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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: M 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: M 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.
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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variation in the susceptibility of the forest Tent Caterpillar lepidoptera lasiocampidae to bacillus thuringiensis variety kurstaki hd 1 effect of the host plant
Journal of Economic Entomology, 2001Co-Authors: K C Kouassi, Francois Lorenzetti, Claude Guertin, Jean Cabana, Yves MauffetteAbstract:Host-mediated effect on the efficacy of Bacillus thuringiensis Berliner against larvae of the forest Tent Caterpillar, Malacosoma disstria Hubner, was investigated under controlled conditions. Host plants used in this study were quaking aspen, Populus tremuloides Michx., a preferred host, and sugar maple, Acer saccharum Marsh., a secondary host. Larvae were reared in the laboratory on leaves of these hosts, and upon reaching the third, fourth, and fifth instar, they were fed leaves treated with one of a range of concentrations of B. thuringiensis variety kurstaki HD-1 suspensions. Larvae were tested on the host on which they were feeding before the 4-d bioassays. The estimated LC50s were 100-fold greater on quaking aspen than on sugar maple. Also, there was a decrease in efficacy over the whole ranges of concentrations with larval age on both hosts. LC50s varied approximately two-fold between third and fifth instar. These results indicate that host-mediated effects on B. thuringiensis efficacy warrant more interest. In particular, they strongly indicate that the host plant modifies the interaction between B. thuringiensis and a target insect, and offer the opportunity to investigate the mechanism(s) that may be involved in the enhancement of B. thuringiensis toxicity.
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forest edge effects on the biological performance of the forest Tent Caterpillar lepidoptera lasiocampidae in sugar maple stands
Ecoscience, 2001Co-Authors: Michel Fortin, Yves MauffetteAbstract:Fragmentation of forests has considerably increased the amount of edge habitats. This edge effect could have a direct influence on the dynamics of forest insects by altering the nutritional quality of foliage. In this study, we examined from 1994 to 1997 the effects of foliage from edge trees and interior trees on biological performance of the forest Tent Caterpillar (Malacosoma disstria Hbn.). Each year, ten mature sugar maple trees (Acer saccharum Marsh.) were selected at the forest edge and in the forest interior. Leaves were collected on branches located at 3-6 m above ground at intervals of one or two days. These leaves were immediately brought back to the laboratory for rearing of insects in Petri dishes (8 larvae/Petri dish) and for chemical analyses. Total nitrogen levels were significantly higher in leaves from edge trees as were nonsignificantly higher levels of soluble sugars and total phenolics and lower water conTent. Generally, performance of the forest Tent Caterpillar, except for larval an...
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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, P 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.
M M Abouzaid - 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: M 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: M 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.
B V Helson - 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: M 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: M 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.
Michel Fortin - 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 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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forest edge effects on the biological performance of the forest Tent Caterpillar lepidoptera lasiocampidae in sugar maple stands
Ecoscience, 2001Co-Authors: Michel Fortin, Yves MauffetteAbstract:Fragmentation of forests has considerably increased the amount of edge habitats. This edge effect could have a direct influence on the dynamics of forest insects by altering the nutritional quality of foliage. In this study, we examined from 1994 to 1997 the effects of foliage from edge trees and interior trees on biological performance of the forest Tent Caterpillar (Malacosoma disstria Hbn.). Each year, ten mature sugar maple trees (Acer saccharum Marsh.) were selected at the forest edge and in the forest interior. Leaves were collected on branches located at 3-6 m above ground at intervals of one or two days. These leaves were immediately brought back to the laboratory for rearing of insects in Petri dishes (8 larvae/Petri dish) and for chemical analyses. Total nitrogen levels were significantly higher in leaves from edge trees as were nonsignificantly higher levels of soluble sugars and total phenolics and lower water conTent. Generally, performance of the forest Tent Caterpillar, except for larval an...
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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, P 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.
