| visualization of the cytoskeleton within the secondary vascular system of hardwood species. | a single fixation technique has been devised to demonstrate localization of alpha-tubulin (for microtubules) and f-actin (for microfilaments) within the secondary vascular system of hardwood trees by indirect immunofluorescence microscopy using butyl-methylmethacrylate-embedded material. application of this technique to problems of cytomorphogenesis during secondary growth and its versatility are demonstrated with the hardwood species aesculus hippocastanum l., salix viminalis l., s. burjatica n ... | 1997 | 9316269 |
| optical properties and nondestructive estimation of anthocyanin content in plant leaves. | absorption and reflectance spectra of maple (acer platanoides), cotoneaster (cotoneaster alaunica), dogwood (cornus alba) and pelargonium (pelargonium zonale) leaves with a wide range of pigment content and composition were studied in visible and near-infrared spectra in order to reveal specific anthocyanin (anth) spectral features in leaves. comparing absorption spectra of anth-containing and anth-free leaves with the same chlorophyll (chl) content, absorption spectra of anth in leaves were der ... | 2001 | 11460535 |
| rate of stomatal opening, shoot hydraulic conductance and photosynthetic characteristics in relation to leaf abscisic acid concentration in six temperate deciduous trees. | correlations between leaf abscisic acid concentration ([aba]), stomatal conductance (gs), rate of stomatal opening in response to an increase in leaf water potential (si), shoot hydraulic conductance (l) and photosynthetic characteristics were examined in saplings of six temperate deciduous tree species: acer platanoides l., padus avium mill., populus tremula l., quercus robur l., salix caprea l. and tilia cordata mill. species-specific values of foliar [aba] were negatively related to the mean ... | 2002 | 11874723 |
| accumulation of plant small heat-stress proteins in storage organs. | plant small heat-stress proteins (shsps) have been shown to be expressed not only after exposure to elevated temperatures, but also at particular developmental stages such as embryogenesis, microsporogenesis, and fruit maturation. this paper presents new data on the occurrence of shsps in vegetative tissues, their tissue-specific distribution, and cellular localization. we have found shsps in 1-year-old twigs of acer platanoides l. and sambucus nigra l. and in the liana aristolochia macrophylla ... | 2002 | 12029471 |
| a phagicidal and virucidal agent in maple fruit (acer platanoides l.) preparations; investigations with e. coli bacteriophage and vaccinia virus. | | 1952 | 13030206 |
| auxin and ethylene regulation of diameter growth in trees. | recent studies on the phytohormonal regulation of seasonal cell-division activity in the cambium, primary-wall radial expansion of cambial derivatives, differentiation of xylem cells, and growth of the cortex in forest trees of the north temperate zone are reviewed. indol-3-ylacetic acid (iaa, auxin) has been characterized by combined gas chromatography-mass spectrometry (gc-ms) in the cambial region of abies balsamea, pinus densiflora, pinus sylvestris and quercus robur. all of the evidence sup ... | 1988 | 14972810 |
| container-grown tree seedling responses to sodium chloride applications in different substrates. | seedlings of norway maple (acer platanoides), silver birch (betula pendula), norway spruce (picea abies) and scots pine (pinus sylvestris) were grown in selected sodium chloride (nacl) concentrations, soil types and under different watering regimes. plants were raised from seeds, except for scots pine plants which were obtained from a commercial source. among the plant species tested, scots pine was the most tolerant to soil salinity, while norway spruce was the most susceptible. for both norway ... | 2000 | 15092891 |
| biomonitoring for metal contamination near two superfund sites in woburn, massachusetts, using phytochelatins. | characterizing the spatial extent of groundwater metal contamination traditionally requires installing sampling wells, an expensive and time-consuming process in urban areas. moreover, extrapolating biotic effects from metal concentrations alone is problematic, making ecological risk assessment difficult. our study is the first to examine the use of phytochelatin measurements in tree leaves for delimiting biological metal stress in shallow, metal-contaminated groundwater systems. three tree spec ... | 2004 | 15210281 |
| tree species effects on decomposition and forest floor dynamics in a common garden. | we studied the effects of tree species on leaf litter decomposition and forest floor dynamics in a common garden experiment of 14 tree species (abies alba, acer platanoides, acer pseudoplatanus, betula pendula, carpinus betulus, fagus sylvatica, larix decidua, picea abies, pinus nigra, pinus sylvestris, pseudotsuga menziesii, quercus robur, quercus rubra, and tilia cordata) in southwestern poland. we used three simultaneous litter bag experiments to tease apart species effects on decomposition v ... | 2006 | 16995629 |
| invasion through quantitative effects: intense shade drives native decline and invasive success. | the effects of invasive nonnative species on community composition are well documented. however, few studies have determined the mechanisms by which invaders drive these changes. the literature indicates that many nonnative plant species alter light availability differently than natives in a given community, suggesting that shading may be such a mechanism. we compared light quantity (photosynthetically active radiation, par) and quality (red: far-red ratio, r:fr) in riparian reaches heavily inva ... | 2006 | 17069374 |
| larvicidal effects of various euro-asiatic plants against culex quinquefasciatus say larvae (diptera: culicidae). | extracts from 56 species of plants in the euro-asiatic region were tested for larvicidal activity against the fourth larval instar of the mosquito culex quinquefasciatus say (diptera: culicidae). all plant extracts showed larvicidal activity after 24 h of exposure to the plant extracts in a maximal dose of 500 ppm. the extracts of the plants otanthus maritimus and ammi visnaga displayed the highest larvicidal effect (ld(50) 7 and 9 ppm, respectively) followed by acer pseudoplatanus, humulus japo ... | 2008 | 18058128 |
| a glomerella species phylogenetically related to colletotrichum acutatum on norway maple in massachusetts. | a fungus isolated from norway maple (acer platanoides) in the boston, massachusetts, area was determined to be a species of glomerella, the teleomorph of colletotrin chum acutatum. pure cultures of the fungus were obtained from discharged ascospores from perithecia in leaf tissue. this fungus was determined to be homothallic based on the observation of perithecial development in cultures of single-spore isolates grown on minimal salts media and with sterile toothpicks. a morphological and molecu ... | 2008 | 18959155 |
| sapling herbivory, invertebrate herbivores and predators across a natural tree diversity gradient in germany's largest connected deciduous forest. | tree species-rich forests are hypothesised to be less susceptible to insect herbivores, but so far herbivory-diversity relationships have rarely been tested for tree saplings, and no such study has been published for deciduous forests in central europe. we expected that diverse tree communities reduce the probability of detection of host plants and increase abundance of predators, thereby reducing herbivory. we examined levels of herbivory suffered by beech (fagus sylvatica l.) and maple sapling ... | 2009 | 19238448 |
| fine root decomposition rates do not mirror those of leaf litter among temperate tree species. | elucidating the function of and patterns among plant traits above ground has been a major research focus, while the patterns and functioning of belowground traits remain less well understood. even less well known is whether species differences in leaf traits and their associated biogeochemical effects are mirrored by differences in root traits and their effects. we studied fine root decomposition and n dynamics in a common garden study of 11 temperate european and north american tree species (ab ... | 2010 | 19882174 |
| changes in photosynthetic performance and antioxidative strategies during maturation of norway maple (acer platanoides l.) leaves. | different structural and functional changes take place during leaf development. since some of them are highly connected to oxidative metabolism, regulation of reactive oxygen species (ros) abundance is required. most of the reactive oxygen species ros in plant cells are produced in chloroplasts as a result of highly energetic reactions of photosynthesis. the aim of our study was to examine the changes in concentration of oxidative stress parameters (tbars - thiobarbituric acid-reacting substance ... | 2011 | 21334907 |
| the effect of nutrient stress on developmental instability in leaves of acer platanoides (aceraceae) and betula pendula (betulaceae). | studies of developmental stability can provide insights into the amount of genetic or environmental stress experienced by individuals or populations. in the present study, we used young plants of acer platanoides (norway maple) and betula pendula (silver birch), two distantly related tree species with widely different leaf morphologies, to compare the expression of developmental instability in two contrasting environments: one with free access to nutrients and the other with a severely limited s ... | 2003 | 21659210 |
| polysaccharides from acer platanoides l. and acer pseudoplathanus l. leaves infected with rhytisma acerinum pers. as a tmv inhibitors. | | 2017 | 14211343 |
| proteomic insights into seed germination in response to environmental factors. | seed germination is a critical process in the life cycle of higher plants. during germination, the imbibed mature seed is highly sensitive to different environmental factors.however, knowledge about the molecular and physiological mechanisms underlying the environmental effects on germination has been lacking. recent proteomic work has provided invaluable insight into the molecular processes in germinating seeds of arabidopsis, rice (oryza sativa), soybean (glycine max), barley (hordeum vulgare) ... | 2013 | 23986916 |
| hypoglycin a concentrations in maple tree species in the netherlands and the occurrence of atypical myopathy in horses. | atypical myopathy (am) in horses is caused by the plant toxin hypoglycin a, which in europe typically is found in the sycamore maple tree (acer pseudoplatanus). owners are concerned about whether their horses are in danger if they graze near maple trees. | 2016 | 26995161 |
| ion-mediated enhancement of xylem hydraulic conductivity in four acer species: relationships with ecological and anatomical features. | the 'ionic effect', i.e., changes in xylem hydraulic conductivity (k(xyl)) due to variation of the ionic sap composition in vessels, was studied in four acer species growing in contrasting environments differing in water availability. hydraulic measurements of the ionic effect were performed together with measurements on the sap electrical conductivity, leaf water potential and vessel anatomy. the low ionic effect recorded in acer pseudoplatanus l. and acer campestre l. (15.8 and 14.7%, respecti ... | 2012 | 23138592 |
| inhibitory effects on bacterial growth and beta-ketoacyl-acp reductase by different species of maple leaf extracts and tannic acid. | it is important to develop new antibiotics aimed at novel targets. the investigation found that the leaf extracts from five maples (acer platanoides, acer campestre, acer rubrum, acer saccharum and acer truncatum bunge collected in denmark, canada and china) and their component tannic acid displayed antibacterial ability against 24 standard bacteria strains with the minimum inhibitory concentration of 0.3-8.0 mg/ml. unlike the standard antibiotic levofloxacin (lfx), these samples inhibited gram- ... | 2010 | 19444866 |
| probability of foliar injury for acer sp. based on foliar fluoride concentrations. | fluoride is considered one of the most phytotoxic elements to plants, and indicative fluoride injury has been associated over a wide range of foliar fluoride concentrations. the aim of this study was to determine the probability of indicative foliar fluoride injury based on acer sp. foliar fluoride concentrations using a logistic regression model. foliage from acer nedundo, acer saccharinum, acer saccharum and acer platanoides was collected along a distance gradient from three separate brick man ... | 2016 | 27878545 |
| potential tree species for use in urban areas in temperate and oceanic climates. | this study aims to assess the potential of trees for integration in urban development by evaluating the damage caused by trees in relation to various tree characteristics. tree damage to permeable pavement systems and other urban structures such as impermeable pavements, kerbs, roads, retaining walls, footpaths, walls and buildings were assessed to identify the most suitable trees for the urban environment. one hundred square sites of 100 m × 100 m were randomly selected in greater manchester fo ... | 2016 | 27699277 |
| bioaccumulation and trophodynamics of the antidepressants sertraline and fluoxetine in laboratory-constructed, 3-level aquatic food chains. | although reports of pharmaceutical bioconcentration in aquatic organisms are increasing, less is known about trophic transfer in aquatic food webs. the bioaccumulation and trophodynamics of sertraline and fluoxetine, 2 selective serotonin reuptake inhibitors (ssris) frequently detected in aquatic environments, were tested by exposing constructed aquatic food chains to ssris under controlled laboratory conditions. both of these ionizable, weak base pharmaceuticals showed lower bioaccumulation fac ... | 2017 | 27696515 |
| levels of selected trace elements in scots pine (pinus sylvestris l.), silver birch (betula pendula l.), and norway maple (acer platanoides l.) in an urbanized environment. | the aim of the study was to determine the concentrations of selected trace elements in needles and bark of scots pine (pinus sylvestris l.), leaves and bark of silver birch (betula pendula l.), and norway maple (acer platanoides l.), as well as in the soil in which the trees grew, depending on their localization and hence the distribution of local pollution sources. the content of trace elements in needles of scots pine, leaves of silver birch, and norway maple and in bark of these trees depende ... | 2016 | 27696092 |
| fine root productivity and turnover of ectomycorrhizal and arbuscular mycorrhizal tree species in a temperate broad-leaved mixed forest. | advancing our understanding of tree fine root dynamics is of high importance for tree physiology and forest biogeochemistry. in temperate broad-leaved forests, ectomycorrhizal (em) and arbuscular mycorrhizal (am) tree species often are coexisting. it is not known whether em and am trees differ systematically in fine root dynamics and belowground resource foraging strategies. we measured fine root productivity (frp) and fine root turnover (and its inverse, root longevity) of three em and three am ... | 2016 | 27617016 |
| the role of selected tree species in industrial sewage sludge/flotation tailing management. | the aim of the study was to estimate the ability of ten tree and bush species to tolerate and accumulate cd, cu, pb, zn, and as species [as(iii), as(v), and total organic arsenic] in industrial sewage sludge extremely contaminated with arsenic (almost 27.5 g kg(-1)) in a pot experiment. the premise being that it will then be possible to select the most promising tree/bush species, able to grow in the vicinity of dams where sewage sludge/flotation tailings are used as landfill. six of the ten tes ... | 2016 | 27348264 |
| linking ice accretion and crown structure: towards a model of the effect of freezing rain on tree canopies. | despite a longstanding interest in variation in tree species vulnerability to ice storm damage, quantitative analyses of the influence of crown structure on within-crown variation in ice accretion are rare. in particular, the effect of prior interception by higher branches on lower branch accumulation remains unstudied. the aim of this study was to test the hypothesis that intra-crown ice accretion can be predicted by a measure of the degree of sheltering by neighbouring branches. | 2016 | 27107412 |
| impact of interspecific competition and drought on the allocation of new assimilates in trees. | in trees, the interplay between reduced carbon assimilation and the inability to transport carbohydrates to the sites of demand under drought might be one of the mechanisms leading to carbon starvation. however, we largely lack knowledge on how drought effects on new assimilate allocation differ between species with different drought sensitivities and how these effects are modified by interspecific competition. we assessed the fate of (13) c labelled assimilates in above- and belowground plant o ... | 2016 | 27061772 |
| seasonal variability of mercury concentration in soils, buds and leaves of acer platanoides and tilia platyphyllos in central poland. | in this paper, we present the results of mercury concentration in soils, buds and leaves of maple (acer platanoides-ap) and linden (tilia platyphyllos-tp) collected in four periods of the growing season of trees, i.e. in april (iv), june (vi), august (viii) and november (ix) in 2013, from the area of poznań city (poland). the highest average concentration of mercury for 88 samples was determined in soils and it equaled 65.8 ± 41.7 ng g(-1) (range 14.5-238.9 ng g(-1)); lower average concentration ... | 2016 | 26846237 |
| assessment of heavy metal pollution in surface soils and plant material in the post-industrial city of katowice, poland. | this investigation was undertaken to assess the level of environment pollution by biological monitoring. the leaves and bark of popular ornamental trees acer pseudoplatanus l. and acer platanoides l. and soil from the sampling sites were used to perform heavy metals pollution monitoring in urban areas with different pollution sources, as well to investigate the suitability of the leaves and bark as bioindicators of pb, zn, cd and cu pollution. plant samples were collected at nine locations class ... | 2016 | 26809744 |
| seasonal variation in n uptake strategies in the understorey of a beech-dominated n-limited forest ecosystem depends on n source and species. | in forest ecosystems, species use different strategies to increase their competitive ability for nitrogen (n) acquisition. the acquisition of n by trees is regulated by tree internal and environmental factors including mycorrhizae. in this study, we investigated the n uptake strategies of three co-occurring tree species [european beech (fagus sylvatica l.), sycamore maple (acer pseudoplatanus l.) and norway maple (acer platanoides l.)] in the understorey of a beech-dominated, n-limited forest on ... | 2016 | 26786538 |
| chemometrics in biomonitoring: distribution and correlation of trace elements in tree leaves. | the concentrations of 15 elements were measured in the leaf samples of aesculus hippocastanum, tilia spp., betula pendula and acer platanoides collected in may and september of 2014 from four different locations in belgrade, serbia. the objective was to assess the chemical characterization of leaf surface and in-wax fractions, as well as the leaf tissue element content, by analyzing untreated, washed with water and washed with chloroform leaf samples, respectively. the combined approach of self- ... | 2016 | 26748000 |
| evaluation of urban environment pollution based on the accumulation of macro- and trace elements in epiphytic lichens. | nitrogen, phosphorus, potassium, magnesium, zinc, nickel, copper, manganese, iron and lead accumulation properties of three epiphytic lichen species (hypogymnia physodes (l.) nyl., parmelia sulcata taylor and xanthoria parietina (l.) th. fr.) were compared. an assessment of pollution of the municipal environment in słupsk (poland) according to macro- and trace elements was also done. lichen samples were taken in autumn 2013 from betula pendula, fraxinus excelsior, acer platanoides, a. pseudoplat ... | 2016 | 26745547 |
| clinical research abstracts of the british equine veterinary association congress 2015. | hypoglycin a (hg) appears to cause atypical myopathy (am), but to our knowledge, detection of hg in affected and unaffected horses and concurrently in plants that they were exposed to has not previously been reported. | 2015 | 26375998 |
| transpiration of urban trees and its cooling effect in a high latitude city. | an important ecosystem service provided by urban trees is the cooling effect caused by their transpiration. the aim of this study was to quantify the magnitude of daytime and night-time transpiration of common urban tree species in a high latitude city (gothenburg, sweden), to analyse the influence of weather conditions and surface permeability on the tree transpiration, and to find out whether tree transpiration contributed to daytime or nocturnal cooling. stomatal conductance and leaf transpir ... | 2016 | 26048702 |
| tree species composition affects the abundance of rowan (sorbus aucuparia l.) in urban forests in finland. | recent studies have shown a considerable increase in the abundance of rowan (sorbus aucuparia) saplings in urban forests in finland, yet the reasons for this increase are not well understood. here we investigated whether canopy cover or tree species composition, i.e., the basal areas of different tree species in norway spruce dominated urban forests, affects the abundances of rowan seedlings, saplings and trees. altogether 24 urban forest patches were investigated. we sampled the number of rowan ... | 2015 | 25588119 |
| effect of desiccation on the dynamics of genome-wide dna methylation in orthodox seeds of acer platanoides l. | 5-methylcytosine, an abundant epigenetic mark, plays an important role in the regulation of plant growth and development, but there is little information about stress-induced changes in dna methylation in seeds. in the present study, changes in a global level of m5c were measured in orthodox seeds of acer platanoides l. during seed desiccation from a wc of 1.04 to 0.05-0.06 g h2o g g(-1) dry mass (g g(-1)). changes in the level of dna methylation were measured using 2d tlc e based method. qualit ... | 2014 | 25394802 |
| proteomic analysis of embryogenesis and the acquisition of seed dormancy in norway maple (acer platanoides l.). | the proteome of zygotic embryos of acer platanoides l. was analyzed via high-resolution 2d-sds-page and ms/ms in order to: (1) identify significant physiological processes associated with embryo development; and (2) identify changes in the proteome of the embryo associated with the acquisition of seed dormancy. seventeen spots were identified as associated with morphogenesis at 10 to 13 weeks after flowering (waf). thirty-three spots were associated with maturation of the embryo at 14 to 22 waf. ... | 2014 | 24941250 |
| interacting effects of warming and drought on regeneration and early growth of acer pseudoplatanus and a. platanoides. | climate change is acting on several aspects of plant life cycles, including the sexual reproductive stage, which is considered amongst the most sensitive life-cycle phases. in temperate forests, it is expected that climate change will lead to a compositional change in community structure due to changes in the dominance of currently more abundant forest tree species. increasing our understanding of the effects of climate change on currently secondary tree species recruitment is therefore importan ... | 2015 | 24750437 |
| using sex pheromone and a multi-scale approach to predict the distribution of a rare saproxylic beetle. | the european red click beetle, elater ferrugineus l., is associated with wood mould in old hollow deciduous trees. as a result of severe habitat fragmentation caused by human disturbance, it is threatened throughout its distribution range. a new pheromone-based survey method, which is very efficient in detecting the species, was used in the present study to relate the occurrence of e. ferrugineus to the density of deciduous trees. the latter data were from a recently completed regional survey in ... | 2013 | 23840415 |
| the within-season and between-tree distribution of imidacloprid trunk-injected into acer platanoides (sapindales: sapindaceae). | norway maple trees, acer platanoides l. (sapindales: sapindaceae), that were trunk-injected with imidacloprid as part of an asian longhorned beetle eradication program, were used to study the temporal and between-tree distribution of imidacloprid in twigs from june through september. the effect of injection time during spring on imidacloprid residues across the summer season and the distribution of imidacloprid in twig bark versus twig xylem were also investigated. overall, we observed a signifi ... | 2013 | 23786077 |
| chlorophyll fluorescence kinetics, photosynthetic activity, and pigment composition of blue-shade and half-shade leaves as compared to sun and shade leaves of different trees. | the chlorophyll (chl) fluorescence induction kinetics, net photosynthetic co2 fixation rates p n, and composition of photosynthetic pigments of differently light exposed leaves of several trees were comparatively measured to determine the differences in photosynthetic activity and pigment adaptation of leaves. the functional measurements were carried out with sun, half-shade and shade leaves of seven different trees species. these were: acer platanoides l., ginkgo biloba l., fagus sylvatica l., ... | 2013 | 23670216 |
| efficacy of imidacloprid, trunk-injected into acer platanoides, for control of adult asian longhorned beetles (coleoptera: cerambycidae). | feeding experiments with asian longhorned beetles (anoplophora glabripennis (motschulsky)) in a quarantine laboratory were used to assess the effectiveness of imidacloprid in reducing adult fecundity and survival. the beetles were fed twigs and leaves cut between june-september 2010 from norway maples (acer platanoides l.) in the beetle-infested area of worcester, ma. treated trees had been trunk-injected once with imidacloprid in spring 2010 under the u.s. department of agriculture-animal and p ... | 2012 | 23356066 |
| development of the teneral adult anoplophora glabripennis (coleoptera: cerambycidae): time to initiate and completely bore out of maple wood. | anoplophora glabripennis (motschulsky) is an introduced invasive pest with the potential to devastate hardwood forests in north america. using artificial pupal chambers, we documented the time required by teneral adults at three temperatures (20, 25, and 30 °c), 60-80% rh, and a photoperiod of 16:8 (l:d) h to initiate boring after eclosion and subsequently bore completely through a 7-mm (range, 3-11 mm) layer of norway maple wood (acer platanoides l.). in total, 218 laboratory-reared pupae from ... | 2013 | 23339780 |
| colonization of three maple species by asian longhorned beetle, anoplophora glabripennis, in two mixed-hardwood forest stands. | asian longhorned beetle (alb), anoplophora glabripennis (motschulsky), is an invasive insect that has successfully established multiple times in north america. to investigate host colonization and reproductive success (exit holes/eggs), two alb infested forest stands were sampled in central massachusetts, usa. infested acer platanoides l., acer rubrum l., and acer saccharum marsh. were felled, bucked into 1 m sections and dissected to determine indications of alb infestations, such as presence o ... | 2013 | 26462582 |
| norway maple displays greater seasonal growth and phenotypic plasticity to light than native sugar maple. | norway maple (acer platanoides l), which is among the most invasive tree species in forests of eastern north america, is associated with reduced regeneration of the related native species, sugar maple (acer saccharum marsh) and other native flora. to identify traits conferring an advantage to norway maple, we grew both species through an entire growing season under simulated light regimes mimicking a closed forest understorey vs. a canopy disturbance (gap). dynamic shade-houses providing a succe ... | 2012 | 23076822 |
| plant species differences in particulate matter accumulation on leaf surfaces. | particulate matter (pm) accumulation on leaves of 22 trees and 25 shrubs was examined in test fields in norway and poland. leaf pm in different particle size fractions (pm(10), pm(2.5), pm(0.2)) differed among the species, by 10- to 15-folds at both test sites. pinus mugo and pinus sylvestris, taxus media and taxus baccata, stephanandra incisa and betula pendula were efficient species in capturing pm. less efficient species were acer platanoides, prunus avium and tilia cordata. differences among ... | 2012 | 22554531 |
| leaf litter decomposition in temperate deciduous forest stands with a decreasing fraction of beech (fagus sylvatica). | we hypothesised that the decomposition rates of leaf litter will increase along a gradient of decreasing fraction of the european beech (fagus sylvatica) and increasing tree species diversity in the generally beech-dominated central european temperate deciduous forests due to an increase in litter quality. we studied the decomposition of leaf litter including its lignin fraction in monospecific (pure beech) stands and in stands with up to five tree genera (acer spp., carpinus betulus, fagus sylv ... | 2010 | 20596729 |
| proteomic approach to analyze dormancy breaking of tree seeds. | in forest broadleaves from the temperate zone, a large number of species exhibit seed dormancy phenomena. tree seeds show some of the most pronounced and complicated forms of dormancy in the plant kingdom. many seeds are deeply physiologically dormant whatever their moisture level and age. however, dormancy can usually be overcome by a cold or warm stratification for several months. the transition from seed dormancy to germination is a multi-step process. in combination with the availability of ... | 2010 | 20306286 |
| antiprotease activity of selected slovak medicinal plants. | fifty-six methanol extracts obtained from the barks, flowers, leaves and stems of 30 slovak trees, bushes and herbs used in the traditional medicine of the small carpathians, slovakia, have been screened for antiprotease (trypsin, thrombin and urokinase) activity using chromogenic bioassay. in this study, 14 extracts showed the strong inhibition activity to protease trypsin with ic50 values below 10 microg/ml. the highest inhibition activities were observed for methanol extracts of acer platanoi ... | 2010 | 20225660 |
| optics of sunlit water drops on leaves: conditions under which sunburn is possible. | *it is a widespread belief that plants must not be watered in the midday sunshine, because water drops adhering to leaves can cause leaf burn as a result of the intense focused sunlight. the problem of light focusing by water drops on plants has never been thoroughly investigated. *here, we conducted both computational and experimental studies of this phyto-optical phenomenon in order to clarify the specific environmental conditions under which sunlit water drops can cause leaf burn. *we found t ... | 2010 | 20070538 |
| nondestructive estimation of anthocyanins and chlorophylls in anthocyanic leaves. | the anthocyanin and chlorophyll contents in leaves provide valuable information about the physiological status of plants. thus, there is a need for accurate, efficient, and practical methodologies to estimate these biochemical parameters of vegetation. in this study, we tested the performance and accuracy of several nondestructive, reflectance-based techniques for estimating anthocyanin and chlorophyll contents in leaves of four unrelated species, european hazel (corylus avellana), siberian dogw ... | 2009 | 21622307 |
| proteome analysis of norway maple (acer platanoides l.) seeds dormancy breaking and germination: influence of abscisic and gibberellic acids. | seed dormancy is controlled by the physiological or structural properties of a seed and the external conditions. it is induced as part of the genetic program of seed development and maturation. seeds with deep physiological embryo dormancy can be stimulated to germinate by a variety of treatments including cold stratification. hormonal imbalance between germination inhibitors (e.g. abscisic acid) and growth promoters (e.g. gibberellins) is the main cause of seed dormancy breaking. differences in ... | 2009 | 19413897 |
| light absorption by anthocyanins in juvenile, stressed, and senescing leaves. | the optical properties of leaves from five species, norway maple (acer platanoides l.), cotoneaster (cotoneaster alaunica golite), hazel (corylus avellana l.), siberian dogwood (cornus alba l.), and virginia creeper (parthenocissus quinquefolia (l.) planch.), differing in pigment composition and at different stages of ontogenesis, were studied. anthocyanin absorption maxima in vivo, as estimated with spectrophotometry of intact anthocyanic versus acyanic leaves and microspectrophotometry of vacu ... | 2008 | 18796701 |
| red reveals branch die-back in norway maple acer platanoides. | physiological data suggest that autumn leaf colours of deciduous trees are adaptations to environmental stress. recently, the evolution of autumn colouration has been linked to tree condition and defence. most current hypotheses presume that autumn colours vary between tree individuals. this study was designed to test if within-tree variation should be taken into account in experimental and theoretical research on autumn colouration. | 2008 | 18567914 |
| can dual chlorophyll fluorescence excitation be used to assess the variation in the content of uv-absorbing phenolic compounds in leaves of temperate tree species along a light gradient? | the present study assesses light-induced variations in phenolic compounds in leaves of saplings of two co-occurring temperate species (acer platanoides l., and fraxinus excelsior l.) along a light gradient using a new non-invasive optical method (dualex). the dualex-derived uv absorbance of leaf epidermis (the sum of the adaxial and abaxial faces, auv) increased significantly with increasing light in both species. auv values were correlated with absorbance of the leaf extract at 305 nm and 375 n ... | 2007 | 17404380 |
| copper release from chemical root-control baskets in hardwood tree production. | the city of montreal, canada, evaluated the environmental impact and usefulness of in-ground copper (cu)-treated baskets in controlling root growth of hardwood trees in nursery culture. using baskets planted with 5-yr-old norway maple (acer platanoides l.) trees, the amount and temporal pattern of cu release from the basket surface into soil was determined for two copper formulations: cu metal powder and cu(oh)2. release of both cu formulations from the basket surface decreased exponentially ove ... | 2015 | 12026095 |
| transforming echoes into pseudo-action potentials for classifying plants. | animals perceive their environment by converting sensory stimuli into action potentials, or temporal point processes, that are interpreted by the brain. this paper investigates the information content of point processes extracted from echoes from in situ plants in an effort to understand how bats recognize landmarks in the field. a mobile sonar converts echoes into biologically similar temporal point processes. termed pseudo-action potentials (paps), whose inter-pap interval relates to echo ampl ... | 2001 | 11681396 |
| ecophysiological attributes of the native acer saccharum and the exotic acer platanoides in urban oak forests in pennsylvania, usa. | when the exotic acer platanoides l. (norway maple) and the native a. saccharum marsh. (sugar maple) grow together in the understories of urban quercus forests in the eastern usa, average annual height growth increments are nearly twice as large in a. platanoides as in a. saccharum, 19.26 +/- 3.22 versus 10.01 +/- 1.69 cm. we examined several ecophysiological mechanisms that might be associated with the superior invasive ability and growth of a. platanoides in two urban oak forests in pennsylvani ... | 1995 | 14965992 |
| nuclear magnetic resonance study of spin relaxation and magnetic field gradients in maple leaves. | 1h nuclear magnetic resonance techniques were used to measure the distributions of spin-spin relaxation times, t2, and of magnetic field gradients in both the chloroplast and nonchloroplast water compartments of maple leaves (acer platanoides). results showed that encounters between water molecules and membranes inside chloroplasts provide an inefficient relaxation mechanism; i.e., chloroplast membranes interact weakly with water molecules. gradient measurements indirectly measured the sizes of ... | 1995 | 8519965 |
| combined effects of light and water stress on chloroplast volume regulation. | a nuclear magnetic resonance technique was used to measure changes in the water content of acer platanoides chloroplasts in leaf discs that had reached osmotic equilibrium with external solutions either in the dark or under exposure to light. results showed that chloroplast volume regulation (cvr) maintained constant water content in the chloroplasts over a range of water potentials in the dark, but cvr failed when the water potential fell below a critical value. the critical potential was lower ... | 1995 | 8519964 |
| in vivo study of chloroplast volume regulation. | this paper describes a new technique that can be used to study chloroplast volume regulation in vivo. nuclear magnetic resonance spectroscopy was used to measure relative amounts of chloroplast water in acer platanoides leaves as they dried in air, and also in leaf disks exposed to aqueous polyethylene glycol, sucrose, or glycerol. the chloroplasts retained a constant quantity of water as leaf water potentials varied between -0.05 and -1.90 mpa, indicating that volume regulation was effective th ... | 1992 | 1600080 |
| abscisic acid and the regulation of embryo dormancy in the genus acer. | germination of acer pseudoplatanus l. and acer platanoides l. seeds was increased by moist storage of the intact fruits (seed + pericarp) at 5 degrees c, but not at 17 degrees c. in both species, germinative capacity of isolated embryos (seeds with testa removed) was increased by moist storage of fruits at either 5 or 17 degrees c. thus dormancy loss by intact seeds and excised embryos was not necessarily correlated. loss of dormancy in isolated embryos was associated with a reduction in free ab ... | 1990 | 14972962 |
| more manganese accumulates in maple sun leaves than in shade leaves. | nuclear magnetic resonance and neutron activation analysis were used to measure manganese concentrations in leaves of acer platanoides. mn was found to accumulate in both the vacuoles and the chloroplasts, with more mn (per unit area) in sun leaves than in shade leaves. no mn was lost at senescence. different seasonal patterns of mn accumulation were found in sun and shade leaves. the quantity of chloroplast reserve mn (bound to the outer surface of thylakoid membranes) increased rapidly in sun ... | 1989 | 16666945 |
| water is allocated differently to chloroplasts in sun and shade leaves. | hydrogen-1 nuclear magnetic resonance spectroscopy was used to study water allocation in cell compartments of sun and shade leaves. nmr spectra of acer platanoides were resolved into two peaks that were assigned to chloroplast and nonchloroplast water. sun leaves contained 1.7 times more water per unit area of surface than shade leaves, and the water was allocated differently. chloroplasts in sun leaves contained 17% of the total leaf water versus 47% in shade leaves. comparing equal leaf surfac ... | 1988 | 16665860 |
| [detection of nitrogen fixing activity in the phyllosphere of plants]. | the activity of the nitrogen fixation in the phyllosphere of plants was assayed directly under the natural conditions. the highest rate of nitrogen fixation in the phylosphere was found in plants belonging to the family compositae (4.34 . 10(-1) mg n2/m2/hr) while the lowest rate was observed in acer platanoides (0.12 . 10(-1) mg n2/m2/hr), which constituted, on the average, from 0.1 to 10% of nitrogen assimilated by the plant in the course of its vital activity. the ratio between the nitrogen-f ... | 2006 | 7392985 |
| characteristics of tree bark as an indicator in high-immission areas. | in the immission area of frankfurt a.m. measurements of ph value, sulfur content and concentrations of ca(++), k(+) and na(+) of tree bark have been made. in the case of the deciduous trees fraxinus excelsior, acer platanoides and tilia spp. all parameters can be used as an indicator for the degree of immissions. even in the "desert of lichens" a division into four different zones of load is possible. because in the rhein-main area winds from the southwest predominate, the size of zones of great ... | 1977 | 28309337 |
| [information on the leaf lipids of acer platanoides l. during autumn yellowing]. | | 1967 | 6077859 |
| [constituent substances of aceraceae; bark of acer platanoides]. | | 1953 | 13133705 |