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William J Manning - One of the best experts on this subject based on the ideXlab platform.
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the first toxicological study of the Antiozonant and research tool ethylene diurea edu using a lemna minor l bioassay hints to its mode of action
Environmental Pollution, 2016Co-Authors: Eugenios Agathokleous, Elena Paoletti, Akrivichara Mouzakipaxinou, Costas J Saitanis, William J ManningAbstract:The Antiozonant and research tool ethylene diurea (EDU) is widely studied as a phytoprotectant against the widespread pollutant ground-surface ozone. Although it has been extensively used, its potential toxicity in the absence of ozone is unknown and its mode of action is unclear. The purpose of this research was to toxicologically assess EDU and to further investigate its mode of action using Lemna minor L. as a model organism. Application of EDU concentrations greater than 593 mg L(-1) (practically 600 mg L(-1)) resulted in adverse inhibition of colony growth. As no-observed-toxic-effects concentration (NOEL) we recommend a concentration of 296 mg L(-1) (practically 300 mg L(-1)). A hormetic response was detected, i.e. stimulatory effects of low EDU concentrations, which may indicate overcompensation in response to disruption in homeostasis. Growth inhibition and suppressed biomass were associated with impacted chlorophyll a fluorescence (ΦPSII, qP and ETR). Furthermore, EDU increased mesophyll thickness, as indicated by frond succulence index. Applications of concentrations ≥593 mg L(-1) to uncontrolled environments should be avoided due to potential toxicity to sensitive organisms and the environment.
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use of the Antiozonant ethylenediurea edu in italy verification of the effects of ambient ozone on crop plants and trees and investigation of edu s mode of action
Environmental Pollution, 2009Co-Authors: Elena Paoletti, William J Manning, N Contran, Anna Maria FerraraAbstract:Twenty-four experiments where EDU was used to protect plants from ozone (O(3)) in Italy are reviewed. Doses of 150 and 450 ppm EDU at 2-3 week intervals were successfully applied to alleviate O(3)-caused visible injury and growth reductions in crop and forest species respectively. EDU was mainly applied as soil drench to crops and by stem injection or infusion into trees. Visible injury was delayed and reduced but not completely. In investigations on mode of action, EDU was quickly ( 8 days), as it cannot move via phloem. EDU did not enter cells, suggesting it does not directly affect cell metabolism. EDU delayed senescence, did not affect photosynthesis and foliar nitrogen content, and stimulated antioxidant responses to O(3) exposure. Preliminary results suggest developing an effective soil application method for forest trees is warranted.
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dynamics of growth and biomass partitioning in field grown bush bean phaseolus vulgaris l treated with the Antiozonant ethylenediurea edu
Agriculture Ecosystems & Environment, 1993Co-Authors: Reinhard Kostkarick, William J ManningAbstract:Abstract The anti-ozonant ethylenediurea (EDU) approach was used to assess the effects of ambient ozone (O3) air pollution on development, growth and biomass partitioning in bush bean (Phaseolus vulgaris L. cultivar ‘BBL 290’) during five staggered plantings in 1989 and 1990. The (EDU) was applied as a soil drench twice during plant development: after unfolding of primary leaves and at early flowering. The concentration of EDU used (100 mg l−1) was considerably lower than in earlier studies, but had proven to protect bean plants from O3 injury without altering growth in previous greenhouse studies. Plants were harvested in 5 day intervals from emergence through maturity. Ambient O3 was low during the five plantings (24 h mean: 28–33 nl l−1; 7 h mean: 45–49 nl−1 O3), but number of hours and cumulative exposure > 90 nl l−1 O3 during the fifth planting was considerably higher compared with the other growth intervals. Total plant weight of EDU-treated plants fell below that of untreated plants after the second application of EDU during most of the plantings. During the fifth planting, however, total dry weight of EDU-treated plants was equal to that of untreated ones. Pod dry weight exhibited a similar pattern, and relative pod weight was reduced by EDU during late pod development in two plantings. Patterns of biomass allocation to other plant organs (foliage, stem, root) were not altered by the EDU treatments. The reduction in pod weight of EDU-treated plants was not due to a reduced number of flowers or young pods, which was actually slightly increased by the EDU treatments, but was caused by an increased rate of pod abscission during maturity. It is concluded that the second EDU soil drench was timed too early to provide protection throughout pod development and maturation. Increases in flower and bud duration and a delay in primary leaf abscission demonstrated the action of EDU in delaying maturation and senescence. From these results it is suggested that repeated soil drenches of EDU may cause reductions in the total plant weight and pod weight of a O3-sensitive bean cultivar if the exposure to ambient O3 is low. Conclusions for the further use of EDU are discussed.
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dose response studies with the Antiozonant ethylenediurea edu applied as a soil drench to two growth substrates on greenhouse grown varieties of phaseolus vulgaris l
Environmental Pollution, 1993Co-Authors: Reinhard Kostkarick, William J ManningAbstract:Abstract To study plant growth and yield effects of the Antiozonant ethylenediurea (EDU), which is frequently used for ozone crop loss assessments, dose-response studies were carried out with potted bean plants under greenhouse conditions in winter and spring. Two cultivars of Phaseolus vulgaris L., differing in sensitivity to ozone (O3), were grown in unfiltered air on a sandy loam rich in organic matter and on a vermiculite-clay mixture. Four treatments of EDU at concentrations from 300 to 800 mg liter−1 were given as a soil drench during plant development. Foliar symptoms of EDU phytoxicity were observed at all doses, and plant biomass, particularly pod dry weight, was considerably reduced to increasing doses of EDU. Primary and first trifoliate leaf weight in EDU-treated plants increased as did the number of buds, indicating an extension of vegetative growth and a delay of reproductive processes. ‘BBL 290’ beans, which are O3-sensitive, were injured by EDU more than the O3-tolerant ‘BBL 274’. The phytotoxic effects of EDU were more pronounced in the synthetic growth substrate than in field soil. In a second experiment, EDU was applied in concentrations from 100 to 400 mg liter−1 to ‘BBL 290’ plants, exposed to filtered air or simulated levels of O3 pollution. In field soil, plant growth and biomass partitioning in filtered air was only slightly altered by EDU, although leaf injury due to EDU occured. In the vermiculite-clay mix, the biomass of most plant organs, particularly that of roots, was linearly reduced with increasing EDU doses. O3 did not cause any alteration in plant biomass in field soil-grown and EDU-treated plants. Ozone leaf injury, which affected 67% of primary leaf area in non-treated plants, was completely suppressed by EDU doses as low as 100 mg liter−1. This indicates that low concentrations of EDU, which do not affect plant growth in field soil, provide sufficient protection from O3 injury. The need for careful EDU dose-response studies prior to field assessments is emphasized.
Franco Cataldo - One of the best experts on this subject based on the ideXlab platform.
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a study on the reaction between n substituted p phenylenediamines and ozone experimental results and theoretical aspects in relation to their Antiozonant activity
European Polymer Journal, 2002Co-Authors: Franco CataldoAbstract:Abstract The following p-phenylenediamines (PPD): N,N,N′,N′-tetramethyl-p-phenylenediamine (TMPPD), N,N′-dimethylbutyl-p-phenylenediamine (6PPD), N,N′-diaryl-p-phenylenediamine (DPPD), tris-(N-dimethylpentyl-p-phenylenediamine)-N′,N′,N′-1,3,5-triazine (6PPDTZ), have been oxidized under the action of O3 in diluted solutions. In all cases the radical cation or semiquinone radical was the first derivative formed by monoelectronic oxidation of the substrate. The radical cation has been studied by electronic spectroscopy and the electronic spectral changes of all mentioned PPD has been followed as function of the ozonation time. The results have been discussed in the frame of the Antiozonant properties of these PPD which are used as Antiozonant agents in diene rubber protection. It is shown that the Antiozonant activity of each PPD considered correlates with the free enthalpy of formation of the respective radical cation. The lowest is the free energy of formation of a PPD radical cation and the highest is the Antiozonant activity in a diene rubber compound.
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ozone reaction with c60 fullerene a study on the Antiozonant activity of c60 fullerene in dienic rubber
Polymer Degradation and Stability, 1995Co-Authors: Franco Cataldo, Ottorino OriAbstract:Abstract The reaction between C 60 fullerene and O 3 has been studied in CCl 4 . The ozonization reaction has been followed by UV-VIS spectroscopy and the formation of fullerene oxides C 60 O n ( n = 1,2…5) observed in the early stages of reaction as indicated by the growth of a new band at 485 nm. These oxides are formed after the scission of intermediate ozonides presumably formed. At the end of ozonization, yellowish to brown fluffy gels, insoluble in carbon tetrachloride but soluble in absolute ethanol or acetone, are recovered. They are composed of polymeric ozonides of C 60 . The UV spectrum of these substances in ethanol shows only a broad maximum at 220 nm. The dried substance examined by FT-IR spectroscopy shows extensive oxidation and fullerene cage breakdown. The tarry products are rich in keto, aldehydic and carboxylic groups. The possible Antiozonant activity of C 60 fullerene has been estimated in cis-1,4-polyisoprene. The study was conducted by measuring the viscosity change undergone by a standard solution of cis -1,4-polyisoprene in CCl 4 in the presence of C 60 without any protection, or in the presence of a commercial Antiozonant ( p -phenylenediamine-based). Contrary to expectations, the results show that cis -1,4-polyisoprene acts as an ozone scavenger and protects C 60 from ozone attack.
Reinhard Kostkarick - One of the best experts on this subject based on the ideXlab platform.
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dynamics of growth and biomass partitioning in field grown bush bean phaseolus vulgaris l treated with the Antiozonant ethylenediurea edu
Agriculture Ecosystems & Environment, 1993Co-Authors: Reinhard Kostkarick, William J ManningAbstract:Abstract The anti-ozonant ethylenediurea (EDU) approach was used to assess the effects of ambient ozone (O3) air pollution on development, growth and biomass partitioning in bush bean (Phaseolus vulgaris L. cultivar ‘BBL 290’) during five staggered plantings in 1989 and 1990. The (EDU) was applied as a soil drench twice during plant development: after unfolding of primary leaves and at early flowering. The concentration of EDU used (100 mg l−1) was considerably lower than in earlier studies, but had proven to protect bean plants from O3 injury without altering growth in previous greenhouse studies. Plants were harvested in 5 day intervals from emergence through maturity. Ambient O3 was low during the five plantings (24 h mean: 28–33 nl l−1; 7 h mean: 45–49 nl−1 O3), but number of hours and cumulative exposure > 90 nl l−1 O3 during the fifth planting was considerably higher compared with the other growth intervals. Total plant weight of EDU-treated plants fell below that of untreated plants after the second application of EDU during most of the plantings. During the fifth planting, however, total dry weight of EDU-treated plants was equal to that of untreated ones. Pod dry weight exhibited a similar pattern, and relative pod weight was reduced by EDU during late pod development in two plantings. Patterns of biomass allocation to other plant organs (foliage, stem, root) were not altered by the EDU treatments. The reduction in pod weight of EDU-treated plants was not due to a reduced number of flowers or young pods, which was actually slightly increased by the EDU treatments, but was caused by an increased rate of pod abscission during maturity. It is concluded that the second EDU soil drench was timed too early to provide protection throughout pod development and maturation. Increases in flower and bud duration and a delay in primary leaf abscission demonstrated the action of EDU in delaying maturation and senescence. From these results it is suggested that repeated soil drenches of EDU may cause reductions in the total plant weight and pod weight of a O3-sensitive bean cultivar if the exposure to ambient O3 is low. Conclusions for the further use of EDU are discussed.
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dose response studies with the Antiozonant ethylenediurea edu applied as a soil drench to two growth substrates on greenhouse grown varieties of phaseolus vulgaris l
Environmental Pollution, 1993Co-Authors: Reinhard Kostkarick, William J ManningAbstract:Abstract To study plant growth and yield effects of the Antiozonant ethylenediurea (EDU), which is frequently used for ozone crop loss assessments, dose-response studies were carried out with potted bean plants under greenhouse conditions in winter and spring. Two cultivars of Phaseolus vulgaris L., differing in sensitivity to ozone (O3), were grown in unfiltered air on a sandy loam rich in organic matter and on a vermiculite-clay mixture. Four treatments of EDU at concentrations from 300 to 800 mg liter−1 were given as a soil drench during plant development. Foliar symptoms of EDU phytoxicity were observed at all doses, and plant biomass, particularly pod dry weight, was considerably reduced to increasing doses of EDU. Primary and first trifoliate leaf weight in EDU-treated plants increased as did the number of buds, indicating an extension of vegetative growth and a delay of reproductive processes. ‘BBL 290’ beans, which are O3-sensitive, were injured by EDU more than the O3-tolerant ‘BBL 274’. The phytotoxic effects of EDU were more pronounced in the synthetic growth substrate than in field soil. In a second experiment, EDU was applied in concentrations from 100 to 400 mg liter−1 to ‘BBL 290’ plants, exposed to filtered air or simulated levels of O3 pollution. In field soil, plant growth and biomass partitioning in filtered air was only slightly altered by EDU, although leaf injury due to EDU occured. In the vermiculite-clay mix, the biomass of most plant organs, particularly that of roots, was linearly reduced with increasing EDU doses. O3 did not cause any alteration in plant biomass in field soil-grown and EDU-treated plants. Ozone leaf injury, which affected 67% of primary leaf area in non-treated plants, was completely suppressed by EDU doses as low as 100 mg liter−1. This indicates that low concentrations of EDU, which do not affect plant growth in field soil, provide sufficient protection from O3 injury. The need for careful EDU dose-response studies prior to field assessments is emphasized.
Ottorino Ori - One of the best experts on this subject based on the ideXlab platform.
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ozone reaction with c60 fullerene a study on the Antiozonant activity of c60 fullerene in dienic rubber
Polymer Degradation and Stability, 1995Co-Authors: Franco Cataldo, Ottorino OriAbstract:Abstract The reaction between C 60 fullerene and O 3 has been studied in CCl 4 . The ozonization reaction has been followed by UV-VIS spectroscopy and the formation of fullerene oxides C 60 O n ( n = 1,2…5) observed in the early stages of reaction as indicated by the growth of a new band at 485 nm. These oxides are formed after the scission of intermediate ozonides presumably formed. At the end of ozonization, yellowish to brown fluffy gels, insoluble in carbon tetrachloride but soluble in absolute ethanol or acetone, are recovered. They are composed of polymeric ozonides of C 60 . The UV spectrum of these substances in ethanol shows only a broad maximum at 220 nm. The dried substance examined by FT-IR spectroscopy shows extensive oxidation and fullerene cage breakdown. The tarry products are rich in keto, aldehydic and carboxylic groups. The possible Antiozonant activity of C 60 fullerene has been estimated in cis-1,4-polyisoprene. The study was conducted by measuring the viscosity change undergone by a standard solution of cis -1,4-polyisoprene in CCl 4 in the presence of C 60 without any protection, or in the presence of a commercial Antiozonant ( p -phenylenediamine-based). Contrary to expectations, the results show that cis -1,4-polyisoprene acts as an ozone scavenger and protects C 60 from ozone attack.
Elena Paoletti - One of the best experts on this subject based on the ideXlab platform.
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the first toxicological study of the Antiozonant and research tool ethylene diurea edu using a lemna minor l bioassay hints to its mode of action
Environmental Pollution, 2016Co-Authors: Eugenios Agathokleous, Elena Paoletti, Akrivichara Mouzakipaxinou, Costas J Saitanis, William J ManningAbstract:The Antiozonant and research tool ethylene diurea (EDU) is widely studied as a phytoprotectant against the widespread pollutant ground-surface ozone. Although it has been extensively used, its potential toxicity in the absence of ozone is unknown and its mode of action is unclear. The purpose of this research was to toxicologically assess EDU and to further investigate its mode of action using Lemna minor L. as a model organism. Application of EDU concentrations greater than 593 mg L(-1) (practically 600 mg L(-1)) resulted in adverse inhibition of colony growth. As no-observed-toxic-effects concentration (NOEL) we recommend a concentration of 296 mg L(-1) (practically 300 mg L(-1)). A hormetic response was detected, i.e. stimulatory effects of low EDU concentrations, which may indicate overcompensation in response to disruption in homeostasis. Growth inhibition and suppressed biomass were associated with impacted chlorophyll a fluorescence (ΦPSII, qP and ETR). Furthermore, EDU increased mesophyll thickness, as indicated by frond succulence index. Applications of concentrations ≥593 mg L(-1) to uncontrolled environments should be avoided due to potential toxicity to sensitive organisms and the environment.
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mycorrhizal status of an ozone sensitive poplar clone treated with the Antiozonant ethylene diurea
European Journal of Forest Research, 2014Co-Authors: Marina Katanic, Elena Paoletti, Sasa Orlovic, Tine Grebenc, Hojka KraigherAbstract:The Antiozonant ethylene diurea is proven to prevent growth reductions in forest trees induced by ozone. The community of mycorrhizal fungi could be useful indicator of environmental stress. In this study, response of mycorrhizal fungi and fine roots to a 4-year exposure to ambient ozone and treatment with Antiozonant was investigated in ozone-sensitive poplar clone under field conditions. The community of ectomycorrhizal fungi and root length colonization with ectomycorrhizal, arbuscular mycorrhizal fungi, and root endophytic fungi was analyzed in Antiozonant-treated poplar plants and in poplar plants irrigated with water. In general, plants protected by Antiozonant showed higher total number of fine roots, number of ectomycorrhizal types, Shannon–Weaver diversity index, and Species richness index compared to the plants treated with water. The ectomycorrhizal community shifted from contact exploration type in the trees irrigated with water to short-distance exploration type in ethylene diurea-treated trees. Ozone protectant may beneficially affect the belowground community of mycorrhizal fungi colonizing roots of ozone-sensitive poplar clone.
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use of the Antiozonant ethylenediurea edu in italy verification of the effects of ambient ozone on crop plants and trees and investigation of edu s mode of action
Environmental Pollution, 2009Co-Authors: Elena Paoletti, William J Manning, N Contran, Anna Maria FerraraAbstract:Twenty-four experiments where EDU was used to protect plants from ozone (O(3)) in Italy are reviewed. Doses of 150 and 450 ppm EDU at 2-3 week intervals were successfully applied to alleviate O(3)-caused visible injury and growth reductions in crop and forest species respectively. EDU was mainly applied as soil drench to crops and by stem injection or infusion into trees. Visible injury was delayed and reduced but not completely. In investigations on mode of action, EDU was quickly ( 8 days), as it cannot move via phloem. EDU did not enter cells, suggesting it does not directly affect cell metabolism. EDU delayed senescence, did not affect photosynthesis and foliar nitrogen content, and stimulated antioxidant responses to O(3) exposure. Preliminary results suggest developing an effective soil application method for forest trees is warranted.