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Steven G Ralph - One of the best experts on this subject based on the ideXlab platform.
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transcriptome profiles of hybrid poplar populus trichocarpa deltoides reveal rapid changes in undamaged systemic sink leaves after simulated feeding by forest tent caterpillar Malacosoma disstria
New Phytologist, 2010Co-Authors: Ryan N Philippe, Steven G Ralph, Shawn D Mansfield, Jorg BohlmannAbstract:• Poplar has been established as a model tree system for genomic research of the response to biotic stresses. This study describes a series of induced transcriptome changes and the associated physiological characterization of local and systemic responses in hybrid poplar (Populus trichocarpa × deltoides) after simulated herbivory. • Responses were measured in local source (LSo), systemic source (SSo), and systemic sink (SSi) leaves following application of forest tent caterpillar (Malacosoma disstria) oral secretions to mechanically wounded leaves. • Transcriptome analyses identified spatially and temporally dynamic, distinct patterns of local and systemic gene expression in LSo, SSo and SSi leaves. Galactinol synthase was strongly and rapidly upregulated in SSi leaves. Genome analyses and full-length cDNA cloning established an inventory of poplar galactinol synthases. Induced changes of galactinol and raffinose oligosaccharides were detected by anion-exchange high-pressure liquid chromatography. • The LSo leaves showed a rapid and strong transcriptome response compared with a weaker and slower response in adjacent SSo leaves. Surprisingly, the transcriptome response in distant, juvenile SSi leaves was faster and stronger than that observed in SSo leaves. Systemic transcriptome changes of SSi leaves have signatures of rapid change of metabolism and signaling, followed by later induction of defense genes.
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genomics of hybrid poplar populus trichocarpa deltoides interacting with forest tent caterpillars Malacosoma disstria normalized and full length cdna libraries expressed sequence tags and a cdna microarray for the study of insect induced defences in poplar
Molecular Ecology, 2006Co-Authors: Steven G Ralph, Claire Oddy, Dawn Cooper, Hesther Yueh, Ryan N Philippe, Sharon Jancsik, Natalia Kolosova, Dana Aeschliman, Richard Allen White, Dezene P W HuberAbstract:As part of a genomics strategy to characterize inducible defences against insect herbivory in poplar, we developed a comprehensive suite of functional genomics resources including cDNA libraries, expressed sequence tags (ESTs) and a cDNA microarray platform. These resources are designed to complement the existing poplar genome sequence and poplar ( Populus spp.) ESTs by focusing on herbivore- and elicitor-treated tissues and incorporating normalization methods to capture rare transcripts. From a set of 15 standard, normalized or full-length cDNA libraries, we generated 139 007 3′′ - or 5′′′ ′ -end sequenced ESTs, representing more than one-third of the c. 385 000 publicly available Populus ESTs. Clustering and assembly of 107 519 3′′ -end ESTs resulted in 14 451 contigs and 20 560 singletons, altogether representing 35 011 putative unique transcripts, or potentially more than three-quarters of the predicted c. 45 000 genes in the poplar genome. Using this EST resource, we developed a cDNA microarray containing 15 496 unique genes, which was utilized to monitor gene expression in poplar leaves in response to herbivory by forest tent caterpillars ( Malacosoma disstria ). After 24 h of feeding, 1191 genes were classified as up-regulated, compared to only 537 down-regulated. Functional classification of this induced gene set revealed genes with roles in plant defence (e.g. endochitinases, Kunitz protease inhibitors), octadecanoid and ethylene signalling (e.g. lipoxygenase, allene oxide synthase, 1-aminocyclopropane-1carboxylate oxidase), transport (e.g. ABC proteins, calreticulin), secondary metabolism [e.g. polyphenol oxidase, isoflavone reductase, (–)-germacrene D synthase] and transcriptional regulation [e.g. leucine-rich repeat transmembrane kinase, several transcription factor classes (zinc finger C3H type, AP2/EREBP, WRKY, bHLH)]. This study provides the first genome-scale approach to characterize insect-induced defences in a woody perennial providing a solid platform for functional investigation of plant–insect interactions in poplar.
J T Arnason - One of the best experts on this subject based on the ideXlab platform.
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ethyl m digallate from red maple acer rubrum l as the major resistance factor to forest tent caterpillar Malacosoma disstria hbn
Journal of Chemical Ecology, 2001Co-Authors: Mamdouh M Abouzaid, B V Helson, Constance Nozzolillo, J T ArnasonAbstract:An ethanolic extract of red maple (Acer rubrum L.) leaves (RME) applied to trembling aspen (Populus tremuloides Michx.) leaves reduced feeding in choice test assays with forest tent caterpillar larvae (Malacosoma disstria Hbn.) (FTC), whereas a trembling aspen foliage extract, similarly applied, stimulated feeding. Compounds isolated from the RME were gallic acid, methyl gallate, ethyl gallate, m-digallate, ethyl m-digallate, 1-O-galloyl-beta-D-glucose, 1-O-galloyl-alpha-L-rhamnose, kaempferol 3-O-beta-D-glucoside, kaempferol 3-O-beta-D-galactoside, kaempferol 3-O-beta-L-rhamnoside, kaempferol-3-O-rhamnoglucoside, quercetin 3-O-beta-D-glucoside, quercetin 3-O-beta-L-rhamnoside and quercetin 3-O-rhamnoglucoside, (-)-epicatechin. (+)-catechin and ellagic acid. All of the gallates, (-)-epicatechin, and kaempferol 3-O-beta-L-rhamnoside deterred feeding on trembling aspen leaf disks when applied at 0.28 mg/cm2. The two digallates deterred feeding by 90% and were the most effective. HPLC analysis indicated that ethyl m-digallate is present in amounts 10-100 x higher in RME (approximately 2.5-250 mg/g) than any other compound. Thus, ethyl m-digallate appears to be the major compound protecting red maple from feeding by FTC, with a minor contribution from other gallates.
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ethyl m digallate from red maple acer rubrum l as the major resistance factor to forest tent caterpillar Malacosoma disstria hbn
Journal of Chemical Ecology, 2001Co-Authors: Mamdouh M Abouzaid, B V Helson, Constance Nozzolillo, J T ArnasonAbstract:An ethanolic extract of red maple (Acer rubrum L.) leaves (RME) applied to trembling aspen (Populus tremuloides Michx.) leaves reduced feeding in choice test assays with forest tent caterpillar larvae (Malacosoma disstria Hbn.) (FTC), whereas a trembling aspen foliage extract, similarly applied, stimulated feeding. Compounds isolated from the RME were gallic acid, methyl gallate, ethyl gallate, m-digallate, ethyl m-digallate, 1-O-galloyl-β-D-glucose, 1-O-galloyl-α-L-rhamnose, kaempferol 3-O-β-D-glucoside, kaempferol 3-O-β-D-galactoside, kaempferol 3-O-β-L-rhamnoside, kaempferol-3-O-rhamnoglucoside, quercetin 3-O-β-D-glucoside, quercetin 3-O-β-L-rhamnoside and quercetin 3-O-rhamnoglucoside, (−)-epicatechin, (+)-catechin and ellagic acid. All of the gallates, (−)-epicatechin, and kaempferol 3-O-β-L-rhamnoside deterred feeding on trembling aspen leaf disks when applied at 0.28 mg/cm2. The two digallates deterred feeding by 90% and were the most effective. HPLC analysis indicated that ethyl m-digallate is present in amounts 10–100 × higher in RME (∼2.5–250 mg/g) than any other compound. Thus, ethyl m-digallate appears to be the major compound protecting red maple from feeding by FTC, with a minor contribution from other gallates.
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effect of host and nonhost trees on the growth and development of the forest tent caterpillar Malacosoma disstria lepidoptera lasiocampidae
Canadian Entomologist, 1997Co-Authors: R W Nicol, J T Arnason, B V Helson, M M AbouzaidAbstract:Larval growth and pupal parameters of the forest tent caterpillar ( Malacosoma disstria Hubner) reared on the foliage of two host trees ( Populus tremuloides Michx. and Acer saccharum Marsh.) and one nonhost tree ( Acer rubrum L.) were quantified. This was achieved by undertaking a larval development bioassay under controlled laboratory conditions, but using fresh leaves collected in two field seasons. Larvae fed foliage of P . tremuloides grew exponentially and began to pupate after 3 weeks. Larvae fed with A . saccharum gained significantly less weight and had a reduced number of larvae pupate, and the pupae weighed significantly less than their counterparts fed on P . tremuloides . All larvae that were fed the foliage of A . rubrum died within 2 weeks. A nutritional utilization bioassay with fourth-instar larvae revealed that the foliage of A . saccharum has a growth-inhibitory component, whereas that of A . rubrum is antifeedant. Reasons are discussed for the discrepancy between the many reports of A . saccharum being a food host for M . disstria in the field and the laboratory results.
Ryan N Philippe - One of the best experts on this subject based on the ideXlab platform.
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transcriptome profiles of hybrid poplar populus trichocarpa deltoides reveal rapid changes in undamaged systemic sink leaves after simulated feeding by forest tent caterpillar Malacosoma disstria
New Phytologist, 2010Co-Authors: Ryan N Philippe, Steven G Ralph, Shawn D Mansfield, Jorg BohlmannAbstract:• Poplar has been established as a model tree system for genomic research of the response to biotic stresses. This study describes a series of induced transcriptome changes and the associated physiological characterization of local and systemic responses in hybrid poplar (Populus trichocarpa × deltoides) after simulated herbivory. • Responses were measured in local source (LSo), systemic source (SSo), and systemic sink (SSi) leaves following application of forest tent caterpillar (Malacosoma disstria) oral secretions to mechanically wounded leaves. • Transcriptome analyses identified spatially and temporally dynamic, distinct patterns of local and systemic gene expression in LSo, SSo and SSi leaves. Galactinol synthase was strongly and rapidly upregulated in SSi leaves. Genome analyses and full-length cDNA cloning established an inventory of poplar galactinol synthases. Induced changes of galactinol and raffinose oligosaccharides were detected by anion-exchange high-pressure liquid chromatography. • The LSo leaves showed a rapid and strong transcriptome response compared with a weaker and slower response in adjacent SSo leaves. Surprisingly, the transcriptome response in distant, juvenile SSi leaves was faster and stronger than that observed in SSo leaves. Systemic transcriptome changes of SSi leaves have signatures of rapid change of metabolism and signaling, followed by later induction of defense genes.
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genomics of hybrid poplar populus trichocarpa deltoides interacting with forest tent caterpillars Malacosoma disstria normalized and full length cdna libraries expressed sequence tags and a cdna microarray for the study of insect induced defences in poplar
Molecular Ecology, 2006Co-Authors: Steven G Ralph, Claire Oddy, Dawn Cooper, Hesther Yueh, Ryan N Philippe, Sharon Jancsik, Natalia Kolosova, Dana Aeschliman, Richard Allen White, Dezene P W HuberAbstract:As part of a genomics strategy to characterize inducible defences against insect herbivory in poplar, we developed a comprehensive suite of functional genomics resources including cDNA libraries, expressed sequence tags (ESTs) and a cDNA microarray platform. These resources are designed to complement the existing poplar genome sequence and poplar ( Populus spp.) ESTs by focusing on herbivore- and elicitor-treated tissues and incorporating normalization methods to capture rare transcripts. From a set of 15 standard, normalized or full-length cDNA libraries, we generated 139 007 3′′ - or 5′′′ ′ -end sequenced ESTs, representing more than one-third of the c. 385 000 publicly available Populus ESTs. Clustering and assembly of 107 519 3′′ -end ESTs resulted in 14 451 contigs and 20 560 singletons, altogether representing 35 011 putative unique transcripts, or potentially more than three-quarters of the predicted c. 45 000 genes in the poplar genome. Using this EST resource, we developed a cDNA microarray containing 15 496 unique genes, which was utilized to monitor gene expression in poplar leaves in response to herbivory by forest tent caterpillars ( Malacosoma disstria ). After 24 h of feeding, 1191 genes were classified as up-regulated, compared to only 537 down-regulated. Functional classification of this induced gene set revealed genes with roles in plant defence (e.g. endochitinases, Kunitz protease inhibitors), octadecanoid and ethylene signalling (e.g. lipoxygenase, allene oxide synthase, 1-aminocyclopropane-1carboxylate oxidase), transport (e.g. ABC proteins, calreticulin), secondary metabolism [e.g. polyphenol oxidase, isoflavone reductase, (–)-germacrene D synthase] and transcriptional regulation [e.g. leucine-rich repeat transmembrane kinase, several transcription factor classes (zinc finger C3H type, AP2/EREBP, WRKY, bHLH)]. This study provides the first genome-scale approach to characterize insect-induced defences in a woody perennial providing a solid platform for functional investigation of plant–insect interactions in poplar.
Yves Mauffette - One of the best experts on this subject based on the ideXlab platform.
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temperature and food quality effects on growth consumption and post ingestive utilization ef ciencies of the forest tent caterpillar Malacosoma disstria lepidoptera lasiocampidae
Bulletin of Entomological Research, 2002Co-Authors: K R Levesque, M Fortin, Yves MauffetteAbstract:Temperature and food quality can both influence growth rates, consumption rates, utilization efficiencies and developmental time of herbivorous insects. Gravimetric analyses were conducted during two consecutive years to assess the effects of temperature and food quality on fourth instar larvae of the forest tent caterpillar Malacosoma disstria Hubner. Larvae were reared in the laboratory at three different temperatures (18, 24 and 30 degrees C) and on two types of diet; leaves of sugar maple trees Acer saccharum Marsh. located at the forest edge (sun-exposed leaves) or within the forest interior (shade-exposed leaves). In general, larvae reared at 18 degrees C had lower growth rates and lower consumption rates than larvae reared at the warmer temperatures (24 and 30 degrees C). Moreover, the duration of the instar decreased significantly with increasing temperatures. Type of diet also affected the growth rates and amount of food ingested by larvae but did not affect the duration of the instar. Larvae fed sun-exposed leaves consumed more food and gained higher biomasses. Values of approximate digestibility and efficiency of conversion of ingested food were also higher when larvae were fed sun-exposed leaves. Higher growth rates with increasing temperatures were primarily the result of the shorter stadium duration. The higher growth rates of larvae fed sun-exposed leaves were possibly the result of stimulatory feeding and consequently greater food intake and also a more efficient use of food ingested. This study suggests that the performance of M. disstria caterpillars could be enhanced by warmer temperatures and higher leaf quality.
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temperature and food quality effects on growth consumption and post ingestive utilization efficiencies of the forest tent caterpillar Malacosoma disstria lepidoptera lasiocampidae
International Congress of Entomology, 2002Co-Authors: K R Levesque, Michel Fortin, Yves MauffetteAbstract:Temperature and food quality can both influence growth rates, consumption rates, utilization efficiencies and developmental time of herbivorous insects. Gravimetric analyses were conducted during two consecutive years to assess the effects of temperature and food quality on fourth instar larvae of the forest tent caterpillar Malacosoma disstria Hubner. Larvae were reared in the laboratory at three different temperatures (18, 24 and 30°C) and on two types of diet; leaves of sugar maple trees Acer saccharum Marsh, located at the forest edge (sun-exposed leaves) or within the forest interior (shade-exposed leaves). In general, larvae reared at 18°C had lower growth rates and lower consumption rates than larvae reared at the warmer temperatures (24 and 30°C). Moreover, the duration of the instar decreased significantly with increasing temperatures. Type of diet also affected the growth rates and amount of food ingested by larvae but did not affect the duration of the instar. Larvae fed sun-exposed leaves consumed more food and gained higher biomasses. Values of approximate digestibility and efficiency of conversion of ingested food were also higher when larvae were fed sun-exposed leaves. Higher growth rates with increasing temperatures were primarily the result of the shorter stadium duration. The higher growth rates of larvae fed sun-exposed leaves were possibly the result of stimulatory feeding and consequently greater food intake and also a more efficient use of food ingested. This study suggests that the performance of M. disstria caterpillars could be enhanced by warmer temperatures and higher leaf quality.
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perception of aspen and sun shade sugar maple leaf soluble extracts by larvae of Malacosoma disstria
Journal of Chemical Ecology, 2001Co-Authors: M Panzuto, Francois Lorenzetti, Yves Mauffette, P J AlbertAbstract:We investigated the behavioral feeding preference and the chemoreception of leaf polar extracts from trembling aspen, Populus tremuloides, and from sun and shade sugar maple, Acer saccharum, by larvae of the polyphagous forest tent caterpillar, Malacosoma disstria, a defoliator of deciduous forests in the Northern Hemisphere. Three polar extracts were obtained from each tree species: a total extract, a water fraction, and a methanol fraction. M. disstria larvae were allowed ad libitum access to an artificial diet from eclosion to the fifth instar. Two-choice cafeteria tests were performed comparing the mean (±SE) surface area eaten of the total extracts, and the following order of preference was obtained: aspen > sun maple water fraction > total extract. Our findings are discussed in light of previously known information about this insect's performance on these host plants.
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the effects of ozone exposed sugar maple seedlings on the biological performance and the feeding preference of the forest tent caterpillar Malacosoma disstria hbn
Environmental Pollution, 1997Co-Authors: Michel Fortin, Yves Mauffette, Paul J AlbertAbstract:The effects of exposure of sugar maple (Acer saccharum Marsh.) to ozone on the entire larval stage of a native insect have not been previously investigated. This study reports the effects of sugar maple seedlings exposed to different ozone concentrations on the relative performance and the feeding preference of the forest tent caterpillar (Malacosoma disstria Hbn.). Three-year-old seedlings were set in nine open-top field chambers in the spring of 1992 and 1993. Three ozone concentrations were generated: charcoal-filtered ambient air (0x), ambient air (1x) and three times ambient air (3x). In 1992, female and male larval development time did not differ among ozone treatments. In 1993, female larvae reared on 3x developed faster than those on 0x and 1x, while male larvae were not affected. Ozone treatments did not influence pupal weights except for males in 1993 where pupae reared on 0x were heavier than 1x but did not differ from 3x. Larval and pupal survival rates were not affected by ozone in either year. Finally, 4th and 5th instar larvae showed a significant feeding preference for 3x foliage in 1993 but not in 1992. The response of the forest tent caterpillar to ozone exposed seedlings varied between years and could be more sensitive to annual climatic variations than ozone.
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The impact of ozone on the biology and the feeding preference of forest tent caterpillar (Malacosoma disstria Hbn)
1994Co-Authors: Yves Mauffette, Michel Fortin, P J AlbertAbstract:Three-year-old sugar maple seedlings were set in 9 open-top field chambers in the spring of 1992 and 1993. Three ozone concentrations were generated: charcoal-filtered ambient air (OX), ambient air concentration (1X) and 3 times ambient air concentration (3X). The aim of this study was to assess the indirect effects of sugar maple leaves exposed to different ozone concentrations on the biological performance and feeding preference of the forest tent caterpillar (Malacosoma disstria Hbn.). In 1992, the larvae reared on 1X foliage developed faster than those on 3X. In 1993, the individuals reared on 3X developed faster than those on OX, Larval survival rates in 1992 and 1993 were not affected by ozone treatments. Ozone concentrations did not influence male and female pupal weights in 1992 but they did for males in 1993 whereby insects reared on the control were larger than 1X. Finally, 4th and 5th instar larvae showed a feeding preference for 3X foliage only in 1993. These results suggest that the forest tent caterpillar response to ozone is subject to yearly variation and ozone concentration.
Hesther Yueh - One of the best experts on this subject based on the ideXlab platform.
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Blackwell Publishing LtdGenomics of hybrid poplar ( Populus trichocarpa
2015Co-Authors: Claire Oddy, Dawn Cooper, Hesther YuehAbstract:deltoides interacting with forest tent caterpillars ( Malacosoma disstria): normalized and full-length cDNA libraries, expressed sequence tags, and a cDNA microarray for the study of insect-induced defences in poplar STEVEN RALPH
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genomics of hybrid poplar populus trichocarpa deltoides interacting with forest tent caterpillars Malacosoma disstria normalized and full length cdna libraries expressed sequence tags and a cdna microarray for the study of insect induced defences in poplar
Molecular Ecology, 2006Co-Authors: Steven G Ralph, Claire Oddy, Dawn Cooper, Hesther Yueh, Ryan N Philippe, Sharon Jancsik, Natalia Kolosova, Dana Aeschliman, Richard Allen White, Dezene P W HuberAbstract:As part of a genomics strategy to characterize inducible defences against insect herbivory in poplar, we developed a comprehensive suite of functional genomics resources including cDNA libraries, expressed sequence tags (ESTs) and a cDNA microarray platform. These resources are designed to complement the existing poplar genome sequence and poplar ( Populus spp.) ESTs by focusing on herbivore- and elicitor-treated tissues and incorporating normalization methods to capture rare transcripts. From a set of 15 standard, normalized or full-length cDNA libraries, we generated 139 007 3′′ - or 5′′′ ′ -end sequenced ESTs, representing more than one-third of the c. 385 000 publicly available Populus ESTs. Clustering and assembly of 107 519 3′′ -end ESTs resulted in 14 451 contigs and 20 560 singletons, altogether representing 35 011 putative unique transcripts, or potentially more than three-quarters of the predicted c. 45 000 genes in the poplar genome. Using this EST resource, we developed a cDNA microarray containing 15 496 unique genes, which was utilized to monitor gene expression in poplar leaves in response to herbivory by forest tent caterpillars ( Malacosoma disstria ). After 24 h of feeding, 1191 genes were classified as up-regulated, compared to only 537 down-regulated. Functional classification of this induced gene set revealed genes with roles in plant defence (e.g. endochitinases, Kunitz protease inhibitors), octadecanoid and ethylene signalling (e.g. lipoxygenase, allene oxide synthase, 1-aminocyclopropane-1carboxylate oxidase), transport (e.g. ABC proteins, calreticulin), secondary metabolism [e.g. polyphenol oxidase, isoflavone reductase, (–)-germacrene D synthase] and transcriptional regulation [e.g. leucine-rich repeat transmembrane kinase, several transcription factor classes (zinc finger C3H type, AP2/EREBP, WRKY, bHLH)]. This study provides the first genome-scale approach to characterize insect-induced defences in a woody perennial providing a solid platform for functional investigation of plant–insect interactions in poplar.
