance to insects. However, comparisons of resin ducts in trees killed by bark beetles to trees that resisted attack are unavailable. We compared vertical resin duct characteristics (number, density, and size) and growth rates from trees that were "resistant" (survived mass attack) versus "susceptible" (killed by attack) to bark beetles in lodgepole (Pinus contorta) and limber (Pinus flexilis) pines. Resistant trees of both species had significantly more resin ducts in recent growth than susceptible trees. Discriminant analysis (DA) correctly categorized 84% of lodgepole and 92% of limber pines as susceptible/resistant based on combinations of resin duct and growth characteristics from recent 5- through 20-year growth intervals. DA models using measures from only the most recent 5 years of growth correctly categorized 72 and 81% of lodgepole and limber pines, respectively. Comparing resistant to susceptible trees independent of species identity led to the correct categorization of 82% of trees based on factors from 5- to 20-year intervals, and 73% of trees using only resin duct counts from the most recent 5 years. We conclude that resin duct characteristics can be used to assess tree resistance to bark beetles across pine species, and offer a metric for management to enhance pest resistance.
Kolařík, Miroslav; Hulcr, Jiri; Tisserat, Ned; De Beer, Wilhelm; Kostovčík, Martin; Kolaříková, Zuzana; Seybold, Steven J; Rizzo, David M
Fungi in the genus Geosmithia (Ascomycota: Hypocreales) are frequent associates of bark beetles and woodborers that colonize hardwood and coniferous trees. One species, Geosmithia morbida, is an economically damaging invasive species. The authors surveyed the Geosmithia species of California and Colorado, USA, to (i) provide baseline data on taxonomy of Geosmithia and beetle vector specificity across the western USA; (ii) investigate the subcortical beetle fauna for alternative vectors of the invasive G. morbida; and (iii) interpret the community composition of this region within the emerging global biogeography of Geosmithia. Geosmithia was detected in 87% of 126 beetle samples obtained from 39 plant species. Twenty-nine species of Geosmithia were distinguished, of which 13 may be new species. Bark beetles from hardwoods, Cupressus, and Sequoia appear to be regular vectors, with Geosmithia present in all beetle gallery systems examined. Other subcortical insects appear to vector Geosmithia at lower frequencies. Overall, most Geosmithia have a distinct level of vector specificity (mostly high, sometimes low) enabling their separation to generalists and specialists. Plant pathogenic Geosmithia morbida was not found in association with any other beetle besides Pityophthorus juglandis. However, four additional Geosmithia species were found in P. juglandis galleries. When integrated with recent data from other continents, a global pattern of Geosmithia distribution across continents, latitudes, and vectors is emerging: of the 29 Geosmithia species found in the western USA, 12 have not been reported outside of the USA. The most frequently encountered species with the widest global distribution also had the broadest range of beetle vectors. Several Geosmithia spp. with very narrow vector ranges in Europe exhibited the similar degree of specialization in the USA. Such strong canalization in association could reflect an ancient origin of each individual association, or a
B. Forster; F. Meier; R. Gall
In 1990 and 1999, heavy storms accompanied by the worst gales ever recorded in Switzerland, struck Europe and left millions of cubic metres of windthrown Norway spruce trees; this provided breeding material for the eight-toothed spruce bark beetle (Ips typographus L.) and led to mass attacks in subsequent years which resulted in the additional loss...
Kolarík, Miroslav; Kostovcík, Martin; Pazoutová, Sylvie
Geosmithia spp. (Ascomycota: Hypocreales) are dry-spored fungi that occur in galleries built by many phloeophagous bark beetles. This study mapped the diversity, host spectrum and area of distribution of Geosmithia spp. occurring in galleries of bark beetle species with a Mediterranean distribution. Eighty-six wood samples of 19 tree species infested by 18 subcortical insect species were collected from across the Mediterranean Basin during the years 2003-2006. Geosmithia spp. were found in 82 samples of angiosperms and two host trees from the family Juniperaceae infested by 14 bark beetles and the bostrichid Scobicia pustulata, suggesting that the association of Geosmithia and phloeophagous bark beetles is very widespread in the Mediterranean. Geosmithia isolates were sorted into 13 operational taxonomic units (OTUs) based on their phenotype similarity and phylogeny of their ITS regions of rDNA (ITS1-5.8S-ITS2). The OTUs represent five known species (G. flava, G. langdonii, G. lavendula, G. pallida, G. putterillii) and seven undescribed taxa. Most of the bark beetles were associated with on average 1-2.5 OTUs per sample. G. lavendula, considered very uncommon in nature, was found as a common associate of bark beetles. Six out of 13 OTUs were found to be distributed in the Mediterranean but not in neighbouring areas of temperate Europe suggesting that Geosmithia spp. have a geographically limited distribution, probably due to their dependency on the geographically limited area of their vectors. The proportion of generalists and specialists among Geosmithia spp. was smaller compared with data from temperate Europe. A possible explanation is the effective dispersal of Geosmithia by polyphagous bostrichids across the niches defined by mutually exclusive bark beetles.
Nancy. E. Gillette; A. Steve Munson
The discovery and elucidation of volatile behavioral chemicals used by bark beetles to locate hosts and mates has revealed a rich potential for humans to sabotage beetle host-finding and reproduction. Here, we present a description of currently available semiochemical methods for use in monitoring and controlling bark beetle pests in western conifer forests. Delivery...
Flamm, R.O.; Pulley, P.E.; Coulson, R.N. (Texas A M Univ., College Station (United States))
The southern pine bark beetle guild [Dendroctonus frontalis Zimmermann, D. terebrans (Olivier), Ips calligraphus (Germar), I. grandicollis (Eichhoff), and I. avulsus (Eichhoff)] uses disturbed hosts as habitat for establishment of within-tree populations. The process of colonization of disturbed hosts was examined. Using a procedure designed to emulate effects of a lightning strike, pines were severely disturbed. Response was characterized by measuring beetle populations that (1) arrived at the trees and (2) successfully attacked the trees. Establishment of within-tree populations was characterized by measuring length of egg gallery excavated by attacking adults. The time delay between arrival and attack for D. frontalis and I. calligraphus was also calculated. Attack densities of both species became asymptotic as arrival increased. The percentage of arriving beetles that attacked ranged from 9 to 41 for D. frontalis and from 8 to 59 for I. calligraphus. Numbers of beetles that arrived at the tree but did not attack ranged from 2.7 to 50.2 beetles per dm[sup 2] for D. frontalis and from 0.2 to 10.0 beetles per dm[sup 2] for I. calligraphus. Most D. frontalis and I. calligraphus attacked on the day they arrived. The delay between arrival and attack was longer for I. calligraphus than the D. frontalis. Egg gallery excavated by D. frontalis increased throughout the study. Eventually, the Ips species were excluded from the lower half of the hole. The low attack densities observed in this study illustrate the significance of disturbed trees in providing refuges for enzootic levels of bark beetles. The aggregation behavior of beetle populations colonizing disturbed hosts supported the contention that these trees serve as foci for initiation of infestations. Furthermore, in disturbed pines, small numbers of beetles were capable of overcoming host defense systems.
Jane L. Hayes; Kenneth F. Raffa
This proceedings contains contributions from each author or group of authors who presented their current research at the bark beetle genetics workshop held 17-18 July 1998 on the campus of the University of Wisconsin in Madison, Wisconsin, USA. This was the second meeting on this subject; the first was held in 1992. The subject of bark beetle genetics is of growing,...
Faccoli, Massimo; Campo, Giuseppe; Perrotta, Giancarlo; Rassati, Davide
In summer 2014, the bark beetle Hypocryphalus scabricollis (Eichhoff) and the ambrosia beetle Xyleborus bispinatus Eichhoff, species new to Italy and Europe, respectively, were found for the first time in south-eastern Sicily (Italy). Large infestations of the two species were recorded in many plantations of common fig (Ficus carica L.) both in 2014 and 2015. Data concerning insect characteristics, taxonomy, and distribution are briefly reported.
Bisrat, S. A.; White, M. A.
Many of the direct influences of disturbances such as fire or insects on ecosystem function are well known. In contrast, the interactions among disturbances are less well understood. In the forests of the western United States, the interaction between bark beetle outbreaks and subsequent fires is a pressing management concern for a diverse political, economic, and ecological community but the disturbance interaction is generally unknown. For example, although conventional wisdom holds that bark beetle outbreaks will increase fire risk, limited field studies suggest the opposite may be true. To our knowledge, no study has attempted to study bark beetle - fire interactions over the entire western United States. Here, using five years (2000-2004) of manually collected aerial detection survey (ADS) polygons depicting the extent of bark beetle outbreaks and five years (2001-2005) of Moderate Resolution Imaging Spectroradiometer (MODIS) 1km fire images (MOD14), we calculated the influence of bark beetle outbreaks on one-year-lagged subsequent fire occurrence across the entire western United States. We converted the ADS polygons to raster format and co-registered all imagery to the Albers Equal Area projection. We then calculated the conditional probability of fire given bark beetle presence P(fire|bark beetles presence) and the conditional probability of fire given bark beetle absence P(fire|bark beetle absence). The presence of bark beetles increased the probability of one-year-lagged subsequent fire occurrence by 17% to 115% with an average value of 65%, strongly suggesting that bark beetle outbreaks in one year will increase the risk of fire in the next year. Key words: bark beetles, fire, disturbance interaction, conditional probability
Meddens, A. J.; Hicke, J. A.; Ferguson, C. A.
Outbreaks of aggressive bark beetle species cause widespread tree mortality, affecting wildlife habitat, wildfire risk, forest recovery, biogeochemical cycling, and biophysical processes. As a result, agencies responsible for forest management in the US and British Columbia are concerned about monitoring outbreaks and so conduct aerial surveys to map these forest disturbances. Here, we describe a gridded product of bark beetle disturbances for the western conterminous United States (1997-2009) and British Columbia (2001-2009). We converted aerial survey polygon data into 1-km2 grids for each combination of host type (e.g., lodgepole pine) and bark beetle species (e.g., mountain pine beetle) available in the US, and for each bark beetle species available in British Columbia. Polygon data are considered "affected area" because the polygons include live and killed trees. We converted affected area to mortality area within each grid cell for each year. We compared the number of killed trees from the US data set with high-resolution classified imagery in Idaho, Colorado, and New Mexico, finding that the number of trees reported by the aerial surveys in these locations was substantially underestimated. We adjusted mortality area for the US and found better matches with the spatial patterns and severity of the British Columbia mortality area. As a result, we produced US grids for lower (from the original aerial survey) and upper (with adjustment) estimates. Bark beetle mortality occurred across the entire study domain and temporal and spatial patterns differed among bark beetle species. The calculated mortality area from all bark beetles combined was 0.42 million ha for the lower estimate and 5.04 million ha for the upper estimate in the western conterminous US from 1997 to 2009, and 5.07 million ha in British Columbia from 2001 to 2009. The analyses suggest that mortality area caused by bark beetles in the western conterminous US exceeded the British Columbia mortality
Mukhamadiev, N.; Lynch, A.; O'Connor, C.; Sagitov, A.; Panyushkina, I. P.
On May 17, 2011, the spruce forest of Yile-Alatausky and Medeo National Parks in southeast Kazakhstan was surged by a high-energy cyclonic storm. Severe blowdown damaged several thousand hectare of Tian Shan spruce forest (Picea schrenkiana), with over 90% of trees killed in extensive areas. Bark beetle populations are increasing rapidly, particularly Ips hauseri, I. typographis, I. sexdentatus, and Pityogenes perfossus (all Coleoptera: Curculionidae). Little is known about the frequency or extent of either large storm events or bark beetle outbreaks in the Tian Shan Mountains, nor about associations between outbreaks of these species and temperature and precipitation regimes. Local managers are concerned that triggering bark beetle outbreaks during current unusually warm, dry conditions will have devastating consequences for the residual forest and forest outside of the blowdown. We characterize the bark beetle population response to the 2011 event to date, and reconstruct the temporal and spatial dynamics of historical disturbance events in the area using dendrochronology. Additionally temperature and precipitation-sensitive tree-ring width chronologies from the Tian Shan Mountains are analyzed to determine high- and low-frequency variability of climate for the past 200 years. Catastrophic windstorm disturbances may play a crucial role in determining forest structure across the mountains. We hypothesize that the Tian Shan spruce forest could be prone to severe storm winds and subsequent bark beetle outbreaks and never reach an old-growth phase between events.
Hicke, J. A.; Jenkins, J. C.
In the western United States, bark beetle outbreaks affect millions of hectares of forests. These disturbances have multiple effects on ecosystems, including modifications to biogeochemical cycles, interactions with fire, and changes in land cover type and species composition. In recent years, extensive outbreaks have occurred in multiple forest ecosystems in the West, thought to be caused by climate variability and stand structure. In this study, we focus on epidemics of mountain pine beetle. We used USDA Forest Service inventories and a model to estimate lodgepole pine susceptibility to mountain pine beetle attack in the West. The model considers stand age, stem density, and percentage of large lodgepole pine to estimate stand susceptibility. Over 150,000 trees in 4454 plots across the western United States were used to compute susceptibility at the plot scale as well as map susceptibility at the county scale. We found that regional susceptibility was high (estimated potential of losses of 34% of stand basal area) for 2.8 Mha, or 46%, of lodgepole pine forests. The highest susceptibility occurred in the Rocky Mountains, with lower susceptibility in coastal states. This study reveals that a substantial fraction of lodgepole pine forest could be subjected to bark beetle outbreaks under current climate conditions. Because climate and weather affect beetle populations, projected future warming will influence outbreak regimes. Thus, forest ecosystems in the West may experience more frequent, extensive, and/or severe disturbances than in recent decades due to current stand structure, and these disturbances may be intensified under climate change.
Diana L. Six
Full Text Available Ectosymbioses among bark beetles (Curculionidae, Scolytinae and fungi (primarily ophiostomatoid Ascomycetes are widespread and diverse. Associations range from mutualistic to commensal, and from facultative to obligate. Some fungi are highly specific and associated only with a single beetle species, while others can be associated with many. In addition, most of these symbioses are multipartite, with the host beetle associated with two or more consistent partners. Mycangia, structures of the beetle integument that function in fungal transport, have evolved numerous times in the Scolytinae. The evolution of such complex, specialized structures indicates a high degree of mutual dependence among the beetles and their fungal partners. Unfortunately, the processes that shaped current day beetle-fungus symbioses remain poorly understood. Phylogeny, the degree and type of dependence on partners, mode of transmission of symbionts (vertical vs. horizontal, effects of the abiotic environment, and interactions among symbionts themselves or with other members of the biotic community, all play important roles in determining the composition, fidelity, and longevity of associations between beetles and their fungal associates. In this review, I provide an overview of these associations and discuss how evolution and ecological processes acted in concert to shape these fascinating, complex symbioses.
Six, Diana L.
Ectosymbioses among bark beetles (Curculionidae, Scolytinae) and fungi (primarily ophiostomatoid Ascomycetes) are widespread and diverse. Associations range from mutualistic to commensal, and from facultative to obligate. Some fungi are highly specific and associated only with a single beetle species, while others can be associated with many. In addition, most of these symbioses are multipartite, with the host beetle associated with two or more consistent partners. Mycangia, structures of the beetle integument that function in fungal transport, have evolved numerous times in the Scolytinae. The evolution of such complex, specialized structures indicates a high degree of mutual dependence among the beetles and their fungal partners. Unfortunately, the processes that shaped current day beetle-fungus symbioses remain poorly understood. Phylogeny, the degree and type of dependence on partners, mode of transmission of symbionts (vertical vs. horizontal), effects of the abiotic environment, and interactions among symbionts themselves or with other members of the biotic community, all play important roles in determining the composition, fidelity, and longevity of associations between beetles and their fungal associates. In this review, I provide an overview of these associations and discuss how evolution and ecological processes acted in concert to shape these fascinating, complex symbioses. PMID:26467964
Hood, Sharon; Sala, Anna; Heyerdahl, Emily K; Boutin, Marion
Induced defense is a common plant strategy in response to herbivory. Although abiotic damage, such as physical wounding, pruning, and heating, can induce plant defense, the effect of such damage by large-scale abiotic disturbances on induced defenses has not been explored and could have important consequences for plant survival facing future biotic disturbances. Historically, low-severity wildfire was a widespread, frequent abiotic disturbance in many temperate coniferous forests. Native Dendroctonus and Ips bark beetles are also a common biotic disturbance agent in these forest types and can influence tree mortality patterns after wildfire. Therefore, species living in these disturbance-prone environments with strategies to survive both frequent fire and bark beetle attack should be favored. One such example is Pinus ponderosa forests of western North America. These forests are susceptible to bark beetle attack and frequent, low-severity fire was common prior to European settlement. However, since the late 1800s, frequent, low-severity fires have greatly decreased in these forests. We hypothesized that non-lethal, low-severity, wildfire induces resin duct defense in P. ponderosa and that lack of low-severity fire relaxes resin duct defense in forests dependent on frequent, low-severity fire. We first compared axial resin duct traits between trees that either survived or died from bark beetle attacks. Next, we studied axial ducts using tree cores with crossdated chronologies in several natural P. ponderosa stands before and after an individual wildfire and, also, before and after an abrupt change in fire frequency in the 20th century. We show that trees killed by bark beetles invested less in resin ducts relative to trees that survived attack, suggesting that resin duct-related traits provide resistance against bark beetles. We then show low-severity fire induces resin duct production, and finally, that resin duct production declines when fire ceases. Our results
Hayes, Christopher J; DeGomez, Tom E; Clancy, Karen M; Williams, Kelly K; McMillin, Joel D; Anhold, John A
Lindgren funnel traps baited with aggregation pheromones are widely used to monitor and manage populations of economically important bark beetles (Coleoptera: Scolytidae). This study was designed to advance our understanding of how funnel trap catches assess bark beetle communities and relative abundance of individual species. In the second year (2005) of a 3-yr study of the bark beetle community structure in north-central Arizona pine (Pinus spp.) forests, we collected data on stand structure, site conditions, and local bark beetle-induced tree mortality at each trap site. We also collected samples of bark from infested (brood) trees near trap sites to identify and determine the population density of bark beetles that were attacking ponderosa pine, Pinus ponderosa Douglas ex Lawson, in the area surrounding the traps. Multiple regression models indicated that the number of Dendroctonus and Ips beetles captured in 2005 was inversely related to elevation of the trap site, and positively associated with the amount of ponderosa pine in the stand surrounding the site. Traps located closer to brood trees also captured more beetles. The relationship between trap catches and host tree mortality was weak and inconsistent in forest stands surrounding the funnel traps, suggesting that trap catches do not provide a good estimate of local beetle-induced tree mortality. However, pheromone-baited funnel trap data and data from gallery identification in bark samples produced statistically similar relative abundance profiles for the five species of bark beetles that we examined, indicating that funnel trap data provided a good assessment of species presence and relative abundance.
Full Text Available Invasive bark beetles are posing a major threat to forest resources around the world. DAISIE’s web-based and printed databases of invasive species in Europe provide an incomplete and misleading picture of the alien scolytines and platypodines. We present a review of the alien bark beetle fauna of Europe based on primary literature through 2009. We find that there are 18 Scolytinae and one Platypodinae species apparently established in Europe, from 14 different genera. Seventeen species are naturalized. We argue that Trypodendron laeve, commonly considered alien in Europe, is a native species; conversely, we hypothesize that Xyleborus pfeilii, which has always been treated as indigenous, is an alien species from Asia. We also point out the possibility that the Asian larch bark beetle Ips subelongatus is established in European Russia. We show that there has been a marked acceleration in the rate of new introductions to Europe, as is also happening in North America: seven alien species were first recorded in the last decade. We present information on the biology, origins, and distributions of the alien species. All but four are polyphagous, and 11 are inbreeders: two traits which increase invasiveness. Eleven species are native to Asia, six to the Americas, and one is from the Canary Islands. The Mediterranean is especially favorable for invasives, hosting a large proportion of the aliens (8/18. Italy, Spain and France have the largest numbers of alien species (15, 10 and 7 respectively. We point out that the low numbers for at least some countries is likely due to under-reporting. Finally, we discuss the difficulties associated with identifying newly invasive species. Lack of good illustrations and keys hinder identification, particularly for species coming from Asia and Oceania.
Morrissey, Christy A; Albert, Courtney A; Dods, Patti L; Cullen, William R; Lai, Vivian W M; Elliott, John E
The arsenic-based pesticide, monosodium methanearsonate (MSMA), is presently being evaluated for re-registration in Canada and the United States and has been widely used in British Columbia to help suppress Mountain Pine Beetle (MPB) outbreaks. We assessed the availability and exposure of MSMA to woodpeckers and other forest birds that may prey directly on contaminated bark beetles. Total arsenic residues in MPB from MSMA treated trees ranged from 1.3-700.2 microg g(-1) dw (geometric mean 42.0 microg g(-1)) with the metabolite monomethyl arsonic acid (MMAA) contributing 90-97% to the total arsenic extracted. Live adult and larval beetles were collected from treated trees and reached concentrations up to 327 microg g(-1) dw. MPBs from reference trees had significantly lower arsenic concentrations averaging 0.19 microg g(-1) dw. Woodpeckers foraged more heavily on MSMAtreesthat contained beetles with lower arsenic residues, suggesting those trees had reduced MSMAtranslocation and possibly greater live beetle broods. Blood samples from five species of woodpeckers and other forest passerines breeding within 1 km of MSMA stands contained elevated levels of total arsenic but with large individual variability (geometric mean = 0.18 microg g(-1) dw, range 0.02-2.20 microg g(-1). The results indicate that there is significant accumulation and transfer of organic arsenic within the food chain at levels that may present a toxicity risk to avian wildlife.
Jose F. Negron; Barbara J. Bentz; Christopher J. Fettig; Nancy Gillette; E. Matthew Hansen; Jane L. Hayes; Rick G. Kelsey; John E. Lundquist; Ann M. Lynch; Robert A. Progar; Steven J. Seybold
Bark beetles cause extensive tree mortality in coniferous forests of western North America and play an important role in the disturbance ecology of these ecosystems. Recently, elevated populations of bark beetles have been observed in all conifer forest types across the western United States. This has heightened public awareness of the issue and triggered legislation...
Ryan S. Davis; Sharon Hood; Barbara J. Bentz
Bark beetles can cause substantial mortality of trees that would otherwise survive fire injuries. Resin response of fire-injured northern Rocky Mountain ponderosa pine (Pinus ponderosa Douglas ex P. Lawson & C. Lawson) and specific injuries that contribute to increased bark beetle attack susceptibility and brood production are unknown. We monitored ponderosa pine...
Full Text Available In the dry Swiss Rhone Valley, Scots pine forests have experienced increased mortality in recent years. It has commonly been assumed that drought events and bark beetles fostered the decline, however, whether bark beetle outbreaks increased in recent years and whether they can be linked to drought stress or increasing temperature has never been studied.
Jesse L. Morris; Stuart Cottrell; Chris Fettig; Winslow D. Hansen; Rosemary L. Sherriff; Vachel A. Carter; Jennifer L. Clear; Jessica Clement; R. Justin DeRose; Jeffrey A. Hicke; Philip E. Higuera; Katherine M. Mattor; Alistair W. R. Seddon; Heikki T. Sepp; John D. Stednick; Steven J. Seybold
1. Recent bark beetle outbreaks in North America and Europe have impacted forested landscapes and the provisioning of critical ecosystem services. The scale and intensity of many recent outbreaks are widely believed to be unprecedented. 2. The effects of bark beetle outbreaks on ecosystems are often measured in terms of area affected, host tree mortality rates, and...
Christopher J. Allender; Karen M. Clancy; Tom E. DeGomez; Joel D. McMillin; Scott A. Woolbright; Paul Keim; David M. Wagner
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...
D.M. Grosman; C.J. Fettig; C.L. Jorgensen; A.S. Munson
Bark beetles (Coleoptera: Curculionidae, Scolytinae) are important tree mortality agents in western coniferous forests. Protection of individual trees from bark beetle attack has historically involved applications of liquid formulations of contact insecticides to the tree bole using hydraulic sprayers. More recently, researchers looking for more portable and...
Rick G. Kelsey; D. Gallego; F.J. Sánchez-Garcia; J.A. Pajares
Tree mortality from temperature-driven drought is occurring in forests around the world, often in conjunction with bark beetle outbreaks when carbon allocation to tree defense declines. Physiological metrics for detecting stressed trees with enhanced vulnerability prior to bark beetle attacks remain elusive. Ethanol, water, monoterpene concentrations, and composition...
Stark, R.W.; Miller, P.R.; Cobb, F.W. Jr.; Wood, D.L.; Parmeter, J.R. Jr.
A total of 107 beetle-killed and 963 nearest-neighbor ponderosa pines were examined to determine the association between severity of atmospheric pollution injury and infestation by bark beetles. Trees exhibiting advanced symptoms of pollution injury were most frequently infested by the western pine beetle, Dendroctonus brevicomis, and the mountain pine beetle, D. ponderosae. The degree of injury and incidence of bark beetle infestation were not related to total height, diameter, length of live and dead crown or crown class. As severity of oxidant injury increased, live crown ratio decreased and incidence of bark beetle infestation increased. One hundred noninfested trees in each of three disease categories, advanced, intermediate, and healthy, were examined for evidence of prior beetle attacks. Thirty-six percent of the advanced-diseased trees versus only 5% of the healthy trees were attacked. Thus, the beetles may discriminate between healthy and diseased trees at a distance, upon contact with the host, or both. These studies indicate strongly that atmospheric pollution injury predisposes ponderosa pine to bark beetle infestations. 3 references, 7 tables.
Kelly K. Williams; Joel D. McMillin; Tom E. DeGomez; Karen M. Clancy; Andy Miller
We examined abundance and flight periodicity of five Ips and six Dendroctonus species (Coleoptera: Curculionidae, Scolytinae) among three different elevation bands in ponderosa pine (Pinus ponderosa Douglas ex. Lawson) forests of northcentral Arizona. Bark beetle populations were monitored at 10 sites in each of three elevation...
Y. Salinas-Moreno; A. Ager; C.F. Vargas; J.L. Hayes; G. Zuniga
Bark beetles of the genus Dendroctonus are natural inhabitants of forests; under particular conditions some species of this genus can cause large-scale tree mortality. However, only in recent decades has priority been given to the comprehensive study of these insects in Mexico. Mexico possesses high ecological diversity in Dendroctonus-...
Pistone, Dario; Mugu, Sigrid; Jordal, Bjarte Henry
Deep level insect relationships are generally difficult to resolve, especially within taxa of the most diverse and species rich holometabolous orders. In beetles, the major diversity occurs in the Phytophaga, including charismatic groups such as leaf beetles, longhorn beetles and weevils. Bark and ambrosia beetles are wood boring weevils that contribute 12 percent of the diversity encountered in Curculionidae, one of the largest families of beetles with more than 50000 described species. Phylogenetic resolution in groups of Cretaceous age has proven particularly difficult and requires large quantity of data. In this study, we investigated 100 nuclear genes in order to select a number of markers with low evolutionary rates and high phylogenetic signal. A PCR screening using degenerate primers was applied to 26 different weevil species. We obtained sequences from 57 of the 100 targeted genes. Sequences from each nuclear marker were aligned and examined for detecting multiple copies, pseudogenes and introns. Phylogenetic informativeness (PI) and the capacity for reconstruction of previously established phylogenetic relationships were used as proxies for selecting a subset of the 57 amplified genes. Finally, we selected 16 markers suitable for large-scale phylogenetics of Scolytinae and related weevil taxa.
Full Text Available Deep level insect relationships are generally difficult to resolve, especially within taxa of the most diverse and species rich holometabolous orders. In beetles, the major diversity occurs in the Phytophaga, including charismatic groups such as leaf beetles, longhorn beetles and weevils. Bark and ambrosia beetles are wood boring weevils that contribute 12 percent of the diversity encountered in Curculionidae, one of the largest families of beetles with more than 50000 described species. Phylogenetic resolution in groups of Cretaceous age has proven particularly difficult and requires large quantity of data. In this study, we investigated 100 nuclear genes in order to select a number of markers with low evolutionary rates and high phylogenetic signal. A PCR screening using degenerate primers was applied to 26 different weevil species. We obtained sequences from 57 of the 100 targeted genes. Sequences from each nuclear marker were aligned and examined for detecting multiple copies, pseudogenes and introns. Phylogenetic informativeness (PI and the capacity for reconstruction of previously established phylogenetic relationships were used as proxies for selecting a subset of the 57 amplified genes. Finally, we selected 16 markers suitable for large-scale phylogenetics of Scolytinae and related weevil taxa.
Hicke, J. A.; Meddens, A. J.; Allen, C. D.
Bark beetle outbreaks and wildfires are significant forest disturbances that respond strongly to climate and affect future climate through carbon cycling. Extensive tree mortality has occurred in western North America as a result of these disturbances. Here we present an analysis that quantifies impacts of these two disturbances to tree carbon stocks. Mortality area from bark beetles was derived from aerial surveys in 1997-2010 in the western US and 2001-2010 in British Columbia that were converted to mortality area by multiplying by species-specific crown areas and, in the case of the US, adjusted for underestimation. We summed moderate- and high-severity burned areas in forests from the Monitoring Trends in Burn Severity (MTBS) database from 1984-2009 to estimate mortality area from forest fires. Mortality area was then combined with spatially explicit maps of carbon stocks to estimate the amount of carbon in killed trees. Notable findings include that the mortality area from bark beetle outbreaks in the western US was comparable to the mortality area in British Columbia during the last few decades. In the western US, mortality area from bark beetles was similar to or exceeded that from forest fires. Carbon stocks in trees killed by these two disturbance types (beetles and fire) had similar spatial and temporal patterns as tree mortality, illustrating the importance of each of these disturbances in governing regional forest carbon fluxes.
Andrew D. Taylor; Jane L. Hayes; John C. Moser
Much of the life cycles of bark beetles and their associates are spent under the bark of the host tree and are impossible to observe under completely natural conditions. To observe the behavior and development of insects in the phloem layer, phloem sandwiches have been developed, in which a piece of bark and phloem is removed from a live tree and pressed against a...
Allender, Christopher J; Clancy, Karen M; Degomez, Tom E; McMillin, Joel D; Woolbright, Scott A; Keim, Paul; Wagner, David M
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 I. 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 a broad region. We conclude that our results are consistent with strong dispersal patterns and large population sizes of all three species.
Rassati, Davide; Haack, Robert A; Knížek, Miloš; Faccoli, Massimo
Several native species of bark- and wood-boring beetles (Coleoptera) have expanded their range within their native biogeographic regions in the last years, but the role of human activity in driving this phenomenon has been underinvestigated. Here we analyze 3 yr of trapping records of native bark- and wood-boring beetles (Cerambycidae and Scolytinae) collected at 12 Italian ports and their surrounding forests to help elucidate the human role in the movement of native species within their native biogeographic region. We trapped several species that occurred either inside or outside their native distributional range within Italy. Species richness and abundance of those species found in the ports located within their native range were most strongly associated with the amount of forest cover in the surrounding landscape, suggesting that they could have arrived in the ports from the nearby forests. The abundance of the species found outside their native range was instead most strongly linked to the amount of national imports arriving at the port where trapping occurred, suggesting that they were likely introduced to the ports from other parts of Italy. This study demonstrates that national sea transportation can favor species range expansion within a country, and confirms that the forests that surround ports can serve as a source of species that can be potentially moved with exports. © The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: firstname.lastname@example.org.
Zhao, Tao; Krokene, Paal; Hu, Jiang; Christiansen, Erik; Björklund, Niklas; Långström, Bo; Solheim, Halvor; Borg-Karlson, Anna-Karin
Background Tree-killing bark beetles (Coleoptera, Scolytinae) are among the most economically and ecologically important forest pests in the northern hemisphere. Induction of terpenoid-based oleoresin has long been considered important in conifer defense against bark beetles, but it has been difficult to demonstrate a direct correlation between terpene levels and resistance to bark beetle colonization. Methods To test for inhibitory effects of induced terpenes on colonization by the spruce bark beetle Ips typographus (L.) we inoculated 20 mature Norway spruce Picea abies (L.) Karsten trees with a virulent fungus associated with the beetle, Ceratocystis polonica (Siem.) C. Moreau, and investigated induced terpene levels and beetle colonization in the bark. Results Fungal inoculation induced very strong and highly variable terpene accumulation 35 days after inoculation. Trees with high induced terpene levels (n = 7) had only 4.9% as many beetle attacks (5.1 vs. 103.5 attacks m−2) and 2.6% as much gallery length (0.029 m m−2 vs. 1.11 m m−2) as trees with low terpene levels (n = 6). There was a highly significant rank correlation between terpene levels at day 35 and beetle colonization in individual trees. The relationship between induced terpene levels and beetle colonization was not linear but thresholded: above a low threshold concentration of ∼100 mg terpene g−1 dry phloem trees suffered only moderate beetle colonization, and above a high threshold of ∼200 mg terpene g−1 dry phloem trees were virtually unattacked. Conclusion/Significance This is the first study demonstrating a dose-dependent relationship between induced terpenes and tree resistance to bark beetle colonization under field conditions, indicating that terpene induction may be instrumental in tree resistance. This knowledge could be useful for developing management strategies that decrease the impact of tree-killing bark beetles. PMID:22028932
Full Text Available Tree-killing bark beetles (Coleoptera, Scolytinae are among the most economically and ecologically important forest pests in the northern hemisphere. Induction of terpenoid-based oleoresin has long been considered important in conifer defense against bark beetles, but it has been difficult to demonstrate a direct correlation between terpene levels and resistance to bark beetle colonization.To test for inhibitory effects of induced terpenes on colonization by the spruce bark beetle Ips typographus (L. we inoculated 20 mature Norway spruce Picea abies (L. Karsten trees with a virulent fungus associated with the beetle, Ceratocystis polonica (Siem. C. Moreau, and investigated induced terpene levels and beetle colonization in the bark.Fungal inoculation induced very strong and highly variable terpene accumulation 35 days after inoculation. Trees with high induced terpene levels (n = 7 had only 4.9% as many beetle attacks (5.1 vs. 103.5 attacks m(-2 and 2.6% as much gallery length (0.029 m m(-2 vs. 1.11 m m(-2 as trees with low terpene levels (n = 6. There was a highly significant rank correlation between terpene levels at day 35 and beetle colonization in individual trees. The relationship between induced terpene levels and beetle colonization was not linear but thresholded: above a low threshold concentration of ∼100 mg terpene g(-1 dry phloem trees suffered only moderate beetle colonization, and above a high threshold of ∼200 mg terpene g(-1 dry phloem trees were virtually unattacked.This is the first study demonstrating a dose-dependent relationship between induced terpenes and tree resistance to bark beetle colonization under field conditions, indicating that terpene induction may be instrumental in tree resistance. This knowledge could be useful for developing management strategies that decrease the impact of tree-killing bark beetles.
Hernández-García, Juan Alfredo; Briones-Roblero, Carlos Iván; Rivera-Orduña, Flor N; Zúñiga, Gerardo
Dendroctonus bark beetles comprise 20 taxonomically recognized species, which are one of the most destructive pine forest pests in North and Central America, and Eurasia. The aims of this study were to characterize the gut bacterial diversity, to determine the core bacteriome and to explore the ecological association between these bacteria and bark beetles. A total of five bacterial phyla were identified in the gut of 13 Dendroctonus species; Proteobacteria was the most abundant, followed by Firmicutes, Fusobacteria, Actinobacteria and Deinococcus-Thermus. The α-diversity was low as demonstrated in previous studies and significant differences in β-diversity were observed. The core bacteriome was composed of Enterobacter, Pantoea, Pseudomonas, Rahnella, Raoultella, and Serratia. The tanglegram between bacteria and bark beetles suggests that members of bacterial community are acquired from the environment, possibly from the host tree. These findings improve the knowledge about the bacterial community composition, and provide the bases to study the metabolic functions of these bacteria, as well as their interaction with these bark beetles.
Ghimire, B.; Williams, C. A.; Collatz, G. J.; Masek, J. G.
Recently bark beetle outbreaks have been increasing in western United States forests due to increases in temperatures and prolonged occurrence of droughts. Bark beetle outbreaks transfer carbon from the live photosynthesizing pools to the dead respiring pool where carbon slowly decomposes into the atmosphere causing landscapes to change from a net sink to source of carbon. Previous studies have usually been conducted at small localized areas, focused only on one or two bark beetle types or encompass a single outbreak event. The literature largely ignores the influence of bark beetle mortality on carbon balance at both local and regional scales by focusing on multiple bark beetles types and events. This study uses a combination of the Carnegie Ames Stanford Approach (CASA) carbon cycle model driven by remotely sensed biophysical observations, Forest Inventory and Analysis (FIA) derived post-disturbance biomass regeneration trajectories, and mortality rates obtained from Aerial Detection Survey (ADS) insect outbreak polygons. The synthesis of the carbon cycle based modeling approach and different data products results in characteristic carbon trajectories for Net Ecosystem Productivity (NEP), Net Primary Productivity (NPP) and heterotrophic respiration associated with insect outbreaks. This study demonstrates that bark beetle events change landscapes from a sink to source of carbon at a local scale but at a larger regional level the influence of bark beetle outbreaks are not prominent compared to other disturbance agents.
Daniel R. West
Full Text Available Conifer defenses against bark beetle attack include, but are not limited to, quantitative and qualitative defenses produced prior to attack. Our objective was to assess host defenses of lodgepole pine and ponderosa pine from ecotone stands. These stands provide a transition of host species for mountain pine beetle (Dendroctonus ponderosae; MPB. We asked two questions: (1 do the preformed quantitative host defenses (amount of resin and (2 the preformed qualitative host defenses (monoterpene constituents differ between lodgepole and ponderosa pines. We collected oleoresins at three locations in the Southern Rocky Mountains from 56 pairs of the pine species of similar size and growing conditions. The amount of preformed-ponderosa pine oleoresins exuded in 24 h (mg was almost four times that of lodgepole pine. Total qualitative preformed monoterpenes did not differ between the two hosts, though we found differences in all but three monoterpenes. No differences were detected in α-pinene, γ-terpinene, and bornyl acetate. We found greater concentrations of limonene, β-phellandrene, and cymene in lodgepole pines, whereas β-pinene, 3-carene, myrcene, and terpinolene were greater in ponderosa pine. Although we found differences both in quantitative and qualitative preformed oleoresin defenses, the ecological relevance of these differences to bark beetle susceptibility have not been fully tested.
Jonathan A Cale
Full Text Available Mountain pine beetle (Dendroctonus ponderosae has killed millions of hectares of pine forests in western North America. Beetle success is dependent upon a community of symbiotic fungi comprised of Grosmannia clavigera, Ophiostoma montium, and Leptographium longiclavatum. Factors regulating the dynamics of this community during pine infection are largely unknown. However, fungal volatile organic compounds (FVOCs help shape fungal interactions in model and agricultural systems and thus may be important drivers of interactions among bark beetle-associated fungi. We investigated whether FVOCs can mediate interspecific interactions among mountain pine beetle's fungal symbionts by affecting fungal growth and reproduction. Headspace volatiles were collected and identified to determine species-specific volatile profiles. Interspecific effects of volatiles on fungal growth and conidia production were assessed by pairing physically-separated fungal cultures grown either on a carbon-poor or -rich substrate, inside a shared-headspace environment. Fungal VOC profiles differed by species and influenced the growth and/or conidia production of the other species. Further, our results showed that FVOCs can be used as carbon sources for fungi developing on carbon-poor substrates. This is the first report demonstrating that FVOCs can drive interactions among bark beetle fungal symbionts, and thus are important factors in beetle attack success.
Boone, Celia K; Six, Diana L; Zheng, Yanbing; Raffa, Kenneth F
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 I. 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 I. 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 I. 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.
Aflitto, Nicholas C; Hofstetter, Richard W
Acoustic technology is a potential tool to protect wood materials and eventually live trees from colonization by bark beetles. Bark beetles such as the southern pine beetle Dendroctonus frontalis, western pine beetle D. brevicomis and pine engraver Ips pini (Coleoptera: Curculionidae) use chemical and acoustic cues to communicate and to locate potential mates and host trees. In this study, the efficacy of sound treatments on D. frontalis, D. brevicomis and I. pini entry into tree materials was tested. Acoustic treatments significantly influenced whether beetles entered pine logs in the laboratory. Playback of artificial sounds reduced D. brevicomis entry into logs, and playback of stress call sounds reduced D. frontalis entry into logs. Sound treatments had no effect on I. pini entry into logs. The reduction in bark beetle entry into logs using particular acoustic treatments indicates that sound could be used as a viable management tool. © 2013 Society of Chemical Industry.
Fabryová, Anna; Kostovčík, Martin; Díez-Méndez, Alexandra; Jiménez-Gómez, Alejandro; Celador-Lera, Lorena; Saati-Santamaría, Zaki; Sechovcová, Hana; Menéndez, Esther; Kolařik, Miroslav; García-Fraile, Paula
Bark beetles reproduce and overwinter under the bark of trees, and are associated with bacteria that may influence the fitness of their hosts. As regard the aim of this study was to test the metabolic potential of bacterial strains, isolated from the bark beetle species Cryphalus piceae, Ips typographus and Pityophthorus pityophthorus and collected in the Czech Republic from fir, spruce and pine trees, respectively, to degrade plant cell compounds. The bacterial strains were identified as belonging to the genera Curtobacterium, Erwinia, Pantoea, Pseudomonas, Rahnella, Staphylococcus, and Yersinia. Several activities related to the degradation of lignocellulosic materials, such as cellulose, xylan and starch, were found. Moreover, the genomes of three of these strains were sequenced and analyzed, and the presence of the enzymatic machinery required for biomass hydrolysis was discovered. This finding supports the idea that bacteria aid in the provision of nutrients to the beetle from the hydrolysis of tree compounds, results that are relevant for studying the ecological implication of bacterial strains in the bark beetle life cycle. In addition, the activities found in association with the bacterial strains could be useful in biotechnological processes, such as the production of biofuels from biomass, colorant degradation, in the textile industry and for wastewater treatments. Furthermore, the gene sequences of the lignocellulolytic enzymes found within the genomes serve as a basis for future studies regarding the potential application of these bacteria, and their metabolic machinery, in processes such as biomass hydrolysis and bioremediation. Copyright © 2017 Elsevier B.V. All rights reserved.
John A. Byers
Full Text Available A paradigm developed in the 1970s that Ips bark beetles biosynthesize their aggregation pheromone components ipsenol and ipsdienol by hydroxylating myrcene, a host tree monoterpene. Similarly, host α-pinene was hydroxylated to a third pheromone component cis-verbenol. In 1990, however, we reported that amounts of ipsenol and ipsdienol produced by male Ips paraconfusus (Coleoptera: Scolytinae feeding in five host pine species were nearly the same, even though no detectable myrcene precursor was detected in one of these pines (Pinus sabiniana. Subsequent research showed ipsenol and ipsdienol are also biosynthesized from smaller precursors such as acetate and mevalonate, and this de novo pathway is the major one, while host tree myrcene conversion by the beetle is the minor one. We report concentrations of myrcene, α-pinene and other major monoterpenes in five pine hosts (Pinus ponderosa, P. lambertiana, P. jeffreyi, P. sabiniana, and P. contorta of I. paraconfusus. A scheme for biosynthesis of ipsdienol and ipsenol from myrcene and possible metabolites such as ipsenone is presented. Mass spectra and quantities of ipsenone are reported and its possible role in biosynthesis of aggregation pheromone. Coevolution of bark beetles and host trees is discussed in relation to pheromone biosynthesis, host plant selection/suitability, and plant resistance.
Marini, Lorenzo; Økland, Bjørn; Jönsson, Anna Maria
Bark beetles are among the most devastating biotic agents affecting forests globally and several species are expected to be favored by climate change. Given the potential interactions of insect outbreaks with other biotic and abiotic disturbances, and the potentially strong impact of changing....... typographus that may provide a mechanism for population decline after population eruptions. Generality in the effects of complex climatic events across different geographical areas suggests that the large-scale drivers can be used as early warning indicators of increasing local outbreak probability....
Andrew T. Hudak; Ben Bright; Jose Negron; Robert McGaughey; Hans-Erik Andersen; Jeffrey A. Hicke
Recent bark beetle outbreaks in western North America have been widespread and severe. High tree mortality due to bark beetles affects the fundamental ecosystem processes of primary production and decomposition that largely determine carbon balance (Kurz et al. 2008, Pfeifer et al. 2011, Hicke et al. 2012). Forest managers need accurate data on beetle-induced tree...
National Aeronautics and Space Administration — This data set provides annual estimates of tree mortality due to fires and bark beetles from 2003 to 2012 on forestland in the continental western United States....
Martin N. Andersson
Full Text Available Coniferous bark beetles (Coleoptera: Curculionidae: Scolytinae locate their hosts by means of olfactory signals, such as pheromone, host, and nonhost compounds. Behavioral responses to these volatiles are well documented. However, apart from the olfactory receptor neurons (ORNs detecting pheromones, information on the peripheral olfactory physiology has for a long time been limited. Recently, however, comprehensive studies on the ORNs of the spruce bark beetle, Ips typographus, were conducted. Several new classes of ORNs were described and odor encoding mechanisms were investigated. In particular, links between behavioral responses and ORN responses were established, allowing for a more profound understanding of bark beetle olfaction. This paper reviews the physiology of bark beetle ORNs. Special focus is on I. typographus, for which the available physiological data can be put into a behavioral context. In addition, some recent field studies and possible applications, related to the physiological studies, are summarized and discussed.
Jose F. Negron; Jeffrey J. Witcosky; Robert J. Cain; James R. LaBonte; Donald A. Duerr; Sally J. McElwey; Jana C. Lee; Steven J. Seybold
An exotic bark beetle from Asia, the banded elm bark beetle, Scolytus schevyrewi, has been discovered in 21 states of the United States. Although its point of entry is not known, a survey of museum specimens suggests that it has been in the US for at least 10 years. It is most abundant in western states, attacks primarily American and Siberian elms, and carries spores...
Yin, Mingliang; Wingfield, Michael J; Zhou, Xudong; de Beer, Z Wilhelm
Ophiostoma spp. (Ophiostomatales, Ascomycota) are well-known fungi associated with bark beetles (Coleoptera: Scolytinae). Some of these are serious tree pathogens, while the majority is blue-stain agents of timber. In recent years, various bark beetle species have been attacking spruce forests in Qinghai province, China, causing significant damage. A preliminary survey was done to explore the diversity of the ophiostomatoid fungal associates of these beetles. The aims of the present study were to identify and characterize new Ophiostoma spp. associated with spruce-infesting bark beetles in Qinghai Province, and to resolve phylogenetic relationships of Ophiostoma spp. related to the Chinese isolates, using multigene phylogenetic analyses. Results obtained from four gene regions (ribosomal internal transcribed spacer regions, β-tubulin, calmodulin, translation elongation factor-1α) revealed five new Ophiostoma spp. from Qinghai. These included O. nitidus sp. nov., O. micans sp. nov., and O. qinghaiense sp. nov. in a newly defined O. piceae complex. The other two new species, O. poligraphi sp. nov. and O. shangrilae sp. nov., grouped in the O. brunneo-ciliatum complex. Based on DNA sequence and morphological comparisons, we also show that O. arduennense and O. torulosum are synonyms of O. distortum, while O. setosum is a synonym of O. cupulatum. Copyright © 2016 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.
Rhoades, C.; Elder, K.; Hubbard, R.; Porth, L.
Forested watersheds of western North America are currently undergoing rapid and extensive canopy mortality caused by a variety of insect species. The mountain pine bark beetle (Dendroctonus ponderosae) began to attack lodgepole pine (Pinus contorta) at the USFS Fraser Experimental Forest in central Colorado in 2002. By 2007, bark beetles had killed 78% of the overstory pine in Fraser research watersheds on average. The hydrologic, climatic, biogeochemical and vegetation records at the Fraser Experimental Forest provide a unique opportunity to quantify the impacts of this widespread, but poorly understood forest disturbance relative to a multi-decade pre-disturbance period. Here we compare seasonal streamwater chemistry and annual nutrient export for the five years since the bark beetle outbreak began with the pre- attack record. Patterns in post-outbreak streamwater biogeochemistry are compared to changes is species composition and proportional loss of overstory basal area for four basins. The influence of the outbreak will depend upon an aggregate of short (i.e. halted overstory water and nutrient use) and longer-term (i.e. altered canopy interception, windthrow, and understory growth) processes, so the hydrologic and biogeochemical implications of current beetle activity will not be fully realized for decades.
Jose F. Negron; Joel D. McMillin; John A. Anhold; Dave Coulson
Extensive ponderosa pine (Pinus ponderosa Dougl. ex Laws.) mortality associated with a widespread severe drought and increased bark beetle (Coleoptera: Curculionidae, Scolytinae) populations occurred in Arizona from 2001 to 2004. A complex of Ips beetles including: the Arizona fivespined ips, Ips lecontei Swaine...
Kirsten E. Haberkern; Barbara L. Illman; Kenneth F. Raffa
We examined the major bark beetles and associated fungi colonizing subcortical tissues of white spruce (Picea glauca (Moench) Voss) in the Great Lakes region. Trees were felled at one northwestern Wisconsin site in a preliminary study in 1997 and at 10 sites throughout northern Wisconsin, Minnesota, and Michigan in 1998. Fungal isolations were made from beetles...
William P. Shepherd; Brian T. Sullivan; Richard A. Goyer; Kier D. Klepzig
We measured electrophysiological responses in the antennae of two predaceous hister beetles, Platysoma parallelum and Plegaderus transversus, exposes to racemic mixtures of primary aggregation pheromones of scolytid bark beetle prey, ipsenol, ipsdienol, and frontalin. No significant differences were found for either histerid...
Mackay, D. S.; Ewers, B. E.; Peckham, S. D.; Savoy, P.; Reed, D. E.; Frank, J. M.
Widespread epidemics of forest-damaging insects have severe implications for the interconnections between water and ecosystem processes under present-day climate. How these systems respond to future climates is highly uncertain, and so there is a need for a better understanding of the effects of such disturbances on plant hydraulics, and the consequent effects on ecosystem processes. Moreover, large-scale manifestations of such disturbances require scaling knowledge obtained from individual trees or stands up to a regional extent. This requires a conceptual framework that integrates physical and biological processes that are immutable and scalable. Indeed, in Western North America multiple conifer species have been impacted by the bark beetle epidemic, but the prediction of such widespread outbreaks under changing environmental conditions must be generalized from a relatively small number of ground-based observations. Using model-data fusion we examine the fundamental principles that drive ecological and hydrological responses to bark beetles infestation from individuals to regions. The study includes a mid-elevation (2750 m a.s.l) lodgepole pine forest and higher (3190 m a.s.l.) elevation Engelmann spruce - fir forest in southern Wyoming. The study included a suite of observations, comprising leaf gas exchange, non-structural carbon (NSC), plant hydraulics, including sap flux transpiration (E), vulnerability to cavitation, leaf water potentials, and eddy covariance, were made pre-, during-, and post-disturbance, as the bark beetle infestation moved through these areas. Numerous observations tested hypotheses generated by the Terrestrial Regional Ecosystem Exchange Simulator (TREES), which integrates soil hydraulics and dynamic tree hydraulics (cavitation) with canopy energy and gas exchange, and operates at scales from individuals to landscapes. TREES accurately predicted E and NSC dynamics among individuals spanning pre- and post-disturbance periods, with the 95
Moser, John C.; Konrad, Heino; Blomquist, Stacy R.; Kirisits, Thomas
Dutch elm disease (DED) is a destructive vascular wilt disease of elm ( Ulmus) trees caused by the introduced Ascomycete fungus Ophiostoma novo-ulmi. In Europe, this DED pathogen is transmitted by elm bark beetles in the genus Scolytus. These insects carry phoretic mites to new, suitable habitats. The aim of this study was to record and quantify conidia and ascospores of O. novo-ulmi on phoretic mites on the three elm bark beetle species Scolytus multistriatus, Scolytus pygmaeus, and Scolytus scolytus. Spores of O. novo-ulmi were found on four of the ten mite species phoretic on Scolytus spp. These included Elattoma fraxini, Proctolaelaps scolyti, Pseudotarsonemoides eccoptogasteri, and Tarsonemus crassus. All four species had spores attached externally to their body surfaces. However, T. crassus carried most spores within its sporothecae, two paired pocket-like structures adapted for fungal transmission. Individuals of Pr. scolyti also had O. novo-ulmi conidia and ascospores frequently in their digestive system, where they may remain viable. While E. fraxini and P. eccoptogasteri rarely had spores attached to their bodies, large portions of Pr. scolyti and T. crassus carried significant numbers of conidia and/or ascospores of O. novo-ulmi. P. scolyti and T. crassus, which likely are fungivores, may thus contribute to the transmission of O. novo-ulmi, by increasing the spore loads of individual Scolytus beetles during their maturation feeding on twigs of healthy elm trees, enhancing the chance for successful infection with the pathogen. Only S. scolytus, which is the most efficient vector of O. novo-ulmi in Europe, carried high numbers of Pr. scolyti and T. crassus, in contrast to S. multistriatus and S. pygmaeus, which are known as less efficient vectors. The high efficiency of S. scolytus in spreading Dutch elm disease may be partly due to its association with these two mites and the hyperphoretic spores of O. novo-ulmi they carry.
Schiebe, Christian; Hammerbacher, Almuth; Birgersson, Göran; Witzell, Johanna; Brodelius, Peter E; Gershenzon, Jonathan; Hansson, Bill S; Krokene, Paal; Schlyter, Fredrik
Secondary attraction to aggregation pheromones plays a central role in the host colonization behavior of the European spruce bark beetle Ips typographus. However, it is largely unknown how the beetles pioneering an attack locate suitable host trees, and eventually accept or reject them. To find possible biomarkers for host choice by I. typographus, we analyzed the chemistry of 58 Norway spruce (Picea abies) trees that were subsequently either (1) successfully attacked and killed, (2) unsuccessfully attacked, or (3) left unattacked. The trees were sampled before the main beetle flight in a natural Norway spruce-dominated forest. No pheromones were used to attract beetles to the experimental trees. To test the trees' defense potential, each tree was treated in a local area with the defense hormone methyl jasmonate (MeJ), and treated and untreated bark were analyzed for 66 different compounds, including terpenes, phenolics and alkaloids. The chemistry of MeJ-treated bark correlated strongly with the success of I. typographus attack, revealing major chemical differences between killed trees and unsuccessfully attacked trees. Surviving trees produced significantly higher amounts of most of the 39 analyzed mono-, sesqui-, and diterpenes and of 4 of 20 phenolics. Alkaloids showed no clear pattern. Differences in untreated bark were less pronounced, where only 1,8-cineole and (-)-limonene were significantly higher in unsuccessfully attacked trees. Our results show that the potential of individual P. abies trees for inducing defense compounds upon I. typographus attack may partly determine tree resistance to this bark beetle by inhibiting its mass attack.
Full Text Available Tree mortality caused by bark beetle infestation has significant effects on the ecology and value of both natural and commercial forests. Therefore, prediction of bark beetle infestations is critical in forest management. Existing predictive models, however, rarely consider the influence of long-term stressors on forest susceptibility to bark beetle infestation. In this study we introduce pre-disturbance spectral trajectories from Landsat Thematic Mapper (TM imagery as an indicator of long-term stress into models of bark beetle infestation together with commonly used environmental predictors. Observations for this study come from forests in the central part of the Šumava Mountains, in the border region between the Czech Republic and Germany, Central Europe. The areas of bark beetle-infested forest were delineated from aerial photographs taken in 1991 and in every year from 1994 to 2000. The environmental predictors represent forest stand attributes (e.g., tree density and distance to the infested forest from previous year and common abiotic factors, such as topography, climate, geology, and soil. Pre-disturbance spectral trajectories were defined by the linear regression slope of Tasseled Cap components (Wetness, Brightness and Greenness calculated from a time series of 16 Landsat TM images across years from 1984 until one year before the bark beetle infestation. Using logistic regression and multimodel inference, we calculated predictive models separately for each single year from 1994 to 2000 to account for a possible shift in importance of individual predictors during disturbance. Inclusion of two pre-disturbance spectral trajectories (Wetness slope and Brightness slope significantly improved predictive ability of bark beetle infestation models. Wetness slope had the greatest predictive power, even relative to environmental predictors, and was relatively stable in its power over the years. Brightness slope improved the model only in the
Huff Hartz, K. E.; Amin, H.; Dodson, C.; Atkins, P. T.; Hallar, G.
Bark beetles are a potentially destructive force in forest ecosytems; however, it is not known how insect attacks affect the atmosphere. Other insects, such as the weevil (Strophosoma melanogrammum) attacks on spruce trees in Denmark, have a significant local effect on monoterpene emissions. In fact, a single weevil induced a three-fold increase in monoterpene emission, and the response lasted for several weeks. Mountain pine bark beetles (Dendroctonus ponderosae) have infested the forests in the vicinity of Storm Peak Laboratory near Steamboat Springs, Colorado. Emissions were sampled from the headspace of bark at the trunk and from the tree branches in the canopy from bark beetle infested and healthy lodgepole pine (Pinus contorta var. latifolia) and Engelmann spruce (Picea engelmannii) trees. The emissions were collected onto scent traps, containing 110 mg of Porapak Q sorbent, using PAS-500 micro air samplers set to a 0.4 mL/min flow rate for two hours. After collection, the scent traps were spiked with a recovery standard, perdeutrated decane, and extracted with 1.5 mL hexanes (in three portions). The analytes in the extracts were separated and detected using gas chromatography/mass spectroscopy. The analytes were identified and quantified using calibration curves from authentic standards, and when authentic standards were not available, the NIST mass spectra library and Adams retention time indices were used. The samples from lodgepole pine trees suggest an enhancement in the 3-carene, beta-phellandrene, and estragole (methyl chavicol) emissions upon bark beetle infestation. The samples from the Engelmann spruce trees suggest an enhancement in the 1,4-cineole, p-cymene, and beta-phellandrene emissions upon bark beetle infestation. A shift in the type and the quantity of VOC emissions due to bark beetle infestation may lead increases in SOA from these forests, since potent SOA precursors are produced.
Chad M. Hoffman; Joel D. McMillin; Carolyn Hull Sieg; Peter Z. Fule
Bark beetles (Coleoptera: Scolytinae) are important biotic agents of conifer mortality in forests of western North America (Furniss and Carolin 1977) and play an important role in the disturbance ecology of these ecosystems (Fettig and others 2007). Bark beetle outbreaks affect subsequent fire behavior in part by influencing the spatial...
Christopher J. Fettig; Christopher J. Hayes; Karen J. Jones; Stephen R. McKelvey; Sylvia L. Mori; Sheri L. Smith
Bark beetles (Coleoptera: Curculionidae, Scolytinae) are commonly recognized as important tree mortality agents in coniferous forests of the western U.S.A.High stand density is consistently associated with bark beetle infestations in western coniferous forests, and therefore, thinning has long been advocated as a...
A recent seven-state survey revealed that the newly invasive banded elm bark beetle, Scolytus schevyrewi, was abundant in areas of Colorado and Wyoming, USA, whereas the long-established European elm bark beetle, S. multistriatus was not as abundant. Behavioral trials were conducted by hanging sm...
Benjamin C. Bright; Andrew T. Hudak; Robert E. Kennedy; Arjan J. H. Meddens
Bark beetle-caused tree mortality affects important forest ecosystem processes. Remote sensing methodologies that quantify live and dead basal area (BA) in bark beetle-affected forests can provide valuable information to forest managers and researchers. We compared the utility of light detection and ranging (lidar) and the Landsat-based detection of trends in...
A.S. Adams; C.R. Currie; Y. Cardoza; K.D. Klepzig; K.F. Raffa
Bark beetles are associated with diverse assemblages of microorganisms, many of which affect their interactions with host plants and natural enemies. We tested how bacterial associates of three bark beetles with various types of host relationships affect growth and reproduction of their symbiotic fungi. Fungi were exposed to volatiles...
Janna C. Lee; Ingrid Aguayo; Ray Aslin; Gail Durham; Shakeeb M. Hamud; Beruce D. Moltzan; A. Steve Munson; Jose F. Negron; Travis Peterson; Iral R. Ragenovich; Jeffrey J. Witcosky; Steven J. Seybold
The invasive European elm bark beetle, Scolytus multistriatus (Marsham), was detected in Massachusetts a century ago, and it now occurs throughout the continental United States and southern Canada. The Asian banded elm bark beetle, Scolytus schevyrewi Semenov, was discovered in the United States in 2003, and now occurs in 28 states...
Rastislav Jakus; Wojciech Grodzki; Marek Jezik; Marcin Jachym
The spread of bark beetle outbreaks in the Tatra Mountains was explored by using both terrestrial and remote sensing techniques. Both approaches have proven to be useful for studying spatial patterns of bark beetle population dynamics. The terrestrial methods were applied on existing forestry databases. Vegetation change analysis (image differentiation), digital...
Linnakoski, Riikka; de Beer, Z Wilhelm; Duong, Tuan A; Niemelä, Pekka; Pappinen, Ari; Wingfield, Michael J
Species of Grosmannia with Leptographium anamorphs include important forest pathogens and agents of blue stain in timber. They are commonly found in association with forest pests, such as bark beetles. During a survey of ophiostomatoid fungi in eastern parts of Finland and neighboring Russia, species belonging to the genus Grosmannia were isolated from 12 different bark beetle species infesting Picea abies and Pinus sylvestris, the most economically important conifers in the region. Identification of these fungi was based on morphology, DNA sequence comparisons for three gene regions and phylogenetic analyses. A total of ten taxa were identified. These belonged to six different species complexes in Grosmannia. The phylogenetic analyses provided an opportunity to redefine the G. galeiformis-, L. procerum-, L. lundbergii-, G. piceiperda-, G. olivacea- and G. penicillata-complexes, and to consider the species emerging from the survey within the context of these complexes. The species included G. galeiformis, G. olivacea, L. chlamydatum, L. lundbergii, L. truncatum and a novel taxon, described here as L. taigense sp. nov. In addition, species closely related to G. cucullata, G. olivaceapini comb. nov., G. piceiperda and L. procerum were isolated but their identity could not be resolved. The overall results indicate that the diversity of Grosmannia species in the boreal forests remains poorly understood and that further studies are needed to clarify the status of several species or species complexes.
Jesse Lee Morris
Full Text Available The recent outbreak of native bark beetles in western North America is unprecedented in severity and scale, at least during the historical period. The aim of this work is to develop a proxy-based methodology to understand how bark beetle disturbances are recorded in lake sediments. Three hypotheses are tested to determine how the ecological impacts of severe spruce beetle (Dendroctonus rufipennis disturbances are recorded following mortality of Engelmann spruce (Picea engelmannii. Outbreaks are hypothesized to: (1 decrease the ratio of spruce to fir pollen; (2 increase soil erosion and mobilize terrestrial C; and (3 leach foliar N, enhancing algal productivity. To test these hypotheses, sediment cores from spruce beetle-affected basins were analyzed for pollen, insect remains, organic and minerogenic content, and isotopic and elemental concentrations. The dataset was tested statistically using generalized linear mixed models (GLMMs to determine if the response variables differed significantly between outbreak and non-outbreak periods.
Amini, Sudabe; Nozari, Jamasb; Mandelshtam, Michail Yu; Knížek, Miloš; Etemad, Vahid; Faccoli, Massimo
Bark and ambrosia beetles from the subfamily Scolytinae are among the most important pests in forests of Northern Iran. During investigations conducted in 2013-2016 in different parts of northern forests, the species Crypturgus cribrellus Reitter, Liparthrum bartschti Mühl, Scolytus varshalovitchi Michalski, Scolytus sulcifrons Rey, Scolytus triarmatus (Eggers) and Trypophloeus granulatus (Ratzeburg) were recorded for the first time in Iran; Trypophloeus and Liparthrum were new genera for Iran. As new host plants we found Zelkova sp. for Scolytus varshalovitchi, Michalski, Populus sp. for Liparthrum bartschti, Mühl, Alnus sp. and Pterocarya fraxinifolia for Taphrorychus lenkoranus Reitter, Pterocarya fraxinifolia for Ernoporicus caucasicus (Lindemann), Carpinus sp. for Pteleobius vittatus (Fabricius), Parrotia persica for Scolytus intricatus (Ratzeburg), Alnus sp. and Pterocarya fraxinifolia for Hypothenemus eruditus (Westwood).
Meirmans, S; Skorping, A; Løyning, M K; Kirkendall, L R
Geographic parthenogenesis has been explained as resulting from parasite pressure (Red Queen hypothesis): several studies have found high degrees of sexuals where the prevalence of parasites is high. However, it is important to address whether prevalence of parasites mirrors risk of infection. We explored geographic parthenogenesis of Ips acuminatus bark beetles and their nematodes. Local climate is crucial for nematode stages outside the host, in spring and summer, and prevalence should thus be associated with those temperatures if prevalence reliably reflects exposure risk across populations. This was the case; however, high prevalence of a virulent nematode species was not associated with many sexuals, whereas highly sexual populations were characterized by high infection risk of benign nematodes. Low virulence of the latter makes Red Queen dynamics unlikely. Geographical patterns of parthenogenesis were instead associated with winter temperature and variance in temperature.
Abdullah, Haidi; Darvishzadeh, Roshanak; Skidmore, Andrew K.; Groen, Thomas A.; Heurich, Marco
The European spruce bark beetle Ips typographus, L. (hereafter bark beetle), causes major economic loss to the forest industry in Europe, especially in Norway Spruce (Picea abies). To minimise economic loss and preclude a mass outbreak, early detection of bark beetle infestation (so-called ;green attack; stage - a period at which trees are yet to show visual signs of infestation stress) is, therefore, a crucial step in the management of Norway spruce stands. It is expected that a bark beetle infestation at the green attack stage affects a tree's physiological and chemical status. However, the concurrent effect on key foliar biochemical such as foliar nitrogen and chlorophyll as well as spectral responses are not well documented in the literature. Therefore, in this study, the early detection of bark beetle green attacks is investigated by examining foliar biochemical and spectral properties (400-2000 nm). We also assessed whether bark beetle infestation affects the estimation accuracy of foliar biochemicals. An extensive field survey was conducted in the Bavarian Forest National Park (BFNP), Germany, in the early summer of 2015 to collect leaf samples from 120 healthy and green attacked trees. The spectra of the leaf samples were measured using an ASD FieldSpec3 equipped with an integrating sphere. Significant differences (p < 0.05) between healthy and infested needle samples were found in the mean reflectance spectra, with the most pronounced differences being observed in the NIR and SWIR regions between 730 and 1370 nm. Furthermore, significant differences (p < 0.05) were found in the biochemical compositions (chlorophyll and nitrogen concentration) of healthy versus green attacked samples. Our results further demonstrate that the estimation accuracy of foliar chlorophyll and nitrogen concentrations, utilising partial least square regression model, was lower for the infested compared to the healthy trees. We show that early stage of infestation reduces not only
Andrew J. McMahan; Alan A. Ager; Helen Maffei; Jane L. Hayes; Eric L. Smith
The Westwide Pine Beetle Model and the Fire and Fuels Extension were used to simulate a mountain pine beetle outbreak under different fuel treatment scenarios on a 173,000 acre landscape on the Deschutes National Forest. The goal was to use these models within ArcFuels to analyze the interacting impacts of bark beetles and management activities on landscape fuel...
Vojtěch, O.; Křenová, Zdeňka; Jakuš, R.
Roč. 19, č. 3 (2013), s. 149-163 ISSN 1211-7420 R&D Projects: GA MŠk(CZ) ED1.1.00/02.0073 Institutional support: RVO:67179843 Keywords : Šumava National Park * mountain spruce forest * species diversity * natural disturbances * rare species Subject RIV: EH - Ecology, Behaviour
Vojtěch, O.; Křenová, Zdeňka; Jakuš, R.
Roč. 19, č. 3 (2013), s. 149-164 ISSN 1211-7420 R&D Projects: GA MŠk(CZ) ED1.1.00/02.0073 Institutional support: RVO:67179843 Keywords : Šumava National Park * mountain spruce forest * species diversity * natural disturbances * rare species Subject RIV: EH - Ecology, Behaviour
Andersson, Martin N; Grosse-Wilde, Ewald; Keeling, Christopher I; Bengtsson, Jonas M; Yuen, Macaire M S; Li, Maria; Hillbur, Ylva; Bohlmann, Jörg; Hansson, Bill S; Schlyter, Fredrik
The European spruce bark beetle, Ips typographus, and the North American mountain pine beetle, Dendroctonus ponderosae (Coleoptera: Curculionidae: Scolytinae), are severe pests of coniferous forests. Both bark beetle species utilize aggregation pheromones to coordinate mass-attacks on host trees, while odorants from host and non-host trees modulate the pheromone response. Thus, the bark beetle olfactory sense is of utmost importance for fitness. However, information on the genes underlying olfactory detection has been lacking in bark beetles and is limited in Coleoptera. We assembled antennal transcriptomes from next-generation sequencing of I. typographus and D. ponderosae to identify members of the major chemosensory multi-gene families. Gene ontology (GO) annotation indicated that the relative abundance of transcripts associated with specific GO terms was highly similar in the two species. Transcripts with terms related to olfactory function were found in both species. Focusing on the chemosensory gene families, we identified 15 putative odorant binding proteins (OBP), 6 chemosensory proteins (CSP), 3 sensory neuron membrane proteins (SNMP), 43 odorant receptors (OR), 6 gustatory receptors (GR), and 7 ionotropic receptors (IR) in I. typographus; and 31 putative OBPs, 11 CSPs, 3 SNMPs, 49 ORs, 2 GRs, and 15 IRs in D. ponderosae. Predicted protein sequences were compared with counterparts in the flour beetle, Tribolium castaneum, the cerambycid beetle, Megacyllene caryae, and the fruit fly, Drosophila melanogaster. The most notable result was found among the ORs, for which large bark beetle-specific expansions were found. However, some clades contained receptors from all four beetle species, indicating a degree of conservation among some coleopteran OR lineages. Putative GRs for carbon dioxide and orthologues for the conserved antennal IRs were included in the identified receptor sets. The protein families important for chemoreception have now been identified in
Miller, Daniel R; Asaro, Chris; Crowe, Christopher M; Duerr, Donald A
In 2006, we examined the flight responses of 43 species of longhorn beetles (Coleoptera: Cerambycidae) to multiple-funnel traps baited with binary lure blends of (1) ipsenol + ipsdienol, (2) ethanol + alpha-pinene, and a quaternary lure blend of (3) ipsenol + ipsdienol + ethanol + alpha-pinene in the southeastern United States. In addition, we monitored responses of Buprestidae, Elateridae, and Curculionidae commonly associated with pine longhorn beetles. Field trials were conducted in mature pine (Pinus pp.) stands in Florida, Georgia, Louisiana, and Virginia. The following species preferred traps baited with the quaternary blend over those baited with ethanol + alpha-pinene: Acanthocinus nodosus (F.), Acanthocinus obsoletus (Olivier), Astylopsis arcuata (LeConte), Astylopsis sexguttata (Say), Monochamus scutellatus (Say), Monochamus titillator (F.) complex, Rhagium inquisitor (L.) (Cerambycidae), Buprestis consularis Gory, Buprestis lineata F. (Buprestidae), Ips avulsus (Eichhoff), Ips calligraphus (Germar), Ips grandicollis (Eichhoff), Orthotomicus caelatus (Eichhoff), and Gnathotrichus materiarus (Fitch) (Curculionidae). The addition ofipsenol and ipsdienol had no effect on catches of 17 other species of bark and wood boring beetles in traps baited with ethanol and a-pinene. Ethanol + alpha-pinene interrupted the attraction of Ips avulsus, I. grandicollis, and Pityophthorus Eichhoff spp. (but not I. calligraphus) (Curculionidae) to traps baited with ipsenol + ipsdienol. Our results support the use of traps baited with a quaternary blend of ipsenol + ipsdienol + ethanol + alpha-pinene for common saproxylic beetles in pine forests of the southeastern United States.
Foster, A.; Shuman, J. K.; Shugart, H. H., Jr.; Negrón, J. F.
Mean annual temperatures in the western United States have increased in the last few decades, and are predicted to continue warming. In the subalpine zone of the Rocky Mountains, this warming is also predicted to increase the frequency and severity of spruce beetle outbreaks. Climate change itself may affect this vegetation, potentially leading to shifts in species compositions. These forests are a crucial part of the US's carbon budget, thus it is important to analyze how climate change and bark beetles in conjunction will affect the biomass and species composition of vegetation in subalpine zone. UVAFME is an individual-based gap model that simulates biomass and species composition of a forest. This model has been quantitatively tested at various Rocky Mountain sites in the Front Range, and has been shown to accurately simulate the vegetation dynamics in the region. UVAFME has been updated with a spruce beetle subroutine that calculates the probability for beetle infestation of each tree on a plot. This probability is based on site, climate, and individual tree characteristics, such as temperature; stand structure; and tree stress level, size, and age. These governing characteristics are based on data from the US Forest Service, and other studies on spruce susceptibility and spruce beetle phenology. UVAFME is then run with multiple climate change and beetle scenarios to determine the net effect of both variables on subalpine vegetation. These results are compared among the different scenarios and to current forest inventory data. We project that increasing temperatures due to climate change will cause an increase in the frequency and severity of spruce beetle outbreaks, leading to a decrease in the biomass and dominance of Engelmann spruce. These results are an important step in understanding the possible futures for the vegetation of subalpine zone in the Rocky Mountains.
Mason, Charles J; Klepzig, Kier D; Kopper, Brian J; Kersten, Philip J; Illman, Barbara L; Raffa, Kenneth F
Conifers possess a suite of physiochemical defenses that protect their subcortical tissues from bark beetle - fungal complexes. These defenses include rapid induction of terpenoids and phenolics at the site of attack. Studies of the distribution, induction, and bioactivity of conifer terpenoids have focused heavily on monoterpenes. We assessed induction of diterpene acids in white spruce (Picea glauca) and red pine (Pinus resinosa) to fungal associates of two bark beetles, and the responses of four spruce beetle (Dendroctonus rufipennis)-associated fungi to three diterpene acids. Constitutive phloem contents differed between species, in that red pine had extremely low concentrations of diterpene acids, whereas white spruce had substantial constitutive levels. Induction differed quantitatively. Both red pine and white spruce exhibited marked increases, but red pine underwent greater increases and achieved higher concentrations than white spruce. Induction also differed qualitatively in that red pine showed lower diversity and fewer compositional changes during induction than white spruce. In red pine,fungal inoculation accompanying wounding elicited greater increases than wounding alone, but in white spruce total concentrations were higher following wounding alone. Spruce beetle fungal symbiont growth varied among species and compounds. Some diterpenes elicited both stimulatory and inhibitory effects on fungi, depending on concentration. All four fungi exhibited higher tolerances compared to those associated with pine bark beetles in previous studies. Variation in tolerances to, and potentially metabolism of, diterpene acids by symbionts may reflect differences in constitutive levels between spruce and pine, and partially explain differences in concentrations achieved during induction.
Kyrre L Kausrud
Full Text Available Bark beetles (Coleoptera: Curculionidae, Scolytinae feed and breed in dead or severely weakened host trees. When their population densities are high, some species aggregate on healthy host trees so that their defences may be exhausted and the inner bark successfully colonized, killing the tree in the process. Here we investigate under what conditions participating with unrelated conspecifics in risky mass attacks on living trees is an adaptive strategy, and what this can tell us about bark beetle outbreak dynamics. We find that the outcome of individual host selection may deviate from the ideal free distribution in a way that facilitates the emergence of tree-killing (aggressive behavior, and that any heritability on traits governing aggressiveness seems likely to exist in a state of flux or cycles consistent with variability observed in natural populations. This may have implications for how economically and ecologically important species respond to environmental changes in climate and landscape (forest structure. The population dynamics emerging from individual behavior are complex, capable of switching between "endemic" and "epidemic" regimes spontaneously or following changes in host availability or resistance. Model predictions are compared to empirical observations, and we identify some factors determining the occurrence and self-limitation of epidemics.
Kausrud, Kyrre L.; Grégoire, Jean-Claude; Skarpaas, Olav; Erbilgin, Nadir; Gilbert, Marius; Økland, Bjørn; Stenseth, Nils Chr.
Bark beetles (Coleoptera: Curculionidae, Scolytinae) feed and breed in dead or severely weakened host trees. When their population densities are high, some species aggregate on healthy host trees so that their defences may be exhausted and the inner bark successfully colonized, killing the tree in the process. Here we investigate under what conditions participating with unrelated conspecifics in risky mass attacks on living trees is an adaptive strategy, and what this can tell us about bark beetle outbreak dynamics. We find that the outcome of individual host selection may deviate from the ideal free distribution in a way that facilitates the emergence of tree-killing (aggressive) behavior, and that any heritability on traits governing aggressiveness seems likely to exist in a state of flux or cycles consistent with variability observed in natural populations. This may have implications for how economically and ecologically important species respond to environmental changes in climate and landscape (forest) structure. The population dynamics emerging from individual behavior are complex, capable of switching between “endemic” and “epidemic” regimes spontaneously or following changes in host availability or resistance. Model predictions are compared to empirical observations, and we identify some factors determining the occurrence and self-limitation of epidemics. PMID:21647433
K. D. Klepzig; B. L. Strom
A commercially available chitosan product, Beyondâ¢, was evaluated for its effects on loblolly pine, Pinus taeda L., responses believed related to bark beetle resistance. Treatments were applied 4 times at approx. 6-wk intervals between May and November 2008. Five treatments were evaluated: ground application (soil drench), foliar application, ground...
Jankowiak, R.; Kolařík, Miroslav; Bilanski,, P.
Roč. 11, OCT 2014 (2014), s. 71-79 ISSN 1754-5048 R&D Projects: GA ČR(CZ) GAP506/11/2302 Institutional support: RVO:61388971 Keywords : Insect-fungus interactions * Bark beetles * Ectosymbiosis Subject RIV: EE - Microbiology, Virology Impact factor: 2.929, year: 2014
Jesse L Morris; Stuart Cottrell; Christopher J Fettig; R. Justin DeRose; Katherine M Mattor; Vachel A Carter; Jennifer Clear; Jessica Clement; Winslow D Hansen; Jeffrey A Hicke; Philip E Higuera; Alistair WR Seddon; Heikki Seppä; Rosemary L Sherriff; John D Stednick; Steven J Seybold
Due to recent outbreaks of native bark beetles, forest ecosystems have experienced substantial changes in landscape structure and function, which also affect nearby human populations. As a result, land managers have been tasked with sustaining ecosystem services in impacted areas by considering the best available science, public perceptions, and monitoring data to...
In the 1970-80s, vapors of the common conifer tree monoterpenes, myrcene and a-pinene, were shown to serve as precursors of ipsenol, ipsdienol and cis-verbenol, aggregation pheromone components of Ips paraconfusus. A paradigm developed that Ips bark beetles utilize pre-formed monoterpene precursors ...
David E. Reed; Brent E. Ewers; Elise Pendall; John Frank; Robert Kelly
Insect outbreaks are major disturbances that affect a land area similar to that of forest fires across North America. The recent mountain pine bark beetle (Dendroctonus ponderosae) outbreak and its associated blue stain fungi (Grosmannia clavigera) are impacting water partitioning processes of forests in the Rocky Mountain region as the spatially heterogeneous...
S. McElwey; J. F. Negron; J. Withrow
Scolytus schevyrewi Semenov, the banded elm bark beetle, was first detected in North America in April 2003 in Colorado and Utah by the Rapid Detection and Response Pilot Project sponsored by APHIS and USDA Forest Service, Forest Health Protection. It was captured in Lindgren funnel traps baited with a-pinene, ethanol, and the Ips typographus...
Jana C. Lee; Jose F. Negron; Sally J. McElwey; Livy Williams; Jeffrey J. Witcosky; John B. Popp; Steven J. Seybold
The banded elm bark beetle, Scolytus schevyrewi Semenov (Coleoptera: Scolytidae), native to Asia, was detected in the United States in 2003, and as of 2011 it is known to occur in 28 states and four Canadian provinces. S. schevyrewi infests the same elm (Ulmus spp.) hosts as the longestablished invasive...
Christopher J. Fettig
The future looks bright for the development and use of semiochemical-based tools in forests, particularly in remote and sensitive areas where other management techniques (e.g., the use of insecticides) may not be appropriate. This editorial provides an concise overview of chemical ecology and management of bark beetles in western coniferous forests.
Steven L. Edburg; Jeffrey A. Hicke; David M. Lawrence; Peter E. Thornton
Insect outbreaks are major ecosystem disturbances, affecting a similar area as forest fires annually across North America. Tree mortality caused by bark beetle outbreaks alters carbon cycling in the first several years following the disturbance by reducing stand-level primary production and by increasing the amount of dead organic matter available for decomposition....
Full Text Available In the period from 1992 to 2013, more than 3.8 million m3 of spruce wood from an area of 55 thousand ha of forests in the Kysuce region (Western Carpathians was affected by bark beetles. This region has had the highest volume of salvage fellings in Slovakia. While before 1991, bark-beetle outbreak usually occurred after snow and wind disturbances, since 1992 they have occurred in the years with extremely warm and dry growing seasons and the years following them. These years were also characterised by high volumes of wood affected by honey fungus (Armillaria spp., which only rarely took part in the calamities before 1992. Extreme deterioration of the situation occurred after 2003. In fragmented and sparse stands, the volume of wood damaged by wind increased. Artificial origin of spruce stands, their high occurrence, high age and even-agedness are likely pre-disposing factors of spruce forest decline. Bark beetles have become the most important factor of spruce decline. The most important factors driving the bark beetle attack on forest stands in the period 1973–2013 were the amount of unprocessed wood in the previous year; the amount of wood affected by honey fungus, precipitation total, and average temperature in the current growing season. Another important factor that complicated the situation was also the inferior quality of forest management.
Chad Hoffman; Russell Parsons; Penny Morgan; Ruddy Mell
The purpose of this study is to investigate how varying amounts of MPB-induced tree mortality affects the amount of crown fuels consumed and the fire intensity across a range of lodgepole pine stands of different tree density and spatial arrangements during the early stages of a bark beetle outbreak. Unlike past studies which have relied on semi-empirical or empirical...
T. L. Shore; A. Fall; W. G. Riel; J. Hughes; M. Eng
The objective of our paper is to provide practitioners with suggestions on how to select appropriate methods for risk assessment of bark beetle infestations at the landscape scale in order to support their particular management decisions and to motivate researchers to refine novel risk assessment methods. Methods developed to assist and inform management decisions for...
Viktorinová, I.; Kučerová, Lucie; Böhmová, Marta; Henry, I.; Jindra, Marek; Doležal, Petr; Žurovcová, Martina; Žurovec, Michal
Roč. 77, č. 4 (2011), s. 179-198 ISSN 0739-4462 EU Projects: European Commission(CZ) FP7/2007-2013 Program:FP7 Institutional research plan: CEZ:AV0Z50070508 Keywords : bark beetle * intron polymorphism * α-amylase Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.361, year: 2011
Michael J. Clifford; Monique E. Rocca; Robert Delph; Paulette L. Ford; Neil S. Cobb
The current drought and ensuing bark beetle outbreaks during 2002 to 2004 in the Southwest have greatly increased tree mortality in pinyon-juniper woodlands. We studied causes and consequences of the drought-induced mortality. First, we tested the paradigm that high stand densities in pinyon-juniper woodlands would increase tree mortality. Stand densities did not...
Roč. 6, č. 2 (2016), s. 108-113 ISSN 1805-0174 R&D Projects: GA MŠk(CZ) LO1415 Institutional support: RVO:67179843 Keywords : bark beetle * climate change * forest management * hydrological cycle Subject RIV: EH - Ecology, Behaviour
Hais, M.; Wild, Jan; Berec, Luděk; Brůna, Josef; Kennedy, J.; Braaten, J.; Brož, Z.
Roč. 8, č. 8 (2016), s. 1-22 ISSN 2072-4292 R&D Projects: GA MŠk(CZ) LD15158 Institutional support: RVO:67985939 ; RVO:60077344 Keywords : forest disturbance * spectral trajectories * bark beetle * Landsat Subject RIV: GK - Forestry; EH - Ecology, Behaviour (BC-A) Impact factor: 3.244, year: 2016
Kevin Chase; Dave Kelly; Andrew M. Liebhold; Martin K.-F. Bader; Eckehard G. Brockerhoff
Dispersal and host detection are behaviours promoting the spread of invading populations in a landscape matrix. In fragmented landscapes, the spatial arrangement of habitat structure affects the dispersal success of organisms. The aim of the present study was to determine the long distance dispersal capabilities of two non-native pine bark beetles (Hylurgus...
Barbara J. Bentz; Jacques Regniere; Christopher J. Fettig; E. Matthew Hansen; Jane L. Hayes; Jeffrey A. Hicke; Rick G. Kelsey; Jose F. Negron; Steven J. Seybold
Climatic changes are predicted to significantly affect the frequency and severity of disturbances that shape forest ecosystems. We provide a synthesis of climate change effects on native bark beetles, important mortality agents of conifers in western North America. Because of differences in temperature-dependent life-history strategies, including cold-induced mortality...
Moravec, Ivo; Cudlín, Pavel; Polák, T.; Havlíček, František
Roč. 8, - (2002), s. 255-264 ISSN 1211-7420 R&D Projects: GA MŠk OK 389 Institutional research plan: CEZ:AV0Z6087904 Keywords : bark beetle infestation * crown status * Picea abies Subject RIV: GK - Forestry
Richard H. Smith
Xylem resin of Pinaceae is closely linked with their resistance and suseptibility to tree-killing bark beetles. This review of the literature on attacking adults suggests that all three resistance mechanisms proposed by Painter -- preference, antibiosis, and tolerance -- are active in this relationship: preference by attraction, repellency, and synergism; antibiosis...
Kaňa, Jiří; Tahovská, K.; Kopáček, Jiří
Roč. 113, 1-3 (2013), s. 369-383 ISSN 0168-2563 R&D Projects: GA AV ČR(CZ) KJB600960907 Institutional support: RVO:60077344 Keywords : bark beetle infestation * soil nutrient availability * soil sorption complex Subject RIV: DJ - Water Pollution ; Quality Impact factor: 3.730, year: 2013
Rhoades, C.; Hubbard, R. M.; Elder, K.
Biogeochemical responses and ecosystem recovery from bark beetle outbreaks are influenced by pre-disturbance forest structure and composition and catchment conditions. Over the past decade, the mountain pine bark beetle (Dendroctonus ponderosae) has killed mature lodgepole pine (Pinus contorta) trees at the Fraser Experimental Forest and throughout the Colorado Rockies. Here we compare stream nitrogen (N) concentrations during the outbreak with data from the previous two decades in four research catchments with distinct forest management history, stand age structure and watershed characteristics. In two old growth forest catchments, stream nitrate concentrations were significantly higher during the infestation in the snowmelt and base flow seasons. The beetle infestation elevated nitrate export 43 and 74% in these two catchments though the amounts of N released in streamwater (0.04 and 0.15 kg N ha-1) were beetle infestation in two catchments comprised of a mixture of second-growth (30-60 year old) and old-growth (250-350 year old) forest stands where the density of residual live trees was higher on average. Mortality of overstory trees from bark beetles has stimulated the growth of understory and overstory trees with likely consequences for nutrient demand and retention in recovering forests.
Jordal, Bjarte H; Kambestad, Marius
A comprehensive DNA barcoding library is very useful for rapid identification and detection of invasive pest species. We tested the performance of species identification in the economically most damaging group of wood-boring insects - the bark and ambrosia beetles - with particular focus on broad geographical sampling across the boreal Palearctic forests. Neighbour-joining and Bayesian analyses of cytochrome oxidase I (COI) sequences from 151 species in 40 genera revealed high congruence between morphology-based identification and sequence clusters. Inconsistencies with morphological identifications included the discovery of a likely cryptic Nearctic species of Dryocoetes autographus, the possible hybrid origin of shared mitochondrial haplotypes in Pityophthorus micrographus and P. pityographus, and a possible paraphyletic Xyleborinus saxeseni. The first record of Orthotomicus suturalis in North America was confirmed by DNA barcoding. The mitochondrial data also revealed consistent divergence across the Palearctic or Holarctic, confirmed in part by data from the large ribosomal subunit (28S). Some populations had considerable variation in the mitochondrial barcoding marker, but were invariant in the nuclear ribosomal marker. These findings must be viewed in light of the high number of nuclear insertions of mitochondrial DNA (NUMTs) detected in eight bark beetle species, suggesting the possible presence of additional cryptic NUMTs. The occurrence of paralogous COI copies, hybridization or cryptic speciation demands a stronger focus on data quality assessment in the construction of DNA barcoding databases. © 2013 John Wiley & Sons Ltd.
John A. Byers
Full Text Available Previous studies and data presented here suggest that odors from healthy host Scotch pine (Pinus sylvestris and nonhost Norway spruce (Picea abies, as well as major monoterpenes of these trees at natural release rates, significantly reduce the attraction of flying bark beetles, Pityogenes bidentatus, of both sexes to their aggregation pheromone components grandisol and cis-verbenol in the field, as tested by slow rotation of trap pairs. In contrast, P. bidentatus males and females walking in an open-arena olfactometer in the laboratory did not avoid monoterpene vapors at release rates spanning several orders of magnitude in combination with aggregation pheromone. The bark beetle may avoid monoterpenes when flying as a mechanism for avoiding nonhost species, vigorous and thus unsuitable host trees, as well as harmful resinous areas of hosts. Inhibition of this flight avoidance response in beetles after landing would allow them to initiate, or to find and enter, gallery holes with high monoterpene vapor concentrations in order to feed and reproduce.
Lahr, Eleanor C; Krokene, Paal
Bark beetles and associated fungi are among the greatest natural threats to conifers worldwide. Conifers have potent defenses, but resistance to beetles and fungal pathogens may be reduced if tree stored resources are consumed by fungi rather than used for tree defense. Here, we assessed the relationship between tree stored resources and resistance to Ceratocystis polonica, a phytopathogenic fungus vectored by the spruce bark beetle Ips typographus. We measured phloem and sapwood nitrogen, non-structural carbohydrates (NSC), and lipids before and after trees were attacked by I. typographus (vectoring C. polonica) or artificially inoculated with C. polonica alone. Tree resistance was assessed by measuring phloem lesions and the proportion of necrotic phloem around the tree's circumference following attack or inoculation. While initial resource concentrations were unrelated to tree resistance to C. polonica, over time, phloem NSC and sapwood lipids declined in the trees inoculated with C. polonica. Greater resource declines correlated with less resistant trees (trees with larger lesions or more necrotic phloem), suggesting that resource depletion may be caused by fungal consumption rather than tree resistance. Ips typographus may then benefit indirectly from reduced tree defenses caused by fungal resource uptake. Our research on tree stored resources represents a novel way of understanding bark beetle-fungal-conifer interactions.
Eleanor C Lahr
Full Text Available Bark beetles and associated fungi are among the greatest natural threats to conifers worldwide. Conifers have potent defenses, but resistance to beetles and fungal pathogens may be reduced if tree stored resources are consumed by fungi rather than used for tree defense. Here, we assessed the relationship between tree stored resources and resistance to Ceratocystis polonica, a phytopathogenic fungus vectored by the spruce bark beetle Ips typographus. We measured phloem and sapwood nitrogen, non-structural carbohydrates (NSC, and lipids before and after trees were attacked by I. typographus (vectoring C. polonica or artificially inoculated with C. polonica alone. Tree resistance was assessed by measuring phloem lesions and the proportion of necrotic phloem around the tree's circumference following attack or inoculation. While initial resource concentrations were unrelated to tree resistance to C. polonica, over time, phloem NSC and sapwood lipids declined in the trees inoculated with C. polonica. Greater resource declines correlated with less resistant trees (trees with larger lesions or more necrotic phloem, suggesting that resource depletion may be caused by fungal consumption rather than tree resistance. Ips typographus may then benefit indirectly from reduced tree defenses caused by fungal resource uptake. Our research on tree stored resources represents a novel way of understanding bark beetle-fungal-conifer interactions.
Thomas DeGomez; Thomas Kolb; Sabrina Kleinman; Kelly Williams
Fire-damaged trees that otherwise would have survived can be killed by bark beetles (McCullough and others 1998, McHugh and others 2003). Wallin and others (2008) found that fire weakens a treeâs defense against bark beetles. An unacceptable level of tree mortality may occur after a controlled burn as a result of weakened tree defenses (Sullivan and others 2003)....
C Rikard Unelius
Full Text Available Conifer feeding bark beetles (Coleoptera, Curculionidae, Scolytinae pose a serious economic threat to forest production. Volatiles released by non-host angiosperm plants (so called non-host volatiles, NHV have been shown to reduce the risk of attack by many bark beetle species, including the European spruce bark beetle, Ips typographus. However, the most active blend for I. typographus, containing three green leaf volatiles (GLVs in addition to the key compounds trans-conophthorin (tC and verbenone, has been considered too expensive for use in large-scale management. To lower the cost and improve the applicability of NHV, we aim to simplify the blend without compromising its anti-attractant potency. Since the key compound tC is expensive in pure form, we also tested a crude version: technical grade trans-conophthorin (T-tC. In another attempt to find a more cost effective substitute for tC, we evaluated a more readily synthesized analog: dehydro-conophthorin (DHC. Our results showed that 1-hexanol alone could replace the three-component GLV blend containing 1-hexanol, (3Z-hexen-1-ol, and (2E-hexen-1-ol. Furthermore, the release rate of tC could be reduced from 5 mg/day to 0.5 mg/day in a blend with 1-hexanol and (--verbenone without compromising the anti-attractant activity. We further show that T-tC was comparable with tC, whereas DHC was a less effective anti-attractant. DHC also elicited weaker physiological responses in the tC-responding olfactory receptor neuron class, providing a likely mechanistic explanation for its weaker anti-attractive effect. Our results suggest a blend consisting of (--verbenone, 1-hexanol and technical trans-conophthorin as a cost-efficient anti-attractant for forest protection against I. typographus.
Unelius, C. Rikard; Schiebe, Christian; Bohman, Björn; Andersson, Martin N.; Schlyter, Fredrik
Conifer feeding bark beetles (Coleoptera, Curculionidae, Scolytinae) pose a serious economic threat to forest production. Volatiles released by non-host angiosperm plants (so called non-host volatiles, NHV) have been shown to reduce the risk of attack by many bark beetle species, including the European spruce bark beetle, Ips typographus. However, the most active blend for I. typographus, containing three green leaf volatiles (GLVs) in addition to the key compounds trans-conophthorin (tC) and verbenone, has been considered too expensive for use in large-scale management. To lower the cost and improve the applicability of NHV, we aim to simplify the blend without compromising its anti-attractant potency. Since the key compound tC is expensive in pure form, we also tested a crude version: technical grade trans-conophthorin (T-tC). In another attempt to find a more cost effective substitute for tC, we evaluated a more readily synthesized analog: dehydro-conophthorin (DHC). Our results showed that 1-hexanol alone could replace the three-component GLV blend containing 1-hexanol, (3Z)-hexen-1-ol, and (2E)-hexen-1-ol. Furthermore, the release rate of tC could be reduced from 5 mg/day to 0.5 mg/day in a blend with 1-hexanol and (–)-verbenone without compromising the anti-attractant activity. We further show that T-tC was comparable with tC, whereas DHC was a less effective anti-attractant. DHC also elicited weaker physiological responses in the tC-responding olfactory receptor neuron class, providing a likely mechanistic explanation for its weaker anti-attractive effect. Our results suggest a blend consisting of (–)-verbenone, 1-hexanol and technical trans-conophthorin as a cost-efficient anti-attractant for forest protection against I. typographus. PMID:24454855
Kautz, Markus; Imron, Muhammad Ali; Dworschak, Kai; Schopf, Reinhard
Dispersal is a key process in the response of insect populations to rapidly changing environmental conditions. Variability among individuals, regarding the timing of dispersal initiation and travelled distance from source, is assumed to contribute to increased population success through risk spreading. However, experiments are often limited in studying complex dispersal interactions over space and time. By applying a local-scaled individual-based simulation model we studied dispersal and emerging infestation patterns in a host - bark beetle system (Picea abies - Ips typgraphus). More specifically, we (i) investigated the effect of individual variability in beetle physiology (flight capacity) and environmental heterogeneity (host susceptibility level) on population-level dispersal success, and (ii) elucidated patterns of spatial and/or temporal variability in individual dispersal success, host selectivity, and the resulting beetle density within colonized hosts in differently susceptible environments. Individual variability in flight capacity of bark beetles causes predominantly positive effects on population-level dispersal success, yet these effects are strongly environment-dependent: Variability is most beneficial in purely resistant habitats, while positive effects are less pronounced in purely susceptible habitats, and largely absent in habitats where host susceptibility is spatially scattered. Despite success rates being highest in purely susceptible habitats, scattered host susceptibility appeared most suitable for dispersing bark beetle populations as it ensures population spread without drastically reducing success rates. At the individual level, dispersal success generally decreases with distance to source and is lowest in early flight cohorts, while host selectivity increased and colonization density decreased with increasing distance across all environments. Our modelling approach is demonstrated to be a powerful tool for studying movement ecology in
Durand, Audrey-Anne; Bergeron, Amélie; Constant, Philippe; Buffet, Jean-Philippe; Déziel, Eric; Guertin, Claude
Many bark beetles belonging to the Dendroctonus genus carry bacterial and fungal microbiota, forming a symbiotic complex that helps the insect to colonize the subcortical environment of the host tree. However, the biodiversity of those bacteria at the surface of the cuticle or inside the body parts of bark beetles is not well established. The aim of this study was to characterize the bacterial microbiome associated with the eastern larch beetle, Dendroctonus simplex, using bacterial 16S rRNA gene pyrosequencing. The ecto- and endomicrobiome and the subcortical galleries were investigated. Several bacterial genera were identified, among which Pseudomonas, Serratia and Yersinia are associated with the surface of the beetle cuticle, and genera belonging to Enterobacteriaceae and Gammaproteobacteria with the interior of the insect body. The index of dissimilarity indicates that the bacterial microbiome associated with each environment constitutes exclusive groups. These results suggest the presence of distinct bacterial microbiota on the surface of the cuticle and the interior of D. simplex body. Additionally, the bacterial diversity identified in the galleries is substantially different from the ectomicrobiome, which could indicate a selection by the insect. This study reports for the first time the identification of the eastern larch beetle microbiome.
French, J.R.J.; Robinson, P.J.
Irradiating elm billets with gamma rays had a significant effect in reducing the attractancy of these billets to inflight adults of the smaller elm bark beetle Scolytus multistriatus (Marsham). The temperature at which the fresh billets were stored prior to the beetle exposure had little effect. Irradiated billets, irrespective of storage temperature, had significantly fewer holes than the freshly cut billets. There were significant differences associated with the location of the billets in the field, but these differences were smaller than those associated with irradiation. (orig.) [de
Fei Chen; Guo Zhang; Michael Barlage; Ying Zhang; Jeffrey A. Hicke; Arjan Meddens; Guangsheng Zhou; William J. Massman; John Frank
Bark beetle outbreaks have killed billions of trees and affected millions of hectares of forest during recent decades. The objective of this study was to quantify responses of surface energy and hydrologic fluxes 2-3 yr following a spruce beetle outbreak using measurements and modeling. The authors used observations at the Rocky Mountains Glacier Lakes Ecosystem...
John S. Hard; Ken P. Zogas
We examined old bark lesions on Lutz spruce in young stands on the Kenai Peninsula, Alaska, to determine their cause. Distribution of these lesions along lower stems was similar to the distribution of spruce beetle attacks during epidemics. These lesions apparently resulted from unsuccessful attacks by spruce beetles during the late 1980s and early 1990s and appear to...
US Forest service, Northeastern Area, State & Private Forestry
Discovery: An overwintering colony of adult Red-haired Bark Beetles (Hylurgus ligniperda Fabricius) was discovered in November 2000 near Rochester, New York. These European beetles were found during an evaluation of white pine root decline in a Christmas tree plantation. Hylurgus ligniperda was intercepted 169 times at ports of entry in the United States between 1985...
S. Kim; T.C. Harrington; J. C. Lee; S. J. Seybold
The redhaired pine bark beetle Hylurgus ligniperda (F.) is native to Europe but was discovered in Los Angeles, California, in 2003. This root- and stump-feeding beetle is a common vector of Ophiostomatales, which are potential tree pathogens or causes of blue stain of conifer sapwood. In this study Ophiostomatales were isolated on a...
Benjamin C. Bright; Andrew T. Hudak; Robert McGaughey; Hans-Erik Andersen; Jose Negron
Bark beetle outbreaks have killed large numbers of trees across North America in recent years. Lidar remote sensing can be used to effectively estimate forest biomass, but prediction of both live and dead standing biomass in beetle-affected forests using lidar alone has not been demonstrated. We developed Random Forest (RF) models predicting total, live, dead, and...
Arjan J. H. Meddens; Jeffrey A. Hicke; Lee A. Vierling; Andrew T. Hudak
Bark beetles cause significant tree mortality in coniferous forests across North America. Mapping beetle-caused tree mortality is therefore important for gauging impacts to forest ecosystems and assessing trends. Remote sensing offers the potential for accurate, repeatable estimates of tree mortality in outbreak areas. With the advancement of multi-temporal disturbance...
Schwilk, Dylan W.; Knapp, Eric E.; Ferrenberg, Scott; Keeley, Jon E.; Caprio, Anthony C.
Over the last century, fire exclusion in the forests of the Sierra Nevada has allowed surface fuels to accumulate and has led to increased tree density. Stand composition has also been altered as shade tolerant tree species crowd out shade intolerant species. To restore forest structure and reduce the risk of large, intense fires, managers have increasingly used prescription burning. Most fires prior to EuroAmerican settlement occurred during the late summer and early fall and most prescribed burning has taken place during the latter part of this period. Poor air quality and lack of suitable burn windows during the fall, however, have resulted in a need to conduct more prescription burning earlier in the season. Previous reports have suggested that burning during the time when trees are actively growing may increase mortality rates due to fine root damage and/or bark beetle activity. This study examines the effects of fire on tree mortality and bark beetle attacks under prescription burning during early and late season. Replicated early season burn, late season burn and unburned control plots were established in an old-growth mixed conifer forest in the Sierra Nevada that had not experienced a fire in over 120 years. Although prescribed burns resulted in significant mortality of particularly the smallest tree size classes, no difference between early and late season burns was detected. Direct mortality due to fire was associated with fire intensity. Secondary mortality due to bark beetles was not significantly correlated with fire intensity. The probability of bark beetle attack on pines did not differ between early and late season burns, while the probability of bark beetle attack on firs was greater following early season burns. Overall tree mortality appeared to be primarily the result of fire intensity rather than tree phenology at the time of the burns. Early season burns are generally conducted under higher fuel moisture conditions, leading to less fuel
Farská, Jitka; Prejzková, Kristýna; Starý, Josef; Rusek, Josef
Roč. 29, č. 6 (2014), s. 1087-1096 ISSN 0912-3814 R&D Projects: GA ČR GA526/03/1259; GA ČR GAP504/12/1218; GA MŠk LC06066 Grant - others:GAJU(CZ) 143/2010/P Institutional support: RVO:60077344 Keywords : bark beetle * Collembola * disturbance * Oribatida * spruce Subject RIV: EH - Ecology, Behaviour Impact factor: 1.296, year: 2014
Seidl, Rupert; Rammer, Werner
Growing evidence suggests that climate change could substantially alter forest disturbances. Interactions between individual disturbance agents are a major component of disturbance regimes, yet how interactions contribute to their climate sensitivity remains largely unknown. Here, our aim was to assess the climate sensitivity of disturbance interactions, focusing on wind and bark beetle disturbances. We developed a process-based model of bark beetle disturbance, integrated into the dynamic forest landscape model iLand (already including a detailed model of wind disturbance). We evaluated the integrated model against observations from three wind events and a subsequent bark beetle outbreak, affecting 530.2 ha (3.8 %) of a mountain forest landscape in Austria between 2007 and 2014. Subsequently, we conducted a factorial experiment determining the effect of changes in climate variables on the area disturbed by wind and bark beetles separately and in combination. iLand was well able to reproduce observations with regard to area, temporal sequence, and spatial pattern of disturbance. The observed disturbance dynamics was strongly driven by interactions, with 64.3 % of the area disturbed attributed to interaction effects. A +4 °C warming increased the disturbed area by +264.7 % and the area-weighted mean patch size by +1794.3 %. Interactions were found to have a ten times higher sensitivity to temperature changes than main effects, considerably amplifying the climate sensitivity of the disturbance regime. Disturbance interactions are a key component of the forest disturbance regime. Neglecting interaction effects can lead to a substantial underestimation of the climate change sensitivity of disturbance regimes.
Wong, Carmen M; Daniels, Lori D
Novel forest decline is increasing due to global environmental change, yet the causal factors and their interactions remain poorly understood. Using tree ring analyses, we show how climate and multiple biotic factors caused the decline of whitebark pine (Pinus albicaulis) in 16 stands in the southern Canadian Rockies. In our study area, 72% of whitebark pines were dead and 18% had partially dead crowns. Tree mortality peaked in the 1970s; however, the annual basal area increment of disturbed trees began to decline significantly in the late 1940s. Growth decline persisted up to 30 years before trees died from mountain pine beetle (Dendroctonus ponderosae), Ips spp. bark beetles or non-native blister rust pathogen (Cronartium ribicola). Climate-growth relations varied over time and differed among the healthy and disturbed subpopulations of whitebark pine. Prior to the 1940s, cool temperatures limited the growth of all subpopulations. Growth of live, healthy trees became limited by drought during the cool phase (1947 -1976) of the Pacific Decadal Oscillation (PDO) and then reverted to positive correlations with temperature during the subsequent warm PDO phase. In the 1940s, the climate-growth relations of the disturbed subpopulations diverged from the live, healthy trees with trees ultimately killed by mountain pine beetle diverging the most. We propose that multiple factors interacted over several decades to cause unprecedented rates of whitebark pine mortality. Climatic variation during the cool PDO phase caused drought stress that may have predisposed trees to blister rust. Subsequent decline in snowpack and warming temperatures likely incited further climatic stress and with blister rust reduced tree resistance to bark beetles. Ultimately, bark beetles and blister rust contributed to tree death. Our findings suggest the complexity of whitebark pine decline and the importance of considering multiway drought-disease-insect interactions over various timescales when
Hicke, J. A.; Edburg, S. L.; Meddens, A. J.
Insect outbreaks are major forest disturbances, altering carbon and nitrogen fluxes through growth reductions and/or tree mortality. In western North America, bark beetles have killed trees over millions of hectares. Here we report on several studies that increase our understanding of the biogeochemical impacts of bark beetle epidemics. We modified the Community Land Model to simulate these disturbances, then ran the model for a range of hypothetical, realistic outbreak conditions to explore variability in impacts. We find significant differences in the responses of carbon and nitrogen based on the severity of the outbreak, the timing of snagfall, and the time since attack. Given the importance of identifying the number of trees killed within a study region for accurately quantifying impacts, we have developed a database of mortality in the western US and British Columbia for 1997-2009. We combined this database with spatially explicit maps of carbon stocks to estimate the amount of carbon in killed trees. We also used this database to drive CLM to quantify changes in biogeochemical stocks and fluxes. We find that in some regions, bark beetle-killed trees accounted for over 30% of the carbon stocks, whereas in other areas, the number of killed trees was low. Effects on net carbon fluxes in outbreak regions were significant, with fluxes switching from sinks to sources.
Kane, Jeffrey M; Kolb, Thomas E
The relative importance of growth and defense to tree mortality during drought and bark beetle attacks is poorly understood. We addressed this issue by comparing growth and defense characteristics between 25 pairs of ponderosa pine (Pinus ponderosa) trees that survived and trees that died from drought-associated bark beetle attacks in forests of northern Arizona, USA. The three major findings of our research were: (1) xylem resin ducts in live trees were >10% larger (diameter), >25% denser (no. of resin ducts mm(-2)), and composed >50% more area per unit ring growth than dead trees; (2) measures of defense, such as resin duct production (no. of resin ducts year(-1)) and the proportion of xylem ring area to resin ducts, not growth, were the best model parameters of ponderosa pine mortality; and (3) most correlations between annual variation in growth and resin duct characteristics were positive suggesting that conditions conducive to growth also increase resin duct production. Our results suggest that trees that survive drought and subsequent bark beetle attacks invest more carbon in resin defense than trees that die, and that carbon allocation to resin ducts is a more important determinant of tree mortality than allocation to radial growth.
Klingeman, William E; Bray, Alicia M; Oliver, Jason B; Ranger, Christopher M; Palmquist, Debra E
Knowledge about which bark and ambrosia beetle species are active and at what heights in black walnut canopies is not well understood. Neither is the role of these beetles in spreading Thousand Cankers Disease. To assist with future planned research, which will assess the extent to which these beetle species are associated with Geosmithia morbida Kolařík, Freeland, Utley, and Tisserat (Ascomycota: Hypocreales: Bionectriaceae), experiments were undertaken to monitor bark and ambrosia beetles in urban landscapes and parks in Tennessee between 2011 and 2013. Within mature walnut tree canopies, sticky panel, modified soda bottle, and Lindgren traps were deployed at different heights, with and without ethanol as an attractant and with and without walnut stem sections, or in situ limbs that had been girdled or injection with ethanol to simulate stressed tree tissues. Bark and ambrosia beetle species (Coleoptera: Curculionidae: Scolytinae) collected in greatest abundance included Ambrosiodmus rubricollis (Eichhoff), Ambrosiophilus atratus (Eichhoff), Cnestus mutilatus (Blandford), Dryoxylon onoharaense (Murayama), Euwallacea validus (Eichhoff), Monarthrum fasciatum (Say), Monarthrum mali (Fitch), Xyleborinus saxesenii (Ratzeburg), Xyleborus affinis Eichhoff, Xyleborus ferrugineus (Fabricius), Xylosandrus crassiusculus (Motschulsky), and Xylosandrus germanus (Blandford). C. mutilatus, X. saxesenii, and X. crassiusculus were more active higher in trees than most other species and were strongly attracted to ethanol via all means of lure deployment. C. mutilatus, which were captured from April through October and increased in abundance across the 3-yr study, were most abundant in late May with a second activity period in late August. © The Author 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: email@example.com.
Full Text Available As a result of the present investigations 18 species of flat bark beetles are known to occur in Atlantic Canada, 10 in New Brunswick, 17 in Nova Scotia, four on Prince Edward Island, six on insular Newfoundland, and one in Labrador. Twenty-three new provincial records are reported and nine species, Uleiota debilis (LeConte, Uleiota dubius (Fabricius, Nausibius clavicornis (Kugelann, Ahasverus advena (Waltl, Cryptolestes pusillus (Schönherr, Cryptolestes turcicus (Grouvelle, Charaphloeus convexulus (LeConte, Charaphloeus species nr. adustus, and Placonotus zimmermanni (LeConte are newly recorded in the region, one of which C. sp. nr. adustus, is newly recorded in Canada as a whole. Eight species are cosmopolitan species introduced to the region and North America, nine are native Nearctic species, and one, Pediacus fuscus Erichson, is Holarctic in distribution. All the introduced species except for one (Silvanus bidentatus (Fabricius, a saproxylic species are found on various stored products, whereas all the native species are saproxylic. Ahasverus longulus (Blatchley, is removed from the species list of New Brunswick and Charophloeus adustus (LeConte is removed from the species list of Nova Scotia. One tropical Asian species, Cryptamorpha desjardinsi (Guérin-Méneville, has been intercepted in the region in imported produce, but is not established. The substantial proportion (44% of the fauna that is comprised of introduced species is highlighted, almost all of which are synanthropic species associated with various dried stored products. The island faunas of Prince Edward Island, Cape Breton Island, and insular Newfoundland are diminished in comparison to the mainland fauna, that of Prince Edward Island being exceptionally so in comparison to other saproxylic groups found there. Of the ten native species, four can be categorized as 'apparently rare' (i.e., comprising ≤ 0.005% of specimens examined from the region. It is possibly that the
Ozcan, Gonca Ece; Cicek, Osman; Enez, Korhan; Yildiz, Mustafa
Forests form an organic unity with a great number of organic and inorganic components and tend to maintain the sustainability of their existing balance. However, some factors which adversely affect the balance of nature may interrupt this sustainability. The epidemic which is formed by bark beetles in their spreading region, due to various factors, changes the stability so much that interference is required. One of the most common methods used to monitor these beetles is pheromone-baited traps. The recognition of parameters, such as date (day/month/year), temperature and humidity, when bark beetles are captured in pheromone-baited traps, especially those used for monitoring will help to increase the trap efficiency on land and to develop an effective strategy for combating pests. In this study, an electronic control unit was added to pheromone-baited traps in order to obtain all of the above mentioned parameters. This unit operates with microcontrollers and data related to the parameters is saved in a storage unit. This is triggered by the beetle at the moment it is captured in the trap. A photovoltaic system was used to meet the energy needed for the system functioning and to complete the counting process in due time.
Grünwald, S; Pilhofer, M; Höll, W
Using fluorescence in situ hybridization (FISH) techniques and PCR-based rDNA sequencing, gut microflora in the larvae of bark- and wood-inhabiting cerambycid beetles (Rhagium inquisitor, Tetropium castaneum, Plagionotus arcuatus and Leptura rubra [Coleoptera: Cerambycidae]) was investigated. A total of 12 novel ascomycetous yeast strains were isolated from the gut content. Panfungal and strain-specific oligonucleotide probes identified two yeast strains as Candida rhagii and Candida shehatae, which were colonizing specialized organs (mycetomes) adhering to the gut of R. inquisitor and L. rubra larvae, respectively. Fragments containing these organisms were constantly being released from the mycetomes into the gut lumen. Whereas the mycetome symbiont of T. castaneum could not be identified, all larvae of this species harbored an additional bacterial endocytobiont in their gut epithelium. This novel gammaproteobacterium belonged to the Sodalis clade of insect symbionts, which includes the secondary endosymbiont of tsetse flies (Sodalis glossinidius) and the Sitophilus oryzae primary endosymbiont (SOPE). Extracellular gut flora of the investigated cerambycid larvae was comprised of Alpha-, Beta-, and Gammaproteobacteria, Actinobacteria, Firmicutes, Verrucomicrobia and Acidobacteria. However, the individual composition among investigated larvae was highly variable and supposedly depended on individual host nutrition. Copyright (c) 2009 Elsevier GmbH. All rights reserved.
Nikulina, Tatyana; Mandelshtam, Mikhail; Petrov, Alexander; Nazarenko, Vitalij; Yunakov, Nikolai
Our knowledge of Ukrainian bark and ambrosia beetles (Coleoptera: Curculionidae: Scolytinae and Platypodinae) is summarized as a baseline for future studies of the fauna, with a checklist including information on distribution, host trees, biology and taxonomy. One hundred twenty-two species are recorded from Ukraine, of which seven are recorded for the first time. One species is recorded for the first time from Europe. Previous records of 24 species are considered dubious and requiring confirmation. In contrast to the Palaearctic Catalogue (Knížek 2011b), we consider Anisandrus maiche to be first described by Kurentsov (1941) rather than by Eggers (1942); A. maiche (Eggers, 1942) is a junior synonym of A. maiche (Kurentsov, 1941).
Hicke, Jeffrey A.; Meddens, Arjan J. H.; Allen, Craig D.; Kolden, Crystal A.
Forests are major components of the carbon cycle, and disturbances are important influences of forest carbon. Our objective was to contribute to the understanding of forest carbon cycling by quantifying the amount of carbon in trees killed by two disturbance types, fires and bark beetles, in the western United States in recent decades. We combined existing spatial data sets of forest biomass, burn severity, and beetle-caused tree mortality to estimate the amount of aboveground and belowground carbon in killed trees across the region. We found that during 1984-2010, fires killed trees that contained 5-11 Tg C year-1 and during 1997-2010, beetles killed trees that contained 2-24 Tg C year-1, with more trees killed since 2000 than in earlier periods. Over their periods of record, amounts of carbon in trees killed by fires and by beetle outbreaks were similar, and together these disturbances killed trees representing 9% of the total tree carbon in western forests, a similar amount to harvesting. Fires killed more trees in lower-elevation forest types such as Douglas-fir than higher-elevation forest types, whereas bark beetle outbreaks also killed trees in higher-elevation forest types such as lodgepole pine and Engelmann spruce. Over 15% of the carbon in lodgepole pine and spruce/fir forest types was in trees killed by beetle outbreaks; other forest types had 5-10% of the carbon in killed trees. Our results document the importance of these natural disturbances in the carbon budget of the western United States.
Hicke, Jeffrey A.; Meddens, Arjan J.H.; Allen, Craig D.; Kolden, Crystal A.
Forests are major components of the carbon cycle, and disturbances are important influences of forest carbon. Our objective was to contribute to the understanding of forest carbon cycling by quantifying the amount of carbon in trees killed by two disturbance types, fires and bark beetles, in the western United States in recent decades. We combined existing spatial data sets of forest biomass, burn severity, and beetle-caused tree mortality to estimate the amount of aboveground and belowground carbon in killed trees across the region. We found that during 1984-2010, fires killed trees that contained 5-11 Tg C year-1 and during 1997-2010, beetles killed trees that contained 2-24 Tg C year-1, with more trees killed since 2000 than in earlier periods. Over their periods of record, amounts of carbon in trees killed by fires and by beetle outbreaks were similar, and together these disturbances killed trees representing 9% of the total tree carbon in western forests, a similar amount to harvesting. Fires killed more trees in lower-elevation forest types such as Douglas-fir than higher-elevation forest types, whereas bark beetle outbreaks also killed trees in higher-elevation forest types such as lodgepole pine and Engelmann spruce. Over 15% of the carbon in lodgepole pine and spruce/fir forest types was in trees killed by beetle outbreaks; other forest types had 5-10% of the carbon in killed trees. Our results document the importance of these natural disturbances in the carbon budget of the western United States.
Hicke, Jeffrey A; Meddens, Arjan J H; Kolden, Crystal A; Allen, Craig D
Forests are major components of the carbon cycle, and disturbances are important influences of forest carbon. Our objective was to contribute to the understanding of forest carbon cycling by quantifying the amount of carbon in trees killed by two disturbance types, fires and bark beetles, in the western United States in recent decades. We combined existing spatial data sets of forest biomass, burn severity, and beetle-caused tree mortality to estimate the amount of aboveground and belowground carbon in killed trees across the region. We found that during 1984–2010, fires killed trees that contained 5–11 Tg C year −1 and during 1997–2010, beetles killed trees that contained 2–24 Tg C year −1 , with more trees killed since 2000 than in earlier periods. Over their periods of record, amounts of carbon in trees killed by fires and by beetle outbreaks were similar, and together these disturbances killed trees representing 9% of the total tree carbon in western forests, a similar amount to harvesting. Fires killed more trees in lower-elevation forest types such as Douglas-fir than higher-elevation forest types, whereas bark beetle outbreaks also killed trees in higher-elevation forest types such as lodgepole pine and Engelmann spruce. Over 15% of the carbon in lodgepole pine and spruce/fir forest types was in trees killed by beetle outbreaks; other forest types had 5–10% of the carbon in killed trees. Our results document the importance of these natural disturbances in the carbon budget of the western United States. (letter)
Gretel E. Hengst; Jeffery O. Dawson
Some physical, thermal, and chemical properties of bark of eleven tree species native to the central hardwood region were measured to determine their potential to protect the vascular cambium from damage by fire. The relationship between dbh and bark thickness for each of sixteen species was determined. For purposes of monitoring seasonal trends, two species (Quercus...
Full Text Available To reduce the risk of bark- and wood-boring beetle pests, the extensive removal of logging residues is conducted in forests; however, this practice can lead to a loss of saproxylic insect diversity. Thus, finding a better pest management strategy is needed and requires additional information on the actual effects of various, differently treated logging residues for pest multiplication. In the present study, a total of 2,160 fragments of Scots pine (Pinus sylvestris L. logging residues generated during final felling in a single stand in the Drahanská Highlands in the Czech Republic were examined for bark- and wood-boring beetles. The felling occurred on four dates in 2006 (in February, May, August and November. The logging residues from each felling were left scattered on the clear-cut area or were gathered into piles. The fauna inhabiting the logging residues were investigated by peeling off the bark during the first six months of the vegetative period following the felling. The logging residues hosted species-rich assemblages of bark- and wood-boring beetles (25 species were identified. Beetle occurrence was significantly affected by felling date, logging residue type (trunk fragment or branch and branch thinner or thicker than 1 cm, diameter and the manner in which the logging residues were deposited (freely scattered, top pile layer, or bottom pile layer. The Scots pine logging residues were a substrate for the significant multiplication of several potentially significant pests (particularly, Pityogenes chalcographus [Linnaeus], Ips acuminatus [Gyllenhal] and Pityophthorus pityographus [Ratzeburg]. The results indicated that the risk of pest reproduction can be minimised by felling the trees in August (and probably also September and October. For I. acuminatus and P. pityographus, the risk can be minimised by gathering the logging residues into piles.
Zhang, Longwa; Clarke, Stephen R; Sun, Jianghua
The red turpentine beetle, Dendroctonus valens LeConte (Coleoptera: Curculionidae: Scolytinae), has caused extensive mortality of Pinus tabuliformis Carrière in north central China. The electrophysiological and behavioral activities of the four bark beetle pheromones, frontalin, exo-brevicomin, trans-verbenol, and cis-verbenol, singly or in combination with host-produced kairomones, were tested on red turpentine beetles. Both sexes showed a consistent electrophysiological response to the four test compounds. In Y-tube olfactometer bioassays, walking red turpentine beetles selected the host compound (+)-3-carene over any of the test compounds, but significantly higher numbers chose each tested pheromone over a blank control. The four compounds, tested singly or in combination, were not attractive to red turpentine beetles in field trapping studies in 2006 and 2007 and also did not significantly increase trap catch when combined with (+)-3-carene. Frontalin, alone or in combination with exo-brevicomin and trans-verbenol, significantly reduced the attractiveness of (+)-3-carene in 2006 but not in 2007. The possible roles of the pheromones in host and mate finding and selection are discussed.
Host Acceptance and Larval Competition between the Invasive Banded and European Elm Bark Beetles, Scolytus schevyrewi and S. multistriatus (Coleoptera: Scolytidae): Potential Mechanisms for Competitive Displacement
A recent survey revealed that the newly invasive banded elm bark beetle, Scolytus schevyrewi, was much more abundant than the long-established European elm bark beetle, S. multistriatus, in areas of Colorado and Wyoming, USA. This study sought to determine whether competitive displacement of S. mul...
Jose F. Negron; John B. Popp
Dryocoetes confusus Swaine, the western balsam bark beetle, is an important bark beetle associated with Abies lasiocarpa (Hook.) Nutt. (subalpine fir) in western North America. Little information is available on the life cycle and ecology of this insect in Colorado. In this study in north central Colorado, we examined its...
Jennifer G. Klutsch; Russell D. Beam; William R. Jacobi; Jose F. Negron
Due to the recent outbreaks of bark beetles in western U.S.A., research has focused on the effects of tree mortality on forest conditions, such as fuel complexes and stand structure. However, most studies have addressed outbreak populations of bark beetles only and there is a lack of information on the effect of multiple endemic, low level populations of biotic...
Kostál, V; Zahradnícková, H; Simek, P; Zelený, J
Overwintering adults of the spruce bark beetle, Ips typographus (L.) showed an unusually complex sugar/polyol cryoprotectant system. The major components of the multiple system were: glucose (177.6 mmolL(-1), March); trehalose (175.0 mmolL(-1), December); sorbitol (147.9 mmolL(-1), January); mannitol (81.2 mmolL(-1), March); and erythritol (40.7mmolL(-1), March) (in the parentheses, the maximum concentrations are shown and the month when they were reached). Other minor components were glycerol, fructose, threitol, myo-inositol, arabinitol and ribitol. Distinct seasonal patterns of accumulation/depletion in various components were found. Glycerol, trehalose and glucose started to accumulate first, during early autumn, when the air temperatures fluctuated between 20 and 0 degrees C, and diapause beetles continued in feeding. Glycerol was depleted, glucose remained stable and trehalose continued in accumulation during late autumn when the temperatures oscillated around 0 degrees C. During early winter severe frosts reaching -20 degrees C came, the beetles terminated their diapause and trehalose was partially depleted, while mannitol, sorbitol, fructose, threitol and erythritol started to accumulate. Cold weather continued also during late winter when the beetles remained quiescent. During this period, trehalose was re-accumulated, threitol and erythritol continued to increase, mannitol remained stable and sorbitol, fructose decreased. All cryoprotectans were finally cleared in the beetles which were spontaneously leaving bark during early spring. The seasonal maximum of total concentration of all cryoprotectants (578.2 mOsmol L(-1)) was reached in March. Such a concentration results in colligative depression of melting point of body fluids down by 1.08 degrees C only. It suggests that the potential cryoprotective effect of accumulated sugars and polyols was related rather to their non-colligative functions.
Robert A. Haack; Toby R. Petrice; Pascal Nzokou
Wood packing material (WPM) is an important pathway for the movement of bark- and wood-infesting insects (Haack 2006). New international standards for treating WPM, often referred to as "ISPM 15," were adopted in 2002 (FAO 2002). The two approved WPM treatments are heat treatment (56? C core temperature for 30 min) and fumigation with methyl bromide. These...
Novick, K. A.; Miniat, C. F.; Denham, S. O.; Ritger, H. M.; Williams, C.; Guldin, J. M.; Bragg, D.; Coyle, D.
Bark beetles are highly damaging pests capable of destroying large areas of southern pine forests, with significant consequences for regional timber supply and forest ecosystem carbon dynamics. A number of recent studies have shown that following bark beetle outbreak, significant effects on ecosystem carbon and water cycling can occur. Relatively few studies have explored how ecosystem carbon and water cycling interact with other factors to control the hazard or risk of bark beetle outbreaks; these interactions, and their representation in conceptual model frameworks, are the focus of this study. Pine trees defend against bark beetle attacks through the exudation of of resin - a viscous compound that deters attacking beetles through a combination of chemical and physical mechanisms. Constitutive resin flow (CRF, representing resin produced before attack) is assumed to be directly proportional to the balance between gross primary productivity (GPP) and net primary productivity (NPP) according to the Growth-Differentiation Balance theory (GDB). Thus, predictions for tree mortality and bark beetle dynamics under different management and climate regimes may be more accurate if a model framework describing the biophysical controls on resin production (e.g., GDB) were employed. Here, we synthesize measurements of resin flow, bark beetle dynamics, and ecosystem C flux from three managed loblolly pine forests in the Southeastern U.S.: the Duke Forest in Durham, NC; the Savannah River DOE site near Aiken, SC; and the Crossett Experimental Forest in southern Arkansas. We also explore the relationship between CRF and induced resin flow (IRF, representing the de novo synthesis of resin following stem wounding) in the latter two sites, where IRF was promoted by a novel tree baiting approach and prescribed fire, respectively. We assimilate observations within a hierarchical Bayesian framework to 1) test whether observations conform to the GDB hypothesis, and 2) explore effects
Wolfgang Schweigkofler; William J. Otrosina; Sheri L. Smith; Daniel R. Cluck; Kevin Maeda; Kabir G. Peay; Matteo Garbelotto
Black-stain root disease is a threat to conifer forests in western North America. The disease is caused by the ophiostomatoid fungus Leptographium wageneri (W.B. Kendr.) M.J. Wingf., which is associated with a number of bark beetle (Coleoptera: Scolytidae) and weevil species (Coleoptera: Curculionidae). We developed a polymerase chain reaction test...
Full Text Available The subject of the present research is the water storage capacity of bark of seven forest tree species: Pinus sylvestris L., Larix decidua Mill., Abies alba Mill., Pinus sylvestris L., Quercus robur L., Betula pendula Ehrh. and Fagus sylvatica L. The aim of the research is to demonstrate differences in the formation of bark water storage capacity between species and to identify factors influencing the hydrological properties of bark. The maximum water storage capacity of bark was determined under laboratory conditions by performing a series of experiments simulating rainfall and by immersing bark samples in containers filled with water. After each single experiment, the bark samples were subjected to gravity filtration in a desiccator partially filled with water. The experiments lasted from 1084 to 1389 hours, depending on the bark sample. In all the studied species, bark sampled from the thinnest trees is characterized by the highest water storage capacity expressed in mm H2O · cm-3, while bark sampled from the thickest trees - by the lowest capacity. On the other hand, bark sampled from the thickest trees is characterized by the highest water storage capacity expressed in H2O · cm-2 whereas bark from the thinnest trees - by the lowest capacity. In most species tested, as the tree thickness and thus the bark thickness and the coefficient of development of the interception surface of bark increase, the sorption properties of the bark decrease with bark depth, and the main role in water retention is played by the outer bark surface. The bark of European beech is an exception because of the smallest degree of surface development and because the dominant process is the absorption of water. When examining the hydrological properties of bark and calculating its parameters, one needs to take into account the actual surface of the bark of trees. Disregarding the actual bark surface may lead to significant errors in the interpretation of research
Full Text Available Bark beetles cause widespread damages in the coniferous-dominated forests of central Europe and North America. In the future, areas affected by bark beetles may further increase due to climate change. However, the early detection of the bark beetle green attack can guide management decisions to prevent larger damages. For this reason, a field-based bark beetle monitoring program is currently implemented in Germany. The combination of remote sensing and field data may help minimizing the reaction time and reducing costs of monitoring programs covering large forested areas. In this case study, RapidEye and TerraSAR-X data were analyzed separately and in combination to detect bark beetle green attack. The remote sensing data were acquired in May 2009 for a study site in south-west Germany. In order to distinguish healthy areas and areas affected by bark beetle green attack, three statistical approaches were compared: generalized linear models (GLM, maximum entropy (ME and random forest (RF. The spatial scale (minimum mapping unit was 78.5 m2. TerraSAR-X data resulted in fair classification accuracy with a cross-validated Cohen’s Kappa Coefficient (kappa of 0.23. RapidEye data resulted in moderate classification accuracy with a kappa of 0.51. The highest classification accuracy was obtained by combining the TerraSAR-X and RapidEye data, resulting in a kappa of 0.74. The accuracy of ME models was considerably higher than the accuracy of GLM and RF models.
Youngblood, Andrew; Grace, James B; McIver, James D
Many low-elevation dry forests of the western United States contain more small trees and fewer large trees, more down woody debris, and less diverse and vigorous understory plant communities compared to conditions under historical fire regimes. These altered structural conditions may contribute to increased probability of unnaturally severe wildfires, susceptibility to uncharacteristic insect outbreaks, and drought-related mortality. Broad-scale fuel reduction and restoration treatments are proposed to promote stand development on trajectories toward more sustainable structures. Little research to date, however, has quantified the effects of these treatments on the ecosystem, especially delayed and latent tree mortality resulting directly or indirectly from treatments. In this paper, we explore complex hypotheses relating to the cascade of effects that influence ponderosa pine (Pinus ponderosa) and Douglas-fir (Pseudotsuga menziesii) mortality using structural equation modeling (SEM). We used annual census and plot data through six growing seasons after thinning and four growing seasons after burning from a replicated, operational-scale, completely randomized experiment conducted in northeastern Oregon, USA, as part of the national Fire and Fire Surrogate study. Treatments included thin, burn, thin followed by burn (thin + burn), and control. Burn and thin + burn treatments increased the proportion of dead trees while the proportion of dead trees declined or remained constant in thin and control units, although the density of dead trees was essentially unchanged with treatment. Most of the new mortality (96%) occurred within two years of treatment and was attributed to bark beetles. Bark beetle-caused tree mortality, while low overall, was greatest in thin + burn treatments. SEM results indicate that the probability of mortality of large-diameter ponderosa pine from bark beetles and wood borers was directly related to surface fire severity and bole charring, which
Reed, David E.; Ewers, Brent E.; Pendall, Elise; Frank, John; Kelly, Robert
Insect outbreaks are major disturbances that affect a land area similar to that of forest fires across North America. The recent mountain pine bark beetle ( D endroctonus ponderosae) outbreak and its associated blue stain fungi ( Grosmannia clavigera) are impacting water partitioning processes of forests in the Rocky Mountain region as the spatially heterogeneous disturbance spreads across the landscape. Water cycling may dramatically change due to increasing spatial heterogeneity from uneven mortality. Water and energy storage within trees and soils may also decrease, due to hydraulic failure and mortality caused by blue stain fungi followed by shifts in the water budget. This forest disturbance was unique in comparison to fire or timber harvesting because water fluxes were altered before significant structural change occurred to the canopy. We investigated the impacts of bark beetles on lodgepole pine ( Pinus contorta) stand and ecosystem level hydrologic processes and the resulting vertical and horizontal spatial variability in energy storage. Bark beetle-impacted stands had on average 57 % higher soil moisture, 1.5 °C higher soil temperature, and 0.8 °C higher tree bole temperature over four growing seasons compared to unimpacted stands. Seasonal latent heat flux was highly correlated with soil moisture. Thus, high mortality levels led to an increase in ecosystem level Bowen ratio as sensible heat fluxes increased yearly and latent heat fluxes varied with soil moisture levels. Decline in canopy biomass (leaf, stem, and branch) was not seen, but ground-to-atmosphere longwave radiation flux increased, as the ground surface was a larger component of the longwave radiation. Variability in soil, latent, and sensible heat flux and radiation measurements increased during the disturbance. Accounting for stand level variability in water and energy fluxes will provide a method to quantify potential drivers of ecosystem processes and services as well as lead to greater
Full Text Available This study was aimed to investigate the response of bark beetle community structure to green-tree retention in a Korean pine tree forest between 2013 and 2015. Five types of retention methods were evaluated to investigate the retention effect on insect community structure at various sites in Keunjeogol, Samcheok, and Gangwon-do. Lindgren funnel traps were installed to collect insects from July to August, over a 3-year period. Overall, 690 individuals and 29 species of Scolytinae were collected, with populations of insects appearing to gradually increase by each year of the study. Results of the insect community analysis showed that most survey sites presented a higher diversity than the control site annually except in 2015. This study can be used as a baseline dataset for the long-term study of early changes in insect community in response to green-tree retention in forests.
Baier, P.; Pennerstorfer, J.; Schopf, A.
The provision of drinking water of high quality is a precious service of forests. Large-scale disturbances like forest fires, wind throws, pest outbreaks and subsequent clear cutting may lead to changes in hydrology (runoff as well as percolation). Furthermore, water quality can be negatively influenced by increased erosion, increased decomposition of litter and humus and leaching of nitrate. Large-scale epidemics of forest pests may induce forest decline at landscape scale with subsequent long-lasting negative effects on water quality. The European spruce bark beetle, Ips typographus (L.), is one of the most significant sources of mortality in mature spruce forest ecosystems in Eurasia. The objective of this study was to apply a complex predisposition assessment system for hazard rating and for the evaluation of climate change impacts for the water protection forests of the City of Vienna in Wildalpen. The following steps have been done to adapt/apply the bark beetle phenology model and the hazard rating system: -application, adaptation and validation of the bark beetle phenology model PHENIPS concerning start of dispersion, brood initiation, duration of development, beginning of sister broods, voltinism and hibernation - spatial/temporal modelling of the phenology and voltinism of I. typographus using past, present as well as projected climate data - application and validation of the stand- and site related long-term predisposition assessment system using forest stand/site data, annual damage reports and outputs of phenology modelling as data input - mapping of endangered areas and assessment of future susceptibility to infestations by I. typographus and other disturbing agents based on climate scenarios using GIS. The assessment of site- and stand-related predisposition revealed that the forest stands in Wildalpen are highly susceptible to bark beetle infestation. More than 65% of the stands were assigned to the predisposition classes high/very high. Only 10% of
Meddens, Arjan J. H.
Recently, insect outbreaks across North America have dramatically increased and the forest area affected by bark beetles is similar to that affected by fire. Remote sensing offers the potential to detect insect outbreaks with high accuracy. Chapter one involved detection of insect-caused tree mortality on the tree level for a 90km2 area in northcentral Colorado. Classes of interest included green trees, multiple stages of post-insect attack tree mortality including dead trees with red needles ("red-attack") and dead trees without needles ("gray-attack"), and non-forest. The results illustrated that classification of an image with a spatial resolution similar to the area of a tree crown outperformed that from finer and coarser resolution imagery for mapping tree mortality and non-forest classes. I also demonstrated that multispectral imagery could be used to separate multiple postoutbreak attack stages (i.e., red-attack and gray-attack) from other classes in the image. In Chapter 2, I compared and improved methods for detecting bark beetle-caused tree mortality using medium-resolution satellite data. I found that overall classification accuracy was similar between single-date and multi-date classification methods. I developed regression models to predict percent red attack within a 30-m grid cell and these models explained >75% of the variance using three Landsat spectral explanatory variables. Results of the final product showed that approximately 24% of the forest within the Landsat scene was comprised of tree mortality caused by bark beetles. In Chapter 3, I developed a gridded data set with 1-km2 resolution using aerial survey data and improved estimates of tree mortality across the western US and British Columbia. In the US, I also produced an upper estimate by forcing the mortality area to match that from high-resolution imagery in Idaho, Colorado, and New Mexico. Cumulative mortality area from all bark beetles was 5.46 Mha in British Columbia in 2001-2010 and
Jakuš, R.; Edwards-Jonášová, Magda; Cudlín, Pavel; Blaženec, M.; Ježík, M.; Havlíček, František; Moravec, Ivo
Roč. 25, č. 6 (2011), s. 965-973 ISSN 0931-1890 R&D Projects: GA MŠk 2B06068; GA MŠk(CZ) ED1.1.00/02.0073 Institutional research plan: CEZ:AV0Z60870520 Keywords : Keywords Norway spruce * Ips typographus * Host selection * Bark beetle attack * Crown geometry Subject RIV: GK - Forestry Impact factor: 1.685, year: 2011 http://www.springerlink.com/content/p476l65x8hx72634/
Ewers, B. E.; Pendall, E.; Norton, U.; Millar, D.; Mackay, D. S.; Frank, J. M.; Massman, W. J.; Hyde, K.
Bark beetles increased conifer tree mortality across western North America due to past land use interacting with climate change. For both mountain pine and spruce beetles, the mechanism of mortality is hydraulic failure due to xylem occlusion by beetle-carried blue stain fungi, which causes the trees to die from symptoms that are the same as extreme drought. As the mortality event peaked in the last decade, the hypothesized effects on forest biogeochemical processes were 1) lower forest water use from xylem occlusion, 2) less carbon uptake from limited canopy gas exchange, 3) increased nitrogen cycling from increased litterfall and soil moisture and 4) increased streamflow and organic N and C loading at the watershed scale from the first three consequences. The stand-scale effects during mortality were as predicted with transpiration falling by 10-35% in proportion to the occluded xylem, carbon uptake declining by > 50% due to lack of canopy gas exchange and nitrogen cycling increasing from elevated litter inputs and stimulated organic matter decomposition. Some stands, especially mid-elevation lodgepole pine, did not follow these trends because of residual vegetation taking advantage of the increased resources from the dead trees and rapid succession within 5 years of new grasses, shrubs and tree seedlings as well as increased resource use by surviving canopy trees. In a high elevation spruce stand, the lower water use lasted for only three years while summer carbon uptake was only significantly reduced for a year. At the scale of small to medium-sized watersheds, the impact of mortality was not detectable in stream flow due to the spatial and temporal scale muting of the mortality signal as temporal and spatial scales increase. Current ecosystem and watershed models miss these compensating mechanisms with increasing scale and thus over predict the impact of bark beetle mortality.
Hovorka, Oldřich; Kindl, Jiří; Kalinová, Blanka; Knížek, M.; Vrkočová, Pavlína; Koutek, Bohumír
Roč. 129, č. 4 (2005), 221-226 ISSN 0931-2048 R&D Projects: GA ČR(CZ) GA203/97/0037; GA MZe(CZ) QD0332 Institutional research plan: CEZ:AV0Z4055905 Keywords : bark beetles * host colonization * pheromones Subject RIV: CC - Organic Chemistry Impact factor: 0.703, year: 2005
Menkis, A; Lynikienė, J; Marčiulynas, A; Gedminas, A; Povilaitienė, A
We studied the occurrence, morphology and phenology of Dendroctonus micans in Lithuania and the fungi associated with the beetle at different developmental stages. The occurrence of D. micans was assessed in 19 seed orchards (at least 40 years old) of Picea abies (L. Karst.) situated in different parts of the country. Bark beetle phenology was studied in two sites: a seed orchard of P. abies and a plantation of Picea pungens (Engelm.). D. micans morphology was assessed under the dissection microscope using individuals at different developmental stages that were sampled during phenology observations. Communities of fungi associated with D. micans were studied using both fungal culturing methods and direct high-throughput sequencing from D. micans. Results showed that the incidence D. micans was relatively rare and D. micans was mainly detected in central and eastern Lithuania. The life cycle included the following stages: adult, egg, I-V developmental stage larvae and pupa. However, development of D. micans was quicker and its nests larger under the bark of P. pungens than of P. abies, indicating the effect of the host species. Fungal culturing and direct high-throughput sequencing revealed that D. micans associated fungi communities were species rich and dominated by yeasts from a class Saccharomycetes. In total, 319 fungal taxa were sequenced, among which Peterozyma toletana (37.5% of all fungal sequences), Yamadazyma scolyti (30.0%) and Kuraishia capsulate (17.7%) were the most common. Plant pathogens and blue stain fungi were also detected suggesting their potentially negative effects to both tree health and timber quality.
King, A.; Ewers, B. E.; Sivanpillai, R.; Pendall, E.
Bark beetles have caused widespread regional mortality in both lodgepole and Engelmann spruce forests across western North America, and while studies have addressed the impact on water partitioning caused by the mountain pine beetle, spruce beetle which often occur at high elevations with larger snowpack might have a disproportional impact. Beetle caused mortality can have significant effects on the hydrology of a watershed and therefore needs to be considered when evaluating increased runoff. The objective of this project was to generate maps showing beetle caused mortality for lodgepole pine and spruce fir forests that capture changes to the landscape to improve hydrologic models. Our study area in southeast Wyoming covered an area of approximately 2 by 4 km from 2700 to 2800m elevation range. High spatial resolution (0.5m) aerial imagery acquired by the Airborne Environmental Research Observational Camera (AEROCam) in fall 2011, provided by the Upper Midwest Aerospace Consortium (UMAC), was manually classified into four conifer thematic classes: live and dead lodgepole pine, and live and dead spruce/fir. The classified high resolution image was then verified by tree surveys conducted July-September, 2012 documenting species, tree diameter at breast height (dbh), and the stage of beetle infestation for each tree. After verification the high resolution aerial images were used to train and evaluate the accuracy of a supervised classification of a Landsat 5 Thematic Mapper image from the same time period and area. The preliminary results of a supervised classification show that map accuracy was 57%, 77%, 44%, and 83% for lodgepole live and dead, and spruce/fir live and dead respectively. The highest commission error, 24%, was for dead lodgepole pine being falsely labeled dead spruce/fir. The second highest commission error, 22%, was for live spruce/fir falsely labeled dead spruce/fir. The results indicate high spectral overlap between dead spruce/fir and dead
Zuo, Juan; Cornelissen, Johannes H. C.; Hefting, Mariet M.; Sass-Klaassen, Ute; van Logtestijn, Richard S. P.; van Hal, Jurgen; Goudzwaard, Leo; Liu, Jin C.; Berg, Matty P.
Facilitation between species is thought to be a key mechanism in community assembly and diversity, as certain species create microhabitats for others. A profound characteristic of forest ecosystems is a large amount of dead wood which is colofiised by a vast array of invertebrate species. Bark
Zuo, J.; Cornelissen, J.H.C.; Hefting, M.M.; Sass-Klaassen, U.; van Logtestijn, R.S.P; van Hal, J.R.; Goudzwaard, L.; Liu, J.C.; Berg, M.P.
Facilitation between species is thought to be a key mechanism in community assembly and diversity, as certain species create microhabitats for others. A profound characteristic of forest ecosystems is a large amount of dead wood which is colonised by a vast array of invertebrate species. Bark
Vanderhoof, M. K.; Williams, C. A.
Changes in canopy cover due to disturbance-related mortality have been shown to profoundly impact parameters within the surface energy balance and water budget. A shift in such fluxes can have consequences for surface temperature, cloudiness, run-off and stream flow, forest regeneration and net primary productivity. Current outbreaks of native bark beetles in western North America are some of the largest and most severe in recorded history. In recent outbreaks, bark beetles have reduced the basal area of host-dominated forests by up to 70%; with over-story mortality often exceeding 90% in mature, even-aged stands. The magnitude, frequency and intensity of recent outbreaks have been attributed to warmer summer and winter temperatures and drought conditions as a result of climate change. However, despite the likelihood that canopy mortality from bark beetle attacks will have profound effects on forest albedo and evapotranspiration, consequences for this disturbance type remain largely un-documented. This study addressed the question: how does a bark beetle outbreak event influence surface albedo and evapotranspiration? Seasonal patterns of surface temperature, albedo, evapotranspiration, and radiative forcing were modeled for lodgepole and ponderosa pine stands by outbreak age using Moderate Resolution Imaging Spectroradiometer (MODIS) data within the south-central Rocky Mountains. Beetle damage data was derived from both field-based plots as well as aerial surveys. The prevalence of bark beetle outbreaks in high-elevation environments, which are exceedingly sensitive to climate change, necessitates the importance of understanding the energy and evapotranspiration consequences of such events.
Sarah J Hart
Full Text Available Understanding disturbance interactions and their ecological consequences remains a major challenge for research on the response of forests to a changing climate. When, where, and how one disturbance may alter the severity, extent, or occurrence probability of a subsequent disturbance is encapsulated by the concept of linked disturbances. Here, we evaluated 1 how climate and forest habitat variables, including disturbance history, interact to drive 2000s spruce beetle (Dendroctonus rufipennis infestation of Engelmann spruce (Picea engelmannii across the Southern Rocky Mountains; and 2 how previous spruce beetle infestation affects subsequent infestation across the Flat Tops Wilderness in northwestern Colorado, which experienced a severe landscape-scale spruce beetle infestation in the 1940s. We hypothesized that drought and warm temperatures would promote infestation, whereas small diameter and non-host trees, which may reflect past disturbance by spruce beetles, would inhibit infestation. Across the Southern Rocky Mountains, we found that climate and forest structure interacted to drive the 2000s infestation. Within the Flat Tops study area we found that stands infested in the 1940s were composed of higher proportions of small diameter and non-host trees ca. 60 years later. In this area, the 2000s infestation was constrained by a paucity of large diameter host trees (> 23 cm at diameter breast height, not climate. This suggests that there has not been sufficient time for trees to grow large enough to become susceptible to infestation. Concordantly, we found no overlap between areas affected by the 1940s infestation and the current infestation. These results show a severe spruce beetle infestation, which results in the depletion of susceptible hosts, can create a landscape template reducing the potential for future infestations.
Mayer, François; Piel, Frédéric B; Cassel-Lundhagen, Anna; Kirichenko, Natalia; Grumiau, Laurent; Økland, Bjørn; Bertheau, Coralie; Grégoire, Jean-Claude; Mardulyn, Patrick
While phylogeographic patterns of organisms are often interpreted through past environmental disturbances, mediated by climate changes, and geographic barriers, they may also be strongly influenced by species-specific traits. To investigate the impact of such traits, we focused on two Eurasian spruce bark beetles that share a similar geographic distribution, but differ in their ecology and reproduction. Ips typographus is an aggressive tree-killing species characterized by strong dispersal, whereas Dendroctonus micans is a discrete inbreeding species (sib mating is the rule), parasite of living trees and a poor disperser. We compared genetic variation between the two species over both beetles' entire range in Eurasia with five independent gene fragments, to evaluate whether their intrinsic differences could have an influence over their phylogeographic patterns. We highlighted widely divergent patterns of genetic variation for the two species and argue that the difference is indeed largely compatible with their contrasting dispersal strategies and modes of reproduction. In addition, genetic structure in I. typographus divides European populations in a northern and a southern group, as was previously observed for its host plant, and suggests past allopatric divergence. A long divergence time was estimated between East Asian and other populations of both species, indicating their long-standing presence in Eurasia, prior to the last glacial maximum. Finally, the strong population structure observed in D. micans for the mitochondrial locus provides insights into the recent colonization history of this species, from its native European range to regions where it was recently introduced. © 2015 John Wiley & Sons Ltd.
Yaman, Mustafa; Radek, Renate
A new neogregarine pathogen of the great spruce bark beetle, Dendroctonus micans (Coleoptera: Curculionidae, Scolytinae), is described based on light microscopy and ultrastructural characteristics. The pathogen infects the fat body and the hemolymph of the beetle. The infection was nonsynchronous so that different developmental stages could be observed simultaneously in the hemolymph. All life stages from sporozoite to oocyst of the pathogen including micronuclear and macronuclear merozoites were detected. The sporozoites measured about 8.7 × 1.9 μm and trophozoites, 11.9 × 3.3 μm. Micronuclear merozoites seen in the hemolymph were motile, elongate, slightly broader at the anterior pole, and measured 18.4 × 2.0 μm. Macronuclear merozoites had a size of ca. 16.4 × 2.3 μm. Gametogamy results in the formation of two paired oocysts within a gametocyst. The lemon-shaped oocyst measured 10.9 × 6.1 μm and had a very thick wall (375-450 nm). All morphological and ultrastructural characteristics of the life cycle stages indicate that the described neogregarine in D. micans is clearly different from known Mattesia species infecting bark beetles, and from any other described Mattesia spp. Therefore, we create a new species, Mattesia weiseri sp. nov.
Netherer, Sigrid; Matthews, Bradley; Katzensteiner, Klaus; Blackwell, Emma; Henschke, Patrick; Hietz, Peter; Pennerstorfer, Josef; Rosner, Sabine; Kikuta, Silvia; Schume, Helmut; Schopf, Axel
Drought is considered to enhance susceptibility of Norway spruce (Picea abies) to infestations by the Eurasian spruce bark beetle (Ips typographus, Coleoptera: Curculionidae), although empirical evidence is scarce. We studied the impact of experimentally induced drought on tree water status and constitutive resin flow, and how physiological stress affects host acceptance and resistance. We established rain-out shelters to induce both severe (two full-cover plots) and moderate (two semi-cover plots) drought stress. In total, 18 sample trees, which were divided equally between the above treatment plots and two control plots, were investigated. Infestation was controlled experimentally using a novel ‘attack box’ method. Treatments influenced the ratios of successful and defended attacks, but predisposition of trees to infestation appeared to be mainly driven by variations in stress status of the individual trees over time. With increasingly negative twig water potentials and decreasing resin exudation, the defence capability of the spruce trees decreased. We provide empirical evidence that water-limiting conditions impair Norway spruce resistance to bark beetle attack. Yet, at the same time our data point to reduced host acceptance byI. typographus with more extreme drought stress, indicated by strongly negative pre-dawn twig water potentials. PMID:25417785
Steven Seybold; Richard Penrose; Andrew Graves
This chapter discusses the native ranges, histories of introduction, recent research efforts, and the potential impacts of some of 22 species of invasive scolytids in Californiaâs Mediterranean forest ecosystems. The diversity of native and ornamental tree species, the varied climatic zones, and the widespread importation of nursery stock and packaged cargo have made...
Ewers, B. E.; Norton, U.; Borkhuu, B.; Reed, D. E.; Peckham, S. D.; Biederman, J. A.; King, A.; Gochis, D. J.; Brooks, P. D.; Harpold, A. A.; Frank, J. M.; Massman, W. J.; Mackay, D. S.; Pendall, E. G.
The recent epidemic of bark beetles across western North America has impacted conifers from low to high elevations from New Mexico to Yukon. The mechanism of mortality is clear, with both mountain pine and spruce beetles killing trees by introducing xylem occluding blue stain fungi which dramatically stops transpiration. The visual impact of this outbreak is stunning, with mortality of canopy trees over 90% in some stands. However, emerging work shows that the impact on ecosystem processes is not as dramatic. We hypothesize that increased soil water and nitrogen sets up rapid succession of plant communities, which quickly restores ecosystem processing of water, carbon and nitrogen, while spatial patchiness of mortality and belowground responses mutes the impact as spatial scale increases from stands to watersheds. In support of our hypothesis we found 1) Soil nitrogen and moisture increase within one growing season but decrease to the same as uninfested stands five years later. 2) Soil respiration is correlated with live tree basal area suggesting a large component of autotrophic respiration. 3) Once stands have more than 50% basal area mortality, seedling density increases up to five fold and total non-tree understory cover increased two fold both within five years after infestation. 4) Ecosystem scale estimates of water vapor fluxes do not decline as rapidly as overstory leaf area. 5) Stable isotopes of snow, soil and stream water suggest that increased below canopy evapotranspiration nearly compensates for reduced canopy transpiration. 6) Nested watershed data shows that precipitation variations are much more important in regulating streamflow than changes in canopies from bark beetle induced mortality. These results were tested in the Terrestrial Regional Ecosystem Exchange Simulator (TREES) model. TREES was able to predict annual changes in the carbon fluxes but had difficulty simulating soil moisture and annual water budgets likely due to inadequate abiotic
Daniel R. Miller; Robert J. Rabaglia; Christopher M. Crowe
Our objective was to verify the need for separate traps baited with ethanol or ethanol and ()-α-pinene for bark and ambrosia beetles in pine stands of the southeastern U.S. Eight trapping experiments were conducted in stands of mature pine in Alabama, Florida, Georgia, North Carolina, and South Carolina.
Haidler, B.; Wegensteiner, R.; Weiser, Jaroslav
Roč. 26, č. 1 (2003), s. 257-260 ISSN 1027-3115. [European Meeting "Entomopathogens and Insect Parasitic Nematodes /8./. Atheny, 29.05.2001-02.06.2001] Institutional research plan: CEZ:AV0Z5007907 Keywords : spruce bark beetles * Scolitidae Subject RIV: GF - Plant Pathology, Vermin, Weed, Plant Protection
Previous studies have provided evidence that monoterpene odors from healthy host Scotch pine (Pinus sylvestris) and non-host Norway spruce (Picea abies) significantly reduce the attraction of flying bark beetles, Pityogenes bidentatus, to their aggregation pheromone components (grandisol and cis-ver...
C.J. Fettig; R.R. Borys; C.P. and Dabney
We examined bark beetle responses to fire and fire surrogate treatments 2 and 4 years after the application of prescribed fire in a mixed-conifer forest in northern California. Treatments included an untreated control (C), thinning from below (T), and applications of prescribed fire (B) and T + B replicated three times in 10-ha experimental units. A total of 1,822...
Thorsten Zeppenfeld; Miroslav Svoboda; R. Justin DeRose; Marco Heurich; Jorg Muller; Pavla Cizkova; Martin Stary; Radek Bace; Daniel C. Donato
Large, severe disturbances drive many forest ecosystems over the long term, but pose management uncertainties when human experience with them is limited. Recent continent-scale outbreaks of bark beetles across the temperate Northern Hemisphere have raised major concerns as to whether coniferous forests will regenerate back towards pre-outbreak condition and...
Jonášová, Magda; Prach, Karel
Roč. 141, č. 6 (2008), s. 1525-1535 ISSN 0006-3207 R&D Projects: GA AV ČR KJB600870701 Institutional research plan: CEZ:AV0Z60870520; CEZ:AV0Z60050516 Keywords : bark beetle * salvage logging * understory vegetation * mountain spruce forests, disturbance Subject RIV: EF - Botanics Impact factor: 3.566, year: 2008
Su, Ye; Langhammer, Jakub; Jarsjö, Jerker
Under the present conditions of climate warming, there has been an increased frequency of bark beetle-induced tree mortality in Asia, Europe, and North America. This study analyzed seven years of high frequency monitoring of in-stream electrical conductivity (EC), hydro-climatic conditions, and vegetation dynamics in four experimental catchments located in headwaters of the Sumava Mountains, Central Europe. The aim was to determine the effects of insect-induced forest disturbance on in-stream EC at multiple timescales, including annual and seasonal average conditions, daily variability, and responses to individual rainfall events. Results showed increased annual average in-stream EC values in the bark beetle-infected catchments, with particularly elevated EC values during baseflow conditions. This is likely caused by the cumulative loading of soil water and groundwater that discharge excess amounts of substances such as nitrogen and carbon, which are released via the decomposition of the needles, branches, and trunks of dead trees, into streams. Furthermore, we concluded that infestation-induced changes in event-scale dynamics may be largely responsible for the observed shifts in annual average conditions. For example, systematic EC differences between baseflow conditions and event flow conditions in relatively undisturbed catchments were essentially eliminated in catchments that were highly disturbed by bark beetles. These changes developed relatively rapidly after infestation and have long-lasting (decadal-scale) effects, implying that cumulative impacts of increasingly frequent bark beetle outbreaks may contribute to alterations of the hydrogeochemical conditions in more vulnerable mountain regions.
Eric M. Pfeifer; Jeffrey A. Hicke; Arjan J.H. Meddens
Bark beetle epidemics result in tree mortality across millions of hectares in North America. However, few studies have quantified impacts on carbon (C) cycling. In this study, we quantified the immediate response and subsequent trajectories of stand-level aboveground tree C stocks and fluxes using field measurements and modeling for a location in central Idaho, USA...
Rodman R. Linn; Carolyn H. Sieg; Chad M. Hoffman; Judith L. Winterkamp; Joel D. McMillin
We used a physics-based model, HIGRAD/FIRETEC, to explore changes in within-stand wind behavior and fire propagation associated with three time periods in pinyon-juniper woodlands following a drought-induced bark beetle outbreak and subsequent tree mortality. Pinyon-juniper woodland fuel complexes are highly heterogeneous. Trees often are clumped, with sparse patches...
Kopáček, Jiří; Cudlín, Pavel; Fluksová, H.; Kaňa, Jiří; Picek, T.; Šantrůčková, H.; Svoboda, M.; Vaněk, D.
Roč. 20, č. 3 (2015), s. 305-323 ISSN 1239-6095 R&D Projects: GA ČR(CZ) GAP504/12/1218 Institutional support: RVO:60077344 ; RVO:67179843 Keywords : bark beetle * litter * Norway spruce Subject RIV: EH - Ecology, Behaviour Impact factor: 1.476, year: 2015
Coffee berry borer(CBB), Hypothenemus hampei, is a serious pest of coffee worldwide and a new invasive pest in Hawaii. Adult flat bark beetles, mainly Leptophloeus sp.(75%) and Cathartus quadricollis(21%) (Coleoptera: Laemophloeidae and Silvanidae, respectively), were found feeding in CBB-infested c...
Zýval, V.; Křenová, Zdeňka; Kindlmann, Pavel
Roč. 204, part B (2016), s. 394-402 ISSN 0006-3207 R&D Projects: GA MŠk(CZ) LO1415 Institutional support: RVO:67179843 Keywords : Natura 2000 * Forest ecosystem management * Natural disturbances * Bark beetles * National park conservation policy Subject RIV: EH - Ecology, Behaviour Impact factor: 4.022, year: 2016
Biederman, Joel A.; Meixner, Thomas; Harpold, Adrian A.; Reed, David E.; Gutmann, Ethan D.; Gaun, Janelle A.; Brooks, Paul D.
A North American bark beetle infestation has killed billions of trees, increasing soil nitrogen and raising concern for N loss impacts on downstream ecosystems and water resources. There is surprisingly little evidence of stream N response in large basins, which may result from surviving vegetation uptake, gaseous loss, or dilution by streamflow from unimpacted stands. Observations are lacking along hydrologic flow paths connecting soils with streams, challenging our ability to determine where and how attenuation occurs. Here we quantified biogeochemical concentrations and fluxes at a lodgepole pine-dominated site where bark beetle infestation killed 50-60% of trees. We used nested observations along hydrologic flow paths connecting hillslope soils to streams of up to third order. We found soil water NO3 concentrations increased 100-fold compared to prior research at this and nearby southeast Wyoming sites. Nitrogen was lost below the major rooting zone to hillslope groundwater, where dissolved organic nitrogen (DON) increased by 3-10 times (mean 1.65 mg L-1) and NO3-N increased more than 100-fold (3.68 mg L-1) compared to preinfestation concentrations. Most of this N was removed as hillslope groundwater drained through riparian soils, and NO3 remained low in streams. DON entering the stream decreased 50% within 5 km downstream, to concentrations typical of unimpacted subalpine streams (~0.3 mg L-1). Although beetle outbreak caused hillslope N losses similar to other disturbances, up to 5.5 kg ha-1y-1, riparian and in-stream removal limited headwater catchment export to <1 kg ha-1y-1. These observations suggest riparian removal was the dominant mechanism preventing hillslope N loss from impacting streams.
Stevenson, Philip C; Green, Paul W C; Veitch, Nigel C; Farrell, Iain W; Kusolwa, Paul; Belmain, Steven R
Zanha africana (Radlk.) Exell (Sapindaceae) root bark is used by farmers throughout sub-Saharan Africa to protect stored grain from bruchid beetles, such as Callosobruchus maculatus. Chloroform, methanol and water extracts of Z. africana root bark inhibited oviposition and caused significantly higher mortality of C. maculatus at a rate of application equivalent to that applied by farmers compared to control insects. The chloroform extract contained nor-hopanes rarely found in plants of which seven were isolated, one of which was previously known. Two of the most abundant nor-hopanes 3β,6β-dihydroxy-7β-[(4-hydroxybenzoyl)oxy]-21αH-24-norhopa-4(23),22(29)-diene and 3β,6β-dihydroxy-7β-[(4-hydroxybenzoyl)oxy]-24-norhopa-4(23),17(21)-diene were toxic to and reduced oviposition of C. maculatus in a dose dependent manner. Z. africana root bark is rich in insecticidal compounds that account for its effective use by smallholder farmers as an alternative to conventional insecticides. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.
Aukema, Brian H.; Zhu, Jun; Møller, Jesper
. This interaction results in an expanding forest gap, with subsequent colonization by early-successional vegetation. Spatial position strongly affects the likelihood of tree mortality. A red pine is initially very likely to avoid attack by tree-killing Ips beetles, but attack becomes increasingly likely......, in that the proportion of killed trees that were not first colonized by root organisms increases. This positive feedback is very weak, however, and we propose the slope between beetle population density and reliance on host stress as a quantitative distinction along a gradient from noneruptive through eruptive species....... Almost all trees colonized by Ips were subsequently colonized by wood borers, likely a source of negative feedback. We discuss implications to our overall understanding of cross-scale interactions, between-guild interactions, forest declines, and eruptive thresholds....
Contributions by Host Trees and Insect Activity to Bacterial Communities in Dendroctonus valens (Coleoptera: Curculionidae) Galleries, and Their High Overlap With Other Microbial Assemblages of Bark Beetles.
Mason, Charles J; Hanshew, Alissa S; Raffa, Kenneth F
Bark beetles are associated with a diversity of symbiotic microbiota that can mediate interactions with their host plants. Dendroctonus valens LeConte is a widely distributed bark beetle in North and Central America, and initiates solitary attacks on several species of Pinus in the Great Lakes region. In this study, we aimed to further characterize the bacterial community associated with D. valens feeding galleries using next-generation sequencing, and the possible contributions of both tree-resident and insect-associated bacteria to these consortia. We found that D. valens galleries harbor a diversity of microbial associates. Many of these associates were classified into a few taxonomic groups, of which Gammaproteobacteria were the most abundant class. Of the Gammaproteobacteria detected, many formed clades with 16S-rRNA sequences of bacteria previously associated with D. valens Many of the bacteria sequences detected in the galleries were similar to bacteria that function in detoxification, kairomone metabolism, and nitrogen fixation and cycling. The abundance of bacteria in galleries were 7× and 44× higher than in the surrounding uninfested tissues, and that were not attacked by D. valens, respectively. This suggests that the bacteria present in beetle galleries are largely introduced by D. valens and proliferate in this environment. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: firstname.lastname@example.org.
A. R. Berg
Full Text Available Over the last decade, extensive beetle outbreaks in western North America have destroyed over 100 000 km2 of forest throughout British Columbia and the western United States. Beetle infestations impact monoterpene emissions through both decreased emissions as trees are killed (mortality effect and increased emissions in trees under attack (attack effect. We use 14 yr of beetle-induced tree mortality data together with beetle-induced monoterpene emission data in the National Center for Atmospheric Research (NCAR Community Earth System Model (CESM to investigate the impact of beetle-induced tree mortality and attack on monoterpene emissions and secondary organic aerosol (SOA formation in western North America. Regionally, beetle infestations may have a significant impact on monoterpene emissions and SOA concentrations, with up to a 4-fold increase in monoterpene emissions and up to a 40% increase in SOA concentrations in some years (in a scenario where the attack effect is based on observed lodgepole pine response. Responses to beetle attack depend on the extent of previous mortality and the number of trees under attack in a given year, which can vary greatly over space and time. Simulated enhancements peak in 2004 (British Columbia and 2008 (US. Responses to beetle attack are shown to be substantially larger (up to a 3-fold localized increase in summertime SOA concentrations in a scenario based on bark-beetle attack in spruce trees. Placed in the context of observations from the IMPROVE network, the changes in SOA concentrations due to beetle attack are in most cases small compared to the large annual and interannual variability in total organic aerosol which is driven by wildfire activity in western North America. This indicates that most beetle-induced SOA changes are not likely detectable in current observation networks; however, these changes may impede efforts to achieve natural visibility conditions in the national parks and wilderness
Heck, M. D.; Roberts, D. A.; Miller, D. L.; Tane, Z.
Under normal circumstances, the bark beetles of the Sierra Nevada conifer forests are vital to ecosystem health; by eliminating weak trees, they allow other plants to grow in the space left behind, provide homes for various animals, and enrich the soil. However, climate change is putting these ecosystems at risk: warmer winters allow bark beetles to be active and breed year-round, and the severe drought conditions currently present in California leave otherwise healthy trees unable to defend against attacks. In this study, we used Google Earth and Landsat-8 imagery of the Sierra National Forest to locate trees that had been damaged by bark beetles between the summers of 2015 and 2016. Additionally, we used an Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) image from summer of 2015 to look for a difference in the spectra of consistently healthy trees compared to spectra of trees which appeared healthy in 2015 but died in 2016. We found that healthy trees were consistently brighter across the spectrum than dying trees. Comparisons using t-tests were made between elevations, slopes, aspects, and spectral indices of a form (Band 1 - Band 2)/(Band 1 + Band 2) on our AVIRIS data. While we were unable to find any specific indices which indicate beetle kills, wavelengths in the ranges of 400-500 and 2200-2500 nanometers showed the most sensitivity when the brightness difference was scaled and removed.
Raffa, Kenneth F
Chemical signaling mediates nearly all aspects of species interactions. Our knowledge of these signals has progressed dramatically, and now includes good characterizations of the bioactivities, modes of action, biosynthesis, and genetic programming of numerous compounds affecting a wide range of species. A major challenge now is to integrate this information so as to better understand actual selective pressures under natural conditions, make meaningful predictions about how organisms and ecosystems will respond to a changing environment, and provide useful guidance to managers who must contend with difficult trade-offs among competing socioeconomic values. One approach is to place stronger emphasis on cross-scale interactions, an understanding of which can help us better connect pattern with process, and improve our ability to make mechanistically grounded predictions over large areas and time frames. The opportunity to achieve such progress has been heightened by the rapid development of new scientific and technological tools. There are significant difficulties, however: Attempts to extend arrays of lower-scale processes into higher scale functioning can generate overly diffuse patterns. Conversely, attempts to infer process from pattern can miss critically important lower-scale drivers in systems where their biological and statistical significance is negated after critical thresholds are breached. Chemical signaling in bark beetle - conifer interactions has been explored for several decades, including by the two pioneers after whom this award is named. The strong knowledge base developed by many researchers, the importance of bark beetles in ecosystem functioning, and the socioeconomic challenges they pose, establish these insects as an ideal model for studying chemical signaling within a cross-scale context. This report describes our recent work at three levels of scale: interactions of bacteria with host plant compounds and symbiotic fungi (tree level
Daniel R. Miller; Christopher M. Crowe
The multiple-funnel trap has gained broad acceptance for catching bark and ambrosia beetles since the trap was developed more than 25 years ago (Coleoptera: Scolytidae) (Lindgren 1983). The trap consists of black plastic funnels aligned vertically over each other, allowing for intercepted beetles to fall through the funnels into a wet or dry collection cup located on...
Full Text Available Symbioses between plants and microorganims have been fundamental in the evolution of both groups. The endophytic bacteria associated with conifers have been poorly studied in terms of diversity, ecology, and function. Coniferous trees of the genera Larix, Pseudotsugae, Picea and mainly Pinus, are hosts of many insects, including bark beetles and especially the Dendroctonus species. These insects colonize and kill these trees during their life cycle. Several bacteria detected in the gut and cuticle of these insects have been identified as endophytes in conifers. In this study, we characterized and compared the endophytic bacterial diversity in roots, phloem and bark of non-attacked saplings of Pinus arizonica and P. durangensis using 16S rRNA gene pyrosequencing. In addition, we evaluated the degree of taxonomic relatedness, and the association of metabolic function profiles of communities of endophytic bacteria and previously reported gut bacterial communities of D. rhizophagus; a specialized bark beetle that colonizes and kills saplings of these pine species. Our results showed that both pine species share a similar endophytic community. A total of seven bacterial phyla, 14 classes, 26 orders, 43 families, and 51 genera were identified. Enterobacteriaceae was the most abundant family across all samples, followed by Acetobacteraceae and Acidobacteriaceae, which agree with previous studies performed in other pines and conifers. Endophytic communities and that of the insect gut were significantly different, however, the taxonomic relatedness of certain bacterial genera of pines and insect assemblages suggested that some bacteria from pine tissues might be the same as those in the insect gut. Lastly, the metabolic profile using PICRUSt showed there to be a positive association between communities of both pines and insect gut. This study represents the baseline into the knowledge of the endophytic bacterial communities of two of the major hosts
Gonzalez-Escobedo, Roman; Briones-Roblero, Carlos I; Pineda-Mendoza, Rosa M; Rivera-Orduña, Flor N; Zúñiga, Gerardo
Symbioses between plants and microorganims have been fundamental in the evolution of both groups. The endophytic bacteria associated with conifers have been poorly studied in terms of diversity, ecology, and function. Coniferous trees of the genera Larix , Pseudotsugae , Picea and mainly Pinus , are hosts of many insects, including bark beetles and especially the Dendroctonus species. These insects colonize and kill these trees during their life cycle. Several bacteria detected in the gut and cuticle of these insects have been identified as endophytes in conifers. In this study, we characterized and compared the endophytic bacterial diversity in roots, phloem and bark of non-attacked saplings of Pinus arizonica and P. durangensis using 16S rRNA gene pyrosequencing. In addition, we evaluated the degree of taxonomic relatedness, and the association of metabolic function profiles of communities of endophytic bacteria and previously reported gut bacterial communities of D. rhizophagus ; a specialized bark beetle that colonizes and kills saplings of these pine species. Our results showed that both pine species share a similar endophytic community. A total of seven bacterial phyla, 14 classes, 26 orders, 43 families, and 51 genera were identified. Enterobacteriaceae was the most abundant family across all samples, followed by Acetobacteraceae and Acidobacteriaceae, which agree with previous studies performed in other pines and conifers. Endophytic communities and that of the insect gut were significantly different, however, the taxonomic relatedness of certain bacterial genera of pines and insect assemblages suggested that some bacteria from pine tissues might be the same as those in the insect gut. Lastly, the metabolic profile using PICRUSt showed there to be a positive association between communities of both pines and insect gut. This study represents the baseline into the knowledge of the endophytic bacterial communities of two of the major hosts affected by D
Morgan, Andy J.
The San Bernardino National Forest (SBNF) has experienced periods of high, concentrated bark beetle epidemics in the late 1990's and into the 2000's. This increased activity has caused huge amounts of forest loss, resulting from disease introduced by bark beetles. Using remote sensing techniques and Landsat Thematic Mapper 5 (TM5) imagery, the spread of bark beetle diseased trees is mapped over a period from 1998 to 2008. Acreage of two attack stages (red and gray) were calculated from a level sliced classification method developed on data training sites. In each image using Normalized Difference Vegetation Index (NDVI) is the driver of forest health classifications. The results of the analysis are classification maps for each year, red acreage estimated for each study year, and gray attack acreage estimated for each study year. Additionally, for the period of 2001-2004, acreage was compared to those reported by the USDA with a thirteen percent lower mortality total in comparison to USDA federal land and a thirty-two percent lower total mortality (federal and non-federal) land in the SBNF.
Avera, B.; Rhoades, C.; Paul, E. A.; Cotrufo, M. F.
In recent decades, bark beetle outbreaks have caused high levels of tree mortality in lodgepole pine (Pinus contorta) dominated forests across western North America. Previous work has found increased soil mineral nitrogen (N) with tree mortality in beetle infested stands, but surprisingly little change in stream N export. These findings suggest an important role of residual live vegetation and altered soil microbial response for retaining surplus N and mitigating N losses from disturbed lodgepole forests. Post outbreak salvage of merchantable timber reduces fuel levels and promotes tree regeneration; however, the implications of the combined bark beetle and harvesting disturbances on ecosystem N retention and productivity are uncertain. To advance understanding of post-disturbance N retention we compare unlogged beetle-infested forests and salvage logged stands with post-harvest woody residue retention or removal. We applied 15N-labeled (2 atom%) and natural abundance ammonium sulfate to eight year old lodgepole pine seedlings in three replicate plots of the three forest management treatments. This approach allows us to quantify the relative contributions of N retention in soil, microbial biomass, and plant tissue. Our study targets gaps in understanding of the processes that regulate N utilization and transfer between soil and vegetation that result in effective N retention in lodgepole pine ecosystems. These findings will also help guide forest harvest and woody residue management practices in order to maintain soil productivity.
Sheryl L. Costello; William R. Jacobi; Jose F. Negron
Wood borers (Coleoptera: Cerambycidae and Buprestidae) and bark beetles (Coleoptera: Curculionidae) infest ponderosa pines, Pinus ponderosa P. Lawson and C. Lawson, killed by mountain pine beetle (MPB), Dendroctonus ponderosae Hopkins, and fire. No data is available comparing wood borer and bark beetle densities or species guilds associated with MPB-killed or fire-...
Full Text Available Automatic identification of forest patches disturbed by the spruce bark beetle Ips typographus L. is crucial to reveal the rules of following bark beetle outbreaks on the landscape scale. Landsat imagery provides free resources to outline past and present gradations of bark beetle outbreaks (BBOs. The objective of this study is to identify the most sensitive vegetation index through different method of vegetation index differencing to identify past and actual bark beetle outbreaks. Six Landsat Thematic Mapper (TM images, from 2005–2009 and 2011, were converted into selected vegetation indices (VIs sensitive to conifer tree health in a Norway spruce–dominated forest in the High Tatra Mountains. The Vegetation Condition Index (VCI, Moisture Stress Index (MSI, Normalised Difference Moisture Index (NDMI, Normalised Difference Vegetation Index (NDVI, Disturbance Index (DI and Changed Disturbance Index (DI´ were calculated separately for every year, and the methodology of vegetation index differencing was applied to multiple two-year time periods (2005–2006, 2006–2007, 2007–2008, 2008–2009 and 2010–2011, thus producing the Changed Vegetation Index (ΔVI. A set of thresholds was established on ΔVI to classify disturbed and undisturbed forest due to BBOs; the sensitivity of different VIs to identify BBO was equally evaluated. The highest accuracies of classifications were reached in 2007 and 2011 (kappa index of agreement >70% and >40%, respectively, which were characterised by an epidemic phase of a BBO. All selected VIs were highly sensitive to BBOs, except for NDVI. The stable threshold value for change detection is not widely applicable to detect past forest disturbances caused by bark beetles, however. Finally, for further research of the epidemic phases of BBOs, we recommend the utilisation of the vegetation indices VCI, MSI and NDMI to detect BBOs because of their simplicity and easy interpretability.
Full Text Available Abstract Background Grosmannia clavigera is a bark beetle-vectored fungal pathogen of pines that causes wood discoloration and may kill trees by disrupting nutrient and water transport. Trees respond to attacks from beetles and associated fungi by releasing terpenoid and phenolic defense compounds. It is unclear which genes are important for G. clavigera's ability to overcome antifungal pine terpenoids and phenolics. Results We constructed seven cDNA libraries from eight G. clavigera isolates grown under various culture conditions, and Sanger sequenced the 5' and 3' ends of 25,000 cDNA clones, resulting in 44,288 high quality ESTs. The assembled dataset of unique transcripts (unigenes consists of 6,265 contigs and 2,459 singletons that mapped to 6,467 locations on the G. clavigera reference genome, representing ~70% of the predicted G. clavigera genes. Although only 54% of the unigenes matched characterized proteins at the NCBI database, this dataset extensively covers major metabolic pathways, cellular processes, and genes necessary for response to environmental stimuli and genetic information processing. Furthermore, we identified genes expressed in spores prior to germination, and genes involved in response to treatment with lodgepole pine phloem extract (LPPE. Conclusions We provide a comprehensively annotated EST dataset for G. clavigera that represents a rich resource for gene characterization in this and other ophiostomatoid fungi. Genes expressed in response to LPPE treatment are indicative of fungal oxidative stress response. We identified two clusters of potentially functionally related genes responsive to LPPE treatment. Furthermore, we report a simple method for identifying contig misassemblies in de novo assembled EST collections caused by gene overlap on the genome.
Gene D. Amman; Mark D. McGregor; Robert E. Jr. Dolph
The mountain pine beetle, Dendroctonus ponderosae Hopkins, is a member of a group of beetles known as bark beetles: Except when adults emerge and attack new trees, the mountain pine beetle completes its life cycle under the bark. The beetle attacks and kills lodgepole, ponderosa, sugar, and western white pines. Outbreaks frequently develop in lodgepole pine stands that...
Full Text Available The eight-toothed spruce bark beetle (Ips typographus is the most serious insect pest in Central European forests. During the past two decades, extreme meteorological events and subsequent beetle infestations have killed millions of cubic meters of standing spruce trees. Not all the infested stands could be cleared in time, and priorities in management had to be set. Natural or man-made buffer zones of about 500 meters in width are frequently defined to separate differently managed stands in Central Europe. While the buffer zones seem to be effective in most of the cases, their impact has not been studied in detail. Beetle densities were therefore assessed in three case studies using pheromone traps along transects, leading from infested stands into spruce-free buffer zones. The results of the trap catches allow an estimation of the buffer zone influence on densities and the dispersal of Ips typographus. Beetle densities were found to decrease rapidly with increasing distance from the infested spruce stands. The trap catches were below high-risk thresholds within a few hundred meters of the infested stands. The decrease in catches was more pronounced in open land and in an urban area than in a broadleaf stand. Designed buffer zones of 500 m width without spruce can therefore very probably help to reduce densities of spreading beetles.
Cobb, F.W. Jr.; Wood, D.L.; Stark, R.W.; Parmeter, J.R. Jr.
The authors suggest that a reduction of oleoresin exudation pressure, quantity, rate of flow, and an increase in the propensity of oleoresin to crystallize, and a reduction in phloem and sapwood moisture content enhance successful establishment of the western pine beetle and mountain pine beetle in ponderosa pine injured by photochemical atmospheric pollution. Hypotheses are presented which relate these results to host susceptibility.
Christopher J. Fettig
Full Text Available Mechanical thinning and the application of prescribed fire are commonly used to restore fire-adapted forest ecosystems in the Western United States. During a 10-year period, we monitored the effects of fuel-reduction and forest-restoration treatments on levels of tree mortality in an interior ponderosa pine, Pinus ponderosa Dougl. ex Laws., forest in California. Twelve experimental plots, ranging in size from 77–144 ha, were established to create two distinct forest structural types: mid-seral stage (low structural diversity; LoD and late-seral stage (high structural diversity; HiD. Following harvesting, half of each plot was treated with prescribed fire (B. A total of 16,473 trees (8.7% of all trees died during the 10-year period. Mortality was primarily attributed to bark beetles (Coleoptera: Curculionidae, Scolytinae (10,655 trees, specifically fir engraver, Scolytus ventralis LeConte, mountain pine beetle, Dendroctonus ponderosae Hopkins, western pine beetle, D. brevicomis LeConte, pine engraver, Ips pini (Say, and, to a much lesser extent, Jeffrey pine beetle, D. jeffreyi Hopkins. Trees of all ages and size classes were killed, but mortality was concentrated in the smaller-diameter classes (19–29.2 and 29.3–39.3 cm at 1.37 m in height. Most mortality occurred three to five years following prescribed burns. Higher levels of bark beetle-caused tree mortality were observed on LoD + B (8.7% than LoD (4.2%. The application of these and other results to the management of interior P. ponderosa forests are discussed, with an emphasis on the maintenance of large trees.
René Alberto López Castilla
Full Text Available There are four pines species endemic from Cuba with width importance, from the Conservation of the Forest Genetic Resources at regional level to the mitigation of the climatic change. Their economical importance is due to forming pure forest stand of fast growth and of straight trunk. The bark beetle of the genus Ips De Geer (Coleoptera: Scolytidae and the associate mushrooms from the complex Ophiostomatoid (Ceratocystidaceae: Microascales Phylum Ascomycotina are those that cause the biggest damages in the plantations of pines in Cuba. The damage management was based mainly on the logging of all the infested trees and the application of organosintetic insecticides with the consequent affectations to the environment apart from economic losses. In this work were determined the most noxious Ips species and the most vulnerable pine species by means of the development of experiments with randomized design on logging of pines and systematic samplings in pine trees in the western region. It was also defined a threshold of damage index and the most effective treatment with biological products in the central region. These results were integrated and introduced like a methodology of bark beetle management in a plantations area of Pinus caribaea Morelet. var caribaea (Punta Felipe, Villa Clara, Cuba after the development of an outbreak of this noxious complex and it was demonstrated that it was possible to control this forest pest without carrying out the logging of all the affected trees neither the application of organosintetic insecticides. As what this work has a positive environmental impact, contributing to the healthy conservation of the pine forests and an economic impact due to the saving of foreign currencies for concept of insecticides left of applying and also to diminish the losses of wooden increase.
Full Text Available In response to the information published in ‘Forest Research Papers’ (vol. 77(4, 2016, regarding the problem of the European spruce bark beetle Ips typographus (L. in the Białowieża Forest, we present our viewpoint on this issue. The role of the European spruce bark beetle in the Białowieża Forest is discussed based on the experience gained in Europe’s forests. We present the effects of I. typographus outbreaks on forest biodiversity as well as outbreak mitigation in the context of the processes taking place in semi-natural forests.
Kolařík, Miroslav; Kubátová, A.; Hulcr, J.; Pažoutová, Sylvie
Roč. 55, č. 1 (2008), s. 65-80 ISSN 0095-3628 R&D Projects: GA ČR GD206/03/H034; GA ČR GA522/02/1206; GA ČR(CZ) GD206/03/H137 Grant - others:GA UK(CZ) 205/2004 Institutional research plan: CEZ:AV0Z50200510 Keywords : geosmithia fungi * phloeophagous bark beetles * symbioses Subject RIV: EE - Microbiology, Virology Impact factor: 2.885, year: 2008
Jordal, Bjarte H; Cognato, Anthony I
Fungus farming is an unusual life style in insects that has evolved many times in the wood boring weevils named 'ambrosia beetles'. Multiple occurrences of this behaviour allow for a detailed comparison of the different origins of fungus farming through time, its directionality, and possible ancestral states. We tested these hypotheses with a phylogeny representing the largest data set to date, nearly 4 kb of nucleotides from COI, EF-1α, CAD, ArgK, 28S, and 200 scolytine taxa. Phylogenetic analyses using Bayesian or parsimony approaches placed the root of Scolytinae close to the tribe Scolytini and Microborus, but otherwise indicated low resolution at older nodes. More recent clades were well resolved, including ten origins of fungus farming. There were no subsequent reversals to bark or phloem feeding in the fungus farming clades. The oldest origin of fungus farming was estimated near 50 Ma, long after the origin of Scolytinae (100-120 Ma). Younger origins included the species rich Xyleborini, dated to 21 Ma. Sister group comparisons and test of independence between traits indicated that neither gregarious larval feeding nor regular inbreeding by sibling mating was strongly correlated with the origin of fungus farming. Origins of fungus farming corresponded mainly with two periods of global warming in the Cenozoic era, which were characterised by broadly distributed tropical forests. Hence, it seems likely that warm climates and expanding tropical angiosperm forests played critical roles in the successful radiation of diverse fungus farming groups. However, further investigation will likely reveal additional biological factors that promote fungus farming.
Ewers, B. E.; Pendall, E.; Norton, U.; Reed, D.; Franks, J.; Aston, T.; Whitehouse, F.; Barnard, H. R.; Brooks, P. D.; Angstmann, J.; Massman, W. J.; Williams, D. G.; Harpold, A. A.; Biederman, J.; Edburg, S. L.; Meddens, A. J.; Gochis, D. J.; Hicke, J. A.
The ongoing epidemic of bark beetles and their associated xylem blocking blue-stain fungi is unprecedented in Rocky Mountain subalpine forests. As this epidemic continues, we seek to improve our predictive understanding of coupled water, C and N cycles by quantifying how these cycles may become uncoupled in response to the outbreak. Our specific questions are 1) how does the rapid drop in individual tree transpiration impact the temporal and spatial extent of evapotranspiration and 2) how does the subsequent increase in soil moisture and lower C inputs and N uptake impact soil C and N fluxes? We address these questions in two forest ecosystems using eddy covariance, sap flux, leaf gas exchange, plant hydraulic conductance, vegetation characteristics and soil trace gas measurements. We applied two sampling designs 1) subdivide the lodgepole pine forest spatially into varying degrees of bark beetle and blue stain infection and 2) follow the fluxes as the outbreak continues at a point in space encompassing the range of spatial variability in mortality. The first order impact of the bark beetle and blue stain fungi is dramatic in all tree species with a greater than 50% reduction in transpiration per tree within a month of infection. This change occurs even before the characteristic red tinge occurs in the needles or before the sapwood is stained blue. Leaf stomatal conductance declines more than either the biochemical or light harvesting components of photosynthesis immediately after infestation. The annual C sink at the spruce/fir forest has declined from -2.88 to -0.57 Mg C ha-1 yr-1 from 2006 to 2009. Annual evapotranspiration (ET) over the last five years at the spruce/fir forest now has an inverse relationship with precipitation because the last two years have seen a dramatic decrease (from 73 to 59 cm/year) in ET while precipitation has increased (from ~100 to 140 cm/year). Soil moisture in both forests has increased up to 100% within one growing season in
Przybył, K; Karolewski, P; Oleksyn, J; Labedzki, A; Reich, P B
Fungi play an important role in leaf litter decomposition due to their ability to break down the lignocellulose matrix, which other organisms are unable to digest. However, little is known regarding the factors affecting components of fungal diversity. Here, we quantified richness of internal fungi in relation to litter nutrient and phenolic concentrations, sampling season (spring or fall), and premature leaf shedding due to low precipitation and infestation of bark beetles (mainly Ips typographus and Ips duplicatus). The study was conducted in 37-year-old Norway spruce [Picea abies (L.) Karst.] stands, with three plots each in mixed forest (MF) and coniferous forest (CF) site conditions in south-central Poland. Fifty-four species of sporulating fungi were identified in 2,330 freshly fallen needles sampled during 2003-2005, including 45 species in MF and 31 in CF. The significantly higher number of species in MF was likely related to moister conditions at that site. Among isolated fungi, 22% (12 species) were identified as endophytes of Norway spruce in prior studies. During spring of 2005, we found less than half the number of isolates and fungal species at each forest site as compared to fall for the two prior years. This pattern was observed in typical soil fungi (e.g., Penicillium daleae, Penicillium purpurogenum) and endophytes/epiphytes (e.g., Aureobasidium pullulans, Alternaria alternata, Cladosporium spp., and Lophodermium piceae). Premature shedding of needles was the most likely cause of this decline because it shortened the time period for fungi to infect green needles while on the tree. For all sites and sampling periods, richness of internal fungi was strongly and positively related to the age of freshly fallen litter (assessed using needle Ca concentration as a needle age tracer) and was also negatively related to litter phenolic concentration. Richness of internal fungi in freshly fallen litter may be adversely affected by low soil moisture status
Full Text Available Low-cost, miniaturized hyperspectral imaging technology is becoming available for small unmanned aerial vehicle (UAV platforms. This technology can be efficient in carrying out small-area inspections of anomalous reflectance characteristics of trees at a very high level of detail. Increased frequency and intensity of insect induced forest disturbance has established a new demand for effective methods suitable in mapping and monitoring tasks. In this investigation, a novel miniaturized hyperspectral frame imaging sensor operating in the wavelength range of 500–900 nm was used to identify mature Norway spruce (Picea abies L. Karst. trees suffering from infestation, representing a different outbreak phase, by the European spruce bark beetle (Ips typographus L.. We developed a new processing method for analyzing spectral characteristic for high spatial resolution photogrammetric and hyperspectral images in forested environments, as well as for identifying individual anomalous trees. The dense point clouds, measured using image matching, enabled detection of single trees with an accuracy of 74.7%. We classified the trees into classes of healthy, infested and dead, and the results were promising. The best results for the overall accuracy were 76% (Cohen’s kappa 0.60, when using three color classes (healthy, infested, dead. For two color classes (healthy, dead, the best overall accuracy was 90% (kappa 0.80. The survey methodology based on high-resolution hyperspectral imaging will be of a high practical value for forest health management, indicating a status of bark beetle outbreak in time.
Stephen P. Cook
Full Text Available Many of the forest soils in the Intermountain West are deficient in several nutrients, including nitrogen (N, potassium (K, sulfur (S and boron (B and these deficiencies may impact tree resistance to insect attack. Two potential techniques for manipulating tree resistance are fertilization and thinning. We examined fertilization (both alone and in conjunction with stand thinning. Conifer resistance to bark beetles involves a three-step response, the first stage of which is resin flow. Rapid resin flow can prevent the colonization of bark beetles within a tree. Fertilization with low levels of N resulted in an increase in resin flow while high levels of N did not significantly increase resin flow in treated trees. Thinning did not result in higher concentrations of foliar K or B but did result in higher concentrations of foliar N and S. The highest concentrations of foliar N and S consistently occurred in the trees from thinned treatments, regardless of fertilization. There was a negative correlation between tree growth and resin flow one year following treatments. Increasing available nutrient levels to trees (either through fertilization or stand density management may result in modified resistance parameters that must be considered when making management decisions.
Zeiri, A; Ahmed, M Z; Braham, M; Qiu, B-L
Scolytus amygdali is a polyphagous insect pest that feeds on fruit trees and forest trees. Our study assessed the host preference and reproductive potential of S. amygdali on four tree species: almond (Prunus dulcis), apricot (Prunus armeniaca), peach (Prunus persica), and plum (Prunus domestica). Females of S. amygdali produced maternal galleries that were longer on peach than the other three trees, and female fecundity was highest on peach. Females with longer maternal galleries produced more eggs, indicating a positive correlation between maternal gallery length and female fertility. The under-bark development time of S. amygdali is significantly shorter on plum (45 days) and almond (56 days) than on apricot (65 days) and peach (64 days). Despite this longer development time on peach, our results still suggest that, of the four types of tree tested, peach is the most preferred host for S. amygdali.
J.L. Hayes; J.E. Lundquist
The compilation of papers in this proceedings is based on a symposium sponsored by the Insect and Diseases Working Group (D5) at the 2007 Society of American Foresters (SAF) convention in Portland, Oregon. The selection of topics parallels the research priorities of the Western Bark Beetle Research Group (WBBRG) (USDA Forest Service, Research and Development), which...
Veselská, Tereza; Kolařík, Miroslav
Roč. 13, FEB 2015 (2015), s. 83-92 ISSN 1754-5048 R&D Projects: GA ČR(CZ) GAP506/11/2302 Institutional support: RVO:61388971 Keywords : Ambrosia fungi * Bark beetles * Conidial DNA content Subject RIV: EE - Microbiology, Virology Impact factor: 2.631, year: 2015
Charles J. Mason; Kier D. Klepzig; Brian J. Kopper; Philip J. Kersten; Barbara L. Illman; Kenneth F. Raffa
Conifers possess a suite of physiochemical defenses that protect their subcortical tissues from bark beetle -fungal complexes. These defenses include rapid induction of terpenoids and phenolics at the site of attack. Studies of the distribution, induction, and bioactivity of conifer terpenoids have focused heavily on monoterpenes. We assessed induction of diterpene...
Oulehle, Filip; Chuman, Tomáš; Majer, V.; Hruška, Jakub
Roč. 116, 1-3 (2013), s. 83-101 ISSN 0168-2563 Institutional support: RVO:67179843 Keywords : acidification * nitrogen saturation * aluminium * recovery * Bark beetle * land cover Subject RIV: EH - Ecology, Behaviour Impact factor: 3.730, year: 2013
Brian J. Kopper; Barbara L. Illman; Philip J. Kersten; Kier D. Klepzig; Kenneth F. Raffa
Conifer resin and phloem tissue contain several phytochemical groups, composed primarily of monoterpenes, diterpene acids, and stilbene phenolics. The effects of monoterpenes and phenolics on stem-colonizing bark beetles and their associated microorganisms have been studied to some extent, but the roles of diterpene acids are largely unknown. Diterpene acids are known...
Evidence for divergence in cuticular hydrocarbon sex pheromone between California and Mississippi (United States of America) populations of bark beetle parasitoid Roptrocerus xylophagorum (Hymenoptera: Pteromalidae).
Brian Sullivan; Nadir Erbilgin
Roptrocerus xylophagorum (Ratzeburg) (Hymenoptera: Pteromalidae) is a common Holarctic parasitoid of the larvae and pupae of bark beetles (Coleoptera: Curculionidae: Scotytinae). In no-choice laboratory bioassays, we found that male wasps derived either from northern California or southwestern Mississippi, United States of America more frequently displayed sexual...
The coffee berry borer, Hypothenemus hampei(Coleoptera: Curculionidae)(Ferrari), is a serious pest of coffee worldwide and has been recently introduced in Hawai’i, first detected in the state in 2010. Adult silvanid flat bark beetles, Cathartus quadricollis (Coleoptera: Silvanidae) and adult laemoph...
Kaňa, Jiří; Tahovská, K.; Kopáček, Jiří; Šantrůčková, H.
Roč. 10, č. 7 (2015), e0134165 E-ISSN 1932-6203 R&D Projects: GA ČR(CZ) GAP504/12/1218 Institutional support: RVO:60077344 Keywords : N-saturation * bark beetle outbreak * soil microbial biomass * nitrification * ammonification * DOC * nitrate Subject RIV: EH - Ecology, Behaviour Impact factor: 3.057, year: 2015
Pfammatter, Jesse A; Coyle, David R; Gandhi, Kamal J K; Hernandez, Natalie; Hofstetter, Richard W; Moser, John C; Raffa, Kenneth F
Mites associated with subcortical beetles feed and reproduce within habitats transformed by tree-killing herbivores. Mites lack the ability to independently disperse among these habitats, and thus have evolved characteristics that facilitate using insects as transport between resources. Studies on associations between mites and beetles have historically been beetle-centric, where an assemblage of mite species is characterized on a single beetle species. However, available evidence suggests there may be substantial overlap among mite species on various species of beetles utilizing similar host trees. We assessed the mite communities of multiple beetle species attracted to baited funnel traps in Pinus stands in southern Wisconsin, northern Arizona, and northern Georgia to better characterize mite dispersal and the formation of mite-beetle phoretic associations at multiple scales. We identified approximately 21 mite species totaling 10,575 individuals on 36 beetle species totaling 983 beetles. Of the mites collected, 97% were represented by eight species. Many species of mites were common across beetle species, likely owing to these beetles' common association with trees in the genus Pinus. Most mite species were found on at least three beetle species. Histiostoma spp., Iponemus confusus Lindquist, Histiogaster arborsignis Woodring and Trichouropoda australis Hirschmann were each found on at least seven species of beetles. While beetles had largely similar mite membership, the abundances of individual mite species were highly variable among beetle species within each sampling region. Phoretic mite communities also varied within beetle species between regions, notably for Ips pini (Say) and Ips grandicollis (Eichhoff). © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: email@example.com.
Briones-Roblero, Carlos Iván; Hernández-García, Juan Alfredo; Gonzalez-Escobedo, Roman; Soto-Robles, L Viridiana; Rivera-Orduña, Flor N; Zúñiga, Gerardo
Bark beetles play an important role as agents of natural renovation and regeneration in coniferous forests. Several studies have documented the metabolic capacity of bacteria associated with the gut, body surface, and oral secretions of these insects; however, little is known about how the bacterial community structure changes during the life cycle of the beetles. This study represents the first comprehensive analysis of the bacterial community of the gut of the bark beetle D. rhizophagus during the insect's life cycle using 454 pyrosequencing. A total of 4 bacterial phyla, 7 classes, 15 families and 23 genera were identified. The α-diversity was low, as demonstrated in previous studies. The dominant bacterial taxa belonged to the Enterobacteriaceae and Pseudomonadaceae families. This low α-diversity can be attributed to the presence of defensive chemical compounds in conifers or due to different morpho-physiological factors in the gut of these insects acting as strong selective factors. Members of the genera Rahnella, Serratia, Pseudomonas and Propionibacterium were found at all life stages, and the first three genera, particularly Rahnella, were predominant suggesting the presence of a core microbiome in the gut. Significant differences in β-diversity were observed, mainly due to bacterial taxa present at low frequencies and only in certain life stages. The predictive functional profiling indicated metabolic pathways related to metabolism of amino acids and carbohydrates, and membrane transport as the most significant in the community. These differences in the community structure might be due to several selective factors, such as gut compartmentalization, physicochemical conditions, and microbial interactions.
Carlos Iván Briones-Roblero
Full Text Available Bark beetles play an important role as agents of natural renovation and regeneration in coniferous forests. Several studies have documented the metabolic capacity of bacteria associated with the gut, body surface, and oral secretions of these insects; however, little is known about how the bacterial community structure changes during the life cycle of the beetles. This study represents the first comprehensive analysis of the bacterial community of the gut of the bark beetle D. rhizophagus during the insect's life cycle using 454 pyrosequencing. A total of 4 bacterial phyla, 7 classes, 15 families and 23 genera were identified. The α-diversity was low, as demonstrated in previous studies. The dominant bacterial taxa belonged to the Enterobacteriaceae and Pseudomonadaceae families. This low α-diversity can be attributed to the presence of defensive chemical compounds in conifers or due to different morpho-physiological factors in the gut of these insects acting as strong selective factors. Members of the genera Rahnella, Serratia, Pseudomonas and Propionibacterium were found at all life stages, and the first three genera, particularly Rahnella, were predominant suggesting the presence of a core microbiome in the gut. Significant differences in β-diversity were observed, mainly due to bacterial taxa present at low frequencies and only in certain life stages. The predictive functional profiling indicated metabolic pathways related to metabolism of amino acids and carbohydrates, and membrane transport as the most significant in the community. These differences in the community structure might be due to several selective factors, such as gut compartmentalization, physicochemical conditions, and microbial interactions.
Meddens, A. J.; Hicke, J. A.; Edburg, S. L.; Lawrence, D. M.
Wildfires and bark beetle outbreaks cause major forest disturbances in the western US, affecting ecosystem productivity and thereby impacting forest carbon cycling and future climate. Despite the large spatial extent of tree mortality, quantifying carbon flux dynamics following fires and bark beetles over larger areas is challenging because of forest heterogeneity, varying disturbance severities, and field observation limitations. The objective of our study is to estimate these dynamics across the western US using the Community Land Model (version CLM4.5-BGC). CLM4.5-BGC is a land ecosystem model that mechanistically represents the exchanges of energy, water, carbon, and nitrogen with the atmosphere. The most recent iteration of the model has been expanded to include vertically resolved soil biogeochemistry and includes improved nitrogen cycle representations including nitrification and denitrification and biological fixation as well as improved canopy processes including photosynthesis. Prior to conducting simulations, we modified CLM4.5-BGC to include the effects of bark beetle-caused tree mortality on carbon and nitrogen stocks and fluxes. Once modified, we conducted paired simulations (with and without) fire- and bark beetle-caused tree mortality by using regional data sets of observed mortality as inputs. Bark beetle-caused tree mortality was prescribed from a data set derived from US Forest Service aerial surveys from 1997 to 2010. Annual tree mortality area was produced from observed tree mortality caused by bark beetles and was adjusted for underestimation. Fires were prescribed using the Monitoring Trends in Burn Severity (MTBS) database from 1984 to 2010. Annual tree mortality area was produced from forest cover maps and inclusion of moderate- and high-severity burned areas. Simulations show that maximum yearly reduction of net ecosystem productivity (NEP) caused by bark beetles is approximately 20 Tg C for the western US. Fires cause similar reductions
Jennifer Klutsch; Nadir Erbilgin
In recent decades, climate change has facilitated shifts in species ranges that have the potential to significantly affect ecosystem dynamics and resilience. Mountain pine beetle (Dendroctonus ponderosae) is expanding east from British Columbia, where it has killed millions of pine trees, primarily lodgepole pine (Pinus contorta...
Obregón-Molina, G; Cesar-Ayala, A K; López, M F; Cano-Ramírez, C; Zúñiga, G
Bark beetles of the genus Dendroctonus are important components of coniferous forests. During host colonization, they must overcome the chemical defences of their host trees, which are metabolized by cytochrome P450 (CYP or P450) enzymes to compounds that are readily excreted. In this study, we report the relative expression (quantitative real-time PCR) of four orthologous cytochrome P450 genes (CYP6BW5, CYP6DG1, CYP6DJ2 and CYP9Z20) in Dendroctonus rhizophagus and Dendroctonus valens forced to attack host trees at 8 and 24 h following forced attack and in four stages during natural colonization [solitary females boring the bark (T1); both male and female members of couples before oviposition (T2); both male and female members of couples during oviposition (T3), and solitary females inside the gallery containing eggs (T4)]. For both species gene expression was different compared with that observed in insects exposed to single monoterpenes in the laboratory, and the expression patterns were significantly different amongst species, sex, gut region and exposure time or natural colonization stage. The induction of genes (CYP6BW5v1, CYP6DJ2v1 and CYP9Z20v1 from D. rhizophagus, as well as CYP6DG1v3 from D. valens) correlated with colonization stage as well as with the increase in oxygenated monoterpenes in the gut of both species throughout the colonization of the host. Our results point to different functions of these orthologous genes in both species. © 2015 The Royal Entomological Society.
Romón, Pedro; Iturrondobeitia, Juan Carlos; Gibson, Ken; Lindgren, B Staffan; Goldarazena, Arturo
The association between 11 species of bark beetles (Coleoptera: Scolytinae) and one weevil (Coleoptera: Entiminae) with the pitch canker fungus, Fusarium circinatum Nirenberg and O'Donnell, was determined by crushing beetles on selective medium and histone H3 gene sequencing. Pityophthorus pubescens (Marsham) (25.00%), Hylurgops palliatus (Gyllenhal) (11.96%), Ips sexdentatus (Börner) (8.57%), Hypothenemus eruditus Westwood (7.89%), Hylastes attenuatus Erichson (7.40%), and Orthotomicus erosus (Wollaston) (2.73%) were found to carry the inoculum. In addition, the root weevil Brachyderes incanus L. (14.28%) had the second highest frequency of occurrence of the fungus. The responses of the insects to a range of verbenone doses were tested in field bioassays using funnel traps. Catches of P. pubescens, a species colonizing branch tips of live trees, were significantly reduced in a log-linear dose-dependent relationship. Catches of I. sexdentatus, an opportunistic species normally attacking fresh dead host material, were also gradually reduced with increasing verbenone dose. Catches of Tomicus piniperda L., O. erosus, Dryocoetes autographus (Ratzeburg), H. eruditus, Xyleborus dryographus (Ratzeburg), Hylastes ater (Paykull), Hylurgus ligniperda (F.), H. attenuatus, and B. incanus were not significantly affected by verbenone. The effects of verbenone were consistent with differences in host-age preference. Semiochemical disruption by verbenone in P. pubescens and I. sexdentatus could represent an integrated pest management strategy for the prevention of the spread of pitch canker disease between different stands. However, several species associated with F. circinatum were unaffected by verbenone, not supporting this compound for prevention of the establishment of potential vectors in Northern Spain.
Hodgson, Erin W.; Drost, Dan
Asparagus beetle, Crioceris asparagi, and spotted asparagus beetle, C. duodecimpunctata are leaf beetles in the family Chrysomelidae. These beetles feed exclusively on asparagus and are native to Europe. Asparagus beetle is the more economically injurious of the two species.
Toffin, Etienne; Gabriel, Edith; Louis, Marceau; Deneubourg, Jean-Louis; Grégoire, Jean-Claude
Bark beetles use aggregation pheromones to promote group foraging, thus increasing the chances of an individual to find a host and, when relevant, to overwhelm the defences of healthy trees. When a male beetle finds a suitable host, it releases pheromones that attract potential mates as well as other 'spying' males, which result in aggregations on the new host. To date, most studies have been concerned with the use of aggregation pheromones by bark beetles to overcome the defences of living, well-protected trees. How insects behave when facing undefended or poorly defended hosts remains largely unknown. The spatio-temporal pattern of resource colonization by the European eight-toothed spruce bark beetle, Ips typographus , was quantified when weakly defended hosts (fallen trees) were attacked. In many of the replicates, colonization began with the insects rapidly scattering over the available surface and then randomly filling the gaps until a regular distribution was established, which resulted in a constant decrease in nearest-neighbour distances to a minimum below which attacks were not initiated. The scattered distribution of the first attacks suggested that the trees were only weakly defended. A minimal theoretical distance of 2.5 cm to the earlier settlers (corresponding to a density of 3.13 attacks dm -2 ) was calculated, but the attack density always remained lower, between 0.4 and 1.2 holes dm -2 , according to our observations.
Full Text Available The aim of this study was to investigate and to compare the extractability, bioaccessibility, and bioavailability in vitro of antioxidative compounds from bark of selected Salix species: S. alba (SA, S. daphnoides (SD, S. purpurea (SP, and S. daphnoides x purpurea (SDP hybrid willow clones originating from their natural habitats and cultivated on the sandy soil. The highest amount of phenolic glycosides was found in the bark of SDP and SD. The best source of phenolics was bark of SDP. The highest content of flavonoids were found in SD bark samples, whereas the highest concentration of bioaccessible and bioavailable phenolic acids was determined in SDP bark. Bark of all tested Salix species showed significant antiradical activity. This properties are strongly dependent on extraction system and genetic factors. Regardless of Salix genotypes, the lowest chelating power was found for chemically-extractable compounds. Bark of all Salix species contained ethanol-extractable compounds with reducing ability. Besides this, high bioaccessibility and bioavailability in vitro of Salix bark phytochemicals were found. Obtained results indicate that extracts from bark tested Salix genotypes can provide health promoting benefits to the consumers; however, this problem requires further study.
Lindeman, Amanda A; Yack, Jayne E
Acoustic signals are commonly used by insects in the context of mating, and signals can vary depending on the stage of interaction between a male and female. While calling songs have been studied extensively, particularly in the Orthoptera, much less is known about courtship songs. One outstanding question is how potential mates are differentiated by their courtship signal characteristics. We examined acoustic courtship signals in a new system, bark beetles (Scolytinae). In the red turpentine beetle (Dendroctonus valens) males produce chirp trains upon approaching the entrance of a female's gallery. We tested the hypotheses that acoustic signals are honest indicators of male condition and that females choose males based on signal characteristics. Males generated two distinct chirp types (simple and interrupted), and variability in their prevalence correlated with an indicator of male quality, body size, with larger males producing significantly more interrupted chirps. Females showed a significant preference for males who produced interrupted chirps, suggesting that females distinguish between males on the basis of their chirp performances. We suggest that interrupted chirps during courtship advertise a male's size and/or motor skills, and function as the proverbial 'passwords' that allow him entry to a female's gallery. Copyright © 2015 Elsevier B.V. All rights reserved.
Arnberger, Arne; Ebenberger, Martin; Schneider, Ingrid E.; Cottrell, Stuart; Schlueter, Alexander C.; von Ruschkowski, Eick; Venette, Robert C.; Snyder, Stephanie A.; Gobster, Paul H.
Extensive outbreaks of tree-killing insects are increasing across forests in Europe and North America due to climate change and other factors. Yet, little recent research examines visitor response to visual changes in conifer forest recreation settings resulting from forest insect infestations, how visitors weigh trade-offs between physical and social forest environment factors, or how visitor preferences might differ by nationality. This study explored forest visitor preferences with a discrete choice experiment that photographically simulated conifer forest stands with varying levels of bark beetle outbreaks, forest and visitor management practices, and visitor use levels and compositions. On-site surveys were conducted with visitors to State Forest State Park in Colorado ( n = 200), Lake Bemidji State Park in Minnesota ( n = 228), and Harz National Park in Germany ( n = 208). Results revealed that the condition of the immediate forest surrounding was the most important variable influencing visitors' landscape preferences. Visitors preferred healthy mature forest stands and disliked forests with substantial dead wood. The number of visitors was the most important social factor influencing visitor landscape preferences. Differences in the influence of physical and social factors on visual preferences existed between study sites. Findings suggest that both visual forest conditions and visitor use management are important concerns in addressing landscape preferences for beetle-impacted forest recreation areas.
Full Text Available In 2010-2012, investigations on Ips typographus populations were carried out in Norway spruce stands recently affected by bark beetle outbreak in the Beskid Żywiecki Mts. in Poland. The aim of the study was to test the usefulness of several traits describing I. typographus populations for evaluation of their actual outbreak tendency. Infestation density, sex ratio, gallery length, progeny number and beetle length were used as the traits. Trait variability was analyzed in relation to infested tree mortality in the current year of observation and outbreak tendency defined by the comparison of data on tree mortality in the current year and that in the year before.
Full Text Available The Almond bark beetle Scolytus amygdali Guerin-Meneville, 1847 is a serious beetle that can affect important economic crops in Tunisia. The species is morphologically similar to other bark beetles attacking fruit trees such as Scolytus mediterraneus. The gallery systems of both species are also generally hard to differentiate. A detailed study about gallery systems has carried out in the central region of Tunisia in order to give more details on beetle damage under the bark. Maternal and larval galleries from infested branches of almond were examined and measured. It is hoped that these details of the shape and measurements of the gallery systems of Scolytus amygdali will facilitate the identification of infestations of almond bark beetles attacking fruit trees in Tunisia.
Richard H. Smith
The Jeffrey pine beetle (Dendroctonus jeffreyi Hopk.), one of the bark beetles that kill trees by mining between the bark and the wood, is the principal insect enemy of Jeffrey pine. The beetle is of economic importance chiefly in California, where most of the Jeffrey pine grows, and is most destructive in old-growth stands in the timber-producing areas of northeastern...
Ewers, B. E.; Peckham, S. D.; Mackay, D. S.; Pendall, E.; Frank, J. M.; Massman, W. J.; Reed, D. E.; Borkhuu, B.
In recent decades, bark beetle infestation in western North America has reached epidemic levels. The resulting widespread forest mortality may have profound effects on present and future water and carbon cycling with potential negative consequences to a region that relies on water from montane and subalpine watersheds. We simulated stand-level ecosystem fluxes of water and carbon at two bark beetle-attacked conifer forests in southeast Wyoming, USA. The lower elevation site dominated by lodgepole pine (Pinus contorta) was attacked by mountain pine beetle (Dendroctonus ponderosae) during 2008-2010. The high elevation Engelmann spruce (Picea engelmannii) dominated site was attacked by the spruce beetle (Dendroctonus rufipennis) during roughly the same time period. Both beetle infestations resulted in >60% canopy mortality in the footprint of eddy covariance towers located at each site. However, carbon and water fluxes responses to mortality depended on the forest type. Using data collected at the sites, we scaled simulated plant hydraulic conductivity by either percent canopy mortality or loss of live tree basal area during infestation. We also simulated a case of no beetle attack. At the lodgepole site, the no-beetle model best fit the data and showed no significant change in growing season carbon flux and a 15% decrease in evapotranspiration (ET). However, at the spruce site, the simulation that tracked canopy loss agreed best with observations: carbon flux decreased by 72% and ET decreased by 31%. In the lodgepole stand, simulated soil water content agreed with spatially distributed measurements that were weighted to reflect overall mortality in the tower footprint. Although these two forest ecosystems are only 20 km apart, separated by less than 300m in elevation, and have been impacted by similar mortality agents, the associated changes in carbon and water cycling are significantly different. Beetle effects on hydrologic cycling were greatest at high elevation
Full Text Available Six types of pheromone traps were tested between 2012 and 2014 in the High Tatra Mountains, northern Slovakia. Traps were baited with lures for attracting the European spruce bark beetle (Ips typographus L. (Coleoptera: Curculionidae, Scolytinae. Among the tested traps, four types are commercial products; Theysohn (T-trap, Ecotrap (E-trap, Lindgren funnel trap (L-trap, BEKA trap (B-trap and two are our newly developed models; Funnel trap (P-trap and Cross trap (K-trap. The traps were set up on ten selected sites and tested during three growing seasons (2012, 2013 and 2014. The newly developed models were compared to the commercially available models for trapping efficiency of target pest, easy to use and impact on non-target insect species. We found that the best commercially available model is the L-trap, however the bottom of L-trap is considered too shallow resulting in an accumulation of rainwater that increases the traps attractiveness for Silphids. In our experiment, the newly developed models; P-trap and K-trap performed better compared to commercially used models. P-trap caught 28% more I. typographus and K-trap caught 57% more beetles compared to T-trap in 2014. There are additional advantages of the newly developed traps such as easy handling, good rainwater drainage, higher collection container volume, and scale marking within the collection container. The results of this study have encouraged us to patent P-trap and K-trap as utility models.
Kristen M. Waring; Diana L. Six
Whitebark pine (Pinus albicaulis Engelm.), an important component of high elevation ecosystems in the western United States and Canada, is declining due to fire exclusion, white pine blister rust (Cronartium ribicola J.C. Fisch.), and mountain pine beetle (Dendroctonus ponderosae Hopkins). This study was...
Bryon J. Collins; Chuck C. Rhoades; Michael A. Battaglia; Robert M. Hubbard
Most mature lodgepole pine (Pinus contorta var. latifolia Engelm. ex Wats.) forests in the central and southern Rocky Mountains originated after stand-replacing wildfires or logging (Brown 1975, Lotan and Perry 1983, Romme 1982). In recent years, mountain pine beetle (Dendroctonus ponderosae Hopkins) outbreaks have created a widespread, synchronous disturbance (i.e.,...
Peter L. Lorio; Frederick M. Stephen; Timothy D. Paine
We evaluated the impact of tree resistance on within-tree population dynamics of southern pine beetle, Dendroctonus frontalis Zimm. (Coleoptera: Scolytidae) in loblolly pine, Pinus taeda L., as affected by prevailing water regimes, acute water deficits imposed by applying dry-ice (solid CO2) collars to tree boles, and by the seasonal ontogeny of...
Berner, Logan T.; Law, Beverly E.; Meddens, Arjan J. H.; Hicke, Jeffrey A.
High temperatures and severe drought contributed to extensive tree mortality from fires and bark beetles during the 2000s in parts of the western continental United States. Several states in this region have greenhouse gas (GHG) emission targets and would benefit from information on the amount of carbon stored in tree biomass killed by disturbance. We quantified mean annual tree mortality from fires, bark beetles, and timber harvest from 2003-2012 for each state in this region. We estimated tree mortality from fires and beetles using tree aboveground carbon (AGC) stock and disturbance data sets derived largely from remote sensing. We quantified tree mortality from harvest using data from US Forest Service reports. In both cases, we used Monte Carlo analyses to track uncertainty associated with parameter error and temporal variability. Regional tree mortality from harvest, beetles, and fires (MORTH+B+F) together averaged 45.8 ± 16.0 Tg AGC yr-1 (±95% confidence interval), indicating a mortality rate of 1.10 ± 0.38% yr-1. Harvest accounted for the largest percentage of MORTH+B+F (˜50%), followed by beetles (˜32%), and fires (˜18%). Tree mortality from harvest was concentrated in Washington and Oregon, where harvest accounted for ˜80% of MORTH+B+F in each state. Tree mortality from beetles occurred widely at low levels across the region, yet beetles had pronounced impacts in Colorado and Montana, where they accounted for ˜80% of MORTH+B+F. Tree mortality from fires was highest in California, though fires accounted for the largest percentage of MORTH+B+F in Arizona and New Mexico (˜50%). Drought and human activities shaped regional variation in tree mortality, highlighting opportunities and challenges to managing GHG emissions from forests. Rising temperatures and greater risk of drought will likely increase tree mortality from fires and bark beetles during coming decades in this region. Thus, sustained monitoring and mapping of tree mortality is necessary to
Jennifer Juzwik; Mark T. Banik; Sharon E. Reed; James T. English; Matthew D. Ginzel
The canker pathogen Geosmithia morbida is known to be transmitted to Juglans species by the bark beetle Pityophthorus juglandis, and to lead to development of thousand cankers disease. In an Indiana-wide trap-tree survey of ambrosia and bark beetles and weevils colonizing stressed Juglans nigra...
Jenicek, Michal; Matejka, Ondrej; Hotovy, Ondrej
The knowledge of water volume stored in the snowpack and its spatial distribution is important to predict the snowmelt runoff. The objective of this study was to quantify the role of different forest structures on the snowpack distribution at a plot scale during snow accumulation and snow ablation periods. Special interest was put in the role of the forest affected by the bark beetle (Ips typographus). We performed repeated detailed manual field survey at selected mountain plots with different canopy structure located at the same elevation and without influence of topography and wind on the snow distribution. The forest canopy structure was described using parameters calculated from hemispherical photographs, such as canopy closure, leaf area index (LAI) and potential irradiance. Additionally, we used shortwave radiation measured using CNR4 Net radiometers placed in plots with different canopy structure. Two snow accumulation and ablation models were set-up to simulate the snow water equivalent (SWE) in plots with different vegetation cover. First model was physically-based using the energy balance approach, second model was conceptual and it was based on the degree-day approach. Both models accounted for snow interception in different forest types using LAI as a parameter. The measured SWE in the plot with healthy forest was on average by 41% lower than in open area during snow accumulation period. The disturbed forest caused the SWE reduction by 22% compared to open area indicating increasing snow storage after forest defoliation. The snow ablation in healthy forest was by 32% slower compared to open area. On the contrary, the snow ablation in disturbed forest (due to the bark beetle) was on average only by 7% slower than in open area. The relative decrease in incoming solar radiation in the forest compared to open area was much bigger compared to the relative decrease in snowmelt rates. This indicated that the decrease in snowmelt rates cannot be explained only
Speckman, Heather N; Frank, John M; Bradford, John B; Miles, Brianna L; Massman, William J; Parton, William J; Ryan, Michael G
Eddy covariance nighttime fluxes are uncertain due to potential measurement biases. Many studies report eddy covariance nighttime flux lower than flux from extrapolated chamber measurements, despite corrections for low turbulence. We compared eddy covariance and chamber estimates of ecosystem respiration at the GLEES Ameriflux site over seven growing seasons under high turbulence [summer night mean friction velocity (u*) = 0.7 m s(-1)], during which bark beetles killed or infested 85% of the aboveground respiring biomass. Chamber-based estimates of ecosystem respiration during the growth season, developed from foliage, wood, and soil CO2 efflux measurements, declined 35% after 85% of the forest basal area had been killed or impaired by bark beetles (from 7.1 ± 0.22 μmol m(-2) s(-1) in 2005 to 4.6 ± 0.16 μmol m(-2) s(-1) in 2011). Soil efflux remained at ~3.3 μmol m(-2) s(-1) throughout the mortality, while the loss of live wood and foliage and their respiration drove the decline of the chamber estimate. Eddy covariance estimates of fluxes at night remained constant over the same period, ~3.0 μmol m(-2) s(-1) for both 2005 (intact forest) and 2011 (85% basal area killed or impaired). Eddy covariance fluxes were lower than chamber estimates of ecosystem respiration (60% lower in 2005, and 32% in 2011), but the mean night estimates from the two techniques were correlated within a year (r(2) from 0.18 to 0.60). The difference between the two techniques was not the result of inadequate turbulence, because the results were robust to a u* filter of >0.7 m s(-1). The decline in the average seasonal difference between the two techniques was strongly correlated with overstory leaf area (r(2) = 0.92). The discrepancy between methods of respiration estimation should be resolved to have confidence in ecosystem carbon flux estimates. © 2014 John Wiley & Sons Ltd.
Full Text Available Cattle farming is a major source of greenhouse gases (GHGs. Recent research suggests that GHG fluxes from dung pats could be affected by biotic interactions involving dung beetles. Whether and how these effects vary among beetle species and with assemblage composition is yet to be established. To examine the link between GHGs and different dung beetle species assemblages, we used a closed chamber system to measure fluxes of carbon dioxide (CO2, methane (CH4 and nitrous oxide (N2O from cattle dung pats. Targeting a total of four dung beetle species (a pat-dwelling species, a roller of dung balls, a large and a small tunnelling species, we ran six experimental treatments (four monospecific and two mixed and two controls (one with dung but without beetles, and one with neither dung nor beetles. In this setting, the overall presence of beetles significantly affected the gas fluxes, but different species contributed unequally to GHG emissions. When compared to the control with dung, we detected an overall reduction in the total cumulative CO2 flux from all treatments with beetles and a reduction in N2O flux from the treatments with the three most abundant dung beetle species. These reductions can be seen as beneficial ecosystem services. Nonetheless, we also observed a disservice provided by the large tunneler, Copris lunaris, which significantly increased the CH4 flux-an effect potentially traceable to the species' nesting strategy involving the construction of large brood balls. When fluxes were summed into CO2-equivalents across individual GHG compounds, dung with beetles proved to emit less GHGs than did beetle-free dung, with the mix of the three most abundant species providing the highest reduction (-32%. As the mix of multiple species proved the most effective in reducing CO2-equivalents, the conservation of diverse assemblages of dung beetles emerges as a priority in agro-pastoral ecosystems.
Griffin, Jacob M; Turner, Monica G
Outbreaks of Dendroctonus beetles are causing extensive mortality in conifer forests throughout North America. However, nitrogen (N) cycling impacts among forest types are not well known. We quantified beetle-induced changes in forest structure, soil temperature, and N cycling in Douglas-fir (Pseudotsuga menziesii) forests of Greater Yellowstone (WY, USA), and compared them to published lodgepole pine (Pinus contorta var. latifolia) data. Five undisturbed stands were compared to five beetle-killed stands (4-5 years post-outbreak). We hypothesized greater N cycling responses in Douglas-fir due to higher overall N stocks. Undisturbed Douglas-fir stands had greater litter N pools, soil N, and net N mineralization than lodgepole pine. Several responses to disturbance were similar between forest types, including a pulse of N-enriched litter, doubling of soil N availability, 30-50 % increase in understory cover, and 20 % increase in foliar N concentration of unattacked trees. However, the response of some ecosystem properties notably varied by host forest type. Soil temperature was unaffected in Douglas-fir, but lowered in lodgepole pine. Fresh foliar %N was uncorrelated with net N mineralization in Douglas-fir, but positively correlated in lodgepole pine. Though soil ammonium and nitrate, net N mineralization, and net nitrification all doubled, they remained low in both forest types (mineralization; litter and soil N cycling similarly in each forest type, despite substantial differences in pre-disturbance biogeochemistry. In contrast, soil temperature and soil N-foliar N linkages differed between host forest types. This result suggests that disturbance type may be a better predictor of litter and soil N responses than forest type due to similar disturbance mechanisms and disturbance legacies across both host-beetle systems.
Scheffer, Marten; Vergnon, Remi; van Nes, Egbert H; Cuppen, Jan G M; Peeters, Edwin T H M; Leijs, Remko; Nilsson, Anders N
While species fulfill many different roles in ecosystems, it has been suggested that numerous species might actually share the same function in a near neutral way. So-far, however, it is unclear whether such functional redundancy really exists. We scrutinize this question using extensive data on the world's 4168 species of diving beetles. We show that across the globe these animals have evolved towards a small number of regularly-spaced body sizes, and that locally co-existing species are either very similar in size or differ by at least 35%. Surprisingly, intermediate size differences (10-20%) are rare. As body-size strongly reflects functional aspects such as the food that these generalist predators can eat, these beetles thus form relatively distinct groups of functional look-a-likes. The striking global regularity of these patterns support the idea that a self-organizing process drives such species-rich groups to self-organize evolutionary into clusters where functional redundancy ensures resilience through an insurance effect.
Charles C. Rhoades
Full Text Available The 2010 Church’s Park Fire burned beetle-killed lodgepole pine stands in Colorado, including recently salvage-logged areas, creating a fortuitous opportunity to compare the effects of salvage logging, wildfire and the combination of logging followed by wildfire. Here, we examine tree regeneration, surface fuels, understory plants, inorganic soil nitrogen and water infiltration in uncut and logged stands, outside and inside the fire perimeter. Subalpine fir recruitment was abundant in uncut, unburned, beetle-killed stands, whereas lodgepole pine recruitment was abundant in cut stands. Logging roughly doubled woody fuel cover and halved forb and shrub cover. Wildfire consumed all conifer seedlings in uncut and cut stands and did not stimulate new conifer regeneration within four years of the fire. Aspen regeneration, in contrast, was relatively unaffected by logging or burning, alone or combined. Wildfire also drastically reduced cover of soil organic horizons, fine woody fuels, graminoids and shrubs relative to unburned, uncut areas; moreover, the compound effect of logging and wildfire was generally similar to wildfire alone. This case study documents scarce conifer regeneration but ample aspen regeneration after a wildfire that occurred in the later stage of a severe beetle outbreak. Salvage logging had mixed effects on tree regeneration, understory plant and surface cover and soil nitrogen, but neither exacerbated nor ameliorated wildfire effects on those resources.
Figueroa-Teran, Rubi; Pak, Heidi; Blomquist, Gary J; Tittiger, Claus
Ips spp. bark beetles use ipsdienol, ipsenol, ipsdienone and ipsenone as aggregation pheromone components and pheromone precursors. For Ips pini, the short-chain oxidoreductase ipsdienol dehydrogenase (IDOLDH) converts (-)-ipsdienol to ipsdienone, and thus likely plays a role in determining pheromone composition. In order to further understand the role of IDOLDH in pheromone biosynthesis, we compared IDOLDH to its nearest functionally characterized ortholog with a solved structure: human L-3-hydroxyacyl-CoA dehydrogenase type II/ amyloid-β binding alcohol dehydrogenase (hHADH II/ABAD), and conducted functional assays of recombinant IDOLDH to determine substrate and product ranges and structural characteristics. Although IDOLDH and hHADH II/ABAD had only 35% sequence identity, their predicted tertiary structures had high identity. We found IDOLDH is a functional homo-tetramer. In addition to oxidizing (-)-ipsdienol, IDOLDH readily converted racemic ipsenol to ipsenone, and stereo-specifically reduced both ketones to their corresponding (-)-alcohols. The (+)-enantiomers were never observed as products. Assays with various substrate analogs showed IDOLDH had high substrate specificity for (-)-ipsdienol, ipsenol, ipsenone and ipsdienone, supporting that IDOLDH functions as a pheromone-biosynthetic enzyme. These results suggest that different IDOLDH orthologs and or activity levels contribute to differences in Ips spp. pheromone composition. © The Authors 2016. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved.
Edburg, S. L.; Hicke, J. A.; Lawrence, D. M.; Thornton, P. E.; Meddens, A. J.
Disturbances such as land-use change, fire, and insect outbreaks play an important role in carbon cycling in forested ecosystems. In the last several decades, insect outbreaks have affected millions of hectares in the western US, similar to or greater than the area affected by fire. Bark beetles are responsible for the majority of this damage. Host trees are killed by these insects, decreasing net primary productivity (NEP) and increasing decomposition, often resulting in a net emission of carbon from the biosphere to the atmosphere. At the scale of the western US, however, this impact has not been quantified. The goal of our research is to quantify the historical impact of insect outbreaks in the western US from 1997 to 2009. We modified the NCAR Community Land Model with prognostic Carbon and Nitrogen cycling (CLM-CN) to include insect mortality. Model experiments demonstrate the sensitivity of NEP to the severity and duration of an outbreak and to the parameterization of standing dead boles and needles after an outbreak. We prescribed insect-caused tree mortality from USFS Aerial Detection Surveys for CLM-CN simulations across the western US. We find that the impact of insect outbreaks on net ecosystem productivity is 15 to 20% of that of fire during a similar time period
G. M. Abdurakhmanov
Full Text Available For the first time studied the species composition of ground beetles of coastal and island ecosystems of the Western Caspian. The article provides a comparative analysis of species composition of ground beetles and adjacent areas.
Bearup, Lindsay A.; Maxwell, Reed M.; Clow, David W.; McCray, John E.
The recent climate-exacerbated mountain pine beetle infestation in the Rocky Mountains of North America has resulted in tree death that is unprecedented in recorded history. The spatial and temporal heterogeneity inherent in insect infestation creates a complex and often unpredictable watershed response, influencing the primary storage and flow components of the hydrologic cycle. Despite the increased vulnerability of forested ecosystems under changing climate1, watershed-scale implications of interception, ground evaporation, and transpiration changes remain relatively unknown, with conflicting reports of streamflow perturbations across regions. Here, contributions to streamflow are analysed through time and space to investigate the potential for increased groundwater inputs resulting from hydrologic change after infestation. Results demonstrate that fractional late-summer groundwater contributions from impacted watersheds are 30 ± 15% greater after infestation and when compared with a neighbouring watershed that experienced earlier and less-severe attack, albeit uncertainty propagations through time and space are considerable. Water budget analysis confirms that transpiration loss resulting from beetle kill can account for the relative increase in groundwater contributions to streams, often considered the sustainable flow fraction and critical to mountain water supplies and ecosystems.
Knowles, John F.; Lestak, Leanne R.; Molotch, Noah P.
We used multiple sources of remotely sensed and ground based information to evaluate the spatiotemporal variability of snowpack accumulation, potential evapotranspiration (PET), and Normalized Difference Vegetation Index (NDVI) throughout the Southern Rocky Mountain ecoregion, USA. Relationships between these variables were used to establish baseline values of expected forest productivity given water and energy inputs. Although both the snow water equivalent (SWE) and a snow aridity index (SAI), which used SWE to normalize PET, were significant predictors of the long-term (1989-2012) NDVI, SAI explained 11% more NDVI variability than SWE. Deviations from these relationships were subsequently explored in the context of widespread forest mortality due to bark beetles. Over the entire study area, NDVI was lower per unit SAI in beetle-disturbed compared to undisturbed areas during snow-related drought; however, both SAI and NDVI were spatially heterogeneous within this domain. As a result, we selected three focus areas inside the larger study area within which to isolate the relative impacts of SAI and disturbance on NDVI using multivariate linear regression. These models explained 66%-85% of the NDVI and further suggested that both SAI and disturbance effects were significant, although the disturbance effect was generally greater. These results establish the utility of SAI as a measure of moisture limitation in snow-dominated systems and demonstrate a reduction in forest productivity due to bark beetle disturbance that is particularly evident during drought conditions resultant from low snow accumulation during the winter.
K. Handley; J. Hough-Goldstein; L.M. Hanks; J.G. Millar; V. D' amico
Cerambycid beetles are abundant and diverse in forests, but much about their host relationships and adult behavior remains unknown. Generic blends of synthetic pheromones were used as lures in traps, to assess the species richness, and phenology of cerambycids in forest fragments in northern Delaware. More than 15,000 cerambycid beetles of 69 species were trapped over...
Hoeglund, Solveig; Eklund, Karin; Bjoerkman, Christer [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Dept. of Entomology
Several species of leaf beetles (Coleoptera: Chrysomelidae) have caused economic damage in coppiced willow plantations in Britain. In Sweden we have observed outbreaks of three species; Phratora vulgatissima, Galerucella lineola and Lochmaea caprea. One feature of leaf beetles is that both adults and larvae feed on plants. The adults make holes in willow leaves when feeding whereas larvae skeletonize the leaves by eating on the leaf underside. Willows attacked by high densities of P. vulgatissima may show a yield loss of up to 40%. Leaf beetles have a large reproduction capacity. Each female can lay 10-20 eggs per day for several weeks. Without natural control the beetles would be very common in plantations. The egg and the first larval stages seem to be the most vulnerable to predation. With more knowledge about the biology of leaf beetle enemies it will perhaps be possible to use natural biological control programs as a method for managing these beetles.
Goldberg, Julia; Knapp, Michael; Emberson, Rowan M.; Townsend, J. Ian; Trewick, Steven A.
New Zealand biodiversity has often been viewed as Gondwanan in origin and age, but it is increasingly apparent from molecular studies that diversification, and in many cases origination of lineages, postdate the break-up of Gondwanaland. Relatively few studies of New Zealand animal species radiations have as yet been reported, and here we consider the species-rich genus of carabid beetles, Mecodema. Constrained stratigraphic information (emergence of the Chatham Islands) and a substitution rate for Coleoptera were separately used to calibrate Bayesian relaxed molecular clock date estimates for diversification of Mecodema. The inferred timings indicate radiation of these beetles no earlier than the mid-Miocene with most divergences being younger, dating to the Plio-Pleistocene. A shallow age for the radiation along with a complex spatial distribution of these taxa involving many instances of sympatry implicates recent ecological speciation rather than a simplistic allopatric model. This emphasises the youthful and dynamic nature of New Zealand evolution that will be further elucidated with detailed ecological and population genetic analyses. PMID:24465949
Griuntal', S Iu
Specific features of wintering of the ground beetles in three habitats (litter, soil, and bark of fallen trees and stumps) were comparatively studied in the forests of forest-steppe (Voronezh District) and subzone of broad-leaved-spruce forests (Moscow District). The main mass of ground beetles is concentrated in the upper 10-cm soil layer, irrespective of the type of watering (automorphous or hydromorphous soils). Wintering under the bark is a facultative feature of the most species occurring in these biocoenoses.
Full Text Available Analysis of the bark beetle outbreak in the forest “Alta Val Parma” (Corniglio, Parma, Italy and strategies for its regeneration. Norway spruce plantations located in the Foresta Demaniale Alta Val Parma (Corniglio, province of Parma - Italy experienced since 2004 a massive outbreak of Norway spruce bark beetle (Ips typographus. This outbreak has been triggered by the exceptionally warm and dry summer of 2003. In the following years bark beetle attacks repeated and spread, raising concern about the future of this kind of stands. A survey program has been carried out to help local administration to chose the correct managements strategies. Monitoring of Ips typographus population, carried out between 2007 and 2013, confirmed the presence of two generations per year, with values above the risk threshold in 2007 and just below though very high in 2011. In the affected area, six survey plots have been realized to test different management options with the aim of favoring a fast regeneration of the forest cover. The tested options showed the great difficulty in the establishment of natural generation either for the lack of mother plants in such pure stands or for competition with tall grasses. Sowing brought no significative results, while direct plantation of indigenous broadleaves was more effective, with almost half of the individuals still alive after three years. Our results confirm the great difficulty to rebuild the forest cover after strong ecological disturbances in these artificial forests. Hybrid management strategies and ad hoc silvicultural choices seem to be the only way to manage such kind of situations in a National park, where the priority is biodiversity conservation.
Melissa J. Fischer; Kristen M. Waring; Richard W. Hofstetter; Thomas E. Kolb
Dendroctonus adjunctus is an aggressive bark beetle species that attacks several species of pine throughout its range from southern Utah and Colorado south to Guatemala. A current outbreak of D. adjunctus provided a unique opportunity to study the relationship between this beetle and pine resin chemistry in northern Arizona. We...
Jose F. Negron; Willis C. Schaupp; Lee Pederson
There are about 500 species of bark beetles (Coleoptera: Curculionidae: Scolytinae) in the United States (Wood 1982). A number of them are important disturbance agents in forested ecosystems, occasionally creating large tracts of dead trees. One eruptive species is the Douglas-fir beetle, Dendroctonus pseudotsugae Hopkins, which utilizes Douglas-fir, Pseudotsuga...
Barbara J. Bentz; Jacob P. Duncan; James A. Powell
Future forests are being shaped by changing climate and disturbances. Climate change is causing large-scale forest declines globally, in addition to distributional shifts of many tree species. Because environmental cues dictate insect seasonality and population success, climate change is also influencing tree-killing bark beetles. The mountain pine beetle,...
Barbara J. Bentz; Greta Schen-Langenheim
The mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae, Scolytinae) (MPB), is a bark beetle native to western North American forests, spanning wide latitudinal and elevational gradients. MPB infest and reproduce within the phloem of most Pinus species from northern Baja California in Mexico to central British Columbia in...
Knowles, J. F.; Lestak, L.; Molotch, N. P.
We evaluated the long term (1989-2012) relationship between the satellite-observed Normalized Difference Vegetation Index (NDVI), snowpack accumulation, and atmospheric demand throughout the Southern Rocky Mountain Ecoregion, USA. Deviations from this relationship were further explored during pre- and post-disturbance conditions associated with bark beetles and drought. Over the entire study area, both the snow water equivalent (SWE) and a snow aridity index (SAI), which used the SWE to normalize potential evapotranspiration (PET), were significant predictors of the long-term AVHRR NDVI, but the SAI was a better predictor of NDVI relative to SWE regardless of disturbance. Since these relationships were weaker in disturbed areas, we also introduced a metric of tree mortality, and subsequent multiple linear regression of SAI and cumulative mortality best predicted the NDVI from a pair of heavily impacted focus areas within the larger study area. The post-disturbance NDVI was systematically reduced per unit SAI in these areas, and the difference between the observed and predicted (from pre-disturbance regressions) post-disturbance NDVI was significantly correlated with the cumulative forest mortality. At the Ecoregion scale, these disturbance effects were not clearly evident, and we attribute this to spatial variability of both SAI and NDVI throughout the large study area as evidenced by spatial analysis of Moderate Resolution Imaging Spectroradiometer (MODIS)-derived data. These results constrain the expected reduction in forest productivity due to disturbance and demonstrate that this reduction can be particularly evident during drought conditions resultant from low snow accumulation during the winter. Hence, terrestrial carbon uptake may decrease non-linearly post disturbance. This work has implications for predicting the ecohydrological response to climate change in the southern Rocky Mountains, as reductions in SWE and increases in PET are predicted for this area
Sharon J. Martinson; Tiina Ylioja; Brian T. Sullivan; Ronald F. Billings; Matthew P. Ayres
Among the most striking changes in ecosystems are those that happen abruptly and resist return to the original condition (i.e., regime shifts). This frequently involves conspicuous changes in the abundance of one species (e.g., an outbreaking pest or keystone species). Alternate attractors in population dynamics could explain switches between low and high levels of...
Benjamin C. Bright
Full Text Available Wildfire behavior depends on the type, quantity, and condition of fuels, and the effect that bark beetle outbreaks have on fuels is a topic of current research and debate. Remote sensing can provide estimates of fuels across landscapes, although few studies have estimated surface fuels from remote sensing data. Here we predicted and mapped field-measured canopy and surface fuels from light detection and ranging (lidar and Landsat time series explanatory variables via random forest (RF modeling across a coniferous montane forest in Colorado, USA, which was affected by mountain pine beetles (Dendroctonus ponderosae Hopkins approximately six years prior. We examined relationships between mapped fuels and the severity of tree mortality with correlation tests. RF models explained 59%, 48%, 35%, and 70% of the variation in available canopy fuel, canopy bulk density, canopy base height, and canopy height, respectively (percent root-mean-square error (%RMSE = 12–54%. Surface fuels were predicted less accurately, with models explaining 24%, 28%, 32%, and 30% of the variation in litter and duff, 1 to 100-h, 1000-h, and total surface fuels, respectively (%RMSE = 37–98%. Fuel metrics were negatively correlated with the severity of tree mortality, except canopy base height, which increased with greater tree mortality. Our results showed how bark beetle-caused tree mortality significantly reduced canopy fuels in our study area. We demonstrated that lidar and Landsat time series data contain substantial information about canopy and surface fuels and can be used for large-scale efforts to monitor and map fuel loads for fire behavior modeling at a landscape scale.
Bright, Benjamin C.; Hudak, Andrew T.; Meddens, Arjan J.H.; Hawbaker, Todd J.; Briggs, Jenny S.; Kennedy, Robert E.
Wildfire behavior depends on the type, quantity, and condition of fuels, and the effect that bark beetle outbreaks have on fuels is a topic of current research and debate. Remote sensing can provide estimates of fuels across landscapes, although few studies have estimated surface fuels from remote sensing data. Here we predicted and mapped field-measured canopy and surface fuels from light detection and ranging (lidar) and Landsat time series explanatory variables via random forest (RF) modeling across a coniferous montane forest in Colorado, USA, which was affected by mountain pine beetles (Dendroctonus ponderosae Hopkins) approximately six years prior. We examined relationships between mapped fuels and the severity of tree mortality with correlation tests. RF models explained 59%, 48%, 35%, and 70% of the variation in available canopy fuel, canopy bulk density, canopy base height, and canopy height, respectively (percent root-mean-square error (%RMSE) = 12–54%). Surface fuels were predicted less accurately, with models explaining 24%, 28%, 32%, and 30% of the variation in litter and duff, 1 to 100-h, 1000-h, and total surface fuels, respectively (%RMSE = 37–98%). Fuel metrics were negatively correlated with the severity of tree mortality, except canopy base height, which increased with greater tree mortality. Our results showed how bark beetle-caused tree mortality significantly reduced canopy fuels in our study area. We demonstrated that lidar and Landsat time series data contain substantial information about canopy and surface fuels and can be used for large-scale efforts to monitor and map fuel loads for fire behavior modeling at a landscape scale.
Melissa J. Fischer; Kristen M. Waring; Richard W. Hofstetter; Thomas E. Kolb
Dendroctonus adjunctus is an aggressive bark beetle species that attacks several species of pine throughout its range from southern Utah and Colorado south to Guatemala. A current outbreak of D. adjunctus provided a unique opportunity to study the relationship between this beetle and pine resin chemistry in northern Arizona. We compared the resin composition of trees...
Sharp, J.; Bokman, C.; Brouillard, B.; Mikkelson, K. M.
Recent increases in the magnitude and occurrence of bark beetle-induced tree mortality are disrupting evergreen forests globally. To better understand how these perturbed ecosystems respond, we investigated whether the extent of local tree mortality is an important parameter to predict terrestrial biogeochemical and microbial responses in lodgepole pines (Pinus contorta) infested by mountain pine beetles in the Colorado Rocky Mountains. Soil biogeochemical parameters within three near-surface soil horizons were compared between healthy and deceased trees surrounded by varying extents of tree mortality in order to isolate the effects of surrounding tree mortality on carbon and nitrogen cycling. Results revealed that C:N ratios decreased as surrounding tree mortality increased in the upper soil litter and organic horizons. A threshold response was found for ammonium in these layers, which accumulated only under trees surrounded by at least 40% tree mortality. Concurrently, the extent of tree mortality and the C:N ratio also affected the soil microbial community structure and function. Bacterial clades specific to nitrogen cycling and exoenzyme activity were more strongly related to changes in C:N ratio than surrounding tree mortality. Alpha diversity within the bacterial soil community increased and beta diversity clustered in accordance with more extensive surrounding tree mortality. These biogeochemical and microbial indicators suggest that high degrees of beetle-induced mortality may be shifting the terrestrial environment of Rocky Mountain lodgepole pine forests from an N-limited ecosystem to one where N is in excess with implications for forest recovery and nitrogen export.
Thomas L. Eberhardt; Joseph Dahlen; Laurence Schimleck
Composition of the southern pine forest is now predominated by two species, loblolly pine (Pinus taeda L.) and slash pine (Pinus elliottii Engelm.), owing to fire suppression activities, natural regeneration on abandoned agricultural lands, and extensive planting. Comparison of the wood and bark physical properties of these...
Min Lu; Michael J. Wingfield; Nancy E. Gillette; Sylvia R. Mori; Jian-Hua Sun
Recent studies have investigated the relationships between pairs or groups of exotic species to illustrate invasive mechanisms, but most have focused on interactions at a single trophic level.Here, we conducted pathogenicity tests, analyses of host volatiles and fungal growth tests to elucidate an intricate network of interactions between the host...
Chris Schnepf; Russell T. Graham; Sandy Kegley; Theresa B. Jain
Forest organic debris includes tree limbs, boles (trunks), needles, leaves, snags, and other dead organic materials. It ranges in amount and composition depending on a forest's history, tree species, condition, and age. In the Inland Northwest (Idaho, western Montana, eastern Oregon, and eastern Washington) there is a lot of discussion and concern about removing...
Miguel A. Anducho-Reyes; Anthony I. Cognato; Jane L. Hayes; Gerardo. Zuniga
Dendroctonus mexicanus is polyphagous within the Pinus genus and has a wide geographical distribution in Mexico and Guatemala. We examined the pattern of genetic variation across the range of this species to explore its demographic history and its phylogeographic pattern. Analysis of the mtDNA sequences of 173 individuals from...
Jenny C. Staeben; Brian Sullivan; John T. Nowak; Kamal J.K. Gandhi
Multi-trophic interactions between pine bark beetles, their host trees, and predators are mediated in part by volatile terpenes in host tree oleoresin that can influence aggregation and/or host finding by both prey and predator species. The southern pine beetle, Dendroctonus frontalis Zimmermann, mass-attacks pine trees in response to its aggregation pheromone combined...
Abigail J. Walter; Stephen A. Kells; Robert C. Venette; Steven J. Seybold
When invasive herbivorous insects encounter novel plant species, they must determine whether the novel plants are hosts. The Mediterranean pine engraver, Orthotomicus erosus (Wollaston), an exotic bark beetle poised to expand its range in North America, accepts hosts after contacting the bark. To test the hypothesis that O. erosus...
Ajay Kumar Singh Rawat
Full Text Available Objective: To evaluate the pharmacognostical comparison (Botanical study, physicochemical parameters, HPTLC analysis in stem barks of four Ficus species (family-Moraceae viz. F. religiosa L, F. glomerata Roxb, F. retusa auct. & F. carica. Methods: Estimation of Phytochemical markers viz: 毬 -sitosterol and lupeol was quantified by HPTLC method and antioxidant studies by carried by DPPH method. Results: HPTLC method showed considerable amount of variation with two reference standard viz: 毬 -sitosterol and lupeol content in stem bark of F. religiosa, F. glomerata, F. retusa & F. carica and it were found 0.084, 0.041, 0.059 & 0.131 and 0.020, 0.043, 0.069 & 0.049 respectively. The antioxidant potential of ethanolic extract of stem bark of F. religiosa, F. retusa, F. glomerata & F. carica were found 46.86%, 42.56%, 31.25% & 25.63% at 0.1mg/ mL concentration. Conclusion: The present work was taken up with a view to lay down standards which will contribute significantly to quality control of these medicinally useful Ficus species. It also provides suitable criteria to differentiate the stem barks of four Ficus species.
Wesley G. Page; Martin E. Alexander; Michael J. Jenkins
Large wildland fires in conifer forests typically involve some degree of crowning, with their initiation and propagation dependent upon several characteristics of the canopy fuels. Recent outbreaks of mountain pine beetle (Dendroctonus ponderosae Hopkins) in lodgepole pine (Pinus contorta Dougl. var. latifolia E ngelm.) forests and spruce beetle (Dendroctonus...
Serrano, Artur R M; Capela, Rúben A; Oesterle, Andreas
Three new species of tiger beetles, two of the genus Trichotaenia Rivalier, 1957 and one of the genus Cylindera Westwood, 1831, subgenus Ifasina Jeannel, 1946 are described from Angola. An annotated list of species of Cicindelina sampled in this country is provided also. Records for three species previously unknow from Angola are given: Ophryodera smrzi Werner, 2005, Lophyra clatharta (Dejean, 1825) and Lophyra sumlini Cassola, 1976. Some considerations on the distribution and general ecology of these beetles in Angola are also presented. Further, two dichotomic keys are made available for the identification of Trichotaenia species with marked shoulders and Cylindera (Ifasina) species of western and southwestern Africa, respectively.
Bergmann, David J; Brandenburg, Dylan; Petit, Samantha; Gabel, Mark
Ground beetles (Coleoptera: Carabidae) are a major component of terrestrial invertebrate communities and have been used as bioindicators of habitat change and disturbance. The Black Hills of South Dakota is a small area with a high biodiversity, but the ground beetles of this region are little studied. The habitat preferences of ground beetles in the Black Hills are unknown, and baseline data must be collected if these beetles are to be used in the future as bioindicators. Ground beetles (Coleoptera: Carabidae) were collected from pitfall traps at two sites in each of five kinds of habitats (grassland, bur oak-ironwood forests, ponderosa pine-common juniper forests, aspen-pine forests, and a spruce forest) from which habitat structure characteristics and plant abundance data also were collected. In total, 27 species of ground beetles were identified. Although some species, such as Dicaelus sculptilis Say were found in most habitats, other species showed distinct habitat preferences: Poecilus lucublandus (Say) preferred oak forests, Pasimachus elongatus LeConte preferred grasslands, and Calathus ingratus Dejean preferred high-elevation aspen-pine forests. Pterostichus adstrictus Escholtz was found only in woodlands, and Carabus taedatus Say strictly in higher elevation (over 1,500 m) aspen or coniferous woods, and may represent relict populations of boreal species. Elevation, exposure to sunlight, and cover of woody plants strongly influence the structure of carabid communities in the Black Hills.
Cobb, F.W. Jr.; Wood, D.L.; Stark, R.W.; Miller, P.R.
Studies were made during the summer, 1966, to determine the effects of air pollution injury (i.e., chlorotic decline) of ponderosa pine on various factors related to tree physiology. The results of these studies show that disease caused by photochemical atmospheric pollution affects certain physiological properties of ponderosa pine that may be related to increased susceptibility to bark beetles. Oleoresin exudation pressure, yield, and rate of flow were substantially reduced in severely affected trees, but crystallization of resin increased as the severity of the disease became greater. Both sapwood and phloem moisture contents were less in diseased trees. Phloem thickness in advanced-diseased trees was less than 60% of that in healthy trees.
Olive trees protected from the olive bark beetle, Phloeotribus scarabaeoides (Bernard 1788) (Coleoptera, Curculionidae, Scolytinae) with a pyrethroid insecticide: Effect on the insect community of the olive grove.
Ruano, Francisca; Campos, Mercedes; Sánchez-Raya, A Juan; Peña, Aránzazu
Field studies were performed in two successive years, 2005 and 2006, in different olive groves of the province of Granada (South-eastern Spain) by spraying olive trees (Olea europaea) with a pyrethroid insecticide, deltamethrin, for the control of the olive bark beetle Phloeotribus scarabaeoides (Bernard 1788) (Coleoptera, Curculionidae, Scolytinae). Three olive groves received each year three treatments in June consisting of water (control) and two insecticide doses, which were halved the second year. From June to September six olives trees per site were inspected every 15d for feeding galleries in olive branches; the arthropods, collected in traps placed below the olive trees (three traps per site), were identified and counted. Results show that feeding galleries were significantly reduced, what proves that the pyrethroid insecticide efficiently protected the olive trees from the olive bark beetle with a single application and even at the lower dose employed in 2006. Some repellent effect may occur as deduced from the number of P. scarabaeoides individuals captured. Other individuals from the insect community were also affected to a great extent by insecticide application, though no statistical differences were found among the treatments due to the high variability in insect captures. Among the parasitoids, Scelionidae, Encyrtidae, Eurytomidae and Pteromalidae were captured in great numbers. Mirids were the predators whose numbers drastically increased in traps placed under the treated trees, while spiders and ants were less affected. A knock-down effect was noticed for some insect groups, for instance mirids and Euphyllura olivina. Approximately 80% of their captures corresponded to the first date of sampling after insecticide application. 2010 Elsevier Ltd. All rights reserved.
Huang, Y.T.; Kolařík, Miroslav; Kasson, M.T.; Hulcr, J.
Roč. 109, č. 5 (2017) ISSN 0027-5514 Institutional support: RVO:61388971 Keywords : Bionectriaceae * ectosymbiont * North America Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 2.550, year: 2016
Stoyanova Marina; Kandilarov Alexander; Koutev Vesselin; Nitcheva Olga; Dobreva Polya
Much of the coniferous forest in Bulgaria is struck by Ips typographus, Ips acuminatus and Ips sexdentatus beetles. The multispectral camera test near the town of Kalofer, Bulgaria in August 2017, showed the good capabilities of remote-piloted aircraft for observation and mapping of large areas in highly intersected areas. The collected data from the multispectral camera allowed producing maps with different indices of the observed vegetation. Beetles damaged stains were identified and outlin...
The Asian longhorned beetle (Anoplophora glabripennis; AGLAB) is a globally significant invasive species capable of inflicting severe feeding damage on many important orchard, ornamental and forest trees. Genome sequencing, annotation, gene expression assays, and functional and comparative genomic s...
Bianchi, Sauro; Kroslakova, Ivana; Janzon, Ron; Mayer, Ingo; Saake, Bodo; Pichelin, Frédéric
Condensed tannins extracted from European softwood bark are recognized as alternatives to synthetic phenolics. The extraction is generally performed in hot water, leading to simultaneous extraction of other bark constituents such as carbohydrates, phenolic monomers and salts. Characterization of the extract's composition and identification of the extracted tannins' molecular structure are needed to better identify potential applications. Bark from Silver fir (Abies alba [Mill.]), European larch (Larix decidua [Mill.]), Norway spruce (Picea abies [Karst.]), Douglas fir (Pseudotsuga menziesii [Mirb.]) and Scots pine (Pinus sylvestris [L.]) were extracted in water at 60°C. The amounts of phenolic monomers, condensed tannins, carbohydrates, and inorganic compounds in the extract were determined. The molecular structures of condensed tannins and carbohydrates were also investigated (HPLC-UV combined with thiolysis, MALDI-TOF mass spectrometry, anion exchange chromatography). Distinct extract compositions and tannin structures were found in each of the analysed species. Procyanidins were the most ubiquitous tannins. The presence of phenolic glucosides in the tannin oligomers was suggested. Polysaccharides such as arabinans, arabinogalactans and glucans represented an important fraction of all extracts. Compared to traditionally used species (Mimosa and Quebracho) higher viscosities as well as faster chemical reactivities are expected in the analysed species. The most promising species for a bark tannin extraction was found to be larch, while the least encouraging results were detected in pine. A better knowledge of the interaction between the various extracted compounds is deemed an important matter for investigation in the context of industrial applications of such extracts. Copyright © 2015 Elsevier Ltd. All rights reserved.
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.
Dodds, Kevin J; Miller, Daniel R
Sirex noctilio 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. noctilio 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. pini 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.
Jordal Bjarte H
Full Text Available Abstract Background Fungus farming is an unusual life style in insects that has evolved many times in the wood boring weevils named ‘ambrosia beetles’. Multiple occurrences of this behaviour allow for a detailed comparison of the different origins of fungus farming through time, its directionality, and possible ancestral states. We tested these hypotheses with a phylogeny representing the largest data set to date, nearly 4 kb of nucleotides from COI, EF-1α, CAD, ArgK, 28S, and 200 scolytine taxa. Results Phylogenetic analyses using Bayesian or parsimony approaches placed the root of Scolytinae close to the tribe Scolytini and Microborus, but otherwise indicated low resolution at older nodes. More recent clades were well resolved, including ten origins of fungus farming. There were no subsequent reversals to bark or phloem feeding in the fungus farming clades. The oldest origin of fungus farming was estimated near 50 Ma, long after the origin of Scolytinae (100-120 Ma. Younger origins included the species rich Xyleborini, dated to 21 Ma. Sister group comparisons and test of independence between traits indicated that neither gregarious larval feeding nor regular inbreeding by sibling mating was strongly correlated with the origin of fungus farming. Conclusion Origins of fungus farming corresponded mainly with two periods of global warming in the Cenozoic era, which were characterised by broadly distributed tropical forests. Hence, it seems likely that warm climates and expanding tropical angiosperm forests played critical roles in the successful radiation of diverse fungus farming groups. However, further investigation will likely reveal additional biological factors that promote fungus farming.
Donald E. Hilt; Everette D. Rast; Herman J. Bailey
General models for predicting DIB/DOB ratios up the stem, applicable over wide geographic areas, have been developed for 10 important hardwood species. Results indicate that the ratios either decrease or remain constant up the stem. Methods for adjusting the general models to local conditions are presented. The prediction models can be used in conjunction with optical...
Diepenbrock, Lauren M; Fothergill, Kent; Tindall, Kelly V; Losey, John E; Smyth, Rebecca R; Finke, Deborah L
The diversity and abundance of native lady beetles (Coccinellidae) in North America has declined in recent decades. This decline is often correlated with the introduction and establishment of exotic lady beetle species, including Coccinella septempunctata L. and Harmonia axyridis Pallas, suggesting that exotic species precipitated the decline of native lady beetles. We examined species records of native coccinellids in Missouri over 118 yr and asked whether the species composition of the community experienced a shift following the establishment of the exotic species. We found that the contemporary native coccinellid community is different from the community that was present nearly a century ago. However, there was no evidence for a recent abrupt shift in composition triggered by the establishment of exotic species. Instead, our data suggest that the native lady beetle community has been undergoing consistent and gradual change over time, with some species decreasing in abundance and others increasing. While not excluding exotic species as a factor contributing to the decline of native lady beetle species, our findings suggest that other continuous factors, like land use change, may have played a more influential role in determining the composition of the native coccinellid communities within our region. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: firstname.lastname@example.org.
Stork, Nigel E; McBroom, James; Gely, Claire; Hamilton, Andrew J
It has been suggested that we do not know within an order of magnitude the number of all species on Earth [May RM (1988) Science 241(4872):1441-1449]. Roughly 1.5 million valid species of all organisms have been named and described [Costello MJ, Wilson S, Houlding B (2012) Syst Biol 61(5):871-883]. Given Kingdom Animalia numerically dominates this list and virtually all terrestrial vertebrates have been described, the question of how many terrestrial species exist is all but reduced to one of how many arthropod species there are. With beetles alone accounting for about 40% of all described arthropod species, the truly pertinent question is how many beetle species exist. Here we present four new and independent estimates of beetle species richness, which produce a mean estimate of 1.5 million beetle species. We argue that the surprisingly narrow range (0.9-2.1 million) of these four autonomous estimates--derived from host-specificity relationships, ratios with other taxa, plant:beetle ratios, and a completely novel body-size approach--represents a major advance in honing in on the richness of this most significant taxon, and is thus of considerable importance to the debate on how many species exist. Using analogous approaches, we also produce independent estimates for all insects, mean: 5.5 million species (range 2.6-7.8 million), and for terrestrial arthropods, mean: 6.8 million species (range 5.9-7.8 million), which suggest that estimates for the world's insects and their relatives are narrowing considerably.
Full Text Available The mycobiota of the beetles of the phloem-feeding spruce bark beetle, Ips typographus was studied. The most important group of fungi were the ophiostomatoid fungi. Among them O. penicillatum was very frequent ophiostomatoid species. Other common fungi were O. ainoae, O. bicolor, O. piceaperdum and O. piceae. The ophiostomatoid fungi were often more frequent in beetles collected in galleries than in the beetles caught With a trap. Generally the ophiostomatoid fungi were more ofien isolated from the beetle.s bathed in sterile water for 30 seconds. However C. polonica, O. ainoae, and O. minutum occurred most abundantly in the beetles disinfected in 96% ethyl alcohol for 15 and 30 seconds.
Spier, L. [Alterra, Landscape Center, POB 47, 6700 AA Wageningen (Netherlands); Dobben, H. van, E-mail: email@example.com [Alterra, Landscape Center, POB 47, 6700 AA Wageningen (Netherlands); Dort, K. van [Alterra, Landscape Center, POB 47, 6700 AA Wageningen (Netherlands)
To study the pH preference of epiphytic lichens, the bark pH of Fraxinus, Tilia, Quercus and Ulmus trees in an urban environment was measured using a flat surface electrode. The total number of trees was 253. A survey was made of the lichens in a 40 x 40 cm quadrat surrounding the pH measurement point. Our data analysis using multivariate and univariate statistical techniques indicates that the tree species is the most important factor influencing lichen colonisation, and that bark pH alone is of less importance. We hypothesize that the changed pollution climate, with strong decreases in both sulphur dioxide and ammonia concentrations over the past two decades and a concomitant general increase in bark pH, has made epiphytes less sensitive to pH. - Tree species, rather than bark pH determines the occurrence of acidophytes and nitrophytes on trees.
Kim, E. S. M.; Ballantyne, A. P.; Cooper, L. A.; Hursh, A.
Global climate change has had extensive impacts on the forest ecosystems of the western US, namely by causing increases in mountain pine beetle numbers and wildfires. Mountain pine beetles experience higher survival rates due to milder winters, allowing for greater frequency and severity of attacks and in turn causing more widespread pine tree mortality. Meanwhile, the arid conditions created by this temperature increase have been conducive to a surge in wildfires. Although many investigations have been carried out on the soil biogeochemistry in areas hit by one or the other, no study to our knowledge has explicitly researched the compound effects of these disturbances. This study examined soil levels of carbon (C) and nitrogen (N) as well as the C/N ratios of pine and fir soil communities that have been affected by both beetle and fire disturbance. Our results show that no significant differences were found in the C/N ratios in response to all modes of disturbance. However, significant C losses from the O horizon, but not the M horizon, were observed following wildfire. Similarly, losses in N from just the O horizon were observed, but these were not significant. In conclusion, fire resulted in marked declines in soil C, and forests impacted by beetle infestation and fire experienced C losses similar to fire alone.
Byron J. Collins; Charles C. Rhoades; Robert M. Hubbard; Michael A. Battaglia
In the southern Rocky Mountains, current mountain pine beetle (Dendroctonus ponderosae Hopkins) outbreaks and associated harvesting have set millions of hectares of lodgepole pine (Pinus contorta var. latifolia Engelm. ex Wats.) forest onto new stand development trajectories. Information about immediate, post-disturbance tree regeneration will provide insight on...
Santaharju, J.; Helminen, S.-L.; Yrjoelae, R. (Environmental Research Yrjoelae Ltd, Helsinki (Finland))
The species of ants and Ground beetles at Olkiluoto in Eurajoki were studied in the summer of 2008 during two trapping periods: in June and August. The research goal was to clarify the species on Olkiluoto island of the earlier mentioned groups, at least at the family level, and to collect samples for further examination by Posiva. The trapping areas were selected at Olkiluoto in Posiva test monitoring sectors, a part of the trapping areas was the same as the earlier study. Species of ants, depending on their particular species, are a very dominating group of insects. The ants are the most important predators, scavengers and soil movers in Finnish forests. It looks as if the biomass of ants may be more than 10% of the biomass of all animals in certain areas of Finnish forests. In Finland there are about 60 species of ants that have been observed. They have been divided into four sub-groups, which are Myrmicinae, Formicinae, Ponerinae and Dolichoderinae. In Finland there are close to 300 species of ground beetles (Carabidae), which are divided into dozens of different families. The species, to a great extent, consist mostly of predatory insects that prey on microbes in field layers, but a part of them are specialized in feeding on flora. Ground beetles are usually divided into three groups according to their choice of habitat: Species that favour open biotopes, species that favour forests, and generalist species that can thrive in a variety of environments. Ground beetles also reflect changes in their living environment, and possibly they can be significant as socalled bio-indicators. Pitfall traps were used as the method of research. The preservative fluid used was ethanol (50%) with dishwashing liquid to remove surface tension. The points were located in various different biotopes in fields, meadows and forests. The data collected was defined as a minimum for the family level of Ground beetles and for ants to the species or species pairs. The species of Ground
Santaharju, J.; Helminen, S.-L.; Yrjoelae, R.
The species of ants and Ground beetles at Olkiluoto in Eurajoki were studied in the summer of 2008 during two trapping periods: in June and August. The research goal was to clarify the species on Olkiluoto island of the earlier mentioned groups, at least at the family level, and to collect samples for further examination by Posiva. The trapping areas were selected at Olkiluoto in Posiva test monitoring sectors, a part of the trapping areas was the same as the earlier study. Species of ants, depending on their particular species, are a very dominating group of insects. The ants are the most important predators, scavengers and soil movers in Finnish forests. It looks as if the biomass of ants may be more than 10% of the biomass of all animals in certain areas of Finnish forests. In Finland there are about 60 species of ants that have been observed. They have been divided into four sub-groups, which are Myrmicinae, Formicinae, Ponerinae and Dolichoderinae. In Finland there are close to 300 species of ground beetles (Carabidae), which are divided into dozens of different families. The species, to a great extent, consist mostly of predatory insects that prey on microbes in field layers, but a part of them are specialized in feeding on flora. Ground beetles are usually divided into three groups according to their choice of habitat: Species that favour open biotopes, species that favour forests, and generalist species that can thrive in a variety of environments. Ground beetles also reflect changes in their living environment, and possibly they can be significant as socalled bio-indicators. Pitfall traps were used as the method of research. The preservative fluid used was ethanol (50%) with dishwashing liquid to remove surface tension. The points were located in various different biotopes in fields, meadows and forests. The data collected was defined as a minimum for the family level of Ground beetles and for ants to the species or species pairs. The species of Ground
Miriam F. Cooperband
Full Text Available Three cryptic species in the Euwallacea fornicatus species complex were reared in laboratory colonies and investigated for the presence of pheromones. Collections of volatiles from combinations of diet, fungus, beetles, and galleries from polyphagous shot hole borer (Euwallacea sp. #1 revealed the presence of 2-heneicosanone and 2-tricosanone only in the presence of beetles, regardless of sex. Subsequent examination of volatiles from the other two species, tea shot hole borer (Euwallacea sp. #2 and Kuroshio shot hole borer (Euwallacea sp. #5, revealed these two ketones were present in all three species but in different ratios. In dual choice olfactometer behavioral bioassays, mature mated females were strongly attracted to a synthetic binary blend of ketones matching their own natural ratios. However, females in each species were repelled by ketone blends in ratios corresponding to the other two species. Males of each species responded similarly to females when presented with ratios matching their own or the other two species. The presence of these compounds in the three beetle species, in ratios unique to each species, and their strong species-specific attraction and repellency, suggests they are pheromones. The ecological function of these pheromones is discussed. In addition to the pheromones, the previously known attractant (1S,4R-p-menth-2-en-1-ol (also known as quercivorol was discovered in the presence of the fungal symbionts, but not in association with the beetles. Quercivorol was tested in a dual-choice olfactometer and was strongly attractive to all three species. This evidence suggests quercivorol functions as a kairomone for members of the E. fornicatus species complex, likely produced by the symbiotic fungi.
Jennifer L Kovacs
Full Text Available Heritable symbionts have been found to mediate interactions between host species and their natural enemies in a variety of organisms. Aphids, their facultative symbionts, and their potential fitness effects have been particularly well-studied. For example, the aphid facultative symbiont Regiella can protect its host from infection from a fungal pathogen, and aphids with Hamiltonella are less likely to be parasitized by parasitic wasps. Recent work has also found there to be negative fitness effects for the larvae of two species of aphidophagous lady beetles that consumed aphids with facultative symbionts. In both species, larvae that consumed aphids with secondary symbionts were significantly less likely to survive to adulthood. In this study we tested whether adult Harmonia axyridis and Hippodamia convergens lady beetles avoided aphids with symbionts in a series of choice experiments. Adults of both lady beetle species were as likely to choose aphids with symbionts as those without, despite the potential negative fitness effects associated with consuming aphids with facultative symbionts. This may suggest that under natural conditions aphid secondary symbionts are not a significant source of selection for predatory lady beetles.
Wolf, Candice; Voisin, Dené; Wolf, Seth
Heritable symbionts have been found to mediate interactions between host species and their natural enemies in a variety of organisms. Aphids, their facultative symbionts, and their potential fitness effects have been particularly well-studied. For example, the aphid facultative symbiont Regiella can protect its host from infection from a fungal pathogen, and aphids with Hamiltonella are less likely to be parasitized by parasitic wasps. Recent work has also found there to be negative fitness effects for the larvae of two species of aphidophagous lady beetles that consumed aphids with facultative symbionts. In both species, larvae that consumed aphids with secondary symbionts were significantly less likely to survive to adulthood. In this study we tested whether adult Harmonia axyridis and Hippodamia convergens lady beetles avoided aphids with symbionts in a series of choice experiments. Adults of both lady beetle species were as likely to choose aphids with symbionts as those without, despite the potential negative fitness effects associated with consuming aphids with facultative symbionts. This may suggest that under natural conditions aphid secondary symbionts are not a significant source of selection for predatory lady beetles. PMID:28880922
Kovacs, Jennifer L; Wolf, Candice; Voisin, Dené; Wolf, Seth
Heritable symbionts have been found to mediate interactions between host species and their natural enemies in a variety of organisms. Aphids, their facultative symbionts, and their potential fitness effects have been particularly well-studied. For example, the aphid facultative symbiont Regiella can protect its host from infection from a fungal pathogen, and aphids with Hamiltonella are less likely to be parasitized by parasitic wasps. Recent work has also found there to be negative fitness effects for the larvae of two species of aphidophagous lady beetles that consumed aphids with facultative symbionts. In both species, larvae that consumed aphids with secondary symbionts were significantly less likely to survive to adulthood. In this study we tested whether adult Harmonia axyridis and Hippodamia convergens lady beetles avoided aphids with symbionts in a series of choice experiments. Adults of both lady beetle species were as likely to choose aphids with symbionts as those without, despite the potential negative fitness effects associated with consuming aphids with facultative symbionts. This may suggest that under natural conditions aphid secondary symbionts are not a significant source of selection for predatory lady beetles.
du Toit, C. A.; Holter, P.; Lutermann, H.
Various species of dung beetle serve as intermediate hosts after ingesting the embryonated eggs (1115 x 3037 mu m) of Spirocerca lupi (Spirurida: Spirocercidae) in dog faeces. The feeding mechanisms of coprophagous dung beetles restrict the size of the food particles they can ingest and hence may...
Westbrook, Jared W; Resende, Marcio F R; Munoz, Patricio; Walker, Alejandro R; Wegrzyn, Jill L; Nelson, C Dana; Neale, David B; Kirst, Matias; Huber, Dudley A; Gezan, Salvador A; Peter, Gary F; Davis, John M
Rapidly enhancing oleoresin production in conifer stems through genomic selection and genetic engineering may increase resistance to bark beetles and terpenoid yield for liquid biofuels. We integrated association genetic and genomic prediction analyses of oleoresin flow (g 24 h(-1)) using 4854 single nucleotide polymorphisms (SNPs) in expressed genes within a pedigreed population of loblolly pine (Pinus taeda) that was clonally replicated at three sites in the southeastern United States. Additive genetic variation in oleoresin flow (h(2) ≈ 0.12-0.30) was strongly correlated between years in which precipitation varied (r(a) ≈ 0.95), while the genetic correlation between sites declined from 0.8 to 0.37 with increasing differences in soil and climate among sites. A total of 231 SNPs were significantly associated with oleoresin flow, of which 81% were specific to individual sites. SNPs in sequences similar to ethylene signaling proteins, ABC transporters, and diterpenoid hydroxylases were associated with oleoresin flow across sites. Despite this complex genetic architecture, we developed a genomic prediction model to accelerate breeding for enhanced oleoresin flow that is robust to environmental variation. Results imply that breeding could increase oleoresin flow 1.5- to 2.4-fold in one generation. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.
Full Text Available This research determine the total phenol and flavonoids content as well as the fungistatic activity of hot water wood sawdust and bark extracts on Coniophora puteana and Trametes versicolor. Extracts tested were taken from Condalia hookeri M.C. Johnst., Ebenopsis ebano (Berl. Britton et Rose, Helietta parvifolia (Gray Benth, Leucaena leucocephala (Lam. de Wit, and Prosopis laevigata (Humb. et Bonpl. ex Willd. The extraction was developed with soxhlet aparats, phenol concentration was determined with Folin-Ciocalteu method and flavonoide was determined by Heimler procedure. Phenol concentration ranged between 50Â±11 to 827Â±23 mg g-1 and flavonoids content between 15Â±2 to 708Â±30 mg g-1. All extracts tested inhibited growth of the fungal species. The highest inhibition effect (88%Â±1 occurred on C. puteana with L. leucocephala wood sawdust extracts at 2 mg ml-1, this species also reduced the growth on T. versicolor by 75%Â±12 when used at 10 mg ml-1, wood sawdust extracts of H. parvifolia and C. hookerii at same concentration reduced the growth of T. versicolor in 43%Â±3 and 40%Â±4 respectively. Inhibition of bark extracts of E. ebano was 84Â±5 and 80Â±7 % for H. parvifolia. A negative relationship between growing inhibitory activity and the content of total phenolics in the extracts was obtained.
Holliday, Alison E; Walker, Faye M; Brodie, Edmund D; Formica, Vincent A
Forked fungus beetles, Bolitotherus cornutus, feed, mate, and live on the brackets of several species of shelf fungus that grow on decaying logs. In response to the specific threat stimulus of mammalian breath, B. cornutus beetles produce a volatile defensive secretion. We tested beetles collected from different host fungi to determine whether defensive secretion blends varied with host type. Using solid phase microextraction and gas chromatography-mass spectrometry, we detected large amounts of the alkylated benzoquinones, methyl-p-benzoquinone (toluquinone) and ethyl-p-benzoquinone, and smaller quantities of p-benzoquinone, 3-methylphenol (m-cresol), 3-ethylphenol, 2-methylhydroquinone, and 2-ethylhydroquinone in secretions. Volatile composition did not differ between male and female beetles. Secretions did differ between beetles collected from two species of fungus, Ganoderma applanatum and Fomes fomentarius, with the relative amount of p-benzoquinone secreted being the most important factor. Other relationships among the volatile components are discussed.
Zúñiga, Beatriz; Guevara-Fefer, Patricia; Herrera, Josefina; Contreras, José Luis; Velasco, Luis; Pérez, Francisco Javier; Esquivel, Baldomero
The volatile fractions from the bark of eight species of Mexican Bursera were obtained using steam distillation and were subjected to tandem GC-MS analysis for identification of the main constituents. The most abundant components of steam volatiles were monoterpenoids from which alpha-terpineol, terpinen-4-ol, alpha-thujene, linalool and limonene were most frequently isolated. A series of sesquiterpenes and long-chain hydrocarbons were isolated and identified from the barks of some of the studied species . Some volatiles were assayed for anti-inflammatory activity using the TPA-induced ear edema bioassay in mice. The volatile fraction from Bursera lancifolia was about half as active as indomethacin.
Full Text Available Much of the coniferous forest in Bulgaria is struck by Ips typographus, Ips acuminatus and Ips sexdentatus beetles. The multispectral camera test near the town of Kalofer, Bulgaria in August 2017, showed the good capabilities of remote-piloted aircraft for observation and mapping of large areas in highly intersected areas. The collected data from the multispectral camera allowed producing maps with different indices of the observed vegetation. Beetles damaged stains were identified and outlining the areas of intervention and their sizing is possible by forestry specialists. The NDVI index in the range of 0.7 to 0.95 characterizes green tree vegetation. Affected forest subjected to stress has lower NDVI index values - 0.65.The NDVI index of damaged areas range from 0.45-0.5. Identifying affected forest areas is the first important step to solve the problem. Taking pictures of drones and multispectral camera can be of great help, and the test conducted clearly demonstrates it. Preventive actions can happen much earlier before trees are completely destroyed and the problem is clearly visible with the naked eye. In view of the rapid spread and the complete destruction of some conifers, immediate action is needed to cut out and remove the diseased and infected trees in order to break the development cycle and prevent subsequent contamination of adjacent plots
Kristin M. Mikkelson
Full Text Available Forested ecosystems throughout the world are experiencing increases in the incidence and magnitude of insect-induced tree mortality with large ecologic ramifications. Interestingly, correlations between water quality and the extent of tree mortality in Colorado montane ecosystems suggest compensatory effects from adjacent live vegetation that mute responses in less severely impacted forests. To this end, we investigated whether the composition of the soil bacterial community and associated functionality beneath beetle-killed lodgepole pine was influenced by the extent of surrounding tree mortality. The most pronounced changes were observed in the potentially active bacterial community, where alpha diversity increased in concert with surrounding tree mortality until mortality exceeded a tipping point of ~30 to 40%, after which diversity stabilized and decreased. Community structure also clustered in association with the extent of surrounding tree mortality with compositional trends best explained by differences in NH4+ concentrations and C/N ratios. C/N ratios, which were lower in soils under beetle-killed trees, further correlated with the relative abundance of putative nitrifiers and exoenzyme activity. Collectively, the response of soil microorganisms that drive heterotrophic respiration and decay supports observations of broader macroscale threshold effects on water quality in heavily infested forests and could be utilized as a predictive mechanism during analogous ecosystem disruptions.
Full Text Available A new endogean bembidiine ground beetle species, Winklerites serbicus sp. n., from a cave in the southeastern part of Serbia is both described and diagnosed. Male and female genital structures and other taxonomically important characters are illustrated. The new species is clearly distinct from its closest congeners. Fifteen species of the genus so far known are arranged in six groups. The new species is both endemic and relict, inhabiting southeastern Serbia only. [Projekat Ministarstva nauke Republike Srbije, br. 173038 i br. 47007
John D. Waldron; Robert N. Coulson; David M. Cairns; Charles W. Lafon; Maria D. Tchakerian; Weimin Xi; Kier Klepzig; Andrew. Birt
The southern pine beetle, Dendroctonus frontalis (Zimmerman) (Coleoptera: Curculionidae: Scolytinae) (SPB), is an indigenous invasive species that infests and causes mortality to pines (Pinus spp.) throughout the Southern United States. The hemlock woolly adelgid, Adelges tsugae (Annand) (Homoptera:...
Chaladze, Giorgi; Kalatozishvili, Levan; Janiashvili, Zurab; Bakuradze, Giorgi
A new species of ground beetles (Coleoptea: Carabidae) belonging to the subgenus Aphaonus Reitter, 1887 (genus Pterostichus Bonelli, 1810) is described, based on two specimens collected from the sacred grove of Khevsha (Eastern Georgia).
The emerald ash borer (EAB; Agrilus planipennis) is an introduced Asian beetle species that was first detected in trees in the Fraxinus (ash) genus in the United States in 2002. Female EAB beetles lay between 40 to 70 eggs in cracks, crevices, and beneath bark flakes. The eggs hatch within about 2 weeks, larvae bore through the...
Kleespies, Regina G; Lim, Young Woon; Tkaczuk, Cezary
Ips sexdentatus (six-spined engraver beetle) from Austria and Poland were dissected and examined for the presence of pathogens. Specimens collected in Austria were found to contain the ascomycetous fungus Metschnikowia cf. typographi. Infection rates ranged from 3.6% to 26.8% at different...... collection sites. M. cf. typographi infected midguts were investigated by histological, ultrastructural and molecular techniques. Extraordinary ultrastructural details are shown, such as ascospores with bilateral flattened flanks resembling alar rims at both sides of their attenuating tube-like ends....... The eugregarine Gregarina typographi was diagnosed most frequently. Infection rates of all I. sexdentatus specimens ranged from 21.4% to 71.9% in Austria and 54.1% to 68.8% in Poland. Other entomopathogenic protists, bacteria, or viruses were not detected....
Newell, P.; King, S.
Partial cutting techniques are increasingly advocated and used to create habitat for priority wildlife. However, partial cutting may or may not benefit species dependent on deadwood; harvesting can supplement coarse woody debris in the form of logging slash, but standing dead trees may be targeted for removal. We sampled cerambycid beetles during the spring and summer of 2006 and 2007 with canopy malaise traps in 1- and 2-year-old partial cut and uncut bottomland hardwood forests of Louisiana. We captured a total of 4195 cerambycid beetles representing 65 species. Relative abundance was higher in recent partial cuts than in uncut controls and with more dead trees in a plot. Total species richness and species composition were not different between treatments. The results suggest partial cuts with logging slash left on site increase the abundance of cerambycid beetles in the first few years after partial cutting and that both partial cuts and uncut forest should be included in the bottomland hardwood forest landscape.
Driscoll, Don A; Kirkpatrick, Jamie B; McQuillan, Peter B; Bonham, Kevin J
1. The general importance of metacommunity and metapopulation theories is poorly understood because few studies have examined responses of the suite of species that occupy the same fragmented landscape. In this study, we examined the importance of spatial ecological theories using a large-scale, naturally fragmented landscape. 2. We measured the occurrence and abundance of 44 common beetle species in 31 natural rainforest fragments in Tasmania, Australia. We tested for an effect on beetle distribution of geographic variables (patch area, patch isolation and amount of surrounding habitat) and of environmental variables based on plant species, after first accounting for spatial autocorrelation using principal coordinates of neighbour matrices. The environmental variables described a productivity gradient and a post-fire succession from eucalypt-dominated forest to late-successional rainforest. 3. Few species had distributions consistent with a metapopulation. However, the amount of surrounding habitat and patch isolation influenced the occurrence or abundance of 30% of beetle species, implying that dispersal into or out of patches was an important process. 4. Three species showed a distribution that could arise by interactions with dominant competitors or predators with higher occurrence in small patches. 5. Environmental effects were more commonly observed than spatial effects. Twenty-three per cent of species showed evidence of habitat-driven, deterministic metapopulations. Furthermore, almost half of the species were influenced by the plant succession or productivity gradient, including effects at the within-patch, patch and regional scales. The beetle succession involved an increase in the frequency of many species, and the addition of new species, with little evidence of species turnover. Niche-related ecological theory such as the species-sorting metacommunity theory was therefore the most broadly applicable concept. 6. We conclude that classic and source
Full Text Available A new species of the Andean stag beetle genus Auxicerus Waterhouse, 1883 is described from the humid Tucuman-Bolivian forest in the southern Bolivian Andes. Auxicerus magnipunctatus sp. nov. is distinguished from all congeners by the distinctly larger punctures of the mesosternum; antennomeres 2–6 subquadrate, last two joints of club wider than long; lamellae not widely separated; posterior end of ocular canthus rounded and anterior edge of canthus moderately developed into an obtuse triangle. Auxicerus magnipunctatus sp. nov. is possibly endemic to the Tucuman-Bolivian forest. Along with the presence of other endemic beetle species with tropical congeners, the discovery of A. magnipunctatus sp. nov. supports the idea that the persistence of rather tropical taxa in the subtropical realm is fostered by increased humidity at orographic rain barriers and climatic stability in the Tucuman-Bolivian forest.
Albert E. Mayfield; James L. Hanula
The redbay ambrosia beetle, Xyleborus glabratus Eichhoff, is a non-native invasive pest and vector of the fungus that causes laurel wilt disease in certain trees of the family Lauraceae. This study assessed the relative attractiveness and suitability of cut bolts of several tree species to X. glabratus. In 2009, female X. glabratus were equally attracted to traps...
Beetles in the genus Delphastus Casey are small whitefly-specific predatory ladybird beetles belonging to the coccinellid tribe Serangiini. They feed on all immature stages of whitefly and are reared and sold commercially all over the world for this purpose. They are compatible with the application ...
Daniel R. Miller; Donald A. Duerr
We compared the effectiveness of a dry collection cup (with an insecticide killing strip) to a wet collection cup (containing antifreeze) for use with Lindgren multiple-funnel traps in catching several common species of bark and wood-boring beetles, and their associates in southern pine forests. All traps were baited with either the binary combination of ethanol and...
Tane, Z.; Ramirez, C.; Roberts, D. A.; Koltunov, A.; Sweeney, S.
There is considerable scientific and public interest in the ongoing drought and bark beetle driven conifer mortality in the Central and Southern Sierra Nevada, the scale of which has not been seen previously in California's recorded history. Just before and during this mortality event (2013-2016), Airborne Visible / Infrared Imaging Spectrometer (AVIRIS) data were acquired seasonally over part of the affected area as part of the HyspIRI Preparatory Mission. In this study, we used 11 AVIRIS flight lines from 8 seasonal flights (from spring 2013 to summer 2015) to detect conifer mortality. In addition to the standard pre-processing completed by NASA's Jet Propulsion Lab, AVIRIS images were co-registered and georeferenced between time steps and images were resampled to the spatial resolution and signal-to-noise ratio expected from the proposed HyspIRI satellite. We used summer 2015 high-spatial resolution WorldView-2 and WorldView-3 images from across the study area to collect training data from five scenes, and independent validation data from five additional scenes. A cover class map developed with a machine-learning algorithm, separated pixels into green conifer, red-attack conifer, and non-conifer dominant cover, yielding a high accuracy (above 85% accuracy on the independent validation data) in the tree mortality final map. Discussion will include the effects of temporal information and input dimensionality on classification accuracy, comparison with multi-spectral classification accuracy, the ecological and forest management implications of this work, incorporating 2016 AVIRS images to detect 2016 mortality, and future work in understanding the spatial patterns underlying the mortality.
Full Text Available Mountain forests in National park Bohemian Forest (Czech Republic were affected by bark beetle attack and windthrows in 2004-2008, followed by an extensive tree dieback. We evaluated changes in the biochemistry of the uppermost soil horizons with the emphasis on carbon (C and nitrogen (N cycling in a near-natural spruce (Picea abies mountain forest after the forest dieback, and compared it with an undisturbed control plot of similar age, climate, elevation, deposition, N-saturation level, and land use history. We hypothesised that the high litter input after forest dieback at the disturbed plot and its consequent decomposition might influence the availability of C for microorganisms, and consequently, N transformations in the soil. The concentrations of dissolved organic C (DOC and N (DON in soil water extracts rapidly increased at the disturbed plot for 3 yeas and then continually decreased. Net ammonification exhibited a similar trend as DOC and DON, indicating elevated mineralization. Despite the high ammonium concentrations found after the forest dieback (an increase from 0.5 mmol kg-1 to 2-3 mmol kg-1, net nitrification was stable and low during these 3 years. After the DOC depletion and decrease in microbial biomass 5 years after the forest dieback, net nitrification started to rise, and nitrate concentrations increased from 0.2-1 mmol kg-1 to 2-3 mmol kg-1. Our results emphasize the key role of the availability of organic C in microbial N transformations, which probably promoted microbial heterotrophic activity at the expense of slow-growing nitrifiers.
Ryan R. Bracewell; Michael E. Pfrender; Karen E. Mock; Barbara J. Bentz
Studies of postzygotic isolation often involve well-differentiated taxa that show a consistent level of incompatibility, thereby limiting our understanding of the initial stages and development of reproductive barriers. Dendroctonus ponderosae provides an informative system because recent evidence suggests that distant populations produce hybrids with reproductive...
Rosenberger, Derek W.; Venette, Robert C.; Maddox, Mitchell P.; Aukema, Brian H.
As climates change, thermal limits may no longer constrain some native herbivores within their historical ranges. The mountain pine beetle, Dendroctonus ponderosae Hopkins, is a tree-killing bark beetle native to western North America that is currently expanding its range. Continued eastward expansion through the newly invaded and novel jack pine (Pinus banksiana Lamb.) trees of the Canadian boreal forest could result in exposure of several species of novel potential host pines common in nort...
Full Text Available Ecological immunology is an interdisciplinary field that helps elucidate interactions between the environment and immune response. The host species individuals experience have profound effects on immune response in many species of insects. However, this conclusion comes from studies of herbivorous insects even though species of mycophagous insects also inhabit many different host species. The goal of this study was to determine if fungal host species as well as individual, sex, body size, and host patch predict one aspect of immune function, phenoloxidase activity (PO. We sampled a metapopulation of Bolitotherus cornutus, a mycophagous beetle in southwestern Virginia. B. cornutus live on three species of fungus that differ in nutritional quality, social environment, and density. A filter paper phenoloxidase assay was used to quantify phenoloxidase activity. Overall, PO activity was significantly repeatable among individuals (0.57 in adult B. cornutus. While there was significant variance among individuals in PO activity, there were surprisingly no significant differences in PO activity among subpopulations, beetles living on different host species, or between the sexes; there was also no effect of body size. Our results suggest that other factors such as age, genotype, disease prevalence, or natal environment may be generating variance among individuals in PO activity.
Fujimaki, Kotaro; Fujisawa, Tomochika; Yazawa, Shigenobu; Nishimura, Osamu; Sota, Teiji
Ground beetles of the subgenus Ohomopterus (genus Carabus) show marked divergence in species-specific male and female genital morphologies, which contributes to reproductive isolation among species. Characterizing the genetic basis of species-specific genital morphology is essential for understanding their diversification, but genomic information on Ohomopterus is not yet available. We analyzed mRNA extracted from abdominal sections of the last instar larvae and pupae of two sister species, Carabus (Ohomopterus) iwawakianus and C. (O.) uenoi, which show marked differences in genital morphology, to compare transcriptomic profiles using Roche 454 pyrosequencing. We obtained 1,608,572 high-quality reads and assembled them into 176,278 unique sequences, of which 66,049 sequences were combined into 12,662 clusters. Differential expression analyses for sexed pupae suggested that four and five clusters were differentially expressed between species for males and females, respectively. We also identified orthologous sequences of genes involved in genital development in Drosophila, which potentially affect genital development and species-specific genital morphology in Ohomopterus. This study provides the first large transcriptomic data set for a morphologically diversified beetle group, which can facilitate future studies on the genetic basis of species-specific genitalia.
Miller, D R; Asaro, C; Berisford, C W
We determined the response of the small southern pine engraver, Ips avulsus (Eichhoff); eastern fivespined ips, Ips grandicollis (Eichhoff); sixspined ips, Ips calligraphus (Germar); and pine engraver, Ips pini (Say) to the pheromones (+/-)-ipsenol, (+/-)-ipsdienol, and lanierone in the southeastern United States. Catches of I. avulsus and I. grandicollis to baited multiple-funnel traps were increased by (+/-)-ipsenol and (+/-)-ipsdienol in Florida, Georgia, Louisiana, and North Carolina. In all four localities, the highest numbers of I. avulsus were caught in traps baited with the combination of (+/-)-ipsenol, (+/-)-ipsdienol, and lanierone. In Florida, the highest numbers of I. grandicollis were captured in traps baited with the combination of (+/-)-ipsenol and (+/-)-ipsdienol (with or without lanierone). In the remaining three localities, the largest catches of I. grandicollis occurred in traps baited with (+/-)-ipsenol alone or the combination of (+/-)-ipsenol and (+/-)-ipsdienol (with or without lanierone). (+/-)-Ipsdienol was the only consistent attractant for I. calligraphus and I. pini. Attraction of I. pini in North Carolina to (+/-)-ipsdienol-baited traps was synergized by lanierone but interrupted with (+/-)-ipsenol. The interruptive effect of (+/-)-ipsenol on attraction of I. pini to (+/-)-ipsdienol was negated by lanierone. (+/-)-Ipsdienol was attractive to black turpentine beetle, Dendroctonus terebrans (Olivier), in Florida but not North Carolina, whereas (+/-)-ipsdienol was attractive to I. calligraphus in Louisiana, Georgia, and Florida. Both (+/-)-ipsenol and (+/-)-ipsdienol affected catches of Gnathotrichus materiarus (Fitch) in North Carolina. Trap catches of Hylurgops rugipennis pinifex (Fitch), Hylastes salebrosus Eichhoff, and Hylastes tenuis Eichhoff were unaffected by the pheromone treatments. The combination of (+/-)-ipsenol, (+/-)-ipsdienol, and lanierone may be a cost-effective general lure for I. avulsus, I. grandicollis, and I. pini.
L.M. Hanks; J.A. Mongold-Diers; T.H. Atkinson; M.K. Fierke; M.D. Ginzel; E.E. Graham; T.M. Poland; A.B. Richards; M.L. Richardson; J.G.. Millar
Pheromone components of cerambycid beetles are often conserved, with a given compound serving as a pheromone component for multiple related species, including species native to different continents. Consequently, a single synthesized compound may attract multiple species to a trap simultaneously. Furthermore, our previous research in east-central Illinois had...
Mar 31, 2016 ... Re-growth of bark was the most common strategy developed, with mean values ranging from ..... common strategy developed, with mean values over 90% of trees partially debarked. The recruitment of new ..... and relationships with centroid bark content and stem diameter. BioEnergy Research 8(4): 1661-.
Ernst, Crystal M; Hanelt, Ben; Buddle, Christopher M
The host-parasite associations between ground beetles (Coleoptera: Carabidae) and hairworms (Nematomorpha: Gordiida) collected from the Arctic (an understudied and ecologically important region) is described. Carabids and their parasites were collected from 12 sites spanning the 3 northernmost ecoclimatic zones of Canada (north boreal, subarctic, and high Arctic) using standardized methods. The beetles and hairworms were identified using traditional morphological approaches. Seven beetle species are recorded as hosts: Amara alpina, Pterostichus caribou, Pterostichus brevicornis, Pterostichus tareumiut, Pterostichus haematopus, Patrobus septentrionis, and Notiophilus borealis. All represent new host records (increasing the known North American host list from 14 to 21), and this is the first record of hairworm infection in the genus Notiophilus. Beetles from Banks Island, Northwest Territory, were infected in high numbers (11-19% per sampling period) and were used as an ecological case study. There was no significant relationship between infection status and host species, body size, or sex. Beetles collected in yellow pan traps and in wet habitats were more likely to be infected, likely due to water-seeking behavior induced by the parasites. Morphological examinations indicate that the hairworms collected from all locations represent a single, new species of Gordionus, making it only the sixth hairworm species and the third species of that genus found in Canada. Hosts are unknown for all other Canadian (and 1 Alaskan) Gordionus species.
Richard A. Goyer; Kier D. Klepzig
Without a doubt, bark beetles are the most destructive insect pests of Southern pines. Among these, the Southern pine beetle (SPB), Dendroctonus frontalis, isi the most notable and most noticed. During outbreak years, this small, but very aggresive, beetle can cause catastrophic losses.
Aguilar Lopez, Jorge; Vega Guzman, Ileana; Borbon Alpizar, Henry; Soto Fallas, Roy Mario; Jaen Jimenez, Jean Carlo; Vargas Abarca, Ana Sofia; Jimenez Bonilla, Pablo; Herrera Nunez, Jacqueline
A study is made regarding the nature and the amount of condensed tannin which can extract of bark from 11 tree species present in Costa Rica: guanacaste (Enterolobium cyclocarpum), cork oak (Licania arborea), jobo (Spondias mombin), pochote (Pachira quinata), loquat (Manilkara chicle), almond (Andira inermis), oak (Tabebuia rosea), cedar (Cedrela odorata), cenizaro (Samanea saman), pine (Pinus caribaea) and cypress (Cupressus lusitanica). The cortex samples were prepared, dried and extracted with ethanol. The ethanolic extracts were analyzed for condensed tannin content through the number of Stiasny, and characterized by infrared spectroscopy (FT-IR). The species with the highest proportion of extracted material were: guanacaste (9.5841% w/w), pochote (15.0066% w/w), pine (19.3400% w/w) and cypress (10.5300% w/w). The extracts with a higher proportion of condensed tannins have been: cork oak (61.9% w/w), jobo (66.1% w/w), pochote (72.8% w/w), loquat (50.5% w/w), cedar (72.7% w/w) and pine (70.7% w/w). (author) [es
Mathew L. Brust
Full Text Available Nonexpert citizen groups are being used to monitor species to track ecosystem changes; however, challenges remain for proper identification, especially among diverse groups such as beetles. Tiger beetles, Cicindela spp., have been used for biological diversity monitoring because of their diversity and the ease of recognition. The finding of an apparent hybrid zone among Cicindela denverensis Casey, Cicindela limbalis Klug, and Cicindela splendida Hentz in central Nebraska prompted a detailed study of the biogeography of this species group within Nebraska, a test of characteristics that could be used by citizen scientists, and limited breeding experiments. This study suggests that while C. denverensis appears to hybridize with both C. limbalis and C. splendida within the hybrid zone, all three species maintain their integrity across most of their ranges, largely occupy unique geographic regions, and at least C. denverensis and C. splendida cooccur in many areas with no evidence of hybridization. Evidence of hybridization between C. limbalis and C. splendida was found at only two sites. Furthermore, breeding experiments with virgin C. splendida and C. denverensis showed that they are capable of producing hybrid larvae in the laboratory. The presence of morphological intergrades serves as a cautionary note when using biological indicator species.
Coyle, D R; D.C. Booth: M.S. Wallace
ABSTRACT In spring 2002, ambrosia beetles (Coleoptera: Scolytidae) infested an intensively managed 22-ha tree plantation on the upper coastal plain of South Carolina. Nearly 3,500 scolytids representing 28 species were captured in ethanol-baited traps from 18 June 2002 to 18 April 2004. More than 88% of total captures were exotic species. Five species [Dryoxylon onoharaensum (Murayama), Euwallacea validus (Eichhoff), Pseudopityophthorus minutissimus (Zimmermann), Xyleborus atratus Eichhoff, and Xyleborus impressus Eichhoff]) were collected in South Carolina for the first time. Of four tree species in the plantation, eastern cottonwood, Populus deltoides Bartram, was the only one attacked, with nearly 40% of the trees sustaining ambrosia beetle damage. Clone ST66 sustained more damage than clone S7C15. ST66 trees receiving fertilization were attacked more frequently than trees receiving irrigation, irrigation_fertilization, or controls, although the number of S7C15 trees attacked did not differ among treatments. The study location is near major shipping ports; our results demonstrate the necessity for intensive monitoring programs to determine the arrival, spread, ecology, and impact of exotic scolytids.
Ewers, B. E.; Mackay, D. S.; Guadagno, C.; Peckham, S. D.; Pendall, E.; Borkhuu, B.; Aston, T.; Frank, J. M.; Massman, W. J.; Reed, D. E.; Yarkhunova, Y.; Weinig, C.
Recent work has shown that nonstructural carbon (NSC) provides both a signal and consequence of water stress in plants. The dynamics of NSC are likely not solely a result of the balance of photosynthesis and respiration (carbon starvation hypothesis) but also the availability of NSC for plant functions due to hydraulic condition. Further, plant hydraulics regulates photosynthesis both directly through stomatal conductance and indirectly through leaf water status control over leaf biochemistry. To test these hypotheses concerning NSC in response to a wide variety of plant perturbations, we used a model that combines leaf biochemical controls over photosynthesis (Farquhar model) with dynamic plant hydraulic conductance (Sperry model). This model (Terrestrial Regional Ecosystem Exchange Simulator; TREES) simulates the dynamics of NSC through a carbon budget approach that responds to plant hydraulic status. We tested TREES on two dramatically different datasets. The first dataset is from lodgepole pine and Engelmann spruce trees dying from bark beetles that carry blue-stain fungi which block xylem and cause hydraulic failure. The second data set is from Brassica rapa, a small herbaceous plant whose accessions are used in a variety of crops. The Brassica rapa plants include two parents whose circadian clock periods are different; NSC is known to provide inputs to the circadian clock likely modified by drought. Thus, drought may interact with clock control to constrain how NSC changes over the day. The Brassica rapa plants were grown in growth chamber conditions where drought was precisely controlled. The connection between these datasets is that both provide rigorous tests of our understanding of plant NSC dynamics and use similar leaf and whole plant gas exchange and NSC laboratory methods. Our results show that NSC decline (<10% in the whole plant) is less precipitous than expected from carbon starvation alone because both C uptake and use are impacted by water stress
C.J. Fettig; S.R. McKelvey
Highly effective fire suppression and selective harvesting of large-diameter, fire-tolerant tree species, such as ponderosa pine (Pinus ponderosa C. Lawson) and Jeffrey pine (P. jeffreyi Balf.), have resulted in substantial changes to the structure and composition of interior ponderosa pine forests. Mechanical thinning and the...
Nadir Erbilgin; Brice A. McPherson; Pierluigi Bonello; David L. Wood; Andrew J. Nelson
Sudden oak death (SOD) has had devastating effects on several oak species in many California coastal forests. Phytophthora ramorum has been identified as the primary causal agent of sudden oak death. While the pathogen may be capable of killing mature trees, it is likely that in nature opportunistic organisms play significant roles in the decline and...
Sharon M. Hood; Stephen Baker; Anna Sala
Fire frequency in low-elevation coniferous forests in western North America has greatly declined since the late 1800s. In many areas, this has increased tree density and the proportion of shade-tolerant species, reduced resource availability, and increased forest susceptibility to forest insect pests and high-severity wildfire. In response, treatments are...
Data are tabulated and discussed from pulping, beating and washing experiments on pulps including various proportions of the bark and leaves of 4 species: Aspen (Populus tremula), Sallow (Salix caprea), White Birch (Betula pubescens) and Grey Alder (Alnus incana). Leaves were found to be unsuitable as a raw material, but the yields and strength of pulps including bark were satisfactory. The main problem in the use of these pulps is their bad drainage characteristics; this calls for either more washing capacity or for a chip barking process. An economic analysis indicates that it is best to use unbarked stems of these species at age 20 to 25.
Cornelisse, Tara M; Duane, Timothy P
Recreation is a leading cause of species decline on public lands, yet sometimes it can be used as a tool for conservation. Engagement in recreational activities, such as hiking and biking, in endangered species habitats may even enhance public support for conservation efforts. We used the case of the endangered Ohlone tiger beetle (Cicindela ohlone) to investigate the effect of biking and hiking on the beetle's behavior and the role of recreationists' knowledge of and attitudes toward Ohlone tiger beetle in conservation of the species. In Inclusion Area A on the University of California Santa Cruz (U.S.A.) campus, adult Ohlone tiger beetles mate and forage in areas with bare ground, particularly on recreational trails; however, recreation disrupts these activities. We tested the effect of recreation on Ohlone tiger beetles by observing beetle behavior on trails as people walked and road bikes at slow and fast speed and on trails with no recreation. We also surveyed recreationists to investigate how their knowledge of the beetle affected their attitudes toward conservation of the beetle and stated compliance with regulations aimed at beetle conservation. Fast cycling caused the beetles to fly off the trail more often and to fly farther than slow cycling or hiking. Slow cycling and hiking did not differ in their effect on the number of times and distance the beetles flew off the trail. Recreationists' knowledge of the beetle led to increased stated compliance with regulations, and this stated compliance is likely to have tangible conservation outcomes for the beetle. Our results suggest management and education can mitigate the negative effect of recreation and promote conservation of endangered species. Efectos del Conocimiento de una Especie en Peligro sobre las Actitudes y Comportamientos Declarados de los Recreacionistas y el Significado del Manejo de la Conformidad para la Conservación del Escarabajo Tigre de Ohlone. © 2013 Society for Conservation Biology.
Kijimoto, Teiya; Moczek, Armin P; Andrews, Justen
Sex-specific trait expression is frequently associated with highly variable, condition-dependent expression within sexes and rapid divergence among closely related species. Horned beetles are an excellent example for studying the molecular basis of these phenomena because horn morphology varies markedly among species, between sexes, and among alternative, nutritionally-cued morphs within sexes. In addition, horns lack obvious homology to other insect traits and provide a good opportunity to explore the molecular basis of the rapid diversification of a novel trait within and between species. Here we show that the sex-determination gene doublesex (dsx) underlies important aspects of horn development, including differences between sexes, morphs, and species. In male Onthophagus taurus, dsx transcripts were preferentially expressed in the horns of the large, horned morph, and RNAi-mediated knockdown of dsx dramatically altered male horn allometry by massively reducing horn development in large males, but not in smaller males. Conversely, dsx RNAi induced ectopic, nutrition-sensitive horn development in otherwise hornless females. Finally, in a closely related species (Onthophagus sagittarius) that has recently evolved a rare reversed sexual dimorphism, dsx RNAi revealed reversed as well as novel dsx functions despite an overall conservation of dsx expression. This suggests that rapid evolution of dsx functions has facilitated the transition from a regular sexual dimorphism to a reversed sexual dimorphism in this species. Our findings add beetle horns to existing examples of a close relationship between dsx and sexual trait development, and suggest that dsx function has been coopted to facilitate both the evolution of environmentally-cued intrasexual dimorphisms and rapid species divergences in a novel trait.
Paul J. Johnson
Full Text Available The beetle family Throscidae is documented from Peru for the first time, based on specimens collected in the regions of Cajamarca, Junín, Loreto and Madre de Dios. Aulonothroscus tambopata new species is described from Madre de Dios. Also, three additional species of Aulonothroscus are reported from Peru for the first time – A. alvarengai Cobos new country record, A. freudi Cobos new country record, and A. oculatissimus Cobos new country record. A key separating these four species is given. This report is part of the “Beetles of Peru” project.
Sipos, J; Hodecek, J; Kuras, T; Dolny, A
Although ecological succession is one of the principal focuses of recent restoration ecology research, it is still unclear which factors drive this process and positively influence species richness and functional diversity. In this study we sought to elucidate how species traits and functional diversity change during forest succession, and to identify important factors that determine the species in the observed assemblages. We analyzed species richness and functional diversity of ground beetle assemblages in relation to succession on post-industrial localities after habitat deterioration caused by spoil deposition. We selected ground beetles as they are known to be sensitive to landscape changes (with a large range of responses), and their taxonomy and ecology are generally well-known. Ground beetles were sampled on the spoil heaps during the last 30 years when spontaneous succession occurred. To calculate functional diversity, we used traits related to habitat and trophic niche, i.e. food specialization, wing morphology, trophic level, and bio-indication value. Ground beetle species were found to be distributed non-randomly in the assemblages in the late phase of succession. Ordination analyses revealed that the ground beetle assemblage was significantly associated with the proportion of forested area. Environmental heterogeneity generated assemblages that contained over-dispersed species traits. Our findings indicated that environmental conditions at late successional stages supported less mobile carnivorous species. Overall, we conclude that the decline in species richness and functional diversity in the middle of the studied succession gradient indicated that the assemblages of open habitats had been replaced by species typical of forest ecosystems.
Yanai, R. D.; Yang, Y.; Driscoll, C. T.; Montesdeoca, M.
Mercury (Hg) deposition affects forests even in remote areas, but the amount of Hg in trees is not well known, in part because concentrations of Hg in wood are often below the analytical detection limit by ICP-OES. We analyzed Hg in wood, bark, and foliage of 8 tree species across four sites (Huntington Forest, NY; Sleepers River, VT; Hubbard Brook, NH; Bear Brook, ME) in the northeastern USA, using thermal decomposition, catalytic conversion, amalgamation, and atomic absorption spectrophotometry (USEPA Method 7473). The hardwood species, namely American beech (Fagus grandifolia Ehrh.), white ash (Fraxinus americana L.), yellow birch (Betula alleghaniensis Britt.), sugar maple (Acer saccharum Marshall.), and red maple (Acer rubrum L.), had lower Hg concentrations (averaging 7.7 ng g-1 in bark and 16.3 ng g-1 in foliage) than the conifers, namely red spruce (Picea rubens Sarg.), balsam fir (Abies balsamea (L.) Mill.) and white pine (Pinus strobus L.) (averaging 22.5 ng g-1 in bark and 28.6 ng g-1 in foliage) (p < 0.001). Yellow birch had especially high Hg in wood (2.5 ng g-1) (p < 0.001); the other species averaged 1.4 ng g-1. The Hg content of aboveground biomass, estimated from modeled tree biomass and species composition at each site, declined from the west to the east. Wood is important to Hg budgets in spite of low concentrations, because of its large mass. With the proper analytical methods, it is possible to estimate pools and fluxes of Hg in forest vegetation.
Ćurčić Srećko B.
Full Text Available A new species of endogean carabid beetles (Javorella suvodolensis n. sp has been described from under stones, village Debelja, near Nova Varoš, Mt. Javor, southwestern Serbia. This new species is easily distinguished from all other phenetically close congeners in many important respects such as the body size, body shape, shape of head, form and size of eyes, number of ommatidia, length of antennae, shape of pronotum, shape of elytra, relative position of humeral setae, structure and form of female genitalia and the shape of the gonosternite. Javorella suvodolensis n. sp. is the first known endogean species of the genus Javorella S. B. Ćurčić, M. M. Brajković & B. P. M. Ćurčić [apart from the cavernicolous species Javorella suvoborensis (Pavićević & Popović and Javorella javorensis Ćurčić, Brajković & Ćurčić]. This new species and its congeners belong to an old separate phyletic lineage, distinct from all other related species groups. Additionally, J. suvodolensis n. sp. is relic and endemic to the mountains of southwest Serbia.
Sim, Sheina B; Yoneishi, Nicole M; Brill, Eva; Geib, Scott M; Follett, Peter A
The coffee berry borer, Hypothenemus hampei (Ferrari) (Coleoptera: Curculionidae), is a serious pest of coffee worldwide. It was first detected in Hawai'i in 2010. Two predatory beetles, Cathartus quadricollis (Coleoptera: Silvanidae) and Leptophloeus sp. (Coleoptera: Laemophloeidae), have been observed in H. hampei-infested coffee. Under laboratory conditions, colony-reared C. quadricollis and Leptophloeus sp. prey upon all life stages of H. hampei. However, the H. hampei life cycle occurs almost exclusively within a coffee bean obscured from direct observation. Thus, it is unknown if C. quadricollis and Leptophloeus sp. consume H. hampei as prey in the wild. To demonstrate predation of H. hampei by C. quadricollis and Leptophloeus sp., a molecular assay was developed utilizing species-specific primers targeting short regions of the mitochondrial COI gene to determine species presence. Using these primers, wild C. quadricollis and Leptophloeus sp. were collected and screened for the presence of H. hampei DNA using PCR. Analysis of collections from five coffee farms revealed predation of C. quadricollis and Leptophloeus sp. on H. hampei. Further laboratory testing showed that H. hampei DNA could be detected in predators for as long as 48 h after feeding, indicating the farm-caught predators had preyed on H. hampei within 2 d of sampling. This study demonstrates the utility of molecular markers for the study of the ecology of predators and prey with cryptic behavior, and suggests C. quadricollis and Leptophloeus sp. might be useful biocontrol agents against H. hampei. Published by Oxford University Press on behalf of Entomological Society of America 2015. This work is written by US Government employees and is in the public domain in the US.
Full Text Available Many methods used for estimating species richness are either difficult to use on poorly known taxa or require input data that are laborious and expensive to collect. In this paper we apply a method which takes advantage of the carefully conducted tests of how the described diversity compares to real species richness that are inherent in taxonomic revisions. We analyze the quantitative outcome from such revisions with respect to body size, zoogeographical region and phylogenetic relationship. The best fitting model is used to predict the diversity of unrevised groups if these would have been subject to as rigorous species level hypothesis-testing as the revised groups. The sensitivity of the predictive model to single observations is estimated by bootstrapping over resampled subsets of the original data. The Dytiscidae is with its 4080 described species (end of May 2009 the most diverse group of aquatic beetles and have a world-wide distribution. Extensive taxonomic work has been carried out on the family but still the number of described species increases exponentially in most zoogeographical regions making many commonly used methods of estimation difficult to apply. We provide independent species richness estimates of subsamples for which species richness estimates can be reached through extrapolation and compare these to the species richness estimates obtained through the method using revision data. We estimate there to be 5405 species of dytiscids, a 1.32-fold increase over the present number of described species. The undescribed diversity is likely to be biased towards species with small body size from tropical regions outside of Africa.
Beetle wings perform a flapping movement, consisting of the rotation relative to the two axes. This paper presents the results of observations and measurements of wings operating parameters in different planes of some beetle species. High speed photos and videos were used. The concept of the mechanism performing a complex wing movement was proposed and developed.
Full Text Available Beetle wings perform a flapping movement, consisting of the rotation relative to the two axes. This paper presents the results of observations and measurements of wings operating parameters in different planes of some beetle species. High speed photos and videos were used. The concept of the mechanism performing a complex wing movement was proposed and developed.
Dean L. Parry; Gregory M. Filip; Susan A. Willits; Catherine G. Parks
The purpose of this study was to determine the effect of time since death over a 4-year period on the amount of usable product volume and value, and to determine the species of fungi associated with wood deterioration in the stems of Douglas-fir and grand fir trees killed by bark beetles in northeastern Oregon. Sap rot, caused principally by Cryptoporus...
Raffa, Kenneth F; Mason, Charles J; Bonello, Pierluigi; Cook, Stephen; Erbilgin, Nadir; Keefover-Ring, Ken; Klutsch, Jennifer G; Villari, Caterina; Townsend, Philip A
Warming climate is allowing tree-killing bark beetles to expand their ranges and access naïve and semi-naïve conifers. Conifers respond to attack using complex mixtures of chemical defences that can impede beetle success, but beetles exploit some compounds for host location and communication. Outcomes of changing relationships will depend on concentrations and compositions of multiple host compounds, which are largely unknown. We analysed constitutive and induced chemistries of Dendroctonus ponderosae's primary historical host, Pinus contorta, and Pinus albicaulis, a high-elevation species whose encounters with this beetle are transitioning from intermittent to continuous. We quantified multiple classes of terpenes, phenolics, carbohydrates and minerals. Pinus contorta had higher constitutive allocation to, and generally stronger inducibility of, compounds that resist these beetle-fungal complexes. Pinus albicaulis contained higher proportions of specific monoterpenes that enhance pheromone communication, and lower induction of pheromone inhibitors. Induced P. contorta increased insecticidal and fungicidal compounds simultaneously, whereas P. albicaulis responses against these agents were inverse. Induced terpene accumulation was accompanied by decreased non-structural carbohydrates, primarily sugars, in P. contorta, but not P. albicaulis, which contained primarily starches. These results show some host species with continuous exposure to bark beetles have more thoroughly integrated defence syndromes than less-continuously exposed host species. © 2017 John Wiley & Sons Ltd.
Boge, A; Gerstmeier, R; Einspanier, R
Differentiation between Carabus species (ground beetle) and subspecies is difficult, although there have been extensive studies. To address this problem we have applied PCR in combination with SSCP analysis focussing on the evolutionally conservative ubiquitin gene to elaborate a new approach to molecular differentiation between species. We report that Carabidae possess an ubiquitin gene and that its gene has a multimeric structure. Differential SSCP analysis was performed with the monomeric form of the gene to generate a clear SSCP pattern. Such PCR/SSCP resulted in reproducible patterns throughout our experiments. Comparing different Carabus species (Carabus granulatus, C. irregularis, C. violaceus and C. auronitens) we could observe clear interspecies differences but no differences between genders. Some species showed some remarkable differences between the individuals. We suggest that the ubiquitin PCR-SSCP technique might be an additional tool for the differentiation of ground beetles.
Mayfield, A E; Hanula, J L
The redbay ambrosia beetle, Xyleborus glabratus Eichhoff, is a non-native invasive pest and vector of the fungus that causes laurel wilt disease in certain trees of the family Lauraceae. This study assessed the relative attractiveness and suitability of cut bolts of several tree species to X. glabratus. In 2009, female X. glabratus were equally attracted to traps baited with swampbay (Persea palustris (Rafinesque) Sargent) and camphortree (Cinnamomum camphora (L.) J. Presl), which were more attractive than avocado (Persea americana Miller), lancewood (Ocotea coriacea (Swartz) Britton), and sweetbay (Magnolia virginiana L.). These species were more attractive than loblolly bay (Gordonia lasianthus (L.) J. Ellis). X. glabratus entrance hole density and emergence from caged bolts were highest on swampbay and camphortree. In 2010, swampbay was significantly more attractive to X. glabratus than sassafras (Sassafras albidum (Nuttall) Nees), yellow poplar (Liriodendron tulipifera L.), and eastern redbud (Cercis canadensis L.). Sassafras bolts end sealed with a liquid wax-and-water emulsion were more attractive to X. glabratus than end-sealed bolts of yellow poplar and redbud. Relative to unsealed bolts, end seal decreased X. glabratus entrance hole density on swampbay and decreased granulate ambrosia beetle (Xylosandrus crassiusculus (Motschulsky)) trap catch, entrance hole density, and adult emergence from swampbay. X. crassiusculus was not attracted to sassafras, yellow poplar, and redbud and was not more attracted to manuka oil than to unbaited traps. Sassafras was more attractive to X. glabratus than previously reported and supported reproducing populations of the insect. End sealing bolts with a wax-and-water emulsion may not be optimal for attracting and rearing ambrosia beetles in small logs.
Bosly, Hanan AbuAlQasem; Kawanna, Maha Adel
Infection of stored wheat flour with insects and toxic fungi can be an extremely serious problem. This study was conducted to isolate and identify the fungal species and insects in different stages, which infested and contaminated the stored flour under Jazan region conditions and changed its color and flavor. The obtained results revealed that the isolated insect was the red flour beetle Tribolium castaneum. Live adult, larvae and cast skin were isolated. Four Aspergillus species were isolated from stored wheat flour; the isolated species prevalence being A. flavus > A. niveus > A. terreus > A. niger by rate 44.5%, 37.8%, 10.9% and 6.7%, respectively. The same fungal species isolated from flour were also isolated from different insect stages. A. flavus was the most common fungus and A. niger was isolated with a lower rate. The results about the isolated fungi either from the suspension of adult insects, larvae or cast skins may confirm the role of T. castaneum to carry and distribute fungi in different parts of the stored flour.
Six, Diana L; de Beer, Z Wilhelm; Duong, Tuan A; Carroll, Allan L; Wingfield, Michael J
Bark beetles are well known vectors of ophiostomatoid fungi including species of Ophiostoma, Grosmannia and Ceratocystis. In this study, the most common ophiostomatoid fungi associated with the lodgepole pine beetle, Dendroctonus murrayanae, were characterized. Pre-emergent and post-attack adult beetles were collected from lodgepole pines at four sites in British Columbia, Canada. Fungi were isolated from these beetles and identified using a combination of morphology and DNA sequence comparisons of five gene regions. In all four populations, Grosmannia aurea was the most common associate (74-100% of all beetles) followed closely by Ophiostoma abietinum (29-75%). Other fungi isolated, in order of their relative prevalence with individual beetles were an undescribed Leptographium sp. (0-13%), Ophiostoma ips (0-15%), Ophiostoma piliferum (0-11%), a Pesotum sp. (0-11%) and Ophiostoma floccosum (0-1%). Comparisons of the DNA sequences of Leptographium strains isolated in this study, with ex-type isolates of G. aurea, Grosmannia robusta, Leptographium longiclavatum, and Leptographium terebrantis, as well as with sequences from GenBank, revealed a novel lineage within the Grosmannia clavigera complex. This lineage included some of the D. murrayane isolates as well as several isolates from previous studies referred to as L. terebrantis. However, the monophyly of this lineage is not well supported and a more comprehensive study will be needed to resolve its taxonomic status as one or more novel taxa.
Nenadić, Marija; Soković, Marina; Glamočlija, Jasmina; Ćirić, Ana; Perić-Mataruga, Vesna; Ilijin, Larisa; Tešević, Vele; Vujisić, Ljubodrag; Todosijević, Marina; Vesović, Nikola; Ćurčić, Srećko
The antimicrobial properties of the pygidial gland secretions released by the adults of the three ground beetle species, Carabus ullrichii, C. coriaceus, and Abax parallelepipedus, have been tested. Microdilution method was applied for detection of minimal inhibitory concentrations (MICs), minimal bactericidal concentrations (MBCs), and minimal fungicidal concentrations (MFCs). Additionally, morpho-histology of the pygidial glands is investigated. We have tested 16 laboratory and clinical strains of human pathogens—eight bacterial both gram-positive and gram-negative species and eight fungal species. The pygidial secretion samples of C. ullrichii have showed the strongest antimicrobial effect against all strains of treated bacteria and fungi. Staphylococcus aureus, Lysteria monocytogenes, and Salmonella typhimurium proved to be the most sensitive bacterial strains. Penicillium funiculosum proved to be the most sensitive micromycete, while P. ochrochloron and P. verrucosum var . cyclopium the most resistant micromycetes. The pygidial secretion of C. coriaceus has showed antibacterial potential solely against Pseudomonas aeruginosa and antifungal activity against Aspergillus fumigatus, A. versicolor, A. ochraceus, and P. ochrochloron. Antibacterial properties of pygidial gland secretion of A. parallelepipedus were achieved against P. aeruginosa, while antifungal activity was detected against five of the eight tested micromycetes (A. fumigatus, A. versicolor, A. ochraceus, Trichoderma viride, and P. verrucosum var . cyclopium). Commercial antibiotics Streptomycin and Ampicillin and mycotics Ketoconazole and Bifonazole, applied as the positive controls, showed higher antibacterial/antifungal properties for all bacterial and fungal strains. The results of this observation might have a significant impact on the environmental aspects and possible medical purpose in the future.
Wojciech L. Magowski; John C. Moser
The Tarsonemus minimax species-group is established for bark beetle commensals of the genus Tarsonemus Canestrini and Fanzago, 1876. T. minimax Vitzthum 1926 is redescribed, and two new species, T. terebrans and T. typographi n. spp., are described and illustrated. A...
Full Text Available In most lineages, most species have restricted geographic ranges, with only few reaching widespread distributions. How these widespread species reached their current ranges is an intriguing biogeographic and evolutionary question, especially in groups known to be poor dispersers. We reconstructed the biogeographic and temporal origin of the widespread species in a lineage with particularly poor dispersal capabilities, the diving beetle genus Deronectes (Dytiscidae. Most of the ca. 60 described species of Deronectes have narrow ranges in the Mediterranean area, with only four species with widespread European distributions. We sequenced four mitochondrial and two nuclear genes of 297 specimens of 109 different populations covering the entire distribution of the four lineages of Deronectes, including widespread species. Using Bayesian probabilities with an a priori evolutionary rate, we performed (1 a global phylogeny/phylogeography to estimate the relationships of the main lineages within each group and root them, and (2 demographic analyses of the best population coalescent model for each species group, including a reconstruction of the geographical history estimated from the distribution of the sampled localities. We also selected 56 specimens to test for the presence of Wolbachia, a maternally transmitted parasite that can alter the patterns of mtDNA variability. All species of the four studied groups originated in the southern Mediterranean peninsulas and were estimated to be of Pleistocene origin. In three of the four widespread species, the central and northern European populations were nested within those in the northern areas of the Anatolian, Balkan and Iberian peninsulas respectively, suggesting a range expansion at the edge of the southern refugia. In the Mediterranean peninsulas the widespread European species were replaced by vicariant taxa of recent origin. The fourth species (D. moestus was proven to be a composite of unrecognised
García-Vázquez, David; Ribera, Ignacio
In most lineages, most species have restricted geographic ranges, with only few reaching widespread distributions. How these widespread species reached their current ranges is an intriguing biogeographic and evolutionary question, especially in groups known to be poor dispersers. We reconstructed the biogeographic and temporal origin of the widespread species in a lineage with particularly poor dispersal capabilities, the diving beetle genus Deronectes (Dytiscidae). Most of the ca. 60 described species of Deronectes have narrow ranges in the Mediterranean area, with only four species with widespread European distributions. We sequenced four mitochondrial and two nuclear genes of 297 specimens of 109 different populations covering the entire distribution of the four lineages of Deronectes , including widespread species. Using Bayesian probabilities with an a priori evolutionary rate, we performed (1) a global phylogeny/phylogeography to estimate the relationships of the main lineages within each group and root them, and (2) demographic analyses of the best population coalescent model for each species group, including a reconstruction of the geographical history estimated from the distribution of the sampled localities. We also selected 56 specimens to test for the presence of Wolbachia , a maternally transmitted parasite that can alter the patterns of mtDNA variability. All species of the four studied groups originated in the southern Mediterranean peninsulas and were estimated to be of Pleistocene origin. In three of the four widespread species, the central and northern European populations were nested within those in the northern areas of the Anatolian, Balkan and Iberian peninsulas respectively, suggesting a range expansion at the edge of the southern refugia. In the Mediterranean peninsulas the widespread European species were replaced by vicariant taxa of recent origin. The fourth species ( D. moestus ) was proven to be a composite of unrecognised lineages with
David W. Williams; Richard A. Birdsey
This atlas presents maps of historical defoliation by the eastern and western spruce budworms and historical outbreaks of the mountain and southern pine beetles during the past half century. The maps encompass various regions of the conterminous United States and eastern Canada. This publication also serves as documentation for an extended set of digital maps, which...
B. J. Collins; C. C. Rhoades; M. A. Battaglia; R. M. Hubbard
Recent mountain pine beetle infestations have resulted in widespread tree mortality and the accumulation of dead woody fuels across the Rocky Mountain region, creating concerns over future forest stand conditions and fire behavior. We quantified how salvage logging influenced tree regeneration and fuel loads relative to nearby, uncut stands for 24 lodgepole pine...
Peter Biedermann; Kier Klepzig; Taborsky Michael
Fungus cultivation by ambrosia beetles is one of the four independently evolved cases of agriculture known in animals. Such cultivation is most advanced in the highly social subtribe Xyleborina (Scolytinae), which is characterized by haplodiploidy and extreme levels of inbreeding. Despite their ubiquity in forests worldwide, the behavior of these beetles remains poorly...
García-Vázquez, David; Bilton, David T; Foster, Garth N; Ribera, I
Quaternary glacial cycles drove major shifts in both the extent and location of the geographical ranges of many organisms. During glacial maxima, large areas of central and northern Europe were inhospitable to temperate species, and these areas are generally assumed to have been recolonized during interglacials by range expansions from Mediterranean refugia. An alternative is that this recolonization was from non-Mediterranean refugia, in central Europe or western Asia, but data on the origin of widespread central and north European species remain fragmentary, especially for insects. We studied three widely distributed lineages of freshwater beetles (the Platambus maculatus complex, the Hydraena gracilis complex, and the genus Oreodytes), all restricted to running waters and including both narrowly distributed southern endemics and widespread European species, some with distributions spanning the Palearctic. Our main goal was to determine the role of the Pleistocene glaciations in shaping the diversification and current distribution of these lineages. We sequenced four mitochondrial and two nuclear genes in populations drawn from across the ranges of these taxa, and used Bayesian probabilities and Maximum Likelihood to reconstruct their phylogenetic relationships, age and geographical origin. Our results suggest that all extant species in these groups are of Pleistocene origin. In the H. gracilis complex, the widespread European H. gracilis has experienced a rapid, recent range expansion from northern Anatolia, to occupy almost the whole of Europe. However, in the other two groups widespread central and northern European taxa appear to originate from central Asia, rather than the Mediterranean. These widespread species of eastern origin typically have peripherally isolated forms in the southern Mediterranean peninsulas, which may be remnants of earlier expansion-diversification cycles or result from incipient isolation of populations during the most recent Holocene
Sasabe, Masataka; Takami, Yasuoki; Sota, Teiji
Animals with internal fertilization often exhibit marked diversification in genital morphology among closely related species. However, our knowledge of the genetic architecture underlying genital evolution is still limited. We constructed genetic linkage maps and analysed quantitative trait loci (QTL) for F(2) hybrids of two closely related species of the carabid beetles Carabus (Ohomopterus) iwawakianus and C. (O.) maiyasanus, which show matching male and female genital shapes within species, but marked differences in genital morphologies between species. The linkage maps comprised both amplified fragment length polymorphism and microsatellite markers. Composite interval mapping to detect QTL for three traits of male copulatory piece (length, width, weight) and two traits for female vaginal appendix (length, width) resulted in the detection of one to five significant QTL for each trait. The QTL explained large proportions of phenotypic variance. Thus, the interspecific difference in the genital morphologies appeared to be determined by relatively small numbers of genes with large genetic effects. QTL of different traits for the same or different sexes co-occurred on five of eight linkage groups with significant QTL; in particular, three QTL for different male and female genital traits occurred almost at the same position. Each of the male genital traits showed uniform signs of additive genetic effects, suggesting that directional selection has led to species-specific morphologies. However, the signs of additive genetic effects in each female genital trait were not uniform, suggesting that coevolution between sexes is not necessarily concerted. This result requires further assessment because the sample size of F(2) females was small. © 2010 Blackwell Publishing Ltd.
Bosu, Paul P; Miller, Fredric; Wagner, Michael R
We evaluated elm leaf beetle, Pyrhalta luteola (Müller) (Coleoptera: Chrysomelidae), defoliation of 32 elm species or hybrids (taxa) established under field conditions in Holbrook, AZ. Percentage of defoliation, number of eggs, and number of larvae were estimated on randomly selected 15-cm shoot lengths annually in July, from 1996 to 2001. The following nine taxa consistently sustained 15-46% mean overall defoliation: 1) Siberian elm, U. pumila L.; 2) 'Dropmore' elm, U. pumila; 3) 'Camperdownii' elm, U. glabra Huds.; 4) 'Regal' elm, U. glabra x U. carpinifolia Gledisch x U. pumila); 5) 'Sapporo Autumn Gold' elm (U. pumila x U. japonica Sang.); 6) 'New Horizon' elm (U. pumila x U. japonica); 7) 'Charisma' elm [(U. japonica x U. wilsoniana Schneid.) x (U. japonica x U. pumila)]; 8) 'W2115-1' elm (U. parvifolia Jacq. x U. procera Salisb.); and 9) 'Homestead' elm [(U. hollandica Mill. x U. carpinifolia) x (U. pumila-racemosa Dieck x U. carpinifolia)]. Percentage of defoliation was significantly low on four Chinese elm (U. parvifolia) cultivars ('Allee', 'Athena', 'Glory'/lace bark, and 'Kings Choice'). Percentage of defoliation was also low on seven Asian elms (including U. chemnoui Cheng, U. bergmaniana Sneid., U. szechuanica Fang, and species of the U. davidiana Planch. complex [U. davidiana, U. japonica, U. wilsoniana, and U. propinqua Koidz.]) and the American elm (U. americana L.) 'Valley Forge'. Percentage of defoliation and the number of eggs or larvae per plant were highly correlated. The results of this study are generally consistent with results of past laboratory screening trials.
Full Text Available Here we describe two new Hydrovatus species (Coleoptera: Dytiscidae: Hydroporinae: Hydrovatini from the province of Khon Kaen, Isan region in NE Thailand. Hydrovatus is the third most species rich genus of diving beetles (Dytiscidae. It occurs on all continents except Antarctica and now numbers 210 currently recognized species. Both new species, H. diversipunctatus sp. n. and H. globosus sp. n., were collected at lights and are only known from the type locality “Khon Kaen” (a city and province. Diagnoses based on morphology for the separation from closely related species are given together with illustrations of male genitalia and habitus photos. We provide a determination key to Old World species of the pustulatus species group and to Oriental species of the oblongipennis species group.
Cîntă-Pînzaru, Simona; Dehelean, Cristina A; Soica, Codruta; Culea, Monica; Borcan, Florin
Aiming to obtain the highest triterpene content in the extraction products, nine bark samples from the forest abundant flora of Apuseni Mountains, Romania were Raman spectroscopically evaluated. Three different natural extracts from Betula pendula Roth birch bark have been obtained and characterized using Fourier transform vibrational spectra. This study shows that principal components of the birch tree extract can be rapidly recognized and differentiated based on their vibrational fingerprint band shape and intensity. The vibrational spectroscopy results are supported by the GC-MS data. Based on IR and Raman analysis, one can conclude that all the extracts, independent on the solvent(s) used, revealed dominant betulin species, followed by lupeol. Since Raman measurements could also be performed on fresh plant material, we demonstrated the possibility to apply the present results for the prediction of the highest triterpene content in bark species, for the selection of harvesting time or individual genotypes directly in the field, with appropriate portable Raman equipment.
Aanen, D.K.; Slippers, B.; Wingfield, M.J.
Bark beetles are among the most destructive tree pests on the planet. Their symbiosis with fungi has consequently been studied extensively for more than a century. A recent study has identified actinomycete bacteria that are associated with the southern pine beetle and produce specific antibiotics
Burke, Jordan L; Hanula, James L; Horn, Scott; Audley, Jackson P; Gandhi, Kamal J K
Tests were conducted on two insecticides (carbaryl and bifenthrin) for excluding subcortical beetles (Coleoptera: Curculionidae and Cerambycidae) from loblolly pine trees (Pinus taeda L.). Two trap designs (single- and double-pane windows) and two trapping heights (1.5 and 4 m) were also evaluated for maximizing beetle catches. In July 2009, 15 loblolly pine trees were double girdled and were either left unsprayed or sprayed with carbaryl or bifenthrin. A total of 28 473 bark beetles were caught in window traps, including Ips avulsus Eichoff, I. grandicollis (Eichhoff), I. calligraphus (Germar) and Dendroctonus terebrans (Olivier). Both insecticides significantly reduced colonization of the trees by bark and woodboring beetles by 300-400%, with no differences in efficacy observed between the two insecticides. About 59% more I. avulsus were caught in double- than in single-pane window traps, with no differences for any other species. Traps at 4 m caught more I. avulsus and I. grandicollis (290 and 153% respectively), while traps at 1.5 m caught more D. terebrans (215%). Either bifenthrin or carbaryl can be used to exclude subcortical beetles from loblolly pine trees. Trapping data reflect known vertical partitioning on the bole by these insects. Double-pane traps were slightly more effective than single-pane traps in catching subcortical beetles. Copyright © 2012 Society of Chemical Industry.
This thesis describes the distribution, numbers, and morphology of peptidergic neurons and neurosecretory cells in the Colorado potato beetle, as detected with immunocytochemistry with antisera to various regulatory peptides from vertebrates, as well as to the molluscan cardioexcitatory peptide
Rodríguez-Flores, Paula C; Gutiérrez-Rodríguez, Jorge; Aguirre-Ruiz, Ernesto F; García-París, Mario
The tiger beetle assemblage of the wetlands of La Mancha (central Spain) comprises nine species: Calomera littoralis littoralis, Cephalota maura maura, Cephalota circumdata imperialis, Cephalota dulcinea, Cicindela campestris campestris, Cicindela maroccana, Cylindera paludosa, Lophyra flexuosa flexuosa, and Myriochila melancholica melancholica. This assemblage represents the largest concentration of tiger beetles in a single 1º latitude / longitude square in Europe. General patterns of spatial and temporal segregation among species are discussed based on observations of 1462 specimens registered during an observation period of one year, from April to August. The different species of Cicindelini appear to be distributed over space and time, with little overlapping among them. Three sets of species replace each other phenologically as the season goes on. Most of the species occupy drying or dried salt lakes and salt marshes, with sparse vegetation cover. Spatial segregation is marked in terms of substrate and vegetation use. Calomera littoralis and Myriochila melancholica have been observed mainly on wet soils; Cephalota circumdata on dry open saline flats; Cephalota dulcinea and Cylindera paludosa in granulated substrates with typical halophytic vegetation; Cephalota maura is often present in man-modified areas. Cephalota circumdata and Cephalota dulcinea are included as species of special interest in the list of protected species in Castilla-La Mancha. Conservation problems for the Cicindelini assemblage arise from agricultural activities and inadequate use of sport vehicles. Attempts at restoring the original habitat, supressing old semi-industrial structures, may affect the spatial heterogeneity of the lakes, and have an effect on Cicindelinae diversity.
Full Text Available We report on the species richness patterns of epigaeic beetles (Coleoptera: Carabidae and Staphylinidae along a subtropical elevational gradient of Balang Mountain, southwestern China. We tested the roles of environmental factors (e.g. temperature, area and litter cover and direct biotic interactions (e.g. foods and antagonists that shape elevational diversity gradients. Beetles were sampled at 19 sites using pitfall traps along the studied elevational gradient ranging from 1500 m-4000 m during the 2004 growing season. A total of 74416 specimens representing 260 species were recorded. Species richness of epigaeic beetles and two families showed unimodal patterns along the elevational gradient, peaking at mid-elevations (c. 2535 m, and the ranges of most beetle species were narrow along the gradient. The potential correlates of both species richness and environmental variables were examined using linear and second order polynomial regressions. The results showed that temperature, area and litter cover had strong explanatory power of beetle species richness for nearly all richness patterns, of beetles as a whole and of Carabidae and Staphylinidae, but the density of antagonists was associated with species richness of Carabidae only. Multiple regression analyses suggested that the three environmental factors combined contributed most to richness patterns for most taxa. The results suggest that environmental factors associated with temperature, area and habitat heterogeneity could account for most variation in richness pattern of epigaeic beetles. Additionally, the mid-elevation peaks and the small range size of most species indicate that conservation efforts should give attention to the entire gradient rather than just mid-elevations.
Yu, Xiao-Dong; Lü, Liang; Luo, Tian-Hong; Zhou, Hong-Zhang
We report on the species richness patterns of epigaeic beetles (Coleoptera: Carabidae and Staphylinidae) along a subtropical elevational gradient of Balang Mountain, southwestern China. We tested the roles of environmental factors (e.g. temperature, area and litter cover) and direct biotic interactions (e.g. foods and antagonists) that shape elevational diversity gradients. Beetles were sampled at 19 sites using pitfall traps along the studied elevational gradient ranging from 1500 m-4000 m during the 2004 growing season. A total of 74416 specimens representing 260 species were recorded. Species richness of epigaeic beetles and two families showed unimodal patterns along the elevational gradient, peaking at mid-elevations (c. 2535 m), and the ranges of most beetle species were narrow along the gradient. The potential correlates of both species richness and environmental variables were examined using linear and second order polynomial regressions. The results showed that temperature, area and litter cover had strong explanatory power of beetle species richness for nearly all richness patterns, of beetles as a whole and of Carabidae and Staphylinidae, but the density of antagonists was associated with species richness of Carabidae only. Multiple regression analyses suggested that the three environmental factors combined contributed most to richness patterns for most taxa. The results suggest that environmental factors associated with temperature, area and habitat heterogeneity could account for most variation in richness pattern of epigaeic beetles. Additionally, the mid-elevation peaks and the small range size of most species indicate that conservation efforts should give attention to the entire gradient rather than just mid-elevations.
Ohashi, Shinta; Kuroda, Katsushi; Takano, Tsutomu; Suzuki, Youki; Fujiwara, Takeshi; Abe, Hisashi; Kagawa, Akira; Sugiyama, Masaki; Kubojima, Yoshitaka; Zhang, Chunhua; Yamamoto, Koichi
To understand the changes in radiocesium ( 137 Cs) concentrations in stem woods after the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident, we investigated 137 Cs concentrations in the bark, sapwood, heartwood, and whole wood of four major tree species at multiple sites with different levels of radiocesium deposition from the FDNPP accident since 2011 (since 2012 at some sites): Japanese cedar at four sites, hinoki cypress and Japanese konara oak at two sites, and Japanese red pine at one site. Our previous report on 137 Cs concentrations in bark and whole wood samples collected from 2011 to 2015 suggested that temporal variations were different among sites even within the same species. In the present study, we provided data on bark and whole wood samples in 2016 and separately measured 137 Cs concentrations in sapwood and heartwood samples from 2011 to 2016; we further discussed temporal trends in 137 Cs concentrations in each part of tree stems, particularly those in 137 Cs distributions between sapwood and heartwood, in relation to their species and site dependencies. Temporal trends in bark and whole wood samples collected from 2011 to 2016 were consistent with those reported in samples collected from 2011 to 2015. Temporal variations in 137 Cs concentrations in barks showed either a decreasing trend or no clear trend, implying that 137 Cs deposition in barks is inhomogeneous and that decontamination is relatively slow in some cases. Temporal trends in 137 Cs concentrations in sapwood, heartwood, and whole wood were different among species and also among sites within the same species. Relatively common trends within the same species, which were increasing, were observed in cedar heartwood, and in oak sapwood and whole wood. On the other hand, the ratio of 137 Cs concentration in heartwood to that in sapwood (fresh weight basis) was commonly increased to more than 2 in cedar, although distinct temporal trends were not found in the other species, for
Bergeron, J. A. Colin; Spence, John R.; Volney, W. Jan A.
Abstract Spatial associations between species of trees and ground-beetles (Coleoptera: Carabidae) involve many indirect ecological processes, likely reflecting the function of numerous forest ecosystem components. Describing and quantifying these associations at the landscape scale is basic to the development of a surrogate-based framework for biodiversity monitoring and conservation. In this study, we used a systematic sampling grid covering 84 km2 of boreal mixedwood forest to characterize the ground-beetle assemblage associated with each tree species occurring on this landscape. Projecting the distribution of relative basal area of each tree species on the beetle ordination diagram suggests that the carabid community is structured by the same environmental factors that affects the distribution of trees, or perhaps even by trees per se. Interestingly beetle species are associated with tree species of the same rank order of abundance on this landscape, suggesting that conservation of less abundant trees will concomitantly foster conservation of less abundant beetle species. Landscape patterns of association described here are based on characteristics that can be directly linked to provincial forest inventories, providing a basis that is already available for use of tree species as biodiversity surrogates in boreal forest land management. PMID:22371676
Full Text Available Spatial associations between species of trees and ground-beetles (Coleoptera: Carabidae involve many indirect ecological processes, likely reflecting the function of numerous forest ecosystem components. Describing and quantifying these associations at the landscape scale is basic to the development of a surrogate-based framework for biodiversity monitoring and conservation. In this study, we used a systematic sampling grid covering 84 km2 of boreal mixedwood forest to characterize the ground-beetle assemblage associated with each tree species occurring on this landscape. Projecting the distribution of relative basal area of each tree species on the beetle ordination diagram suggests that the carabid community is structured by the same environmental factors that affects the distribution of trees, or perhaps even by trees per se. Interestingly beetle species are associated with tree species of the same rank order of abundance on this landscape, suggesting that conservation of less abundant trees will concomitantly foster conservation of less abundant beetle species. Landscape patterns of association described here are based on characteristics that can be directly linked to provincial forest inventories, providing a basis that is already available for use of tree species as biodiversity surrogates in boreal forest land management.
Full Text Available DNA sequencing techniques used to estimate biodiversity, such as DNA barcoding, may reveal cryptic species. However, disagreements between barcoding and morphological data have already led to controversy. Species delimitation should therefore not be based on mtDNA alone. Here, we explore the use of nDNA and bioclimatic modelling in a new species of aquatic beetle revealed by mtDNA sequence data.The aquatic beetle fauna of Australia is characterised by high degrees of endemism, including local radiations such as the genus Antiporus. Antiporus femoralis was previously considered to exist in two disjunct, but morphologically indistinguishable populations in south-western and south-eastern Australia. We constructed a phylogeny of Antiporus and detected a deep split between these populations. Diagnostic characters from the highly variable nuclear protein encoding arginine kinase gene confirmed the presence of two isolated populations. We then used ecological niche modelling to examine the climatic niche characteristics of the two populations. All results support the status of the two populations as distinct species. We describe the south-western species as Antiporus occidentalis sp.n.In addition to nDNA sequence data and extended use of mitochondrial sequences, ecological niche modelling has great potential for delineating morphologically cryptic species.
Fasola, Taiye R.; Oloyede, Ganiyat Kehinde; Aponjolosun, Babalola S.
Essential oil from the stem bark of Nigerian species of Psidium guajava of the family Myrtaceae was obtained by hydro-distillation using an all-glass Clavenger apparatus. GC and GC/MS analysis were carried out on the essential oil and was found to contain 62 compounds constituting 99.98 % of the total oil composition. The principal constituents are hydrocarbons, amines, amides and esters with 3,6-dioxa-2,4,5,7-tetraoctane,2,2,4,4,5,5,7,7-octamethyl (11.67 %) and cyclononane (10.66 %) dominating the total essential oil. Brine shrimp lethality test was carried out to determine the toxicity of the oils to living organisms (shrimps). LC50 value (µg/ml) of 1.0009 obtained showed that the essential oil of P. guajava stem bark was toxic. The antioxidant property of essential oil was investigated by measuring the decrease in absorption at 517 nm of 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) in a UV/visible spectrophotometer. The oil showed better activity as a radical scavenger than α-tocopherol. The oil activity was 71.83 % at 0.2 mg/ml and the absorption is stoichiometric with respect to the number of electron taken up. Thus, the results of this study showed that the essential oil from P. guajava was not only toxic; it possessed antioxidant activity, which could exert beneficial actions against pathological alterations caused by the presence of highly reactive free radicals. The toxicity of the oil can be taken advantage of in the therapy of diseases involving cell or tumor growth. PMID:27857663
Davydenko, Kateryna; Vasaitis, Rimvydas; Menkis, Audrius
Conifer bark beetles are well known to be associated with fungal complexes, which consist of pathogenic ophiostomatoid fungi as well as obligate saprotroph species. However, there is little information on fungi associated with Ips acuminatus in central and eastern Europe. The aim of the study was to investigate the composition of the fungal communities associated with the pine engraver beetle, I. acuminatus, in the forest-steppe zone in Ukraine and to evaluate the pathogenicity of six associa...
D'Ávila, V A; Aguiar-Menezes, E L; Gonçalves-Esteves, V; Mendonça, C B F; Pereira, R N; Santos, T M
Larvae and adults of certain species of predator lady beetles feed on pollen, guaranteeing their survival, and at times, reproduction in the absence of preferred prey. Palynology, therefore, may contribute in the investigation of botanical families visited by these predators in order to obtain this floral resource. There are records of the visitation of Apiaceae flowers by Coleomegilla maculata DeGeer, 1775 (Coleoptera, Coccinellidae), but not the ingestion of their pollen grains by this lady beetle. The external morphology of pollen grains of three Apiaceae aromatic species (Anethum graveolens L., Coriandrum sativum L., Foeniculum vulgare Mill.) was characterized, and it was evaluated the ingestion of these pollens by fourth instar larvae and adults of C. maculata upon confinement along with flowers of these Apiaceae for 24 and 48 hours. The pollen grains of those species presented similar external morphology. In the two times of exposure, the larvae ingested the same amount of pollen from the three Apiaceae species, and the amount of C. sativum pollen ingested was the same between larvae and adults. The amount of A. graveolens pollen grains ingested by the adults was significantly greater than the pollens of C. sativum and F. vulgare, in 24 hours, with the opposite occurring in 48 hours. In the first 24 hours, the adults ingested more A. graveolens pollen than the larvae, with the opposite occurring with F. vulgare. There was no significant difference in the amount of Apiaceae pollen ingested between larvae and adults in 48 hours. The results suggest that the pollen-eating habits of certain aphidophagous lady beetles may be crucial in their preservation within agro-ecosystems.
Saab, Victoria A.; Latif, Quresh S.; Rowland, Mary M.; Johnson, Tracey N.; Chalfoun, Anna D.; Buskirk, Steven W.; Heyward, Joslin E.; Dresser, Matthew A.
Mountain pine beetle (Dendroctonus ponderosae) (MPB) outbreaks are increasingly prevalent in western North America, causing considerable ecological change in pine (Pinus spp.) forests with important implications for wildlife. We reviewed studies examining wildlife responses to MPB outbreaks and postoutbreak salvage logging to inform forest management and guide future research. Our review included 16 studies describing MPB outbreak relationships with 89 bird species and 6 studies describing relationships with 11 mammalian species, but no studies of reptiles or amphibians. We included studies that compared wildlife response metrics temporally (before versus after the outbreak) and spatially (across sites that varied in severity of outbreak) in relation to beetle outbreaks. Outbreaks ranged in size from 20,600 to ≥107 ha and studies occurred 1‐30 years after the peak MPB outbreak, but most studies were conducted over the short-term (i.e., ≤6 years after the peak of MPB-induced tree mortality). Birds were the only taxa studied frequently; however, high variability existed among those studies to allow many inferences, although some patterns were evident. Avian studies concluded that cavity-nesting species responded more favorably to beetle-killed forests than species with open-cup nests, and species nesting in the shrub layer favored outbreak forests compared with ground and open-cup canopy nesters that generally showed mixed relationships. Bark-drilling species as a group clearly demonstrated a positive short-term association with MPB epidemics compared with that of other foraging assemblages. Cavity-nesting birds that do not consume bark beetles (i.e., secondary cavity-nesting species and nonbark-drilling woodpeckers) also exhibited some positive responses to MPB outbreaks, although not as pronounced or consistent as those of bark-drilling woodpeckers. Mammalian responses to MPB outbreaks were mixed. Studies consistently reported negative effects of MPB
Intensive logging of pine and spruce forests in Estonia has led to a rapid increase in the populations of some insect species. A survey using ground traps baited with a blend of turpentine and ethanol resulted in the recovery of large numbers of the large pine weevil, Hylobius abietis, as well as bark beetles of the genus Hylastes...
Charles A. Triphlehorn; John C. Moser
The genus Cortiecus Piller and Mitterpacher is represented on every continent except Antartica. Blackwelder (1945, p. 533) lists 10 species from Central and South America and Arnett (1963, p. 685) lists 13 from the United States. Most occur with bark beetles (Family Scolytidae), but their roles are poorly understood. Some authors have called them...
Field tests on the efficacy of various scolytid bark beetle pheromones to attract Ips perturbatus (Eichhoff) were conducted from 1977 through 1992 in stands of white spruce (Picea glauca (Moench) Voss) in interior Alaska. Several pheromones attracted high numbers of I. perturbatus and species of the predator Thanasimus to baited funnel traps. Test results also indicated that attacks by I. perturbatus may be deferred by certain semiochemicals.
M.C. Miller; John C. Moser; M. McGregor; J.C. Gregoire; M. Baisier; D.L. Dahlsten; R.A. Werner
Bark beetles of the genus Dendroctonus inflict serious damage in North American coniferous forests. Biological control, which has never been seriously attempted with bark beetles in the United States, should be reconsidered in light of results disclosed here. Impact of indigenous associates is discussed, as well as previous, unsuccessful attempts to...
Christopher J. Fettig; A.Steve Munson; Kenneth E. Gibson
Carbaryl is regarded among the most effective, economically viable, and ecologically-compatible insecticides available for protecting conifers from bark beetle attack in the western United States. Treatments are typically applied in spring prior to initiation of bark beetle flight for that year. We evaluated the efficacy of spring and fall applications for protecting...
Frank, John M.; Massman, William J.; Ewers, Brent E.; Huckaby, Laurie S.; Negrón, José F.
Disturbances are increasing globally due to anthropogenic changes in land use and climate. This study determines whether a disturbance that affects the physiology of individual trees can be used to predict the response of the ecosystem by weighing two competing hypothesis at annual time scales: (a) changes in ecosystem fluxes are proportional to observable patterns of mortality or (b) to explain ecosystem fluxes the physiology of dying trees must also be incorporated. We evaluate these hypotheses by analyzing 6 years of eddy covariance flux data collected throughout the progression of a spruce beetle (Dendroctonus rufipennis) epidemic in a Wyoming Engelmann spruce (Picea engelmannii)-subalpine fir (Abies lasiocarpa) forest and testing for changes in canopy conductance (gc), evapotranspiration (ET), and net ecosystem exchange (NEE) of CO2. We predict from these hypotheses that (a) gc, ET, and NEE all diminish (decrease in absolute magnitude) as trees die or (b) that (1) gc and ET decline as trees are attacked (hydraulic failure from beetle-associated blue-stain fungi) and (2) NEE diminishes both as trees are attacked (restricted gas exchange) and when they die. Ecosystem fluxes declined as the outbreak progressed and the epidemic was best described as two phases: (I) hydraulic failure caused restricted gc, ET (28 ± 4% decline, Bayesian posterior mean ± standard deviation), and gas exchange (NEE diminished 13 ± 6%) and (II) trees died (NEE diminished 51 ± 3% with minimal further change in ET to 36 ± 4%). These results support hypothesis b and suggest that model predictions of ecosystem fluxes following massive disturbances must be modified to account for changes in tree physiological controls and not simply observed mortality.
Several species of plants and animals live on trees. The diversity ranges from microscopic bacteria to large mammals. Only the bark of woody plants can harbour smaller creatures and tiny plants. A plant species growing on other plants is technically termed as epiphyte or aerophyte. Many sub-aerial algae inhabiting tree ...
Fischer, A.; Fischer, H. S.; Kopecký, Martin; Macek, Martin; Wild, Jan
Roč. 45, č. 9 (2015), s. 1164-1171 ISSN 0045-5067 R&D Projects: GA ČR GAP504/10/0843 Institutional support: RVO:67985939 Keywords : disturbance * permanent plot * multiple-site dissimilarity Subject RIV: GK - Forestry Impact factor: 1.682, year: 2015
Jonášová, Magda; Prach, Karel
Roč. 23, č. 1 (2004), s. 15-27 ISSN 0925-8574 Institutional research plan: CEZ:AV0Z6087904 Keywords : forest management * mountain spruce forest * natural regeneration Subject RIV: GK - Forestry Impact factor: 0.890, year: 2004 http://www.sciencedirect.com
Yuri Baranchikov; Evgeniy Akulov; Sergey. Astapenko
Polygraphus proximus Brandford (Coleoptera: Scolytidae) is a common feeder on Far Eastern firs: Abies nephrolepis, A. hollophyll, and A. sachalinensis. Its native range occupies northeastern China, Korea, Japan, Kurile and Sakhalin Islands, and the southern part of the Russian Far East (Primorskiy and...
The flea beetle genus Meishania Chen & Wang is revised and five new species - M. cangshanensis sp. nov., M. flavipennis sp. nov., M. fulvotigera sp. nov., and M. sichuanica sp. nov. from China and M. bhutanensis sp. nov. from Bhutan - are described. All species of Meishania are illustrated and a key...
Krell, Frank-Thorsten; Dimitrov, Dimitar
Despite the increasing rate of systematic research on scarabaeine dung beetles (Coleoptera: Scarabaeidae: Scarabaeinae), their fossil record has remained largely unrevised. In this paper, we review all 33 named scarabaeine fossils and describe two new species from Dominican amber (Canthochilum alleni sp.n., Canthochilum philipsivieorum sp.n.). We provide a catalogue of all fossil Scarabaeinae and evaluate their assignment to this subfamily, based primarily on the original descriptions but also, where possible, by examining the type specimens. We suggest that only 21 fossil taxa can be reliably assigned to the Scarabaeinae, while the remaining 14 should be treated as doubtful Scarabaeinae. The doubtful scarabaeines include the two oldest dung beetle fossils known from the Cretaceous and we suggest excluding them from any assessments of the minimum age of scarabaeine dung beetles. The earliest reliably described scarabaeine fossil appears to be Lobateuchus parisii, known from Oise amber (France), which shifts the minimum age of the Scarabaeinae to the Eocene (53 Ma). We scored the best-preserved fossils, namely Lobateuchus and the two Canthochilum species described herein, into the character matrix used in a recent morphology-based study of dung beetles, and then inferred their phylogenetic relationships with Bayesian and parsimony methods. All analyses yielded consistent phylogenies where the two fossil Canthochilum are placed in a clade with the extant species of Canthochilum, and Lobateuchus is recovered in a clade with the extant genera Ateuchus and Aphengium. Additionally, we evaluated the distribution of dung beetle fossils in the light of current global dung beetle phylogenetic hypotheses, geological time and biogeography. The presence of only extant genera in the late Oligocene and all later records suggests that the main present-day dung beetle lineages had already been established by the late Oligocene–mid Miocene. PMID:27547512
Tarasov, Sergei; Vaz-de-Mello, Fernando Z; Krell, Frank-Thorsten; Dimitrov, Dimitar
Despite the increasing rate of systematic research on scarabaeine dung beetles (Coleoptera: Scarabaeidae: Scarabaeinae), their fossil record has remained largely unrevised. In this paper, we review all 33 named scarabaeine fossils and describe two new species from Dominican amber (Canthochilum alleni sp.n., Canthochilum philipsivieorum sp.n.). We provide a catalogue of all fossil Scarabaeinae and evaluate their assignment to this subfamily, based primarily on the original descriptions but also, where possible, by examining the type specimens. We suggest that only 21 fossil taxa can be reliably assigned to the Scarabaeinae, while the remaining 14 should be treated as doubtful Scarabaeinae. The doubtful scarabaeines include the two oldest dung beetle fossils known from the Cretaceous and we suggest excluding them from any assessments of the minimum age of scarabaeine dung beetles. The earliest reliably described scarabaeine fossil appears to be Lobateuchus parisii, known from Oise amber (France), which shifts the minimum age of the Scarabaeinae to the Eocene (53 Ma). We scored the best-preserved fossils, namely Lobateuchus and the two Canthochilum species described herein, into the character matrix used in a recent morphology-based study of dung beetles, and then inferred their phylogenetic relationships with Bayesian and parsimony methods. All analyses yielded consistent phylogenies where the two fossil Canthochilum are placed in a clade with the extant species of Canthochilum, and Lobateuchus is recovered in a clade with the extant genera Ateuchus and Aphengium. Additionally, we evaluated the distribution of dung beetle fossils in the light of current global dung beetle phylogenetic hypotheses, geological time and biogeography. The presence of only extant genera in the late Oligocene and all later records suggests that the main present-day dung beetle lineages had already been established by the late Oligocene-mid Miocene.
Full Text Available Despite the increasing rate of systematic research on scarabaeine dung beetles (Coleoptera: Scarabaeidae: Scarabaeinae, their fossil record has remained largely unrevised. In this paper, we review all 33 named scarabaeine fossils and describe two new species from Dominican amber (Canthochilum alleni sp.n., Canthochilum philipsivieorum sp.n.. We provide a catalogue of all fossil Scarabaeinae and evaluate their assignment to this subfamily, based primarily on the original descriptions but also, where possible, by examining the type specimens. We suggest that only 21 fossil taxa can be reliably assigned to the Scarabaeinae, while the remaining 14 should be treated as doubtful Scarabaeinae. The doubtful scarabaeines include the two oldest dung beetle fossils known from the Cretaceous and we suggest excluding them from any assessments of the minimum age of scarabaeine dung beetles. The earliest reliably described scarabaeine fossil appears to be Lobateuchus parisii, known from Oise amber (France, which shifts the minimum age of the Scarabaeinae to the Eocene (53 Ma. We scored the best-preserved fossils, namely Lobateuchus and the two Canthochilum species described herein, into the character matrix used in a recent morphology-based study of dung beetles, and then inferred their phylogenetic relationships with Bayesian and parsimony methods. All analyses yielded consistent phylogenies where the two fossil Canthochilum are placed in a clade with the extant species of Canthochilum, and Lobateuchus is recovered in a clade with the extant genera Ateuchus and Aphengium. Additionally, we evaluated the distribution of dung beetle fossils in the light of current global dung beetle phylogenetic hypotheses, geological time and biogeography. The presence of only extant genera in the late Oligocene and all later records suggests that the main present-day dung beetle lineages had already been established by the late Oligocene–mid Miocene.
Piñero, Jaime C
Spotted (Diabrotica undecimpunctata howardii) and striped (Acalymma vittatum) cucumber beetles (Coleoptera: Chrysomelidae) are serious pests of field-grown cucurbits in most areas of the United States where these crops are grown. This study aimed at quantifying, using a comparative approach, the behavioral response of A. vittatum and D. u. howardii to visual and olfactory cues associated with different trap types. In a first field study, Pherocon corn rootworm (CRW) traps baited with a 5-component floral-based lure (= AgBio lure) captured significantly more A. vittatum than traps baited with any other commercial lure. When used in combination with yellow sticky cards, the AgBio lure outperformed the other lures except for the Trécé lure TRE8274. Subsequent tests revealed that the response of both cucumber beetle species to the AgBio lure was positively associated with increases in the amount of lure used. In the last series of tests that involved color discrimination by the beetles, traps constructed using 3.8-liter jugs painted yellow outperformed the CRW trap. Results from on-farm research, conducted at a commercial vegetable farm, confirmed the beetles' visual preference for yellow, and also revealed an excellent performance of the mass trapping system, which kept cucumber beetle densities in the cash crop below economic thresholds. Combined findings indicate that the mass trapping system developed can be implemented as part of a broader IPM program aimed at managing cucumber beetles.
Saremba, Brett M; Tymm, Fiona J M; Baethke, Kathy; Rheault, Mark R; Sherif, Sherif M; Saxena, Praveen K; Murch, Susan J
American Elms were devastated by an outbreak of Dutch Elm Disease is caused by the fungus Ophiostoma novo-ulmi Brasier that originated in Asia and arrived in the early 1900s. In spite of decades of study, the specific mechanisms and disease resistance in some trees is not well understood. the fungus is spread by several species of bark beetles in the genus Scolytus, during their dispersal and feeding. Our objective was to understand elm responses to beetle feeding in the absence of the fungus to identify potential resistance mechanisms. A colony of Scolytus multistriatus was established from wild-caught beetles and beetles were co-incubated with susceptible or resistant American elm varieties in a controlled environment chamber. Beetles burrowed into the auxillary meristems of the young elm shoots. The trees responded to the beetle damage by a series of spikes in the concentration of plant growth regulating compounds, melatonin, serotonin, and jasmonic acid. Spikes in melatonin and serotonin represented a 7,000-fold increase over resting levels. Spikes in jasmonic acid were about 10-fold higher than resting levels with one very large spike observed. Differences were noted between susceptible and resistant elms that provide new understanding of plant defenses.
Full Text Available Communities of epigeic beetles were studied using pitfall trapping on 10 plots with the different stage of decline and clear-cut plots without coarse woody debris. Species richness (number of all species, S, total species diversity as the Shannon-Wiener’s index (H and equitability (e were calculated in the DBreleve. The Ward’s method of hierarchical agglomerative classification with Euclidean distance was used for the differentiation of the communities on the plots. Species data for this analyse were represented by logarithm-transformed activities [log(x+1]. The single-factor analysis of variance (ANOVA was used for statistical testing of differences in structural parameters (e.g. species richness and diversity amongst distinguished groups of the plots. The species diversity and activity differs on glades without trees and coarse woody debris. The highest number of species was found in clear-cut areas. The lowest number of species was found on the plots with the living forest particularly invaded by bark beetle. This fact is caused by the fact that the clear-cut plots are invaded by ubiquitous and anthropotolerant species with good migration possibilities. These species are adapted to habitats without trees and are able to leave even in the habitats with very sparse or without vegetation. Species living in the forest even under the bark beetle attack are often stenotopic and adapted to the forest microclimate (higher humidity and low average temperature. These species are very sensitive to great difference in the daily changes of microclimate. The study of beetle communities support the hypothesis that the keeping of dead tree stands on plots after bark beetle outbreak is better for biodiversity conservation than the cutting down of trees and the abolishment of stems.
Kuroda, Katsushi; Kagawa, Akira; Tonosaki, Mario
Radiocesium ((134)Cs and (137)Cs) distribution in tree stems of Japanese cedar (aged 40-56 y), red pine (42 y), and oak (42 y) grown in Fukushima Prefecture were investigated approximately half a year after the Fukushima Dai-ichi nuclear accident. Japanese cedar, red pine, and oak were selected from five sites, one site, and one site, respectively. Three trees at each site were felled, and bark, sapwood (the outer layer of wood in the stem), and heartwood (the inner layer of wood in the stem) separately collected to study radiocesium concentrations measured by gamma-ray spectrometry. The radiocesium deposition densities at the five sites were within the range of 16-1020 kBq m(-2). The radiocesium was distributed in bark, sapwood, and heartwood in three tree species, indicating that very rapid translocation of radiocesium into the wood. The concentration of radiocesium in oak (deciduous angiosperm) bark was higher than that in the bark of Japanese cedar and red pine (evergreen gymnosperms). Both sapwood and heartwood contained radiocesium, and the values were much lower than that in the bark samples. The results suggest that radiocesium contamination half a year after the accident was mainly attributable to the direct radioactive deposition. The radiocesium concentrations in the Japanese cedar samples taken from five sites rose with the density of radiocesium accumulation on the ground surface. To predict the future dynamics of radiocesium in tree stems, the present results taken half a year after the accident are important, and continuous study of radiocesium in tree stems is necessary. Copyright © 2013 Elsevier Ltd. All rights reserved.
Rosenberger, Derek W; Venette, Robert C; Maddox, Mitchell P; Aukema, Brian H
As climates change, thermal limits may no longer constrain some native herbivores within their historical ranges. The mountain pine beetle, Dendroctonus ponderosae Hopkins, is a tree-killing bark beetle native to western North America that is currently expanding its range. Continued eastward expansion through the newly invaded and novel jack pine (Pinus banksiana Lamb.) trees of the Canadian boreal forest could result in exposure of several species of novel potential host pines common in northeastern North America to this oligophagous herbivore. Due to the tightly co-evolved relationship between mountain pine beetle and western pine hosts, in which the insect utilizes the defensive chemistry of the host to stimulate mass attacks, we hypothesized that lack of co-evolutionary association would affect the host attraction and acceptance behaviors of this insect among novel hosts, particularly those with little known historical association with an aggressive stem-infesting insect. We studied how beetle behavior differed among the various stages of colonization on newly cut logs of four novel potential pine host species; jack, red (P. resinosa Ait.), eastern white (P. strobus L.) and Scots (P. sylvestris L.) pines, as well as two historical hosts, ponderosa (P. ponderosa Dougl. ex. Laws. var. scopulorum Engelm.) and lodgepole (P. contorta Dougl. var. latifolia Engelm.) pines. Overall, we found that beetle colonization behaviors at each stage in the colonization process differ between pine hosts, likely due to differing chemical and physical bark traits. Pines without co-evolved constitutive defenses against mountain pine beetle exhibited reduced amounts of defensive monoterpenoid chemicals; however, such patterns also reduced beetle attraction and colonization. Neither chemical nor physical defenses fully defended trees against the various stages of host procurement that can result in tree colonization and death.
Villari, Caterina; Battisti, Andrea; Chakraborty, Sourav; Michelozzi, Marco; Bonello, Pierluigi; Faccoli, Massimo
Conifer bark beetles are often associated with fungal complexes whose components have different ecological roles. Some associated species are nutritionally obligate fungi, serving as nourishment to the larvae, whereas others are pathogenic blue-stain fungi known to be involved in the interaction with host defenses. In this study we characterized the local and systemic defense responses of Scots pine (Pinus sylvestris L.) against Ophiostoma brunneo-ciliatum Math. (a blue-stain pathogen) and Hyalorhinocladiella macrospora (Franke-Grosm.) Harr. (a nutritional fungus). These fungi are the principal associates of the pine engraver beetle, Ips acuminatus (Gyll.). Host responses were studied following inoculation with the fungi, singly and as a fungal complex, and by identifying and quantifying terpenoids, phenolic compounds and lignin. Although the length of the necrotic lesions differed between control (wound) and fungal treatments, only two compounds (pinosylvin monomethyl ether and (+)-α-pinene) were significantly affected by the presence of the fungi, indicating that Scots pine has a generic, rather than specific, induced response. The fact that both nutritional and blue-stain fungi triggered comparable induced defense responses suggests that even a non-pathogenic fungus may participate in exhausting host plant defenses, indirectly assisting in the beetle establishment process. Our findings contribute to the further development of current theory on the role of associated fungal complexes in bark beetle ecology.
Timothy T. Work; Deborah G. McCullough; William J. Mattson
More than 12,300 moths and 2,500 carabid beetles were trapped during 3 years (1993 through 1995) in two different ecological land type phases (ELTP's) in the Huron-Manistee National Forest in Michigan. One ELTP (no. 20) was dominated by oaks, and the other (no. 45) was dominated by sugar maple; each had distinctive kinds of insects, in spite of the fact that many...
Hambäck, Peter A; Weingartner, Elisabet; Ericson, Lars; Fors, Lisa; Cassel-Lundhagen, Anna; Stenberg, Johan A; Bergsten, Johannes
To understand the ecological and evolutionary consequences of species interactions in food webs necessitates that interactions are properly identified. Genetic analyses suggest that many supposedly generalist parasitoid species should rather be defined as multiple species with a more narrow diet, reducing the probability that such species may mediate indirect interactions such as apparent competition among hosts. Recent studies showed that the parasitoid Asecodes lucens mediate apparent competition between two hosts, Galerucella tenella and G. calmariensis, affecting both interaction strengths and evolutionary feedbacks. The same parasitoid was also recorded from other species in the genus Galerucella, suggesting that similar indirect effects may also occur for other species pairs. To explore the possibility of such interactions, we sequenced mitochondrial and nuclear genetic markers to resolve the phylogeny of both host and parasitoid and to test the number of parasitoid species involved. We thus collected 139 Galerucella larvae from 8 host plant species and sequenced 31 adult beetle and 108 parasitoid individuals. The analysis of the Galerucella data, that also included sequences from previous studies, verified the five species previously documented as reciprocally monophyletic, but the Bayesian species delimitation for A. lucens suggested 3-4 cryptic taxa with a more specialised host use than previously suggested. The gene data analyzed under the multispecies coalescent model allowed us to reconstruct the species tree phylogeny for both host and parasitoid and we found a fully congruent coevolutionary pattern suggesting that parasitoid speciation followed upon host speciation. Using multilocus sequence data in a Bayesian species delimitation analysis we propose that hymenopteran parasitoids of the genus Asecodes that infest Galerucella larvae constitute at least three species with narrow diet breath. The evolution of parasitoid Asecodes and host Galerucella show
Full Text Available Abstract Background Aiming to obtain the highest triterpene content in the extraction products, nine bark samples from the forest abundant flora of Apuseni Mountains, Romania were Raman spectroscopically evaluated. Three different natural extracts from Betula pendula Roth birch bark have been obtained and characterized using Fourier transform vibrational spectra. Results This study shows that principal components of the birch tree extract can be rapidly recognized and differentiated based on their vibrational fingerprint band shape and intensity. The vibrational spectroscopy results are supported by the GC-MS data. Based on IR and Raman analysis, one can conclude that all the extracts, independent on the solvent(s used, revealed dominant betulin species, followed by lupeol. Conclusions Since Raman measurements could also be performed on fresh plant material, we demonstrated the possibility to apply the present results for the prediction of the highest triterpene content in bark species, for the selection of harvesting time or individual genotypes directly in the field, with appropriate portable Raman equipment.
Kier D. Klepzig; J. Flores-Otero; R.W. Hofstetter; M.P. Ayers
Competitive interactions among bark beetle associated fungi are potentially influenced by abiotic factors. Water potential, in particular, undergoes marked changes over the course of beetle colonization of tree hosts. To investigate the impact of water potential on competition among three southern pine beetle associated fungi, Ophiostoma minus,
Ploetz, Randy C; Konkol, Joshua L; Narvaez, Teresa; Duncan, Rita E; Saucedo, Ramon J; Campbell, Alina; Mantilla, Julio; Carrillo, Daniel; Kendra, Paul E
We summarize the information available on ambrosia beetle species that have been associated in Florida with Raffaelea lauricola T.C. Harr., Fraedrich & Aghayeva, the primary symbiont of Xyleborus glabratus Eichhoff and cause of laurel wilt. In total, 14 species in Ambrosiodmus, Euwallacea, Premnobius, Xyleborus, Xyleborinus, and Xylosandrus were either reared from laurel wilt-affected host trees or trapped in laurel wilt-affected stands of the same, and assayed for R. lauricola. In six collections from native species in the southeastern United States [Persea borbonia (L.), Persea palustris (Raf.) Sarg., and Persea humilis Nash] and four from avocado (Persea americana Mill.), extracted mycangia or heads (taxa with mandibular mycangia) or intact bodies (taxa with mycangia in other locations) were surface-disinfested before assays on a semi-selective medium for the isolation of Raffaelea (CSMA+). Raffaelea lauricola was identified based on its characteristic phenotype on CSMA+, and the identity of a random subset of isolates was confirmed with taxon-specific microsatellite markers. The pathogen was recovered from 34% (246 of 726) of the individuals that were associated with the native Persea spp., but only 6% (58 of 931) of those that were associated with avocado. Over all studies, R. lauricola was recovered from 10 of the ambrosia beetle species, but it was most prevalent in Xyleborus congeners. This is the first record of R. lauricola in Ambrosiodmus lecontei Hopkins, Xyleborinus andrewesi (Blandford), and Xyleborus bispinatus Eichhoff. The potential effects of R. lauricola's promiscuity are discussed. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: firstname.lastname@example.org.
Paradise, C J; Dunson, William A
The insect community living in central Pennsylvania treeholes in autumn consists primarily of larvae of two species of helodid beetles, Prionocyphon discoideus and Helodes pulchella, and larvae of one species of ceratopogonid midge,Culicoides guttipennis. We manipulated treehole volume and the densities of these insects in laboratory microcosms. We hypothesized that: (1) helodid beetle larvae, which are shredders, would enhance growth and survival of ceratopogonid midge larvae (deposit feeders) in a processing chain commensalism, and (2) the quantity of resources expressed as water volume plus leaf litter would affect helodids and protozoans directly. Intraspecific competition was not found in midges, nor was interspecific competition between the two helodid species. Protozoan population densities decreased or grew slower in the presence of insects and in smaller microcosms. Development time and adult wing length of the midge (C. guttipennis) were affected by both total microcosm volume and insect species combination. Under resource limitation, midges grew larger in the presence of helodids, and in general, midges were larger in treatments with higher ratios of helodids to midges. Water chemistry in the microcosms was affected both temporally and by insect presence. Hydrogen ion levels decreased over time, and microcosms with no insects had lower hydrogen ion levels. Specific conductance increased in all treatments over time, and microcosms with no insects had lower conductivity than most treatments. Helodid larvae have a positive effect on midges, possibly due to a processing chain facilitation. If helodids are keystone decomposers in this system, their presence could affect resource availability and affect other organisms in the community. Similar processing chain commensalisms occur in other phytotelmata. These types of interactions may therefore be important in the structure and function of detritus-based communities.
... willow bark extract, ginger root concentrate, boswellia extract, turmeric root extract, cayenne, and hyaluronic acid (Instaflex Joint ... Sensitivity to aspirin: People with ASTHMA, STOMACH ULCERS, DIABETES, GOUT, HEMOPHILIA, HYPOPROTHROMBINEMIA, or KIDNEY or LIVER DISEASE ...
Schoville, Sean D; Chen, Yolanda H; Andersson, Martin N; Benoit, Joshua B; Bhandari, Anita; Bowsher, Julia H; Brevik, Kristian; Cappelle, Kaat; Chen, Mei-Ju M; Childers, Anna K; Childers, Christopher; Christiaens, Olivier; Clements, Justin; Didion, Elise M; Elpidina, Elena N; Engsontia, Patamarerk; Friedrich, Markus; García-Robles, Inmaculada; Gibbs, Richard A; Goswami, Chandan; Grapputo, Alessandro; Gruden, Kristina; Grynberg, Marcin; Henrissat, Bernard; Jennings, Emily C; Jones, Jeffery W; Kalsi, Megha; Khan, Sher A; Kumar, Abhishek; Li, Fei; Lombard, Vincent; Ma, Xingzhou; Martynov, Alexander; Miller, Nicholas J; Mitchell, Robert F; Munoz-Torres, Monica; Muszewska, Anna; Oppert, Brenda; Palli, Subba Reddy; Panfilio, Kristen A; Pauchet, Yannick; Perkin, Lindsey C; Petek, Marko; Poelchau, Monica F; Record, Éric; Rinehart, Joseph P; Robertson, Hugh M; Rosendale, Andrew J; Ruiz-Arroyo, Victor M; Smagghe, Guy; Szendrei, Zsofia; Thomas, Gregg W C; Torson, Alex S; Vargas Jentzsch, Iris M; Weirauch, Matthew T; Yates, Ashley D; Yocum, George D; Yoon, June-Sun; Richards, Stephen
The Colorado potato beetle is one of the most challenging agricultural pests to manage. It has shown a spectacular ability to adapt to a variety of solanaceaeous plants and variable climates during its global invasion, and, notably, to rapidly evolve insecticide resistance. To examine evidence of rapid evolutionary change, and to understand the genetic basis of herbivory and insecticide resistance, we tested for structural and functional genomic changes relative to other arthropod species using genome sequencing, transcriptomics, and community annotation. Two factors that might facilitate rapid evolutionary change include transposable elements, which comprise at least 17% of the genome and are rapidly evolving compared to other Coleoptera, and high levels of nucleotide diversity in rapidly growing pest populations. Adaptations to plant feeding are evident in gene expansions and differential expression of digestive enzymes in gut tissues, as well as expansions of gustatory receptors for bitter tasting. Surprisingly, the suite of genes involved in insecticide resistance is similar to other beetles. Finally, duplications in the RNAi pathway might explain why Leptinotarsa decemlineata has high sensitivity to dsRNA. The L. decemlineata genome provides opportunities to investigate a broad range of phenotypes and to develop sustainable methods to control this widely successful pest.
Full Text Available Experimental research on beetle responses to removal of logging residues following clearcut harvesting in the boreal balsam fir forest of Quebec revealed several abundant rove beetle (Staphylinidae species potentially important for long-term monitoring. To understand the trophic affiliations of these species in forest ecosystems, it was necessary to analyze their gut contents. We used microscopic and molecular (DNA methods to identify the gut contents of the following rove beetles: Atheta capsularis Klimaszewski, Atheta klagesi Bernhauer, Oxypoda grandipennis (Casey, Bryophacis smetanai Campbell, Ischnosoma longicorne (Mäklin, Mycetoporus montanus Luze, Tachinus frigidus Erichson, Tachinus fumipennis (Say, Tachinus quebecensis Robert, and Pseudopsis subulata Herman. We found no apparent arthropod fragments within the guts; however, a number of fungi were identified by DNA sequences, including filamentous fungi and budding yeasts [Ascomycota: Candida derodonti Suh & Blackwell (accession number FJ623605, Candida mesenterica (Geiger Diddens & Lodder (accession number FM178362, Candida railenensis Ramirez and Gonzáles (accession number JX455763, Candida sophie-reginae Ramirez & González (accession number HQ652073, Candida sp. (accession number AY498864, Pichia delftensis Beech (accession number AY923246, Pichia membranifaciens Hansen (accession number JQ26345, Pichia misumaiensis Y. Sasaki and Tak. Yoshida ex Kurtzman 2000 (accession number U73581, Pichia sp. (accession number AM261630, Cladosporium sp. (accession number KF367501, Acremonium psammosporum W. Gams (accession number GU566287, Alternaria sp. (accession number GU584946, Aspergillus versicolor Bubak (accession number AJ937750, and Aspergillus amstelodami (L. Mangin Thom and Church (accession number HQ728257]. In addition, two species of bacteria [Bradyrhizobium japonicum (KirchnerJordan (accession number BA000040 and Serratia marcescens Bizio accession number CP003942] were found in
Kier D. Klepzig; J.C. Moser; F.J. Lombardero; R.W. Hofstetter; M.P. Ayres
Symbioses among bark beetles and their fungal and mite associates involve complex, multi-level interactions. Dendroctonus frontalis attacks and kills southern pines, introducing fungi into the tree. Ophiostoma minus may initially aid beetles in killing trees, but later this "bluestain" fungus becomes an antagonist,...
Freitag, R.; Hastings, L.; Mercer, W.R.; Smith, A.
Twenty species of ground beetles (Family Carabidae) and one species of carrion beetle (Family Silphidae) were collected in six stations east of a kraft paper mill in Thunder Bay, Ontario, from May to August, 1971. The beetle population decreased markedly towards the mill. There was no apparent statistical difference in size variation of specimens near the mill and those further away.