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Darrell W. Ross - One of the best experts on this subject based on the ideXlab platform.
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a biodegradable formulation of mch 3 methylcyclohex 2 en 1 one for protecting pseudotsuga menziesii from Dendroctonus pseudotsugae coleoptera curculionidae colonization
Journal of Economic Entomology, 2020Co-Authors: Gabriel G Foote, Darrell W. Ross, Christopher J Fettig, Justin B Runyon, Tom W Coleman, Monica L Gaylord, Andrew D Graves, Joel D Mcmillin, Leif A Mortenson, Agenor MafranetoAbstract:Douglas-fir, Pseudotsuga menziesii (Mirb.) Franco, trees and stands can be protected from Douglas-fir beetle, Dendroctonus pseudotsugae Hopkins (DFB)-caused mortality by application of synthetic formulations of the beetle's antiaggregation pheromone, 3-methylcyclohex-2-en-1-one (MCH). A biodegradable formulation of MCH, SPLAT MCH, was developed and evaluated for protecting individual Douglas-fir trees and small stands from colonization and mortality by DFB. In an individual-tree experiment in Idaho, both MCH bubble capsules and SPLAT MCH significantly reduced the proportion of treated trees colonized and killed by DFB compared to untreated controls. SPLAT MCH was as effective as MCH bubble capsules for protecting individual trees. Both MCH bubble capsules and SPLAT MCH significantly reduced the proportion of trees colonized and killed by DFB within 0.04-ha circular plots surrounding each treated tree compared to untreated controls. In 0.41 ha stands in New Mexico, both MCH bubble capsules and SPLAT MCH significantly reduced the proportion of trees colonized and killed by DFB compared to untreated controls, again with no differences observed between MCH treatments. In a similar stand level trial in Idaho, neither MCH treatment significantly reduced the proportion of trees colonized by DFB, and only MCH bubble capsules significantly reduced levels of tree mortality compared to untreated controls, but no significant difference was observed between SPLAT MCH and MCH bubble capsules. Overall, the results indicate that SPLAT MCH is as effective as MCH bubble capsules for protecting individual trees and small stands of Douglas-fir from DFB-caused mortality.
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Evaluating High Release Rate MCH (3-Methylcyclohex-2-en-1-one) Treatments for Reducing Dendroctonus pseudotsugae (Coleoptera: Curculionidae) Infestations.
Journal of Economic Entomology, 2016Co-Authors: Harrison M. Brookes, Darrell W. Ross, Tara M. Strand, Harold W. Thistle, Iral R. Ragenovich, Laura L. LowreyAbstract:Current recommendations for applying the antiaggregation pheromone 3-methylcyclohex-2-en-1-one (MCH) to protect live trees from Douglas-fir beetle, Dendroctonus pseudotsugae Hopkins, infestation are to space individual passive releasers (MCH bubble capsules) on a 12- by 12-m grid throughout areas to be protected. Previous field studies and a theoretical study using a puff dispersion model to predict pheromone concentrations have shown that releasers emitting higher rates of MCH spaced farther apart may be as effective as the established standard treatment. During 2012 and 2013, we tested higher release rates of MCH at correspondingly wider spacings to keep the total amount of MCH released per unit area equal in all treatments. In 2012 near Challis, ID, treatments included the established standard release rate and spacing, four and six times the standard release rate at correspondingly wider spacings, and an untreated control. In 2013 near Ketchum, ID, treatments included the established standard release rate and spacing, five and seven times the standard release rate at correspondingly wider spacings, and an untreated control. Results from both years indicated that all MCH treatments were equally effective in reducing Douglas-fir beetle infestation. Using higher release rate formulations at wider spacings will reduce labor costs of installing MCH treatments, and, in cases where it is necessary, retrieving the releasers as well. In addition to reducing labor costs, the revised treatment protocol may increase the feasibility of treating areas that currently may not be possible due to treatment costs.
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Predicting Dendroctonus pseudotsugae (Coleoptera: Curculionidae) Antiaggregation Pheromone Concentrations using an Instantaneous Puff Dispersion Model
Journal of economic entomology, 2012Co-Authors: Tara M. Strand, Darrell W. Ross, Harold W. Thistle, Iral R. Ragenovich, Ivonne Matos Guerra, Brian LambAbstract:An instantaneous puff dispersion model was used to assess concentration fields of the Douglas-fir beetle, Dendroctonus pseudotsugae Hopkins, antiaggregation pheromone, 3-methylcyclohex-2-en-1-one (MCH), within a 1-ha circular plot. Several combinations of MCH release rate and releaser spacing were modeled to theoretically analyze optimal deployment strategies. The combinations of MCH release rate and releaser spacing used in the modeling exercise were based on results of previous field studies of treatment efficacy. Analyses of model results suggest that a release rate up to six times the initial standard, at a correspondingly wider spacing to keep the total amount of pheromone dispersed per unit area constant, may be effective at preventing Douglas-fir beetle infestation. The model outputs also provide a visual representation of pheromone dispersion patterns that can occur after deployment of release devices in the field. These results will help researchers and practitioners design more effective deployment strategies.
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Douglas-fir beetle lipid levels in relation to tree physical characteristics
Journal of the Entomological Society of British Columbia, 2004Co-Authors: Kevin J Dodds, Darrell W. RossAbstract:The relationship of Douglas-fir beetle, Dendroctonus pseudotsugae Hopkins, brood adult lipid levels and position of development along infested tree boles was investigated. In addition, the effects of phloem and bark thickness on brood adult lipid levels were also tested. There were no significant differences (P > 0.05) in brood adult lipid levels in relation to bole position, phloem thickness, or bark thickness found in this study. Numbers of attacks, larval mines, brood adults, and parasitoid cocoons did not differ significantly by tree bole position. Results from this study suggest Douglas-fir beetle does not benefit, in the form of increased lipid levels, from oviposition at different bole positions.
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Elution rate and spacing of antiaggregation pheromone dispensers for protecting live trees from Dendroctonus pseudotsugae (Coleoptera: Scolytidae)
Journal of Economic Entomology, 2002Co-Authors: Darrell W. Ross, Gary E Daterman, Kenneth E. GibsonAbstract:The antiaggregation pheromone 3-methylcyclohex-2-en-1-one (MCH) is highly effective in preventing the infestation of high-risk trees by Douglas-fir beetle, Dendroctonus pseudotsugae Hopkins. A large portion of the cost of an MCH treatment is related to the time applicators spend walking through an area dispersing the formulated pheromone. Application of fewer MCH dispensers eluting at a higher rate than those currently registered for operational use could potentially reduce treatment costs. Two higher elution rates, 6 and 18 mg/d per dispenser, were compared with the current standard of 2 mg/d per dispenser and an untreated control on 1-ha circular plots. Dispensers were spaced 5, 15, and 44 m apart around the plot perimeters eluting 2, 6, and 18 mg/d, respectively. The nominal dose of MCH was 144 mg/ha/d on all plots. Percentages of Douglas-fir trees ≥20 cm diameter at breast height mass attacked by Douglas-fir beetle were significantly lower on plots treated with dispensers eluting 2 and 6 mg/d and spaced 5 and 15 m apart, respectively, compared with the untreated control. Infestation rate on plots treated with dispensers eluting 18 mg/d and spaced 44 m apart was not significantly different from the control. Douglas-fir beetle abundance and host tree availability were similar on all plots. These results indicate that MCH dispensers eluting 6 mg/d (three times the current standard rate) and spaced 15 m apart (three times existing standard distance) can effectively prevent Douglas-fir beetle infestations.
H D Pierce - One of the best experts on this subject based on the ideXlab platform.
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a survey of antennal responses by five species of coniferophagous bark beetles coleoptera scolytidae to bark volatiles of six species of angiosperm trees
Chemoecology, 2000Co-Authors: John H. Borden, H D PierceAbstract:Using Porapak Q traps, we collected the bark volatiles of six angiosperm trees native to British Columbia: black cottonwood, Populus trichocarpa Torr. & A. Gray (Salicaceae), trembling aspen, P. tremuloides Michx. (Salicaceae), paper birch, Betula papyrifera Marsh. (Betulaceae), bigleaf maple, Acer macrophyllum Pursh (Aceraceae), red alder, Alnus rubra Bong. (Betulaceae), and Sitka alder, A. viridis ssp. sinuata (Regel) A. Love & D. Love (Betulaceae). Utilising coupled gas chromatographic-electroantennographic detection analysis, the captured volatiles were assayed for antennal responses in five species of coniferophagous bark beetles (Coleoptera: Scolytidae), sympatric with most or all of the angiosperm trees: the Douglas-fir beetle, Dendroctonus pseudotsugae Hopkins, the mountain pine beetle, D. ponderosae Hopkins, the spruce beetle, D. rufipennis (Kirby), the western balsam bark beetle, Dryocoetes confusus Swaine, and the pine engraver, Ips pini (Say). The identities of 25 antennally-active compounds were determined by coupled gas chromatographic-mass spectroscopic analysis, and co-chromatographic comparisons with authentic chemicals. The compounds identified were: hexanal, (E)-2-hexenal, (Z)-3-hexen-1-ol, 1-hexanol, heptanal, α-pinene, frontalin, benzaldehyde, β-pinene, 2-hydroxycyclohexanone, 3-carene, limonene, β-phellandrene, benzyl alcohol, (E)-ocimene, salicylaldehyde, conophthorin, guaiacol, nonanal, methyl salicylate, 4-allylanisole, decanal, thymol methyl ether, (E)-nerolidol, and dendrolasin. A number of these compounds are known semiochemicals that are active in the behaviour of other organisms, including bark beetles, suggesting a high degree of semiochemical parsimony. Antennally-active compounds ranged from seven in A. viridis to 17 in P. trichocarpa. The fewest number of compounds (9) were detected by I. pini and the largest number (24) were detected by D. pseudotsugae. Six compounds excited the antennae of all five species of bark beetles. The large number of antennally-active compounds detected in common by numerous bark beetles and present in common in numerous nonhost trees supports the hypothesis of olfaction-based recognition and avoidance of nonhost angiosperm trees during the process of host selection by coniferophagous bark beetles.
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Dendroctonus pseudotsugae hopkins coleoptera scolytidae production of and response to enantiomers of 1 methylcyclohex 2 en 1 ol
Journal of Chemical Ecology, 1992Co-Authors: B S Lindgren, H D Pierce, Gerhard Gries, K MoriAbstract:Female Douglas-fir beetles,Dendroctonus pseudotsugae, produced an average 45∶55 mixture of the (S)-(−)- and (R)-(+)-enantiomers of 1-methylcyclohex-2-en-1-ol (MCOL). The (S)-(−)∶(R)-(+) ratio of 3-methylcyclohex-2-en-1-ol (seudenol) produced by this population of females was 34∶66. Lindgren funnel traps baited with (R)-(+)-MCOL attracted significantly more males and females than (S)-(−)-MCOL-baited traps, which captured significantly more beetles than unbaited controls. The combined effect of the enantiomers was additive, rather than synergistic. Either enantiomer of MCOL increased catches by frontalin-baited traps. Racemic MCOL can be used for trapping Douglas-fir beetles in south-central British Columbia.
John H. Borden - One of the best experts on this subject based on the ideXlab platform.
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Angiosperm Bark Volatiles Disrupt Response of Douglas-Fir Beetle, Dendroctonus pseudotsugae, to Attractant-Baited Traps
Journal of Chemical Ecology, 2001Co-Authors: John H. BordenAbstract:Antennally active, bark-derived, angiosperm volatiles were tested singly and in groups for their ability to disrupt the response of the Douglas-fir beetle (DFB), Dendroctonus pseudotsugae, to attractant-baited multiple-funnel traps. One compound, conophthorin, was active alone in reducing the response of beetles to the baited traps. Further experiments showed disruptive activity in two aliphatic green-leaf alcohols [1-hexanol and (Z)-3-hexen-1-ol], as well as guaiacol and benzyl alcohol, and three aliphatic aldehydes [nonanal, hexanal, and (E)-2-hexenal] but not in two aromatic aldehydes (benzaldehyde and salicylaldehyde). Every binary combination that included conophthorin or any two of the other groups, except aromatic aldehydes, significantly reduced the response of beetles to baited traps. Various ternary mixtures and the complete mixture of all the groups were generally the most effective treatments. These results provide evidence that DFBs recognize and avoid nonhosts while flying rather than landing on candidate hosts and testing them while in contact with the tree. Nonhost angiosperm bark volatiles may have practical utility on their own or in combination with the antiaggregation pheromone 3-methylcyclohex-3-en-1-one (MCH) to protect single trees, logs, or stands from attack by the DFB.
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a survey of antennal responses by five species of coniferophagous bark beetles coleoptera scolytidae to bark volatiles of six species of angiosperm trees
Chemoecology, 2000Co-Authors: John H. Borden, H D PierceAbstract:Using Porapak Q traps, we collected the bark volatiles of six angiosperm trees native to British Columbia: black cottonwood, Populus trichocarpa Torr. & A. Gray (Salicaceae), trembling aspen, P. tremuloides Michx. (Salicaceae), paper birch, Betula papyrifera Marsh. (Betulaceae), bigleaf maple, Acer macrophyllum Pursh (Aceraceae), red alder, Alnus rubra Bong. (Betulaceae), and Sitka alder, A. viridis ssp. sinuata (Regel) A. Love & D. Love (Betulaceae). Utilising coupled gas chromatographic-electroantennographic detection analysis, the captured volatiles were assayed for antennal responses in five species of coniferophagous bark beetles (Coleoptera: Scolytidae), sympatric with most or all of the angiosperm trees: the Douglas-fir beetle, Dendroctonus pseudotsugae Hopkins, the mountain pine beetle, D. ponderosae Hopkins, the spruce beetle, D. rufipennis (Kirby), the western balsam bark beetle, Dryocoetes confusus Swaine, and the pine engraver, Ips pini (Say). The identities of 25 antennally-active compounds were determined by coupled gas chromatographic-mass spectroscopic analysis, and co-chromatographic comparisons with authentic chemicals. The compounds identified were: hexanal, (E)-2-hexenal, (Z)-3-hexen-1-ol, 1-hexanol, heptanal, α-pinene, frontalin, benzaldehyde, β-pinene, 2-hydroxycyclohexanone, 3-carene, limonene, β-phellandrene, benzyl alcohol, (E)-ocimene, salicylaldehyde, conophthorin, guaiacol, nonanal, methyl salicylate, 4-allylanisole, decanal, thymol methyl ether, (E)-nerolidol, and dendrolasin. A number of these compounds are known semiochemicals that are active in the behaviour of other organisms, including bark beetles, suggesting a high degree of semiochemical parsimony. Antennally-active compounds ranged from seven in A. viridis to 17 in P. trichocarpa. The fewest number of compounds (9) were detected by I. pini and the largest number (24) were detected by D. pseudotsugae. Six compounds excited the antennae of all five species of bark beetles. The large number of antennally-active compounds detected in common by numerous bark beetles and present in common in numerous nonhost trees supports the hypothesis of olfaction-based recognition and avoidance of nonhost angiosperm trees during the process of host selection by coniferophagous bark beetles.
K Mori - One of the best experts on this subject based on the ideXlab platform.
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Dendroctonus pseudotsugae hopkins coleoptera scolytidae production of and response to enantiomers of 1 methylcyclohex 2 en 1 ol
Journal of Chemical Ecology, 1992Co-Authors: B S Lindgren, H D Pierce, Gerhard Gries, K MoriAbstract:Female Douglas-fir beetles,Dendroctonus pseudotsugae, produced an average 45∶55 mixture of the (S)-(−)- and (R)-(+)-enantiomers of 1-methylcyclohex-2-en-1-ol (MCOL). The (S)-(−)∶(R)-(+) ratio of 3-methylcyclohex-2-en-1-ol (seudenol) produced by this population of females was 34∶66. Lindgren funnel traps baited with (R)-(+)-MCOL attracted significantly more males and females than (S)-(−)-MCOL-baited traps, which captured significantly more beetles than unbaited controls. The combined effect of the enantiomers was additive, rather than synergistic. Either enantiomer of MCOL increased catches by frontalin-baited traps. Racemic MCOL can be used for trapping Douglas-fir beetles in south-central British Columbia.
Gerardo Zuniga - One of the best experts on this subject based on the ideXlab platform.
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historical demography and phylogeography of a specialist bark beetle Dendroctonus pseudotsugae hopkins curculionidae scolytinae
Environmental Entomology, 2010Co-Authors: Enrico A Ruiz, John E Rinehart, Jane L Hayes, Gerardo ZunigaAbstract:Contemporary distribution of North American species has been shaped by past glaciation events during the Quaternary period. However, their effects were not as severe in the southern Rocky Mountains and Northern Mexico as elsewhere in North America. In this context, we test hypotheses about the historical demography of Dendroctonus pseudotsugae, based on 136 haplotypes of mitochondrial cytochrome oxidase I. The phylogenetic analysis yielded four haplogroups corresponding to northwestern United States and southwestern Canada (NUS), southwestern United States (Arizona, SUS), northwestern Mexico (Sierra Madre Occidental, SMOC), and northeastern Mexico (Sierra Madre Oriental, SMOR). Predictions of demographic expansion were examined through neutrality tests against population growth and mismatch distribution. Results showed that the NUS and SMOC haplogroups have experienced demographic expansion events, whereas the SUS and SMOR haplogroups have not. Divergence times between pairs of haplogroups were estimated from early to middle Pleistocene. The longer divergence time between NUS and all other haplogroups could be the result of refugia within the Pacific Northwest and northern Rocky Mountains and long-term isolation from southernmost populations in Mexico. The results obtained in this study are in agreement with the evolutionary history of the host Douglas-fir, as the warmer climates of interglacial periods pushed conifers northward of Colorado, New Mexico, and Arizona, whereas environmental changes reduced the population size of Douglas-fir and forced fragmentation of distribution range southward into northern Mexico.
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molecular and morphological analysis of Dendroctonus pseudotsugae coleoptera curculionidae scolytinae an assessment of the taxonomic status of subspecies
Annals of The Entomological Society of America, 2009Co-Authors: Enrico A Ruiz, Jane L Hayes, Javier Victor, Gerardo ZunigaAbstract:Dendroctonus pseudotsugae Hopkins infests Douglas-fir, Pseudotsuga menziesii (Mirb.) Franco, throughout the distribution of that tree species from British Columbia to northern Mexico. The subspecies Dendroctonus pseudotsugae barragani Furniss was described from the mountains of Chihuahua, Sierra Madre Occidental, Mexico, whereas the nominal subspecies, Dendroctonus pseudotsugae pseudotsugae Hopkins, occurs north of Mexico. The description of D. p. barragani was based on the only known Mexican population at that time. More recently, new populations of this beetle have been discovered at 13 additional localities in Chihuahua, Durango, Coahuila, and Nuevo Leon, Mexico. To test whether these additional populations support the existence of two subspecies, we performed a taxonomic reassessment combining molecular markers (cytochrome oxidase I), morphological characters used in the original description, and newly described morphological characters. Phylogenetic analysis of 89 haplotypes confirms that the Mexican populations are distinct from the sampled populations in the United States and Canada. Morphological analysis indicates that intraspecific variation is greater than previously considered within Mexican populations. However, at least seven characters on the head, pronotum, and elytra (including three previously undescribed characters of frons sculpture) consistently discriminate among Canada—U.S. and Mexico populations. The extension of the known distribution of this beetle in Mexico and verification of its subspecific status will aid in the management and conservation of Pseudotsuga in Mexico.
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effect of geographic isolation on genetic differentiation in Dendroctonus pseudotsugae coleoptera curculionidae
Hereditas, 2009Co-Authors: Enrico A Ruiz, John E Rinehart, Jane L Hayes, Gerardo ZunigaAbstract:Genetic structure of phytophagous insects has been widely studied, however, relative influence of the effect of geographic isolation, the host plant or both has been subject of considerable debate. Several studies carried out on bark beetles in the genus Dendroctonus evaluated these factors; nonetheless, recent evidence has shown that genetic structuring is a more complex process. Our goal was to examine the effect of geographic isolation on genetic structure of the Douglas-fir beetle Dendroctonus pseudotsugae. We used mtDNA cytochrome oxidase I (COI) sequences and RAPD markers. One hundred-seventy-two individuals were obtained from 17 populations, for which we analyzed 60 haplotypes (among 172 sequences of COI gene, 550 bp long) and 232 RAPD markers (7 primers). Analyses of molecular variance (AMOVA and SAMOVA), F-statistics and linear regressions suggest that the genetic structure of D. pseudotsugae is strongly influenced by geographic distance. We found that D. pseudotsugae has high intra- and inter-population genetic variation compared with several other bark beetles. Genetic differences among populations based on COI and RAPD markers were correlated with geographic distance. The observed genetic differences between northern (Canada-USA) and southern (Mexico) populations on Pseudotsuga menziesii var. glauca confirm that these two sets of populations correspond to previously assigned subspecies.
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phylogeographic analysis of the douglas fir beetle Dendroctonus pseudotsugae hopkins coleoptera curculionidae scolytinae
In: Bentz Barbara; Cognato Anthony; Raffa Kenneth eds. Proceedings from the Third Workshop on Genetics of Bark Beetles and Associated Microorganisms. , 2007Co-Authors: Enrico A Ruiz, John E Rinehart, Jane L Hayes, Gerardo ZunigaAbstract:Population genetic structure studies made in genus Dendroctonus have been conducted from the perspectives of allopatric and sympatric models. In the first case, host effect and historical contingency were not recognized as a source of variation, while the later considered the host itself as a source of reproductive isolation. Nevertheless, both models show that genus Dendroctonus has the highest values of genetic variation among Scolytidae (Anderson and others 1979; Anderson and others 1983; Higby and Stock 1982; Langor and Spence 1991; Namkoong and others 1979; Roberds and others 1987; Stock and Guenther 1979; Stock and others 1979; Sturgeon and Mitton 1986; Zuniga and others, in press). In this sense, few studies have been performed dealing with genetic population differences in D. pseudotsugae. For instance, through the use of Isozymes produced by 13 gene loci, Stock and others (1979) found a pattern characteristic of populations differentiated to, or beyond, the race or subspecies level between Idaho and Oregon populations. This was a consistent result in later works (Bentz and Stock 1986). However, none of these works performed a population genetic structure analysis.
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Anatomical and Histological Comparison of the Alimentary Canal of Dendroctonus micans, D. ponderosae, D. pseudotsugae pseudotsugae, D. rufipennis, and D. terebrans (Coleoptera: Scolytidae)
Annals of the Entomological Society of America, 2003Co-Authors: Elba Díaz, Olga Arciniega, Laura Sánchez, Ramón Cisneros, Gerardo ZunigaAbstract:The anatomy and histology of the alimentary canal of Dendroctonus micans (Kugelann), Dendroctonus ponderosae Hopkins, Dendroctonus pseudotsugae pseudotsugae Hopkins, Dendroctonus rufipennis (Kirby), and D. terebrans (Olivier) were described and compared. Characteristics in the structural organization of the alimentary canal in these species are comparable with those in previously studied Dendroctonus species. However, important histological differences not found in other scolytids were observed in the esophagus, crop, proventriculus, midgut, and hindgut of these species. Particularly, spines in the esophagus and crop, chitinous plates in the proventriculus, great cellular diversity in the midgut, and fine spines located in the cuticle surrounding the hindgut valve in the anterior hindgut are unique characteristics of Dendroctonus species. In the species studied, the ratio of foregut, midgut, and hindgut in relation to the total length of the alimentary canal varied slightly. This ratio did not show a relationship with insect size. Differences among the diameters of each gut region were statistically significant (P < 0.05), and the largest diameters did not necessarily appear in the largest species.