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Darrell W Ross - One of the best experts on this subject based on the ideXlab platform.
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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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pathogenicity to Douglas Fir of ophiostoma pseudotsugae and leptographium abietinum fungi associated with the Douglas Fir beetle
Canadian Journal of Forest Research, 1997Co-Authors: Darrell W Ross, Halvor SolheimAbstract:Pole-size Douglas-Fir (Pseudotsuga menziesii (Mirb.) Franco) were inoculated with two fungi (Ophiostoma pseudotsugae (Rumb.) von Arx and Leptographium abietinum (Peck) Wingf.) associated with the Douglas-Fir beetle (Dendroctonus pseudotsugae Hopkins) to evaluate their pathogenicity. Pruning the lowermost 30% of the live crown had no effect on host tree defenses. Inoculation with O. pseudotsugae produced significantly longer lesions in the phloem and resulted in a significantly greater percentage of necrotic phloem than inoculation with L. abietinum. The percentage of occluded sapwood was also greater following O. pseudotsugae inoculations, but the difference was not statistically significant. Individual lesion lengths declined significantly with increasing inoculation density, but the total percentage of necrotic phloem increased significantly. Both fungi appeared to be better adapted to grow in sapwood than in phloem. None of the inoculated trees were dead after 5 months, but some were chlorotic with less than 30% functional sapwood within the inoculation band. The results suggest that these fungi may assist the Douglas-Fir beetle in overcoming the defenses of live trees. Resume : Des Douglas taxifoliOs (Pseudotsuga menziesii (Mirb.) Franco) au stade de perchis ont OtO inoculOs avec deux champignons, Ophiostoma pseudotsugae (Rumb.) von Arx et Leptographium abietinum (Peck) Wingf., associOs au dendroctone du Douglas taxifoliO (Dendroctonus pseudotsugae Hopkins) dans le but diOvaluer leur pathogOnOcitO. Le fait diOlaguer 30% de la cime dans sa partie infOrieure niavait pas dieffet sur les rOactions de dOfense de lihUte. Liinoculation avec O. pseudotsugae a causO des lOsions significativement plus longues dans le phlome et un pourcentage significativement plus OlevO de phlome nOcrotique quiavec L. abietinum. Le pourcentage de bois diaubier obstruO Otait Ogalement plus OlevO dans le cas des inoculations avec O. pseudotsugae mais la diffOrence niOtait pas statistiquement significative. La longueur des lOsions diminuait significativement avec liaugmentation de la densitO des inoculations mais le pourcentage total de phlome nOcrotique augmentait de faAon significative. Les deux champignons semblaient mieux adaptOs pour se dOvelopper dans le bois diaubier que dans le phlome. Aucun des arbres inoculOs niOtait mort aprs 5 mois mais certains Otaient chlorosOs et avaient moins de 30% de bois diaubier fonctionnel dans la zone diinoculation. Les rOsultats suggrent que ces champignons pourraient aider le dendroctone du Douglas taxifoliO ‡ surmonter les dOfenses des arbres vivants. (Traduit par la ROdaction)
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EFFICACY OF AN ANTIAGGREGATION PHEROMONE FOR REDUCING Douglas-Fir BEETLE, DENDROCTONUS PSEUDOTSUGAE HOPKINS (COLEOPTERA: SCOLYTIDAE), INFESTATION IN HIGH RISK STANDS
Canadian Entomologist, 1995Co-Authors: Darrell W Ross, Gary E DatermanAbstract:The Douglas-Fir beetle ( Dendroctonus pseudotsugae ) antiaggregation pheromone, 3-methylcyclohex-2-en-1-one (MCH), was applied to stands at high risk for infestation. The MCH was applied in a bubble capsule formulation to plots ranging from 2.1 to 2.6 ha in size at rates of 45–76 g/ha. Catches of Douglas-Fir beetles in attractant-baited Lindgren funnel traps located at the plot centers were significantly lower on MCH-treated plots compared with untreated plots. In contrast, catches of the most abundant predator, Thanasimus undatulus (Say), were unaffected by the MCH treatment. The percentage of Douglas-Fir [ Pseudotsuga menziesii (Mirb.) Franco] trees ≥20 cm dbh that were mass attacked was significantly lower on treated plots (0.2%) compared with untreated plots (8.5%). MCH alone was effective in reducing the probability of Douglas-Fir beetle infestations occurring in high risk stands.
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reduction of Douglas Fir beetle infestation of high risk stands by antiaggregation and aggregation pheromones
Canadian Journal of Forest Research, 1994Co-Authors: Darrell W Ross, Gary E DatermanAbstract:A combination of antiaggregation and aggregation pheromones was tested for protecting stands of Douglas-Fir (Pseudotsugamenziesii (Mirb.) Franco) at high risk for infestation by the Douglas-Fir beetle (Dendroctonuspseudotsugae Hopkins). The antiaggregation pheromone, 3-methylcyclohex-2-en-1-one (MCH), was applied in a bubble capsule formulation to the perimeter of 1-ha circular plots at a rate of 60 g/plot. Treated plots also had three or four clusters of four Lindgren funnel traps baited with frontalin, seudenol, 1-methylcyclohex-2-en-1-ol, and ethanol located outside of the plot but within 160 m of the boundary. Mean (±SE) accumulated catches in all traps per plot were 73 658 ± 19 721 Douglas-Fir beetles and 12 892 ± 2 513 Thanasimusundatulus (Say), a predator of the Douglas-Fir beetle. The mean percentage of Douglas-Fir trees ≥20 cm DBH that were mass attacked was reduced by 80% within the treated plots compared with the untreated plots. However, there was an eightfold increase in the percentage of tre...
Arne Pommerening - One of the best experts on this subject based on the ideXlab platform.
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can Douglas Fir pseudotsuga menziesii mirb franco sustainably grow in complex forest structures
Forest Ecology and Management, 2013Co-Authors: Jeanphilippe Schutz, Arne PommereningAbstract:Abstract The sustainability of shade-intermediate tree species such as Douglas Fir in complex forest structures (with more than two distinct storeys) has been controversially discussed for a long time and traditionally shade-tolerant tree species have been preferred in plenter forest management. The most critical question in this context is whether recruitment trees of a particular species can survive in the shady conditions of the understorey and whether they can contribute to a demographic continuity. Using data from the unique, replicated monitoring site Artist’s Wood in North Wales (UK) we investigated the recruitment dynamics of Douglas Fir to address the question whether this species can grow in complex forest structures on a long-term basis. Then we compared the results with those from Norway spruce and silver Fir plenter forests in the Swiss Jura. Demographic continuity in complex structures is ensured if all forest development stages are represented in appropriate demographic proportions. We quantified these development stages in terms of stem diameter classes and analysed the corresponding diameter growth, competition and the loss of trees due to mortality and forest management. Based on this analysis we determined demographic equilibrium conditions for Artist’s Wood. The results conFirmed that Douglas Fir at Artist’s Wood can indeed grow sustainably in complex forest structures at a stand density of 27.4 m 2 ha −1 basal area which corresponds to a standing volume of 342 m 3 ha −1 . However, equilibrium conditions for Douglas Fir can only be achieved at the expense of a lower overall stand density of approximately 85% of that of Norway spruce. Despite this the corresponding Douglas Fir stand volume increment of 15.3 m 3 ha −1 year −1 is greater than that of Norway spruce. Thus Douglas Fir plenter forests are not only possible but are also appealing considering the broad site amplitude of the species in conjunction with ongoing climate change and the potential of the species for CO 2 retention.
Daniel T. Schwartz - One of the best experts on this subject based on the ideXlab platform.
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Douglas Fir extractives inhibit saccharification
Bioresource Technology Reports, 2019Co-Authors: Karl R. Oleson, Daniel T. SchwartzAbstract:Abstract Phytochemical extractives can include hundreds of molecules in diverse classes—including soluble components such as flavonoids, proanthocyanidins, and terpenes—and they make-up several percent of the non-carbohydrate dry mass in small diameter Douglas-Fir forestry residues. We establish that aqueous extracts from the most extractive rich tissue of Douglas-Fir, bark, are inhibitory at biofuel relevant concentrations and demonstrate the inhibition with initial rate saccharification experiments using Trichoderma reesei cellulases. Initial rates of carbohydrate production from crystalline cellulose and amorphous cellulose substrates suggest that exoglucanase, endoglucanase and β-glucosidases are each inhibited between 15 and 25% in the presence of bark extracts. We find that despite the chemical complexity of this feedstock, the bulk of the inhibition comes from tannins while other suspicious extractive components we tested produced no statistically significant inhibition (in conditions of up to 3 grams per liter dry extractives).
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Inhibition of the Exoglucanase Cel7A by a Douglas-Fir-Condensed Tannin
2018Co-Authors: Karl R. Oleson, Kayla G. Sprenger, Jim Pfaendtner, Daniel T. SchwartzAbstract:Douglas-Fir forestry residues are a potential feedstock for saccharification-based biofuels, and condensed tannins are expected to make up ∼3% of the dry mass of this feedstock. Condensed tannins are well-known for their ability to interact with proteins and can bind and inhibit cellulase enzymes used in saccharification. In this study, we use molecular docking and classical molecular dynamics simulations to investigate how a characterized condensed tannin from Douglas-Fir bark binds to the exoglucanase Cel7A from Trichoderma reesei. Through looking at the “occupancy” and “residency” of specific amino acid residue–tannin interactions, we find that the binding sites are characterized by many simultaneous tannin–enzyme interactions with the strongest occurring on the catalytic module as opposed to the carbohydrate-binding module. The simulations indicate that tannin inhibition can result from binding at or near the catalytic tunnel’s entrance and exit. The analyzed tannin further prefers to bind to loops around the catalytic region and has affinity for aromatic and charged amino acid residues. These insights provide direction for the rational design of tannin-resistant cellulases
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Inhibition of the Exoglucanase Cel7A by a Douglas-Fir-Condensed Tannin
The Journal of Physical Chemistry, 2018Co-Authors: Karl R. Oleson, Kayla G. Sprenger, Jim Pfaendtner, Daniel T. SchwartzAbstract:Douglas-Fir forestry residues are a potential feedstock for saccharification-based biofuels, and condensed tannins are expected to make up ∼3% of the dry mass of this feedstock. Condensed tannins are well-known for their ability to interact with proteins and can bind and inhibit cellulase enzymes used in saccharification. In this study, we use molecular docking and classical molecular dynamics simulations to investigate how a characterized condensed tannin from Douglas-Fir bark binds to the exoglucanase Cel7A from Trichoderma reesei. Through looking at the “occupancy” and “residency” of specific amino acid residue–tannin interactions, we find that the binding sites are characterized by many simultaneous tannin–enzyme interactions with the strongest occurring on the catalytic module as opposed to the carbohydrate-binding module. The simulations indicate that tannin inhibition can result from binding at or near the catalytic tunnel’s entrance and exit. The analyzed tannin further prefers to bind to loops around the catalytic region and has affinity for aromatic and charged amino acid residues. These insights provide direction for the rational design of tannin-resistant cellulases.
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Extractives in Douglas-Fir forestry residue and considerations for biofuel production
Phytochemistry Reviews, 2015Co-Authors: Karl R. Oleson, Daniel T. SchwartzAbstract:Forestry residues are a plentiful, low environmental impact feedstock for biofuels and bioproducts. Douglas-Fir is the most prevalent tree species in the timberlands of western North America, with approximately 5 million tons of sustainably harvestable forestry residues available each year. These forestry residues are an important potential biomass feedstock containing holocellulose, lignin, protein, ash, and phytochemicals commonly identified as “extractives”. The phytochemical extractive category make up 5–25 % of the dry weight for different tissues of Douglas-Fir, but are rarely represented with molecular detail in feedstock models of residues for biofuel or other bioproduct. These extractives contain both primary and secondary metabolites and represent potential revenue sources as side products from processing, but also includes species that are astringent, toxic, endocrine disruptors and/or reactive in similar chemical processes. Within the “extractives” category are phytochemicals such as proanthocyanidins, phlobaphenes, waxes, flavonoids, terpenoids, phytosterols, lignans and many more. This review First identifies phytochemical molecules found in different Douglas-Fir tissues, then quantities these by category and individual molecular species, to the extent allowed by the literature. We combine the literature into a quantitative, molecularly detailed, mass conserving model for a particular Douglas-Fir forestry residue (“slash”). This model is used in a sulfite/bisulfite biofuel process simulation for understanding the molecular partitioning of extractives in different process streams. Model results are used to explore some implications for extractive species in the production of sugars and waste products from Douglas-Fir forestry residue feedstock.
Gary E Daterman - One of the best experts on this subject based on the ideXlab platform.
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EFFICACY OF AN ANTIAGGREGATION PHEROMONE FOR REDUCING Douglas-Fir BEETLE, DENDROCTONUS PSEUDOTSUGAE HOPKINS (COLEOPTERA: SCOLYTIDAE), INFESTATION IN HIGH RISK STANDS
Canadian Entomologist, 1995Co-Authors: Darrell W Ross, Gary E DatermanAbstract:The Douglas-Fir beetle ( Dendroctonus pseudotsugae ) antiaggregation pheromone, 3-methylcyclohex-2-en-1-one (MCH), was applied to stands at high risk for infestation. The MCH was applied in a bubble capsule formulation to plots ranging from 2.1 to 2.6 ha in size at rates of 45–76 g/ha. Catches of Douglas-Fir beetles in attractant-baited Lindgren funnel traps located at the plot centers were significantly lower on MCH-treated plots compared with untreated plots. In contrast, catches of the most abundant predator, Thanasimus undatulus (Say), were unaffected by the MCH treatment. The percentage of Douglas-Fir [ Pseudotsuga menziesii (Mirb.) Franco] trees ≥20 cm dbh that were mass attacked was significantly lower on treated plots (0.2%) compared with untreated plots (8.5%). MCH alone was effective in reducing the probability of Douglas-Fir beetle infestations occurring in high risk stands.
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reduction of Douglas Fir beetle infestation of high risk stands by antiaggregation and aggregation pheromones
Canadian Journal of Forest Research, 1994Co-Authors: Darrell W Ross, Gary E DatermanAbstract:A combination of antiaggregation and aggregation pheromones was tested for protecting stands of Douglas-Fir (Pseudotsugamenziesii (Mirb.) Franco) at high risk for infestation by the Douglas-Fir beetle (Dendroctonuspseudotsugae Hopkins). The antiaggregation pheromone, 3-methylcyclohex-2-en-1-one (MCH), was applied in a bubble capsule formulation to the perimeter of 1-ha circular plots at a rate of 60 g/plot. Treated plots also had three or four clusters of four Lindgren funnel traps baited with frontalin, seudenol, 1-methylcyclohex-2-en-1-ol, and ethanol located outside of the plot but within 160 m of the boundary. Mean (±SE) accumulated catches in all traps per plot were 73 658 ± 19 721 Douglas-Fir beetles and 12 892 ± 2 513 Thanasimusundatulus (Say), a predator of the Douglas-Fir beetle. The mean percentage of Douglas-Fir trees ≥20 cm DBH that were mass attacked was reduced by 80% within the treated plots compared with the untreated plots. However, there was an eightfold increase in the percentage of tre...
Glenn T Howe - One of the best experts on this subject based on the ideXlab platform.
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high density miniaturized seed orchards of Douglas Fir
New Forests, 2015Co-Authors: Scott Kolpak, Jim Smith, Michael J Albrecht, Jeff Debell, Sara Lipow, Marilyn L Cherry, Glenn T HoweAbstract:We studied miniaturized seed orchards (MSOs) and conventional orchards of coastal Douglas-Fir (Pseudotsuga menziesii var. menziesii) in a series of experiments conducted at three locations in Oregon and Washington between 2002 and 2012. In Experiment 1, cone yields were greater using stem girdles plus stem injections of GA4/7 compared to girdling alone, root pruning, and girdling plus fertilization with Ca(NO3)2. In Experiment 2, topping and pruning in the summer following flower stimulation minimized crown volume and maximized female and male flower densities. In Experiment 3, the widest spaced orchard (4 × 6 m) generally produced more flowers and cones per tree, and greater flower and cone densities compared to the narrow spaced orchards (1 × 3 and 2 × 4 m). We conclude that narrow spaced MSOs may produce more cones per hectare in the early years after establishment, but wider spaced orchards will be more productive a few years later. In general, per-hectare cone yields were similar or greater in the MSOs compared to nearby conventionally spaced orchards. Trees grafted using scions collected from juvenile trees (age 6) generally had larger crowns, more female flowers and cones per tree, and greater female flower and cone densities compared to scions collected from middle-aged (age 29) or mature (56- to 99-year-old) trees. We found no evidence that clonal rows resulted in reduced seed quality relative to nearby conventional orchards. Implications for Douglas-Fir seed orchard management are discussed.
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early genetic selection for wood stiffness in juvenile Douglas Fir and western hemlock
Forest Ecology and Management, 2014Co-Authors: Oguz S Urhan, Scott Kolpak, K J S Jayawickrama, Glenn T HoweAbstract:Wood stiffness, or modulus of elasticity (MOE), is an important property of structural wood products. The ability to genetically improve wood stiffness has increased because of the availability of tools that can measure acoustic velocity (AV, an indirect measure of MOE) on standing trees. Our goals were to optimize methods for measuring AV on young (6- to 12-year-old) Douglas-Fir and western hemlock, and then use these methods to understand the genetics of wood stiffness. In Phase I, we evaluated four standing-tree tools (TreeSonic-TS, TreeSonic-SD02, Microsecond Timer, and Ultrasonic Timer) by comparing AV2 measured on standing trees to AV2 measured on logs cut from these trees (i.e., using the HM200). We found that measuring across a whorl of branches had little adverse effect on AV measurements, and that placing the acoustic sensors on the same-face of the tree was slightly better than placing them on opposite faces. In Phase II, we used full-sib heritabilities (hfs2) to compare the TreeSonic-SD02 and Microsecond Timer, sensor orientations (same-face versus opposite-face), and flight path adjustments. Because the effect of standing-tree tool and sensor orientation was non-significant, we recommend that breeders use the TreeSonic-SD02 and same-face orientation for practical reasons. Using this approach, hfs2 for AV2 was 0.90 to 0.56 in Douglas-Fir and 0.51 in western hemlock, and we concluded that genetic gains of 7.0–17.2% can be obtained by measuring 10 or more trees per full-sib family, depending on species and seed production strategy. Because we found no strong statistical support for substantial non-additive genetic variation, the current approach of breeding for additive genetic value, and then collecting open-pollinated seed from orchards seems appropriate for improving wood stiffness. AV2 had weak genetic correlations with growth traits (height, diameter at breast height, and volume) in Douglas-Fir (−0.21 to 0.33), but moderately positive correlations in western hemlock (0.36–0.54). Therefore, there is ample opportunity to improve the stiffness of young trees without adversely affecting growth. Although mean stiffness was higher for Douglas-Fir, about 10% of the western hemlock families (7 out of 80) had higher AV2, and about 28% of the families (22 out of 80) had higher dynamic MOE than the mean for Douglas-Fir. This suggests that intensive selection and breeding in western hemlock could be used to create varieties of trees that compare favorably with unselected Douglas-Fir. This may improve the ability of western hemlock to compete with Douglas-Fir where stiffness is important.
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a snp resource for Douglas Fir de novo transcriptome assembly and snp detection and validation
BMC Genomics, 2013Co-Authors: Glenn T Howe, Scott Kolpak, Brian J Knaus, Richard Cronn, Peter C Dolan, Walter W Lorenz, Jeffrey F D DeanAbstract:Douglas-Fir (Pseudotsuga menziesii), one of the most economically and ecologically important tree species in the world, also has one of the largest tree breeding programs. Although the coastal and interior varieties of Douglas-Fir (vars. menziesii and glauca) are native to North America, the coastal variety is also widely planted for timber production in Europe, New Zealand, Australia, and Chile. Our main goal was to develop a SNP resource large enough to facilitate genomic selection in Douglas-Fir breeding programs. To accomplish this, we developed a 454-based reference transcriptome for coastal Douglas-Fir, annotated and evaluated the quality of the reference, identified putative SNPs, and then validated a sample of those SNPs using the Illumina Infinium genotyping platform. We assembled a reference transcriptome consisting of 25,002 isogroups (unique gene models) and 102,623 singletons from 2.76 million 454 and Sanger cDNA sequences from coastal Douglas-Fir. We identified 278,979 unique SNPs by mapping the 454 and Sanger sequences to the reference, and by mapping four datasets of Illumina cDNA sequences from multiple seed sources, genotypes, and tissues. The Illumina datasets represented coastal Douglas-Fir (64.00 and 13.41 million reads), interior Douglas-Fir (80.45 million reads), and a Yakima population similar to interior Douglas-Fir (8.99 million reads). We assayed 8067 SNPs on 260 trees using an Illumina Infinium SNP genotyping array. Of these SNPs, 5847 (72.5%) were called successfully and were polymorphic. Based on our validation efficiency, our SNP database may contain as many as ~200,000 true SNPs, and as many as ~69,000 SNPs that could be genotyped at ~20,000 gene loci using an Infinium II array—more SNPs than are needed to use genomic selection in tree breeding programs. Ultimately, these genomic resources will enhance Douglas-Fir breeding and allow us to better understand landscape-scale patterns of genetic variation and potential responses to climate change.
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highly variable ssr markers in Douglas Fir mendelian inheritance and map locations
Theoretical and Applied Genetics, 2004Co-Authors: Gancho T Slavov, Glenn T Howe, Igor Yakovlev, Keith J Edwards, Konstantin V Krutovskii, Gerald A Tuskan, John E Carlson, Steven H Strauss, W T AdamsAbstract:Twenty-two highly variable SSR markers were developed in Douglas-Fir [Pseudotsuga menziesii (Mirb.) Franco] from five SSR-enriched genomic libraries. Fifteen PCR primer pairs amplified a single codominant locus, while seven primer pairs occasionally amplified two loci. The Mendelian inheritance of all 22 SSRs was conFirmed via segregation analyses in several Douglas-Fir families. The mean observed heterozygosity and the mean number of alleles per locus were 0.855 (SE=0.020) and 23 (SE=1.6), respectively. Twenty markers were used in genetic linkage analysis and mapped to ten known linkage groups. Because of their high polymorphism and unambiguous phenotypes, 15 single-locus markers were selected as the most suitable for DNA fingerprinting and parentage analysis. Only three SSRs were sufficient to achieve an average probability of exclusion from paternity of 0.998 in a Douglas-Fir seed orchard block consisting of 59 parents.