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.
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...
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 ...
Jian-Ting Fan; Daniel Miller; Long-Wa Zhang; Jiang-Hua Sun
We evaluated the attraction of Monochamus alternatus Hope (Coleoptera: Cerambycidae), Dryocoetes luteus Blandford and Orthotomicus erosusWollaston (Coleoptera: Curculionidae: Scolytinae) to multiple-funnel traps baited with the pine volatiles, ethanol and (+)-Î±-pinene and the bark beetle pheromones, ipsenol and ipsdienol. M. alternatus were attracted to traps baited...
Etxebeste, Iñaki; Lencina, José L; Pajares, Juan
Some bark beetle species (Coleoptera: Scolytinae) produce aggregation pheromones that allow coordinated attack on their conifer hosts. As a new saproxylic habitat is founded, an assemblage of associated beetles kairomonally respond to bark beetle infochemicals. Ips sexdentatus is one of the major damaging insects of Pinus spp. in Southern Europe. Its response to varying ipsenol (Ie) percentages in relation to ipsdienol (Id) was studied in northwestern Spain, along with the entire saproxylic beetle assemblage captured at multiple-funnel traps. Response profile modeling was undertaken for I. sexdentatus sexes and sex-ratios, associated species and for selected trophic groups using a reference Gaussian model. In addition, the effects on the saproxylic assemblages were analyzed. I. sexdentatus response curve peaked at 22.7% Ie content, while remaining taxa that could be modeled, peaked above ca. 40% Ie. Predator guilds showed a linear relationship with Ie proportion, while competitors showed a delayed response peak. Consequently, species assemblages differed markedly between varying pheromone component mixtures. Given that the evaluated pheromonal proportions mimicked that of logs being colonized by I. sexdentatus, results suggested that the registered differential responses at different levels might provide I. sexdentatus with a temporal window that maximizes conspecific attraction while reducing interference with competitor and predatory guilds. Described responses might help improve the monitoring of the population status of target bark beetles and their associates, but also point toward the by-catch of many natural enemies, as well as rare saproxylic beetle species, interfering with the aims of sustainable forest management.
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.
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...
Taft, Spencer; Najar, Ahmed; Erbilgin, Nadir
The secondary chemistry of host plants can have cascading impacts on the establishment of new insect herbivore populations, their long-term population dynamics, and their invasion potential in novel habitats. Mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae) has recently expanded its range into forests of jack pine, Pinus banksiana Lamb., in western Canada. We investigated whether variations in jack pine monoterpenes affect beetle pheromone production, as the primary components of the beetle's aggregation pheromone, (-)-trans-verbenol and anti-aggregation pheromone (-)-verbenone, are biosynthesized from the host monoterpene α-pinene. Jack pine bolts were collected from five Canadian provinces east of the beetle's current range, live D. ponderosae were introduced into them, and their monoterpene compositions were characterized. Production of (-)-trans-verbenol and (-)-verbenone emitted by beetles was measured to determine whether pheromone production varies with monoterpene composition of jack pines. Depending on particular ratios of major monoterpenes in host phloem, jack pine could be classified into three monoterpenoid groups characterized by high amounts of (+)-α-pinene, 3-carene, or a more moderate blend of monoterpenes, and beetle pheromone production varied among these groups. Specifically, beetles reared in trees characterized by high (+)-α-pinene produced the most (-)-trans-verbenol and (-)-verbenone, while beetles in trees characterized by high 3-carene produced the least. Our results indicate that pheromone production by D. ponderosae will remain a significant aspect and important predictor of its survival and persistence in the boreal forest.
Alicia Nino-Dominguez; Brian T. Sullivan; Jose H. Lopez-Urbina; Jorge E. Macias-Samano
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...
Brian Sullivan; Kenji Mori
Flight responses of the southern pine beetle, Dendroctonus frontalis Zimmermann, to widely-spaced (>130 m) traps baited with pine volatiles (in turpentine) and the female-produced pheromone component frontalin were enhanced when a bait containing the male pheromone component (+)-endo-brevicomin was attached...
Wind calamity in a volume of approximately 7600 m 3 of wood took place in nature reserve (NR) Fabova hola in November 2004. Another calamity of approximately the same scale (7600 m 3 ) occurred in a storm from 23 to 24 August 2007. Then a bark beetle gradation began in NR. The aim of this work is to evaluate development of beetle populations on the basis of trapping into pheromone traps in NR Fabova hola and in its protection zone made in the years 2006 to 2009 focusing on the spruce bark beetle (Ips typographus) and on comparison of average year-round trapping in three different groups of traps depending on their position - in the calamity of 2004, in recently opened site wall (the violated site wall), and the wind unspoiled site wall (while serving as a control surface). Obtained results are discussed.
Monitoring of spruce bark beetle in nature reserve Fabova hola Mountain in the Slovenske Rudohorie Mountains at an altitude of 1.100-1.440 meters was conducted from 2006 to 2009. Slovenske Rudohorie Mountains was affected by two windstorms (2004 and 2007) followed by a gradation of bark beetles. This article has examined the dependence between amount of solar radiation and trapping of spruce bark beetle into pheromone traps.
Daniel R. Miller; John H. Borden; B. Staffan Lindgren
Verbenone significantly reduced catches of Ips latidens (LeConte), I. pini (Say), and Dendroctonus ponderosae Hopkins in multiple-funnel traps, baited with aggregation pheromones, in stands of lodgepole pine in southern British Columbia. Interruption of attraction was dose dependent for all three species. There...
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...
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,...
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...
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
Daniel R. Miller; John H. Borden
Monoterpenes affected the attraction of three sympatric species of bark beetles (Coleoptera: Scolytidae) to pheromone-baited multiple-funnel traps in stands of lodgepole pine. Catches of Ips pini(Say) in traps baited with its pheromone, ipsdienol, were directly related to the release rates of 3-carene, Ã-pphellandrene, and Ã-pinene. Catches of
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...
Gaylord, M L; Hofstetter, R W; Wagner, M R
Our research used a combination of passive traps, funnel traps with lures, baited trees, and surveys of long-term thinning plots to assess the impacts of different levels of stand basal area (BA) on bark beetle tree attack and on trap captures of Ips spp., Dendroctonus spp., and their predators. The study occurred at two sites in ponderosa pine, Pinus ponderosa Dougl. ex Laws., forests, from 2004 to 2007 during low bark beetle populations. Residual stand BA ranged from 9.0 to 37.0 m2/ha. More predators and bark beetles were collected in passive traps in stands of lower BA than in stands of higher BA; however, significance varied by species and site, and total number of beetles collected was low. Height of the clear panel passive traps affected trap catches for some species at some sites and years. When pheromone lures were used with funnel traps [Ips pini (Say) lure: lanierone, +03/-97 ipsdienol], we found no significant difference in trap catches among basal area treatments for bark beetles and their predators. Similarly, when trees were baited (Dendroctonus brevicomis LeConte lure: myrcene, exo-brevicomin and frontalin), we found no significant difference for days to first bark beetle attack. Surveys of long-term thinning treatments found evidence of bark beetle attacks only in unthinned plots (approximately 37 m2/ha basal area). We discuss our results in terms of management implications for bark beetle trapping and control.
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...
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
Attraction of the southern pine beetle, Dendroctonus frontalis, to pheromone components of the western pine beetle, Dendroctonus brevicomis (Coleoptera: Curculionidae: Scolytinae), in an allopatric zone
Deepa S. Pureswaran; Richard W. Hofstetter; Brian T. Sullivan
Subtle differences in pheromone components of sympatric species should be attractive only to the producing species and unattractive or repellent to the nonproducing species, and thereby maintain reproductive isolation and reduce competition between species. Bark beetles Dendroctonus brevicomis and D. frontalis (Coleoptera: Curculionidae) are known to...
Byers, John A.; Zhang, Qing-He; Birgersson, Göran
The bark beetle, Pityogenes bidentatus (Coleoptera: Scolytidae), searches in mixed conifer and deciduous forests of northern Europe for suitable branches of its host, Scots pine (Pinus sylvestris). We tested whether odors from several diverse nonhost trees and plants common in the habitat (e.g., mountain ash, Sorbus aucuparia; oak, Quercus robur; alder buckthorn, Frangula alnus; blueberry, Vaccinium myrtillus; raspberry, Rubus idaeus; and grass, Deschampsia flexuosa) would reduce the attraction of the bark beetle to traps releasing its aggregation pheromone components in the field. Volatiles from the leaves or bark of each of these plants significantly reduced the attraction of the beetles to their pheromone. Odors collected from these nonhosts and analyzed by GC/MS contained monoterpenes, sesquiterpenes, and ``green-leaf'' alcohols, several of which (e.g., 1-octene-3-ol and β-caryophyllene) reduced the attraction to pheromone in the field and elicited electroantennographic responses. In the laboratory, reproduction by the beetle was marginal in nonhost Norway spruce, Picea abies, and was absent in the other nonhost trees. Olfactory avoidance of unsuitable nonhosts may have evolved due to advantages in avoiding mistakes during host selection.
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
Kevin J. Dodds
Full Text Available We investigated two methods to create white pine and red maple snags in a forested setting. The first involved injecting trees with ethanol at two times (single Ethanol (ETOH and double ETOH injections to increase attractiveness to insects and elicit attacks on trees. The second method was unique to white pines and involved both injection treatments in combination with baiting trees with Ips-specific pheromones. Three of five white pines from the double ETOH treatment died in the second year. Species including Ips pini (Say, Ips grandicollis Eichhoff, Orthotomicus caelatus Eichhoff, Crypturgus borealis Swaine and Monochamus notatus (Drury responded more strongly to at least one of the treatments over control trees. However, there were no differences found in individual Scolytinae or Cerambycidae species response to treatments in red maple. Fitness (FV/FM and vitality (PIabs were both significantly reduced in both ETOH treatments compared to controls in white pine. In red maple, fitness was reduced in the double ETOH treated trees but the final mean FV/FM values were within the approximate optimal of health. Ethanol injections, in combination with Ips-specific semiochemicals, show promise for creating standing coarse woody debris (CWD in white pine. Injecting ethanol was not effective for stressing red maple.
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, ...
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...
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 J. A.
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.
In an earlier field experiment, natural enemies of the bark beetle, Ips typographus (L) were estimated to have reduced bark beetle productivity by more than 80 percent. To test this hypothesis, spruce logs (Picea abies) were placed in the forest in the spring, prior to commencement of flight by I. typographus....
Rochat, Didier; Morin, Jean-Paul; Kakul, Titus; Beaudoin-Ollivier, Laurence; Prior, Robert; Renou, Michel; Malosse, Isabelle; Stathers, Tanya; Embupa, Sebastian; Laup, Samson
Laboratory and field investigations were carried out to investigate the nature and role of the male pheromone emitted by the Dynast beetle Scapanes australis and to develop a mass trapping technique against this major coconut pest in Papua New Guinea. We report the biological data obtained from natural and synthetic pheromone, previously described as an 84:12:4 (w/w) mixture of 2-butanol (1), 3-hydoxy-2-butanone (2), and 2,3-butanediol (3). EAG recordings from natural and synthetic pheromone and a pitfall olfactometer were poorly informative. In contrast, extensive field trapping trials with various synthetic pheromone mixtures and doses showed that 1 and 2 (formulated in polyethylene sachets in 90:5 v/v ratio) were necessary and sufficient for optimum long-range attraction. Beetles were captured in traps baited with racemic 1 plus 2, with or without a stereoisomer mixture of 3 (2.5- to 2500-mg/day doses). Plant pieces, either sugarcane or coconut, enhanced captures by the synthetic pheromone, which was active alone. Traps with the pheromone caught both sexes in a 3:2 female-male ratio. A pheromone-based mass trapping led to the capture of 2173 beetles in 14 traps surrounding 40 ha of a cocoa-coconut plantation. The captures followed a log-linear decrease during the 125-week trapping program. The role of the male pheromone and its potential for crop protection are discussed.
Paul Meznarich; Robert Progar
In the last decade, pine forests throughout much of the western United States have been ravaged by the mountain pine beetle (Dendroctonus ponderosae). This bark beetle is native to the United States and has been responsible for massive tree kills in the past. The current outbreak, however, has been notably severe and wide ranging and the effects have been more dramatic...
Richard H. Smith
Residual effectiveness of nine insecticides applied to bark was tested against western, mountain, and Jeffrey pine beetles. Ponderosa and Jeffrey pine trees were treated and logs cut from them 2 to 13 months later, and bioassayed with the three beetles. The insecticides were sprayed at the rate of 1 gal (3.8 l) per 40- or 80-ftÂ² (3.6 or 7.2 mÂ²) bark surface at varying...
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.
Mitchell, Robert F; Reagel, Peter F; Wong, Joseph C H; Meier, Linnea R; Silva, Weliton Dias; Mongold-Diers, Judith; Millar, Jocelyn G; Hanks, Lawrence M
Recent research has shown that volatile sex and aggregation-sex pheromones of many species of cerambycid beetles are highly conserved, with sympatric and synchronic species that are closely related (i.e., congeners), and even more distantly related (different subfamilies), using the same or similar pheromones. Here, we investigated mechanisms by which cross attraction is averted among seven cerambycid species that are native to eastern North America and active as adults in spring: Anelaphus pumilus (Newman), Cyrtophorus verrucosus (Olivier), Euderces pini (Olivier), Neoclytus caprea (Say), and the congeners Phymatodes aereus (Newman), P. amoenus (Say), and P. varius (F.). Males of these species produce (R)-3-hydroxyhexan-2-one as their dominant or sole pheromone component. Our field bioassays support the hypothesis that cross attraction between species is averted or at least minimized by differences among species in seasonal phenology and circadian flight periods of adults, and/or by minor pheromone components that act as synergists for conspecifics and antagonists for heterospecifics.
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...
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...
Archana Vasanthakumar; Yasmin Cardoza; Italo Delalibera; Patrick Schloss; Jo Handelsman; Kier Klepzig; Kenneth Raffa
Bark beetles are known to have complex associations with a variety of microorganisms (Paine and others 1987; Ayres and others 2000; Six and Klepzig 2004). However, most of our knowledge involves fungi, particularly external species. In contrast, we know very little about their associations with bacterial gut symbionts (Bridges 1981). Similarly, work with wood...
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...
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...
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.
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...
Peng, C; Weiss, M J
Laboratory olfactometer bioassays and field trapping experiments showed that the flea beetle,Phyllotreta cruciferae (Goeze), was highly attracted by oilseed rape(Brassica napus L.) when flea beetles were on the plant. This attraction was mediated by a flea beetle-produced aggregation pheromone based upon: (1) Oilseed rape damaged mechanically, or byP. cruciferae, or by diamondback moth,Plutella xylostella (L.), did not attractP. cruciferae. (2) Contact with the plants or feeding was required for the production of aggregation pheromone because oilseed rape alone was not attractive when separated from flea beetles by a screen. (3) Equal numbers of males and females were attracted.
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. PMID:24073204
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.
E. Dunn; J. Hough-Goldstein; L. M. Hanks; J. G. Millar; V. D' Amico
Cerambycid beetles (Coleoptera: Cerambycidae) can locate suitable hosts and mates by sensing pheromones and plant volatiles. Many cerambycid pheromone components have been identified and are now produced synthetically for trap lures. The range over which these lures attract cerambycids within a forest, and the tendency for cerambycids to move out of a forest in...
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...
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...
Goran Birgersson; Gary L. DeBarr; Peter de Groot; Mark J. Dalusky; Harold D. Pierce; John H. Borden; Holger Meyer; Wittko Francke; Karl E. Espelie; C. Wayne Berisford
Female white pine cone beetles, Conophrhorus coniperda, attacking second-year cones of eastern white pine, Pinus strobus L., produced a sex-specific pheromone that attracted conspecific males in laboratory bioassays and to field traps. Beetle response was enhanced by host monoterpenes. The female-produced compound was identified in...
The major bark beetle threat to Norway spruce (Picea abies (L.) Karst.) in Eurasia is the spruce bark beetle Ips typographus. Beetles cause damage after population build-up in defenseless trees. To minimize attacks, timely removal of these trees is important. This is practiced by clearing of wind throws and sanitation felling. Thus, knowledge about the region-specific flight pattern and voltinism of I. typographus is necessary for efficient pest management. This thesis focuses on the ...
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...
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.
Brian T. Sullivan; Cavell Brownie; JoAnne P. Barrett
The southern pine beetle Dendroctonus frontalis Zimmermann (Coleoptera: Curculionidae: Scolytinae) is attracted to an aggregation pheromone that includes the multifunctional pheromone component endobrevicomin. The effect of endo-brevicomin on attractive lures varies from strong enhancement to reduction of beetle attraction depending upon release rate, lure component...
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.
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...
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...
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...
Wu, Zhongtao; Buter, Jeffrey; Minnaard, Adriaan J.; Jäger, Manuel; Dickschat, J.S.
A novel synthesis of the aggregation pheromone of the Colorado potato beetle, Leptinotarsa decemlineata, has been developed based on a Sharpless asymmetric epoxidation in combination with a chemoselective alcohol oxidation using catalytic [(neocuproine)PdOAc](2)OTf2. Employing this approach, the
Daniel R. Miller; B. Staffan Lindgren; John H. Borden
We conducted seven behavioral choice tests with Lindgren multiple-funnel traps in stands of mature lodgepole pine in British Columbia, from 1988 to 1994, to determine the dosedependent responses of the mountain pine beetle, Dendroctonus ponderosae Hopkins, to its pheromones. Amultifunctional dose-dependent response was exhibited by D. ...
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
Indriyanti, D. R.; Lutfiana, J. E.; Widiyaningrum, P.; Susilowati, E.; Slamet, M.
Oryctes rhinoceros (Coleoptera: Scarabaeidae) is the most serious pest of coconut plantations in Indonesia. Jerukwangi Village is O. rhinoceros attacked one of the coconuts producing villages with more than 75% of the coconut plant population O. rhinoceros. The study aimed to monitor the population and analyze the sex ratio of O. rhinoceros that were attracted to aggregation pheromones in the field. Aggregation pheromones is a chemical compound containing Ethyl 4-methyl octanoate. The pheromone compounds were placed in traps (buckets), hung 2 meters above the ground. The traps were observed, and the beetles trapped were counted every week. In 12 weeks of monitoring, the traps captured 101 insects consist of 90.1% O. rhinoceros and 9.9% other insect species (Rhynchophorus ferrugineus and Xylotrupes gideon). This result indicates the high population of O. rhinoceros in the field. Aggregation pheromone is useful for attracting females. Rhinoceros by 61% and the males by 39%. The advantage of research is it can be used in integrated pest management (IPM) packages for monitoring of beetle population, and removal of beetles.
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...
Full Text Available Orientation of insects to host plants and conspecifics is the result of detection and integration of chemical and physical cues present in the environment. Sensory organs have evolved to be sensitive to important signals, providing neural input for higher order multimodal processing and behavioral output. Here we report experiments to determine decisions made by Colorado potato beetle (CPB, Leptinotarsa decemlineata, in response to isolated stimuli and multimodal combinations of signals on a locomotion compensator. Our results show that in complete darkness and in the absence of other stimuli, pheromonal stimulation increases attraction behavior of CPB as measured in oriented displacement and walking speed. However, orientation to the pheromone is abolished when presented with the alternative stimulation of a low intensity yellow light in a dark environment. The ability of the pheromone to stimulate these diurnal beetles in the dark in the absence of other stimuli is an unexpected but interesting observation. The predominance of the phototactic response over that to pheromone when low intensity lights were offered as choices seems to confirm the diurnal nature of the insect. The biological significance of the response to pheromone in the dark is unclear. The phototactic response will play a key role in elucidating multimodal stimulation in the host-finding process of CPB, and perhaps other insects. Such information might be exploited in the design of applications to attract and trap CPB for survey or control purposes and other insect pests using similar orientation mechanisms.
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...
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...
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...
Brian H. Aukema; Richard A. Werner; Kirsten E. Haberkern; Barbara L. Illman; Murray K. Clayton; Kenneth F. Raffa
The spruce beetle, Dendroctonus rufipennis (Kirby), causes landscape level mortality to mature spruce (Picea spp.) throughout western and northern North America. As with other bark beetles, this beetle is associated with a variety of fungi, whose ecological functions are largely unknown. It has been proposed that the relative...
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
Weliton D Silva
Full Text Available We report the identification, synthesis, and field bioassay of a novel attractant pheromone produced by males of Eburodacrys vittata (Blanchard, a South American cerambycid beetle in the subfamily Cerambycinae. Headspace volatiles from males contained a sex-specific compound, identified as 10-methyldodecanal. In a field bioassay conducted in Brazil, significant numbers of males and females were caught in traps baited with synthesized racemic 10-methyldodecanal, consistent with the aggregation-sex pheromones produced by males of many cerambycine species. This compound represents a new structural class of cerambycid pheromones, and it is the first pheromone identified for a species in the tribe Eburiini.
Hallett, R H; Perez, A L; Gries, G; Gries, R; Pierce, H D; Yue, J; Oehlschlager, A C; Gonzalez, L M; Borden, J H
Male coconut rhinoceros beetles,Oryctes rhinoceros (L.), produce three sex-specific compounds, ethyl 4-methyloctanoate, ethyl 4-methylheptanoate, and 4-methyloctanoic acid, the first of which is an aggregation pheromone. Synthesis of these compounds involving conjugate addition of organocuprates to ethyl acrylate is reported. In field trapping experiments, (4S)-ethyl 4-methyloctanoate and the racemic mixture were equally attractive and 10 times more effective in attracting beetles than ethyl chrysanthemumate, a previously recommended attractant. Ethyl 4-methylheptanoate was as attractive as ethyl chrysanthemumate and more attractive than 4-methyloctanoic acid, but further studies are required before it can be classed as an aggregation pheromone. Compared to ethyl 4-methyloctanoate alone, combinations of the three male-produced compounds did not increase attraction, whereas addition of freshly rotting oil palm fruit bunches to pheromone-baited traps significantly enhanced attraction. With increasing dose, captures ofO. rhinoceros increased, but doses of 6, 9, and 18 mg/day were competitive with 30 mg/day lures. Newly designed vane traps were more effective in capturing beetles than were barrier or pitfall traps. Results of this study indicate that there is potential for using ethyl 4-methyloctanoate in operational programs to controlO. rhinoceros in oil palm plantations.
Claudia Cano-Ramirez; Maria Fernanda Lopez; Ana K. Cesar-Ayala; Veronica Pineda-Martinez; Brian T. Sullivan; Gerardo and Zuniga
Bark beetles oxidize the defensive monoterpenes of their host trees both to detoxify them and convert them into components of their pheromone system. This oxidation is catalyzed by cytochrome P450 enzymes and occurs in different tissues of the insect, including the gut (i.e., the site where the beetle's pheromones are produced and accumulated) and the antennae (i....
Aukema, Brian H.; Zhu, Jun; Møller, Jesper
, however, due to the requirement of long-term monitoring and high degrees of spatial and temporal covariance. We censused more than 2700 trees annually over 7 years, and at the end of 17 years, in a mature red pine plantation. Trees were measured for the presence of bark beetles and wood borers that breed...... within the primary stem, root weevils that breed in root collars, and bark beetles that breed in basal stems. We quantify the sequence of events that drive this decline syndrome, with the primary emergent pattern being an interaction between below- and above-ground herbivores and their fungal symbionts......, and elevated temperature slightly accentuates this effect. New gaps can arise from such trees as they subsequently become epicenters for the full complex of organisms associated with this decline, but this is not common. As Ips populations rise, there is some element of positive feedback...
Serrano, Jacqueline M; Collignon, R Maxwell; Zou, Yunfan; Millar, Jocelyn G
To date, all known or suspected pheromones of click beetles (Coleoptera: Elateridae) have been identified solely from species native to Europe and Asia; reports of identifications from North American species dating from the 1970s have since proven to be incorrect. While conducting bioassays of pheromones of a longhorned beetle (Coleoptera: Cerambycidae), we serendipitously discovered that males of Cardiophorus tenebrosus L. and Cardiophorus edwardsi Horn were specifically attracted to the cerambycid pheromone fuscumol acetate, (E)-6,10-dimethylundeca-5,9-dien-2-yl acetate, suggesting that this compound might also be a sex pheromone for the two Cardiophorus species. Further field bioassays and electrophysiological assays with the enantiomers of fuscumol acetate determined that males were specifically attracted by the (R)-enantiomer. However, subsequent analyses of extracts of volatiles from female C. tenebrosus and C. edwardsi showed that the females actually produced a different compound, which was identified as (3R,6E)-3,7,11-trimethyl-6,10-dodecadienoic acid methyl ester (methyl (3R,6E)-2,3-dihydrofarnesoate). In field trials, both the racemate and the (R)-enantiomer of the pheromone attracted similar numbers of male beetles, suggesting that the (S)-enantiomer was not interfering with responses to the insect-produced (R)-enantiomer. This report constitutes the first conclusive identification of sex pheromones for any North American click beetle species. Possible reasons for the strong and specific attraction of males to fuscumol acetate, which is markedly different in structure to the actual pheromone, are discussed.
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...
Brice A. McPherson; Nadir Erbilgin; David L. Wood; Pavel Svihra; Andrew J. Storer; Richard B. Standiford
Sudden oak death, caused by Phytophthora ramorum (Werres, de Cock & Man in?t Veld), has killed thousands of oaks (Quercus spp.) in coastal California forests since the mid-1990s. Bark and ambrosia beetles that normally colonize dead or severely weakened trees selectively tunnel into the bleeding cankers that are the first...
D. L. Six; B. J. Bentz
In this study, we report evidence that temperature plays a key role in determining the relative abundance of two mutualistic fungi associated with an economically and ecologically important bark beetle, Dendroctonus ponderosae. The symbiotic fungi possess different optimal temperature ranges. These differences determine which fungus is vectored by...
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
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....
T. Evan Nebeker
Management of members of the southern pine bark beetle guild, which consists of five species, is a continually evolving process. A number of management strategies and tactics have remained fairly constant over time as new ones are being added. These basic practices include doing nothing, direct control, and indirect control. This chapter focuses primarily on the latter...
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
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...
John Moser; Heino Konrad; Stacy Blomquist; Thomas Kirisits
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...
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...
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.
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
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
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....
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...
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...
Chakravarthy, A K; Chandrashekharaiah, M; Kandakoor, Subhash B; Nagaraj, D N
Red palm weevil and Rhinoceros beetle are the major pests inflicting severe damage to coconut palms. Due to ineffectiveness of the current management practices to control the two important pests on coconut, a study was conducted to know the attractiveness of red palm weevil and rhinoceros beetle to aggregation pheromone. Olfactometer studies indicated that the aggregation pheromone of red palm weevil and rhinoceros beetle attracted significantly more number of weevils (13.4 females and 7.6 male weevils) and beetles (6.5 male and 12.3 female beetles), respectively than control. Similarly, field studies found that both 750 and 1000 mg pheromone dosage lures of red palm weevil and rhinoceros beetle trapped significantly higher numbers of weevils (695.80 and 789 weevils, respectively) and beetles (98 and 108 beetles, respectively) in traps (P rhinoceros beetle population got trapped. Observations indicated activity of red palm weevil throughout the year and of rhinoceros beetle from September to March around Bangalore, South India. Pheromone traps for red palm weevil can be placed in fields from June to August and October to December and September to February for rhinoceros beetle. Population reductions of the two coleopteran pests by pheromone traps are compatible with mechanical and cultural management tools with cumulative effects.
William Shepherd; Brian Sullivan; Bradley Hoosier; JoAnne Barrett; Tessa Bauman
We conducted laboratory and field bioassays to characterize the pheromone system of an ash bark beetle, Hylesinus pruinosus Eichhoff (Coleoptera: Curculionidae: Scolytinae). Solitary females in newly initiated galleries in ash logs produced (+)-exo-brevicomin, whereas male beetles paired with females produced (+)-endo-brevicomin, lesser quantities of...
Millar, Jocelyn G; Mitchell, Robert F; Mongold-Diers, Judith A; Zou, Yunfan; Bográn, Carlos E; Fierke, Melissa K; Ginzel, Matthew D; Johnson, Crawford W; Meeker, James R; Poland, Therese M; Ragenovich, Iral; Hanks, Lawrence M
The pheromone components of many cerambycid beetles appear to be broadly shared among related species, including species native to different regions of the world. This apparent conservation of pheromone structures within the family suggests that field trials of common pheromone components could be used as a means of attracting multiple species, which then could be targeted for full identification of their pheromones. Here, we describe the results of such field trials that were conducted in nine states in the northeastern, midwestern, southern, and western United States. Traps captured 12,742 cerambycid beetles of 153 species and subspecies. Species attracted in significant numbers to a particular treatment (some in multiple regions) included 19 species in the subfamily Cerambycinae, 15 species in the Lamiinae, one species in the Prioninae, and two species in the Spondylidinae. Pheromones or likely pheromones for many of these species, such as 3-hydroxyhexan-2-one and syn- and anti-2,3-hexanediols for cerambycine species, and fuscumol and/or fuscumol acetate for lamiine species, had already been identified. New information about attractants (in most cases likely pheromone components) was found for five cerambycine species (Ancylocera bicolor [Olivier], Elaphidion mucronatum [Say], Knulliana cincta cincta [Drury], Phymatodes aeneus LeConte, and Rusticoclytus annosus emotus [Brown]), and five lamiine species (Ecyrus dasycerus dasycerus [Say], Lepturges symmetricus [Haldeman], Sternidius misellus [LeConte], Styloleptus biustus biustus [LeConte], and Urgleptes signatus [LeConte]). Consistent attraction of some species to the same compounds in independent bioassays demonstrated the utility and reliability of pheromone-based methods for sampling cerambycid populations across broad spatial scales. © 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.
Darrell W. Ross; Gary E. Daterman; A. Steven Munson
The spruce beetle, Dendroctonus rufipennis (Kirby), produces the antiaggregation pheromone 3-methylcyclohex-2-en- 1-one (MCH) (Rudinsky et al. 1974). MCH has reduced the numbers of spruce beetles attracted to infested logs and synthetic semiochemical lures or reduced colonization rates throughout the beetles range (Kline
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
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...
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...
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...
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...
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...
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, J C H; Zou, Y; Millar, J G; Hanks, L M
Here, we describe a field experiment that tested for attraction of cerambycid beetles to odors from angiosperm hosts, and whether plant volatiles also serve to enhance attraction of beetles to their aggregation-sex pheromones. Traps were baited with a blend of synthesized chemicals that are common pheromone components of species in the subfamilies Cerambycinae and Lamiinae. The source of plant volatiles was chipped wood from trees of three angiosperm species, as well as from one nonhost, gymnosperm species. Bioassays were conducted in wooded areas of east-central Illinois. Traps were baited with the pheromone blend alone, the blend + wood chips from one tree species, wood chips alone, or a solvent control lure. Seven species of cerambycids were significantly attracted to the pheromone blend, with or without wood chips. In two cases, wood chips from angiosperms appeared to enhance attraction to pheromones, whereas they inhibited attraction in another three cases. Pine chips did not strongly influence attraction of any species. Overall, our results suggest that host plant volatiles from wood chips may improve trap catch with synthesized pheromones for some cerambycid species, but the effect is not general, necessitating case-by-case testing to determine how individual target species are affected. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: email@example.com.
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.
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)
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...
C.J. Fettig; A.S. Munson; S.R. McKelvey; DeGomez T.E.
Bark beetles are commonly recognized as important tree mortality agents in western coniferous forests, but relatively few species (<25) are capable of killing apparently-healthy trees. However, during the last decade extensive levels of tree mortality were attributed to bark beetle outbreaks in...
Kärvemo, Simon; Schroeder, Leif Martin
The European spruce bark beetle (Ips typographus) and the North American mountain pine beetle (Dendroctonus ponderosae) may kill millions of trees during outbreak periods. Both species have also experienced large outbreaks in recent years. But the magnitude of the outbreaks of D. ponderosae is much larger. In this review we compare the outbreak history of I. typographus in Sweden with D. ponderosae in British Columbia in Canada. We also discuss some possible explanations for the difference in...
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...
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.
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.
Mikkelson, K.; Dickenson, E.; Maxwell, R. M.; McCray, J. E.; Sharp, J. O.
In the previous decade, millions of acres in the Rocky Mountains of Colorado have been infested by the mountain pine beetle (MPB) leading to large-scale tree mortality. These vegetation changes can impact hydrological and biogeochemical processes, possibly altering the leaching of natural organic matter to surrounding waters and increasing the potential for harmful disinfection byproducts (DBP) during water treatments. To investigate these adverse outcomes, we have collected water quality data sets from local water treatment facilities in the Rocky Mountains of Colorado that have either been infested with MPB or remain a control. Results demonstrate significantly more total organic carbon (TOC) and DBPs in water treatment facilities receiving their source water from infested watersheds as compared to the control sites. Temporal DBP concentrations in MPB-watersheds also have increased significantly in conjunction with the bark-beetle infestation. Interestingly, only modest increases in TOC concentrations were observed in infested watersheds despite more pronounced increases in DBP concentrations. Total trihalomethanes, a heavily regulated DBP, was found to approach the regulatory limit in two out of four reporting quarters at facilities receiving their water from infested forests. These findings indicate that bark-beetle infestation alters TOC composition and loading in impacted watersheds and that this large-scale phenomenon has implications on the municipal water supply in the region.
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
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
Ragoussis, Valentine; Giannikopoulos, Alexandros; Skoka, Efthymia; Grivas, Panagiotis
(+/-)-4-Methyloctanoic acid and its ethyl ester are aggregation pheromones of many rhinoceros beetles of the genus Oryctes and are investigated for the control of these pests by olfactory trapping. A simple, economical, and high-yield (>50%) synthesis of (+/-)-4-methyloctanoic acid and its ethyl ester is presented starting from n-hexanal. The key step in this sequence is an orthoester Claisen rearrangement for the elongation of the carbon chain by two.
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
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...
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...
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-...
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...
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
Francisco Armendariz-Toledano; Alicia Nino; Brian T. Sullivan; Lawrence R. Kirkendall; Gerado Zunig
The bark beetle Dendroctonus mesoamericanus sp. nov. is described from a population in Parque Nacional Lagunas de Montebello, La Trinitaria, Chiapas, Mexico. This species belongs to the D. frontalis complex, which includes D. adjunctus Blandford 1897, D. approximatus Dietz 1890, D....
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...
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.
Susoy, V; Herrmann, M
Host-symbiont systems are of particular interest to evolutionary biology because they allow testable inferences of diversification processes while also providing both a historical basis and an ecological context for studies of adaptation. Our investigations of bark beetle symbionts, predatory nematodes of the genus Micoletzkya, have revealed remarkable diversity of the group along with a high level of host specificity. Cophylogenetic analyses suggest that evolution of the nematodes was largely influenced by the evolutionary history of beetles. The diversification of the symbionts, however, could not be attributed to parallel divergence alone; our results indicate that adaptive radiation of the nematodes was shaped by preferential host shifts among closely related beetles along with codivergence. Whereas ecological and geographic isolation have played a major role in the diversification of Micoletzkya at shallow phylogenetic depths, adaptations towards related hosts have played a role in shaping cophylogenetic structure at a larger evolutionary scale. © 2014 The Authors. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.
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.
Youngblood, A.; Grace, J.B.; Mciver, J.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 in
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.
Erbilgin, Nadir; Cale, Jonathan A; Hussain, Altaf; Ishangulyyeva, Guncha; Klutsch, Jennifer G; Najar, Ahmed; Zhao, Shiyang
Recent mountain pine beetle outbreaks in western North America killed millions of lodgepole pine trees, leaving few survivors. However, the mechanism underlying the ability of trees to survive bark beetle outbreaks is unknown, but likely involve phytochemicals such as monoterpenes and fatty acids that can drive beetle aggregation and colonization on their hosts. Thus, we conducted a field survey of beetle-resistant lodgepole pine (Pinus contorta) trees to retrospectively deduce whether these phytochemicals underlie their survival by comparing their chemistry to that of non-attacked trees in the same stands. We also compared beetle attack characteristics between resistant and beetle-killed trees. Beetle-killed trees had more beetle attacks and longer ovipositional galleries than resistant trees, which also lacked the larval establishment found in beetle-killed trees. Resistant trees contained high amounts of toxic and attraction-inhibitive compounds and low amounts of pheromone-precursor and synergist compounds. During beetle host aggregation and colonization, these compounds likely served three critical roles in tree survival. First, low amounts of pheromone-precursor (α-pinene) and synergist (mycrene, terpinolene) compounds reduced or prevented beetles from attracting conspecifics to residual trees. Second, high amounts of 4-allyanisole further inhibited beetle attraction to its pheromone. Finally, high amounts of toxic limonene, 3-carene, 4-allyanisole, α-linolenic acid, and linoleic acid inhibited beetle gallery establishment and oviposition. We conclude that the variation of chemotypic expression of local plant populations can have profound ecological consequences including survival during insect outbreaks.
Huber, D P W; Erickson, M L; Leutenegger, C M; Bohlmann, J; Seybold, S J
We have identified cDNAs and characterized the expression of 13 novel cytochrome P450 genes of potential importance in host colonization and reproduction by the California fivespined ips, Ips paraconfusus. Twelve are of the Cyp4 family and one is of the Cyp9 family. Following feeding on host Pinus ponderosa phloem, bark beetle transcript levels of several of the Cyp4 genes increased or decreased in males only or in both sexes. In one instance (IparaCyp4A5) transcript accumulated significantly in females, but declined significantly in males. The Cyp9 gene (Cyp9T1) transcript levels in males were > 85 000 x higher at 8 h and > 25 000 x higher at 24 h after feeding compared with nonfed controls. Transcript levels in females were approximately 150 x higher at 24 h compared with nonfed controls. Cyp4G27 transcript was present constitutively regardless of sex or feeding and served as a better housekeeping gene than beta-actin or 18S rRNA for the real-time TaqMan polymerase chain reaction analysis. The expression patterns of Cyp4AY1, Cyp4BG1, and, especially, Cyp9T1 in males suggest roles for these genes in male-specific aggregation pheromone production. The differential transcript accumulation patterns of these bark beetle P450s provide insight into ecological interactions of I. paraconfusus with its host pines.
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.
Chemnitz, Johanna; Bagrii, Nadiia; Ayasse, Manfred; Steiger, Sandra
Life history theory predicts a trade-off between male sexual trait expression and immunocompetence. Using burying beetles, Nicrophorus vespilloides, as a model, we investigated the relationship between male immune function, sex pheromone emission, and attractiveness under field conditions. In the first experiment, we tested whether there is a positive correlation between immune capacity, sex pheromone characteristics (quantity, relative composition, and time invested in pheromone emission), and male attractiveness. As a measurement of immune capacity, we used an individual's encapsulation ability against a novel antigen. In the second experiment, we specifically examined whether a trade-off between chemical trait expression and immune function existed. To this end, we challenged the immune system and measured the subsequent investment in sex pheromone emission and the attractiveness of the male under field conditions. We found that a male's immunocompetence was neither related to the emission of the male's sex pheromone nor to its attractiveness in the field. Furthermore, none of the immune-challenge treatments affected the subsequent investment in pheromone emission or number of females attracted. However, we showed that the same males that emitted a high quantity of their sex pheromone in the laboratory were able to attract more females in the field. Our data suggest that the chemical signal is not a reliable predictor of a male's immunocompetence but rather is a general important fitness-related trait, with a higher emission of the sex pheromone measured in the laboratory directly affecting the attractiveness of a male under field conditions.
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.
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.
Rochat, D; Ramirez-Lucas, P; Malosse, C; Aldana, R; Kakul, T; Morin, J P
Solid-phase microextraction (SPME) samplings from live insects or natural secretion allowed one to identify the aggregation pheromones of the pest beetles Scapanes australis and Strategus aloeus by efficient and rapid isolation of their highly volatile (72 < M(r) < 116) components. S. australis male pheromone was identified as a 84:12:4 (w/w) mixture of 2-butanol [67:33 (R)-(-):(S)-(+) ratio], 3-hydroxy-2-butanone and 2,3-butanediol [43:17:40 (R,R)-(-):(S,S)-(+):meso ratio], and S. aloeus pheromone as a 95.5:4.0:0.5 (w/w) mixture of 2-butanone, 3-pentanone and sec.-butyl acetate by GC-MS using conventional and chiral capillary columns. This is the first report of Scarabaeidae pheromones based on such small and common molecules.
Full Text Available The spruce bark beetle, Ips typographus (L. (Coleoptera: Curculionidae, Scolytinae, is one of the most destructive insects infesting spruce forests in Europe. Data concerning infestations of I. typographus occurring over the last 19 years (1994–2012 on the Southern Alps were analyzed in seven spruce forest types: (1 pure spruce plantations; (2 pure spruce reforestations; (3 pure spruce mountain forests; (4 pure spruce alpine forests; (5 spruce-conifer mixed forests; (6 spruce-broadleaf mixed forests; and (7 spruce-conifer-broadleaf mixed forests. The collected data included the amount of I. typographus damage and the location and composition of the infested forests. The results indicate that different forest types are differently susceptible to I. typographus. Plantations, reforestations and mountain spruce forests show mean damage and mean number of infestations higher than other forest types. Within pure spruce forests, alpine forests growing at high elevations (>1300 m suffer low damage. Furthermore, the mean number of infestation spots recorded annually in the different spruce forest types is negatively correlated with a Naturality Index value. The results suggest that forest composition and elevation are the main factors driving the risk of I. typographus damage. A new management strategy for some spruce forest types is needed, with a progressive reduction of pure spruce forests at low altitude and an increase of broadleaf composition.
Salle, Aurelien; Ye, Hui; Yart, Annie; Lieutier, François
We examined the influence of seasonal water stress on the resistance of Pinus yunnanensis (Franch.) to inoculation with Leptographium yunnanense, a pathogenic fungus associated with the aggressive bark beetle, Tomicus n. sp. Experiments took place between October 1997 and November 1999 in two plots located at the top and at the foot of a hill in Shaogiu, China, a region characterized by dry winters and wet summers. Following isolated and mass fungal inoculations, we observed the reaction zone length, fungal growth in the phloem, and the occlusion, blue-staining and specific hydraulic conductivity of the sapwood. Measurements of soil and needle water contents and predawn needle water potentials confirmed that trees were subject to mild water stress during winter, especially at the drier hilltop site. Measures of tree resistance to fungal infection of phloem and sapwood were congruent and indicated that trees were most susceptible to inoculation during the wet summer, especially at the lower-elevation plot. Specific hydraulic conductivity decreased after inoculation in summer. The results indicate that mild seasonal water stress is not likely responsible for the recent extensive damage to young P. yunnanensis stands by Tomicus n. sp. in the vicinity of our study plots. Rather, the results suggest that mild water stress enhances tree resistance to fungal pathogens associated with Tomicus n. sp.
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.
Musa, Najihah; Andersson, Klas; Burman, Joseph; Andersson, Fredrik; Hedenström, Erik; Jansson, Nicklas; Paltto, Heidi; Westerberg, Lars; Winde, Inis; Larsson, Mattias C; Bergman, Karl-Olof; Milberg, Per
The European red click beetle, Elater ferrugineus L., is associated with wood mould in old hollow deciduous trees. As a result of severe habitat fragmentation caused by human disturbance, it is threatened throughout its distribution range. A new pheromone-based survey method, which is very efficient in detecting the species, was used in the present study to relate the occurrence of E. ferrugineus to the density of deciduous trees. The latter data were from a recently completed regional survey in SE Sweden recording >120,000 deciduous trees. The occurrence of E. ferrugineus increased with increasing amount of large hollow and large non-hollow trees in the surrounding landscape. Quercus robur (oak) was found to be the most important substrate for E. ferrugineus, whereas two groups of tree species (Carpinus betulus, Fagus sylvatica, Ulmus glabra, vs. Acer platanoides, Aesculus hippocastanum, Fraxinus excelsior, Tilia cordata) were less important but may be a complement to oak in sustaining populations of the beetle. The occurrence of E. ferrugineus was explained by the density of oaks at two different spatial scales, within the circle radii 327 m and 4658 m. In conclusion, priority should be given to oaks in conservation management of E. ferrugineus, and then to the deciduous trees in the genera listed above. Conservation planning at large spatial and temporal scales appears to be essential for long-term persistence of E. ferrugineus. We also show that occurrence models based on strategic sampling might result in pessimistic predictions. This study demonstrates how pheromone-based monitoring make insects excellent tools for sustained feedback to models for landscape conservation management.
Full Text Available The European red click beetle, Elater ferrugineus L., is associated with wood mould in old hollow deciduous trees. As a result of severe habitat fragmentation caused by human disturbance, it is threatened throughout its distribution range. A new pheromone-based survey method, which is very efficient in detecting the species, was used in the present study to relate the occurrence of E. ferrugineus to the density of deciduous trees. The latter data were from a recently completed regional survey in SE Sweden recording >120,000 deciduous trees. The occurrence of E. ferrugineus increased with increasing amount of large hollow and large non-hollow trees in the surrounding landscape. Quercus robur (oak was found to be the most important substrate for E. ferrugineus, whereas two groups of tree species (Carpinus betulus, Fagus sylvatica, Ulmus glabra, vs. Acer platanoides, Aesculus hippocastanum, Fraxinus excelsior, Tilia cordata were less important but may be a complement to oak in sustaining populations of the beetle. The occurrence of E. ferrugineus was explained by the density of oaks at two different spatial scales, within the circle radii 327 m and 4658 m. In conclusion, priority should be given to oaks in conservation management of E. ferrugineus, and then to the deciduous trees in the genera listed above. Conservation planning at large spatial and temporal scales appears to be essential for long-term persistence of E. ferrugineus. We also show that occurrence models based on strategic sampling might result in pessimistic predictions. This study demonstrates how pheromone-based monitoring make insects excellent tools for sustained feedback to models for landscape conservation management.
Sandoval Rodríguez, Carla; Cognato, Anthony I; Righi, Ciro Abbud
Land use changes and forest fragmentation result in biodiversity loss and displacement, with insects among the most affected groups. Among these, bark beetles (Curculionidae: Scolytinae) occupy a prominent position due to their close ties to food resources, i.e., trees, and importance as primary decomposers in forest ecosystems. Therefore, our study aimed to document scolytine biodiversity associated with landscape components that vary based on their physical or botanical composition. Bark beetle diversity was sampled monthly for 12 mo in an Atlantic forest remnant and five adjacent vegetation plots (mixed Agroforestry System-AFS, of native trees and fruit species; AFS of rubber trees and coffee plants; coffee monoculture; rubber monoculture; and pasture). In total, 1,833 individuals were sampled from 38 species of which 24 (63%) were detected in very low abundance. The remaining 14 species were more abundant and widespread almost in all areas. Hypothenemus hampei (Westwood), Premnobius cavipennis (Eichhoff), Hypothenemus sp1., and Xyleborus volvulus (Fabricius) were the most abundant. The greatest abundance and richness of bark beetles were found in the dry and cold season. The varied microclimatic conditions of the vegetation plots greatly affected the diversity of the Scolytinae. Solar radiation presented a significant negative effect on abundance in almost all the studied areas. The greatest scolytine diversity was found in anthropic areas with tree canopy structure. Open areas (pasture and coffee monocrop) had a lower species diversity. Similarly, a lower abundance and species richness were found for the Atlantic forest remnant. © The Authors 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 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.
Fettig, Christopher J; Munson, A Steven; McKelvey, Stephen R; Bush, Parshall B; Borys, Robert R
Bark beetles (Coleoptera: Curculionidae, Scolytinae) are recognized as the most important tree mortality agent in western coniferous forests. A common method of protecting trees from bark beetle attack is to saturate the tree bole with carbaryl (1-naphthyl methylcarbamate) using a hydraulic sprayer. In this study, we evaluate the amount of carbaryl drift (ground deposition) occurring at four distances from the tree bole (7.6, 15.2, 22.9, and 38.1 m) during conventional spray applications for protecting individual lodgepole pine (Pinus contorta Dougl. ex Loud.) from mountain pine beetle (Dendroctonus ponderosae Hopkins) attack and Engelmann spruce (Picea engelmannii Parry ex Engelm.) from spruce beetle (D. rufipennis [Kirby]) attack. Mean deposition (carbaryl + alpha-naphthol) did not differ significantly among treatments (nozzle orifices) at any distance from the tree bole. Values ranged from 0.04 +/- 0.02 mg carbaryl m(-2) at 38.1 m to 13.30 +/- 2.54 mg carbaryl m(-2) at 7.6 m. Overall, distance from the tree bole significantly affected the amount of deposition. Deposition was greatest 7.6 m from the tree bole and quickly declined as distance from the tree bole increased. Approximately 97% of total spray deposition occurred within 15.2 m of the tree bole. Application efficiency (i.e., percentage of insecticide applied that is retained on trees) ranged from 80.9 to 87.2%. Based on review of the literature, this amount of drift poses little threat to adjacent aquatic environments. No-spray buffers of 7.6 m should be sufficient to protect freshwater fish, amphibians, crustaceans, bivalves, and most aquatic insects. Buffers >22.9 m appear sufficient to protect the most sensitive aquatic insects (Plecoptera).
MacKay, Colin A; Sweeney, Jon D; Hillier, N Kirk
Longhorn wood-boring beetles (Coleoptera: Cerambycidae) use olfactory cues to find mates and hosts for oviposition. Tetropium fuscum (Fabr.) is an invasive longhorned wood-boring beetle originating from Europe that has been established in Nova Scotia, Canada, since at least 1990. This study used single sensillum recordings (SSR) to determine the response of olfactory receptor neurons (ORNs) in the antennal sensilla of male and female T. fuscum to different kinds of olfactory cues, namely host volatiles, non-host volatiles, the aggregation pheromone of T. fuscum (fuscumol), and an aggregation pheromone emitted by other species of longhorn beetles (3-hydroxyhexan-2-one). Each compound had been previously shown to elicit antennal activity in T. fuscum using electroantennography or had been shown to elicit behavioral activity in T. fuscum or other cerambycids. There have been very few SSR studies done on cerambycids, and ours is the first to compare response profiles of pheromone components as well as host and non-host volatiles. Based on SSR studies with other insects, we predicted we would find ORNs that responded to the pheromone alone (pheromone-specialists), as well as ORNs that responded only to host or non-host volatiles, i.e., separation of olfactory cue perception at the ORN level. Also, because male T. fuscum emerge earlier than females and are the pheromone-emitting sex, we predicted that the number of pheromone-sensitive ORNs would be greater in females than males. We found 140 ORNs housed within 97 sensilla that responded to at least one of the 13 compounds. Fuscumol-specific ORNs made up 15% (21/140) of all recordings, but contrary to our prediction, an additional 22 ORNs (16%) responded to fuscumol plus at least one other compound; in total, fuscumol elicited a response from 43/140 (31%) of ORNs with fuscumol-specific ORNs accounting for half of these. Thus, our prediction that pheromone reception would be segregated on specialist ORNs was only partially
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.
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.
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...
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
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
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...
Christopher J. Fettig; Kurt K. Allen; Robert R. Borys; John Christopherson; Christopher P. Dabney; Thomas J. Eager; Kenneth E. Gibson; Elizabeth G. Hebertson; Daniel F. Long; A. Steven Munson; Patrick J. Shea; Sheri L. Smith; Michael I. Haverty
High-value trees, such as those located in residential, recreational, or administrative sites, are particularly susceptible to bark beetle (Coleoptera: Curculionidae: Scolytinae) attack as a result of increased amounts of stress associated with drought, soil compaction, mechanical injury, or vandalism. Tree losses in these unique environments generally have a...
Christopher J. Fettig; Thomas E. DeGomez; Kenneth E. Gibson; Christopher J. Dabney; Robert R. Borys
Bark beetles (Coleoptera: Scolytidae) are commonly recognized as the most important mortality agent in western coniferous forests. High value trees, such as those located in residential, recreational, or administrative sites, are particularly susceptible to attack. Regardless of landowner objectives, tree losses in these unique environments generally have a...
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.
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...
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...
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
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.
Keefover-Ring, Ken; Trowbridge, Amy; Mason, Charles J; Raffa, Kenneth F
Ponderosa pine (Pinus ponderosa) is a major and widely distributed component of conifer biomes in western North America and provides substantial ecological and economic benefits. This tree is exposed to several tree-killing bark beetle-microbial complexes, including the mountain pine beetle (Dendroctonus ponderosae) and the phytopathogenic fungus Grosmannia clavigera that it vectors, which are among the most important. Induced responses play a crucial role in conifer defenses, yet these have not been reported in ponderosa pine. We compared concentrations of terpenes and a phenylpropanoid, two phytochemical classes with strong effects against bark beetles and their symbionts, in constitutive phloem tissue and in tissue following mechanical wounding or simulated D. ponderosae attack (mechanical wounding plus inoculation with G. clavigera). We also tested whether potential induced responses were localized or systemic. Ponderosa pines showed pronounced induced defenses to inoculation, increasing their total phloem concentrations of monoterpenes 22.3-fold, sesquiterpenes 56.7-fold, and diterpenes 34.8-fold within 17 days. In contrast, responses to mechanical wounding alone were only 5.2, 11.3, and 7.7-fold, respectively. Likewise, the phenylpropanoid estragole (4-allyanisole) rose to 19.1-fold constitutive levels after simulated attack but only 4.4-fold after mechanical wounding. Overall, we found no evidence of systemic induction after 17 days, which spans most of this herbivore's narrow peak attack period, as significant quantitative and compositional changes within and between terpenoid groups were localized to the wound site. Implications to the less frequent exploitation of ponderosa than lodgepole pine by D. ponderosae, and potential advantages of rapid localized over long-term systemic responses in this system, are discussed.
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
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
Annie E. Spikes; Matthew A. Paschen; Jocelyn G. Miller; Jardel A. Moreira; Paul B. Hamel; Nathan M. Schiff; Matthew D. Ginzel
Little is known of the reproductive behavior of longhorned beetles (Coleoptera: Cerambycidae) in the subfamily Prioninae. Mallodon dasystomus (Say), the hardwood stump borer, is a widely distributed prionine that is native to the southern U.S. Here, we explored the chemically-mediated mating behavior of M dasystomus, and tested the hypothesis that males recognize...
J.C. Nod; F.L. Hastings; A.S. Jones
An experimental mixture of terpene hydrocarbons derived from wood pulping, BBR-2, sprayed on the lower 6 m of widely separated southern pine trees did not protect nearby trees from southern pine beetle attacks. Whether treated trees were protected from southern pine beetle was inconclusive. The pine oil mixture did not repellpsfrom treated trees or nearby untreated...
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 (r2 from 0.18-0.60). 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 (r2=0.92). The discrepancy between methods of respiration estimation should be resolved to have confidence in ecosystem carbon flux estimates.
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
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.
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
René Alberto López Castilla; Fidel Góngora Rojas; Celia Guerra Rivero; Enrique de Zayas Izaguirre; Antonio Fernández Vera; Natividad Triguero Isasi
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 bigge...
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
Roč. 172, č. 2 (2018), s. 111-125 ISSN 0003-4746 R&D Projects: GA ČR(CZ) GJ16-15293Y Institutional support: RVO:61388971 Keywords : Bacterial pathogens * bacterial symbionts * beetle nutrition Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 2.046, year: 2016
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.,...
Bearup, Lindsay A; Mikkelson, Kristin M; Wiley, Joseph F; Navarre-Sitchler, Alexis K; Maxwell, Reed M; Sharp, Jonathan O; McCray, John E
Recent mountain pine beetle infestation in the Rocky Mountains of North America has killed an unprecedented acreage of pine forest, creating an opportunity to observe an active re-equilibration in response to widespread land cover perturbation. This work investigates metal mobility in beetle-impacted forests using parallel rainwater and acid leaches to estimate solid-liquid partitioning coefficients and a complete sequential extraction procedure to determine how metals are fractionated in soils under trees experiencing different phases of mortality. Geochemical model simulations analyzed in consideration with experimental data provide additional insight into the mechanisms controlling metal complexation. Metal and base-cation mobility consistently increased in soils under beetle-attacked trees relative to soil under healthy trees. Mobility increases were more pronounced on south facing slopes and more strongly correlated to pH under attacked trees than under healthy trees. Similarly, soil moisture was significantly higher under dead trees, related to the loss of transpiration and interception. Zinc and cadmium content increased in soils under dead trees relative to living trees. Cadmium increases occurred predominantly in the exchangeable fraction, indicating increased mobilization potential. Relative increases of zinc were greatest in the organic fraction, the only fraction where increases in copper were observed. Model results reveal that increased organic complexation, not changes in pH or base cation concentrations, can explain the observed differences in metal partitioning for zinc, nickel, cadmium, and copper. Predicted concentrations would be unlikely to impair human health or plant growth at these sites; however, higher exchangeable metals under beetle-killed trees relative to healthy trees suggest a possible decline in riverine ecosystem health and water quality in areas already approaching criteria limits and drinking water standards. Impairment of water
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
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
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.
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.
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.
Bearup, Lindsay A., E-mail: firstname.lastname@example.org [Department of Civil and Environmental Engineering, Colorado School of Mines, 1500 Illinois Street, Golden, CO 80401 (United States); Hydrological Science and Engineering Program, Colorado School of Mines, 1500 Illinois Street, Golden, CO 80401 (United States); Mikkelson, Kristin M. [Department of Civil and Environmental Engineering, Colorado School of Mines, 1500 Illinois Street, Golden, CO 80401 (United States); Hydrological Science and Engineering Program, Colorado School of Mines, 1500 Illinois Street, Golden, CO 80401 (United States); Wiley, Joseph F. [Department of Civil and Environmental Engineering, Colorado School of Mines, 1500 Illinois Street, Golden, CO 80401 (United States); Navarre-Sitchler, Alexis K.; Maxwell, Reed M. [Hydrological Science and Engineering Program, Colorado School of Mines, 1500 Illinois Street, Golden, CO 80401 (United States); Department of Geology and Geological Engineering, Colorado School of Mines, 1500 Illinois Street, Golden, CO 80401 (United States); Sharp, Jonathan O.; McCray, John E. [Department of Civil and Environmental Engineering, Colorado School of Mines, 1500 Illinois Street, Golden, CO 80401 (United States); Hydrological Science and Engineering Program, Colorado School of Mines, 1500 Illinois Street, Golden, CO 80401 (United States)
Recent mountain pine beetle infestation in the Rocky Mountains of North America has killed an unprecedented acreage of pine forest, creating an opportunity to observe an active re-equilibration in response to widespread land cover perturbation. This work investigates metal mobility in beetle-impacted forests using parallel rainwater and acid leaches to estimate solid–liquid partitioning coefficients and a complete sequential extraction procedure to determine how metals are fractionated in soils under trees experiencing different phases of mortality. Geochemical model simulations analyzed in consideration with experimental data provide additional insight into the mechanisms controlling metal complexation. Metal and base-cation mobility consistently increased in soils under beetle-attacked trees relative to soil under healthy trees. Mobility increases were more pronounced on south facing slopes and more strongly correlated to pH under attacked trees than under healthy trees. Similarly, soil moisture was significantly higher under dead trees, related to the loss of transpiration and interception. Zinc and cadmium content increased in soils under dead trees relative to living trees. Cadmium increases occurred predominantly in the exchangeable fraction, indicating increased mobilization potential. Relative increases of zinc were greatest in the organic fraction, the only fraction where increases in copper were observed. Model results reveal that increased organic complexation, not changes in pH or base cation concentrations, can explain the observed differences in metal partitioning for zinc, nickel, cadmium, and copper. Predicted concentrations would be unlikely to impair human health or plant growth at these sites; however, higher exchangeable metals under beetle-killed trees relative to healthy trees suggest a possible decline in riverine ecosystem health and water quality in areas already approaching criteria limits and drinking water standards. Impairment of
Sivanpillai, R.; Ewers, B. E.; Speckman, H. N.; Miller, S. N.
In the Western United States, more than 3 million hectares of lodgepole pine forests have been impacted by the Mountain pine beetle outbreak, while another 166,000 hectares of spruce-fir forests have been attacked by Spruce beetle. Following the beetle attack, the trees lose their hydraulic conductivity thus altering their carbon and water fluxes. These trees go through various stages of stress until mortality, described by color changes in their needles prior to losing them. Modeling the impact of these vegetation types require thematically precise land cover data that distinguishes lodgepole pine and spruce-fir forests along with the stage of impact since the ecosystem fluxes are different for these two systems. However, the national and regional-scale land cover datasets derived from remotely sensed data do not have this required thematic precision. We evaluated the feasibility of multispectral data collected by Landsat 8 to distinguish lodgepole pine and spruce fir, and subsequently model the different stages of attack using field data collected in Medicine Bow National Forest (Wyoming, USA). Operational Land Imager, onboard Landsat 8 has more spectral bands and higher radiometric resolution (12 bit) in comparison to sensors onboard earlier Landsat missions which could improve the ability to distinguish these vegetation types and their stress conditions. In addition to these characteristics, its repeat coverage, rigorous radiometric calibration, wide swath width, and no-cost data provide unique advantages to Landsat data for mapping large geographic areas. Initial results from this study highlight the importance of SWIR bands for distinguishing different levels of stress, and the need for ancillary data for distinguishing species types. Insights gained from this study could lead to the generation of land cover maps with higher thematic precision, and improve the ability to model various ecosystem processes as a result of these infestations.
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.
Frank, J. M.; Massman, W. J.
The GLEES-AmeriFlux site is located in the Snowy Range Mountains, Medicine Bow National Forest, southeastern Wyoming [41o21’52” N, 106o14’22” W; 3190 m MSL]. Since November 1999, measurements of surface energy balance, momentum, CO2, and water vapor eddy-covariance fluxes have been made at the subalpine site which is dominated by an Engelmann spruce (Picea engelmannii) and subalpine fir (Abies lasiocarpa) forest. An ongoing spruce beetle (Dendroctonus rufipennis) outbreak has caused significant tree mortality in the forest over the past few years. In this study we investigate the impact of this bark beetle epidemic on the net ecosystem exchange of carbon (NEE) and evapotranspiration (ET); to achieve this goal we quantify the impact of significant eddy-covariance measurement issues. From 2006 to 2009 the magnitude of NEE decreased steadily by an average of 0.8 MgC ha-1 yr-1, which resulted in the reduction of the annual C sink from 2.9 to 0.6 MgC ha-1 yr-1. Over this time ET decreased steadily from 72.2 to 58.3 cm yr-1. The importance of the Webb-Pearman-Leuning (WPL) correction due to self-heating associated with open-path CO2/H2O analyzers was quantified by applying a thermodynamic model based on (1) a generalized model for instrument surface temperatures and (2) measured and site-specific modeled surface temperatures. The increase in measured NEE (towards being a net C source) due to the generalized model (1) was 2.2 MgC ha-1 yr-1, while the site specific corrections (2) accounted for an increase of 2.8 MgC ha-1 yr-1. The self-heating correction was much less important with ET measurements, increasing the measured flux by 0.5 cm yr-1, regardless of which method of determining surface temperature was used.
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.
Ronald F Billings; William W. Upton
An operational system to forecast infestation trends (increasing, static, declining) and relative population levels (high, moderate, low) of the southern pine beetle (SPB), Dendroctonus frontalis, has been implemented in the Southern and Eastern United States. Numbers of dispersing SPB and those of a major predator (the clerid beetle, ...
Schlechter-Helas, Jerry; Schmitt, Thomas; Peschke, Klaus
By reducing the attractiveness of their mating partner via an anti-aphrodisiac pheromone, males can prevent a remating of the female and thus reduce the risk of sperm competition. For females, the main benefit from allowing the chemical manipulation of their attractiveness is probably the avoidance of sexual harassments from rival males. While mating plugs generally constitute a physical barrier which hinders male mating attempts, chemical manipulations must trustfully inform the responding male of the female's reluctance to mate; otherwise, it would be beneficial to ignore the repellent information. In our experiments, males of the polyandrous rove beetle Aleochara curtula chemically manipulated the attractiveness of their mating partner. Coincident with the deposition of a spermatophore into the female genital chamber, an anti-aphrodisiac pheromone was transferred and readily spread onto the female surface, where it was subsequently perceived by rival males via parameres, the claspers of the male genitalia. Males aborted contact with the mated female to avoid further time- and energy-consuming elements of the mating sequence. The chemical mode of action was demonstrated inter alia by spicing virgin females with spermatophore extracts. The action of the anti-aphrodisiac correlated with the persistence of the spermatophore in the female genital chamber and corresponded to the length of stay of the mated female at a carcass, where the density of rival males is highest. The ensuing benefits for all three parties involved in this communication system, which render this post-copulatory mate guarding strategy evolutionary stable, are discussed.
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.
König, Kerstin; Seeger, Lucy; Steidle, Johannes L M
Throughout the animal kingdom, sexual pheromones are used for the attraction of mates and as courtship signals but also enable sexual isolation between species. In the parasitic wasp Lariophagus distinguendus, male courtship behaviour consisting of wing fanning, antennal stroking of the female antenna, and head nodding stimulates female receptivity leading to copulation. Recently L. distinguendus was reported to consist of two different lineages, which are sexually isolated because males fail to elicit receptivity in foreign females. It is unclear, however, which part of the courtship behaviour triggers female receptivity and therefore could be a mechanism causing sexual isolation. Here we show that in L. distinguendus a nonvolatile male oral pheromone is essential to release the female receptivity signal. In contrast, male wing fanning and antennal contact play a minor role. Additionally, the composition of the oral pheromone depends on the developmental host and females learn the composition upon emergence from the host substrate. These results will enable more detailed work on oral sexual pheromones to answer the question of how they are involved in the speciation process of L. distinguendus and other parasitoid species, for a better understanding of the huge biodiversity in this group.
Full Text Available Throughout the animal kingdom, sexual pheromones are used for the attraction of mates and as courtship signals but also enable sexual isolation between species. In the parasitic wasp Lariophagus distinguendus, male courtship behaviour consisting of wing fanning, antennal stroking of the female antenna, and head nodding stimulates female receptivity leading to copulation. Recently L. distinguendus was reported to consist of two different lineages, which are sexually isolated because males fail to elicit receptivity in foreign females. It is unclear, however, which part of the courtship behaviour triggers female receptivity and therefore could be a mechanism causing sexual isolation. Here we show that in L. distinguendus a nonvolatile male oral pheromone is essential to release the female receptivity signal. In contrast, male wing fanning and antennal contact play a minor role. Additionally, the composition of the oral pheromone depends on the developmental host and females learn the composition upon emergence from the host substrate. These results will enable more detailed work on oral sexual pheromones to answer the question of how they are involved in the speciation process of L. distinguendus and other parasitoid species, for a better understanding of the huge biodiversity in this group.
Full Text Available Background Frequent outbreaks of insects and diseases have been recorded in the native forests of western North America during the last few decades, but the distribution of these outbreaks has been far from uniform. In some cases, recent climatic variations may explain some of this spatial variation along with the presence of expansive forests composed of dense, older trees. Forest managers and policy makers would benefit if areas especially prone to disturbance could be recognized so that mitigating actions could be taken. Methods We use two ponderosa pine-dominated sites in western Montana, U.S.A. to apply a modeling approach that couples information acquired via remote sensing, soil surveys, and local weather stations to assess where bark beetle outbreaks might first occur and why. Although there was a general downward trend in precipitation for both sites over the period between 1998 and 2010 (slope = −1.3, R2 = 0.08, interannual variability was high. Some years showed large increases followed by sharp decreases. Both sites had similar topography and fire histories, but bark beetle activity occurred earlier (circa 2000 to 2001 and more severely on one site than on the other. The initial canopy density of the two sites was also similar, with leaf area indices ranging between 1.7-2.0 m2·m−2. We wondered if the difference in bark beetle activity was related to soils that were higher in clay content at site I than at site II. To assess this possibility, we applied a process-based stand growth model (3-PG to analyze the data and evaluate the hypotheses. Results We found that when wet years were followed by drier years, the simulated annual wood production per unit of leaf area, a measure of tree vigor, dropped below a critical threshold on site I but not on site II. Conclusion We concluded that the difference in vulnerability of the two stands to beetle outbreaks can be explained largely by differences in gross photosynthesis
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...
Christopher J. Fettig; Kurt K. Allen; Robert R. Borys; John Christopherson; Christopher P. Dabney; Thomas J. Eager; Kenneth E. Gibson; Elizabeth G. Hebertson; Daniel F. Long; A. Steven Munson; Patrick J. Shea; Sheri L. Smith; Michael I. Haverty
High-value trees, such as those located in residential, recreational, or administrative sites, are particularly susceptible to bark beetle (Coleoptera: Curculionidae: Scolytinae) attack as a result of increased amounts of stress associated with drought, soil compaction, mechanical injury, or vandalism. Tree losses in these unique environments generally have a...
Rantala, Markus J; Jokinen, Ilmari; Kortet, Raine; Vainikka, Anssi; Suhonen, Jukka
Pheromones function not only as mate attractors, but they may also relay important information to prospective mates. It has been shown that vertebrates can distinguish, via olfactory mechanisms, major histocompatibility complex types in their prospective mates. However, whether pheromones can transmit information about immunocompetence is unknown. Here, we show that female mealworm beetles (Tenebrio molitor) prefer pheromones from males with better immunocompetence, indicated by a faster encapsulation rate against a novel antigen, and higher levels of phenoloxidase in haemolymph. Thus, the present study indicates that pheromones could transmit information about males' parasite resistance ability and may work as a reliable sexual ornament for female choice. PMID:12204128
Žunič Kosi, A.; Zou, Y.; Hoskovec, Michal; Vrezec, A.; Stritih, N.; Millar, J. G.
Roč. 12, č. 8 (2017), č. článku e0183279. E-ISSN 1932-6203 Institutional support: RVO:61388963 Keywords : 1758 Coleoptera Cerambycidae * host plant volatiles * sex pheromone Subject RIV: CC - Organic Chemistry OBOR OECD: Organic chemistry Impact factor: 2.806, year: 2016 http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0183279
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...
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
Hulcr, Jiří; Ubik, Karel; Vrkoč, Jan
Roč. 130, č. 5 (2006), s. 275-283 ISSN 0931-2048 R&D Projects: GA ČR GD206/03/H034 Institutional research plan: CEZ:AV0Z40550506; CEZ:AV0Z50070508 Keywords : monoterpenes * pheromones * semiochemicals * Medetera setiventris * Thanasimus Subject RIV: CC - Organic Chemistry Impact factor: 0.841, year: 2006
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...
Maurer, Gregory E; Chan, Allison M; Trahan, Nicole A; Moore, David J P; Bowling, David R
Bark beetle outbreaks are widespread in western North American forests, reducing primary productivity and transpiration, leading to forest mortality across large areas and altering ecosystem carbon cycling. Here the carbon isotope composition (δ(13) C) of soil respiration (δJ ) was monitored in the decade after disturbance for forests affected naturally by mountain pine beetle infestation and artificially by stem girdling. The seasonal mean δJ changed along both chronosequences. We found (a) enrichment of δJ relative to controls (soils in the first 2 years after disturbance; (b) depletion (1‰ or no change) during years 3-7; and (c) a second period of enrichment (1-2‰) in years 8-10. Results were consistent with isotopic patterns associated with the gradual death and decomposition of rhizosphere organisms, fine roots, conifer needles and woody roots and debris over the course of a decade after mortality. Finally, δJ was progressively more (13) C-depleted deeper in the soil than near the surface, while the bulk soil followed the well-established pattern of (13) C-enrichment at depth. Overall, differences in δJ between mortality classes (soil depths (<3‰) were smaller than variability within a class or depth over a season (up to 6‰). © 2016 The Authors. Plant, Cell and Environment published by John Wiley & Sons Ltd.
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...
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...
Hart, Adam G.
Pheromones are chemicals used to communicate with members of the same species. First described in insects, pheromones are often used to attract mates but in social insects, such as ants and bees, pheromone use is much more sophisticated. For example, ants use pheromones to make foraging trails and the chemical and physical properties of the…
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.
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....
Mikkelson, Kristin M; Brouillard, Brent M; Bokman, Chelsea M; Sharp, Jonathan O
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 NH 4 + 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. IMPORTANCE Forests around the world are succumbing to insect infestation with repercussions for local soil biogeochemistry and downstream water quality and quantity. This study utilized microbial community dynamics to address why we are observing watershed scale biogeochemical impacts from forest mortality in some impacted areas but not others. Through a unique "tree-centric" approach, we were able to delineate plots with various tree mortality levels within the same watershed
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.
Norton, U.; Pendall, E.; Ewers, B. E.; Borkhuu, B.
Severe outbreak of mountain pine beetle (MPB) and associated blue stain fungi have killed millions of hectares of coniferous forests in Western North America. This unprecedented disturbance has critically impacted ecosystem biogeochemistry and net carbon (C) and nitrogen (N) fluxes. However, the effects on greenhouse gas (GHG) emissions and drivers of biogeochemical processes that trigger GHG emissions following MPB infestations are not well understood. Such information can help assess regional-level changes in ecosystem C and N budgets and large-scale disturbance impacts on gas exchange between the atmosphere and terrestrial ecosystem. The overall objective of this research was to assess the immediate responses of GHG fluxes and soil C and N mineralization rates along a chronosequence of recently infested (1-yr, 3-yr and 4-yr ago) and uninfested (150-yr, 20-yr and 15-yr old) lodgepole pine stands in Medicine Bow National Forest in southeastern Wyoming. We hypothesize that MPB-induced tree mortality significantly changes stand-level hydrology, soil organic matter quality and chemistry of aboveground and belowground plant inputs. Consequently, these modifications influence nitrous oxide (N2O) emissions and methane (CH4) assimilation. Biweekly GHG measurements using static chambers were carried out during three consecutive snow-free growing seasons. Our results suggest that a stand infested within a year already shows a 20% increase in spring N2O production and a small decline in summer CH4 assimilation when compared to uninfested stands. Stands infested three and four years prior to our measurements produce over three times more N2O and assimilate three to five times less CH4 when compared to uninfested stands. In addition, a notable increase in soil moisture content and soil mineral N concentrations following early onset of the MPB infestation was also observed. An overall increase in N2O production and decline in CH4 assimilation following MPB infestation may
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 (water stress. The model is able to capture this relatively small decline in NSC by limiting NSC utilization through loss of plant hydraulic
R.A. Progar; N. Sturdevant; M.J. Rinella
Douglas-fir beetle (Dendroctonus pseudotsugae Hopkins) (DFB) causes considerable mortality to Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) in western North American forests. We evaluated the use of semiochemical-baited multiple-funnel traps for the protection of small, high-value stands of trees, such as those occurring...
Full Text Available The number of Ips typographus generations developed in a year might be indicative of its population size and of risk to Norway spruce forests. Warm weather and unremoved fallen trees after natural disturbances are thought of as key factors initiating large population increase. We studied I. typographus development in a spruce forest of the Tatra National Park, which was heavily affected by large-scale disturbances in the last decade. Repeated windthrows and consequent bark beetle outbreaks have damaged almost 20,000 hectares of mature Norway spruce forests, what is a half of the National Park forest area. Current I. typographus population size and its response to the environment and to forestry defense measures attract attention of all stakeholders involved in natural resource management, including public. In this paper we analyse the potential I. typographus population size in two consecutive years 2014 and 2015, which represented a climatologically normal year and an extremely hot year, respectively. We used bark temperature and phenology models to estimate the number of generations developed in each year. In 2014, the average bark temperature of standing living trees at study sites was 14.5 °C, in 2015 it increased to 15.7 °C. The bark temperature of fallen logs was 17.7 °C in 2014, and 19.5 °C in 2015. The bark temperature of standing living trees allowed to develop one and two generations in 2014 and 2015, respectively. The elevated bark temperature of fallen logs allowed to develop two generations in 2014 and three generations in 2015. The good match between the predicted and observed timing of each generation emergence as well as the large increase in the number of catches in pheromone traps in 2015 indicated a dramatic increase of the I. typographus population in the extremely warm year, especially at the unmanaged windthrown site.
Group-living species produce signals that alter the behavior and even the physiology of their social partners. Social insects possess especially sophisticated chemical communication systems that govern every aspect of colony life, including the defining feature of eusociality: reproductive division of labor. Current evidence hints at the central importance of queen pheromones, but progress has been hindered by the fact that such pheromones have only been isolated in honeybees. In a pair of papers on the ant Lasius niger, we identified and investigated a queen pheromone regulating worker sterility. The cuticular hydrocarbon 3-methylhentriacontane (3-MeC31) is correlated with queen maturity and fecundity and workers are also more likely to execute surplus queens that have low amounts of this chemical. Experiments with synthetic 3-MeC31 found that it inhibits ovarian development in queenless workers and lowers worker aggression towards objects coated with it. Production of 3-MeC31 by queens was depressed by an experimental immune challenge, and the same chemical was abundant on queenlaid eggs, suggesting that the workers' responses to the queen are conditional on her health and fecundity. Together with other studies, these results indicate that queen pheromones are honest signals of quality that simultaneously regulate multiple social behaviors. PMID:21331238
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
Gillette, Nancy E; Mehmel, Constance J; Mori, Sylvia R; Webster, Jeffrey N; Wood, David L; Erbilgin, Nadir; Owen, Donald R
In an attempt to improve semiochemical-based treatments for protecting forest stands from bark beetle attack, we compared push-pull versus push-only tactics for protecting lodgepole pine (Pinus contorta Douglas ex Loudon) and whitebark pine (Pinus albicaulis Engelm.) stands from attack by mountain pine beetle (Dendroctonus ponderosae Hopkins) in two studies. The first was conducted on replicated 4.04-ha plots in lodgepole pine stands (California, 2008) and the second on 0.81-ha plots in whitebark pine stands (Washington, 2010). In both studies, D. ponderosae population levels were moderate to severe. The treatments were 1) push-only (D. ponderosae antiaggregant semiochemicals alone); 2) push-pull (D. ponderosae antiaggregants plus perimeter traps placed at regular intervals, baited with four-component D. ponderosae aggregation pheromone); and 3) untreated controls. We installed monitoring traps baited with two-component D. ponderosae lures inside each plot to assess effect of treatments on beetle flight. In California, fewer beetles were collected in push-pull treated plots than in control plots, but push-only did not have a significant effect on trap catch. Both treatments significantly reduced the rate of mass and strip attacks by D. ponderosae, but the difference in attack rates between push-pull and push-only was not significant. In Washington, both push-pull and push-only treatments significantly reduced numbers of beetles caught in traps. Differences between attack rates in treated and control plots in Washington were not significant, but the push-only treatment reduced attack rates by 30% compared with both the control and push-pull treatment. We conclude that, at these spatial scales and beetle densities, push-only may be preferable for mitigating D. ponderosae attack because it is much less expensive, simpler, and adding trap-out does not appear to improve efficacy.
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-...
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...
Atterholt, C A; Delwiche, M J; Rice, R E; Krochta, J M
Paraffin wax and aqueous paraffin emulsions can be used as controlled release carriers for insect sex pheromones for mating disruption of orchard pests. Paraffin can be applied at ambient temperature as an aqueous emulsion, adheres to tree bark or foliage, releases pheromone for an extended period of time, and will slowly erode from bark and biodegrade in soil. Pheromone emulsions can be applied with simple spray equipment. Pheromone release-rates from paraffin were measured in laboratory flow-cell experiments. Pheromone was trapped from an air stream with an adsorbent, eluted periodically, and quantified by gas chromatography. Pheromone release from paraffin was partition-controlled, providing a constant (zero-order) release rate. A typical paraffin emulsion consisted of 30% paraffin, 4% pheromone, 4% soy oil, 1% vitamin E, 2% emulsifier, and the balance water. Soy oil and vitamin E acted as volatility suppressants. A constant release of oriental fruit moth pheromone from paraffin emulsions was observed in the laboratory for more than 100 days at 27 degreesC, with release-rates ranging from 0.4 to 2 mg/day, depending on the concentration and surface area of the dried emulsion. The use of paraffin emulsions is a viable method for direct application of insect pheromones for mating disruption. Sprayable formulations can be designed to release insect pheromones to the environment at a rate necessary for insect control by mating disruption. At temperatures below 38 degreesC, zero-order release was observed. At 38 degreesC and higher, pheromone oxidation occurred. A partition-controlled release mechanism was supported by a zero-order pheromone release-rate, low air/wax partition coefficients, and pheromone solubility in paraffin.
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.
... 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 ...
Clark, Erin L; Pitt, Caitlin; Carroll, Allan L; Lindgren, B Staffan; Huber, Dezene P W
The mountain pine beetle, Dendroctonus ponderosae, is a significant pest of lodgepole pine in British Columbia (BC), where it has recently reached an unprecedented outbreak level. Although it is native to western North America, the beetle can now be viewed as a native invasive because for the first time in recorded history it has begun to reproduce in native jack pine stands within the North American boreal forest. The ability of jack pine trees to defend themselves against mass attack and their suitability for brood success will play a major role in the success of this insect in a putatively new geographic range and host. Lodgepole and jack pine were sampled along a transect extending from the beetle's historic range (central BC) to the newly invaded area east of the Rocky Mountains in north-central Alberta (AB) in Canada for constitutive phloem resin terpene levels. In addition, two populations of lodgepole pine (BC) and one population of jack pine (AB) were sampled for levels of induced phloem terpenes. Phloem resin terpenes were identified and quantified using gas chromatography. Significant differences were found in constitutive levels of terpenes between the two species of pine. Constitutive α-pinene levels - a precursor in the biosynthesis of components of the aggregation and antiaggregation pheromones of mountain pine beetle - were significantly higher in jack pine. However, lower constitutive levels of compounds known to be toxic to bark beetles, e.g., 3-carene, in jack pine suggests that this species could be poorly defended. Differences in wounding-induced responses for phloem accumulation of five major terpenes were found between the two populations of lodgepole pine and between lodgepole and jack pine. The mountain pine beetle will face a different constitutive and induced phloem resin terpene environment when locating and colonizing jack pine in its new geographic range, and this may play a significant role in the ability of the insect to persist in
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,
Full Text Available ABSTRACT Pheromones are chemicals produced as liquids by specialised cells or glands and transmitted into the environment as liquids or gases. In contrary to hormones, which are excreted in organism and have effect exclusively on organism that produced them, pheromones are excreted outside organism and effect on different individuals of the same species. Pheromones mediate nearly all aspects of honeybee colony life including social defence, brood care, mating, orientation, foraging and reproduction. Pheromone investigation has high economic importance. With use of pheromones it is possible to manipulate with pest insects on crops or to direct honeybees during pollination on target plants.
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.
Erin L. Clark
Full Text Available The mountain pine beetle, Dendroctonus ponderosae, is a significant pest of lodgepole pine in British Columbia (BC, where it has recently reached an unprecedented outbreak level. Although it is native to western North America, the beetle can now be viewed as a native invasive because for the first time in recorded history it has begun to reproduce in native jack pine stands within the North American boreal forest. The ability of jack pine trees to defend themselves against mass attack and their suitability for brood success will play a major role in the success of this insect in a putatively new geographic range and host. Lodgepole and jack pine were sampled along a transect extending from the beetle’s historic range (central BC to the newly invaded area east of the Rocky Mountains in north-central Alberta (AB in Canada for constitutive phloem resin terpene levels. In addition, two populations of lodgepole pine (BC and one population of jack pine (AB were sampled for levels of induced phloem terpenes. Phloem resin terpenes were identified and quantified using gas chromatography. Significant differences were found in constitutive levels of terpenes between the two species of pine. Constitutive α-pinene levels – a precursor in the biosynthesis of components of the aggregation and antiaggregation pheromones of mountain pine beetle – were significantly higher in jack pine. However, lower constitutive levels of compounds known to be toxic to bark beetles, e.g., 3-carene, in jack pine suggests that this species could be poorly defended. Differences in wounding-induced responses for phloem accumulation of five major terpenes were found between the two populations of lodgepole pine and between lodgepole and jack pine. The mountain pine beetle will face a different constitutive and induced phloem resin terpene environment when locating and colonizing jack pine in its new geographic range, and this may play a significant role in the ability of the
Erbilgin, Nadir; Ma, Cary; Whitehouse, Caroline; Shan, Bin; Najar, Ahmed; Evenden, Maya
Host plant secondary chemistry can have cascading impacts on host and range expansion of herbivorous insect populations. We investigated the role of host secondary compounds on pheromone production by the mountain pine beetle (Dendroctonus ponderosae) (MPB) and beetle attraction in response to a historical (lodgepole pine, Pinus contorta var. latifolia) and a novel (jack pine, Pinus banksiana) hosts, as pheromones regulate the host colonization process. Beetles emit the same pheromones from both hosts, but more trans-verbenol, the primary aggregation pheromone, was emitted by female beetles on the novel host. The phloem of the novel host contains more α-pinene, a secondary compound that is the precursor for trans-verbenol production in beetle, than the historical host. Beetle-induced emission of 3-carene, another secondary compound found in both hosts, was also higher from the novel host. Field tests showed that the addition of 3-carene to the pheromone mixture mimicking the aggregation pheromones produced from the two host species increased beetle capture. We conclude that chemical similarity between historical and novel hosts has facilitated host expansion of MPB in jack pine forests through the exploitation of common host secondary compounds for pheromone production and aggregation on the hosts. Furthermore, broods emerging from the novel host were larger in terms of body size. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.
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...
Robert M. Hubbard; Charles C. Rhoades; Kelly Elder; Jose Negron
The recent mountain pine beetle outbreak in North American lodgepole pine forests demonstrates the importance of insect related disturbances in changing forest structure and ecosystem processes. Phloem feeding by beetles disrupts transport of photosynthate from tree canopies and fungi introduced to the tree's vascular system by the bark beetles inhibit water...
Andrus, Robert A; Veblen, Thomas T; Harvey, Brian J; Hart, Sarah J
Recent large and severe outbreaks of native bark beetles have raised concern among the general public and land managers about potential for amplified fire activity in western North America. To date, the majority of studies examining bark beetle outbreaks and subsequent fire severity in the U.S. Rocky Mountains have focused on outbreaks of mountain pine beetle (MPB; Dendroctonus ponderosae) in lodgepole pine (Pinus contorta) forests, but few studies, particularly field studies, have addressed the effects of the severity of spruce beetle (Dendroctonus rufipennis Kirby) infestation on subsequent fire severity in subalpine Engelmann spruce (Picea engelmannii) and subalpine fir (Abies lasiocarpa) forests. In Colorado, the annual area infested by spruce beetle outbreaks is rapidly rising, while MPB outbreaks are subsiding; therefore understanding this relationship is of growing importance. We collected extensive field data in subalpine forests in the eastern San Juan Mountains, southwestern Colorado, USA, to investigate whether a gray-stage (fire) spruce beetle infestation affected fire severity. Contrary to the expectation that bark beetle infestation alters subsequent fire severity, correlation and multivariate generalized linear regression analysis revealed no influence of pre-fire spruce beetle severity on nearly all field or remotely sensed measurements of fire severity. Findings were consistent across moderate and extreme burning conditions. In comparison to severity of the pre-fire beetle outbreak, we found that topography, pre-outbreak basal area, and weather conditions exerted a stronger effect on fire severity. Our finding that beetle infestation did not alter fire severity is consistent with previous retrospective studies examining fire activity following other bark beetle outbreaks and reiterates the overriding influence of climate that creates conditions conducive to large, high-severity fires in the subalpine zone of Colorado. Both bark beetle outbreaks and
Christopher J. Fettig; Donald M. Grosman; A. Steven. 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 have examined the effectiveness of...
Larsson, Mattias C; Hedin, Jonas; Svensson, Glenn P; Tolasch, Till; Francke, Wittko
Osmoderma eremita (Scopoli) is an endangered scarab beetle living in hollow trees. It has mainly been known for its characteristic odor, typically described as a fruity, peachlike or plumlike aroma. The odor emanating from a single beetle can sometimes be perceived from a distance of several meters. In this paper, we show that the characteristic odor from O. eremita is caused by the compound (R)-(+)-gamma-decalactone, released in large quantities mainly or exclusively by male beetles. Antennae from male and female beetles responded in a similar way to (R)-(+)-gamma-decalactone in electroantennographic recordings. Field trapping experiments showed that (R)-(+)-gamma-decalactone is a pheromone attracting female beetles. Lactones similar to (R)-(+)-gamma-decalactone are frequently used as female-released sex pheromones by phytophagous scarabs. This is, however, the first evidence of a lactone used as a male-produced pheromone in scarab beetles. We propose that the strong signal from males is a sexually selected trait used to compete for females and matings. The signal could work within trees but also act as a guide to tree hollows, which are an essential resource for O. eremita. Males may, thus, attract females dispersing from their natal tree by advertising a suitable habitat. This signal could also be exploited by other males searching for tree hollows or for females, which would explain the catch of several males in our traps.
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.
Hodgson, Erin W.; Patterson, Ron
There are many beneficial beetles in Utah besides lady beetles or ladybugs. Beetles can significantly reduce common insect and weed problems and in some cases eliminate the need for chemical control. Examples of beneficial beetles include: ground beetles, rove beetles, tiger beetles and tortoise beetles. Many of these beetles are native to Utah, while others have been purposely introduced to help control damage from exotic insect and weed pests.
Brice A. McPherson; Nadir Ebilgin; David L. Wood; Pavel Svihra; Andrew J. Storer; Richard B. Standiford
Saprotro phic ambrosia and bark beetles (Coleoptera: Scolytidae) tunnel into the bark overlying cankers caused by Phytophthora ramorum in coast live oaks, Quercus agrifolia. These insects are characteristically reported to colonize freshly dead or moribund trees (Furniss and Carolin, 1977). However, the initial attacks by these...
Rick G. Kelsey; Maia Beh; Dave Shaw; Daniel K. Manter
Successful infection of coast live oak (Quercus agrifolia NÃ©e) stems by Phytophthora ramorum results in the formation of a canker visible initially at the bark surface by the release of a dark red to black colored exudate referred to as "bleeding." Bark and ambrosia beetles are often attracted to diseased trees within...
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...
Jacob M. Griffin; Monica G. Turner; Martin Simard
Widespread bark beetle outbreaks are currently affecting multiple conifer forest types throughout western North America, yet many ecosystem-level consequences of this disturbance are poorly understood. We quantified the effect of mountain pine beetle (Dendroctonus ponderosae) outbreak on nitrogen (N) cycling through litter, soil, and vegetation in...
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,...
S. A. Mata; J. M. Schmid; D. A. Leatherman
Diesel fuel oil was applied to mountain pine beetle (Dendroctonus ponderosae Hopkins) infested bolts of ponderosa pine (Pinus ponderosa Lawson) in early June. Just prior to the fuel oil application and 6 weeks later, 0.5 ft2 bark samples were removed from each bolt and the numbers of live beetles counted....
Byzov, V I; Trestsov, A B
A brief review of possible uses of the 130,000 cubic meters of bark produced annually by mills in the Mari ASSR. Present uses include tar production from birch bark and tannins from spruce bark. Several uses are suggested that require little capital expenditure: infill of roads, gullies etc.; fertilizers for market gardens and orchards; and bark/cement slabs. The manufacture is described of a new bark/cement slab suitable for low buildings, that uses milled green bark of spruce and pine.
Hasni, Narjes; Pinier, Centina; Imed, Cheraief; Ouhichi, Monêem; Couzi, Philippe; Chermiti, Brahim; Frérot, Brigitte; Saïd, Imen; Rochat, Didier
Laboratory and field investigations to identify and evaluate plant co-attractants of the aggregation pheromone of the date palm pest Oryctes agamemnon are reported. Volatiles emitted by freshly cut palm core and palm core with feeding males, were collected, analyzed by gas chromatography coupled to mass spectrometry and evaluated in olfactometers alone or combined with synthetic pheromone. A collection of palm odor without male effluvia was attractive alone and enhanced attraction to synthetic pheromone in an olfactometer similar to that to a collection of palm odor emitted with feeding males and containing natural pheromone. Behavioral responses to collections of palm volatiles were correlated to the amount of volatiles material in them. Enhancement of the attractiveness of the pheromone was not correlated to chemicals specific to beetle feeding. The chemicals common to the active collections extracts were benzoate esters, mostly ethyl benzoate, anisole derivatives and sesquiterpenes. Blends of the most abundant components of the extracts were evaluated for enhancement of the attractiveness of pheromone (1 μg) in olfactometers at 1 or 10 μg doses. The mixtures were further evaluated by field trapping in Tunisia at 3-10 mg/day using reference (6 mg/day) or experimental pheromone formulations. A mixture of ethyl benzoate, 4-methylanisole and farnesol (1:1:1 w/w at 6.5 mg/day) enhanced captures in pheromone baited traps in 2014 and 2015 and this mixture was as active as the natural palm bait. The practical prospect of the result for the management for O. agamemnon, and other palm beetles is discussed.
Mating behaviour in the yellow mealworm beetle, Tenebrio molitor , is mediated by several pheromones, including the female-produced 4-methylnonanol (4-MNol). Mating causes a decline in the titre of 4-MNol. The overall goal of this study was to determine the biochemical mechanism(s) responsible for this decline: i.e., whether the decline was due to an inhibition of pheromone biosynthesis and/or a stimulation of pheromone degradation; whether the decline was caused by the physical effect of mating or was due to the transfer of a factor from the male; and to conduct a preliminary investigation of the regulatory and signal transduction mechanisms involved in the regulation of 4-MNol production. In vitro radioassays for 4-MNol biosynthesis and degradation were developed and used to compare the levels of 4-MNol biosynthesis and degradation in virgin and mated females. Mating caused an inhibition of 4-MNol biosynthesis within 2 hours, but did not affect the rate of pheromone degradation. Decapitation of virgin females caused an inhibition of pheromone biosynthesis and did not prevent the inhibitory effect of mating. The inhibitory effect of mating was mimicked in females that were artificially inseminated with male reproductive tract homogenates (MRTH), but not in females similarly "inseminated" with water, saline, or air. Furthermore, 4-MNol biosynthesis could be inhibited in vitro by the addition of MRTH. These findings indicate that the male transferred one or more pheromonostatic factor(s) to the female during copulation that acted directly on the pheromone-producing tissue (the ovaries). In order to investigate the biochemical basis for the inhibition of pheromone biosynthesis after mating, the role of calcium was determined by modulating the level of calcium (using a calcium chelator, an ionophore, and calcium). However, due to the precipitation of calcium with the phosphate present in the buffer solution, we were unable to determine the role of calcium in the
Holdcraft, Robert; Rodriguez-Saona, Cesar; Stelinski, Lukasz L.
Olfactory communication research with insects utilizing sex pheromones has focused on the effects of pheromones on signal receivers. Early pheromone detection studies using the silkworm moth, Bombyx mori L., and Saturniids led to the assumption that emitters, especially females, are unable to detect their own pheromone. Pheromone anosmia, i.e., the inability of females to detect their conspecific sex pheromone, was often assumed, and initially little attention was paid to female behaviors that may result from autodetection, i.e., the ability of females to detect their sex pheromone. Detection of conspecific pheromone plumes from nearby females may provide information to improve chances of mating success and progeny survival. Since the first documented example in 1972, numerous occurrences of autodetection have been observed and verified in field and laboratory studies. We summarize here a significant portion of research relating to autodetection. Electrophysiological and behavioral investigations, as well as expression patterns of proteins involved in pheromone autodetection are included. We discuss problems inherent in defining a boundary between sex and aggregation pheromones considering the occurrence of autodetection, and summarize hypothesized selection pressures favoring autodetection. Importance of including autodetection studies in future work is emphasized by complications arising from a lack of knowledge combined with expanding the use of pheromones in agriculture. PMID:27120623
Christopher J. Fettig; Stepehen R. McKelvey; Christopher P. Dabney; Robert R. Borys
The red turpentine beetle, Dendroctonus valens LeConte, 1860 (Coleoptera: Curculionidae, Scolytinae), is a common bark beetle species found throughout much of North America and China. In 2004, we observed that California fivespined ips, Ips paraconfusus Lanier, 1970 (Coleoptera: Curculionidae, Scolytinae), attack densities in logging debris were inversely related to D...
Ray, A M; Swift, I P; Moreira, J A; Millar, J G; Hanks, L M
We report the identification and field bioassays of a major component of the male-produced aggregation pheromone of Anelaphus inflaticollis Chemsak, an uncommon desert cerambycine beetle. Male A. inflaticollis produced a sex-specific blend of components that included (R)-3-hydroxyhexan-2-one, (S)-2-hydroxyhexan-3-one, 2,3-hexanedione, and (2R,3R)- and (2R,3S)-2,3-hexanediols. Field trials with baited bucket traps determined that the reconstructed synthetic pheromone blend and (R)-3-hydroxyhexan-2-one alone attracted adult A. inflaticollis of both sexes, with significantly more beetles being attracted to the blend. We conclude that (R)-3-hydroxyhexan-2-one is a major pheromone component of A. inflaticollis, and our results suggest that one or more of the minor components may further increase attraction of conspecifics. Scanning electron microscopy showed that male A. inflaticollis have pores on the prothorax that are consistent in structure with sex-specific pheromone gland pores in related species. Males also displayed stereotyped calling behavior similar to that observed in other cerambycine species. This study represents the first report of volatile pheromones for a cerambycine species in the tribe Elaphidiini.
Frances S. Ockels; Pierluigi Bonello; Brice McPherson; David L. Wood
Coast live oaks, Quercus agrifolia, infected with Phytophthora ramorum in California produce a characteristic sequence of symptoms and signs. Ambrosia beetles consistently tunnel into the bark of bleeding cankers in naturally infected trees. In field monitoring conducted since 2000, every bleeding coast live oak that subsequently...
Full Text Available Many exocrine products used by ground beetles are pheromones and allomones that regulate intra- and interspecific interactions and contribute to their success in terrestrial ecosystems. This mini-review attempts to unify major themes related to the exocrine glands of carabid beetles. Here we report on both glandular structures and the role of secretions in carabid adults, and that little information is available on the ecological significance of glandular secretions in pre-imaginal stages.
Giglio, Anita; Brandmayr, Pietro; Talarico, Federica; Brandmayr, Tullia Zetto
Many exocrine products used by ground beetles are pheromones and allomones that regulate intra- and interspecific interactions and contribute to their success in terrestrial ecosystems. This mini-review attempts to unify major themes related to the exocrine glands of carabid beetles. Here we report on both glandular structures and the role of secretions in carabid adults, and that little information is available on the ecological significance of glandular secretions in pre-imaginal stages.
Robert J. Bartelt; John F. Kyhl; Angie K. Ambourn; Jennifer Juzwik; Steven J. Seybold
Carpophilus sayi, a nitidulid beetle vector of the oak wilt fungus, Ceratocystis fagacearum, was shown to have a male-produced aggregation pheromone. Six male-specific chemicals were identified from collections of volatiles. The two major compounds were (2E,4E,6E,8E)-3,5-dimethyl-7-ethyl-2,4,6,8- undecatetraene and (2E,4E,6E,8E...
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...
Nancy E. Gillette; Constance J. Mehmel; Sylvia R. Mori; Jeffrey N. Webster; David L. Wood; Nadir Erbilgin; Donald R. Owen
In an attempt to improve semiochemical-based treatments for protecting forest stands from bark beetle attack, we compared push-pull versus push-only tactics for protecting lodgepole pine (Pinus contorta Douglas ex Loudon) and whitebark pine (Pinus albicaulis Engelm.) stands from attack by mountain pine beetle (...
Haiganoush K. Preisler; Jeffrey A. Hicke; Alan A. Ager; Jane L. Hayes
Widespread outbreaks of mountain pine beetle in North America have drawn the attention of scientists, forest managers, and the public. There is strong evidence that climate change has contributed to the extent and severity of recent outbreaks. Scientists are interested in quantifying relationships between bark beetle population dynamics and trends in climate. Process...
Elise Pendall; Brent Ewers; Urszula Norton; Paul Brooks; W. J. Massman; Holly Barnard; David Reed; Tim Aston; John Frank
Conifer forests across western North America are undergoing a widespread mortality event mediated by an epidemic outbreak of bark beetles of the genus Dendroctonus and their associated bluestain fungi (Ophiostoma spp.). As of late 2009, beetles have impacted over 600,000 hectares in northern Colorado and southern Wyoming (US Forest Service aerial survey estimates),...
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...
David R. Houston; James T. O' Brien
Beech bark disease causes significant mortality and defect in American beech, Fagus grandifolia (Ehrh.). The disease results when bark, attacked and altered by the beech scale, Cryptococcus fagisuga Lind., is invaded and killed by fungi, primarily Nectria coccinea var. faginata Lohman, Watson, and Ayers, and sometimes N. galligena Bres.
J.J. Karchesy; R.W. Hemingway
The inner bark of Pinus taeda L. contains (+)-catechin, the procyanidin 8.1 (a C-4 to C-8 linked (-)-epicatechin to (+)-catechin dimer), and three polymeric procyanidins that have distinctly different solubility and chromatographic properties. An ethyl acetate soluble polymer (0.20% of bark, Mn = 1200) was purified by chromatography on LH-20 Sephadex. A water-soluble...
Chris J. Peterson; Sheryl L. Costello
Lodgepole and ponderosa pine trees were treated with a 2% carbaryl solution at recreational areas near Fort Collins, CO, in June 2010 as a prophylactic bole spray against the mountain pine beetle. Bark samples from treated and untreated trees were collected one day following application and at 4-month intervals for one year. The residual amount of carbaryl was...
Van Oystaeyen, Annette; van Zweden, Jelle S; Huyghe, Hilde; Drijfhout, Falko; Bonckaert, Wim; Wenseleers, Tom
The parasitoid beetle Metoecus paradoxus frequently parasitizes colonies of the common wasp, Vespula vulgaris. It penetrates a host colony as a larva that attaches itself onto a foraging wasp's body and, once inside the nest, it feeds on a wasp larva inside a brood cell and then pupates. Avoiding detection by the wasp host is crucial when the beetle emerges. Here, we tested whether adult M. paradoxus beetles avoid detection by mimicking the cuticular hydrocarbon profile of their host. The beetles appear to be chemically adapted to their main host species, the common wasp, because they share more hydrocarbon compounds with it than they do with the related German wasp, V. germanica. In addition, aggression tests showed that adult beetles were attacked less by common wasp workers than by German wasp workers. Our results further indicated that the host-specific compounds were, at least partially, produced through recycling of the prey's hydrocarbons, and were not acquired through contact with the adult host. Moreover, the chemical profile of the beetles shows overproduction of the wasp queen pheromone, nonacosane (n-C29), suggesting that beetles might mimic the queen's pheromonal bouquet.
Lord, Kathryn; Feinstein, Mark; Coppinger, Raymond
Barking is most often associated with the domestic dog Canis familiaris, but it is a common mammalian and avian vocalization. Like any vocalization, the acoustic character of the bark is likely to be a product of adaptation as well as an expression of the signaler's internal motivational state. While most authors recognize that the bark is a distinct signal type, no consistent description of its acoustic definition or function is apparent. The bark exhibits considerable variability in its acoustic form and occurs in a wide range of behavioral contexts, particularly in dogs. This has led some authors to suggest that dog barking might be a form of referential signaling, or an adaptation for heightened capability to communicate with humans. In this paper we propose a general 'canonical' acoustic description of the bark. Surveying relevant literature on dogs, wild canids, other mammals and birds, we explore an alternative functional hypothesis, first suggested by [Morton, E.S., 1977. On the occurrence and significance of motivation-structural rules in some bird and mammal sounds. Am. Nat. 111, 855-869] and consistent with his motivational-structural rules theory: that barking in many animals, including the domestic dog, is associated with mobbing behavior and the motivational states that accompany mobbing.
Ugine, Todd A; Gardescu, Sana; Lewis, Phillip A; Hajek, Ann E
Feeding experiments with Asian longhorned beetles (Anoplophora glabripennis (Motschulsky)) in a quarantine laboratory were used to assess the effectiveness of imidacloprid in reducing adult fecundity and survival. The beetles were fed twigs and leaves cut between June-September 2010 from Norway maples (Acer platanoides L.) in the beetle-infested area of Worcester, MA. Treated trees had been trunk-injected once with imidacloprid in spring 2010 under the U.S. Department of Agriculture-Animal and Plant Health Inspection Service operational eradication program. The 21 d LC50 value for adult beetles feeding on twig bark from imidacloprid-injected trees was 1.3 ppm. Adult reproductive output and survival were significantly reduced when beetles fed on twig bark or leaves from treated trees. However, results varied widely, with many twig samples having no detectable imidacloprid and little effect on the beetles. When twigs with > 1 ppm imidacloprid in the bark were fed to mated beetles, the number of larvae produced was reduced by 94% and median adult survival was reduced to 14 d. For twigs with 1 ppm). When given a choice of control twigs and twigs from injected trees, beetles did not show a strong preference.
Steven J. Seybold; Andrew D. Graves; Tom W. Coleman
The walnut twig beetle, Pityophthorus juglandis Blackman (Coleoptera: Scolytidae) (sensu Wood 2007), is a native North American bark beetle that has been recently implicated as the vector of thousand cankers disease of walnut trees in the western U.S. (Tisserat et al. 2009, Utley et al. 2009, Seybold et al. 2010).
Chad M. Hoffman; Penelope Morgan; William Mell; Russell Parsons; Eva Strand; Steve. Cook
Recent bark beetle outbreaks have had a significant impact on forests throughout western North America and have generated concerns about interactions and feedbacks between beetle attacks and fire. However, research has been hindered by a lack of experimental studies and the use of fire behavior models incapable of accounting for the heterogeneous fuel complexes. We...
of bark provides a waterproof layer on which water drops contain- ing fungal spores ..... Grey squirrel (Sciurus carolinensis and S. griseus), red squir- rel (S. vulgaris ... cotton (Abroma angustum) is useful in treatment of gynaecological ailments.
Chemnitz, Johanna; Bagrii, Nadiia; Ayasse, Manfred; Steiger, Sandra
Life history theory predicts a trade-off between male sexual trait expression and immunocompetence. Using burying beetles, Nicrophorus vespilloides, as a model, we investigated the relationship between male immune function, sex pheromone emission, and attractiveness under field conditions. In the first experiment, we tested whether there is a positive correlation between immune capacity, sex pheromone characteristics (quantity, relative composition, and time invested in pheromone emission), and male attractiveness. As a measurement of immune capacity, we used an individual's encapsulation ability against a novel antigen. In the second experiment, we specifically examined whether a trade-off between chemical trait expression and immune function existed. To this end, we challenged the immune system and measured the subsequent investment in sex pheromone emission and the attractiveness of the male under field conditions. We found that a male's immunocompetence was neither related to the emission of the male's sex pheromone nor to its attractiveness in the field. Furthermore, none of the immune-challenge treatments affected the subsequent investment in pheromone emission or number of females attracted. However, we showed that the same males that emitted a high quantity of their sex pheromone in the laboratory were able to attract more females in the field. Our data suggest that the chemical signal is not a reliable predictor of a male's immunocompetence but rather is a general important fitness-related trait, with a higher emission of the sex pheromone measured in the laboratory directly affecting the attractiveness of a male under field conditions.
The purpose of this symposium was to provide a forum where a variety of scientists who were interested in the interactions of insecticides and pheromones with the nervous system got together to exchange their views...
Heroldová, Marta; Jánová, Eva; Suchomel, J.; Purchart, L.; Homolka, Miloslav
Roč. 2, č. 2 (2009), s. 137-140 ISSN 1803-2451 R&D Projects: GA MZe QH72075 Institutional research plan: CEZ:AV0Z60930519 Keywords : bark damage * bark selection * bark chemical analysis * rowan * beech * spruce * mountain forest regeneration Subject RIV: GK - Forestry
Bright, B C; Hicke, J A; Hudak, A T
Bark beetle outbreaks kill billions of trees in western North America, and the resulting tree mortality can significantly impact local and regional carbon cycling. However, substantial variability in mortality occurs within outbreak areas. Our objective was to quantify landscape-scale effects of beetle infestations on aboveground carbon (AGC) stocks using field observations and remotely sensed data across a 5054 ha study area that had experienced a mountain pine beetle outbreak. Tree mortality was classified using multispectral imagery that separated green, red, and gray trees, and models relating field observations of AGC to LiDAR data were used to map AGC. We combined mortality and AGC maps to quantify AGC in beetle-killed trees. Thirty-nine per cent of the forested area was killed by beetles, with large spatial variability in mortality severity. For the entire study area, 40–50% of AGC was contained in beetle-killed trees. When considered on a per-hectare basis, 75–89% of the study area had >25% AGC in killed trees and 3–6% of the study area had >75% of the AGC in killed trees. Our results show that despite high variability in tree mortality within an outbreak area, bark beetle epidemics can have a large impact on AGC stocks at the landscape scale. (letter)
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.
Aaron S. Adams; Sandye M. Adams; Cameron R. Currie; Nancy E. Gillette; Kenneth F. Raffa
Bacterial communities are known to play important roles in insect life histories, yet their consistency or variation across populations is poorly understood. Bacteria associated with the bark beetle Dendroctonus valens LeConte from eight populations, ranging from Wisconsin to Oregon, were evaluated and compared. We used the culture-independent technique of denaturing...
Paul E. Tilden
Lindane is registered for remedial control of bark beetles; however, forestry uses are controversial and alternative chemicals are needed. Chlorpyrifos (Dursban 4E), carbaryl (Sevimol 4), and fenitrothion (Sumithion 8E) at 1, 2, and 4 pct active ingredient, and lindane at the registered dosage of 0.6 pct were sprayed on lodgepole pine (Pinus contorta...
B.L. Strom; R.A. Goyer; P.J. Shea
Olfactory deterrents have been proposed as tree protectants against attack by bark beetles, but their development has been hindered by a lack of knowledge of host selection behavior. Among the primary tree-killing (aggressive) Dendroctonus, vision appears to be an integral part of the host selection process. We evaluated the importance of vision in...
Douglas J. Rhodes; Jane Leslie Hayes; Chris Steiner
If retained, markers used in mark-release-recapture studies of bark beetle dispersal could provide valuable tools in the determination of post-dispersal fate. Retention of the internal marker rubidium (Rb) and of the external marker fluorescent powder during egg gallery construction, oviposition, and feeding were quantified at intervals from 0 to 96 hours by allowing...
Full Text Available In 1995 the corn rootworm (Diabrotica virgifera virgifera LeConte was detected for the first time in east Slavonia, Croatia. Its expansion to the west part has been very fast and from year to year populations of the pest are higher, especially when corn is planted after corn. The aim of this investigation was to find the best trap for monitoring Diabrotica. The studies were conducted by using three types of traps: the USA Trece lure trap, Multigard yellow sticky trap and Hungarian pheromone trap. The treatments were replicated four times in a maize field located in the east of Croatia, very near to the Yugoslavia border. The traps were placed in the field on the 23rd of June and the experiment continued until the 15th of September. Pheromone and Multigard sticky traps were replaced with new ones each month. Traps were positioned 60 m apart within a row and 70 m apart across maize rows. Silking occurred from 30 June to 8 August (exposed silk thoroughly brown and dry. This year was extremely dry, and the first beetles were noticed on the 15th of June. It was 20 days earlier than in 1999. Adult rootworm beetles were removed from the traps once weekly. Pheromone traps captured the most beetles (2263, Multigard sticky traps caught the second most (214 and lure traps the fewest (182 for the whole period. After the replacement of pheromone and Multigard traps, the capture of beetles increased. Of the total number of beetles caught, 85.10% was caught by the pheromone traps, 8.05% by the Multigard sticky traps and 6.85% by the lure traps. Due to this year’s dryness (50% less rainfall than the 20 year average, the investigation should be continued in the future to get more precise results.
McKenna, Duane D; Scully, Erin D; Pauchet, Yannick; Hoover, Kelli; Kirsch, Roy; Geib, Scott M; Mitchell, Robert F; Waterhouse, Robert M; Ahn, Seung-Joon; Arsala, Deanna; Benoit, Joshua B; Blackmon, Heath; Bledsoe, Tiffany; Bowsher, Julia H; Busch, André; Calla, Bernarda; Chao, Hsu; Childers, Anna K; Childers, Christopher; Clarke, Dave J; Cohen, Lorna; Demuth, Jeffery P; Dinh, Huyen; Doddapaneni, HarshaVardhan; Dolan, Amanda; Duan, Jian J; Dugan, Shannon; Friedrich, Markus; Glastad, Karl M; Goodisman, Michael A D; Haddad, Stephanie; Han, Yi; Hughes, Daniel S T; Ioannidis, Panagiotis; Johnston, J Spencer; Jones, Jeffery W; Kuhn, Leslie A; Lance, David R; Lee, Chien-Yueh; Lee, Sandra L; Lin, Han; Lynch, Jeremy A; Moczek, Armin P; Murali, Shwetha C; Muzny, Donna M; Nelson, David R; Palli, Subba R; Panfilio, Kristen A; Pers, Dan; Poelchau, Monica F; Quan, Honghu; Qu, Jiaxin; Ray, Ann M; Rinehart, Joseph P; Robertson, Hugh M; Roehrdanz, Richard; Rosendale, Andrew J; Shin, Seunggwan; Silva, Christian; Torson, Alex S; Jentzsch, Iris M Vargas; Werren, John H; Worley, Kim C; Yocum, George; Zdobnov, Evgeny M; Gibbs, Richard A; Richards, Stephen
Relatively little is known about the genomic basis and evolution of wood-feeding in beetles. We undertook genome sequencing and annotation, gene expression assays, studies of plant cell wall degrading enzymes, and other functional and comparative studies of the Asian longhorned beetle, Anoplophora glabripennis, a globally significant invasive species capable of inflicting severe feeding damage on many important tree species. Complementary studies of genes encoding enzymes involved in digestion of woody plant tissues or detoxification of plant allelochemicals were undertaken with the genomes of 14 additional insects, including the newly sequenced emerald ash borer and bull-headed dung beetle. The Asian longhorned beetle genome encodes a uniquely diverse arsenal of enzymes that can degrade the main polysaccharide networks in plant cell walls, detoxify plant allelochemicals, and otherwise facilitate feeding on woody plants. It has the metabolic plasticity needed to feed on diverse plant species, contributing to its highly invasive nature. Large expansions of chemosensory genes involved in the reception of pheromones and plant kairomones are consistent with the complexity of chemical cues it uses to find host plants and mates. Amplification and functional divergence of genes associated with specialized feeding on plants, including genes originally obtained via horizontal gene transfer from fungi and bacteria, contributed to the addition, expansion, and enhancement of the metabolic repertoire of the Asian longhorned beetle, certain other phytophagous beetles, and to a lesser degree, other phytophagous insects. Our results thus begin to establish a genomic basis for the evolutionary success of beetles on plants.
water. c) The phelloderm: Cells of the phelloderm layer are produced on the inner side of the phellogen .... brown or grey in colour. Table 1. continued . ... tracted from the dried Cinchona bark are used in the treatment of malarial fevers and are ...
May 2, 2008 ... The effect of the extract on the normal intestinal transit in mice was not significant. However, in the ... kunthianum stem bark was therefore investigated in mice and rats' in vivo ..... sons, London, 11: 544. Izzo AA, Nicoletti M, ...
Tinzaara, W; Gold, C S; Dicke, M; van Huis, A
As a response to attack by herbivores, plants can emit a variety of volatile substances that attract natural enemies of these insect pests. Predators of the banana weevil, Cosmopolites sordidus (Germar) (Coleoptera: Curculionidae) such as Dactylosternum abdominale (Coleoptera: Hydrophilidae) and Pheidole megacephala (Hymenoptera: Formicidae), are normally found in association with weevil-infested rotten pseudostems and harvested stumps. We investigated whether these predators are attracted to such environments in response to volatiles produced by the host plant, by the weevil, or by the weevil plant complex. We evaluated predator responses towards volatiles from banana pseudostem tissue (synomones) and the synthetic banana weevil aggregation pheromone Cosmolure+ in a two-choice olfactometer. The beetle D. abdominale was attracted to fermenting banana pseudostem tissue and Cosmolure+, whereas the ant P. megacephala was attracted only to fermented pseudostem tissue. Both predators were attracted to banana pseudostem tissue that had been damaged by weevil larvae irrespective of weevil presence. Adding pheromone did not enhance predator response to volatiles from pseudostem tissue fed on by weevils. The numbers of both predators recovered with pseudostem traps in the field from banana mats with a pheromone trap were similar to those in pseudostem traps at different distance ranges from the pheromone. Our study shows that the generalist predators D. abdominale and P. megacephala use volatiles from fermented banana pseudostem tissue as the major chemical cue when searching for prey.
Davídková, Markéta; Doležal, Petr
Roč. 405, DEC 01 (2017), s. 13-21 ISSN 0378-1127 Grant - others:Lesy ČR(CZ) 08/2009-2015 Institutional support: RVO:60077344 Keywords : re-emergence * sister broods * Ips typographus Subject RIV: EH - Ecology, Behaviour OBOR OECD: Zoology Impact factor: 3.064, year: 2016 http://www.sciencedirect.com/science/article/pii/S0378112717309507
Ally R. HARARI, Hadass STEINITZ
Full Text Available The role of female sex pheromones in natural selection, particularly as a means for species recognition to avoid the generation of hybrid offspring with low fitness, has been widely explored and is generally accepted by scholars. However, the significance of sex pheromones in shaping mate choice (sexual selection and in competition over breeding resources (social selection has been largely ignored. The effect of sexual selection on sex pheromones as a sexually dimorphic signaling trait has been discounted because the amount of pheromone released by females is typically minute, while the role of sex pheromones in competition over breeding resources (other than mates has not yet been considered. As a result of natural selection, variation in sex pheromones among females is expected to be low, and males are not expected to choose their mates among pheromone-releasing conspecific females. Sexual selection, on the other hand, should drive the increase in pheromone variance among females, and males are expected to choose females based on this variation. Moreover, social selection resulting from more general social interactions, for example competition among females for breeding sites and food, should also promote variance among female sex pheromones. Here, we review the current evidence for each of the three selection processes acting on sex pheromones of female moths as an advertising trait. We suggest that the three selection types are not mutually exclusive but rather act together to promote different fitness components in diverse ecological situations [Current Zoology 59 (4: 569–578, 2013].
Costa-Leonardo, Ana Maria; Haifig, Ives
Termites are eusocial insects that have a peculiar and intriguing system of communication using pheromones. The termite pheromones are composed of a blend of chemical substances and they coordinate different social interactions or activities, including foraging, building, mating, defense, and nestmate recognition. Some of these sociochemicals are volatile, spreading in the air, and others are contact pheromones, which are transmitted by trophallaxis and grooming. Among the termite semiochemicals, the most known are alarm, trail, sex pheromones, and hydrocarbons responsible for the recognition of nestmates. The sources of the pheromones are exocrine glands located all over the termite body. The principal exocrine structures considered pheromone-producing glands in Isoptera are the frontal, mandibular, salivary or labial, sternal, and tergal glands. The frontal gland is the source of alarm pheromone and defensive chemicals, but the mandibular secretions have been little studied and their function is not well established in Isoptera. The secretion of salivary glands involves numerous chemical compounds, some of them without pheromonal function. The worker saliva contains a phagostimulating pheromone and probably a building pheromone, while the salivary reservoir of some soldiers contains defensive chemicals. The sternal gland is the only source of trail-following pheromone, whereas sex pheromones are secreted by two glandular sources, the sternal and tergal glands. To date, the termite semiochemicals have indicated that few molecules are involved in their chemical communication, that is, the same compound may be secreted by different glands, different castes and species, and for different functions, depending on the concentration. In addition to the pheromonal parsimony, recent studies also indicate the occurrence of a synergic effect among the compounds involved in the chemical communication of Isoptera. Copyright © 2010 Elsevier Inc. All rights reserved.
The importance of chemical cues in insect behaviour is well established (Bell & Cardé, 1984). The best known examples include the sex pheromones of butterflies and moths, and the aggregation pheromones of bark beetles. In eusocial insects (bees, wasps, ants, and termites) pheromones are
Stephens, K; Hegeman, G D; White, D
An extracellular, diffusible signaling molecule (pheromone) was produced by Stigmatella aurantiaca during fruiting body formation. The pheromone decreased the aggregation period in both the light and the dark and substituted for light in stimulating the maturation of aggregates into fruiting bodies. The cells were more sensitive to lower concentrations of pheromone in the light than in the dark, possibly explaining the stimulation of aggregation and fruiting body formation by light. The phero...
The analgesic activity of the water extracts (50,100 and150 mg/Kg body weight) of the root bark, stem bark, leaves, fruits and seeds of Carissa edulis were evaluated in mice using the mechanical method (tail-chip method) and chemical method (acetic acid induced writhing). The plant was found to have analgesic activity, ...
Mujica-Parodi, Lilianne R; Strey, Helmut
.... Task I, Optimization of Sample Collection, focused on the collection of the putative alarm pheromone via axillary sweat samples obtained during reference (physical exercise) and arousal (skydive) conditions...
[9, 10- 3 H 2 ]Z9-14:Ac was synthesized at high specific activity ( 3 H, 58 Ci/mmole) by partial tritiation of the corresponding alkyne and was converted to the labeled Z9-14:OH and Z9-14:Al to study tissue specificity of acetate esterase (E), alcohol oxidase (OX), and aldehyde dehydrogenase (ALDH) in male and female Heliothis virescens. Soluble and membrane-associated enzyme activities were determined by radio-TLC assays. Compounds of the tritium-labeled Z11-16 series were synthesized and their in vitro fates examined as well. In order to achieve an alternative approach in which (1) pheromone receptor proteins would be stoichiometrically and irreversibly modified, or (2) pheromone-catabolizing enzymes are inactivated by tight-binding or irreversible inhibitors, we have designed analogues of pheromones of lepidopterous insect pests and assayed their biological activity in vitro and in vivo. Various fluorinated molecules such as acyl fluorides, fluoroolefins, 2-fluoro aldehydes, 2,2-difluoro aldehydes and trifluoromethyl ketones were synthesized. The synthesis of some other functional groups such as cyclopropanones, cyclopropanols, cyclopropyl carbinols, cyclopropyl aldehydes and Michael acceptors will also be discussed
Daniel R. Miller; John H. Borden
We conducted seven experiments in stands of mature lodgepole pine in southern British Columbia to elucidate the role of host volatiles in the semiochemical ecology of the pine engraver, Ips pini (Say) (Coleoptera: Scolytidae), with particular reference to the behavioral responses of predators and competing species of bark beetles. Our results demonstrated that the...
Brice A. McPherson; David L. Wood; David M. Rizzo; Pavel Svihra; Steve Tjosvold; Andrew J. Storer; Richard B. Standiford
As the name implies, sudden oak death, caused by Phytophthora ramorum, kills many, if not most of the coast live oaks, Quercus agrifolia, that become infected (McPherson and others, 2005). Several genera of ambrosia and bark beetles (Coleoptera: Scolytidae) colonize bleeding (infected) trees and are suspected to hasten tree death....
Mayrhofer, Severine; Weber, Jan M; Pöggeler, Stefanie
The homothallic, filamentous ascomycete Sordaria macrospora is self-fertile and produces sexual fruiting bodies (perithecia) without a mating partner. Even so, S. macrospora transcriptionally expresses two pheromone-precursor genes (ppg1 and ppg2) and two pheromone-receptor genes (pre1 and pre2). The proteins encoded by these genes are similar to alpha-factor-like and a-factor-like pheromones and to G-protein-coupled pheromone receptors of the yeast Saccharomyces cerevisiae. It has been suggested that in S. macrospora, PPG1/PRE2 and PPG2/PRE1 form two cognate pheromone-receptor pairs. To investigate their function, we deleted (delta) pheromone-precursor genes (delta ppg1, delta ppg2) and receptor genes (delta pre1, delta pre2) and generated single- as well as double-knockout strains. No effect on vegetative growth, fruiting-body, and ascospore development was seen in the single pheromone-mutant and receptor-mutant strains, respectively. However, double-knockout strains lacking any compatible pheromone-receptor pair (delta pre2/delta ppg2, delta pre1/delta ppg1) and the double-pheromone mutant (delta ppg1/delta ppg2) displayed a drastically reduced number of perithecia and sexual spores, whereas deletion of both receptor genes (delta pre1/delta pre2) completely eliminated fruiting-body and ascospore formation. The results suggest that pheromones and pheromone receptors are required for optimal sexual reproduction of the homothallic S. macrospora.
Suckling, D.M.; Peck, R.W.; Manning, L.M.; Stringer, L.D.; Cappadonna, J.; El-Sayed, A. M.
Disruption of Argentine ant trail following and reduced ability to forage (measured by bait location success) was achieved after presentation of an oversupply of trail pheromone, (Z)-9-hexadecenal. Experiments tested single pheromone point sources and dispersion of a formulation in small field plots. Ant walking behavior was recorded and digitized by using video tracking, before and after presentation of trail pheromone. Ants showed changes in three parameters within seconds of treatment: (1) Ants on trails normally showed a unimodal frequency distribution of walking track angles, but this pattern disappeared after presentation of the trail pheromone; (2) ants showed initial high trail integrity on a range of untreated substrates from painted walls to wooden or concrete floors, but this was significantly reduced following presentation of a point source of pheromone; (3) the number of ants in the pheromone-treated area increased over time, as recruitment apparently exceeded departures. To test trail disruption in small outdoor plots, the trail pheromone was formulated with carnuba wax-coated quartz laboratory sand (1 g quartz sand/0.2 g wax/1 mg pheromone). The pheromone formulation, with a half-life of 30 h, was applied by rotary spreader at four rates (0, 2.5, 7.5, and 25 mg pheromone/m2) to 1- and 4-m2 plots in Volcanoes National Park, Hawaii. Ant counts at bait cards in treated plots were significantly reduced compared to controls on the day of treatment, and there was a significant reduction in ant foraging for 2 days. These results show that trail pheromone disruption of Argentine ants is possible, but a much more durable formulation is needed before nest-level impacts can be expected. ?? 2008 Springer Science+Business Media, LLC.
Roth, Marla; Hussain, Altaf; Cale, Jonathan A; Erbilgin, Nadir
Lodgepole pine (Pinus contorta) forests have experienced severe mortality from mountain pine beetle (MPB) (Dendroctonus ponderosae Hopkins) in western North America for the last several years. Although the mechanisms by which beetles kill host trees are unclear, they are likely linked to pine defense monoterpenes that are synthesized from carbohydrate reserves. However, how carbohydrates and monoterpenes interact in response to MPB colonization is unknown. Understanding this relationship could help to elucidate how pines succumb to bark beetle attack. We compared concentrations of individual and total monoterpenes and carbohydrates in the phloem of healthy pine trees with those naturally colonized by MPB. Trees attacked by MPB had nearly 300% more monoterpenes and 40% less carbohydrates. Total monoterpene concentrations were most strongly associated with the concentration of sugars in the phloem. These results suggest that bark beetle colonization likely depletes carbohydrate reserves by increasing the production of carbon-rich monoterpenes, and other carbon-based secondary compounds. Bark beetle attacks also reduce water transport causing the disruption of carbon transport between tree foliage and roots, which restricts carbon assimilation. Reduction in carbohydrate reserves likely contributes to tree mortality.
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 to...
Wiley, Erin; Rogers, Bruce J; Hodgkinson, Robert; Landhäusser, Simon M
Bark beetle outbreaks are an important cause of tree death, but the process by which trees die remains poorly understood. The effect of beetle attack on whole-tree nonstructural carbohydrate (NSC) dynamics is particularly unclear, despite the potential role of carbohydrates in plant defense and survival. We monitored NSC dynamics of all organs in attacked and protected lodgepole pines (Pinus contorta) during a mountain pine beetle (Dendroctonus ponderosae) outbreak in British Columbia, starting before beetle flight in June 2011 through October 2012, when most attacked trees had died. Following attack, NSC concentrations were first reduced in the attacked region of the bole. The first NSC reduction in a distant organ appeared in the needles at the end of 2011, while branch and root NSC did not decline until much later in 2012. Attacked trees that were still alive in October 2012 had less beetle damage, which was negatively correlated with initial bark sugar concentrations in the attack region. The NSC dynamics of dying trees indicate that trees were killed by a loss of water conduction and not girdling. Further, our results identify locally reduced carbohydrate availability as an important mechanism by which stressors like drought may increase tree susceptibility to biotic attack. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.
Diana L. Six
Full Text Available While the use of timber harvests is generally accepted as an effective approach to controlling bark beetles during outbreaks, in reality there has been a dearth of monitoring to assess outcomes, and failures are often not reported. Additionally, few studies have focused on how these treatments affect forest structure and function over the long term, or our forests’ ability to adapt to climate change. Despite this, there is a widespread belief in the policy arena that timber harvesting is an effective and necessary tool to address beetle infestations. That belief has led to numerous proposals for, and enactment of, significant changes in federal environmental laws to encourage more timber harvests for beetle control. In this review, we use mountain pine beetle as an exemplar to critically evaluate the state of science behind the use of timber harvest treatments for bark beetle suppression during outbreaks. It is our hope that this review will stimulate research to fill important gaps and to help guide the development of policy and management firmly based in science, and thus, more likely to aid in forest conservation, reduce financial waste, and bolster public trust in public agency decision-making and practice.
Leite, Carla; Pereira, Helena
Tree barks are among the less studied forest products notwithstanding their relevant physiological and protective role in tree functioning. The large diversity in structure and chemical composition of barks makes them a particularly interesting potential source of chemicals and bio-products, at present valued in the context of biorefineries. One of the valuable components of barks is cork (phellem in anatomy) due to a rather unique set of properties and composition. Cork from the cork oak (Quercus suber) has been extensively studied, mostly because of its economic importance and worldwide utilization of cork products. However, several other species have barks with substantial cork amounts that may constitute additional resources for cork-based bioproducts. This paper makes a review of the tree species that have barks with significant proportion of cork and on the available information regarding their bark structural and chemical characterization. A general integrative appraisal of the formation and types of barks and of cork development is also given. The knowledge gaps and the potential interesting research lines are identified and discussed, as well as the utilization perspectives.
Powell, Erinn N; Raffa, Kenneth F
We examined the effect of wildfire injury on lodgepole pine chemical defenses against mountain pine beetle. We compared the constitutive phloem chemistry among uninjured, lightly-, moderately-, and severely-injured trees, and the induced chemistry elicited by simulated beetle attack, among these same categories. We also compared the entry rates of caged female beetles into trees of these categories. The volatiles we studied included thirteen monoterpene hydrocarbons, four allylic monoterpene alcohols, one ester, and one phenyl propanoid, of which the monoterpene hydrocarbons always comprised 96% or more of the total. Fire injury reduced the total concentration of these compounds in the induced but not constitutive phloem tissue of lodgepole pines. Fire injury also affected the relative composition of some volatiles in both induced and constitutive phloem. For example, increased fire injury reduced 4-allylanisole, a host compound that inhibits mountain pine beetle aggregation. Increased fire injury also increased (-) α-pinene, which can serve as precursor of pheromone communication. However, it also reduced myrcene and terpinolene, which can serve as stimulants and synergists of pheromone communication. Beetle entry did not show statistical differences among fire injury categories, although there was a trend to increased entry with fire injury. These results suggest that the reduced ability of trees to mobilize induced chemical defenses is an important mechanism behind the higher incidence of attack on fire-injured trees in the field. Future studies should concentrate on whether beetles that enter fire-injured trees are more likely to elicit aggregation, based on the differences we observed in volatile composition.
Hulcr, J.; Kolařík, Miroslav; Kirkendall, L.
Roč. 43, - (2007), s. 151-159 ISSN 0334-5114 Grant - others:GA ČR(CZ) GD206/03/H034 Program:GD Institutional research plan: CEZ:AV0Z50200510 Source of funding: V - iné verejné zdroje Keywords : scolytodes unipunctatus * cecropia * raffaela Subject RIV: EE - Microbiology, Virology Impact factor: 0.598, year: 2007
Sun, Mengjing; Liu, Yang; Walker, William B.; Liu, Chengcheng; Lin, Kejian; Gu, Shaohua; Zhang, Yongjun; Zhou, Jingjiang; Wang, Guirong
Moths depend on olfactory cues such as sex pheromones to find and recognize mating partners. Pheromone receptors (PRs) and Pheromone binding proteins (PBPs) are thought to be associated with olfactory signal transduction of pheromonal compounds in peripheral olfactory reception. Here six candidate pheromone receptor genes in the diamondback moth, Plutella xyllostella were identified and cloned. All of the six candidate PR genes display male-biased expression, which is a typical characteristic...
Damberger, Fred F.; Michel, Erich; Ishida, Yuko; Leal, Walter S.; Wüthrich, Kurt
Pheromone recognition by insect olfactory organs is critical for the ability of insects to locate mates. The silkworm moth Bombyx mori has long served as a model organism for studies of this process. Key components in the sensory organs have been identified, including the pheromone bombykol, pheromone-binding protein (BmorPBP), ligand-degrading enzymes, and the pheromone receptor, but many details of the mechanism allowing highly sensitive and selective pheromone detection are still elusive. ...
Dec 1, 2009 ... 2Institute of Biochemistry and Biotechnology, University of the Punjab, Lahore, Pakistan. 3Department of ... most important energy source around the globe ... T. castaneum (red flour beetle) samples were collected from rice.
Ramle, M; Wahid, M B; Norman, K; Glare, T R; Jackson, T A
The rhinoceros beetle, Oryctes rhinoceros, has emerged as a serious pest of oil palm since the prohibition of burning as a method for maintaining estate hygiene in the 1990s. The abundance of beetles is surprising given that the Malay peninsula was the site of first discovery of the Oryctes virus, which has been used to effect good as a biological control agent in other regions. A survey of adult beetles was carried out throughout Malaysia using pheromone traps. Captured beetles were examined for presence of virus using both visual/microscopic examination and PCR detection methods. The survey indicated that Oryctes virus was common in Malaysia among the adult beetles. Viral DNA analysis was carried out after restriction with HindIII enzyme and indicated at least three distinct viral genotypes. Bioassays were used to compare the viral strains and demonstrate that one strain (type B) is the most virulent against both larvae and adults of the beetle. Virus type B has been cultured and released into healthy populations where another strain (type A) forms the natural background. Capture and examination of beetles from the release site and surrounding area has shown that the spread and persistence of the applied virus strain is accompanied by a reduction in palm frond damage.
of ant pheromones may be sufficient to repel pest insects from ant territories. The study of ant semiochemicals is in its infancy, yet, evidence for their potential use in pest management is starting to build up. Pheromones from four of five tested ant species have been shown to deter herbivorous insect...... prey and competing ant species are also deterred by ant deposits, whereas ant symbionts may be attracted to them. Based on these promising initial findings, it seems advisable to further elucidate the signaling properties of ant pheromones and to test and develop their use in future pest management....
Houck, Lynne D
This selective review considers herpetological papers that feature the use of chemical cues, particularly pheromones involved in reproductive interactions between potential mates. Primary examples include garter snake females that attract males, lacertid lizards and the effects of their femoral gland secretions, aquatic male newts that chemically attract females, and terrestrial salamander males that chemically persuade a female to mate. Each case study spans a number of research approaches (molecular, biochemical, behavioral) and is related to sensory processing and the physiological effects of pheromone delivery. These and related studies show that natural pheromones can be identified, validated with behavioral tests, and incorporated in research on vomeronasal functional response.
Sha Chu, Sha; Fang Wang, Cheng; Shan Du, Shu; Liang Liu, Shao; Long Liu, Zhi
During our screening program for new agrochemicals from Chinese medicinal herbs, the essential oil of Illicium difengpi stem bark was found to possess strong insecticidal activities against the maize weevil, Sitophilus zeamais (Motschulsky) (Coleoptera: Curculionidae) and red flour beetle, Tribolium castaneum Herbst (Coleoptera: Tenebrionidae). A total of 37 components of the essential oil of I. difengpi were identified. The main components of the essential oil were safrole (23.61%), linalool...
Two studies of the effects of perfume additives, termed human pheromones by the authors, have conveyed the message that these substances can promote an increase in human sociosexual behaviour [Physiol. Behav. 75 (2003) R1; Arch. Sex. Behav. 27 (1998) R2]. The present paper presents an extended analysis of this data. It is shown that in neither study is there a statistically significant increase in any of the sociosexual behaviours for the experimental groups. In the control groups of both studies, there are, however, moderate but statistically significant decreases in the corresponding behaviour. Most notably, there is no support in data for the claim that the substances increase the attractiveness of the wearers of the substances to the other sex. It is concluded that more research using matched homogenous groups of participants is needed. Copyright 2004 Elsevier Inc.
Hu, Mao-Bin; Henry, Y. K. Lau; Ling, Xiang; Jiang, Rui
We adopt the concept of using pheromones to generate a set of static paths that can reach the performance of global dynamic routing strategy [Phys. Rev. E 81 (2010) 016113]. The path generation method consists of two stages. In the first stage, a pheromone is dropped to the nodes by packets forwarded according to the global dynamic routing strategy. In the second stage, pheromone static paths are generated according to the pheromone density. The output paths can greatly improve traffic systems' overall capacity on different network structures, including scale-free networks, small-world networks and random graphs. Because the paths are static, the system needs much less computational resources than the global dynamic routing strategy.
Female sex pheromone production in certain moth species have been shown to be regulated by a cephalic endo- crine peptidic .... A nitrogen laser (659 nm) was used as the desorption/ .... from the Council of Scientific and Industrial Research.
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.
De Fine Licht Henrik H
Full Text Available Abstract Introduction In wood-dwelling fungus-farming weevils, the so-called ambrosia beetles (Curculionidae: Scolytinae and Platypodinae, wood in the excavated tunnels is used as a medium for cultivating fungi by the combined action of digging larvae (which create more space for the fungi to grow and of adults sowing and pruning the fungus. The beetles are obligately dependent on the fungus that provides essential vitamins, amino acids and sterols. However, to what extent microbial enzymes support fungus farming in ambrosia beetles is unknown. Here we measure (i 13 plant cell-wall degrading enzymes in the fungus garden microbial consortium of the ambrosia beetle Xyleborinus saxesenii, including its primary fungal symbionts, in three compartments of laboratory maintained nests, at different time points after gallery foundation and (ii four specific enzymes that may be either insect or microbially derived in X. saxesenii adult and larval individuals. Results We discovered that the activity of cellulases in ambrosia fungus gardens is relatively small compared to the activities of other cellulolytic enzymes. Enzyme activity in all compartments of the garden was mainly directed towards hemicellulose carbohydrates such as xylan, glucomannan and callose. Hemicellulolytic enzyme activity within the brood chamber increased with gallery age, whereas irrespective of the age of the gallery, the highest overall enzyme activity were detected in the gallery dump material expelled by the beetles. Interestingly endo-β-1,3(4-glucanase activity capable of callose degradation was identified in whole-body extracts of both larvae and adult X. saxesenii, whereas endo-β-1,4-xylanase activity was exclusively detected in larvae. Conclusion Similar to closely related fungi associated with bark beetles in phloem, the microbial symbionts of ambrosia beetles hardly degrade cellulose. Instead, their enzyme activity is directed mainly towards comparatively more easily
De Fine Licht, Henrik H; Biedermann, Peter H W
In wood-dwelling fungus-farming weevils, the so-called ambrosia beetles (Curculionidae: Scolytinae and Platypodinae), wood in the excavated tunnels is used as a medium for cultivating fungi by the combined action of digging larvae (which create more space for the fungi to grow) and of adults sowing and pruning the fungus. The beetles are obligately dependent on the fungus that provides essential vitamins, amino acids and sterols. However, to what extent microbial enzymes support fungus farming in ambrosia beetles is unknown. Here we measure (i) 13 plant cell-wall degrading enzymes in the fungus garden microbial consortium of the ambrosia beetle Xyleborinus saxesenii, including its primary fungal symbionts, in three compartments of laboratory maintained nests, at different time points after gallery foundation and (ii) four specific enzymes that may be either insect or microbially derived in X. saxesenii adult and larval individuals. We discovered that the activity of cellulases in ambrosia fungus gardens is relatively small compared to the activities of other cellulolytic enzymes. Enzyme activity in all compartments of the garden was mainly directed towards hemicellulose carbohydrates such as xylan, glucomannan and callose. Hemicellulolytic enzyme activity within the brood chamber increased with gallery age, whereas irrespective of the age of the gallery, the highest overall enzyme activity were detected in the gallery dump material expelled by the beetles. Interestingly endo-β-1,3(4)-glucanase activity capable of callose degradation was identified in whole-body extracts of both larvae and adult X. saxesenii, whereas endo-β-1,4-xylanase activity was exclusively detected in larvae. Similar to closely related fungi associated with bark beetles in phloem, the microbial symbionts of ambrosia beetles hardly degrade cellulose. Instead, their enzyme activity is directed mainly towards comparatively more easily accessible hemicellulose components of the ray
Full Text Available The insect's olfactory system is so selective that male moths, for example, can discriminate female-produced sex pheromones from compounds with minimal structural modifications. Yet, there is an exception for this "lock-and-key" tight selectivity. Formate analogs can be used as replacement for less chemically stable, long-chain aldehyde pheromones, because male moths respond physiologically and behaviorally to these parapheromones. However, it remained hitherto unknown how formate analogs interact with aldehyde-sensitive odorant receptors (ORs. Neuronal responses to semiochemicals were investigated with single sensillum recordings. Odorant receptors (ORs were cloned using degenerate primers, and tested with the Xenopus oocyte expression system. Quality, relative quantity, and purity of samples were evaluated by gas chromatography and gas chromatography-mass spectrometry. We identified olfactory receptor neurons (ORNs housed in trichoid sensilla on the antennae of male navel orangeworm that responded equally to the main constituent of the sex pheromone, (11Z,13Z-hexadecadienal (Z11Z13-16Ald, and its formate analog, (9Z,11Z-tetradecen-1-yl formate (Z9Z11-14OFor. We cloned an odorant receptor co-receptor (Orco and aldehyde-sensitive ORs from the navel orangeworm, one of which (AtraOR1 was expressed specifically in male antennae. AtraOR1•AtraOrco-expressing oocytes responded mainly to Z11Z13-16Ald, with moderate sensitivity to another component of the sex pheromone, (11Z,13Z-hexadecadien-1-ol. Surprisingly, this receptor was more sensitive to the related formate than to the natural sex pheromone. A pheromone receptor from Heliothis virescens, HR13 ( = HvirOR13 showed a similar profile, with stronger responses elicited by a formate analog than to the natural sex pheromone, (11Z-hexadecenal thus suggesting this might be a common feature of moth pheromone receptors.
Geiselhardt, Sven; Otte, Tobias; Hilker, Monika
The role of phenotypical plasticity in ecological speciation and the evolution of sexual isolation remains largely unknown. We investigated whether or not divergent host plant use in an herbivorous insect causes assortative mating by phenotypically altering traits involved in mate recognition. We found that males of the mustard leaf beetle Phaedon cochleariae preferred to mate with females that were reared on the same plant species to females provided with a different plant species, based on divergent cuticular hydrocarbon profiles that serve as contact pheromones. The cuticular hydrocarbon phenotypes of the beetles were host plant specific and changed within 2 weeks after a shift to a novel host plant species. We suggest that plant-induced phenotypic divergence in mate recognition cues may act as an early barrier to gene flow between herbivorous insect populations on alternative host species, preceding genetic divergence and thus, promoting ecological speciation. © 2012 Blackwell Publishing Ltd/CNRS.
Single and combination insecticides evaluated as regulatory immersion treatments to eliminate third-instar Japanese beetle (Coleoptera: Scarabaeidae) from small diameter field-grown and containerized nursery plants
Japanese beetles, Popillia japonica Newman, are a nursery regulatory pest. Immersion of field-grown plants harvested as balled and burlapped (B&B) or container plants grown in pine bark substrates in a solution of chlorpyrifos or bifenthrin is allowed for certification in the Domestic Japanese Beet...
Sillam-Dusses, David; Hanus, Robert; Abd El-Latif, A. O.; Jiroš, Pavel; Krasulová, Jana; Kalinová, Blanka; Valterová, Irena; Šobotník, Jan
Roč. 37, č. 2 (2011), s. 179-188 ISSN 0098-0331 R&D Projects: GA ČR GAP506/10/1570 Institutional research plan: CEZ:AV0Z40550506 Keywords : sex pheromone * trail pheromone * Psammotermes hybostoma * termites * Rhinotermitidae Subject RIV: CC - Organic Chemistry Impact factor: 2.657, year: 2011
Galdino, Tarcísio Visintin da Silva; Ferreira, Dalton de Oliveira; Santana Júnior, Paulo Antônio; Arcanjo, Lucas de Paulo; Queiroz, Elenir Aparecida; Sarmento, Renato Almeida; Picanço, Marcelo Coutinho
The knowledge of the spatiotemporal dynamics of pathogens and their vectors is an important step in determining the pathogen dispersion pattern and the role of vectors in disease dynamics. However, in the case of mango wilt little is known about its spatiotemporal dynamics and the relationship of its vector [the beetle Hypocryphalus mangiferae (Stebbing 1914)] to these dynamics. The aim of this work was to determine the spatial-seasonal dynamic of H. mangiferae attacks and mango wilt in mango orchards and to verify the importance of H. mangiferae in the spatiotemporal dynamics of the disease. Two mango orchards were monitored during a period of 3 yr. The plants in these orchards were georeferenced and inspected monthly to quantify the number of plants attacked by beetles and the fungus. In these orchards, the percentage of mango trees attacked by beetles was always higher than the percentage infected by the fungus. The colonization of mango trees by beetles and the fungus occurred by colonization of trees both distant and proximal to previously attacked trees. The new plants attacked by the fungus emerged in places where the beetles had previously begun their attack. This phenomenon led to a large overlap in sites of beetle and fungal occurrence, indicating that establishment by the beetle was followed by establishment by the fungus. This information can be used by farmers to predict disease infection, and to control bark beetle infestation in mango orchards. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: email@example.com.
Nielsen, O; Davey, William John; Nielsen, Olaf
Conjugation between two haploid yeast cells is generally controlled by the reciprocal action of diffusible mating pheromones, cells of each mating type releasing pheromones that induce mating-specific changes in cells of the opposite type. Recent studies into pheromone signalling in the fission...
Milberg, Per; Bergman, Karl-Olof; Sancak, Kerem; Jansson, Nicklas
Old living oaks (Quercus robur) are known as a very species-rich habitat for saproxylic beetles, but it is less clear to what extent such veteran trees differ from an even rarer feature: downed trunks of large oaks. In this study, we set out to sample this habitat, using window traps, with two aims: (1) to describe the variation of assemblages among downed trunks of different type and (2) to compare beetles on downed oaks with data from veteran standing trees. The results showed that trunk volume and sun exposure better explained assemblages as well as species numbers on downed trunks than did decay stage. Furthermore, species classified as facultative saproxylic species showed weak or no differentiation among downed trunks. Species with different feeding habits showed no apparent differentiation among downed trunks. Furthermore, species composition on dead, downed oak trunks differed sharply from that of living, veteran oaks. Wood or bark feeders were more common on veterans than downed trunks, but there was no difference for those species feeding on fungi or those feeding on insects and their remains. In conclusion, for a successful conservation of the saproxylic beetle fauna it is important to keep downed oak trunks, and particularly large ones, in forest and pastures as they constitute a saproxylic habitat that differs from that of living trees.
Cook, Laura C.; Federle, Michael J.
Intercellular chemical signaling in bacteria, commonly referred to as quorum sensing (QS), relies on the production and detection of compounds known as pheromones to elicit coordinated responses among members of a community. Pheromones produced by Gram-positive bacteria are comprised of small peptides. Based on both peptide structure and sensory system architectures, Gram-positive bacterial signaling pathways may be classified into one of four groups with a defining hallmark: cyclical peptides of the Agr type, peptides that contain Gly-Gly processing motifs, sensory systems of the RNPP family, or the recently characterized Rgg-like regulatory family. The recent discovery that Rgg family members respond to peptide pheromones increases substantially the number of species in which QS is likely a key regulatory component. These pathways control a variety of fundamental behaviors including conjugation, natural competence for transformation, biofilm development, and virulence factor regulation. Overlapping QS pathways found in multiple species and pathways that utilize conserved peptide pheromones provide opportunities for interspecies communication. Here we review pheromone signaling identified in the genera Enterococcus and Streptococcus, providing examples of all four types of pathways. PMID:24118108
Chen, Da-Song; Dai, Jian-Qing; Han, Shi-Chou
The diamondback moth was estimated to increase costs to the global agricultural economy as the global area increase of Brassica vegetable crops and oilseed rape. Sex pheromones traps are outstanding tools available in Integrated Pest Management for many years and provides an effective approach for DBM population monitoring and control. The ratio of two major sex pheromone compounds shows geographical variations. However, the limitation of our information in the DBM pheromone biosynthesis dampens our understanding of the ratio diversity of pheromone compounds. Here, we constructed a transcriptomic library from the DBM pheromone gland and identified genes putatively involved in the fatty acid biosynthesis, pheromones functional group transfer, and β-oxidation enzymes. In addition, odorant binding protein, chemosensory protein and pheromone binding protein genes encoded in the pheromone gland transcriptome, suggest that female DBM moths may receive odors or pheromone compounds via their pheromone gland and ovipositor system. Tissue expression profiles further revealed that two ALR, three DES and one FAR5 genes were pheromone gland tissue biased, while some chemoreception genes expressed extensively in PG, pupa, antenna and legs tissues. Finally, the candidate genes from large-scale transcriptome information may be useful for characterizing a presumed biosynthetic pathway of the DBM sex pheromone.
Spiegel, Carolina N; Batista-Pereira, Luciane G; Bretas, Jorge A C; Eiras, Alvaro E; Hooper, Antony M; Peixoto, Alexandre A; Soares, Maurilio J
The sand fly Lutzomyia longipalpis (Lutz & Neiva) (Diptera: Psychodidae: Phlebotominae) is the main vector of American visceral leishmaniasis. Adult males produce a terpenoid sex pheromone that in some cases also acts as male aggregation pheromone. We have analyzed the correlation between male pheromone production levels and pheromone gland cell morphogenesis after adult emergence from pupae. The abdominal tergites of L. longipalpis males were dissected and fixed in glutaraldehyde for transmission electron microscopy, or the pheromone was extracted in analytical grade hexane. Pheromone chemical analysis was carried out at 3- to 6-h intervals during the first 24 h after emergence and continued daily until the seventh day. All extracts were analyzed by gas chromatography. For the morphological analysis, we used insects collected at 0-6, 9-12, 12-14, and 96 h after emergence. Ultrastructural data from 0- to 6-h-old adult males revealed smaller pheromone gland cells with small microvilli at the end apparatus. Lipid droplets and peroxisomes were absent or very rare, but a large number of mitochondria could be seen. Lipid droplets started to appear in the gland cells cytoplasm approximately 9 h after adult emergence, and their number and size increased with age, together with the presence of several peroxisomes, suggesting a role for these organelles in pheromone biosynthesis. At 12-15 h after emergence, the lipid droplets were mainly distributed near the microvilli but were smaller than those in mature older males (4 d old). Pheromone biosynthesis started around 12 h after emergence and increased continuously during the first 3 d, stabilizing thereafter, coinciding with the period when males are more able to attract females.
Ding, Bao-Jian; Löfstedt, Christer
Moths rely heavily on pheromone communication for mate finding. The pheromone components of most moths are modified from the products of normal fatty acid metabolism by a set of tissue-specific enzymes. The turnip moth, Agrotis segetum uses a series of homologous fatty-alcohol acetate esters ((Z)-5-decenyl, (Z)-7-dodecenyl, and (Z)-9 tetradecenyl acetate) as its sex pheromone components. The ratio of the components differs between populations, making this species an interesting subject for studies of the enzymes involved in the biosynthetic pathway and their influence on sex pheromone variation. Illumina sequencing and comparative analysis of the transcriptomes of the pheromone gland and abdominal epidermal tissue, enabled us to identify genes coding for putative key enzymes involved in the pheromone biosynthetic pathway, such as fatty acid synthase, β-oxidation enzymes, fatty-acyl desaturases (FAD), fatty-acyl reductases (FAR), and acetyltransferases. We functionally assayed the previously identified ∆11-desaturase [GenBank: ES583599, JX679209] and FAR [GenBank: JX679210] and candidate acetyltransferases (34 genes) by heterologous expression in yeast. The functional assay confirmed that the ∆11-desaturase interacts with palmitate and produces (Z)-11-hexadecenoate, which is the common unsaturated precursor of three homologous pheromone component acetates produced by subsequent chain-shortening, reduction and acetylation. Much lower, but still visible, activity on 14C and 12C saturated acids may account for minor pheromone compounds previously observed in the pheromone gland. The FAR characterized can operate on various unsaturated fatty acids that are the immediate acyl precursors of the different A. segetum pheromone components. None of the putative acetyltransferases that we expressed heterologously did acetylate any of the fatty alcohols tested as substrates. The massive sequencing technology generates enormous amounts of candidate genes potentially
Ants control pests via predation and physical deterrence; however, ant communication is based on chemical cues which may serve as warning signals to potential prey and other intruders. The presence of ant pheromones may, thus, be sufficient to repel pests from ant territories. This mini-review sh......-review shows that four out of five tested ant species deposit pheromones that repel herbivorous prey from their host plants.......Ants control pests via predation and physical deterrence; however, ant communication is based on chemical cues which may serve as warning signals to potential prey and other intruders. The presence of ant pheromones may, thus, be sufficient to repel pests from ant territories. This mini...
Papaloucas, Marios; Kyriazi, Kyriaki; Kouloulias, Vassilis
Nowadays, antidoping laboratories are improving detection methods to confirm the use of forbidden substances. These tests are based both on direct identification of new substances or their metabolites and on indirect evaluation of changes in gene, protein, or metabolite patterns (genomics, proteomics, or metabolomics). The World Anti-Doping Agency (WADA) officially monitors anabolic steroids, hormones, growth factors, β-agonists, hormone and metabolic modulators, masking agents, street drugs, manipulation of blood and blood components, chemical and physical manipulation, gene doping, stimulants, narcotics, glucocorticosteroids, and β-blockers. However, several other substances are under review by WADA. Pheromones accomplish the structure and function of life from its first step, while they have an impact on the body's performance. Both testosterone and pheromones have an ergogenic effect that could potentially affect an athlete's performance. The authors share their questions concerning the potential impact of pheromones in sports.
Full Text Available Social olfactory signals, often known as pheromones, are powerful regulators of reproductive function. These chemosignals can be detected by two olfactory systems, namely the main or the accessory olfactory systems. While initially anatomically segregated, both systems converge functionally as they can detect and process overlapping sets of chemosignals. This convergence also takes place at the level of their central projections in the hypothalamus. It is probably at this level that future investigations will be needed. Indeed, if the physiology of both olfactory system and reproductive function are now quite well characterized, the interrelation between both systems is unclear. Among the many cell populations that can serve as targets or relays for the pheromonal information in the hypothalamus are GnRH cells or the recently discovered Kispeptin population which have been showed to be activated after pheromonal activation. However, many works will be needed before having a definitive picture.
Rantala, Markus J; Vainikka, Anssi; Kortet, Raine
The immunocompetence handicap hypothesis postulates that secondary sexual traits are honest signals of mate quality because the hormones (e.g. testosterone) needed to develop secondary sexual traits have immunosuppressive effects. The best support for predictions arising from the immunocompetence handicap hypothesis so far comes from studies of insects, although they lack male-specific hormones such as testosterone. In our previous studies, we found that female mealworm beetles prefer pheromones of immunocompetent males. Here, we tested how juvenile hormone (JH) affects male investment in secondary sexual characteristics and immune functions in the mealworm beetle, Tenebrio molitor. We injected male mealworm beetles with JH (type III) and found that injection increased the attractiveness of male pheromones but simultaneously suppressed immune functions (phenoloxidase activity and encapsulation). Our results suggest that JH, which is involved in the control of reproduction and morphogenesis, also plays a central role in the regulation of a trade-off between the immune system and sexual advertisement in insects. Thus, the results reflect a general mechanism by which the immunocompetence handicap hypothesis may work in insects. PMID:14613612
Andreev, D; Breilid, H; Kirkendall, L; Brun, L O; ffrench-Constant, R H
The coffee berry borer beetle Hypothenemus hampei (Ferrari) (Curculionidae: Scolytinae) is the major insect pest of coffee and has spread to most of the coffee-growing countries of the world. This beetle also displays an unusual life cycle, with regular sibling mating. This regular inbreeding and the population bottlenecks occurring on colonization of new regions should lead to low levels of genetic diversity. We were therefore interested in determining the level of nucleotide variation in nuclear and mitochondrial genomes of this beetle worldwide. Here we show that two nuclear loci (Resistance to dieldrin and ITS2) are completely invariant, whereas some variability is maintained at a mitochondrial locus (COI), probably corresponding to a higher mutation rate in the mitochondrial genome. Phylogenetic analysis of the mitochondrial data shows only two clades of beetle haplotypes outside of Kenya, the proposed origin of the species. These data confirm that inbreeding greatly reduces nucleotide variation and suggest the recent global spread of only two inbreeding lines of this bark beetle.
Full Text Available By means of ethereal washing of insect pheromone glands of female moths, GC-MS detection along with microchemical reactions and electroantennogram (EAG survey, six economically important insect species were targeted for pheromone identification. The discovery of a natural pheromone inhibitor, chemo-selectivity and species isolation by pheromone will be described. The modified triple bond migration and triethylamine liganded vinyl cuprate were applied for achiral pheromone synthesis in double bond formation. Some optically active pheromones and their stereoisomers were synthesized through chiral pool or asymmetric synthesis. Some examples of chiral recognition of insects towards their chiral pheromones will be discussed. A CaH2 and silica gel catalyzed Sharpless Expoxidation Reaction was found in shortening the reaction time.
Koutroumpa, Fotini A; Jacquin-Joly, Emmanuelle
The moth sex pheromone communication is one of the most striking examples of chemical communication in the animal kingdom. Investigating the molecular mechanisms of pheromone biosynthesis in the female pheromone gland and of pheromone reception in the male antennae not only defines new concepts in signalling research but also opens new perspectives for insect control. In this mini-review, we use the cotton leafworm Spodoptera littoralis as a guideline to illustrate the recent advances gained in the understanding of moth sex pheromone communication. Copyright © 2014 Elsevier Masson SAS. All rights reserved.
Pierce, A M; Pierce, H D; Borden, J H; Oehlschlager, A C
Responses by five species of cucujid grain beetles (mixed-sex adults) to various volatiles were assessed by means of a two-choice, pitfall olfactometer. The test volatiles were short-chain alcohols and ketones known to be produced by fungi. Both racemic and chiral 1-octen-3-ols were strong attractants forCryptolestes ferrugineus (Stephens), as had been found previously forOryzaephilus surinamensis (L.),O. mercator (Fauvel), andAhasverus advena (Waltl). 3-Methylbutanol was another good attractant for these four cucujids, and it was the only test compound to whichCathartus quadricollis (Guér.) responded positively. 1-Octen-3-one, racemic 3-octanol, and 3-octanone showed various degrees of attractiveness for the former four species of cucujids.O. surinamensis was the only species of test beetle to show much positive response to 2-phenylethanol and ethanol. ForO. mercator andO. surinamensis, 3-methylbutanol enhanced positive response to their respective cucujolide aggregation pheromones.
Chang, Hetan; Liu, Yang; Yang, Ting; Pelosi, Paolo; Dong, Shuanglin; Wang, Guirong
Sexual communication in moths offers a simplified scenario to model and investigate insect sensory perception. Both PBPs (pheromone-binding proteins) and PRs (pheromone receptors) are involved in the detection of sex pheromones, but the interplay between them still remains largely unknown. In this study, we have measured the binding affinities of the four recombinant PBPs of Chilo suppressalis (CsupPBPs) to pheromone components and analogs and characterized the six PRs using the Xenopus oocytes expression system. Interestingly, when the responses of PRs were recorded in the presence of PBPs, we measured in several combinations a dramatic increase in signals as well as in sensitivity of such combined systems. Furthermore, the discrimination ability of appropriate combinations of PRs and PBPs was improved compared with the performance of PBPs or PRs alone. Besides further supporting a role of PBPs in the pheromone detection and discrimination, our data shows for the first time that appropriate combinations of PRs and PBPs improved the discrimination ability of PBPs or PRs alone. The variety of responses measured with different pairing of PBPs and PRs indicates the complexity of the olfaction system, which, even for the relatively simple task of detecting sex pheromones, utilises a highly sophisticated combinatorial approach.
Tabata, Jun; Narai, Yutaka; Sawamura, Nobuo; Hiradate, Syuntaro; Sugie, Hajime
Mealybugs, which include several agricultural pests, are small sap feeders covered with a powdery wax. They exhibit clear sexual dimorphism; males are winged but fragile and short lived, whereas females are windless and less mobile. Thus, sex pheromones emitted by females facilitate copulation and reproduction by serving as a key navigation tool for males. Although the structures of the hitherto known mealybug pheromones vary among species, they have a common structural motif; they are carboxylic esters of monoterpene alcohols with irregular non-head-to-tail linkages. However, in the present study, we isolated from the Matsumoto mealybug, Crisicoccus matsumotoi (Siraiwa), a pheromone with a completely different structure. Using gas chromatography-mass spectrometry and nuclear magnetic resonance spectroscopy, we identified the pheromone as 3-methyl-3-butenyl 5-methylhexanoate. Its attractiveness to males was confirmed in a series of field trapping experiments involving comparison between the isolated natural product and a synthetic sample. This is the first report of a hemiterpene mealybug pheromone. In addition, the acid moiety (5-methylhexanoate) appears to be rare in insect pheromones.
Full Text Available To meet the growing need for raw materials to produce pellets and wood-based biofuels, trees killed by natural disturbances have increasingly been considered as potential feedstock in bioenergy development scenarios in the Western U.S. and Canada. While much research has focused on utilization of beetle-killed and fire-salvaged timber from federal lands in this region, small private landowners make up a large portion of land holdings in the Rocky Mountain Region and may also provide an important potential supply of uniform feedstock pellets in decentralized energy supply systems in the future. In this paper, we evaluated the quality of pellets produced from green, beetle-killed, and burned lodgepole pine with and without bark using a chipper, hammer mill, and pellet mill intended for use by small landowners. Results show that green, beetle-killed, and fire-salvaged lodgepole pine produced by small landowners, including material with bark, are suitable as feedstock for pellet production. Further, pellet quality can be varied through the blending of source lodgepole pine products when needed to meet pellet quality standards.
Full Text Available Social insects exhibit sophisticated communication by means of pheromones, one example of which is the use of alarm pheromones to alert nestmates for colony defense. We review recent advances in the understanding of the processing of alarm pheromone information in the ant brain. We found that information about formic acid and n-undecane, alarm pheromone components, is processed in a set of specific glomeruli in the antennal lobe of the ant Camponotus obscuripes. Alarm pheromone information is then transmitted, via projection neurons, to the lateral horn and the calyces of the mushroom body of the protocerebrum. In the lateral horn, we found a specific area where terminal boutons of alarm pheromone-sensitive projection neurons are more densely distributed than in the rest of the lateral horn. Some neurons in the protocerebrum responded specifically to formic acid or n-undecane and they may participate in the control of behavioral responses to each pheromone component. Other neurons, especially those originating from the mushroom body lobe, responded also to non-pheromonal odors and may play roles in integration of pheromonal and non-pheromonal signals. We found that a class of neurons receive inputs in the lateral horn and the mushroom body lobe and terminate in a variety of premotor areas. These neurons may participate in the control of aggressive behavior, which is sensitized by alarm pheromones and is triggered by non-pheromonal sensory stimuli associated with a potential enemy. We propose that the alarm pheromone processing system has evolved by differentiation of a part of general odor processing system.
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
Brouillard, B.; Mikkelson, K. M.; Dickenson, E.; Sharp, J.
Recent drought and warmer temperatures associated with climate change have caused increased pest-induced forest mortality with impacts on biogeochemical and hydrologic processes. To better understand the seasonal impacts of bark beetle infestation on water quality, samples were collected regularly over two overlapping snow free seasons at surface water intakes of six water treatment facilities in the Rocky Mountain region of Colorado displaying varying levels of bark beetle infestation (high >40%, moderate 20-40%, and low <20%). Organic carbon concentrations were typically 3 to 6 times higher in waters sourced from high beetle-impacted watersheds compared to moderate and low impact watersheds, revealing elevated specific ultraviolet absorbance, fluorescence, and humic-like intensity indicative of elevated aromatic carbon signatures. Accordingly, an increase in disinfection byproduct (DBP) formation potential of 400 to 600% was quantified when contrasted with watersheds containing less tree mortality. Beetle impact exasperated seasonal increases in carbon loading and DBP formation potential following both runoff and precipitation events indicating windows when enhanced water treatment may be utilized by water providers in highly infested regions. Additionally, elevated carbon concentrations throughout the summer and fall along with peaks following precipitation events provide evidence of shifting hydrologic flow paths in areas experiencing high forest mortality from decreased tree water uptake and interception. Collectively, these results demonstrate the need for continued watershed protection and monitoring with a changing climate as the resultant perturbations can have adverse effects on biogeochemistry and water quality in heavily impacted areas.
Zhang, Jin; Walker, William B; Wang, Guirong
Male moths detect and find their mates using species-specific sex pheromones emitted by conspecific females. Olfaction plays a vital role in this behavior. Since the first discovery of an insect sex pheromone from the silkmoth Bombyx mori, great efforts have been spent on understanding the sensing of the pheromones in vivo. Much progress has been made in elucidating the molecular mechanisms that mediate chemoreception in insects in the past few decades. In this review, we focus on pheromone reception and detection in moths, from the molecular to the behavioral level. We trace the information pathway from the capture of pheromone by male antennae, binding and transportation to olfactory receptor neurons, receptor activation, signal transduction, molecule inactivation, through brain processing and behavioral response. We highlight the impact of recent studies and also provide our insights into pheromone processing. © 2015 Elsevier Inc. All rights reserved.
Liu, X; Macaulay, E D; Pickett, J A
Pheromonal carbonyl compounds; (Z)-11-hexadecanal, (E)-citral, and 2-heptanone were treated with six alcohols to give acetals or ketals, some of which acted as propheromones by releasing the pheromonal carbonyl compounds in ultraviolet or simulated sunlight. Highest yields of pheromone were obtained from adducts prepared witho-nitrobenzyl alcohol ando-nitrophenylethane-1,2-diol. Adducts from (Z)-11-hexadecenal and these two alcohols were employed in lures to catch diamondback moths,Plutella xylostella (L.).
Andrew P Lerch
Full Text Available Fire injury can increase tree susceptibility to some bark beetles (Curculionidae, Scolytinae, but whether wildfires can trigger outbreaks of species such as mountain pine beetle (Dendroctonus ponderosae Hopkins is not well understood. We monitored 1173 lodgepole (Pinus contorta var. latifolia Doug. and 599 ponderosa (Pinus ponderosa Doug. ex Law pines for three years post-wildfire in the Uinta Mountains of northeastern Utah in an area with locally endemic mountain pine beetle. We examined how the degree and type of fire injury influenced beetle attacks, brood production, and subsequent tree mortality, and related these to beetle population changes over time. Mountain pine beetle population levels were high the first two post-fire years in lodgepole pine, and then declined. In ponderosa pine, populations declined each year after initial post-fire sampling. Compared to trees with strip or failed attacks, mass attacks occurred on trees with greater fire injury, in both species. Overall, a higher degree of damage to crowns and boles was associated with higher attack rates in ponderosa pines, but additional injury was more likely to decrease attack rates in lodgepole pines. In lodgepole pine, attacks were initially concentrated on fire-injured trees, but during subsequent years beetles attacked substantial numbers of uninjured trees. In ponderosa pine, attacks were primarily on injured trees each year, although these stands were more heavily burned and had few uninjured trees. In total, 46% of all lodgepole and 56% of ponderosa pines underwent some degree of attack. Adult brood emergence within caged bole sections decreased with increasing bole char in lodgepole pine but increased in ponderosa pine, however these relationships did not scale to whole trees. Mountain pine beetle populations in both tree species four years post-fire were substantially lower than the year after fire, and wildfire did not result in population outbreaks.
Lerch, Andrew P; Pfammatter, Jesse A; Bentz, Barbara J; Raffa, Kenneth F
Fire injury can increase tree susceptibility to some bark beetles (Curculionidae, Scolytinae), but whether wildfires can trigger outbreaks of species such as mountain pine beetle (Dendroctonus ponderosae Hopkins) is not well understood. We monitored 1173 lodgepole (Pinus contorta var. latifolia Doug.) and 599 ponderosa (Pinus ponderosa Doug. ex Law) pines for three years post-wildfire in the Uinta Mountains of northeastern Utah in an area with locally endemic mountain pine beetle. We examined how the degree and type of fire injury influenced beetle attacks, brood production, and subsequent tree mortality, and related these to beetle population changes over time. Mountain pine beetle population levels were high the first two post-fire years in lodgepole pine, and then declined. In ponderosa pine, populations declined each year after initial post-fire sampling. Compared to trees with strip or failed attacks, mass attacks occurred on trees with greater fire injury, in both species. Overall, a higher degree of damage to crowns and boles was associated with higher attack rates in ponderosa pines, but additional injury was more likely to decrease attack rates in lodgepole pines. In lodgepole pine, attacks were initially concentrated on fire-injured trees, but during subsequent years beetles attacked substantial numbers of uninjured trees. In ponderosa pine, attacks were primarily on injured trees each year, although these stands were more heavily burned and had few uninjured trees. In total, 46% of all lodgepole and 56% of ponderosa pines underwent some degree of attack. Adult brood emergence within caged bole sections decreased with increasing bole char in lodgepole pine but increased in ponderosa pine, however these relationships did not scale to whole trees. Mountain pine beetle populations in both tree species four years post-fire were substantially lower than the year after fire, and wildfire did not result in population outbreaks.
Xu Wei; Leal, Walter S.
Pheromone-binding proteins (PBPs) are involved in the uptake of pheromones from pores on the antennae, transport through an aqueous environment surrounding the olfactory receptor neurons, and fast delivery to pheromone receptors. We tested the hypothesis that a C-terminal segment and a flexible loop are involved in the release of pheromones to membrane-bound receptors. We expressed in Escherichia coli 11 mutants of the PBP from the silkworm moth, BmorPBP, taking into consideration structural differences between the forms with high and low binding affinity. The N-terminus was truncated and His-69, His-70 and His-95 at the base of a flexible loop, and a cluster of acidic residues at the C-terminus were mutated. Binding assays and circular dichroism analyses support a mechanism involving protonation of acidic residues Asp-132 and Glu-141 at the C-terminus and histidines, His-70 and His-95, in the base of a loop covering the binding pocket. The former leads to the formation of a new α-helix, which competes with pheromone for the binding pocket, whereas positive charge repulsion of the histidines opens the opposite side of the binding pocket
Hennig, Stefan; Clemens, André; Rödel, Gerhard; Ostermann, Kai
We report on a pheromone-based inter-species communication system, allowing for a controlled cell-cell communication between the two species Saccharomyces cerevisiae and Schizosaccharomyces pombe as a proof of principle. It exploits the mating response pathways of the two yeast species employing the pheromones, α- or P-factor, as signaling molecules. The authentic and chimeric pheromone-encoding genes were engineered to code for the P-factor in S. cerevisiae and the α-factor in S. pombe. Upon transformation of the respective constructs, cells were enabled to express the mating pheromone of the opposite species. The supernatant of cultures of S. pombe cells expressing α-factor were able to induce a G1 arrest in the cell cycle, a change in morphology to the typical shmoo effect and expression driven by the pheromone-responsive FIG1 promoter in S. cerevisiae. The supernatant of cultures of S. cerevisiae cells expressing P-factor similarly induced cell cycle arrest in G1, an alteration in morphology typical for mating as well as the activation of the pheromone-responsive promoters of the rep1 and sxa2 genes in a pheromone-hypersensitive reporter strain of S. pombe. Apparently, both heterologous pheromones were correctly processed and secreted in an active form by the cells of the other species. Our data clearly show that the species-specific pheromone systems of yeast species can be exploited for a controlled inter-species communication.
Group-living species produce signals that alter the behavior and even the physiology of their social partners. Social insects possess especially sophisticated chemical communication systems that govern every aspect of colony life, including the defining feature of eusociality: reproductive division...... of labor. Current evidence hints at the central importance of queen pheromones, but progress has been hindered by the fact that such pheromones have only been isolated in honeybees. In a pair of papers on the ant Lasius niger, we identified and investigated a queen pheromone regulating worker sterility...... with other studies, these results indicate that queen pheromones are honest signals of quality that simultaneously regulate multiple social behaviors....
Chen, Da-Song; Dai, Jian-Qing; Han, Shi-Chou
The diamondback moth was estimated to increase costs to the global agricultural economy as the global area increase of Brassica vegetable crops and oilseed rape. Sex pheromones traps are outstanding tools available in Integrated Pest Management for many years and provides an effective approach for DBM population monitoring and control. The ratio of two major sex pheromone compounds shows geographical variations. However, the limitation of our information in the DBM pheromone biosynthesis damp...
Arbellay, Estelle; Daniels, Lori D; Mansfield, Shawn D; Chang, Alice S
Both mountain pine beetle (MPB) Dendroctonus ponderosae Hopkins and fire leave scars with similar appearance on lodgepole pine Pinus contorta Dougl. ex Loud. var. latifolia Engelm. that have never been compared microscopically, despite the pressing need to determine the respective effects of MPB and fire injury on tree physiology. We analysed changes in wood formation in naturally caused scars on lodgepole pine, and tested the hypotheses that (i) MPB and fire injury elicit distinct anomalies in lodgepole pine wood and (ii) anomalies differ in magnitude and/or duration between MPB and fire. Mountain pine beetle and fire injury reduced radial growth in the first year post-injury. Otherwise, radial growth and wood density increased over more than 10 years in both MPB and fire scars. We found that the general increase in radial growth was of greater magnitude (up to 27%) and of longer duration (up to 5 years) in fire scars compared with MPB scars, as shown in earlywood width. We also observed that the increase in latewood density was of greater magnitude (by 12%) in MPB scars, but of longer duration (by 4 years) in fire scars. Crystallinity decreased following MPB and fire injury, while microfibril angle increased. These changes in fibre traits were of longer duration (up to 4 years) in MPB scars compared with fire scars, as shown in microfibril angle. We found no significant changes in carbon and nitrogen concentrations. In conclusion, we stress that reduced competition and resistance to cavitation play an important role alongside cambial injury in influencing the type and severity of changes. In addition, more research is needed to validate the thresholds introduced in this study. Our findings serve as a foundation for new protocols to distinguish between bark beetle and fire disturbance, which is essential for improving our knowledge of historical bark beetle and fire regimes, and their interactions. © The Author 2017. Published by Oxford University Press. All
Chen, Rui; Ren, Jing; Ge, Siqin; Hu, David
Beetles keep their wings folded and protected under a hard shell. In times of danger, they must unfold them rapidly in order for them to fly to escape. Moreover, they must do so across a range of body mass, from 1 mg to 10 grams. How can they unfold their wings so quickly? We use high-speed videography to record wing unfolding times, which we relate to the geometry of the network of blood vessels in the wing. Larger beetles have longer unfolding times. Modeling of the flow of blood through the veins successfully accounts for the wing unfolding speed of large beetles. However, smaller beetles have anomalously short unfolding times, suggesting they have lower blood viscosity or higher driving pressure. The use of hydraulics to unfold complex objects may have implications in the design of micro-flying air vehicles.
Dale, Holly; Runions, Adam; Hobill, David; Prusinkiewicz, Przemyslaw
Bark patterns are a visually important characteristic of trees, typically attributed to fractures occurring during secondary growth of the trunk and branches. An understanding of bark pattern formation has been hampered by insufficient information regarding the biomechanical properties of bark and the corresponding difficulties in faithfully modelling bark fractures using continuum mechanics. This study focuses on the genus Xanthorrhoea (grasstrees), which have an unusual bark-like structure composed of distinct leaf bases connected by sticky resin. Due to its discrete character, this structure is well suited for computational studies. A dynamic computational model of grasstree development was created. The model captures both the phyllotactic pattern of leaf bases during primary growth and the changes in the trunk's width during secondary growth. A biomechanical representation based on a system of masses connected by springs is used for the surface of the trunk, permitting the emergence of fractures during secondary growth to be simulated. The resulting fracture patterns were analysed statistically and compared with images of real trees. The model reproduces key features of grasstree bark patterns, including their variability, spanning elongated and reticulate forms. The patterns produced by the model have the same statistical character as those seen in real trees. The model was able to support the general hypothesis that the patterns observed in the grasstree bark-like layer may be explained in terms of mechanical fractures driven by secondary growth. Although the generality of the results is limited by the unusual structure of grasstree bark, it supports the hypothesis that bark pattern formation is primarily a biomechanical phenomenon.
Jeanne A Robert
Full Text Available The mountain pine beetle, Dendroctonus ponderosae, is a native species of bark beetle (Coleoptera: Curculionidae that caused unprecedented damage to the pine forests of British Columbia and other parts of western North America and is currently expanding its range into the boreal forests of central and eastern Canada and the USA. We conducted a large-scale gene expression analysis (RNA-seq of mountain pine beetle male and female adults either starved or fed in male-female pairs for 24 hours on lodgepole pine host tree tissues. Our aim was to uncover transcripts involved in coniferophagous mountain pine beetle detoxification systems during early host colonization. Transcripts of members from several gene families significantly increased in insects fed on host tissue including: cytochromes P450, glucosyl transferases and glutathione S-transferases, esterases, and one ABC transporter. Other significantly increasing transcripts with potential roles in detoxification of host defenses included alcohol dehydrogenases and a group of unexpected transcripts whose products may play an, as yet, undiscovered role in host colonization by mountain pine beetle.
McGovern, W.L.; McKibben, G.H.; Gueldner, R.C.; Cross, W.H.
The production of pheromone by Anthonomus grandis Boheman when treated with 10,000 rad of 60 Co gamma irradiation compared favorably with that of control weevils for 5 days; however, feeding (determined by frass collection) was reduced from day one. No direct correlation was found between production of pheromone and elimination of frass
While humans are highly dependent upon visual cues when in close proximity, smell also play a big role in sociosexual behaviours. There is an inherent difficulty in studying human pheromones because of the need for cleanliness and odourlessness in human participants. Pheromones are often divided by function into two: ...
Muller, Nicolas; Piel, Matthieu; Calvez, Vincent; Voituriez, Raphaël; Gonçalves-Sá, Joana; Guo, Chin-Lin; Jiang, Xingyu; Murray, Andrew; Meunier, Nicolas
Budding yeast cells exist in two mating types, a and α, which use peptide pheromones to communicate with each other during mating. Mating depends on the ability of cells to polarize up pheromone gradients, but cells also respond to spatially uniform fields of pheromone by polarizing along a single axis. We used quantitative measurements of the response of a cells to α-factor to produce a predictive model of yeast polarization towards a pheromone gradient. We found that cells make a sharp transition between budding cycles and mating induced polarization and that they detect pheromone gradients accurately only over a narrow range of pheromone concentrations corresponding to this transition. We fit all the parameters of the mathematical model by using quantitative data on spontaneous polarization in uniform pheromone concentration. Once these parameters have been computed, and without any further fit, our model quantitatively predicts the yeast cell response to pheromone gradient providing an important step toward understanding how cells communicate with each other.
Suckling, David Maxwell; Stringer, Lloyd D; Jiménez-Pérez, Alfredo; Walter, Gimme H; Sullivan, Nicola; El-Sayed, Ashraf M
Habituation to sex pheromones is one of the key mechanisms in mating disruption, an insect control tactic. Male moths often show reduced sexual response after pre-exposure to female sex pheromone. Mating disruption is relatively rare in insect orders other than Lepidoptera. As a positive control we confirmed habituation in a moth (Epiphyas postvittana) using 24 h pre-exposure to sex pheromone to reduce subsequent activation behaviour. We then tested the impact of pre-exposure to sex or trail pheromone on subsequent behavioural response with insects from three other orders. Similar pre-exposure for 24 h to either sex pheromone [Pseudococcus calceolariae (Homoptera) and apple leaf curling midge Dasineura mali (Diptera), or trail pheromone of Argentine ants (Linepithema humile (Hymenoptera)], followed by behavioural assay in clean air provided no evidence of habituation after pre-exposure in these latter cases. The moths alone were affected by pre-exposure to pheromone. For pests without habituation, sustained attraction to a point source may make lure and kill more economical. Improved knowledge of behavioural processes should lead to better success in pest management and mechanisms should be investigated further to inform studies and practical efforts generally enhancing effectiveness of pheromone-based management. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.
Hagström, Å.K; Liénard, M.A.; Groot, A.T.; Hedenström, E; Löfstedt, C.
Background: Sex pheromones are essential in moth mate communication. Information on pheromone biosynthetic genes and enzymes is needed to comprehend the mechanisms that contribute to specificity of pheromone signals. Most heliothine moths use sex pheromones with (Z)-11-hexadecenal as the major
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
Beutel, Rolf G.; Friedrich, Frank; Leschen, Richard A. B.
Here, we review Charles Darwin’s relation to beetles and developments in coleopteran systematics in the last two centuries. Darwin was an enthusiastic beetle collector. He used beetles to illustrate different evolutionary phenomena in his major works, and astonishingly, an entire sub-chapter is dedicated to beetles in “The Descent of Man”. During his voyage on the Beagle, Darwin was impressed by the high diversity of beetles in the tropics, and he remarked that, to his surprise, the majority of species were small and inconspicuous. However, despite his obvious interest in the group, he did not get involved in beetle taxonomy, and his theoretical work had little immediate impact on beetle classification. The development of taxonomy and classification in the late nineteenth and earlier twentieth century was mainly characterised by the exploration of new character systems (e.g. larval features and wing venation). In the mid-twentieth century, Hennig’s new methodology to group lineages by derived characters revolutionised systematics of Coleoptera and other organisms. As envisioned by Darwin and Ernst Haeckel, the new Hennigian approach enabled systematists to establish classifications truly reflecting evolution. Roy A. Crowson and Howard E. Hinton, who both made tremendous contributions to coleopterology, had an ambivalent attitude towards the Hennigian ideas. The Mickoleit school combined detailed anatomical work with a classical Hennigian character evaluation, with stepwise tree building, comparatively few characters and a priori polarity assessment without explicit use of the outgroup comparison method. The rise of cladistic methods in the 1970s had a strong impact on beetle systematics. Cladistic computer programs facilitated parsimony analyses of large data matrices, mostly morphological characters not requiring detailed anatomical investigations. Molecular studies on beetle phylogeny started in the 1990s with modest taxon sampling and limited DNA data
Beutel, Rolf G; Friedrich, Frank; Leschen, Richard A B
Here, we review Charles Darwin's relation to beetles and developments in coleopteran systematics in the last two centuries. Darwin was an enthusiastic beetle collector. He used beetles to illustrate different evolutionary phenomena in his major works, and astonishingly, an entire sub-chapter is dedicated to beetles in "The Descent of Man". During his voyage on the Beagle, Darwin was impressed by the high diversity of beetles in the tropics, and he remarked that, to his surprise, the majority of species were small and inconspicuous. However, despite his obvious interest in the group, he did not get involved in beetle taxonomy, and his theoretical work had little immediate impact on beetle classification. The development of taxonomy and classification in the late nineteenth and earlier twentieth century was mainly characterised by the exploration of new character systems (e.g. larval features and wing venation). In the mid-twentieth century, Hennig's new methodology to group lineages by derived characters revolutionised systematics of Coleoptera and other organisms. As envisioned by Darwin and Ernst Haeckel, the new Hennigian approach enabled systematists to establish classifications truly reflecting evolution. Roy A. Crowson and Howard E. Hinton, who both made tremendous contributions to coleopterology, had an ambivalent attitude towards the Hennigian ideas. The Mickoleit school combined detailed anatomical work with a classical Hennigian character evaluation, with stepwise tree building, comparatively few characters and a priori polarity assessment without explicit use of the outgroup comparison method. The rise of cladistic methods in the 1970s had a strong impact on beetle systematics. Cladistic computer programs facilitated parsimony analyses of large data matrices, mostly morphological characters not requiring detailed anatomical investigations. Molecular studies on beetle phylogeny started in the 1990s with modest taxon sampling and limited DNA data. This has
Nancy E. Gillette; John D. Stein; Donald R. Owen; Jeffrey N. Webster; Sylvia R. Mori
Two aerial applications of microencapsulated pheromone were conducted on five 20.2 ha plots to disrupt western pine shoot borer (Eucosma sonomana Kearfott) and ponderosa pine tip moth (Rhyacionia zowna (Kearfott): Lepidoptera: Tortricidae) orientation to pheromones and oviposition in ponderosa pine plantations in 2002 and 2004...
Full Text Available Windstorms, bark beetle outbreaks and fires are important natural disturbances in coniferous forests worldwide. Wind-thrown trees promote biodiversity and restoration within production forests, but also cause large economic losses due to bark beetle infestation and accelerated fungal decomposition. Such damaged trees are often removed by salvage logging, which leads to decreased biodiversity and thus increasingly evokes discussions between economists and ecologists about appropriate strategies. To reveal the reasons behind species loss after salvage logging, we used a functional approach based on four habitat-related ecological traits and focused on saproxylic beetles. We predicted that salvage logging would decrease functional diversity (measured as effect sizes of mean pairwise distances using null models as well as mean values of beetle body size, wood diameter niche and canopy cover niche, but would increase decay stage niche. As expected, salvage logging caused a decrease in species richness, but led to an increase in functional diversity by altering the species composition from habitat-filtered assemblages toward random assemblages. Even though salvage logging removes tree trunks, the most negative effects were found for small and heliophilous species and for species specialized on wood of small diameter. Our results suggested that salvage logging disrupts the natural assembly process on windthrown trees and that negative ecological impacts are caused more by microclimate alteration of the dead-wood objects than by loss of resource amount. These insights underline the power of functional approaches to detect ecosystem responses to anthropogenic disturbance and form a basis for management decisions in conservation. To mitigate negative effects on saproxylic beetle diversity after windthrows, we recommend preserving single windthrown trees or at least their tops with exposed branches during salvage logging. Such an extension of the green
Thorn, Simon; Bässler, Claus; Gottschalk, Thomas; Hothorn, Torsten; Bussler, Heinz; Raffa, Kenneth; Müller, Jörg
Windstorms, bark beetle outbreaks and fires are important natural disturbances in coniferous forests worldwide. Wind-thrown trees promote biodiversity and restoration within production forests, but also cause large economic losses due to bark beetle infestation and accelerated fungal decomposition. Such damaged trees are often removed by salvage logging, which leads to decreased biodiversity and thus increasingly evokes discussions between economists and ecologists about appropriate strategies. To reveal the reasons behind species loss after salvage logging, we used a functional approach based on four habitat-related ecological traits and focused on saproxylic beetles. We predicted that salvage logging would decrease functional diversity (measured as effect sizes of mean pairwise distances using null models) as well as mean values of beetle body size, wood diameter niche and canopy cover niche, but would increase decay stage niche. As expected, salvage logging caused a decrease in species richness, but led to an increase in functional diversity by altering the species composition from habitat-filtered assemblages toward random assemblages. Even though salvage logging removes tree trunks, the most negative effects were found for small and heliophilous species and for species specialized on wood of small diameter. Our results suggested that salvage logging disrupts the natural assembly process on windthrown trees and that negative ecological impacts are caused more by microclimate alteration of the dead-wood objects than by loss of resource amount. These insights underline the power of functional approaches to detect ecosystem responses to anthropogenic disturbance and form a basis for management decisions in conservation. To mitigate negative effects on saproxylic beetle diversity after windthrows, we recommend preserving single windthrown trees or at least their tops with exposed branches during salvage logging. Such an extension of the green-tree retention
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.
The southern pine beetle (SPB) is the most destructive forest insect in the South. The SPB attacks all species of southern pine, but loblolly and shortleaf are most susceptible. The Southern Pine Beetle Information System (SPBIS) is the computerized database used by the national forests in the Southern Region for tracking individual southern pine beetle infestations....
Adams, Aaron S; Aylward, Frank O; Adams, Sandye M; Erbilgin, Nadir; Aukema, Brian H; Currie, Cameron R; Suen, Garret; Raffa, Kenneth F
The mountain pine beetle, Dendroctonus ponderosae, is a subcortical herbivore native to western North America that can kill healthy conifers by overcoming host tree defenses, which consist largely of high terpene concentrations. The mechanisms by which these beetles contend with toxic compounds are not well understood. Here, we explore a component of the hypothesis that beetle-associated bacterial symbionts contribute to the ability of D. ponderosae to overcome tree defenses by assisting with terpene detoxification. Such symbionts may facilitate host tree transitions during range expansions currently being driven by climate change. For example, this insect has recently breached the historical geophysical barrier of the Canadian Rocky Mountains, providing access to näive tree hosts and unprecedented connectivity to eastern forests. We use culture-independent techniques to describe the bacterial community associated with D. ponderosae beetles and their galleries from their historical host, Pinus contorta, and their more recent host, hybrid P. contorta-Pinus banksiana. We show that these communities are enriched with genes involved in terpene degradation compared with other plant biomass-processing microbial communities. These pine beetle microbial communities are dominated by members of the genera Pseudomonas, Rahnella, Serratia, and Burkholderia, and the majority of genes involved in terpene degradation belong to these genera. Our work provides the first metagenome of bacterial communities associated with a bark beetle and is consistent with a potential microbial contribution to detoxification of tree defenses needed to survive the subcortical environment.
Korada, R.R.; Griepink, F.C.
Gas chromatography with simultaneous flame ionisation and electroantennographic detection (GCEAD) and gas chromatography with mass spectrometry analysis (GCMS) of abdominal extracts of adult male Dermestes haemorrhoidalis Kuster (Coleoptera: Dermestidae) revealed the presence of
Saavedra, Irene; Amo, Luisa
Chemical cues play a fundamental role in mate attraction and mate choice. Lepidopteran females, such as the winter moth (Operophtera brumata), emit pheromones to attract males in the reproductive period. However, these chemical cues could also be eavesdropped by predators. To our knowledge, no studies have examined whether birds can detect pheromones of their prey. O. brumata adults are part of the winter diet of some insectivorous tit species, such as the great tit (Parus major) and blue tit (Cyanistes caeruleus). We performed a field experiment aimed to disentangle whether insectivorous birds can exploit the pheromones emitted by their prey for prey location. We placed artificial larvae and a dispenser on branches of Pyrenean oak trees (Quercus pyrenaica). In half of the trees we placed an O. brumata pheromone dispenser and in the other half we placed a control dispenser. We measured the predation rate of birds on artificial larvae. Our results show that more trees had larvae with signs of avian predation when they contained an O. brumata pheromone than when they contained a control dispenser. Furthermore, the proportion of artificial larvae with signs of avian predation was greater in trees that contained the pheromone than in control trees. Our results indicate that insectivorous birds can exploit the pheromones emitted by moth females to attract males, as a method of prey detection. These results highlight the potential use of insectivorous birds in the biological control of insect pests.
Jéssica A Gomes-Rezende
Full Text Available Recent evidence suggests that Paracoccidioides species have the potential to undergo sexual reproduction, although no sexual cycle has been identified either in nature or under laboratory conditions. In the present work we detected low expression levels of the heterothallic MAT loci genes MAT1-1 and MAT1-2, the α-pheromone (PBα gene, and the α- and a-pheromone receptor (PREB and PREA genes in yeast and mycelia forms of several Paracoccidioides isolates. None of the genes were expressed in a mating type dependent manner. Stimulation of P. brasiliensis MAT1-2 strains with the synthetic α-pheromone peptide failed to elicit transcriptional activation of MAT1-2, PREB or STE12, suggesting that the strains tested are insensitive to α-pheromone. In order to further evaluate the biological functionality of the pair α-pheromone and its receptor, we took advantage of the heterologous expression of these Paracoccidioides genes in the corresponding S. cerevisiae null mutants. We show that S. cerevisiae strains heterologously expressing PREB respond to Pbα pheromone either isolated from Paracoccidioides culture supernatants or in its synthetic form, both by shmoo formation and by growth and cell cycle arrests. This allowed us to conclude that Paracoccidioides species secrete an active α-pheromone into the culture medium that is able to activate its cognate receptor. Moreover, expression of PREB or PBα in the corresponding null mutants of S. cerevisiae restored mating in these non-fertile strains. Taken together, our data demonstrate pheromone signaling activation by the Paracoccidioides α-pheromone through its receptor in this yeast model, which provides novel evidence for the existence of a functional mating signaling system in Paracoccidioides.
Full Text Available Abstract Background Fission yeast cells undergo sexual differentiation in response to nitrogen starvation. In this process haploid M and P cells first mate to form diploid zygotes, which then enter meiosis and sporulate. Prior to mating, M and P cells communicate with diffusible mating pheromones that activate a signal transduction pathway in the opposite cell type. The pheromone signalling orchestrates mating and is also required for entry into meiosis. Results Here we use DNA microarrays to identify genes that are induced by M-factor in P cells and by P-factor in M-cells. The use of a cyr1 genetic background allowed us to study pheromone signalling independently of nitrogen starvation. We identified a total of 163 genes that were consistently induced more than two-fold by pheromone stimulation. Gene disruption experiments demonstrated the involvement of newly discovered pheromone-induced genes in the differentiation process. We have mapped Gene Ontology (GO categories specifically associated with pheromone induction. A direct comparison of the M- and P-factor induced expression pattern allowed us to identify cell-type specific transcripts, including three new M-specific genes and one new P-specific gene. Conclusion We found that the pheromone response was very similar in M and P cells. Surprisingly, pheromone control extended to genes fulfilling their function well beyond the point of entry into meiosis, including numerous genes required for meiotic recombination. Our results suggest that the Ste11 transcription factor is responsible for the majority of pheromone-induced transcription. Finally, most cell-type specific genes now appear to be identified in fission yeast.
James Vaughn Kohl
Full Text Available Background: The prenatal migration of gonadotropin-releasing hormone (GnRH neurosecretory neurons allows nutrients and human pheromones to alter GnRH pulsatility, which modulates the concurrent maturation of the neuroendocrine, reproductive, and central nervous systems, thus influencing the development of ingestive behavior, reproductive sexual behavior, and other behaviors. Methods: This model details how chemical ecology drives adaptive evolution via: (1 ecological niche construction, (2 social niche construction, (3 neurogenic niche construction, and (4 socio-cognitive niche construction. This model exemplifies the epigenetic effects of olfactory/pheromonal conditioning, which alters genetically predisposed, nutrient-dependent, hormone-driven mammalian behavior and choices for pheromones that control reproduction via their effects on luteinizing hormone (LH and systems biology. Results: Nutrients are metabolized to pheromones that condition behavior in the same way that food odors condition behavior associated with food preferences. The epigenetic effects of olfactory/pheromonal input calibrate and standardize molecular mechanisms for genetically predisposed receptor-mediated changes in intracellular signaling and stochastic gene expression in GnRH neurosecretory neurons of brain tissue. For example, glucose and pheromones alter the hypothalamic secretion of GnRH and LH. A form of GnRH associated with sexual orientation in yeasts links control of the feedback loops and developmental processes required for nutrient acquisition, movement, reproduction, and the diversification of species from microbes to man. Conclusion: An environmental drive evolved from that of nutrient ingestion in unicellular organisms to that of pheromone-controlled socialization in insects. In mammals, food odors and pheromones cause changes in hormones such as LH, which has developmental affects on pheromone-controlled sexual behavior in nutrient-dependent reproductively
Imari Walker, Sara; Davies, Paul C W; Samantray, Prasant; Aharonov, Yakir
Quantum weak measurements with states both pre- and post-selected offer a window into a hitherto neglected sector of quantum mechanics. A class of such systems involves time dependent evolution with transitions possible. In this paper we explore two very simple systems in this class. The first is a toy model representing the decay of an excited atom. The second is the tunneling of a particle through a barrier. The post-selection criteria are chosen as follows: at the final time, the atom remains in its initial excited state for the first example and the particle remains behind the barrier for the second. We then ask what weak values are predicted in the physical environment of the atom (to which no net energy has been transferred) and in the region beyond the barrier (to which the particle has not tunneled). Thus, just as the dog that didn't bark in Arthur Conan Doyle's story Silver Blaze gave Sherlock Holmes meaningful information about the dog's non-canine environment, here we probe whether the particle that has not decayed or has not tunneled can provide measurable information about physical changes in the environment. Previous work suggests that very large weak values might arise in these regions for long durations between pre- and post-selection times. Our calculations reveal some distinct differences between the two model systems. (paper)
Li, Ke; Buchinger, Tyler J; Li, Weiming
Covering: up to 2018 Fish use a diverse collection of molecules to communicate with conspecifics. Since Karlson and Lüscher termed these molecules 'pheromones', chemists and biologists have joined efforts to characterize their structures and functions. In particular, the understanding of insect pheromones developed at a rapid pace, set, in part, by the use of bioassay-guided fractionation and natural product chemistry. Research on vertebrate pheromones, however, has progressed more slowly. Initially, biologists characterized fish pheromones by screening commercially available compounds suspected to act as pheromones based upon their physiological function. Such biology-driven screening has proven a productive approach to studying pheromones in fish. However, the many functions of fish pheromones and diverse metabolites that fish release make predicting pheromone identity difficult and necessitate approaches led by chemistry. Indeed, the few cases in which pheromone identification was led by natural product chemistry indicated novel or otherwise unpredicted compounds act as pheromones. Here, we provide a brief review of the approaches to identifying pheromones, placing particular emphasis on the promise of using natural product chemistry together with assays of biological activity. Several case studies illustrate bioassay-guided fractionation as an approach to pheromone identification in fish and the unexpected diversity of pheromone structures discovered by natural product chemistry. With recent advances in natural product chemistry, bioassay-guided fractionation is likely to unveil an even broader collection of pheromone structures and enable research that spans across disciplines.
Fink, Glenn A.; Berenhaut, Kenneth S.; Oehmen, Christopher S.
Natural multi-agent systems often rely on “correlated random walks” (random walks that are biased toward a current heading) to distribute their agents over a space (e.g., for foraging, search, etc.). Our contribution involves creation of a new movement and pheromone model that applies the concept of heading bias in random walks to a multi-agent, digital-ants system designed for cyber-security monitoring. We examine the relative performance effects of both pheromone and heading bias on speed of discovery of a target and search-area coverage in a two-dimensional network layout. We found that heading bias was unexpectedly helpful in reducing search time and that it was more influential than pheromone for improving coverage. We conclude that while pheromone is very important for rapid discovery, heading bias can also greatly improve both performance metrics.
Zhang, Qing-He; Aldrich, Jeffrey R
The synthetic aggregation pheromone of the large milkweed bug, Oncopeltus fasciatus (Dallas) (Lygaeinae), also attracted males of the plant bug, Phytocoris difficilis Knight (Miridae). Field testing partial blends against the six-component blend comprising the Oncopeltus pheromone showed that cross-attraction of P. difficilis males was due to synergism between (E)-2-octenyl acetate and (E,E)-2,4-hexadienyl acetate. Hexyl acetate was abundant in the metathoracic scent gland (MSG) secretion of P. difficilis males, but because female P. difficilis could not initially be found in the field, further combinatorial tests were guided by prior research on the pheromones of two Phytocoris species in the western United States. The combination of hexyl, (E)-2-hexenyl, and (E)-2-octenyl acetates was as attractive to P. difficilis males as the milkweed bug pheromone, yet no milkweed bugs were drawn to this blend. Gas chromatographic (GC)-electroantennographic detection (EAD) and GC-mass spectrometric (MS) analyses of female P. difficilis MSGs determined that their secretion contained predominantly hexyl, (E)-2-hexenyl, and (E)-2-octenyl acetates (all strongly EAD-active)-the latter two compounds found only in trace amounts from males-plus five minor female-specific compounds, three of which were EAD-active. (E,E)-2,4-Hexadienyl acetate was not detected from P. difficilis females or males. The blend of the three major components, hexyl, (E)-2-hexenyl, and (E)-2-octenyl acetates (2:1.5:1 by volume), was as attractive as the blend of all six EAD-active compounds identified from females, indicating that this ternary blend constitutes the sex pheromone of P. difficilis. Hexyl acetate with (E)-2-octenyl acetate also attracted males of another species, P. breviusculus Reuter, but addition of (E)-2-hexenyl acetate and/or (E,E)-2,4-hexadienyl acetate inhibited attraction of P. breviusculus males. Attraction of P. difficilis males occurred mainly during the first half of scotophase. The
Suckling, D.M.; Peck, R.W.; Stringer, L.D.; Snook, K.; Banko, P.C.
Trail pheromone disruption of invasive ants is a novel tactic that builds on the development of pheromone-based pest management in other insects. Argentine ant trail pheromone, (Z)-9-hexadecenal, was formulated as a micro-encapsulated sprayable particle and applied against Argentine ant populations in 400 m2 field plots in Hawai'i Volcanoes National Park. A widely dispersed point source strategy for trail pheromone disruption was used. Traffic rates of ants in bioassays of treated filter paper, protected from rainfall and sunlight, indicated the presence of behaviorally significant quantities of pheromone being released from the formulation for up to 59 days. The proportion of plots, under trade wind conditions (2-3 m s-1), with visible trails was reduced for up to 14 days following treatment, and the number of foraging ants at randomly placed tuna-bait cards was similarly reduced. The success of these trail pheromone disruption trials in a natural ecosystem highlights the potential of this method for control of invasive ant species in this and other environments. ?? Springer Science+Business Media, LLC 2010.
Full Text Available Male moths rely on olfactory cues to find females for reproduction. Males also use volatile plant compounds (VPCs to find food sources and might use host-plant odor cues to identify the habitat of calling females. Both the sex pheromone released by conspecific females and VPCs trigger well-described oriented flight behavior towards the odor source. Whereas detection and central processing of pheromones and VPCs have been thought for a long time to be highly separated from each other, recent studies have shown that interactions of both types of odors occur already early at the periphery of the olfactory pathway. Here we show that detection and early processing of VPCs and pheromone can overlap between the two sub-systems. Using complementary approaches, i.e. single-sensillum recording of olfactory receptor neurons, in vivo calcium imaging in the antennal lobe, intracellular recordings of neurons in the macroglomerular complex (MGC and flight tracking in a wind tunnel, we show that some plant odorants alone, such as heptanal, activate the pheromone-specific pathway in male Agrotis ipsilon at peripheral and central levels. To our knowledge, this is the first report of a plant odorant with no chemical similarity to the molecular structure of the pheromone, acting as a partial agonist of a moth sex pheromone.
Full Text Available ERK5 MAP kinase is highly expressed in the developing nervous system but absent in most regions of the adult brain. It has been implicated in regulating the development of the main olfactory bulb and in odor discrimination. However, whether it plays an essential role in pheromone-based behavior has not been established. Here we report that conditional deletion of the Mapk7 gene which encodes ERK5 in mice in neural stem cells impairs several pheromone-mediated behaviors including aggression and mating in male mice. These deficits were not caused by a reduction in the level of testosterone, by physical immobility, by heightened fear or anxiety, or by depression. Using mouse urine as a natural pheromone-containing solution, we provide evidence that the behavior impairment was associated with defects in the detection of closely related pheromones as well as with changes in their innate preference for pheromones related to sexual and reproductive activities. We conclude that expression of ERK5 during development is critical for pheromone response and associated animal behavior in adult mice.
Girma, A.; Skidmore, A.K.; Bie, de C.A.J.M.; Bongers, F.; Schlerf, M.
Quantification of chlorophyll content provides useful insight into the physiological performance of plants. Several leaf chlorophyll estimation techniques, using hyperspectral instruments, are available. However, to our knowledge, a non-destructive bark chlorophyll estimation technique is not
Girma Gebrekidan, A.; Skidmore, A.K.; de Bie, C.A.J.M.; Bongers, Frans; Schlerf, Martin; Schlerf, M.
Quantification of chlorophyll content provides useful insight into the physiological performance of plants. Several leaf chlorophyll estimation techniques, using hyperspectral instruments, are available. However, to our knowledge, a non-destructive bark chlorophyll estimation technique is not
Sattar, A.; Khattak, S.; Hamed, M.
In this report radiosensitivity of red beetle has been discussed. Red flour beetle is the most injurious pest causing great losses to stored grain. Radiation is one of the best tools of insect control. Different radiation doses (50 to 200 krads) were employed for different age groups from 1 to 60 days. It is concluded from these results that 200 krad radiation dose caused 100% mortality in red beetle in all age group. (A.B.)
Wertheim, B.; Dicke, M.; Vet, L.E.M.
We explored behavioural plasticity in the use of aggregation pheromone in the fruit fly Drosophila melanogaster Meigen (Diptera: Drosophilidae). Based on previous field observations, we formulated two hypotheses on a benefit of using aggregation pheromone for aggregated oviposition. One hypothesis
Wertheim, B; Dicke, Marcel; Vet, LEM
We explored behavioural plasticity in the use of aggregation pheromone in the fruit fly Drosophila melanogaster Meigen (Diptera: Drosophilidae). Based on previous field observations, we formulated two hypotheses on a benefit of using aggregation pheromone for aggregated oviposition. One hypothesis
ABSTRACT. The study was aimed at screening the stem bark extracts of Faidherbia albida and Psidium guajava for synergistic antibacterial effect against methicillin resistant Staphylococcus aureus (MRSA). The powdered plant materials were extracted with methanol using cold maceration technique and the extracts were ...
van Oudenhove, Louise; Billoir, Elise; Boulay, Raphaël; Bernstein, Carlos; Cerdá, Xim
In Mediterranean habitats, temperature affects both ant foraging behaviour and community structure. Many studies have shown that dominant species often forage at lower temperature than subordinates. Yet, the factors that constrain dominant species foraging activity in hot environments are still elusive. We used the dominant ant Tapinoma nigerrimum as a model species to test the hypothesis that high temperatures hinder trail following behaviour by accelerating pheromone degradation. First, field observations showed that high temperatures (> 30°C) reduce the foraging activity of T. nigerrimum independently of the daily and seasonal rhythms of this species. Second, we isolated the effect of high temperatures on pheromone trail efficacy from its effect on worker physiology. A marked substrate was heated during 10 min (five temperature treatments from 25°C to 60°C), cooled down to 25°C, and offered in a test choice to workers. At hot temperature treatments (>40°C), workers did not discriminate the previously marked substrate. High temperatures appeared therefore to accelerate pheromone degradation. Third, we assessed the pheromone decay dynamics by a mechanistic model fitted with Bayesian inference. The model predicted ant choice through the evolution of pheromone concentration on trails as a function of both temperature and time since pheromone deposition. Overall, our results highlighted that the effect of high temperatures on recruitment intensity was partly due to pheromone evaporation. In the Mediterranean ant communities, this might affect dominant species relying on chemical recruitment, more than subordinate ant species, less dependent on chemical communication and less sensitive to high temperatures.
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...
Sharon Hood; Anna Sala; Emily K. Heyerdahl; Marion Boutin
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...
Menéndez, E.; Ramírez-Bahena, M.H.; Fabryová, Anna; Igual, J.M.; Benada, Oldřich; Mateos, P.; Peix, A.; Kolařík, Miroslav; García-Fraile, Paula
Roč. 65, September (2015), s. 2852-2858 ISSN 1466-5026 R&D Projects: GA MŠk(CZ) EE2.3.30.0003 Institutional support: RVO:61388971 Keywords : CURCULIONIDAE SCOLYTINAE * NUCLEOTIDE-SEQUENCES * DENDROCTONUS-RHIZOPHAGUS Subject RIV: EE - Microbiology, Virology Impact factor: 2.439, year: 2015
Menéndez, E.; Ramírez-Bahena, M.H.; Fabryová, A.; Igual, J.M.; Benada, Oldřich
Roč. 65, SEP 2015 (2015), s. 2852-2858 ISSN 1466-5026 R&D Projects: GA MŠk(CZ) EE2.3.30.0003 Institutional support: RVO:61388971 Keywords : CURCULIONIDAE SCOLYTINAE * NUCLEOTIDE-SEQUENCES * DENDROCTONUS-RHIZOPHAGUS Subject RIV: EE - Microbiology, Virology Impact factor: 2.439, year: 2015
Marini, Lorenzo; Økland, Bjørn; Jönsson, Anna Maria
of warming temperatures and rainfall deficit. The large surplus of breeding material likely boosted I. typographus population size above the density threshold required to colonize and kill healthy trees irrespective of other climate triggers. Importantly, we found strong negative density dependence in I....... 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....
Doležal, Petr; Okrouhlík, Jan; Davídková, Markéta
Roč. 113, JAN 07 (2016), s. 1-8 E-ISSN 1802-8829 Grant - others:Forests of the Czech Republic(CZ) 08/2009; MŠMT(CZ) LH12098 Institutional support: RVO:60077344 Keywords : Coleoptera * Scolytidae * Ips typographus Subject RIV: EH - Ecology, Behaviour Impact factor: 1.167, year: 2016 http://www.eje.cz/pdfs/eje/2016/01/01.pdf
Grucmanová, Š.; Holuša, J.; Nermuť, Jiří
Roč. 138, č. 10 (2014), s. 723-732 ISSN 0931-2048 Grant - others:Czech University of Life Sciences in Prague(CZ) 20134325; Czech University of Life Sciences in Prague(CZ) 20124302 Institutional support: RVO:60077344 Keywords : galleries * generations * Ips duplicatus Subject RIV: EH - Ecology, Behaviour Impact factor: 1.650, year: 2014 http://onlinelibrary.wiley.com/doi/10.1111/jen.12142/epdf
In a low-temperature scanning electron microscopy study aimed at determining whether the coffee berry borer (Hypothenemus hampei (Ferrari); Coleoptera: Curculionidae: Scolytinae) possesses mycangia, we fortuitously detected the mesothoracic spiracles, which are usually concealed. The mesothoracic s...
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...
Chris Hayes; Tom DeGomez; Karen Clancy; Joel McMillin; John Anhold
(Please note, this is an abstract only) Phloeosinus-caused mortality of Arizona cypress, (Cupressus arizonica), oneseed juniper, (Juniperus monosperma) and alligator juniper, (J. deppeana) has been observed at high levels in Arizona during the past 3 years. Currently, there are limited preventative measures to protect high-value cypress and juniper trees against...
K.D. Klepzig; J.C. Moser; M.J. Lombardero; M.P. Ayres; R.W. Hofstetter; C.J. Walkinshaw
Insect-fungal complexes provide challenging and fascinating systems for the study of biotic interactions between plants. plant pathogens, insect vectors and other associated organisms. The types of interactions among these organisms (mutualism. antagonism. parasitism. phoresy. etc.) are as variable as the range of organisms involved (plants, fungi, insects. mites. etc...
Richard T. Wilkens; Matthew P. Ayres; Peter L. Lorio; John D. Hodges
Our results indicate that increased nutrient availability leads to an increase in growth and a reduction in resin-based defenses.Because of this, we recommend that foresters and planners consider the effect of fertilization and site fertility on both tree growth and SPB risk.Unfortunately, increased tree growth may frequently be associated with increased SPB risk.The...
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
Händel, U.; Wegensteiner, R.; Weiser, Jaroslav; Žižka, Zdeněk
Roč. 76, - (2003), s. 22-32 ISSN 1436-5693 Institutional research plan: CEZ:AV0Z5020903; CEZ:AV0Z5007907 Keywords : Ips-typographus Coleoptera- mickrospora Subject RIV: EE - Microbiology, Virology Impact factor: 0.197, year: 2003
Kalinová, Blanka; Břízová, Radka; Knížek, M.; Turčáni, M.; Hoskovec, Michal
Roč. 8, č. 4 (2014), s. 305-316 ISSN 1872-8855 Institutional support: RVO:61388963 Keywords : Ips typographus * Picea abies * host selection * semiochemicals * GC-EAD * GC9GC/TOFMS Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 1.462, year: 2014
Jakuš, Rastislav; Blaženec, Miroslav
We carried out an experiment with using the entomopathogenic fungus Beauveria bassiana (Bals.) Vuill. for sanitation of active infested trees. We used 15 active infested trees from which 5 stems were treated with an insecticide, 5 were treated with solution of the tested entomopathogenic fungus and 5 were left as control. The used insecticide was pyretroid Fury 10 EW. We used a biopreparation based on the entomopathogenic fungus B. bassiana in form of wettable powder. The material was diluted...
Macek, Martin; Wild, Jan; Kopecký, Martin; Červenka, J.; Svoboda, M.; Zenáhlíková, J.; Brůna, Josef; Mosandl, R.; Fischer, A.
Roč. 27, č. 1 (2017), s. 156-167 ISSN 1051-0761 R&D Projects: GA ČR GAP504/10/0843 Institutional support: RVO:67985939 Keywords : advance regeneration * growth function * Ips typographus * mortality * norway spruce Subject RIV: EH - Ecology, Behaviour OBOR OECD: Ecology Impact factor: 4.314, year: 2016
Kolařík, Miroslav; Hulcr, J.; Tisserat, N.; De Beer, W.; Kostovčík, Martin; Kolaříková, Zuzana; Seybold, S.J.; Rizzo, D.M.
Roč. 109, č. 2 (2017), s. 185-199 ISSN 0027-5514 R&D Projects: GA ČR(CZ) GJ16-15293Y; GA MŠk(CZ) LO1509 Institutional support: RVO:61388971 ; RVO:67985939 Keywords : Entomochoric fungi * Geosmithia morbida * Pityophthorus juglandis Subject RIV: EE - Microbiology, Virology; EH - Ecology, Behaviour (BU-J) OBOR OECD: Microbiology; Ecology (BU-J) Impact factor: 2.550, year: 2016
Full Text Available The biological characters of Scolytus nitidus were investigated both in the field and in thelaboratory as well. This common shot-hole borer overwinters in larval stage on apple trees in Kashmir.After emergence the adults fly to suitable trees and undergo maturation feeding for 4-6 days. Thecopulation takes place at the entrance hole. The maternal gallery is one armed longitudinal, in average4.6 cm long. The female lays 52 eggs on an average. The eggs hatch in 5 to 7 days. The larvae have 5instars and complete their development in 38 to 50 days constructing larval galleries 5-8 cm in length.The larvae pupate for 6-18 days and finally the adults emerge to attack new suitable trees. The adultslive for 45-60 days and the total life-span of this species ranges from 97 to 124 days. The seasonaldistribution of various life stages and the number of generations were also recorded.
... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Tomato pinworm insect pheromone... RESIDUES IN FOOD Exemptions From Tolerances § 180.1064 Tomato pinworm insect pheromone; exemption from the... residues of both components of the tomato pinworm insect pheromone (E)-4-tridecen-1-yl acetate and (Z)-4...
Vander Meer, Robert K; Preston, Catherine A; Choi, Man-Yeon
Alarm pheromones in social insects are an essential part of a complex of pheromone interactions that contribute to the maintenance of colony integrity and sociality. The alarm pheromones of ants were among the first examples of animal pheromones identified, primarily because of the large amount of chemical produced and the distinctive responses of ants to the pheromone. However, the alarm pheromone of the fire ant, Solenopsis invicta, eluded identification for over four decades. We identified 2-ethyl-3,6-dimethylpyrazine as an alarm pheromone component of S. invicta. Worker fire ants detect the pyrazine alarm pheromone at 30 pg/ml, which is comparable to alarm pheromone sensitivities reported for other ant species. The source of this alarm pheromone are the mandibular glands, which, in fire ants, are not well developed and contain only about 300 pg of the compound, much less than the microgram quantities of alarm pheromones reported for several other ant species. Female and male sexuals and workers produce the pyrazine, which suggests that it may be involved in fire ant mating flight initiation, as well as the typical worker alarm response. This is the first report of 2-ethyl-3,6-dimethylpyrazine from a Solenopsis species and the first example of this alkaloid functioning as an alarm pheromone.
... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Plant volatiles and pheromone... RESIDUES IN FOOD Exemptions From Tolerances § 180.1080 Plant volatiles and pheromone; exemptions from the... pheromone Z-2-isopropenyl-1-methylcyclobutaneethanol; Z-3,3-dimethyl-Δ1,β-cyclohexaneethanol; Z-3,3-dimethyl...
Full Text Available Pheromonal communication is crucial with regard to mate choice in many animals including insects. Drosophila melanogaster flies produce a pheromonal bouquet with many cuticular hydrocarbons some of which diverge between the sexes and differently affect male courtship behavior. Cuticular pheromones have a relatively high weight and are thought to be -- mostly but not only -- detected by gustatory contact. However, the response of the peripheral and central gustatory systems to these substances remains poorly explored. We measured the effect induced by pheromonal cuticular mixtures on (i the electrophysiological response of peripheral gustatory receptor neurons, (ii the calcium variation in brain centers receiving these gustatory inputs and (iii the behavioral reaction induced in control males and in mutant desat1 males, which show abnormal pheromone production and perception. While male and female pheromones induced inhibitory-like effects on taste receptor neurons, the contact of male pheromones on male fore-tarsi elicits a long-lasting response of higher intensity in the dedicated gustatory brain center. We found that the behavior of control males was more strongly inhibited by male pheromones than by female pheromones, but this difference disappeared in anosmic males. Mutant desat1 males showed an increased sensitivity of their peripheral gustatory neurons to contact pheromones and a behavioral incapacity to discriminate sex pheromones. Together our data indicate that cuticular hydrocarbons induce long-lasting inhibitory effects on the relevant taste pathway which may interact with the olfactory pathway to modulate pheromonal perception.
... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Arthropod pheromones; exemption from... FOOD Exemptions From Tolerances § 180.1124 Arthropod pheromones; exemption from the requirement of a tolerance. Arthropod pheromones, as described in § 152.25(b) of this chapter, when used in retrievably sized...
Holter, Peter; Scholtz, Clarke H.
Most adult coprophagous beetles feed on fresh dung of mammalian herbivores, confining ingestion to small particles with measured maximum diameters from 2-5 to 130 µm, according to body size and kind of beetle. This study explores benefits and costs of selective feeding in a ‘typical' dung beetle...... that of elephant and rhino (40-58%) was available to selective feeders. 3. Nitrogen concentrations were high - and C/N ratios low - in most types of bulk dung compared with the average food of terrestrial detritivores or herbivores. Exceptions were elephant and rhino dung with low nitrogen concentrations and high...... C/N ratios. 4. Estimated C/N ratios of 13-39 in bulk dung (sheep-elephant) were decreased by selective feeding to 7.3-12.6 in the ingested material. In assimilated food, ratios are probably only 5-7, as most assimilable nitrogen and carbon may be of microbial origin. If so, the assimilable food...
The aetiology of anorexia nervosa is exocrinological. This notion is supported by physical evidence in animal models with directly comparable symptomatology. Anorexia nervosa (AN) syndrome would be a puberty delay caused by reception and autoreception of conspecific pheromone emissions: a pheromone-induced puberty delay (PIPD). As such, it would be amenable to medical treatment drawing from forty years of research in animals. This hypothesis is testable. For instance, since food ad libitum is a prerequisite for PIPD, occasional supervised fasting in healthy peripuberal subjects should prevent AN. Besides, tolerating an untestable thought disease (1,2) with symptoms of a curable well-understood animal condition would be anti-scientific and perpetuates medical disaster. Even their endocrinologies are identical. Pheromone feedback tunes animal appetites and immunity to available resources and prospects. In addition to timing puberty, pheromones regulate fertility. Pheromones will probably be implicated in the aetiology of the psychiatric and autoimmune diseases. This is the second in a series of twelve papers to explore this contention systematically. (c) 2000 Harcourt Publishers Ltd Copyright 2000 Harcourt Publishers Ltd.
Johannes L.M. Steidle
Full Text Available Despite the sanitary importance of the European house dust mite Dermatophagoides pteronyssinus (Trouessart, 1897, the pheromonal communication in this species has not been sufficiently studied. Headspace analysis using solid phase micro extraction (SPME revealed that nerol, neryl formate, pentadecane, (6Z,9Z-6,9-heptadecadiene, and (Z-8-heptadecene are released by both sexes whereas neryl propionate was released by males only. Tritonymphs did not produce any detectable volatiles. In olfactometer experiments, pentadecane and neryl propionate were attractive to both sexes as well as to tritonymphs. (Z-8-heptadecene was only attractive to male mites. Therefore it is discussed that pentadecane and neryl propionate are aggregation pheromones and (Z-8-heptadecene is a sexual pheromone of the European house dust mite D. pteronyssinus. To study the potential use of pheromones in dust mite control, long-range olfactometer experiments were conducted showing that mites can be attracted to neryl propionate over distances of at least 50 cm. This indicates that mite pheromones might be useable to monitor the presence or absence of mites in the context of control strategies.
Martínez-García, Fernando; Martínez-Ricós, Joana; Agustín-Pavón, Carmen; Martínez-Hernández, Jose; Novejarque, Amparo; Lanuza, Enrique
In rodents, sexual advertisement and gender recognition are mostly (if not exclusively) mediated by chemosignals. Specifically, there is ample evidence indicating that female mice are 'innately' attracted by male sexual pheromones that have critical non-volatile components and are detected by the vomeronasal organ. These pheromones can only get access to the vomeronasal organ by active pumping mechanisms that require close contact with the source of the stimulus (e.g. urine marks) during chemoinvestigation. We have hypothesised that male sexual pheromones are rewarding to female mice. Indeed, male-soiled bedding can be used as a reinforcer to induce conditioned place preference, provided contact with the bedding is allowed. The neural mechanisms of pheromone reward seem, however, different from those employed by other natural reinforcers, such as the sweetness or postingestive effects of sucrose. In contrast to vomeronasal-detected male sexual pheromones, male-derived olfactory stimuli (volatiles) are not intrinsically attractive to female mice. However, after repeated exposure to male-soiled bedding, intact female mice develop an acquired preference for male odours. On the contrary, in females whose accessory olfactory bulbs have been lesioned, exposure to male-soiled bedding induces aversion to male odorants. These considerations, together with data on the different properties of olfactory and vomeronasal receptors, lead us to make a proposal for the complementary roles that the olfactory and vomeronasal systems play in intersexual attraction and in other forms of intra- or inter-species communication.
Maya Nehme; Melody Keena; Aijun Zhang; Alan Sawyer; Kelli. Hoover
An operationally effective trap to monitor the Asian longhorned beetle (Anoplophora glabripennis or ALB) has been a goal of the ALB eradication program since the first beetle was found in New York in 1996. Ground surveying is only ~20 percent effective at identifying infested trees and, although tree climbing is more effective, it is also...
Stridulation behavior has been reported for adults and larvae of many dynastids. This report describes acoustic recordings and analyses of stridulations by larvae of two Southeastern Asia rhinoceros beetle species and by adults of the coconut rhinoceros beetle. The behavioral context of the strid...
Foster, Stephen P; Anderson, Karin G; Casas, Jérôme
Moths are exemplars of chemical communication, especially with regard to specificity and the minute amounts they use. Yet, little is known about how females manage synthesis and storage of pheromone to maintain release rates attractive to conspecific males and why such small amounts are used. We developed, for the first time, a quantitative model, based on an extensive empirical data set, describing the dynamical relationship among synthesis, storage (titer) and release of pheromone over time in a moth (Heliothis virescens). The model is compartmental, with one major state variable (titer), one time-varying (synthesis), and two constant (catabolism and release) rates. The model was a good fit, suggesting it accounted for the major processes. Overall, we found the relatively small amounts of pheromone stored and released were largely a function of high catabolism rather than a low rate of synthesis. A paradigm shift may be necessary to understand the low amounts released by female moths, away from the small quantities synthesized to the (relatively) large amounts catabolized. Future research on pheromone quantity should focus on structural and physicochemical processes that limit storage and release rate quantities. To our knowledge, this is the first time that pheromone gland function has been modeled for any animal.
Egel, R; Willer, M; Kjaerulff, S
We describe a rapid, sensitive and semi-quantitative plate assay for monitoring pheromone activity in the fission yeast Schizosaccharomyces pombe. It is based on the observation that meiosis requires stimulation by pheromone and exploits diploid strains that will only sporulate after addition...... of exogenous pheromone. The tester strains are heterozygous for mating type, are non-switching, and are mutated in one of the early subfunctions (either mat1-Mc or mat1-Pc), so that meiosis is only induced after exposure to exogenous pheromone (M-factor or P-factor, respectively). Pheromone activity...
McClure, Allison W.; Minakova, Maria; Dyer, Jayme M.; Zyla, Trevin R.; Elston, Timothy C.; Lew, Daniel J.
Summary Yeast cells track gradients of pheromones to locate mating partners. Intuition suggests that uniform distribution of pheromone receptors over the cell surface would yield optimal gradient sensing. However, yeast cells display polarized receptors. The benefit of such polarization was unknown. During gradient tracking, cell growth is directed by a patch of polarity regulators that wanders around the cortex. Patch movement is sensitive to pheromone dose, with wandering reduced on the up-gradient side of the cell, resulting in net growth in that direction. Mathematical modeling suggests that active receptors and associated G proteins lag behind the polarity patch and act as an effective drag on patch movement. In vivo, the polarity patch is trailed by a G protein-rich domain, and this polarized distribution of G proteins is required to constrain patch wandering. Our findings explain why G protein polarization is beneficial, and illuminate a novel mechanism for gradient tracking. PMID:26609960
Vogt, R.G.; Prestwich, G.D.; Riddiford, L.M.
A tritium-labeled photoaffinity analog of a moth pheromone was used to covalently modify pheromone-selective binding proteins in the antennal sensillum lymph and sensory dendritic membranes of the male silk moth, Antheraea polyphemus. This analog, (E,Z)-6,11-[ 3 H]hexadecadienyl diazoacetate, allowed visualization of a 15-kilodalton soluble protein and a 69-kilodalton membrane protein in fluorescence autoradiograms of electrophoretically separated antennal proteins. Covalent modification of these proteins was specifically reduced when incubation and UV irradiation were conducted in the presence of excess unlabeled pheromone, (E,Z)-6,11-hexadecadienyl acetate. These experiments constitute the first direct evidence for a membrane protein of a chemosensory neuron interacting in a specific fashion with a biologically relevant odorant
Hohlemwerger, Sandra Virginia Alves; Sales, Edijane Matos; Costa, Rafael dos Santos; Velozo, Eudes da Silva; Guedes, Maria Lenise da Silva
In 1959, Gottlieb and Antonaccio published a study reporting the occurrence of lignan sesamin and triterpene lupeol in Zanthoxylum tingoassuiba. In this work we describe the phytochemical study of the root bark of the Z. tingoassuiba which allowed the identification of the lupeol, sesamin, and alkaloids dihydrochelerythrine, chelerythrine, anorttianamide, cis-N-methyl-canadin, predicentine, 2, 3-methylenedioxy-10,11-dimethoxy-tetrahydro protoberberine. The investigation of hexane and methanol extracts of the root bark of Z. rhoifolium and Z. stelligerum also investigated showed the presence of alkaloids dihydrochelerythrine, anorttianamide, cis-N-methyl-canadine, 7,9-dimethoxy-2,3- methylenedioxybenzophen anthridine and angoline. The occurrence of 2,3-methylenedioxy-10,11-dimethoxy-tetrahydro protoberberine is first described in Z. tingoassuiba and Z. stelligerum. This is also the first report of the presence of hesperidin and neohesperidin in roots of Z. stelligerum (author)
Larsen, Hanne Marie Ellegård; Rasmussen, Hanne Nina; Nord-Larsen, Thomas
The water holding capacity of bark in seven Danish angiosperm trees was examined. The aim of the study was (1) to examine height trends and (2) bark thickness trends in relation to the water holding capacity and (3) to determine interspecific differences. The wet-weight and dry-weight of a total...... number of 427 bark samples were measured. The water holding capacity was calculated as the difference between wet-weight and dry-weight per wet-weight. The water holding capacity increased with elevation in most tree species and contrary to the expectation, thinner bark generally had a higher water...... holding capacity. Differences in the water holding capacity of bark may influence the occurrence and distribution of a wide range of bark-living organisms including the distribution of corticolous lichens....
Md. Azharul Islam
Full Text Available The insect’s world is filled with many odors. Insects use these odors to cue them in a variety of complex social behaviors, including courtship, mating, and egg laying. Scientists and pest control specialists have known about these complex communication systems for decades. The main aim of this study was to visualize the availability, trends and differences in the sources of pheromone control in agricultural growth of Bangladesh. It also concerned on constrains and present use of pheromone and their possible recommendation on behalf of Bangladesh agriculture. It concentrated on the data during last three decades (1980-2010, comprising status of pheromone use in Bangladesh agriculture and its future. Review revealed that Bangladesh has been enormously successful in increasing pheromone use in agricultural production (especially for vegetables. Understanding of the nature of pheromones and their potential for pest control along with the future prospective of pheromone technique in agriculture were stated. Since the pheromone, technologies for control of major crop pests in Bangladesh are still limited. So that this review emphasized on more attention to the authority to increase the research works and project facilities related to develop and promote pheromone techniques. It is highly recommended to increase availability of pheromone in market, more investment in research and development, introduction of newly identified pheromone for specific pest, to assist government and non-government organizations to work with farmers to reduce harmful insecticide use and promote pheromone tactics as one part of integrated crop management (ICM.
Unluturk, Bige D; Akyildiz, Ian F
A new track in molecular communication is using pheromones which can scale up the range of diffusion-based communication from μm meters to meters and enable new applications requiring long range. Pheromone communication is the emission of molecules in the air which trigger behavioral or physiological responses in receiving organisms. The objective of this paper is to introduce a new end-to-end model which incorporates pheromone behavior with communication theory for plants. The proposed model includes both the transmission and reception processes as well as the propagation channel. The transmission process is the emission of pheromones from the leaves of plants. The dispersion of pheromones by the flow of wind constitutes the propagation process. The reception process is the sensing of pheromones by the pheromone receptors of plants. The major difference of pheromone communication from other molecular communication techniques is the dispersion channel acting under the laws of turbulent diffusion. In this paper, the pheromone channel is modeled as a Gaussian puff, i.e., a cloud of pheromone released instantaneously from the source whose dispersion follows a Gaussian distribution. Numerical results on the performance of the overall end-to-end pheromone channel in terms of normalized gain and delay are provided.
V. G. Soukhovolsky
Full Text Available Features of external environmental factors (such as electromagnetic radiation in certain spectral bands influencing pheromone molecules, which are carriers of information for forest insects in the search of the opposite sex, were examined. Stability of pheromone molecules for external influences has been studied for siberian moth Dendrolimus superans sibiricus Tschetv., pine moth Dendrilimus pini L., gypsy moth Lymantria dispar L., for xylophages Ips typographus L., Monochamus urussovi Fish. and Monochamus galloprovincialis Oliv. Properties of pheromone molecules were evaluated by calculations using quantum-chemical method B3LYP. Existing methods of quantum-chemical calculations are useful for analyzing the properties of quite small and uncomplicated molecules of forest insect pheromones. The calculations showed that the molecules of insect pheromones are able to absorb light in the ultraviolet range and move into an excited state. The values of dipole moments, the wavelengths of the absorption, atomic and molecular electronic properties of pheromones in the ground and excited states were calculated. The calculations showed that for the reaction of pheromones with oxygen an energy barrier is somewhat higher than for reactions of pheromones with water vapor. The worst reaction of pheromones with water molecules likely to pheromones such molecules whose dipole moment is comparable to the dipole moment of water. Quantum-chemical characteristics of the pheromone molecules can be linked to specific behavior of the insects.
Successive extraction of the bark with solvents of increasing polarity yielded about 60% of soluble material. The alcohol and water extracts contained principally simple polyphenols and their glycosides, tannins, mono-and disaccharides, soluble hemicelluloses and pectins. Hot water extracts are suitable for production of adhesives by reaction with formaldehyde, but their polyphenol content is only 50%. The polyphenols and their glycosides, and glucosides of hydroxystilbenes, were investigated in detail.
Iravani, S.; Zolfaghari, B.
Bark extract of Pinus pinaster contains numerous phenolic compounds such as catechins, taxifolin, and phenolic acids. These compounds have received considerable attentions because of their anti-inflammatory, antimutagenic, anticarcinogenic, antimetastatic and high antioxidant activities. Although P. pinaster bark has been intensely investigated in the past; there is comparably less information available in the literature in regard to P. eldarica bark. Therefore, the aim of this study was to determine the chemical composition of P. eldarica commonly found in Iran. A reversed-phase high pressure liquid chromatography (RP-HPLC) method for the determination of catechin, caffeic acid, ferulic acid, and taxifolin in P. pinaster and P. eldarica was developed. A mixture of 0.1% formic acid in deionized water and 0.1% formic acid in acetonitrile was used as the mobile phase, and chromatographic separation was achieved on a Nova pack C18 at 280 nm. The two studied Pinus species contained high amounts of polyphenolic compounds. Among four marker compounds, the main substances identified in P. pinaster and P. eldarica were taxifolin and catechin, respectively. Furthermore, the composition of the bark oil of P. eldarica obtained by hydrodistillation was analyzed by gas chromatography/mass spectroscopy (GC/MS). Thirty-three compounds accounting for 95.1 % of the oil were identified. The oils consisted mainly of mono- and sesquiterpenoid fractions, especially α-pinene (24.6%), caryophyllene oxide (14.0%), δ-3-carene (10.7%), (E)-β-caryophyllene (7.9%), and myrtenal (3.1%). PMID:25657795
In order to analyze the involvement of pheromones in cell recognition and mating in a homothallic fungus, two putative pheromone precursor genes, named ppg1 and ppg2, were isolated from a genomic library of Sordaria macrospora. The ppg1 gene is predicted to encode a precursor pheromone that is processed by a Kex2-like protease to yield a pheromone that is structurally similar to the alpha-factor of the yeast Saccharomyces cerevisiae. The ppg2 gene encodes a 24-amino-acid polypeptide that contains a putative farnesylated and carboxy methylated C-terminal cysteine residue. The sequences of the predicted pheromones display strong structural similarity to those encoded by putative pheromones of heterothallic filamentous ascomycetes. Both genes are expressed during the life cycle of S. macrospora. This is the first description of pheromone precursor genes encoded by a homothallic fungus. Southern-hybridization experiments indicated that ppg1 and ppg2 homologues are also present in other homothallic ascomycetes.
Carreira, Teresa; Lopes, Sandra; Maia, Elisa
The antipyretic properties of cinchona barks were known since ancient times in South America, particularly in Peru. The use of these barks in medicines against “fevers” in Europe in the 17th century made the exploitation of cinchonas of Peru a highly productive process, and those cinchona trees became menaced. The Portuguese government aware of the problem searched an alternative in cinchona varieties existing in Brazil. By the beginning of 19th century, samples of different Brazilian barks w...
Lars Ostlund; Lisa Ahlberg; Olle Zackrisson; Ingela Bergman; Steve Arno
The Sami people of northern Scandinavia and many indigenous peoples of North America have used pine (Pinus spp.) inner bark for food, medicine and other purposes. This study compares bark-peeling and subsequent uses of pine inner bark in Scandinavia and western North America, focusing on traditional practices. Pine inner bark contains substances - mainly carbohydrates...
Milan Pernek; Stefan Wirth; Stacy R. Blomquist; Dimitrios N. Avtzis; John C. Moser
Abstract: The species composition and abundance of phoretic mites of the bark beetle Pityokteines curvidens caught in pheromone traps were investigated in Croatia. The P. curvidens trapping programs have been in an experimental phase in Croatia since 2004 as a possible monitoring and control system. The trapping program also permits the opportunity to sample phoretic...
Ceschi Marco A.
Full Text Available Isoprenylation of aldehydes and ketones was directly performed by selective indium insertion on a mixture of 2-bromomethyl-1,3-butadiene and its vinylic isomers in good yields. A short synthesis of (±-ipsenol, an aggregation pheromone of the Ips paraconfusus bark beetle, demonstrates the utility of this method in organic synthesis.
Zhang, Ya-Nan; Xia, Yi-Han; Zhu, Jia-Yao; Li, Sheng-Yun; Dong, Shuang-Lin
The general pathway of biosynthesis and degradation for Type-I sex pheromones in moths is well established, but some genes involved in this pathway remain to be characterized. The purple stem borer, Sesamia inferens, employs a pheromone blend containing components with three different terminal functional groups (Z11-16:OAc, Z11-16:OH, and Z11-16:Ald) of Type-I sex pheromones. Thus, it provides a good model to study the diversity of genes involved in pheromone biosynthesis and degradation pathways. By analyzing previously obtained transcriptomic data of the sex pheromone glands and antennae, we identified 73 novel genes that are possibly related to pheromone biosynthesis (46 genes) or degradation (27 genes). Gene expression patterns and phylogenetic analysis revealed that one desaturase (SinfDes4), one fatty acid reductase (SinfFAR2), and one fatty acid xtransport protein (SinfFATP1) genes were predominantly expressed in pheromone glands, and clustered with genes involved in pheromone synthesis in other moth species. Ten genes including five carboxylesterases (SinfCXE10, 13, 14, 18, and 20), three aldehyde oxidases (SinfAOX1, 2 and 3), and two alcohol dehydrogenases (SinfAD1 and 3) were expressed specifically or predominantly in antennae, and could be candidate genes involved in pheromone degradation. SinfAD1 and 3 are the first reported alcohol dehydrogenase genes with antennae-biased expression. Based on these results we propose a pathway involving these potential enzyme-encoding gene candidates in sex pheromone biosynthesis and degradation in S. inferens. This study provides robust background information for further elucidation of the genetic basis of sex pheromone biosynthesis and degradation, and ultimately provides potential targets to disrupt sexual communication in S. inferens for control purposes.
Group-living species produce signals that alter the behavior and even the physiology of their social partners. Social insects possess especially sophisticated chemical communication systems that govern every aspect of colony life, including the defining feature of eusociality: reproductive division of labor. Current evidence hints at the central importance of queen pheromones, but progress has been hindered by the fact that such pheromones have only been isolated in honeybees. In a pair of papers on the ant Lasius niger, we identified and investigated a queen pheromone regulating worker sterility. The cuticular hydrocarbon 3-methylhentriacontane (3-MeC(31)) is correlated with queen maturity and fecundity and workers are also more likely to execute surplus queens that have low amounts of this chemical. Experiments with synthetic 3-MeC(31) found that it inhibits ovarian development in queenless workers and lowers worker aggression towards objects coated with it. Production of 3-MeC(31) by queens was depressed by an experimental immune challenge, and the same chemical was abundant on queenlaid eggs, suggesting that the workers' responses to the queen are conditional on her health and fecundity. Together with other studies, these results indicate that queen pheromones are honest signals of quality that simultaneously regulate multiple social behaviors.
Attraction of virgin females to odor of calling males was demonstrated. This sex pheromone mediated attraction occurred during the latter half of a 13-h photophase but not during the first half of the day. Two major components of emissions of calling males, 2,5-dimethylpyrazine (DMP) and 2,5-dihyd...
The study reveals that pre-ovulatory females of the fish Barilius bendelisis (Ham.) release sex steroids and their conjugates into the water and that a steroid sulphate of these compounds functions as a potent sex pheromone which stimulates milt production in conspecific males prior to spawning. Since males exposed to the ...
M.E. Teske; H.W. Thistle; B.L. Strom; H. Zhu
A first principle modeling approach has been applied to available data describing the elution of semiochemicals from pheromone dispensers. These data included field data for 27 products developed by several manufacturers, including homemade devices, as well as environmental chamber data collected on three semiochemical products. The goal of this effort was to...
Bouwer, Marc Clement; Slippers, Bernard; Wingfield, Michael John; Allison, Jeremy Dean; Rohwer, Egmont Richard
The Coryphodema tristis (Drury) is an important pest of Eucalyptus nitens (Deane and Maiden) plantations in South Africa. The gregarious larvae of this pest cause damage by feeding on the tree sapwood, and adults emerge in spring each year. The aim of this study was to optimize pheromone traps for operational use in management programs. This was achieved by investigating different pheromone blend combinations and trap types for efficacy under field conditions. Our results confirm that the cross vane bucket funnel trap baited with a 95:2.5:2.5 volumetric blend of Z9-14:OAc, Z9-14:OH, and 14Ac was superior to similarly baited standard bucket funnel and delta traps. We also estimated the release rate and ratios of the pheromone compounds loaded into an artificial permeation dispenser through solid-phase microextraction sampling. Results showed that the released blend of pheromone compounds mirrored the dispensed ratios relatively accurately and that release rates are affected by temperature. © 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.
Strong selection to secure paternity in polyandrous species leads to the evolution of numerous chemicals in the male's seminal content. These include antiaphrodisiac pheromones, which are transmitted from the male to the female during mating to render her unattractive to subsequent males. An increasing number of species have been shown to use these chemicals. Herein, I examine the taxonomic distribution of species using antiaphrodisiac pheromones, the selection pressures driving their evolution in both males and females, and the ecological interactions in which these pheromones are involved. The literature review shows a highly skewed distribution of antiaphrodisiac use; all species currently known to use them are insects with the exception of the garter snakes Thamnophis sirtalis parietalis and T. radix. Nonetheless, many taxa have not yet been tested for the presence of antiaphrodisiacs, in groups both closely and distantly related to species known to express them. Within the Insecta, there have been multiple cases of convergent evolution of antiaphrodisiac pheromones using different chemical compounds and methods of transmission. Antiaphrodisiacs usually benefit males, but their effect on females is variable as they can either prevent them from mating multiple times or help them reduce male harassment when they are unreceptive. Some indirect costs of antiaphrodisiacs also impact both males and females, but more research is needed to determine how general this pattern is. Additional research is also important to understand how antiaphrodisiacs interact with the reproductive biology and sexual communication in different species. © 2016 Cambridge Philosophical Society.
Harari, Ally R; Zahavi, Tirtza; Thiéry, Denis
A secondary sexual character may act as an honest signal of the quality of the individual if the trait bears a cost and if its expression is phenotypically condition dependent. The cost of increasing the trait should be tolerable for individuals in good condition but not for those in a poor condition. The trait thus provides an honest signal of quality that enables the receiver to choose higher quality mates. Evidence for sex pheromones, which play a major role in shaping sexual evolution, inflicting a signaling cost is scarce. Here, we demonstrate that the amount of the major component of the pheromone in glands of Lobesia botrana (Lepidoptera) females at signaling time was significantly greater in large than in small females, that male moths preferred larger females as mates when responding to volatile signals, and small virgin females, but not large ones, exposed to conspecific pheromone, produced, when mated, significantly fewer eggs than nonexposed females. The latter indicates a condition-dependent cost of signaling. These results are in accordance with the predictions of condition-dependent honest signals. We therefore suggest that female signaling for males using sex pheromones bears a cost and thus calling may serve as honest advertisement for female quality. © 2011 The Author(s). Evolution© 2011 The Society for the Study of Evolution.
Prchalová, Darina; Buček, Aleš; Brabcová, Jana; Žáček, Petr; Kindl, Jiří; Valterová, Irena; Pichová, Iva
Roč. 17, č. 3 (2016), s. 260-267 ISSN 1439-4227 R&D Projects: GA MŠk LO1302; GA ČR GA15-06569S Institutional support: RVO:61388963 Keywords : biosynthesis * Bombus spp. * gene expression * isoprenoid s * pheromones * transcriptional regulation Subject RIV: CE - Biochemistry Impact factor: 2.847, year: 2016
Muenz, Thomas S.; Maisonnasse, Alban; Plettner, Erika; Le Conte, Yves; Rössler, Wolfgang
Social work force distribution in honeybee colonies critically depends on subtle adjustments of an age-related polyethism. Pheromones play a crucial role in adjusting physiological and behavioral maturation of nurse bees to foragers. In addition to primer effects of brood pheromone and queen mandibular pheromone—both were shown to influence onset of foraging—direct worker-worker interactions influence adult behavioral maturation. These interactions were narrowed down to the primer pheromone ethyl oleate, which is present at high concentrations in foragers, almost absent in young bees and was shown to delay the onset of foraging. Based on chemical analyses, physiological recordings from the antenna (electroantennograms) and the antennal lobe (calcium imaging), and behavioral assays (associative conditioning of the proboscis extension response), we present evidence that ethyl oleate is most abundant on the cuticle, received by olfactory receptors on the antenna, processed in glomeruli of the antennal lobe, and learned in olfactory centers of the brain. The results are highly suggestive that the primer pheromone ethyl oleate is transmitted and perceived between individuals via olfaction at close range.
van Zweden, Jelle Stijn
of their ovaries and by preventing other workers from reproducing (worker policing). However, what maintains the honesty of such queen pheromones is still under discussion. The explanation that an honest queen signal evolves simply because it serves the interest of all colony members does not seem to hold, since...
Linnakoski, Riikka; Mahilainen, Saila; Harrington, Alison; Vanhanen, Henri; Eriksson, Miikka; Mehtätalo, Lauri; Pappinen, Ari; Wingfield, Michael J
The ophiostomatoid fungi (Microascales and Ophiostomatales, Ascomycota) are common associates of Ips typographus, and include tree pathogens and species responsible for blue-stain of timber. Fungal assemblages associated with I. typographus have varied considerably between studies but few investigations have attempted to explain this variation. For this reason, we assessed the overall cultivable fungal diversity associated with I. typographus in a storm-felled spruce forest in south-eastern Finland. Fungi were isolated from the individually collected beetles as well as their phoretic mites in spring, summer and autumn, including different life stages of the beetle (hibernation, dispersal flight and first generation). The internal transcribed spacer (ITS) gene region was used to identify the fungi. A total of 32 operational taxonomic units (OTUs) were found and these resided in four fungal phyla/subphyla (24 Ascomycota, 2 Basidiomycota, 5 Mucoromycotina, 1 Mortierellomycotina) in association with adult bark beetles. Ophiostomatoid species were the most commonly detected fungal associates. A generalized linear model analysis showed a clear association between fungal communities and season, indicating seasonal succession among I. typographus-associated fungi. The season of sampling appears to be an important factor that has resulted in inconsistencies between results in previous studies. Many of these fungi were also found on phoretic mites and their presence or absence could have influenced variation in patterns of association.
Chang, J F; Benedict, J H; Payne, T L; Camp, B J; Vinson, S B
An effluvial method was developed to collect the pheromone, grandlure from actively calling male boll weevils,Anthonomus grandis Boheman. The adsorbant, Porapak Q (ethylvinylbenzene-divinylbenzene), was utilized to trap and concentrate the pheromone. Captured pheromone was desorbed from columns packed with Porapak Q by elution withn-pentane and quantified by capillary column gas-liquid chromatography. In recovery studies with known amounts of synthetic grandlure, we found that the amount of each pheromone component collected was a function of collection duration, elution volume, and initial concentration. This effluvial method was capable of recovering as much as 94.9% of a known quantity (80 μg) of grandlure. The chromatograms were free of extraneous peaks. In studies of insect-produced pheromone, the effluvial method was used to collect pheromone from the air space surrounding male boll weevils as they fed on flower buds from CAMD-E cotton. The quantity and quality of boll-weevil-produced pheromone was determined for days 6, 8, 10, 11, 12, 13, and 14 of boll weevil adulthood. The maximum quantity of natural pheromone was produced on day 13 (4.2 μg/weevil) with a pheromone component ratio of 2.41∶2.29∶0.95∶1 for components I, II, III, and IV, respectively. The effluvial method described in this report is an efficient method to collect and quantify boll weevil pheromone from the atmosphere surrounding actively calling insects. Other applications of this method are suggested.
Fotini A Koutroumpa
Full Text Available Pheromone communication relies on highly specific signals sent and received between members of the same species. However, how pheromone specificity is determined in moth olfactory circuits remains unknown. Here we provide the first glimpse into the mechanism that generates this specificity in Ostrinia nubilalis. In Ostrinia nubilalis it was found that a single locus causes strain-specific, diametrically opposed preferences for a 2-component pheromone blend. Previously we found pheromone preference to be correlated with the strain and hybrid-specific relative antennal response to both pheromone components. This led to the current study, in which we detail the underlying mechanism of this differential response, through chemotopically mapping of the pheromone detection circuit in the antenna. We determined that both strains and their hybrids have swapped the neuronal identity of the pheromone-sensitive neurons co-housed within a single sensillum. Furthermore, neurons that mediate behavioral antagonism surprisingly co-express up to five pheromone receptors, mirroring the concordantly broad tuning to heterospecific pheromones. This appears as possible evolutionary adaptation that could prevent cross attraction to a range of heterospecific signals, while keeping the pheromone detection system to its simplest tripartite setup.
Full Text Available Lepidopteran insects use sex pheromones for sexual communication. Pheromone receptors expressed on peripheral olfactory receptor neurons (ORNs are critical part to detect the sex pheromones. In genus Ostrinia, several pheromone receptors were functional analyzed in O. nubilalis and O. scapulalis but the knowledge in O. furnacalis was rare. In this study, seven pheromone receptors were deorphanized by heterologous expression system of Xenopus oocytes. Functional types of sensilla trichoidea were classified by single sensillum recordings to interpret the response pattern of olfactory sensory neurons to Ostrinia pheromone components. OfurOR4 and OfurOR6 responded to the major sex pheromone Z/E12-14:OAc. OfurOR4 is the main receptor for both Z/E12-14:OAc and OfurOR6 mainly responded to E12-14:OAc. Functional differentiation of gene duplication were found between OfurOR5a and OfurOR5b. OfurOR5b showed a broad response to most of the pheromone components in O. furnacalis, whereas OfurOR5a was found without ligands. OfurOR7 showed a specific response to Z9-14:OAc and OfurOR8 mainly responded to Z11-14:OAc and E11-14:OAc. OfurOR3 did not respond to any pheromone components. Our results improved the current knowledge of pheromone reception in Ostrinia species which may contribute to speciation.
Seibel, Christian; Tisch, Doris; Kubicek, Christian P.; Schmoll, Monika
Discovery of sexual development in the ascomycete Trichoderma reesei (Hypocrea jecorina) as well as detection of a novel class of peptide pheromone precursors in this fungus indicates promising insights into its physiology and lifestyle. Here we investigated the role of the two pheromone receptors HPR1 and HPR2 in the H. jecorina pheromone-system. We found that these pheromone receptors show an unexpectedly high genetic variability among H. jecorina strains. HPR1 and HPR2 confer female fertility in their cognate mating types (MAT1-1 or MAT1-2, respectively) and mediate induction of fruiting body development. One compatible pheromone precursor–pheromone receptor pair (hpr1–hpp1 or hpr2–ppg1) in mating partners was sufficient for sexual development. Additionally, pheromone receptors were essential for ascospore development, hence indicating their involvement in post-fertilisation events. Neither pheromone precursor genes nor pheromone receptor genes of H. jecorina were transcribed in a strictly mating type dependent manner, but showed enhanced expression levels in the cognate mating type. In the presence of a mating partner under conditions favoring sexual development, transcript levels of pheromone precursors were significantly increased, while those of pheromone receptor genes do not show this trend. In the female sterile T. reesei strain QM6a, transcriptional responses of pheromone precursor and pheromone receptor genes to a mating partner were clearly altered compared to the female fertile wild-type strain CBS999.97. Consequently, a delayed and inappropriate response to the mating partner may be one aspect causing female sterility in QM6a. PMID:22884620
Full Text Available Sustaining biodiversity as well as taking advantage of the natural environment’s resistance are the key elements which should be considered when designing integrated plans for the protection of hazelnut groves. An effort has been made in this study to analyse the impact of different soil cultivation methods in hazelnut groves, on the species composition and number of individuals in carabid assemblages (Coleoptera: Carabidae. Another aim was to determine which method of inter-row soil management had the least negative effect on assemblages of these beetles. Because of the type of habitat, the xerothermic species characteristic for southeastern Europe, i.e. Calathus ambiguus, Poecilus lepidus, Harpalus calceatus, and H. griseus, were the most numerous. The qualitative and quantitative analysis of the captured individuals implied that the optimal soil tillage system in young hazelnut groves is when soil is kept fallow with machines or chemicals, or when soil is covered with manure. The least favourable practice for the appearance of ground beetles of the Carabidae family is the use of polypropylene fabric, bark or sawdust, to cover soil
Camiletti, Alison L.; Awde, David N.; Thompson, Graham J.
In this study we test one central prediction from sociogenomic theory—that social and non-social taxa share common genetic toolkits that regulate reproduction in response to environmental cues. We exposed Drosophila females of rover ( for R) and sitter ( for s) genotypes to an ovary-suppressing pheromone derived from the honeybee Apis mellifera. Surprisingly, queen mandibular pheromone (QMP) affected several measures of fitness in flies, and in a manner comparable to the pheromone's normal effect on bee workers. QMP-treated sitter flies had smaller ovaries that contained fewer eggs than did untreated controls. QMP-treated rover flies, by contrast, showed a more variable pattern that only sometimes resulted in ovary inhibition, while a third strain of fly that contains a sitter mutant allele in a rover background ( for s2) showed no ovarian response to QMP. Taken together, our results suggest that distinctly non-social insects have some capacity to respond to social cues, but that this response varies with fly genotype. In general, the interspecific response is consistent with a conserved gene set affecting reproductive physiology. The differential response among strains in particular suggests that for is itself important for modulating the fly's pheromonal response.
Weng, Chen; Fu, Yuxia; Jiang, Hongtao; Zhuang, Shulin; Li, Hongliang
The honeybee's social behavior is closely related to the critical response to pheromone, while pheromone binding proteins (PBPs) play an important role in binding and transferring those pheromones. Here we report one known PBP, antennal special protein 1(ASP1), which has high affinity with a queen mandibular pheromone component, methyl-p-hydroxybenzoate (HOB). In this study, multiple fluorescent spectra, UV absorption spectra, circular dichroism (CD) spectra and molecular docking analysis were combined to clarify the binding process. Basically, fluorescence intensity of ASP1 could be considerably quenched by HOB with an appropriate interaction distance (3.1 nm), indicating that a complex, which is more stable in lower temperature, was formed. The fact ΔH < 0, ΔS < 0, by thermodynamic analysis, indicated the van der Waals and hydrogen bond as main driving force. Moreover, synchronous fluorescence spectra and CD spectra analysis showed the change of partial hydrophilicity of ASP1 and the increase of α-helix after HOB addition. In conclusion, ASP1 can strongly and spontaneously interact with HOB. But the binding ability decreases with the rise of temperature, which may be necessary for sufficient social stability of hives. This study provides elucidation of the detailed binding mechanism and potential physicochemical basis of thermal stability to the social behavior of honeybee. Copyright © 2014 Elsevier B.V. All rights reserved.
Purpose: To evaluate the effect of a topical application of a cream formulation containing extract of. Acacia nilotica bark extract on human cheek skin texture. Methods: A cream containing 3 % concentrated extract of Acacia nilotica bark was developed by entrapping the extract in the internal aqueous phase of the cream ...
Comparative analysis of the larvicidal properties of aqueous extracts of leaves, bark and nutshell of Anacardium occidentale L. (Cashew) were evaluated on the larvae of Anopheles gambiae. Three concentrations of 10/100ml, 20/100ml and 30/100ml each of leaf, bark and nutshell were prepared in three replicates.
While quarter strength (5 g/ml) concentrations of the bark methanol and ethanol extracts were the MICs against Staphylococcus aureus and Micrococcus luteus. The phytochemical analysis carried out on B. ferruginea leaves and bark detected the presence of alkaloids, flavonoids, tannin, cardiac glycosides, anthraquinone, ...
Tree diameter under and over bark at breast height (dbh), wood density and bark thickness were assessed on samples from control-pollinated families of Eucalyptus grandis, E. urophylla, E. grandis × E. urophylla and E. urophylla × E. grandis. The material was planted in field trials in the coastal Zululand region of South ...
Svensson, Glenn P; Ryne, Camilla; Löfstedt, Christer
The short-term evolutionary effect of pheromone-based mating disruption on the mating ability of the Indian meal moth, Plodia interpunctella, was investigated. Three independent selection lines were established, and the mating ability of moths in plastic tents treated with high doses of pheromone and in control tents was compared for two consecutive generations. In addition, the heritability of the sex pheromone blend, measured as the ratio of two major pheromone components (Z,E)-9,12-tetradecadienyl acetate and (Z,E)-9,12-tetradecadienol, was estimated. Based on a mother-daughter regression analysis including 21 families, the heritability of the pheromone blend was 0.65 +/- 0.14, indicating a potential for evolutionary change of the character. However, no increase in mating ability of females in pheromone-treated tents or alteration of the pheromone blend was observed in any selection line when compared with control lines, indicating no or weak selection on the pheromone blend as well as other traits influencing mating ability of this species under the created mating disruption conditions. Factors contributing to the lack of selection effects are discussed.
Singh, Meenakshi; Khatoon, Sayyada; Singh, Shweta; Kumar, Vivek; Rawat, Ajay Kumar Singh; Mehrotra, Shanta
The stem barks are the rich sources of tannins and other phenolic compounds. Tannins inhibited the growth of various fungi, yeast, bacteria and virus. Hence, ten stem barks of ethnomedicinally important plants were screened for antibacterial and antifungal activities against human pathogenic strains. Air-dried and powdered stem bark of each plant was extracted with 50% aqueous ethanol, lyophilized and the dried crude extracts were used for the screening against 11 bacteria and 8 fungi. Antibacterial and antifungal activities were performed according to microdilution methods by NCCLS. The plants Prosopis chilensis, Pithecellobium dulce, Mangifera indica showed significant antibacterial and antifungal activities against Streptococcus pneumonia, Enterobacter aerogenes, Klebsiella pneumonia and Candida albicans with MIC of 0.08mg/ml. Pithecellobium dulce bark also showed significant antibacterial activity against Bacillus cereus. The bark of Pithecellobium dulce has more or less similar activity against the known antibiotic and may be considered as potent antimicrobial agent for various infectious diseases.
West, Daniel R; Briggs, Jennifer S; Jacobi, William R; Negrón, José F
Recent evidence of range expansion and host transition by mountain pine beetle (Dendroctonus ponderosae Hopkins; MPB) has suggested that MPB may not primarily breed in their natal host, but will switch hosts to an alternate tree species. As MPB populations expanded in lodgepole pine forests in the southern Rocky Mountains, we investigated the potential for movement into adjacent ponderosa pine forests. We conducted field and laboratory experiments to evaluate four aspects of MPB population dynamics and host selection behavior in the two hosts: emergence timing, sex ratios, host choice, and reproductive success. We found that peak MPB emergence from both hosts occurred simultaneously between late July and early August, and the sex ratio of emerging beetles did not differ between hosts. In two direct tests of MPB host selection, we identified a strong preference by MPB for ponderosa versus lodgepole pine. At field sites, we captured naturally emerging beetles from both natal hosts in choice arenas containing logs of both species. In the laboratory, we offered sections of bark and phloem from both species to individual insects in bioassays. In both tests, insects infested ponderosa over lodgepole pine at a ratio of almost 2:1, regardless of natal host species. Reproductive success (offspring/female) was similar in colonized logs of both hosts. Overall, our findings suggest that MPB may exhibit equally high rates of infestation and fecundity in an alternate host under favorable conditions. © 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.
Berryman, E.; Frank, J. M.; Speckman, H. N.; Bradford, J. B.; Ryan, M. G.; Massman, W. J.; Hawbaker, T. J.
Bark beetle outbreaks in Western North American forests are often considered a high-severity disturbance from a carbon (C) cycling perspective, but field measurements that quantify impacts on C dynamics are very limited. Often, factors out of the researcher's control complicate the separation of beetle impacts from other drivers of C cycling variability and restrict statistical inference. Fortuitously, we had four years of pre-spruce beetle outbreak C cycle measurements in a subalpine forest in southeastern Wyoming (Glacier Lakes Ecosystem Experiments Site, or GLEES) and sustained intermittent monitoring for nearly a decade after the outbreak. Here, we synthesize published and unpublished pre- and post-outbreak measurements of key C cycle stocks and fluxes at GLEES. Multiple lines of evidence, including chamber measurements, eddy covariance measurements, and tracking of soil and forest floor C pools over time, point to the GLEES outbreak as a moderate-severity disturbance for C loss to the atmosphere, despite 70% to 80% of overstory tree death. Reductions in NEE were short-lived and the forest quickly returned to a carbon-neutral state, likely driven by an uptick in understory growth. Effect of mortality on the C cycle was asymmetrical, with a 50% reduction in net carbon uptake (NEE) two years into the outbreak, yet no measureable change in either ecosystem or growing season soil respiration. A small pulse in soil respiration occurred but was only detectable during the winter and amounted to < 10% of NEE. Possible reasons for the lack of measureable respiration response are discussed with emphasis on lessons learned for monitoring and modeling future outbreaks. We suggest a comprehensive assessment and definition of "moderate-severity" disturbances for Western forests and suggest that all tree mortality events may not be high-severity when it comes to C fluxes.
Mary E. Mason; Marek Krasowski; Judy Loo; Jennifer. Koch
Proteomic analysis of beech bark proteins from trees resistant and susceptible to beech bark disease (BBD) was conducted. Sixteen trees from eight geographically isolated stands, 10 resistant (healthy) and 6 susceptible (diseased/infested) trees, were studied. The genetic complexity of the sample unit, the sampling across a wide geographic area, and the complexity of...
Urban foresters routinely emphasise the importance of taxonomic diversity to reduce the vulnerability of tree assemblages to invasive pests, but it is unclear to what extent diversity reduces vulnerability to polyphagous (i.e. generalist) pests. Drawing on field data from seven communities in metropolitan Cincinnati, Ohio, USA, we tested the hypothesis that communities with higher diversity would exhibit lower vulnerability to the polyphagous Asian longhorned beetle, which currently threatens the region. Based on street tree compositions and the beetle?s host preferences, Asian longhorned beetle threatened up to 35.6% of individual street trees and 47.5% of the total basal area across the study area, but we did not see clear connections between taxonomic diversity and beetle vulnerability among study communities. For example, the city of Fairfield was among the least diverse communities but had the lowest proportion of trees vulnerable to Asian longhorned beetle, whereas the city of Wyoming exhibited high diversity and high vulnerability. On the other hand, Forest Park aligned with our original hypothesis, as it was characterised by low diversity and high vulnerability. Our results demonstrate that relatively high taxonomic diversity in street tree assemblages does not necessarily lead to reduced vulnerability to a polyphagous pest. Considering the threats posed by polyphagous pests, selecting a set of relatively pest resistant trees known to perform well in urb
E Reed, David; Ewers, Brent E; Pendall, Elise
Quantifying impacts of ecological disturbance on ecosystem carbon and water fluxes will improve predictive understanding of biosphere—atmosphere feedbacks. Tree mortality caused by mountain pine bark beetles (Dendroctonus ponderosae) is hypothesized to decrease photosynthesis and water flux to the atmosphere while increasing respiration at a rate proportional to mortality. This work uses data from an eddy-covariance flux tower in a bark beetle infested lodgepole pine (Pinus contorta) forest to test ecosystem responses during the outbreak. Analyses were conducted on components of carbon (C) and water fluxes in response to disturbance and environmental factors (solar radiation, soil water content and vapor pressure deficit). Maximum CO 2 uptake did not change as tree basal area mortality increased from 30 to 78% over three years of beetle disturbance. Growing season evapotranspiration varied among years while ecosystem water use efficiency (the ratio of net CO 2 uptake to water vapor loss) did not change. Between 2009 and 2011, canopy water conductance increased from 98.6 to 151.7 mmol H 2 O m −2 s −1 . Ecosystem light use efficiency of photosynthesis increased, with quantum yield increasing by 16% during the outbreak as light increased below the mature tree canopy and illuminated remaining vegetation more. Overall net ecosystem productivity was correlated with water flux and hence water availability. Average weekly ecosystem respiration, derived from light response curves and standard Ameriflux protocols for CO 2 flux partitioning into respiration and gross ecosystem productivity, did not change as mortality increased. Separate effects of increased respiration and photosynthesis efficiency largely canceled one another out, presumably due to increased diffuse light in the canopy and soil organic matter decomposition resulting in no change in net CO 2 exchange. These results agree with an emerging consensus in the literature demonstrating CO 2 and H 2 O dynamics
In virtually every forest habitat, ambrosia beetles (Coleoptera: Curculionidae: Scolytinae, Platypodinae) plant and maintain symbiotic fungus gardens inside dead or dying wood. Some introduced ambrosia beetles aggressively attack live trees and can damage tree crops, lumber, and native woody plant t...
Protopopova, Alexandra; Kisten, Dmitri; Wynne, Clive
The aim of this study was to develop a humane alternative to the traditional remote devices that deliver punishers contingent on home-alone dog barking. Specifically, we evaluated the use of remote delivery of food contingent on intervals of not barking during the pet owner's absence. In Experiment 1, 5 dogs with a history of home-alone nuisance barking were recruited. Using an ABAB reversal design, we demonstrated that contingent remote delivery of food decreased home-alone barking for 3 of the dogs. In Experiment 2, we demonstrated that it is possible to thin the differential-reinforcement-of-other-behavior (DRO) schedule gradually, resulting in a potentially more acceptable treatment. Our results benefit the dog training community by providing a humane tool to combat nuisance barking. © 2016 Society for the Experimental Analysis of Behavior.
Vogt, R G; Riddiford, L M; Prestwich, G D
Behavioral and electrophysiological evidence has suggested that sex pheromone is rapidly inactivated within the sensory hairs soon after initiation of the action-potential spike. We report the isolation and characterization of a sex-pheromone-degrading enzyme from the sensory hairs of the silkmoth Antheraea polyphemus. In the presence of this enzyme at physiological concentration, the pheromone [(6E,11Z)-hexadecadienyl acetate] has an estimated half-life of 15 msec. Our findings suggest a mol...
Thomas L. Eberhardt
Bark thicknesses for longleaf pine (Pinus palustris Mill.) were investigated using disks collected from trees harvested on a 70-year-old plantation. Maximum inner bark thickness was relatively constant along the tree bole whereas maximum outer bark thickness showed a definite decrease from the base of the tree to the top. The minimum whole bark thickness followed the...
STEBBING P. D.
Full Text Available The need for an effective method of controlling invasive species of crayfish is of utmost importance given the plight of Europe’s native crayfish species. Many techniques have been applied to the growing problem with little success. Pheromones have been used to control terrestrial insect pests for a number of years with many success stories. The concept of applying pheromone control methods to the aquatic environment is by no means new, but has not been previously developed. This paper discusses the preliminary results from field trials testing traps baited with Pacifastacus leniusculus pheromones, and the potential application of the pheromones in controlling P. leniusculus populations.
Opioid Addiction; Opioid Abuse, Continuous Use; Opioid Use; Opioid-Related Disorders; Paternal Pheromone Deficiency; Opioid Dependence; Opioid Abuse; Opioid-use Disorder; Opioid Intoxication; Opioid Abuse, Episodic
Wharam, Barney; Weldon, Laura; Viney, Mark
Animals use information from their environment to make decisions, ultimately to maximize their fitness. The nematode C. elegans has a pheromone signalling system, which hitherto has principally been thought to be used by worms in deciding whether or not to arrest their development as larvae. Recent studies have suggested that this pheromone can have other roles in the C. elegans life cycle. Here we demonstrate a new role for the C. elegans pheromone, showing that it accelerates hermaphrodites' reproductive rate, a phenomenon which we call pheromone-dependent reproductive plasticity (PDRP). We also find that pheromone accelerates larval growth rates, but this depends on a live bacterial food source, while PDRP does not. Different C. elegans strains all show PDRP, though the magnitude of these effects differ among the strains, which is analogous to the diversity of arrested larval phenotypes that this pheromone also induces. Using a selection experiment we also show that selection for PDRP or for larval arrest affects both the target and the non-target trait, suggesting that there is cross-talk between these two pheromone-dependent traits. Together, these results show that C. elegans' pheromone is a signal that acts at two key life cycle points, controlling alternative larval fates and affecting adult hermaphrodites' reproduction. More broadly, these results suggest that to properly understand and interpret the biology of pheromone signalling in C. elegans and other nematodes, the life-history biology of these organisms in their natural environment needs to be considered.
Full Text Available Male moths can accurately perceive the sex pheromone emitted from conspecific females by their highly accurate and specific olfactory sensory system. Pheromone receptors are of special importance in moth pheromone reception because of their central role in chemosensory signal transduction processes that occur in olfactory receptor neurons in the male antennae. There are a number of pheromone receptor genes have been cloned, however, only a few have been functionally characterized. Here we cloned six full-length pheromone receptor genes from Helicoverpa armigera male antennae. Real-time PCR showing all genes exhibited male-biased expression in adult antennae. Functional analyses of the six pheromone receptor genes were then conducted in the heterologous expression system of Xenopus oocytes. HarmOR13 was found to be a specific receptor for the major sex pheromone component Z11-16:Ald. HarmOR6 was equally tuned to both of Z9-16: Ald and Z9-14: Ald. HarmOR16 was sensitively tuned to Z11-16: OH. HarmOR11, HarmOR14 and HarmOR15 failed to respond to the tested candidate pheromone compounds. Our experiments elucidated the functions of some pheromone receptor genes of H. armigera. These advances may provide remarkable evidence for intraspecific mating choice and speciation extension in moths at molecular level.
Pikielny, Claudio W
Hydrocarbon pheromones on the cuticle of Drosophila melanogaster modulate the complex courtship behavior of males. Recently, three members of the degenerin/epithelial Na+ channel (DEG/ENaC) family of sodium channel subunits, Ppk25, Ppk23, and Ppk29 (also known as Nope), have been shown to function in gustatory perception of courtship-modulating contact pheromones. All three proteins are required for the activation of male courtship by female pheromones. Specific interactions between two of them have been demonstrated in cultured cells, suggesting that, in a subset of cells where they are coexpressed, these three subunits function within a common heterotrimeric DEG/ENaC channel. Such a DEG/ENaC channel may be gated by pheromones, either directly or indirectly, or alternatively may control the excitability of pheromone-sensing cells. In addition, these studies identify taste neurons that respond specifically to courtship-modulating pheromones and mediate their effects on male behavior. Two types of pheromone-sensing taste neurons, F and M cells, have been defined on the basis of their specific response to either female or male pheromones. These reports set the stage for the dissection of the molecular and cellular mechanisms that mediate gustatory detection of contact pheromones.
François J. Verheggen
Full Text Available The Colorado potato beetle (CPB has been a major insect pest to potato farming for over 150 years and various control methods have been established to reduce its impact on potato fields. Crop rotation and pesticide use are currently the most widely used approaches, although alternative methods are being developed. Here we review the role of various volatile and nonvolatile chemicals involved in behavior changes of CPB that may have potential for their control. First, we describe all volatile and nonvolatile chemicals involved in host plant localization and acceptance by CPB beetles, including glycoalcaloids and host plant volatiles used as kairomones. In the second section, we present the chemical signals used by CPB in intraspecific communication, including sex and aggregation pheromones. Some of these chemicals are used by natural enemies of CPBs to locate their prey and are presented in the third section. The last section of this review is devoted a discussion of the potential of some natural chemicals in biological control of CPB and to approaches that already reached efficient field applications.
Jaime A. TEIXEIRA DA SILVA
Full Text Available Durian (Durio zibethinus L. fruit form on the bark of branches. The aim of our research was to assess whether branches bearing different number of fruits have different nutrient contents in their bark. We determined the nitrogen (N, phosphorous (P, potassium (K, and carbon (C content in branch bark 30 days after fruit set using branches bearing different number of fruits per panicle (0, 1, 2 or >2 of two varieties (‘Otong’ and ‘Kani’. Bark was cut into 0.03 m long and 0.005 m wide segments with an average thickness of 0.00085 m. The bark of branches bearing a different number of fruits had the same N, P, K, and C content but different ratios of C/N, C/P, C/K, N/K, and P/K. The bark of ‘Otong’ branches had a higher N content but a lower C/N ratio than ‘Kani’ bark.
The use of bark (mainly Scots pine) as an organic fertilizer and for soil amelioration is explored. A typical analysis of three month old bark is given and methods for composting with solid fertilizers and slurry described. Stacks 3m long by 1m wide and up to 2m height are used with fertilizer (NPK at 2:1.2:1.2 kg/cubic m of bark) added between layers of bark approximately 25 cm deep. Poultry manure or cow/horse/pig manure can be used at up to 10% to 30% respectively of compost volume, and the amount of N fertilizer reduced by up to three quarters depending on the type and quantity of manure. Stacks are turned 2-3 times and used after twelve months. Liquid slurry is best applied to larger stacks every 2-3 days for one month, and then left for 2 and a half to 3 months. Composted bark can be used in young plantations - especially on degraded sites - at rates in the region of 400-800 cubic m/ha, depending on soil type etc. Bark can also be used without composting on some sites, but is best ground first and should be weathered to oxidize the tannins. Composted bark is also used as a mulch on field scale vegetables, generally at 200-400 cubic m/ha.
Laboratory and Field Evaluation of the Entomopathogenic Fungus Beauveria bassiana (Deuteromycotina: Hyphomycetes) for Population Management of Spruce Beetle, Dendroctonus rufipennis (Coleoptera: Scolytinae), in Felled Trees and Factors Limiting Pathogen Success.
Davis, Thomas Seth; Mann, Andrew J; Malesky, Danielle; Jankowski, Egan; Bradley, Clifford
An isolate of the entomopathogenic fungus Beauveria bassiana (Bals.) Vuill. (Deuteromycotina: Hyphomycetes) was tested for its ability to reduce survival and reproduction of spruce beetle, Dendroctonus rufipennis (Kirby) (Coleoptera: Scolytinae), under laboratory and field conditions. Conidial suspension applied directly to adults or to filter papers that adults contacted had a median survival time of 3-4 d in laboratory assays and beetles died more rapidly when exposed to conidial suspension than when treated with surfactant solution only. In the field, conidial suspension was applied to the surface of felled and pheromone-baited Engelmann spruce (Picea engelmannii) trees using a backpack sprayer. Mortality of colonizing parent beetles (F0), reproduction (abundance of F1 offspring in logs), and emergence of F1 beetles from logs was compared between treated and nontreated logs. Application of spore suspension increased mortality of F0 adults by 36% on average. Total F1 reproduction was reduced by 17% and emergence from logs was reduced by 13% in treated logs, but considerable variability in reproduction and emergence was observed. Viable spores were re-isolated from treated logs up to 90 d after application, indicating that spores are capable of long-term persistence on the tree bole microhabitat. Subsequent in vitro tests revealed that temperatures below 15°C and exposure to spruce monoterpenes likely limit performance of B. bassiana under field conditions, but exposure to low-intensity light or interactions with spruce beetle symbiotic fungi were not strongly inhibitory. It is concluded that matching environmental tolerances of biocontrol fungi to field conditions can likely improve their usefulness for control of spruce beetle in windthrown trees.
Granero, Angeles Mena; Sanz, José M. Guerra; Gonzalez, Francisco J. Egea; Vidal, José L. Martinez; Dornhaus, Anna; Ghani, Junaid; Serrano, Ana Roldán; Chittka, Lars
When the frenzied and irregular food-recruitment dances of bumblebees were first discovered, it was thought that they might represent an evolutionary prototype to the honeybee waggle dance. It later emerged that the primary function of the bumblebee dance was the distribution of an alerting pheromone. Here, we identify the chemical compounds of the bumblebee recruitment pheromone and their behaviour effects. The presence of two monoterpenes and one sesquiterpene (eucalyptol, ocimene and farnesol) in the nest airspace and in the tergal glands increases strongly during foraging. Of these, eucalyptol has the strongest recruitment effect when a bee nest is experimentally exposed to it. Since honeybees use terpenes for marking food sources rather than recruiting foragers inside the nest, this suggests independent evolutionary roots of food recruitment in these two groups of bees.
G. M. Nahibasheva; Sh. M. Imanaliev
The article is devoted to studying of ground-beetles fauna of Nukatlinskiy watershed of Republic Dagestan. For the first time the specific structure of ground-beetles this area, the numbering 109 kinds concerning 31 sort is resulted. The analysis of sexual structure of populations and seasonal dynamics of activity ground-beetles is lead.
Secretion of cephalic labial gland of Buff-tailed bumblebee males (Bombus terrestris) contains a mixture of terpene alcohols, aliphatic alcohols, esters and alkanes with small amount of aldehydes potentially biosynthetized of (S)-2,3-dihydrofarnesol and geranylcitronellol (major alcoholic compounds). This secretion acts as a marking and luring pheromone during patrolling. This study is focused on oxidation of terpene alcohols using enzymes of cephalic labial gland of a bumblebee. In vitro inc...
Fortes-Marco, Lluis; Lanuza, Enrique; Martinez-Garcia, Fernando
Some chemicals elicit innate emotionally laden behavioral responses. Pheromones mediate sexual attraction, parental care or agonistic confrontation, whereas predators' kairomones elicit defensive behaviors in their preys. This essay explores the hypothesis that the detection of these semiochemicals relies on highly specific olfactory and/or vomeronasal receptors. The V1R, V2R, and formyl-peptide vomeronasal receptors bind their ligands in highly specific and sensitive way, thus being good candidates for pheromone- or kairomone-detectors (e.g., secreted and excreted proteins, peptides and lipophilic volatiles). The olfactory epithelium also expresses specific receptors, for example trace amine-associated receptors (TAAR) and guanylyl cyclase receptors (GC-D and other types), some of which bind kairomones and putative pheromones. However, most of the olfactory neurons express canonical olfactory receptors (ORs) that bind many ligands with different affinity, being not suitable for mediating responses to pheromones and kairomones. In this respect, trimethylthiazoline (TMT) is considered a fox-derived kairomone for mice and rats, but it seems to be detected by canonical ORs. Therefore, we have reassessed the kairomonal nature of TMT by analyzing the behavioral responses of outbred (CD1) and inbred mice (C57BL/J6) to TMT. Our results confirm that both mouse strains avoid TMT, which increases immobility in C57BL/J6, but not CD1 mice. However, mice of both strains sniff at TMT throughout the test and show no trace of TMT-induced contextual conditioning (immobility or avoidance). This suggests that TMT is not a kairomone but, similar to a loud noise, in high concentrations it induces aversion and stress as unspecific responses to a strong olfactory stimulation. Copyright © 2013 Wiley Periodicals, Inc.
Dosage response mortality of Japanese beetle, masked chafer, and June beetle (Coleoptera: Scarabaeidae) adults when exposed to experimental and commercially available granules containing Metarhizium brunneum
Adult beetles of three different white grub species, Japanese beetle, Popillia japonica, June beetle, Phyllophaga spp., and masked chafer, Cyclocephala spp. were exposed to experimental and commercially available granules containing Metarhizium brunneum (Petch) strain F52, to determine susceptibilit...
Hatano, Eduardo; Kunert, Grit; Bartram, Stefan; Boland, Wilhelm; Gershenzon, Jonathan; Weisser, Wolfgang W
When aphids are attacked by natural enemies, they emit alarm pheromone to alert conspecifics. For most aphids tested, (E)-beta-farnesene (EBF) is the main, or only, constituent of the alarm pheromone. In response to alarm pheromone, alerted aphids drop off the plant, walk away, or attempt to elude predators. However, under natural conditions, EBF concentration might be low due to the low amounts emitted, to rapid air movement, or to oxidative degradation. To ensure that conspecifics are warned, aphids might conceivably amplify the alarm signal by emitting EBF in response to EBF emitted by other aphids. To examine whether such amplification occurs, we synthesized deuterated EBF (DEBF), which allowed us to differentiate between applied and aphid-derived chemical. Colonies of Acyrthosiphon pisum were treated with DEBF, and headspace volatiles were collected and analyzed for evidence of aphid-derived EBF. No aphid-derived EBF was detected, suggesting that amplification of the alarm signal does not occur. We discuss the disadvantages of alarm signal reinforcement.
Full Text Available Biosynthetic infochemical communication is an emerging scientific field employing molecular compounds for information transmission, labelling, and biochemical interfacing; having potential application in diverse areas ranging from pest management to group coordination of swarming robots. Our communication system comprises a chemoemitter module that encodes information by producing volatile pheromone components and a chemoreceiver module that decodes the transmitted ratiometric information via polymer-coated piezoelectric Surface Acoustic Wave Resonator (SAWR sensors. The inspiration for such a system is based on the pheromone-based communication between insects. Ten features are extracted from the SAWR sensor response and analysed using multi-variate classification techniques, i.e., Linear Discriminant Analysis (LDA, Probabilistic Neural Network (PNN, and Multilayer Perception Neural Network (MLPNN methods, and an optimal feature subset is identified. A combination of steady state and transient features of the sensor signals showed superior performances with LDA and MLPNN. Although MLPNN gave excellent results reaching 100% recognition rate at 400 s, over all time stations PNN gave the best performance based on an expanded data-set with adjacent neighbours. In this case, 100% of the pheromone mixtures were successfully identified just 200 s after they were first injected into the wind tunnel. We believe that this approach can be used for future chemical communication employing simple mixtures of airborne molecules.
Li, Jianjun; Wang, Zhengwei; Tan, Ken; Qu, Yufeng; Nieh, James C
Social pollinators such as honey bees face attacks from predators not only at the nest, but also during foraging. Pollinating honey bees can therefore release alarm pheromones that deter conspecifics from visiting dangerous inflorescences. However, the effect of alarm pheromone and its chemical components upon bee avoidance of dangerous food sources remains unclear. We tested the responses of giant honey bee foragers, Apis dorsata, presented with alarm pheromone at a floral array. Foragers investigated the inflorescence with natural alarm pheromone, but 3.3-fold more foragers preferred to land on the 'safe' inflorescence without alarm pheromone. Using gas chromatography-mass spectrometry analysis, we identified eight chemical components in the alarm pheromone, of which three components (1-octanol, decanal and gamma-octanoic lactone) have not previously been reported in this species. We bioassayed six major compounds and found that a synthetic mixture of these compounds elicited behaviors statistically indistinguishable from responses to natural alarm pheromone. By testing each compound separately, we show that gamma-octanoic lactone, isopentyl acetate and (E)-2-decen-1-yl acetate are active compounds that elicit significant alarm responses. Gamma-octanoic lactone elicited the strongest response to a single compound and has not been previously reported in honey bee alarm pheromone. Isopentyl acetate is widely found in the alarm pheromones of sympatric Asian honey bee species, and thus alarmed A. dorsata foragers may produce information useful for conspecifics and heterospecifics, thereby broadening the effects of alarm information on plant pollination. © 2014. Published by The Company of Biologists Ltd.
Sakurai, Takeshi; Mitsuno, Hidefumi; Haupt, Stephan Shuichi; Uchino, Keiro; Yokohari, Fumio; Nishioka, Takaaki; Kobayashi, Isao; Sezutsu, Hideki; Tamura, Toshiki; Kanzaki, Ryohei
In insects and other animals, intraspecific communication between individuals of the opposite sex is mediated in part by chemical signals called sex pheromones. In most moth species, male moths rely heavily on species-specific sex pheromones emitted by female moths to identify and orient towards an appropriate mating partner among a large number of sympatric insect species. The silkmoth, Bombyx mori, utilizes the simplest possible pheromone system, in which a single pheromone component, (E, Z...
Kozina, A; Lemic, D; Bazok, R; Mikac, K M; Mclean, C M; Ivezić, M; Igrc Barčić, J
It is assumed that the abundance of Agriotes wireworms (Coleoptera: Elateridae) is affected by agro-ecological factors such as climatic and edaphic factors and the crop/previous crop grown at the sites investigated. The aim of this study, conducted in three different geographic counties in Croatia from 2007 to 2009, was to determine the factors that influence the abundance of adult click beetle of the species Agriotes brevis Cand., Agriotes lineatus (L.), Agriotes obscurus (L.), Agriotes sputator (L.), and Agriotes ustulatus Schall. The mean annual air temperature, total rainfall, percentage of coarse and fine sand, coarse and fine silt and clay, the soil pH, and humus were investigated as potential factors that may influence abundance. Adult click beetle emergence was monitored using sex pheromone traps (YATLORf and VARb3). Exploratory data analysis was preformed via regression tree models and regional differences in Agriotes species' abundance were predicted based on the agro-ecological factors measured. It was found that the best overall predictor of A. brevis abundance was the previous crop grown. Conversely, the best predictor of A. lineatus abundance was the current crop being grown and the percentage of humus. The best predictor of A. obscurus abundance was soil pH in KCl. The best predictor of A. sputator abundance was rainfall. Finally, the best predictors of A. ustulatus abundance were soil pH in KCl and humus. These results may be useful in regional pest control programs or for predicting future outbreaks of these species. © The Author 2015. Published by Oxford University Press on behalf of the Entomological Society of America.
Full Text Available The red turpentine beetle (RTB, Dendroctonus valens LeConte (Coleoptera: Curculionidae, Scolytinae, is a destructive invasive pest of conifers which has become the second most important forest pest nationwide in China. Dendroctonus valens is known to use host odors and aggregation pheromones, as well as non-host volatiles, in host location and mass-attack modulation, and thus antennal olfaction is of the utmost importance for the beetles' survival and fitness. However, information on the genes underlying olfaction has been lacking in D. valens. Here, we report the antennal transcriptome of D. valens from next-generation sequencing, with the goal of identifying the olfaction gene repertoire that is involved in D. valens odor-processing.We obtained 51 million reads that were assembled into 61,889 genes, including 39,831 contigs and 22,058 unigenes. In total, we identified 68 novel putative odorant reception genes, including 21 transcripts encoding for putative odorant binding proteins (OBP, six chemosensory proteins (CSP, four sensory neuron membrane proteins (SNMP, 22 odorant receptors (OR, four gustatory receptors (GR, three ionotropic receptors (IR, and eight ionotropic glutamate receptors. We also identified 155 odorant/xenobiotic degradation enzymes from the antennal transcriptome, putatively identified to be involved in olfaction processes including cytochrome P450s, glutathione-S-transferases, and aldehyde dehydrogenase. Predicted protein sequences were compared with counterparts in Tribolium castaneum, Megacyllene caryae, Ips typographus, Dendroctonus ponderosae, and Agrilus planipennis.The antennal transcriptome described here represents the first study of the repertoire of odor processing genes in D. valens. The genes reported here provide a significant addition to the pool of identified olfactory genes in Coleoptera, which might represent novel targets for insect management. The results from our study also will assist with evolutionary
Lin, Ching-Hsuan; Kabrawala, Shail; Fox, Emily P.; Nobile, Clarissa J.; Johnson, Alexander D.; Bennett, Richard J.
Candida albicans can stochastically switch between two phenotypes, white and opaque. Opaque cells are the sexually competent form of C. albicans and therefore undergo efficient polarized growth and mating in the presence of pheromone. In contrast, white cells cannot mate, but are induced – under a specialized set of conditions – to form biofilms in response to pheromone. In this work, we compare the genetic regulation of such “pheromone-stimulated” biofilms with that of “conventional” C. albicans biofilms. In particular, we examined a network of six transcriptional regulators (Bcr1, Brg1, Efg1, Tec1, Ndt80, and Rob1) that mediate conventional biofilm formation for their potential roles in pheromone-stimulated biofilm formation. We show that four of the six transcription factors (Bcr1, Brg1, Rob1, and Tec1) promote formation of both conventional and pheromone-stimulated biofilms, indicating they play general roles in cell cohesion and biofilm development. In addition, we identify the master transcriptional regulator of pheromone-stimulated biofilms as C. albicans Cph1, ortholog of Saccharomyces cerevisiae Ste12. Cph1 regulates mating in C. albicans opaque cells, and here we show that Cph1 is also essential for pheromone-stimulated biofilm formation in white cells. In contrast, Cph1 is dispensable for the formation of conventional biofilms. The regulation of pheromone- stimulated biofilm formation was further investigated by transcriptional profiling and genetic analyses. These studies identified 196 genes that are induced by pheromone signaling during biofilm formation. One of these genes, HGC1, is shown to be required for both conventional and pheromone-stimulated biofilm formation. Taken together, these observations compare and contrast the regulation of conventional and pheromone-stimulated biofilm formation in C. albicans, and demonstrate that Cph1 is required for the latter, but not the former. PMID:23637598
Full Text Available This paper reports the occurrence of nineteen species of Long-horned Beetles (Cerambycidae and eleven species of Tortoise Beetles (Cassidinae from Tripura state, northeastern India. These include 11 species of Cerambycidae and seven species of Cassidinae, respectively, as new records from the state. Distribution of these beetles in different parts of the state are provided.
Fettig, Christopher J; McKelvey, Stephen R; Borys, Robert R; Dabney, Christopher P; Hamud, Shakeeb M; Nelson, Lori J; Seybold, Steven J
The western pine beetle, Dendroctonus brevicomis LeConte (Coleoptera: Curculionidae: Scolytinae), is a major cause of ponderosa pine, Pinus ponderosa Dougl. ex Laws., mortality in much of western North America. Currently, techniques for managing D. brevicomis infestations are limited. Verbenone (4,6,6-trimethylbicyclo [3.1.1] hept-3-en-2-one) is an antiaggregation pheromone of several Dendroctonus spp., including D. brevicomis, and it has been registered as a biopesticide for control of mountain pine beetle, Dendroctonus ponderosae Hopkins, and southern pine beetle, Dendroctonus frontalis Zimmermann. We evaluated the efficacy of a 5-g verbenone pouch [82%-(-); 50 mg/d] applied at 125 Ulha for protecting P. ponderosa stands (2 ha) from D. brevicomis attack over a 3-yr period. No significant differences in levels of D. brevicomis-caused tree mortality or the percentage of unsuccessfully attacked trees were found between verbenone-treated and untreated plots during each year or cumulatively over the 3-yr period. Laboratory analyses of release rates and chemical composition of volatiles emanating from verbenone pouches after field exposure found no deterioration of the active ingredient or physical malfunction of the release device. The mean release rate of pouches from all locations and exposure periods was 44.5 mg/d. In a trapping bioassay, the range of inhibition of the 5-g verbenone pouch was determined to be statistically constant 2 m from the release device. We discuss the implications of these and other results to the development of verbenone as a semiochemical-based tool for management of D. brevicomis infestations in P. ponderosa stands.
Wei, Shu-Dong; Zhou, Hai-Chao; Lin, Yi-Ming; Liao, Meng-Meng; Chai, Wei-Ming
The structures of the condensed tannins from leaf, stem bark and root bark of Acacia confusa were characterized by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis, and their antioxidant activities were measured using 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging and ferric reducing/antioxidant power (FRAP) assays. The results showed that the condensed tannins from stem bark and root bark include propelargonidin and procyanidin, and the leaf condensed tannins include propelargonidin, procyanidin and prodelphinidin, all with the procyanidin dominating. The condensed tannins had different polymer chain lengths, varying from trimers to undecamers for leaf and root bark and to dodecamers for stem bark. The condensed tannins extracted from the leaf, stem bark and root bark all showed a very good DPPH radical scavenging activity and ferric reducing power.
Full Text Available Abstract Background Prunus yedoensis Matsum. is used as traditional medicine—‘Yaeng-Pi’ or ‘Hua-Pi’—in Japan and Korea. However, no studies have examined the pharmacological activities of the P. yedoensis bark. Only the antioxidant and antiviral activities of P. yedoensis fruit and the anti-hyperglycaemic effect of P. yedoensis leaf have been investigated. While studying the antihypertensive effects of several medicinal plants, we found that a methanol extract of P. yedoensis bark (MEPY had distinct vasorelaxant effects on rat aortic rings. Methods The aortic rings were removed from Sprague–Dawley rats and suspended in organ chambers containing 10 ml Krebs-Henseleit solution. The aortic rings were placed between 2 tungsten stirrups and connected to an isometric force transducer. Changes in tension were recorded via isometric transducers connected to a data acquisition system. Results MEPY relaxed the contraction induced by phenylephrine (PE both in endothelium-intact and endothelium-denuded aortic rings concentration dependently. However, the vasorelaxant effects of MEPY on endothelium-denuded aortic rings were lower than endothelium-intact aortic rings. The vasorelaxant effects of MEPY on endothelium-intact aortic rings were reduced by pre-treatment with l-NAME, methylene blue, or ODQ. However, pre-treatment with indomethacin, atropine, glibenclamide, tetraethylammonium, or 4-aminopyridine had no affection. In addition, MEPY inhibited the contraction induced by extracellular Ca2+ in endothelium-denuded rat thoracic aorta rings pre-contracted by PE (1 μM or KCl (60 mM in Ca2+-free solution. Conclusions Our results suggest that MEPY exerts its vasorelaxant effects via the activation of NO formation by means of l-Arg and NO-cGMP pathways and via the blockage of extracellular Ca2+ channels.
Licht, Tine Rask; Hammerum, Anette Marie; Jensen, Lars Bogø
The effect of synthetic sex pheromone on pheromone-inducible conjugation between the isogenic Enterococcus faecalis strains OG1RF and OG1SS was investigated in (i) Todd-Hewitt broth medium and (ii) intestinal mucus isolated from germ-free rats. In broth, the presence of synthetic pheromone cCF10...
Tinzaara, W.; Gold, C.S.; Kagezi, G.H.; Dicke, M.; Huis, van A.; Nankinga, C.; Tushemereirwe, W.; Ragama, P.E.
An on-farm study to evaluate the effect of pheromone trap density on the population of the banana weevil, Cosmopolites sordidus (Germar) (Col., Curculionidae) was conducted in Masaka district, Uganda. The pheromone used was Cosmolure+, a commercially available weevil aggregation pheromone. Forty-two
Antony, Binu; Soffan, Alan; Jakše, Jernej; Alfaifi, Sulieman; Sutanto, Koko D.; Aldosari, Saleh A.; Aldawood, Abdulrahman S.; Pain, Arnab
Our study provides important background information on the enzymes involved in pheromone biosynthesis. This information will be useful for the in vitro production of E. cautella sex pheromones and may provide potential targets for disrupting the pheromone-based communication system of E. cautella to prevent infestations.
Sex pheromone production in most moths is initiated following pheromone biosynthesis activating neuropeptide receptor (PBANR) activation. PBANR was initially cloned from pheromone glands (PGs) of Helicoverpa zea and Bombyx mori. The B. mori PBANR is characterized by a relatively long C-terminus that...
Wei; Zhou; Lin; Liao; Chai
The structures of the condensed tannins from leaf, stem bark and root bark of Acacia confusa were characterized by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis, and their antioxidant activities were measured using 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging and ferric reducing/antioxidant power (FRAP) assays. The results showed that the condensed tannins from stem bark and root bark include propelargonidin and procyanidi...
Siegert, C. M.; Renninger, H. J.; Karunarathna, S.; Hornslein, N.; Riggins, J. J.; Clay, N. A.; Tang, J. D.; Chaney, B.; Drotar, N.
Disturbances in forest ecosystems can alter functions like productivity, respiration, and nutrient cycling through the creation of biogeochemical hotspots. These events occur sporadically across the landscape, leading to uncertainty in terrestrial biosphere carbon models, which have yet to capture the full complexity of biotic and abiotic factors driving ecological processes in the terrestrial environment. Given the widespread impact of southern pine beetle on forest ecosystems throughout the southeastern United States, it is critical to management and planning activities to understand the role of these disturbances. As such, we hypothesize that bark beetle killed trees create biogeochemical hotspots in the soils surrounding their trunk as they undergo mortality due to (1) increased soil moisture from reductions in plant water uptake and increased stemflow production, (2) enhanced canopy-derived inputs of carbon and nitrogen, and (3) increased microbial activity and root mortality. In 2015, a field experiment to mimic a southern pine beetle attack was established by girdling loblolly pine trees. Subsequent measurements of throughfall and stemflow for water quantity and quality, transpiration, stem respiration, soil respiration, and soil chemistry were used to quantify the extent of spatial and temporal impacts of tree mortality on carbon budgets. Compared to control trees, girdled trees exhibited reduced water uptake within the first 6 months of the study and succumbed to mortality within 18 months. Over two years, the girdled trees generated 33% more stemflow than control trees (7836 vs. 5882 L m-2). Preliminary analysis of carbon and nitrogen concentrations and dissolved organic matter quality are still pending. In the surrounding soils, C:N ratios were greater under control trees (12.8) than under girdled trees (12.1), which was driven by an increase in carbon around control trees (+0.13 mg C mg-1 soil) and not a decrease around girdled trees (-0.01 mg C mg-1
trihydroxy-3/-(8//-acetoxy-7//-methyloctyl)-5, 6-dimethoxyflavone, a flavonoid isolated from the stem bark of Stereospermum kunthianum. The antidiarrhoeal activity was evaluated using rodent models with diarrhoea. The normal intestinal transit, ...
Methods: The macroscopic and microscopic features of the bark were studied, including the ... Conclusion: The findings of this study will facilitate pharmacognostic standardization of the plant ..... EN, Samuelsson G. Inventory of plants used in.
Antioxidant benzophenones and xanthones from the root bark of Garcinia smeathmannii. Alain Meli Lannang, Justin Komguem, Fernande Ngounou Ngninzeko, Jean Gustave Tangmouo, David Lontsi, Asma Ajaz, Muhammad Iqbal Choudhary, Beiban Luc Sondengam, Atta -ur-Rahman ...
Sex pheromone of cocoa pod borer (CPB), Conopomorpha cramerella, has previously been identified as a blend of (E,Z,Z)- and (E,E,Z)-4,6,10-hexadecatrienyl acetates and the corresponding alcohols. These pheromone components have been synthesized with modification of the existing method and relative at...
Ritter, F.J.; Persoons, C.J.
A review is given of recent pheromone work carried out in the Netherlands on Lepidoptera, cockroaches, pharaoh's ants and termites, special emphasis being given to isolation and identification aspects. The sex pheromones of three leaf roller moths (Tortricidae) have been isolated, identified and
Jacobson, M; Redfern, R E; Jones, W A; Aldridge, M H
Two sex pheromones have been isolated from the female southern armyworm moth, Prodenia eridania (Cramer), and identified as cis-9-tetradecen-1-ol acetate, identical with the sex pheromone of the fall armyworm moth, Spodoptera frugiperda (J. E. Smith), and cis-9,trans-12-tetradecadien-1-ol acetate.
Pankiw, Tanya; Roman, Roman; Sagili, Ramesh R.; Zhu-Salzman, Keyan
The success of a species depends on its ability to assess its environment and to decide accordingly which behaviors are most appropriate. Many animal species, from bacteria to mammals, are able to communicate using interspecies chemicals called pheromones. In addition to exerting physiological effects on individuals, for social species, pheromones communicate group social structure. Communication of social structure is important to social insects for the allocation of its working members into coordinated suites of behaviors. We tested effects of long-term treatment with brood pheromone on suites of honey bee brood rearing and foraging behaviors. Pheromone-treated colonies reared significantly greater brood areas and more adults than controls, while amounts of stored pollen and honey remained statistically similar. Brood pheromone increased the number of pollen foragers and the pollen load weights they returned. It appeared that the pheromone-induced increase in pollen intake was directly canalized into more brood rearing. A two-way pheromone priming effect was observed, such that some workers from the same age cohorts showed an increased and extended capacity to rear larvae, while others were recruited at significantly younger ages into pollen-specific foraging. Brood pheromone affected suites of nursing and foraging behaviors allocating worker and pollen resources associated with an important fitness trait, colony growth.
Nielsen, O; Davey, William John; Egel, R
Loss of ras1+ function renders fission yeast cells unable to undergo morphological changes in response to mating pheromones, whereas cells carrying activated mutations in ras1 are hyper-responsive. This has led to the suggestion that the ras1 gene product plays a role in mating pheromone signal...
Muyama, Hiromi; Kiyokawa, Yasushi; Inagaki, Hideaki; Takeuchi, Yukari; Mori, Yuji
Rats are known to emit a series of ultrasonic vocalizations, termed 22-kHz calls, when exposed to distressing stimuli. Pharmacological studies have indicated that anxiety mediates 22-kHz calls in distressed rats. We previously found that exposure to the rat alarm pheromone increases anxiety in rats. Therefore, we hypothesized that the alarm pheromone would increase 22-kHz calls in pheromone-exposed rats. Accordingly, we tested whether exposure to the alarm pheromone induced 22-kHz calls, as well as whether the alarm pheromone increased 22-kHz calls in response to an aversive conditioned stimulus (CS). Rats were first fear-conditioned to an auditory and contextual CS. On the following day, the rats were either exposed to the alarm pheromone or a control odor that was released from the neck region of odor-donor rats. Then, the rats were re-exposed to the aversive CS. The alarm pheromone neither induced 22-kHz calls nor increased 22-kHz calls in response to the aversive CS. In contrast, the control odor unexpectedly reduced the total number and duration of 22-kHz calls elicited by the aversive CS, as well as the duration of freezing. These results suggest that the alarm pheromone does not affect 22-kHz calls in rats. However, we may have found evidence for an appeasing olfactory signal, released from the neck region of odor-donor rats. Copyright © 2016 Elsevier Inc. All rights reserved.
Wertheim, B.; Allemand, R.; Vet, L.E.M.; Dicke, M.
The effects of an aggregation pheromone on individual behaviour and food web interactions were investigated in two ecological communities, using Drosophila melanogaster and D. simulans as focal species. 2. Fruit substrates with aggregation pheromone were significantly more attractive to adult D.
Breuer, Rebecca J; Bandyopadhyay, Arpan; O'Brien, Sofie A; Barnes, Aaron M T; Hunter, Ryan C; Hu, Wei-Shou; Dunny, Gary M
In Enterococcus faecalis, sex pheromone-mediated transfer of antibiotic resistance plasmids can occur under unfavorable conditions, for example, when inducing pheromone concentrations are low and inhibiting pheromone concentrations are high. To better understand this paradox, we adapted fluorescence in situ hybridization chain reaction (HCR) methodology for simultaneous quantification of multiple E. faecalis transcripts at the single cell level. We present direct evidence for variability in the minimum period, maximum response level, and duration of response of individual cells to a specific inducing condition. Tracking of induction patterns of single cells temporally using a fluorescent reporter supported HCR findings. It also revealed subpopulations of rapid responders, even under low inducing pheromone concentrations where the overall response of the entire population was slow. The strong, rapid induction of small numbers of cells in cultures exposed to low pheromone concentrations is in agreement with predictions of a stochastic model of the enterococcal pheromone response. The previously documented complex regulatory circuitry controlling the pheromone response likely contributes to stochastic variation in this system. In addition to increasing our basic understanding of the biology of a horizontal gene transfer system regulated by cell-cell signaling, demonstration of the stochastic nature of the pheromone response also impacts any future efforts to develop therapeutic agents targeting the system. Quantitative single cell analysis using HCR also has great potential to elucidate important bacterial regulatory mechanisms not previously amenable to study at the single cell level, and to accelerate the pace of functional genomic studies.
Geerdink, Danny; Buter, Jeffrey; van Beek, Teris A.; Minnaard, Adriaan J.
Virgin females of the parasitoid wasp Trichogramma turkestanica produce minute amounts of a sex pheromone, the identity of which has not been fully established. The enantioselective synthesis of a putative component of this pheromone, (6S,8S,10S)-4,6,8,10-tetramethyltrideca-2E,4E-dien-1-ol (2), is