The Experts below are selected from a list of 2652 Experts worldwide ranked by ideXlab platform
Ian T. Baldwin - One of the best experts on this subject based on the ideXlab platform.
-
soil degradation slows growth and inhibits jasmonate induced resistance in Artemisia vulgaris
Ecological Applications, 2005Co-Authors: Matthias Held, Ian T. BaldwinAbstract:German reunification closed factories that produced point-source emissions and, in so doing, provided ecologists with well-defined pollution gradients with which to study the effects of plant stress on induced resistance against herbivores. We characterized a gradient of severely degraded soil from the dust emissions of a former fertilizer factory and selected three sites along this gradient to study the interaction of pollution stress and herbivore resistance in a single maternal lineage of Artemisia vulgaris that had colonized these disturbed habitats. We measured A. vulgaris growth, reproductive success, and inducible herbivore resistance by eliciting plants at each site with a quantitative methyl jasmonate (MeJA) treatment, and measured the reproductive success of two native herbivores, the aphid Macrosiphoniella Artemisiae (in the field) and the grasshopper Chorthippus mollis (in the laboratory). Soil heavy metals and phosphate contents decreased with distance from the former factory, while cation ex...
-
SOIL DEGRADATION SLOWS GROWTH AND INHIBITS JASMONATE‐INDUCED RESISTANCE IN Artemisia vulgaris
Ecological Applications, 2005Co-Authors: Matthias Held, Ian T. BaldwinAbstract:German reunification closed factories that produced point-source emissions and, in so doing, provided ecologists with well-defined pollution gradients with which to study the effects of plant stress on induced resistance against herbivores. We characterized a gradient of severely degraded soil from the dust emissions of a former fertilizer factory and selected three sites along this gradient to study the interaction of pollution stress and herbivore resistance in a single maternal lineage of Artemisia vulgaris that had colonized these disturbed habitats. We measured A. vulgaris growth, reproductive success, and inducible herbivore resistance by eliciting plants at each site with a quantitative methyl jasmonate (MeJA) treatment, and measured the reproductive success of two native herbivores, the aphid Macrosiphoniella Artemisiae (in the field) and the grasshopper Chorthippus mollis (in the laboratory). Soil heavy metals and phosphate contents decreased with distance from the former factory, while cation ex...
Matthias Held - One of the best experts on this subject based on the ideXlab platform.
-
soil degradation slows growth and inhibits jasmonate induced resistance in Artemisia vulgaris
Ecological Applications, 2005Co-Authors: Matthias Held, Ian T. BaldwinAbstract:German reunification closed factories that produced point-source emissions and, in so doing, provided ecologists with well-defined pollution gradients with which to study the effects of plant stress on induced resistance against herbivores. We characterized a gradient of severely degraded soil from the dust emissions of a former fertilizer factory and selected three sites along this gradient to study the interaction of pollution stress and herbivore resistance in a single maternal lineage of Artemisia vulgaris that had colonized these disturbed habitats. We measured A. vulgaris growth, reproductive success, and inducible herbivore resistance by eliciting plants at each site with a quantitative methyl jasmonate (MeJA) treatment, and measured the reproductive success of two native herbivores, the aphid Macrosiphoniella Artemisiae (in the field) and the grasshopper Chorthippus mollis (in the laboratory). Soil heavy metals and phosphate contents decreased with distance from the former factory, while cation ex...
-
SOIL DEGRADATION SLOWS GROWTH AND INHIBITS JASMONATE‐INDUCED RESISTANCE IN Artemisia vulgaris
Ecological Applications, 2005Co-Authors: Matthias Held, Ian T. BaldwinAbstract:German reunification closed factories that produced point-source emissions and, in so doing, provided ecologists with well-defined pollution gradients with which to study the effects of plant stress on induced resistance against herbivores. We characterized a gradient of severely degraded soil from the dust emissions of a former fertilizer factory and selected three sites along this gradient to study the interaction of pollution stress and herbivore resistance in a single maternal lineage of Artemisia vulgaris that had colonized these disturbed habitats. We measured A. vulgaris growth, reproductive success, and inducible herbivore resistance by eliciting plants at each site with a quantitative methyl jasmonate (MeJA) treatment, and measured the reproductive success of two native herbivores, the aphid Macrosiphoniella Artemisiae (in the field) and the grasshopper Chorthippus mollis (in the laboratory). Soil heavy metals and phosphate contents decreased with distance from the former factory, while cation ex...
Tristan James Mabry - One of the best experts on this subject based on the ideXlab platform.
-
Estrogenic Flavonoids from Artemisia vulgaris L.
Journal of Agricultural and Food Chemistry, 1998Co-Authors: Ha-yull Chung, Camelia G.-a. Maier, Angela R. Wood, Richard A. Dixon, Tristan James MabryAbstract:The comprehensive quantitative analysis of the flavonoid chemistry of Artemisia vulgaris L., a plant used as an emmenagogue in traditional medicine, is presented in conjunction with an evaluation of its estrogenic activity. Twenty known flavonoids were isolated and identified as tricine, jaceosidine, eupafolin, chrysoeriol, diosmetin, homoeriodictyol, isorhamnetin, apigenin, eriodictyol, luteolin, luteolin 7-glucoside, kaempferol 3-glucoside, kaempferol 7-glucoside, kaempferol 3-rhamnoside, kaempferol 3-rutinoside, quercetin 3-glucoside, quercetin 3-galactoside, quercetrin, rutin, and vitexin. The most abundant compounds were eriodictyol and luteolin. The estrogenic activity of all flavonoids was assayed by employing a reconstituted estrogen transcription unit in Saccharomyces cerevisiae transformed with both a human estrogen receptor expression plasmid and a reporter plasmid. Two flavonoids, eriodictyol and apigenin, were able to induce the transcription of the reporter gene in transgenic yeast. The transcriptional activity increased proportionally with increased amounts of purified eriodictyol or apigenin added to the yeast cells.
Dragan T. Veličković - One of the best experts on this subject based on the ideXlab platform.
-
Phenological Variations in the Surface Flavonoids of Artemisia vulgaris L. and Artemisia absinthium L.
Turkish Journal of Botany, 2007Co-Authors: Milena Nikolova, Dragan T. VeličkovićAbstract:Qualitative and quantitative variations in the surface flavonoids in relation to phenological development of Artemisia vulgaris L. and Artemisia absinthium L. were examined. Plant material was harvested at different phenological stages (vegetative, before budding, floral budding, flowering, and fruiting) of the life cycle of the species. In A. vulgaris and A. absinthium acetone exudates, 6 and 4 flavonoid aglycones were identified, respectively, by TLC analysis. Quercetin 3,7,3'-trimethyl ether is the main flavonoid in the exudates of A. vulgaris while quercetagetin 3,6,7,3',4'-pentamethyl ether is the predominant flavonoid in A. absinthium. Qualitative variations in the flavonoid composition of A. vulgaris were established. Quantification of the flavonoid aglycones shows that their content was highest in the flowering stage. During the phenological development all of the detected flavonoids in A. absinthium were synthesised but differences in their relative amounts were observed. The main flavonoid aglycones were most abundant at the budding stage.
Leslie A Weston - One of the best experts on this subject based on the ideXlab platform.
-
Isolation and characterization of allelopathic volatiles from mugwort (Artemisia vulgaris)
Journal of Chemical Ecology, 2005Co-Authors: Jacob N. Barney, Leslie A WestonAbstract:Several volatile allelochemicals were identified and characterized from fresh leaf tissue of three distinct populations of the invasive perennial weed, mugwort ( Artemisia vulgaris ). A unique bioassay was used to demonstrate the release of volatile allelochemicals from leaf tissues. Leaf volatiles were trapped and analyzed via gas chromatography coupled with mass spectrometry. Some of the components identified were terpenes, including camphor, eucalyptol, α-pinene, and β-pinene. Those commercially available were tested individually to determine their phytotoxicity. Concentrations of detectable volatiles differed in both absolute and relative proportions among the mugwort populations. The three mugwort populations consisted of a taller, highly branched population (ITH-1); a shorter, lesser-branched population (ITH-2) (both grown from rhizome fragments from managed landscapes); and a population grown from seed with lobed leaves (VT). Considerable interspecific variation existed in leaf morphology and leaf surface chemistry. Bioassays revealed that none of the individual monoterpenes could account for the observed phytotoxicity imparted by total leaf volatiles, suggesting a synergistic effect or activity of a component not tested. Despite inability to detect a single dominant phytotoxic compound, decreases in total terpene concentration with increase in leaf age correlated with decreases in phytotoxicity. The presence of bioactive terpenoids in leaf surface chemistry of younger mugwort tissue suggests a potential role for terpenoids in mugwort establishment and proliferation in introduced habitats.
-
Isolation and characterization of allelopathic volatiles from mugwort ( Artemisia vulgaris )
Journal of chemical ecology, 2005Co-Authors: Jacob N. Barney, Anthony G. Hay, Leslie A WestonAbstract:Several volatile allelochemicals were identified and characterized from fresh leaf tissue of three distinct populations of the invasive perennial weed, mugwort (Artemisia vulgaris). A unique bioassay was used to demonstrate the release of volatile allelochemicals from leaf tissues. Leaf volatiles were trapped and analyzed via gas chromatography coupled with mass spectrometry. Some of the components identified were terpenes, including camphor, eucalyptol, alpha-pinene, and beta-pinene. Those commercially available were tested individually to determine their phytotoxicity. Concentrations of detectable volatiles differed in both absolute and relative proportions among the mugwort populations. The three mugwort populations consisted of a taller, highly branched population (ITH-1); a shorter, lesser-branched population (ITH-2) (both grown from rhizome fragments from managed landscapes); and a population grown from seed with lobed leaves (VT). Considerable interspecific variation existed in leaf morphology and leaf surface chemistry. Bioassays revealed that none of the individual monoterpenes could account for the observed phytotoxicity imparted by total leaf volatiles, suggesting a synergistic effect or activity of a component not tested. Despite inability to detect a single dominant phytotoxic compound, decreases in total terpene concentration with increase in leaf age correlated with decreases in phytotoxicity. The presence of bioactive terpenoids in leaf surface chemistry of younger mugwort tissue suggests a potential role for terpenoids in mugwort establishment and proliferation in introduced habitats.