| effects of oxidant air pollutants on western pine beetle (coleoptera: scolytidae) populations in southern california. | the attack rates, brood survival, and emergence rates of the western pine beetle, dendroctonus brevicomis leconte, and incidence of entomophagus associates, were compared between photochemical oxidant damaged, and apparently healthy, ponderosa pine trees, pinus ponderosa dougl. ex laws in the san bernardino forest in southern california. the results from this study suggest that oxidant-damaged trees attacked by western pine beetle produced about the same total brood with lower initial attacks wh ... | 1997 | 15093407 |
| effectiveness of bifenthrin (onyx) and carbaryl (sevin sl) for protecting individual, high-value conifers from bark beetle attack (coleoptera: curculionidae: scolytinae) in the western united states. | 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 substantial impact. the value of these individual trees, cost of removal, and loss of esthetics may justify protection until the main thru ... | 2006 | 17066800 |
| 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. | 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 have common pheromone components, except for exo-brevicomin, which is produced by d. brevicomis. we predicted that d. frontalis would not respond t ... | 2008 | 18348798 |
| lack of genetic differentiation in aggressive and secondary bark beetles (coleoptera: curculionidae, scolytinae) from arizona. | bark beetles (coleoptera: curculionidae, scolytinae) play an important role as disturbance agents in ponderosa pine (pinus ponderosa douglas ex lawson) forests of arizona. however, from 2001 to 2003, elevated bark beetle activity caused unprecedented levels of ponderosa pine mortality. a better understanding of the population structure of these species will facilitate analysis of their dispersal patterns and improve management strategies. here, we use fluorescently labeled amplified fragment len ... | 2008 | 18559189 |
| effects of gallery density and species ratio on the fitness and fecundity of two sympatric bark beetles (coleoptera: curculionidae). | interspecific interactions among tree-killing bark beetle species may have ecologically important consequences on beetle population dynamics. using two tree-killing beetle species (dendroctonus brevicomis and d. frontalis), we performed observational and experimental studies to verify cross-attraction and co-colonization under field conditions in northern arizona and test the effects of gallery density and species ratio on response variables of average gallery length, offspring size (progeny fit ... | 2009 | 19508772 |
| efficacy of verbenone for protecting ponderosa pine stands from western pine beetle (coleoptera: curculionidae: scolytinae) attack in california. | 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 ... | 2009 | 19886449 |
| evaluation of multiple funnel traps and stand characteristics for estimating western pine beetle-caused tree mortality. | 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. this study was designed to quantify relationships between western pine beetle trap catches [including those of its primary invertebrate predator temnochila chlorodia (mannerheim) (coleoptera: trogositidae)], and levels of tree mortality attributed to western pine beetle at 44 trapping sit ... | 2009 | 20069846 |
| impacts of silvicultural thinning treatments on beetle trap captures and tree attacks during low bark beetle populations in ponderosa pine forests of northern arizona. | 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 pr ... | 2010 | 21061969 |
| interactions between the yeast ogataea pini and filamentous fungi associated with the western pine beetle. | ecologically important microbes other than filamentous fungi can be housed within the fungal-transport structures (mycangia) of dendroctonus bark beetles. the yeast ogataea pini (saccharomycetales: saccharomycetaceae) was isolated from the mycangia of western pine beetle (dendroctonus brevicomis) populations in northern arizona (usa) with a frequency of 56%. we performed a series of in vitro assays to test whether volatile organic compounds produced by o. pini affected radial growth rates of mut ... | 2010 | 21085946 |
| reciprocal interactions between the bark-beetle associated yeast ogataea pini and host plant phytochemistry. | here we report the first experiments testing reciprocal effects between the bark beetle-associated yeast, ogataea pini, and phytochemicals present in tree tissues (pinus ponderosa). we tested two hypotheses: (1) tree phytochemicals mediate o. pini growth; and (2) o. pini affects chemical composition of plant tissues. we tested six monoterpenes on o. pini biomass growth in vitro and found that most monoterpenes inhibited o. pini growth; however, mean o. pini biomass increased 21.5% when treated w ... | 2011 | 21659459 |
| oleoresin chemistry mediates oviposition behavior and fecundity of a tree-killing bark beetle. | many herbivores are sensitive to the secondary chemistry of their host plants. however, the influence of pine secondary chemicals (monoterpenes) on bark beetle fitness is poorly understood. we tested the hypothesis that the monoterpene composition of the phloem oleoresin of ponderosa pine, pinus ponderosa var scopulorum, mediates rates of host acceptance, oviposition behavior, and fecundity of the western pine beetle, dendroctonus brevicomis. we performed reciprocal rearing experiments, controll ... | 2011 | 22072184 |
| western pine beetle populations in arizona and california differ in the composition of their aggregation pheromones. | we compared pheromone production and response for populations of western pine beetle, dendroctonus brevicomis leconte, from sites in northern arizona and northern california. volatiles were collected from individuals of both sexes that had mined as a pair in a pinus ponderosa log for 1 d, and they were subsequently analyzed by gas chromatography coupled to mass-spectrometry. principal component analysis of quantities of dendroctonus pheromone components indicated strong site-associated clusterin ... | 2016 | 27125814 |
| broadscale specificity in a bark beetle-fungal symbiosis: a spatio-temporal analysis of the mycangial fungi of the western pine beetle. | whether and how mutualisms are maintained through ecological and evolutionary time is a seldom studied aspect of bark beetle-fungal symbioses. all bark beetles are associated with fungi and some species have evolved structures for transporting their symbiotic partners. however, the fungal assemblages and specificity in these symbioses are not well known. to determine the distribution of fungi associated with the mycangia of the western pine beetle (dendroctonus brevicomis), we collected beetles ... | 2014 | 25004995 |
| efficacy of "verbenone plus" for protecting ponderosa pine trees and stands from dendroctonus brevicomis (coleoptera: curculionidae) attack in british columbia and california. | the western pine beetle, dendroctonus brevicomis leconte (coleoptera: curculionidae, scolytinae), is a major cause of ponderosa pine, pinus ponderosa douglas ex lawson, mortality in much of western north america. we review several years of research that led to the identification of verbenone plus, a novel four-component semiochemcial blend [acetophenone, (e)-2-hexen-1-ol + (z)-2-hexen-1-ol, and (-)-verbenone] that inhibits the response of d. brevicomis to attractant-baited traps, and examine the ... | 2012 | 23156163 |
| plant secondary chemistry mediates the performance of a nutritional symbiont associated with a tree-killing herbivore. | many herbivores consume microbial food sources in addition to plant tissues for nutrition. despite the ubiquity of herbivore-microbe feeding associations, few studies examine how host plant phenotypes affect microbial symbionts of herbivores. we tested the hypothesis that chemical polymorphism in a plant population mediates the performance of nutritional microbial symbionts. we surveyed the composition of ponderosa pine resin in northern arizona, usa, for variation in six monoterpenes, and we ap ... | 2012 | 22624323 |
| responses of dendroctonus brevicomis (coleoptera: curculionidae) in behavioral assays: implications to development of a semiochemical-based tool for tree protection. | currently, techniques for managing western pine beetle, dendroctonus brevicomis leconte (coleoptera: curculionidae, scolytinae), infestations are limited to tree removals (thinning) that reduce stand density and presumably host susceptibility, and/or the use of insecticides to protect individual trees. there continues to be significant interest in developing an effective semiochemical-based tool for protecting trees from d. brevicomis attack, largely as an alternative to conventional insecticide ... | 2012 | 22420267 |
| acetophenone as an anti-attractant for the western pine beetle, dendroctonus brevicomis leconte (coleoptera: scolytidae). | host location and colonization by bark beetles is dependent upon the relative and absolute amounts of attractant and antiattractant compounds available. many investigations have lead to use of antiattractants for the management of these pests and have been especially focused on verbenone. however, recent studies have identified new antiattractants for several species of bark beetles. we report results of recent investigations of the response of western pine beetle, dendroctonus brevicomis lecont ... | 2007 | 17318432 |
| nonhost angiosperm volatiles and verbenone disrupt response of western pine beetle, dendroctonus brevicomis (coleoptera: scolytidae), to attractant-baited traps. | nonhost angiosperm volatiles and verbenone were tested for their ability to disrupt the response of western pine beetle, dendroctonus brevicomis leconte (coleoptera: scolytidae), to attractant-baited multiple funnel traps. verbenone significantly reduced attraction; however, no difference was observed between 4 and 50 mg/24-h release rates. combinations of six bark volatiles (benzyl alcohol, benzaldehyde, trans-conophthorin, guaiacol, nonanal, and salicylaldehyde), three green leaf volatiles [(e ... | 2005 | 16539131 |
| field response of ips paraconfusus, dendroctonus brevicomis, and their predators to 2-methyl-3-buten-2-ol, a novel alcohol emitted by ponderosa pine. | methylbutenol (mbo) is a major component of the aggregation pheromone of the european spruce beetle ips typographus and also has been found to be emitted in large amounts by several species of pine native to western north america. this study investigates the influence this signal may have on the behavior of north american bark beetles and examines whether mbo functions as a defensive compound for emitting pines. the response of two north american bark beetles (ips paraconfusus and dendroctonus b ... | 2002 | 12371811 |
| response ofdendroctonus brevicomis le conte (coleoptera: scolytidae) to different release rates and ratios of aggregation semiochemicals and the inhibitors verbenone and ipsdienol. | the response of western pine beetle,dendroctonus brevicomis le conte, to different release rates of the aggregation semiochemicals (attractants)exo-brevicomin, frontalin, and myrcene and the inhibitors verbenone and ipsdienol was investigated. release rates of verbenone ranging from 0.18 mg/ 24 hr to 1.2 mg/24 hr did not result in significant reductions in mean trap catch ofd. brevicomis. in contrast, very low release rates of ipsdienol (0.02-0.4 mg/24 hr) significantly reduced trap catch compar ... | 1994 | 24241925 |
| influence of aggregation inhibitors (verbenone and ipsidenol) on landing and attack behavior ofdendroctonus brevicomis (coleoptera: scolytidae). | the influence of the aggregation inhibitors verbenone and ipsdienol on the response of western pine beetle,dendroctonus brevicomis, to attractive host trees was investigated. paired ponderosa pine trees (pinus ponderosa) were baited with aggregation semiochemicals to stimulate mass attack. one tree in each pair received an inhibitor treatment consisting of five sets of two verbenone and two ipsdienol dispensers spaced 1 m apart vertically along the tree bole. beetle landing was monitored with st ... | 1994 | 24242655 |
| novel diffusion-dilution method for release of semiochemicals: testing pheromone component ratios on western pine beetle. | each of the pheromone components of the western pine beetle,dendroctonus brevicomis lec. (coleoptera: scolytidae), exo-brevicomin (e) and frontalin (f), were released in the forest at various ratios 0.01∶1, 0.1∶1, or 1∶1 to a constant dose of the opposite component (e or f) plus the host monoterpene myrcene (m), which were each released at 1.5 mg/day. the components were released by a new method that combines the principles of chemical diffusion through a tube with mole percentage dilution of th ... | 1988 | 24277005 |
| interruption of response ofdendroctonus brevicomis to attractive pheromone by release of pheromone at several rates and spacings. | the number of western pine beetles,dendroctonus brevicomis, trapped at the center of three 90 × 90-m plots was reduced during a 16-hr period after surrounding an attractive source ofexo-brevicomin, frontalin, and myrcene with 16, 48, or 168 sources of the same attractant. compounds were released from the center of the plot at 1 mg/16 hr/compound, and from the surrounding sources at 4-280 mg/16 hr/compound. about half of these amounts was released between 1530 hr and 1930 hr, the period of peak b ... | 1987 | 24301361 |
| behavior of the western pine beetle during host colonization. | after living ponderosa pines were baited with either female-infested bolts or synthetic pheromones,dendroctonus brevicomis were caught on sticky screens throughout trapping periods of 15-46 days; however, large numbers of beetles were trapped during only a small portion (5-10 days) of these trapping periods. the most attractive portions of trees attacked contained 3-6 beetles dm(2), in galleries ca. 2 cm long. catch increased following addition of males to female-infested bolts, supporting the h ... | 1985 | 24310387 |
| field response ofdendroctonus brevicomis toexo-brevicomin, frontalin, and myrcene released at two proportions and three levels. | racemicezo-brevicomin, racemic frontalin, and myrcene were released at two proportions (5∶1∶400 and 1∶1∶1), each at three levels (1 ×, 10 ×, and 100 ×) in a ponderosa pine forest in central california. the 5∶1∶400 mix was based on an estimate of the relative amounts released from a ponderosa pine under attack by the western pine beetle,dendroctonus brevicomis. mored. brevicomis were trapped at a source of the three compounds released at 5∶1∶400 than were trapped at a source released at 1∶1∶1, at ... | 1985 | 24310220 |
| attractive and inhibitory pheromones produced in the bark beetle,dendroctonus brevicomis, during host colonization: regulation of inter- and intraspecific competition. | quantities of attractive (exo-brevicomin and frontalin) and inhibitory (trans-verbenol, verbenone, and ipsdienol) pheromones were monitored in both sexes ofdendroctonus brevicomis during their colonization of a ponderosa pine. verbenone was found in males in the greatest amounts at the time of landing, and it declined more rapidly than the other pheromones in either sex. the amounts of frontalin andexo-brevicomin in males and females, respectively, increased after initial boring within the host ... | 1984 | 24318780 |
| bark beetle conversion of a plant compound to a sex-specific inhibitor of pheromone attraction. | both sexes of the bark beetle dendroctonus brevicomis convert the (+) and (-) enantiomers of the tree terpene alpha-pinene to the corresponding enantiomers of trans-verbenol at about equal rates. (-)-trans-verbenol inhibited the response of females, but not of males, to a mixture of attractive pheromone components. since the female initiates the attack on a pine tree, (-)-trans-verbenol may play a role in reducing intraspecific competition for breeding areas. | 1983 | 17749538 |
| male-specific conversion of the host plant compound, myrcene, to the pheromone, (+)-ipsdienol, in the bark beetle,dendroctonus brevicomis. | when both sexes of the bark beetle,dendroctonus brevicomis leconte, were exposed to vapors of myrcene from ponderosa pine, only the male produced (+)-ipsdienol. in the field, racemic ipsdienol significantly reduced the attraction of both sexes in flight to a mixture of myrcene and the aggregation pheromones,exo-brevicomin and frontalin. this suggests that ipsdienol may be involved in regulating colonization density ofd. brevicomis. the implications of the biosynthesis of various enantiomers of i ... | 1982 | 24414947 |
| interruption of response ofdendroctonus brevicomis to its attractive pheromone by components of the pheromone. | the catch of the western pine beetle,dendroctonus brevicomis, at an attractive source of racemicexo-brevicomin, racemic frontalin, and myrcene was reduced by surrounding the source with a grid of 48 stations releasing all three compounds together, orexo-brevicomin alone or myrcene alone. each compound was released at the rate of 2 mg/24 hr/station. the catch at an attractive bolt cut from a tree being colonized byd. brevicomis was not reduced byexo-brevicomin, but was reduced by the combination ... | 1981 | 24420438 |
| host selection behavior of bark beetles (coleoptera: scolytidae) attackingpinus ponderosa, with special emphasis on the western pine beetle,dendroctonus brevicomis. | detection of weakened hosts from a distance by bark beetles through olfaction was investigated in field experiments. no significant numbers of scolytidae were attracted to anaerobically treated pine bolts, stem disks, or sugar and ponderosa pine bark including phloem. treatment of living trees with cacodylic acid induced attacks bydendroctonus brevicomis, d. ponderosae, ips latidens, gnathotrichus retusus, andpityophthorus scalptor, beginning two weeks after treatment. there was no significant d ... | 1981 | 24420427 |
| interspecific effects of pheromones on the attraction of the bark beetles,dendroctonus brevicomis andips paraconfusus in the laboratory. | dendroctonus brevicomis was attracted to a mixture of theips paraconfusus pheromones, ipsenol,cis-verbenol, and ipsdienol at 10(-9) g each/μl but was not attracted to these pheromones at higher and lower release rates.i. paraconfusus was not attracted to thed. brevicomis pheromonesexo-brevicomin, frontalin, and myrcene at any release rate tested. increased release rates of a mixture of the three pheromones ofi. paraconfusus inhibited the attraction ofd. brevicomis to its synthetic pheromones. a ... | 1981 | 24420423 |
| a new preparation of acetylenic ketones and application to the synthesis of exo-brevicomin, the pheromone from dendroctonus brevicomis. | | 1977 | 559730 |
| western pine beetle: specificity among enantiomers of male and female components of an attractant pheromone. | the flight response of both sexes of dendroctonus brevicomis to the mixture of myrcene, racemic frontalin, and (1r,5s,7r)-(+)-exo-brevicomin and to the mixture of myrcene, (1s,5r)-(-)-frontalin and racemic exo-brevicomin was significantly greater than the response to the same mixtures in which the antipodes were substituted. the flight response to these two mixtures was also greater than the response to the ternary mixture of myrcene, racemic frontalin, and racemic exo-brevicomin (mfe). the walk ... | 1976 | 1273574 |
| pheromones released during inter- and intra-sex response of the scolytid beetle dendroctonus brevicomis. | | 1974 | 4853618 |
| a redescription of the bark beetle nematode contortylenchus brevicomi: synonym contortylenchus barberus (nematoda : sphaerulariidae). | contortylenchus barberus is synonymized with c. brevicomi because their original separation was based on minor morphometric variations that are considered here to be intraspecific rather than interspeciflc. the ranges of body length and body width in measured specimens of c. brevicomi encompass those of the original description of c. brevicomi and c. barberus. the presence or absence of the caudal mucro is considered not a valid criterion for species differentiation. several of the morphometric ... | 1972 | 19319269 |
| western pine beetle: field response to its sex pheromone and a synergistic host terpene, myrcene. | in the field, both sexes of the western pine beetle, dendroctonus brevicomis, are attracted by the female-produced bicyclic ketal exo-brevicomin; this response is enhanced by myrcene (a constituent of the beetle's host, ponderosapine), which is not an attractant by itself. this synergism may be part of the phenomenon of the mass attack on its host. temnochila virescens chlorodia, one of the principal insectan predators of this beetle, is attracted by exo-brevicomin alone. | 1969 | 17772569 |