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Sample records for quercus macrocarpa leaves

  1. Light response of hydraulic conductance in bur oak (Quercus macrocarpa) leaves.

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    Voicu, Mihaela C; Zwiazek, Janusz J; Tyree, Melvin T

    2008-07-01

    A four- to seven-fold enhancement of leaf hydraulic conductance by light has been reported in three temperate tree species. The enhancement occurs in the liquid-flow pathway between the petiole and the site of water evaporation. The enhancement occurs within 1 h, and dissipates in darkness over a period of 1 to 10 h depending on species. Here we report light-induced enhancement of leaf hydraulic conductance in a fourth species, bur oak (Quercus macrocarpa Michx.), the dependence of the effect on light flux and color, its absence in leaves of seedlings, and the impact on the response of leaf vein severance and several metabolic inhibitors. The light response of leaf hydraulic conductance approached saturation at a photosynthetic photon flux of 150 mumol m(-2) s(-1). Hydraulic enhancement was greater in response to blue and green light than to visible radiation of longer wavelengths, although at the same irradiance, the response to white light was greater than to light of any single color. Atrazine (a photosystem II inhibitor), fusicoccin (which stimulates plasma membrane-bound H(+)-ATPase) and HgCl(2) (an aquaporin blocker) reduced the light response of leaf lamina hydraulic conductance. When 2-mercaptoethanol was added following mercury treatment, the light response was totally suppressed. Our results are consistent with the notion that the effect of light on leaf lamina hydraulic conductance is controlled by factors acting outside the leaf veins, possibly through light-induced changes in membrane permeability of either mesophyll or bundle sheath cells, or both.

  2. Drivers of radial growth and carbon isotope discrimination of bur oak (Quercus macrocarpa Michx.) across continental gradients in precipitation, vapour pressure deficit and irradiance

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    Steven L. Voelker; Frederick C. Meinzer; Barbara Lachenbruch; J. Renee Brooks; Richard P. Guyette

    2014-01-01

    Tree-ring characteristics are commonly used to reconstruct climate variables, but divergence from the assumption of a single biophysical control may reduce the accuracy of these reconstructions. Here, we present data from bur oaks (Quercus macrocarpa Michx.) sampled within and beyond the current species bioclimatic envelope to identify the primary...

  3. Chemical constituents and cytotoxic evaluation of essential oils from leaves of Porcelia macrocarpa (Annonaceae).

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    da Silva, Erica Biolcati P; Matsuo, Alisson L; Figueiredo, Carlos R; Chaves, Mariana H; Sartorelli, Patricia; Lago, João Henrique G

    2013-02-01

    This work reports the chemical composition and cytotoxic evaluation of the essential oils from three different samples of the leaves of Porcelia macrocarpa R. E. Fries (Annonaceae). The crude oils, obtained by hydrodistillation procedures, were chemically analyzed by GC/MS. The obtained data indicated the predominance of sesquiterpenes (89.8 +/- 0.7%), the main compounds being germacrene D (47 +/-+/- 1%) and bicyclogermacrene (37 +/- 1%). These oils also contained the monoterpene verbanyl acetate (0.5 +/- 0.06%) and the diterpene phytol (1.2 +/- 0.3%). The crude oils obtained from leaves were pooled and tested in vitro against six cancer cell lineages--murine melanoma (B16F10-Nex2), human glioblastome (U87), human cervical carcinoma (HeLa), human leukemia (HL-60), human colon carcinoma (HCT), human breast adenocarcinoma (SKBr), and human melanoma (A2058), as well as against a non-tumorigenic human cell line (HFF). Since the essential oil reduced more than 50% of the viability of several tumor cells at 100 microg/mL, indicating the presence of active compounds, the crude material was subjected to fractionation over a SiO2/AgNO3 column. This procedure afforded different fractions composed of pure as well as different mixtures of bicyclogermacrene and germacrene D, which were tested against the same tumor cell lines, indicating a significant cytotoxic potential against HL-60 cells. These results suggested that the crudeoils and their components, mainly germacrene D, could be used as prototypes for the development of new anti-cancer agents for the treatment of human leukemia.

  4. Multi-element fingerprinting and high throughput sequencing identify multiple elements that affect fungal communities in Quercus macrocarpa foliage.

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    Jumpponen, Ari; Keating, Karen; Gadbury, Gary; Jones, Kenneth L; Mattox, J David

    2010-09-01

    Diverse fungal mutualists, pathogens and saprobes colonize plant leaves. These fungi face a complex environment, in which stochastic dispersal interplays with abiotic and biotic filters. However, identification of the specific factors that drive the community assembly seems unattainable. We mined two broad data sets and identified chemical elements, to which dominant molecular operational taxonomic units (OTUs) in the foliage of a native tree respond most extremely. While many associations could be identified, potential complicating issues emerged. Those were related to unevenly distributed OTU frequency data, a large number of potentially explanatory variables, and the disproportionate effects of outlier observations.

  5. Effect of tannins from Quercus suber and Quercus coccifera leaves on ethanol-induced gastric lesions in mice.

    Science.gov (United States)

    Khennouf, Seddik; Benabdallah, Hassiba; Gharzouli, Kamel; Amira, Smain; Ito, Hideyuki; Kim, Tae-Hoon; Yoshida, Takashi; Gharzouli, Akila

    2003-02-26

    The gastroprotective effects of 70% acetone extracts of Quercus suber and Quercus coccifera leaves and of tannins (pedunculagin, castalagin, phillyraeoidin A, and acutissimin B) purified from these extracts were examined in the mouse using the ethanol-induced gastric ulcer model. Both extracts (25, 50, and 100 mg/kg), given orally, prevented the formation of ethanol-induced lesions in the stomach. The percent protection varied between 68 and 91%. Purified tannins (50 mg/kg) were also effective in protecting the stomach against ethanol, and the percent protection varied from 66 to 83%. Castalagin was the most potent. Both extracts and all of the tannins tested (10, 25, and 50 microg/mL) strongly inhibited (55-65%) the lipid peroxidation of rabbit brain homogenate. These results suggest that the gastroprotective effects of extracts of Q. suber and Q. coccifera leaves and the purified tannins in this experimental model are related to their anti-lipoperoxidant properties.

  6. Chromatogram Profiles and Cytotoxic Activity of Irradiated Mahkota Dewa (Phaleria Macrocarpa Scheff. Boerl Leaves

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    E. Katrin1

    2011-04-01

    Full Text Available Gamma irradiation has been used by the industries for preservation of herbal medicine, but it has not been studied the effect of gamma irradiation on their efficacy, especially their bioactivity as anticancer substances. The purpose of this research was to study the effect of gamma irradiation on the mahkota dewa leaves which has been claimed to contain potent anticancer substances. Maceration of dried mahkota dewa leaves successively with n-hexane, ethyl acetate, and ethanol gave crude extracts which the ethyl acetate was the most cytotoxic extract against leukemia L1210 cells with an inhibition concentration fifty (IC50 value of 10.3 µg/ml. Further separation of ethyl acetate extract by column chromatograph gave 7 fractions, and fraction 2 showed the most cytotoxic fraction exhibited the most cytotoxic extract against leukemia L1210 cells with an IC50 value of 1.9 µg/ml. Since, the fraction 2 of ethyl acetate extract was the most potent fraction, the irradiated samples were treated with the same procedure as treatment of fraction 2 from control sample. Cytotoxic activity test of fractions 2 from irradiated samples showed that the cytotoxic activity decreased depending on increasing of irradiation dose. Gamma irradiation dose up to 7.5 kGy on mahkota dewa leaves could decreased the cytotoxic activity of fraction 2 as the most cytotoxic-potential fraction against leukemia L1210 cells, but decreasing the cytotoxic activity has not exceeded the limit of the fraction declared inactive. So that the irradiation dose up to 7.5 kGy can be used for decontamination of bacteria and fungus/yeast without eliminating the cytotoxic activity. Gamma irradiation also caused changes in the thin layer chromatograph (TLC spots and HPLC chromatograms profiles of fraction 2 which was the most cytotoxic fraction in ethyl acetate extract of mahkota dewa leaves against leukemia L1210 cells. One of the main peaks (peak 1 on HPLC chromatograms decreased with increasing

  7. Water metabolism of leaves of Quercus robur in antierosion stands in the south of its range

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    V. P. Bessonova

    2016-10-01

    Full Text Available We have investigated the main parameters of water exchange in leaves of Quercus robur L. which grow on the south-facing slope of the Viyskoviy ravine in a variety of water supply conditions. We established that the greatest intensity of transpiration of leaves of Q. robur occurred in the forest vegetation conditions of SG2, the smallest in SG1–0. In all study periods the largest amplitude of daily fluctuations in intensity of transpiration occurred in leaves of plants along the talweg, at other test sites the limits were much lower. The highest rates of transpiration were in September, which is connected with the high temperatures and lower relative air humidity compared with the days of measurement in July and May. We established that at the beginning of the growing season there was no difference in the total amount of water in the leaves of the trees that grow on the middle and upper parts of the slope, but that it was greater in plants along the talweg. In the following months the difference between the water content in the leaves of trees along the talweg and upper third of the slope increased. The leaves of trees that grow in the poorest conditions of water supply were characterized by the highest water-holding capacity, which is coordinated with their containing the highest content of hydrophilic colloids. The values for water deficit in May and in July fell within the maximum fluctuations for the species studied, but in early September they exceeded the maximum value in the leaves of trees on the upper third of the slope.

  8. Biogeographic patterns of nutrient resorption from Quercus variabilis Blume leaves across China.

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    Sun, X; Kang, H; Chen, H Y H; Björn, B; Samuel, B F; Liu, C

    2016-05-01

    The variation in nutrient resorption has been studied at different taxonomic levels and geographic ranges. However, the variable traits of nutrient resorption at the individual species level across its distribution are poorly understood. We examined the variability and environmental controls of leaf nutrient resorption of Quercus variabilis, a widely distributed species of important ecological and economic value in China. The mean resorption efficiency was highest for phosphorus (P), followed by potassium (K), nitrogen (N), sulphur (S), magnesium (Mg) and carbon (C). Resorption efficiencies and proficiencies were strongly affected by climate and respective nutrients concentrations in soils and green leaves, but had little association with leaf mass per area. Climate factors, especially growing season length, were dominant drivers of nutrient resorption efficiencies, except for C, which was strongly related to green leaf C status. In contrast, green leaf nutritional status was the primary controlling factor of leaf nutrient proficiencies, except for C. Resorption efficiencies of N, P, K and S increased significantly with latitude, and were negatively related to growing season length and mean annual temperature. In turn, N, P, K and S in senesced leaves decreased with latitude, likely due to their efficient resorption response to variation in climate, but increased for Mg and did not change for C. Our results indicate that the nutrient resorption efficiency and proficiency of Q. variabilis differed strongly among nutrients, as well as growing environments. Our findings provide important insights into understanding the nutrient conservation strategy at the individual species level and its possible influence on nutrient cycling.

  9. Diurnal changes in photoprotective mechanisms in leaves of cork oak (Quercus suber) during summer.

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    Faria, T.; García-Plazaola, J. I.; Abadía, A.; Cerasoli, S.; Pereira, J. S.; Chaves, M. M.

    1996-01-01

    Daily variations in photoprotective mechanisms were studied in sun and shade leaves of 40-year-old cork oak (Quercus suber L.) trees during early summer in Portugal. Although trees were not severely water stressed because predawn leaf water potentials remained high, photosynthesis and stomatal conductance decreased at midday. The midday depression in gas exchange was not reversed by short-term exposure to "optimal" conditions of temperature, light and vapor pressure deficit. Chlorophyll a fluorescence, maximum photochemical yield of photosystem II and the quantum yield of noncyclic electron transport showed midday depressions, but recovered by the evening. Both short-term changes in the components of the xanthophyll cycle (reversible de-epoxidation of violaxanthin during the day) as well as long-term changes (higher xanthophyll content in sun compared with shade leaves) were detected and may play a role in the dissipation of excess energy at midday. Because the activities of enzymes of the antioxidant system, superoxide dismutase and ascorbate peroxidase, were high enough to cope with the increase in oxygen reactive species likely to arise under the stressful conditions of midday, we conclude that these enzymes may provide an additional mechanism for energy dissipation.

  10. Antioxidant and α-glucosidase inhibitor activities of natural compounds isolated from Quercus gilva Blume leaves

    Institute of Scientific and Technical Information of China (English)

    Anastasia Wheni Indrianingsih; Sanro Tachibana; Rizna Triana Dewi; Kazutaka Itoh

    2015-01-01

    To isolate and investigate antioxidant and α-glucosidase inhibitor compounds in the leaves of Quercus gilva Blume (Q. gilva). Methods: Dry leaves of Q. gilva were extracted with methanol and the methanolic extract was further separated by silica gel column chromatography using several solvents with increasing polarity. The antioxidant activities of the isolated compounds were evaluated using various in vitro assays: 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity, hydrogen peroxide radical scavenging activity, β-carotene bleaching assay, and reducing power assay. The α-glucosidase inhibitory assay was conducted against α-glucosidase from Saccharomyces cerevisiae. Results: Three compounds were isolated and their structures were identified as catechin (1), epicatechin (2), and tiliroside (3) using an instrumental analysis. Compound 2 had higher antioxidant activity with inhibitory concentrations (IC50) of (22.55 ± 2.23) µmol/L than that of quercetin, which was used as the standard, with an IC50 of (28.08 ± 2.39) µmol/L, followed by compound 1 with IC50 of (40.86 ± 3.45) µmol/L. On the other hand, compound 3 had the lowest antioxidant activity with an IC50 of (160.24 ± 8.15) µmol/L. However, compound 3 had the highest α-glucosidase inhibitory activity with an IC50 of (28.36 ± 0.11) µmol/L, followed by compounds 1 and 2 with (168.60 ± 5.15) and (920.60 ± 10.10) µmol/L, respectively. Conclusions: The results obtained for the antioxidant activities and α-glucosidase inhibitory activities in a methanolic extract from the leaves of Q. gilva confirmed the potential of this plant as a source of natural antioxidants and antidiabetic medicine.

  11. Antioxidant and α-glucosidase inhibitor activities of natural compounds isolated from Quercus gilva Blume leaves

    Institute of Scientific and Technical Information of China (English)

    Anastasia; Wheni; Indrianingsih; Sanro; Tachibana; Rizna; Triana; Dewi; Kazutaka; Itoh

    2015-01-01

    Objective: To isolate and investigate antioxidant and α-glucosidase inhibitor compounds in the leaves of Quercus gilva Blume(Q. gilva).Methods: Dry leaves of Q. gilva were extracted with methanol and the methanolic extract was further separated by silica gel column chromatography using several solvents with increasing polarity. The antioxidant activities of the isolated compounds were evaluated using various in vitro assays: 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity, hydrogen peroxide radical scavenging activity, β-carotene bleaching assay, and reducing power assay. The α-glucosidase inhibitory assay was conducted against α-glucosidase from Saccharomyces cerevisiae.Results: Three compounds were isolated and their structures were identii ed as catechin(1), epicatechin(2), and tiliroside(3) using an instrumental analysis. Compound 2 had higher antioxidant activity with inhibitory concentrations(IC50) of(22.55 ± 2.23) μmol/L than that of quercetin, which was used as the standard, with an IC50 of(28.08 ± 2.39) μmol/L, followed by compound 1 with IC50 of(40.86 ± 3.45) μmol/L. On the other hand, compound 3 had the lowest antioxidant activity with an IC50 of(160.24 ± 8.15) μmol/L. However, compound 3 had the highest α-glucosidase inhibitory activity with an IC50 of(28.36 ± 0.11) μmol/L, followed by compounds 1 and 2 with(168.60 ± 5.15) and(920.60 ± 10.10) μmol/L, respectively.Conclusions: The results obtained for the antioxidant activities and α-glucosidase inhibitory activities in a methanolic extract from the leaves of Q. gilva coni rmed the potential of this plant as a source of natural antioxidants and antidiabetic medicine.

  12. The bulk elastic modulus and the reversible properties of cell walls in developing Quercus leaves.

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    Saito, Takami; Soga, Kouichi; Hoson, Takayuki; Terashima, Ichiro

    2006-06-01

    We examined the relationship between the bulk elastic modulus (epsilon) of an individual leaf obtained by the pressure-volume (P-V) technique and the mechanical properties of cell walls in the leaf. The plants used were Quercus glauca and Q. serrata, an evergreen and a deciduous broad-leaved tree species, respectively. We compared epsilon and Young's modulus of leaf specimens determined by the stretch technique at various stages of their leaf development. The results showed that epsilon increased from approximately 5 to 20 MPa during leaf development, although other potential determinants of epsilon such as the apoplastic water content in the leaf and the diameter of a palisade tissue cells remained almost constant. epsilon in these two species was similar at every developmental stages, although the apparent mechanical strength of the leaf lamina and thickness of mesophyll cell walls were greater in Q. glauca. There were significant linear relationships between Young's modulus and epsilon (P < 0.01; R (2) = 0.78 and 0.84 in Q. glauca and Q. serrata, respectively) with small y-intercepts. From these results, we conclude that epsilon is closely related to the reversible properties of the cell walls. From the estimation of epsilon based on a physical model, we suggest that the effective thickness of cell walls responsible for epsilon is smaller than the observed wall thickness.

  13. Application of plant DNA markers in forensic botany: genetic comparison of Quercus evidence leaves to crime scene trees using microsatellites.

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    Craft, Kathleen J; Owens, Jeffrey D; Ashley, Mary V

    2007-01-05

    As highly polymorphic DNA markers become increasingly available for a wide range of plant and animal species, there will be increasing opportunities for applications to forensic investigations. To date, however, relatively few studies have reported using DNA profiles of non-human species to place suspects at or near crime scenes. Here we describe an investigation of a double homicide of a female and her near-term fetus. Leaf material taken from a suspect's vehicle was identified to be that of sand live oak, Quercus geminata, the same tree species that occurred near a shallow grave where the victims were found. Quercus-specific DNA microsatellites were used to genotype both dried and fresh material from trees located near the burial site and from the material taken from the suspect's car. Samples from the local population of Q. geminata were also collected and genotyped in order to demonstrate that genetic variation at four microsatellite loci was sufficient to assign leaves to an individual tree with high statistical certainty. The cumulative average probability of identity for these four loci was 2.06x10(-6). DNA was successfully obtained from the dried leaf material although PCR amplification was more difficult than amplification of DNA from fresh leaves. The DNA profiles of the dried leaves from the suspect's car did not match those of the trees near the crime scene. Although this investigation did not provide evidence that could be used against the suspect, it does demonstrate the potential for plant microsatellite markers providing physical evidence that links plant materials to live plants at or near crime scenes.

  14. Drought stress signals in modern and subfossil Quercus laurifolia (Fagaceae) leaves reflect winter precipitation in southern Florida tied to El Niño-Southern Oscillation activity

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    Wagner-Cremer, F.; Donders, T.H.; Visscher, H.

    2010-01-01

    In the present study, structural xeromorphic features in modern and subfossil Quercus laurifolia leaves from southern Florida were quantified to reconstruct past precipitation changes in sensitive terrestrial settings. Absolute cell numbers/mm2, quantified as epidermal cell density (ED) h

  15. The Occurrence of Charcoal Disease Caused by Biscogniauxia mediterranea on Chestnut-Leaved Oak (Quercus castaneifolia) in the Golestan Forests of Iran

    NARCIS (Netherlands)

    Mirabolfathy, M.; Groenewald, J.Z.; Crous, P.W.

    2011-01-01

    The chestnut-leaved oak (Quercus castaneifolia) is native to the Alborz Mountains, including the Golestan Forests, in northern Iran. Trees grow up to 35 (-50) m tall with a trunk up to 2.5 (-3.5) m in diameter. During 2010, we received reports of a decline of oak trees in the Ghorogh Region of the G

  16. Sewage sludge effects on mesofauna and cork oak (Quercus suber L.) leaves decomposition in a Mediterranean forest firebreak.

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    Pernin, Céline; Cortet, Jérôme; Joffre, Richard; Le Petit, Jean; Torre, Franck

    2006-01-01

    Effects of sewage sludge on litter mesofauna communities (Collembola and Acari) and cork oak (Quercus suber L.) leaf litter decomposition have been studied during 18 mo using litterbags in an in situ experimental forest firebreak in southeastern France. The sludge (2.74 t DM ha(-1) yr(-1)) was applied to fertilize and maintain a pasture created on the firebreak. Litterbag colonization had similar dynamics on both the control and fertilized plots and followed a typical Mediterranean pattern showing a greater abundance in spring and autumn and a lower abundance in summer. After 9 mo of litter colonization, Collembola and Acari, but mainly Oribatida, were more abundant on the sludge-fertilized plot. Leaf litter decomposition showed a similar pattern on both plots, but it was faster on the control plot. Furthermore, leaves from the fertilized plot were characterized by greater nitrogen content. Both chemical composition of leaves and sludges and the decomposition state of leaves have significantly affected the mesofauna community composition from each plot.

  17. RNA-seq analysis of Quercus pubescens Leaves: de novo transcriptome assembly, annotation and functional markers development.

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    Sara Torre

    Full Text Available Quercus pubescens Willd., a species distributed from Spain to southwest Asia, ranks high for drought tolerance among European oaks. Q. pubescens performs a role of outstanding significance in most Mediterranean forest ecosystems, but few mechanistic studies have been conducted to explore its response to environmental constrains, due to the lack of genomic resources. In our study, we performed a deep transcriptomic sequencing in Q. pubescens leaves, including de novo assembly, functional annotation and the identification of new molecular markers. Our results are a pre-requisite for undertaking molecular functional studies, and may give support in population and association genetic studies. 254,265,700 clean reads were generated by the Illumina HiSeq 2000 platform, with an average length of 98 bp. De novo assembly, using CLC Genomics, produced 96,006 contigs, having a mean length of 618 bp. Sequence similarity analyses against seven public databases (Uniprot, NR, RefSeq and KOGs at NCBI, Pfam, InterPro and KEGG resulted in 83,065 transcripts annotated with gene descriptions, conserved protein domains, or gene ontology terms. These annotations and local BLAST allowed identify genes specifically associated with mechanisms of drought avoidance. Finally, 14,202 microsatellite markers and 18,425 single nucleotide polymorphisms (SNPs were, in silico, discovered in assembled and annotated sequences. We completed a successful global analysis of the Q. pubescens leaf transcriptome using RNA-seq. The assembled and annotated sequences together with newly discovered molecular markers provide genomic information for functional genomic studies in Q. pubescens, with special emphasis to response mechanisms to severe constrain of the Mediterranean climate. Our tools enable comparative genomics studies on other Quercus species taking advantage of large intra-specific ecophysiological differences.

  18. Morphological variation of Quercus Iiaotungensis leaves in Lingkong Mountain,Shanxi Province

    Institute of Scientific and Technical Information of China (English)

    LI Mei; HAN Hairong; KANG Fengfeng; MA Qinyan

    2007-01-01

    In order to study variation of morphological traits and the influencing factors of natural populations of Quercus liaotungensis Koidz.in Lingkong Mountain Nature Reserve of Shanxi region,five populations were included,and 24 morphological traits of leaf and apical bud were investigated.The analysis of variance showed that variation of all the morphological traits within population were significant,whereas significant difference existed in five property indices among populations (α = 0.05),which resulted from genetic and environmental factors.The results revealed that direction and degree of slope,average diameter at breast height in populations,and population density were the main influencing factors.Intrapopulation variation mainly contributed to morphological variation,and the phenotypic differentiation coefficient was 13.31%,which indicated low level of differentiation.But several characteristics exhibited high differentiation level,such as width of the tooth of leaf base (25.99%) and the middle apical bud (25.23%).The morphological indices,including the tooth of leaf base,leaf tip,petiole,and leaf area were precarious and changed a lot within population,which arose from the variation of individual's development.However,only two morphological indices,the middle apical bud and the tooth of leaf base,are unstable,which indicates the extensive influence of environmental factors.

  19. Digestion and body weight change in Tuj lambs receiving oak (Quercus hartwissiana) leaves with and without PEG

    Energy Technology Data Exchange (ETDEWEB)

    Yildiz, S. [Department of Physiology, Faculty of Veterinary Sciences, Kafkas University, Kars (Turkey)]. E-mail: yildizsedat@hotmail.com; Kaya, I.; Unal, Y.; Aksu Elmali, D.; Kaya, S.; Oncuer, A. [Department of Animal Nutrition, Faculty of Veterinary Sciences, Kafkas University, Kars (Turkey); Cenesiz, M.; Kaya, M. [Department of Physiology, Faculty of Veterinary Sciences, Kafkas University, Kars (Turkey)

    2005-08-19

    Quercus hartwissiana (oak) leaves are a potential alternative feed resource in the north-east of Turkey. The aim of the current study was to evaluate the effects of two levels (185 and 370 g/day) of dry oak leaves, in the presence (50 or 100 g/kg of dry oak leaves) or absence of polyethylene glycol (PEG 6000), on ruminal fermentation parameters (pH, short-chain fatty acids (SCFA), ammonia nitrogen (NH{sub 3}-N)), microbial nitrogen (N) supply, apparent diet digestibility, N retention, and body weight (BW) change in fat-tailed Tuj lambs (n = 42, initial BW 33.0 {+-} 0.7 kg). The lambs received at random one of the following diets for 60 days (on a dry matter basis, n = 6 per group): (1) control, no oak leaves and no PEG; (2) 185 g oak leaves; (3) 185 g oak leaves + 10 g PEG; (4) 185 g oak leaves + 20 g PEG; (5) 370 g oak leaves; (6) 370 g oak leaves + 20 g PEG; (7) 370 g oak leaves + 40 g PEG. All groups were given 272 g concentrate and varying amounts of hay (a mixture of chopped grass and alfalfa in the ratio 55:45), such that the amount of hay plus oak leaves was equal to 645 g. Ruminal fermentation parameters did not change with treatment (pH 6.50 {+-} 0.02, total SCFA 86.3 {+-} 2.1 mmol/L, NH{sub 3}-N = 207 {+-} 5 mg/L). Total CP digestibility (0.775, 0.714, 0.736, 0.748, 0.663, 0.690, 0.672; S.E.M. = 0.008, P < 0.001, for groups 1-7, respectively) and N retention (7.7, 6.8, 6.7, 7.5, 6.1, 5.8, 5.7 g/day; S.E.M. = 0.19, P < 0.05, for groups 1-7, respectively) were lowest but microbial N supply was highest in 370 g oak leaf group supplemented with PEG (6.51, 7.14, 11.45, 12.23, 9.03, 14.49, 14.39 g/day, S.E.M. = 0.76, P < 0.05, for groups 1-7, respectively). Final BW (32.5 {+-} 0.3 kg) did not differ among treatments (P > 0.05). These data suggest that: (1) PEG addition seems unnecessary as it did not improve CP digestibility, N retention and BW; and (2) Q. hartwissiana leaves may be used to replace at least half of hay in the ration of Tuj lambs without a

  20. Antioxidant and α-glucosidase inhibitor activities of natural compounds isolated from Quercus gilva Blume leaves

    Directory of Open Access Journals (Sweden)

    Anastasia Wheni Indrianingsih

    2015-09-01

    Conclusions: The results obtained for the antioxidant activities and α-glucosidase inhibitory activities in a methanolic extract from the leaves of Q. gilva confirmed the potential of this plant as a source of natural antioxidants and antidiabetic medicine.

  1. Diurnal changes in photoprotective mechanisms in leaves of cork oak (Quercus suber) during summer

    Energy Technology Data Exchange (ETDEWEB)

    Faria, T.; Garcia-Plazaola, J. I.; Cerasoli, S.; Pereira, J. S.; Chaves, M. M. [Instituto Superior de Agronomia, Lisbon (Portugal). Dept. de Engenharia Florestal; Abadia, A.

    1996-01-01

    Diurnal variations in photoprotective mechanisms were studied in sun and shade leaves of 40-year old oak trees during early summer in Portugal. Stomatal conductance, and net carbon assimilation rate of sun leaves was found to be highest in the morning, declined substantially by midday and showed almost no recovery in the afternoon, despite the fact that the trees suffered no severe water deprivation as indicated by high predawn leaf water potential. The high positive linear correlation between photosynthesis and stomatal conductance suggests that stomatal closure is a feature of endogenous metabolic regulation rather than a short-term response to light, temperature or leaf-to-air water pressure deficit, and is the main factor limiting photosynthesis under the experimental conditions. 51 refs., 9 figs.

  2. A new approach to ozone plant fumigation: The Web-O3-Fumigation. Isoprene response to a gradient of ozone stress in leaves of Quercus pubescens

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    Tricoli D

    2008-02-01

    Full Text Available The innovative Web-O3-Fumigation (WOF is a suitable technique to study O3 effects in plants. Through WOF, a very high dose of O3 fumigation may be obtained at the level of selected leaves, while allowing a gradient of ozone stress in branches at different distance from branch directly fumigated with O3 diffusing from perforated Teflon tubes. We used WOF to study the impact of O3 on the emission of isoprene, a putatively powerful antioxidant, in leaves of Quercus pubescens. In our experiment we produced with WOF: i approximately 300 ppb O3 on the leaves of the branch directly exposed to the pollutant; ii approximately 190 ppb on the leaves of the branches distant less than 30 cm from the treated branch; iii a summer ambient O3 concentration (100 ppb on the leaves of the branches distant more than 30 cm from the branch directly fumigated. High O3 concentrations induced a long-lasting inhibition of photosynthesis and isoprene emission in leaves which were directly fumigated. However, isoprene emission was stimulated by intermediate O3 concentration 288 hours after the end of the treatment. Isoprene stimulation, and the activation of the related antioxidant mechanism, may therefore be dependent on the O3 concentration and may be different in plant canopies depending on their exposure to the pollutant

  3. A new approach to ozone plant fumigation: The Web-O3-Fumigation. Isoprene response to a gradient of ozone stress in leaves of Quercus pubescens.

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    Pinelli P

    2004-01-01

    Full Text Available The innovative Web-O3-Fumigation (WOF is a suitable technique to study O3 effects in plants. Through WOF, a very high dose of O3 fumigation may be obtained at the level of selected leaves, while allowing a gradient of ozone stress in branches at different distance from branch directly fumigated with O3 diffusing from perforated Teflon tubes. We used WOF to study the impact of O3 on the emission of isoprene, a putatively powerful antioxidant, in leaves of Quercus pubescens. In our experiment we produced with WOF: i approximately 300 ppb O3 on the leaves of the branch directly exposed to the pollutant; ii approximately 190 ppb on the leaves of the branches distant less than 30 cm from the treated branch; iii a summer ambient O3 concentration (100 ppb on the leaves of the branches distant more than 30 cm from the branch directly fumigated. High O3 concentrations induced a long-lasting inhibition of photosynthesis and isoprene emission in leaves which were directly fumigated. However, isoprene emission was stimulated by intermediate O3 concentration 288 hours after the end of the treatment. Isoprene stimulation, and the activation of the related antioxidant mechanism, may therefore be dependent on the O3 concentration and may be different in plant canopies depending on their exposure to the pollutant

  4. Sesquiterpenes from Cupressus macrocarpa foliage.

    Science.gov (United States)

    Cool, Laurence G

    2005-01-01

    Ten sesquiterpenes, many with unusual carbon skeletons, were identified in foliage of Cupressus macrocarpa. These are (-)-10-epi-beta-acoradiene; ent-widdra-2,4(14)-diene; (E)-iso-gamma-bisabolene, i.e., (4E)-4-(1,5-dimethylhex-5-enylidene)-1-methylcyclohexene; (-)-cumacrene, i.e., (4S)-4-[(1R,2S)-2-isopropenyl-1-methylcyclobutyl]-1-methylcyclohexene; (-)-alpha-chamipinene, i.e., (1S,6S,7S)-2,2,6,8-tetramethyltricyclo[5.3.1.01,6]undec-8-ene; and five sesquiterpenes with a 3,3,4'-trimethyl-1,1'-bi(cyclohexyl) skeleton for which the trivial name macrocarpane is proposed. The possible single-enzyme biogenesis of these sesquiterpenes is discussed.

  5. Photosynthetic responses to elevated CO{sub 2} and O{sub 3} in Quercus ilex leaves at a natural CO{sub 2} spring

    Energy Technology Data Exchange (ETDEWEB)

    Paoletti, E. [Istituto Protezione Piante, Consiglio Nazionale delle Ricerche, Via Madonna del Piano 10, I-50019 Sesto Fiorentino, Florence (Italy)]. E-mail: e.paoletti@ipp.cnr.it; Seufert, G. [European Commission, Joint Research Centre, Institute for Environment and Sustainability, I-21020 Ispra (Italy); Della Rocca, G. [Istituto Protezione Piante, Consiglio Nazionale delle Ricerche, Via Madonna del Piano 10, I-50019 Sesto Fiorentino, Florence (Italy); Thomsen, H. [European Commission, Joint Research Centre, Institute for Environment and Sustainability, I-21020 Ispra (Italy)

    2007-06-15

    Photosynthetic stimulation and stomatal conductance (Gs) depression in Quercus ilex leaves at a CO{sub 2} spring suggested no down-regulation. The insensitivity of Gs to a CO{sub 2} increase (from ambient 1500 to 2000 {mu}mol mol{sup -1}) suggested stomatal acclimation. Both responses are likely adaptations to the special environment of CO{sub 2} springs. At the CO{sub 2}-enriched site, not at the control site, photosynthesis decreased 9% in leaves exposed to 2x ambient O{sub 3} concentrations in branch enclosures, compared to controls in charcoal-filtered air. The stomatal density reduction at high CO{sub 2} was one-third lower than the concomitant Gs reduction, so that the O{sub 3} uptake per single stoma was lower than at ambient CO{sub 2}. No significant variation in monoterpene emission was measured. Higher trichome and mesophyll density were recorded at the CO{sub 2}-enriched site, accounting for lower O{sub 3} sensitivity. A long-term exposure to H{sub 2}S, reflected by higher foliar S-content, and CO{sub 2} might depress the antioxidant capacity of leaves close to the vent and increase their O{sub 3} sensitivity. - Very high CO{sub 2} concentrations did not compensate for the effects of O{sub 3} on holm oak photosynthesis.

  6. Effect of feeding tannin degrading bacterial culture (Streptococcus gallolyticus strain TDGB 406) on nutrient utilization, urinary purine derivatives and growth performance of goats fed on Quercus semicarpifolia leaves.

    Science.gov (United States)

    Kumar, K; Chaudhary, L C; Agarwal, N; Kamra, D N

    2014-10-01

    To study the effect of supplementation of tannin degrading bacterial culture (Streptococcus gallolyticus strain TDGB 406) on growth performance, nutrient utilization and urinary purine derivatives of goats fed on oak (Quercus semicarpifolia) leaves. For growth study, eighteen billy goats (4 month old, average body weight 9.50 ± 1.50 kg) were distributed into three groups of six animals each. The animals of group 1 served as control while animals of groups 2 (T1) and 3 (T2) were given (@ 5 ml/kg live weight) autoclaved and live culture of isolate TDGB 406 (10(6) cells/ml) respectively. The animals were fed measured quantity of dry oak leaves as the main roughage source and ad libitum maize hay along with fixed quantity of concentrate mixture. The feeding of live culture of isolate TDGB 406 (probiotic) did not affect dry matter intake and digestibility of nutrients except that of dry matter and crude protein, which was higher in T2 group as compared to control. All the animals were in positive nitrogen balance. There was no significant effect of feeding isolate TDGB 406 on urinary purine derivatives (microbial protein production) in goats. The body weight gain and average live weight gain was significantly higher (p = 0.071) in T2 group as compared to control. Feed conversion efficiency was also better in the goats fed on live culture of TDGB 406 (T2). The feeding of tannin degrading bacterial isolate TDGB 406 as probiotic resulted in improved growth performance and feed conversion ratio in goats fed on oak leaves as one of the main roughage source. Journal of Animal Physiology and Animal Nutrition © 2013 Blackwell Verlag GmbH.

  7. Effects of seasonal change and experimental warming on the temperature dependence of photosynthesis in the canopy leaves of Quercus serrata.

    Science.gov (United States)

    Yamaguchi, Daisuke P; Nakaji, Tatsuro; Hiura, Tsutom; Hikosaka, Kouki

    2016-10-01

    The effects of warming on the temperature response of leaf photosynthesis have become an area of major concern in recent decades. Although growth temperature (GT) and day length (DL) affect leaf gas exchange characteristics, the way in which these factors influence the temperature dependence of photosynthesis remains uncertain. We established open-top canopy chambers at the canopy top of a deciduous forest, in which average daytime leaf temperature was increased by 1.0 °C. We conducted gas exchange measurements for the canopy leaves of deciduous trees exposed to artificial warming during different seasons. The carbon dioxide assimilation rate at 20 °C (A20) was not affected by warming, whereas that at 25 °C (A25) tended to be higher in leaves exposed to warming. Warming increased the optimal temperature of photosynthesis by increasing the activation energy for the maximum rate of carboxylation. Regression analysis indicated that both GT and DL strongly influenced gas exchange characteristics. Sensitivity analysis revealed that DL affected A without obvious effects on the temperature dependence of A, whereas GT almost maintained constant A20 and strongly influenced the temperature dependence. These results indicate that GT and DL have different influences on photosynthesis; GT and DL affect the 'slope' and intercept' of the temperature dependence of photosynthesis, respectively. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  8. Phytochemistry and medicinal properties of Phaleria macrocarpa (Scheff. Boerl. extracts

    Directory of Open Access Journals (Sweden)

    Rabia Altaf

    2013-01-01

    Full Text Available Phaleria macrocarpa, commonly known as Mahkota dewa is a medicinal plant that is indigenous to Indonesia and Malaysia. Extracts of P. macrocarpa have been used since years in traditional medicine that are evaluated scientifically as well. The extracts are reported for a number of valuable medicinal properties such as anti-cancer, anti-diabetic, anti-hyperlipidemic, anti-inflammatory, anti-bacterial, anti-fungal, anti-oxidant and vasorelaxant effect. The constituents isolated from different parts of P. macrocarpa include Phalerin, gallic acid, Icaricide C, magniferin, mahkoside A, dodecanoic acid, palmitic acid, des-acetylflavicordin-A, flavicordin-A, flavicordin-D, flavicordin-A glucoside, ethyl stearate, lignans, alkaloids andsaponins. The present review is an up-to-date summary of occurrence, botanical description, ethnopharmacology, bioactivity and toxicological studies related to P. macrocarpa.

  9. Dimeric and trimeric hydrolyzable tannins from Quercus coccifera and Quercus suber.

    Science.gov (United States)

    Ito, Hideyuki; Yamaguchi, Koji; Kim, Tae-Hoon; Khennouf, Seddik; Gharzouli, Kamel; Yoshida, Takashi

    2002-03-01

    Three new hydrolyzable tannins, cocciferins D(1) (1), D(2) (2), and T(1) (4), were isolated from the leaves of Quercus coccifera. Cocciferin D(2) (2) and two additional new tannins, cocciferins D(3) (3) and T(2) (5), were also obtained from the leaves of Quercus suber. Their oligomeric structures were elucidated on the basis of spectroscopic methods and chemical evidence. Compounds 2, 3, and 5 were rare oligomers possessing glucose cores with both open-chain and pyranose forms.

  10. Chemical constituents of Sebastiania macrocarpa Muell. Arg. (Euphorbiaceae); Constituintes quimicos de Sebastiania macrocarpa Muell. Arg. (Euphorbiaceae)

    Energy Technology Data Exchange (ETDEWEB)

    Lima, Michele A.A.; Lima, Jefferson Q.; Arriaga, Angela M.C.; Andrade-Neto, Manoel; Braz-Filho, Raimundo [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil). Dept. de Quimica Organica e Inorganica; Santiago, Gilvandete M.P.; Bezerra, Beatriz P.; Fereira, Yana S.; Veras, Helenicy N.H. [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil). Faculdade de Farmacia, Odontologia e Enfermagem. Dept. de Farmacia]. E-mail: gil@ufc.br

    2009-07-01

    The chemical investigation of the methanolic extract of the aerial part of Sebastiania macrocarpa allowed the isolation of the mixture of steroids {beta}-sitosterol and stigmasterol, gallic acid, and scopoletin. The hexane extract of the roots allowed the isolation of the triterpene lupeol and of the macrocyclic diterpene (+)-tonantzitlolone. The structures of all compounds isolated were identified on the basis of their spectral data and by comparison of their spectral data with values described in the literature. This is the first report involving the chemical investigation of this species (author)

  11. Top-down control of herbivory by birds and bats in the canopy of temperate broad-leaved oaks (Quercus robur.

    Directory of Open Access Journals (Sweden)

    Stefan M Böhm

    Full Text Available The intensive foraging of insectivorous birds and bats is well known to reduce the density of arboreal herbivorous arthropods but quantification of collateral leaf damage remains limited for temperate forest canopies. We conducted exclusion experiments with nets in the crowns of young and mature oaks, Quercus robur, in south and central Germany to investigate the extent to which aerial vertebrates reduce herbivory through predation. We repeatedly estimated leaf damage throughout the vegetation period. Exclusion of birds and bats led to a distinct increase in arthropod herbivory, emphasizing the prominent role of vertebrate predators in controlling arthropods. Leaf damage (e.g., number of holes differed strongly between sites and was 59% higher in south Germany, where species richness of vertebrate predators and relative oak density were lower compared with our other study site in central Germany. The effects of bird and bat exclusion on herbivory were 19% greater on young than on mature trees in south Germany. Our results support previous studies that have demonstrated clear effects of insectivorous vertebrates on leaf damage through the control of herbivorous arthropods. Moreover, our comparative approach on quantification of leaf damage highlights the importance of local attributes such as tree age, forest composition and species richness of vertebrate predators for control of arthropod herbivory.

  12. Vegetative propagation of Quercus suber L. by somatic embryogenesis. I. Factors affecting the induction in leaves from mature cork oak trees.

    Science.gov (United States)

    Hernández, I; Celestino, C; Toribio, M

    2003-04-01

    Somatic embryogenesis was induced in expanding leaves from epicormic shoots forced to sprout from segments of branches collected from several hundred-year-old cork oak trees. Following a basic protocol previously defined for leaves taken from seedlings of this species, several factors were studied to improve the response. The induction frequency was significantly higher when the length of exposure to growth regulators was increased from 7 to 30 days. The combined application of NAA and BAP was essential for induction. Although both regulators had a very significant influence, their interaction was not significant, suggesting independent roles. Leaf size had a crucial effect, because beyond a certain threshold, embryogenesis could not be obtained. Embryogenic lines were maintained via repetitive embryogenesis on hormone-free medium for more than 2 years.

  13. 蒙古栎不同冠层部位叶片养分动态%Nutrient dynamics in Quercus mongolica leaves at different canopy positions

    Institute of Scientific and Technical Information of China (English)

    程徐冰; 韩士杰; 张忠辉; 周玉梅; 王树起; 王学娟

    2011-01-01

    以长白山原始针阔叶混交林优势树种蒙古栎为对象,研究了6-10月生长季不同冠层叶片单位叶面积质量(LMA)、单位质量和单位叶面积的C、N、P含量变化,以及N、P的再吸收效率与利用效率.结果表明:在生长季,蒙古栎冠层上、下部叶片的LMA和单位叶面积C含量(Carea)表现出明显的月动态变化;单位叶面积N、P含量(Narea、Parea)的月变化趋势与单位质量N、P含量(Nmass、Pmass)相似,而用单位叶面积与单位质量表示的N、P再吸收效率无明显差异.冠层位置对N的再吸收效率和利用效率无明显影响,但冠层上部P的再吸收效率和利用效率显著高于冠层下部.在未来气候变化情景下,蒙古栎较高的生存力和竞争力有助于促进生态系统的养分循环.%Taking the dominant tree species Quercus mongolica in natural coniferous-broadleaved mixed forest in Changbai Mountains as test object, this paper studied the variations of leaf dry mass per unit area ( LMA), leaf carbon (C), nitrogen ( N), and phosphorus ( P) contents per unit mass and per unit area, as well as the leaf N and P resorption efficiency and use efficiency at upper and lower canopy positions during growth season (from June to October). In the growth season, and at both upper and lower canopy positions, the LMA and leaf C content per unit area had obvi-ous monthly fluctuation, the leaf N and P contents per unit area had the similar monthly variation trend with the leaf N and P contents per unit mass, but the leaf N and P resorption efficiency per unit mass had no significant difference with the leaf N and P resorption efficiency per unit area. The leaf N resorption efficiency and use efficiency were less affected by canopy position, but the leaf P resorption efficiency and use efficiency were higher at upper canopy than at lower canopy. Under the scenario of future climate change, the higher survival and competitive capabilities of Q. mongol-ica would

  14. Operculina macrocarpa: chemical and intestinal motility effect in mice

    Directory of Open Access Journals (Sweden)

    Daniele Michelin Paganotte

    Full Text Available ABSTRACT Operculina macrocarpa (L. Urb., Convolvulaceae, is used by the population as a laxative. In this work we described the isolation of the three phenolic acids present in the hydroethanolic extract of the O. macrocarpa roots. The quantification of the caffeic, chlorogenic acids and of the new caffeic dimer in the hydroethanolic and infusion extracts was performed by high-performance liquid chromatography coupled photodiode array detector. These analyses showed the higher content of the chlorogenic, caffeic and the new 3,4'-dehydrodicaffeic acid in hydroethanolic and hydroethanolic extracts without resin in which infusion. The acid found in greater quantity is caffeic acid followed by the 3,4'-dehydrodicaffeic acid. The laxative activity was evaluated by different experimental models of intestinal transit with the hydroethanolic and infusion extracts, and the resin fraction, caffeic, chlorogenic and ferulic acids. The results showed all extracts and compounds tested had significant activity in the experimental model tested. These results obtained are essential for the future development of a pharmaceutical product with safety and efficacy.

  15. Volatile Organic Compound Emission from Quercus suber, Quercus canariensis, and its hybridisation product Quercus afares

    Science.gov (United States)

    Welter, S.; Bracho Nuñez, A.; Staudt, M.; Kesselmeier, J.

    2009-04-01

    Oaks represent one of the most important plant genera in the Northern hemisphere and include many intensively VOC emitting species. The major group constitutes the isoprene emitters, but also monoterpene emitters and non-emitters can be found. These variations in the oak species might partly be due to their propensity for inter- and intraspecific hybridisation. This study addresses the foliar VOC production of the former hybridisation product the deciduous Quercus afares and its parents, two very distant species: the evergreen monoterpene emitter Quercus suber and the deciduous isoprene emitter Quercus canariensis. The measurements were performed in Southern France, applying two different methods. Plants were investigated in situ in the field with a portable gas exchange measuring system as well as in the laboratory on cut branches with an adapted enclosure system. Quercus afares was found to be a monoterpene emitting species. However, the monoterpene emission was lower and the composition different to that of Quercus suber. Whereas Quercus suber trees belonged to the pinene type most individuals of Quercus afares were identified to represent a limonene type. Quercus canariensis emitted besides high amounts of isoprene also linalool and (Z)-3-hexenylacetate. Emissions from Quercus suber and Quercus afares were higher in the field measurements than in the laboratory on cut branches whereas Quercus canariensis exhibited lower isoprene emissions from cut branches. The results demonstrate the need of further emission studies on a plant species level.

  16. A new cycloartane nortriterpenoid from Quercus variabilis Blume

    Institute of Scientific and Technical Information of China (English)

    Yan Xin; Ling Yun Jia; Jiu Zhi Yuan; Qi Shi Sun

    2009-01-01

    The leaves and stems of Quercus variabilis Blume afforded a new cycloartane nortriterpenoid, 3α-acetyloxy-4α, 14α-dimethyl9β, 19-cycloergost-24-oic acid (1), along with five known compounds (2-6). The structure of I was elucidated by 1D and 2D NMR and mass spectroscopy.

  17. The seasonal variation of the chemical composition of essential oils from Porcelia macrocarpa R.E. Fries (Annonaceae) and their antimicrobial activity.

    Science.gov (United States)

    da Silva, Erica Biolcati P; Soares, Marisi G; Mariane, Bruna; Vallim, Marcelo A; Pascon, Renata C; Sartorelli, Patricia; Lago, João Henrique G

    2013-11-01

    This study investigates the impact of seasonal variation on the chemical composition of essential oils from the leaves of Porcelia macrocarpa (Annonaceae) obtained over the course of one year (January-December 2011) and the chemical composition of the essential oils obtained from the ripe fruits of the same plant. Furthermore, the essential oils of the leaves were investigated with respect to their antimicrobial activity. The essential oils of the leaves contain a mixture of monoterpenes, one diterpene and several sesquiterpenes. The main components were identified as the sesquiterpenes germacrene D (29%-50%) and bicyclogermacrene (24%-37%). No significant variation was observed for the composition of the essential oil of the leaves over the course of the year, except for the month of November, when the ripe fruit were collected. In this month, substantially decreased concentrations of germacrene D (28.8 ± 0.8%) and bicyclogermacrene (23.9 ± 0.6%) were measured and the emergence of spathulenol (10.4 ± 0.2%) was observed. The essential oils extracted from the ripe fruit revealed the presence of a variety of monoterpenes, sesquiterpenes and hydrocarbons. The main constituents of these oils were neryl (8.8 ± 0.2%) and geranyl (27.3 ± 0.7%) formates, γ-muurolene (10.3 ± 0.9%) and dendrolasin (8.23 ± 0.06%). The antimicrobial activity of the essential oil obtained from the leaves of P. macrocarpa towards a range of bacterial and yeast strains was examined. In order to determine the minimum inhibitory concentration (MIC) of essential oils obtained from the January collection of the leaves, broth microdilution assays were carried out, which showed a significant antimicrobial activity towards Cryptococcus neoformans serotypes A and D as well as C. gattii serotypes B and C.

  18. Production of secondary metabolite E2.2 from Phaleria macrocarpa endophytic fungus

    Institute of Scientific and Technical Information of China (English)

    Beatrix Trikurnia Gasong; Raymond Rubianto Tjandrawinata

    2016-01-01

    Objective: To isolate new endophytic fungus from Phaleria macrocarpa (P. macrocarpa) that is able to produce E2.2 compound. Methods: Endophytic fungi were isolated from P. macrocarpa. Morphological and molecular identification was done to determine the species of the endophytic fungus. High performance liquid chromatography was used to determine the ability of this fungus to produce E2.2 compound and to quantify the total yield of E2.2 from fungal fermen-tation. Fermentation process was optimized by observing suitable medium, pH and length of fermentation process. Phloroglucinol and gallic acid addition were examined to determine the effect of each compound on E2.2 production. Results: One endophytic fungus was successfully isolated from P. macrocarpa plant. Morphological and molecular identification showed that it was a Colletotrichum gloeo-sporioides which belonged to Glomerellaceae family. This fungus showed highest pro-duction of E2.2 when incubated in potato dextrose broth with initial pH value of the medium at 5, and was incubated for 15 days. Phloroglucinol was found to better enhance E2.2 production. Conclusions: Colletotrichum gloeosporioides found in P. macrocarpa plant is prom-ising as a potential alternative source of E2.2.

  19. y Quercus laurina

    Directory of Open Access Journals (Sweden)

    R. Flores-Velázquez

    2007-01-01

    Full Text Available Se determinaron las características de maquinado con base en la norma ASTM D 1666-87, en las operaciones de cepillado, barrenado, moldurado, torneado y lijado de la madera de Quercus affinis y Quercus laurina. Los mejores resultados de cepillado para Q. affinis se encontraron al combinar el ángulo de corte de 15º y una velocidad de alimentación de 7.5 m·min-1, para Q. laurina no hubo influencia del ángulo de corte. En el barrenado se obtuvieron excelentes resultados con las dos velocidades de giro de broca probadas. Para el moldurado, los resultados para las dos especies fueron excelentes en ambos cortes. En el torneado se encontró que no existe influencia del contenido de humedad para Q. laurina, mientras que para Q. affinis se clasificó como buena para un contenido de humedad menor y excelente para el mayor contenido de humedad. Y para el lijado los resultados fueron excelentes. De acuerdo a los resultados de las pruebas, las dos especies son apropiadas para ser utilizadas por la industria maderera para la elaboración de productos terminados de alta calidad.

  20. Antimicrobial and Anti-Inflammatory Activities of Pterygota macrocarpa and Cola gigantea (Sterculiaceae

    Directory of Open Access Journals (Sweden)

    Christian Agyare

    2012-01-01

    Full Text Available Pterygota macrocarpa and Cola gigantea are African medicinal plants used in traditional medicine for the treatment of sores, skin infections, and other inflammatory conditions including pains. This study therefore aims at investigating the antimicrobial properties of ethanol leaf and stem bark extracts of P. macrocarpa and C. gigantea using the agar diffusion and the micro-dilution techniques and also determining the anti-inflammatory properties of the extracts of these plants in carrageenan-induced foot edema in seven-day old chicks. The minimum inhibitory concentration of both ethanol leaf and bark extracts of P. macrocarpa against the test organisms was from 0.125 to 2.55 mg/mL and that of C. gigantea extracts was 0.125 to 2.75 mg/mL. Extracts with concentration of 50 mg/mL were most active against the test organisms according to the agar diffusion method. All the extracts of P. macrocarpa and C. gigantea at 30, 100, and 300 mg/kg body weight except ethanol leaf extract of C. gigantea exhibited significant anti-inflammatory effects (≤0.001.

  1. Flavonoid Analyses and Antimicrobial Activity of Various Parts of Phaleria macrocarpa (Scheff. Boerl Fruit

    Directory of Open Access Journals (Sweden)

    Ehsan Oskoueian

    2011-05-01

    Full Text Available Phaleria macrocarpa (Scheff. Boerl (Thymelaceae is commonly known as ‘Crown of God’, ‘Mahkota Dewa’, and ‘Pau’. It originates from Papua Island, Indonesia and it grows in tropical areas. Empirically, it is potent in treating the hypertensive,diabetic, cancer and diuretic patients. It has a long history of ethnopharmacological usage, and the lack of information about its biological activities led us to investigate the possible biological activities by characterisation of flavonoids and antimicrobial activity of various part of P. macrocarpa against pathogenic bacteria and fungi. The results showed that kaempferol, myricetin, naringin, and rutin were the major flavonoids present in the pericarp while naringin and quercetin were found in the mesocarp and seed. Furthermore, the antibacterial activity of different parts of P. macrocarpa fruit showed a weak ability to moderate antibacterial activity against pathogenic tested bacteria (inhibition range: 0.93–2.17 cm at concentration of 0.3 mg/disc. The anti fungi activity was only found in seed extract against Aspergillus niger (1.87 cm at concentration of 0.3 mg/well. From the results obtained, P. macrocarpa fruit could be considered as a natural antimicrobial source due to the presence of flavonoid compounds.

  2. Morphological Response of Eight Quercus Species to Simulated Wind Load.

    Science.gov (United States)

    Wu, Tonggui; Zhang, Peng; Zhang, Lei; Wang, Geoff G; Yu, Mukui

    Leaf shape, including leaf size, leaf dissection index (LDI), and venation distribution, strongly impacts leaf physiology and the forces of momentum exerted on leaves or the canopy under windy conditions. Yet, little has been known about how leaf shape affects the morphological response of trees to wind load. We studied eight Quercus species, with different leaf shapes, to determine the morphological response to simulated wind load. Quercus trees with long elliptical leaves, were significantly affected by wind load (Pwind load, such as bigger leaf thickness, larger stem diameter, allocation to root biomass, and smaller stem height (Pwind can reduce drag and increase the mechanical strength of the tree. Leaf dissection index (LDI), an important index of leaf shape, was correlated with morphological response to wind load (Pwind load.

  3. Morphological Response of Eight Quercus Species to Simulated Wind Load

    Science.gov (United States)

    Zhang, Peng; Zhang, Lei; Wang, Geoff G.; Yu, Mukui

    2016-01-01

    Leaf shape, including leaf size, leaf dissection index (LDI), and venation distribution, strongly impacts leaf physiology and the forces of momentum exerted on leaves or the canopy under windy conditions. Yet, little has been known about how leaf shape affects the morphological response of trees to wind load. We studied eight Quercus species, with different leaf shapes, to determine the morphological response to simulated wind load. Quercus trees with long elliptical leaves, were significantly affected by wind load (PSLA), stem base diameter and stem height under windy conditions when compared to the control. The Quercus trees with leaves characterized by lanceolate or sinuous edges, showed positive morphological responses to wind load, such as bigger leaf thickness, larger stem diameter, allocation to root biomass, and smaller stem height (PSLA, in stem base diameter and in allocation to root biomass. These results suggest that trees with higher LDI, such as those with more and/or deeper lobes, are better adapted to wind load. PMID:27662594

  4. Phytochemical screening, cytotoxicity and antiviral activity of hexane fraction of Phaleria macrocarpa fruits

    Science.gov (United States)

    Ismaeel, Mahmud Yusef Yusef; Yaacob, Wan Ahmad; Tahir, Mariya Mohd.; Ibrahim, Nazlina

    2015-09-01

    Phaleria macrocarpa fruits have been widely used in the traditional medicine for the treatment of several infections. The current study was done to determine the phytochemical content, cytotoxicity and antiviral activity of the hexane fraction (HF) of P. macrocarpa fruits. In the hexane fraction of P. macarocarpa fruits, phytochemical screening showed the presence of terpenoids whereas saponins, alkaloids, tannins and anthraquinones were not present. Evaluation on Vero cell lines by using MTT assay showed that the 50% cytotoxic concentration (CC50) value was 0.48 mg/mL indicating that the fraction is not cytotoxic. Antiviral properties of the plant extracts were determined by plaque reduction assay. The effective concentration (EC50) was 0.18 mg/mL. Whereas the selective index (SI = CC50/EC50) of hexane fraction is 2.6 indicating low to moderate potential as antiviral agent.

  5. Cytotoxicity and antiviral activities of Asplenium nidus, Phaleria macrocarpa and Eleusine indica

    Science.gov (United States)

    Tahir, Mariya Mohd; Ibrahim, Nazlina; Yaacob, Wan Ahmad

    2014-09-01

    Three local medicinal plants namely Asplenium nidus (langsuyar), Eleusine indica (sambau) and Phaleria macrocarpa (mahkota dewa) were screened for the cytotoxicity and antiviral activities. Six plant extracts were prepared including the aqueous and methanol extracts from A. nidus leaf and root, aqueous extract from dried whole plant of E. indica and methanol extract from P. macrocarpa fruits. Cytotoxicity screening in Vero cell line by MTT assay showed that the CC50 values ranged from 15 to 60 mg/mL thus indicating the safety of the extracts even at high concentrations. Antiviral properties of the plant extracts were determined by plaque reduction assay. The EC50 concentrations were between 3.2 to 47 mg/mL. The selectivity indices (SI = CC50/EC50) of each tested extracts ranged from 4.3 to 63.25 indicating the usefulness of the extracts as potential antiviral agents.

  6. Wound-healing potential of the fruit extract of Phaleria macrocarpa

    Directory of Open Access Journals (Sweden)

    Walaa Najm Abood

    2015-05-01

    Full Text Available The wound-healing potential of Phaleria macrocarpa was evaluated by monitoring the levels of inflammatory mediators, collagen, and antioxidant enzymes. Experimentally, two-centimeter-wide full-thickness-deep skin excision wounds were created on the posterior neck area of the rats. The wounds were topically treated with gum acacia as a vehicle in the control group, intrasite gel in the reference group, and 100 and 200 mg/mL P. macrocarpa ‎fruit extract in the treatment group. Granulation tissues were excised on the 15th day and were further processed for histological and biochemical analyzes. Wound healing was evaluated by measuring the contractions and protein contents of the wounds. Cellular redistribution and collagen deposition were assessed morphologically using Masson’s trichrome stain. Superoxide dismutase (SOD and catalase (CAT activities, along with malondialdehyde (MDA level were determined in skin tissue homogenates of the dermal wounds. Serum levels of transforming growth factor beta 1 (TGF-β1 and tumor necrosis factor alpha (TNF-α were evaluated in all the animals. A significant decrease in wound area was caused by a significant increase in TGF-β1 level in the treated groups. Decrease in TNF-α level and increase in the collagen formation were also observed in the treated groups. Topical treatment with P. macrocarpa fruit extract increased the SOD and CAT activities in the healing wounds, thereby significantly increasing MDA level. The topical treatment with P. macrocarpa fruit extract showed significant healing effect on excision wounds and demonstrated an important role in the inflammation process by increasing antioxidant enzyme activities, thereby accelerating the wound healing process and reducing tissue injury.

  7. Wound-healing potential of the fruit extract of Phaleria macrocarpa.

    Science.gov (United States)

    Abood, Walaa Najm; Al-Henhena, Nawal Ahmed; Najim Abood, Ammar; Al-Obaidi, Mazen M Jamil; Ismail, Salmah; Abdulla, Mahmood Ameen; Al Bartan, Rami

    2015-01-01

    The wound-healing potential of Phaleria macrocarpa was evaluated by monitoring the levels of inflammatory mediators, collagen, and antioxidant enzymes. Experimentally, two-centimeter-wide full-thickness-deep skin excision wounds were created on the posterior neck area of the rats. The wounds were topically treated with gum acacia as a vehicle in the control group, intrasite gel in the reference group, and 100 and 200 mg/mL P. macrocarpa ‎fruit extract in the treatment group. Granulation tissues were excised on the 15th day and were further processed for histological and biochemical analyzes. Wound healing was evaluated by measuring the contractions and protein contents of the wounds. Cellular redistribution and collagen deposition were assessed morphologically using Masson's trichrome stain. Superoxide dismutase (SOD) and catalase (CAT) activities, along with malondialdehyde (MDA) level were determined in skin tissue homogenates of the dermal wounds. Serum levels of transforming growth factor beta 1 (TGF-β1) and tumor necrosis factor alpha (TNF-α) were evaluated in all the animals. A significant decrease in wound area was caused by a significant increase in TGF-β1 level in the treated groups. Decrease in TNF-α level and increase in the collagen formation were also observed in the treated groups. Topical treatment with P. macrocarpa fruit extract increased the SOD and CAT activities in the healing wounds, thereby significantly increasing MDA level. The topical treatment with P. macrocarpa fruit extract showed significant healing effect on excision wounds and demonstrated an important role in the inflammation process by increasing antioxidant enzyme activities, thereby accelerating the wound healing process and reducing tissue injury.

  8. Antioxidants, Phytochemicals, and Cytotoxicity Studies on Phaleria macrocarpa (Scheff. Boerl Seeds

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    Ma Ma Lay

    2014-01-01

    Full Text Available In recent years, the utilization of certain medicinal plants as therapeutic agents has drastically increased. Phaleria macrocarpa (Scheff. Boerl is frequently used in traditional medicine. The present investigation was undertaken with the purpose of developing pharmacopoeial standards for this species. Nutritional values such as ash, fiber, protein, fat, and carbohydrate contents were investigated, and phytochemical screenings with different reagents showed the presence of flavonoids, glycosides, saponin glycosides, phenolic compounds, steroids, tannins, and terpenoids. Our results also revealed that the water fraction had the highest antioxidant activity compared to the methanol extract and other fractions. The methanol and the fractionated extracts (hexane, chloroform, ethyl acetate, and water of P. macrocarpa seeds were also investigated for their cytotoxic effects on selected human cancer cells lines (MCF-7, HT-29, MDA-MB231, Ca Ski, and SKOV-3 and a normal human fibroblast lung cell line (MRC-5. Information from this study can be applied for future pharmacological and therapeutic evaluations of the species, and may assist in the standardization for quality, purity, and sample identification. To the best of our knowledge, this is the first report on the phytochemical screening and cytotoxic effect of the crude and fractionated extracts of P. macrocarpa seeds on selected cells lines.

  9. Antioxidants, phytochemicals, and cytotoxicity studies on Phaleria macrocarpa (Scheff.) Boerl seeds.

    Science.gov (United States)

    Lay, Ma Ma; Karsani, Saiful Anuar; Banisalam, Behrooz; Mohajer, Sadegh; Abd Malek, Sri Nurestri

    2014-01-01

    In recent years, the utilization of certain medicinal plants as therapeutic agents has drastically increased. Phaleria macrocarpa (Scheff.) Boerl is frequently used in traditional medicine. The present investigation was undertaken with the purpose of developing pharmacopoeial standards for this species. Nutritional values such as ash, fiber, protein, fat, and carbohydrate contents were investigated, and phytochemical screenings with different reagents showed the presence of flavonoids, glycosides, saponin glycosides, phenolic compounds, steroids, tannins, and terpenoids. Our results also revealed that the water fraction had the highest antioxidant activity compared to the methanol extract and other fractions. The methanol and the fractionated extracts (hexane, chloroform, ethyl acetate, and water) of P. macrocarpa seeds were also investigated for their cytotoxic effects on selected human cancer cells lines (MCF-7, HT-29, MDA-MB231, Ca Ski, and SKOV-3) and a normal human fibroblast lung cell line (MRC-5). Information from this study can be applied for future pharmacological and therapeutic evaluations of the species, and may assist in the standardization for quality, purity, and sample identification. To the best of our knowledge, this is the first report on the phytochemical screening and cytotoxic effect of the crude and fractionated extracts of P. macrocarpa seeds on selected cells lines.

  10. Antioxidant, Anti-inflammatory and Cytotoxicity of Phaleria macrocarpa (Boerl. Scheff Fruit

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    Hendra Rudi

    2011-11-01

    Full Text Available Abstract Background Phaleria macrocarpa (Scheff. Boerl (Thymelaceae originates from Papua Island, Indonesia and grows in tropical areas. The different parts of the fruit of P. macrocarpa were evaluated for antioxidant, anti-inflammatory, and cytotoxic activities. Methods Phaleria macrocarpa fruit were divided into pericarp, mesocarp and seed. All parts of the fruit were reflux extracted with methanol. The antioxidant activity of the extracts were characterized in various in vitro model systems such as FTC, TBA, DPPH radical, reducing power and NO radical. Anti-inflammatory assays were done by using NO production by macrophage RAW 264.7 cell lines induced by LPS/IFN-γ and cytotoxic activities were determined by using several cancer cell lines and one normal cell line Results The results showed that different parts (pericarp, mesocarp, and seed of Phaleria macrocarpa fruit contain various amount of total phenolic (59.2 ± 0.04, 60.5 ± 0.17, 47.7 ± 1.04 mg gallic acid equivalent/g DW and flavonoid compounds (161.3 ± 1.58, 131.7 ± 1.66, 35.9 ± 2.47 mg rutin equivalent/g DW. Pericarp and mesocarp showed high antioxidant activities by using DPPH (71.97%, 62.41%, ferric reducing antioxidant power (92.35%, 78.78% and NO scavenging activity (65.68%, 53.45%. Ferric thiocyanate and thiobarbituric acid tests showed appreciable antioxidant activity in the percentage hydroperoxides inhibitory activity from pericarp and mesocarp in the last day of the assay. Similarly, the pericarp and mesocarp inhibited inducible nitric oxide synthesis with values of 63.4 ± 1.4% and 69.5 ± 1.4% in macrophage RAW 264.7 cell lines induced by LPS/IFN-γ indicating their notable anti-inflammatory potential. Cytotoxic activities against HT-29, MCF-7, HeLa and Chang cell lines were observed in all parts. Conclusions These results indicated the possible application of P. macrocarpa fruit as a source of bioactive compounds, potent as an antioxidant, anti inflammatory and

  11. Efek Teratogenik Ekstrak Buah Mahkota Dewa (Phaleria macrocarpa (Scheff. Boerl. pada Tikus Putih (Rattus norvegicus L. Galur Winstar

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    SHANTI LISTYAWATI

    2006-11-01

    Full Text Available Earlier experiments have established that Phaleria macrocarpa contain alkaloids, flavonoids, and saponins. The aim of the research was to find out effect of giving Phaleria macrocarpa fruit extract orally on growth and development of rat (Rattus norvegicus L. fetus during organogenesis period and teratogenic dosage. The Complete Randomized Design (CRD with five treatments group, and each group use five repetitions were used in this study. Phaleria macrocarpa fruit extract was disolved in aquadest and administrated orally on 7th-17th day of pregnancy. The group treated with fruit extract of Phaleria macrocarpa dosage 0; 0.008; 0.017; 0.025; and 0.033 g/200 g BW. At 18th day of pregnancy, rats were sacrificed and caesarian section to remove the fetuses from uterine. Observation on fetuses include: number of living fetus and intrauterine mortality, body weight and length, morphological malformation, structure of skeletal and ossification result. The quantitative data was analysed by analysis of variance and continued with DMRT (Duncan Multiple Range Test. Qualitative data was analysed descriptively. The result of the research showed that Phaleria macrocarpa fruit extract dosage 0.008 g/200 g BW to 0.033 g/200 g BW caused decrease percentage of living fetuses, increase percentage of intrauterine mortality, morphological malformation such as hemoraghe, kinkey and ossification disturbance. Dosage of 0.033 g/200 g BW caused micromelia.

  12. Phaleria macrocarpa reduces glomerular growth factor expression in alloxan-induced diabetic rats

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    Evy Sulistyoningrum

    2013-08-01

    Full Text Available Background Diabetic nephropathy (DN is the most serious complication of diabetes, causing end-stage renal disease throughout the world. Recent studies have reported a direct role of vascular endothelial growth factor (VEGF and transforming growth factor-â (TGF-â in DN pathogenesis. VEGF and TGF-â are expressed early in glomeruli in response to hyperglycemia. Active substances of Phaleria macrocarpa (PM pericarp are known to have nephroprotective effects. This study aimed to evaluate the effects of Phaleria macrocarpa (Scheff. Boerl pericarp extract on VEGF and TGF-â expression in alloxan-induced diabetic rats. Methods An experimental study was conducted on twenty five male albino (Sprague Dawley rats divided into five groups (of five each: normal control; diabetic; diabetic + metformin 100 mg/kgBW; diabetic + methanolic PM extract 250 mg/kgBW; and diabetic + aqueous PM extract 250 mg/kgBW. Diabetes was induced by alloxan monohydrate 150 mg/BW intraperitoneally. Treatment was given for 3 weeks. VEGF and TGF-â expression analysis was performed by means of immunohistochemical technique. Differences between groups were assessed by one-way ANOVA. Results VEGF expression in the PM extract group was significantly lower than that in the diabetic group and even metformin group (p<0.01. TGF-â expression in methanolic PM extract group was significantly lower than in diabetic and metformin group (p<0.01, but aqueous PM extract group only showed significancy when compared with diabetic group (p< 0.01. Conclusions Phaleria macrocarpa pericarp extract reduces glomerular expression of TGF-â and VEGF in alloxan-induced diabetic rats.

  13. Controle de qualidade da raiz de Operculina macrocarpa (Linn) Urb., Convolvulaceae

    OpenAIRE

    Michelin,Daniele Carvalho; Finati,Suellen Cristiane Gandolfo; Sacramento, Luis Vitor Silva [UNESP; Vilegas, Wagner [UNESP; Salgado, Hérida Regina Nunes [UNESP

    2010-01-01

    A qualidade dos fitoterápicos inclui rigoroso acompanhamento das diferentes etapas do desenvolvimento e produção destes produtos, desde a coleta do vegetal até a disponibilidade do produto final. Neste trabalho foi realizado o controle da qualidade do da raiz de Operculina macrocarpa (Linn) Urb., popularmente conhecida como batata-de-purga. Para o controle físicoquímico e microbiológico utilizaram-se metodologias farmacopeicas e não farmacopeicas. Os resultados obtidos mostraram que a raiz ap...

  14. Antimicrobial property and antioxidant composition of crude extracts of Pueraria mirifica, Butea superba and Mucuna macrocarpa

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    Ekachai Chukeatirote

    2009-04-01

    Full Text Available In this study, crude extracts of Pueraria mirifica, Butea superba and Mucuna macrocarpa were prepared using sequential extraction with three different solvents (hexane, ethyl acetate and methanol. The extracts obtained were then used to test for their antimicrobial activity by the disc diffusion method, which showed that, against a wide range of Gram-positive and Gram-negative bacteria, only the P. mirifica extract obtained with ethyl acetate exhibited antimicrobial activities. The minimum inhibitory concentration (MIC of the extract was also determined with values between 15 and 50 mg/ml depending on the microbes tested. Thin layer chromatography (TLC was subsequently used to separate the chemical constituents of the extract. When tested against B. cereus, there were only two bands which showed anti-B. cereus activity. Additionally, the crude extracts of P. mirifica, B. superba and M. macrocarpa were analysed for some antioxidant compounds using HPLC. Our results showed that all the extracts contained daidzin, genistin, daidzein and genistein, all of which were present in the highest amounts (0.045, 0.037, 0.049 and 0.060 % respectively in the ethyl acetate extract of P. mirifica.

  15. Antiproliferative evaluation of terpenoids and terpenoid coumarins from Ferulago macrocarpa (Fenzl Boiss. fruits

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    Seyed-Ebrahim Sajjadi

    2015-01-01

    Full Text Available Background: Ferulago macrocarpa is a plant used as flavoring agent and protectant in the food industry and as a folk medicinal plant in Iran with no available information on its chemical identity. Ferulago spp. showed to contain biologically terpenoids and coumarins. Objective: The objective was to isolate and characterize terpenoids and coumarins from the acetone extract of F. macrocarpa fruits and to evaluate their antiproliferative effects on several cell lines. Materials and Methods: A series of normal and reverse phase gravity and high-performance liquid chromatography analyses were used to purify constituents. Compounds 1-5 and 7 were evaluated for their cytotoxic effects on MCF-7, HT-29 and H-1299 cell lines. Results: Six compounds including bornyl acetate (1, 1,10-di-epi-cubenol (2, stigmasterol (3 and three coumarins grandivittin (4, prantschimgin (5 and 4"-hydroxygrandivittin (7 along with mixtures of feruloyl derivatives (6a-6c have been purified. Their structures were established by spectroscopic methods including nuclear magnetic resonance and MS analyses. Compound 2 showed moderate cytotoxicity effect with IC 50 values of 5.0 and 6.7 mM on MCF-7 and HT-29, respectively. Conclusion: 1,10-di-epi-Cubenol could be considered as a potential proliferation inhibitor of MCF-7 and HT-29 cell lines.

  16. Toxicity of Anadenanthera macrocarpa (Fabaceae: Mimosoideae and Bougainvillea buttiana (Nyctaginaceae extracts to lepidopteran pests

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    Diego Tavares Carvalhinho

    2017-05-01

    Full Text Available http://dx.doi.org/10.5007/2175-7925.2017v30n2p15 For small and medium agricultural production, vegetal extracts are highly efficient at managing pests because they control a wide range of arthropods. The objective of this research was to evaluate the toxic effects of Anadenanthera macrocarpa (Fabaceae: Mimosoideae and Bougainvillea buttiana (Nyctaginaceae extracts on Helicoverpa armigera (Hübner, Spodoptera cosmioides (Walker and Spodoptera frugiperda (Smith (Lepidoptera: Noctuidae. Helicoverpa armigera and S. cosmioides caterpillars were maintained on soybean leaf discs, and S. frugiperda was maintained on corn leaf discs, treated with diluted aqueous extracts at concentrations of 0, 500, 1,000, 2,500, 4,000, 5,000, 10,000 and 15,000 mg.L-1. The lethal and sublethal effects of the extracts on the insects were measured. According to the results, the concentration of 500 mg.L-1 of the A. macrocarpa extract caused the highest percentage of mortality (93.33% of H. armigera. The extract of B. buttiana caused 86.67% and 60% mortality of H. armigera (1,000 mg.L-1 and S. cosmioides (4,000 mg.L-1, respectively. The reduction of the emergence of adults was the main sublethal effect found for S. cosmioides and S. frugiperda. Considering the results, the vegetal extracts used in this research are a potential alternative for the management of lepidopteran pests.

  17. Effects of pre-treatments and temperature on seed viability and germination of Juniperus macrocarpa Sm.

    Science.gov (United States)

    Pinna, Maria Silvia; Mattana, Efisio; Cañadas, Eva Maria; Bacchetta, Gianluigi

    2014-05-01

    The effects of collecting season, collection site, laboratory pre-treatments and temperatures on seed viability and germination of Juniperus macrocarpa were investigated. Ripe cones were collected in four Sardinian dune systems, in two seasons, from plant and soil. Warm (W) and cold (C) stratifications, two combinations of them (W+C, C+W), and no pre-treatment (0) were applied. Seeds were incubated in a range of constant (10-25°C) and an alternating (25/10°C) temperature regime. Seed viability was low (ca. 40%) and varied significantly according to the collecting season. Seed germination was also low (ca. 10%), the 0 and W were the most effective pre-treatments on stimulating germination. The best germination temperature, without any pre-treatment, was 15°C (ca. 20%). J. macrocarpa seeds are dormant and the achieved results suggested that the presence of secondary dormancy is induced by cold stratification. Spring appeared to be the best season for seed collecting, whereas autumn was the best for sowing. These results give new findings for restoration activities on this species. Copyright © 2014. Published by Elsevier SAS.

  18. Population Assessment and Degree of Threat of Chalybea Macrocarpa (Melastomataceae Endemic Specie from Colombia.

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    Pablo Andres Gil

    2014-03-01

    Full Text Available Population assessment results from Chalybea macrocarpa are shown, the specie is considerate ENDANGERED (EN by its restricted area, threatened is generated by crops and extensive cattle farming. The study was conducted in the Boyacá department, municipality of Arcabuco, in three established localities using herbarium and literature information; field work made possible identified distribution, density and phenology like sub criteria, allowing identify the presence extension and occupancy area. We took structural data (height, coverage and DBH to determinate the population age’s classes. Whit the gathered information and the associated vegetation, the specie is re-categorized with the B IUCN criteria. It is distributed to the northwest and southern in Arcabuco, in an area of 59.9 km2, 4 km2  of occupancy and a population density of 73 individual/km2. Flowering and fruiting is continuous through the year, however, most of the flowering is from March to August and fruiting from September to February. Age structure allows identified ten species between seedlings, juveniles and adults. Population is represented by few seedling individuals (10.6 % and juveniles (20.9 % versus adults (68.5 %. Finally, C. macrocarpa is upgraded to Critical Risk (CR B1ab (iii. Evaluación poblacional y grado de amenaza de Chalybea macrocarpa (Melastomataceae especie endémica de ColombiaSe presentan los resultados de la evaluación poblacional de Chalybea macrocarpa, considerada En Peligro (EN por su área de distribución restringida, presión generada por cultivos y ganadería extensiva. El estudio se realizó en el departamento de Boyacá, en el municipio de Arcabuco, en tres localidades establecidas con información de herbario y bibliografía; con trabajo de campo se identificó la distribución, densidad y fenología como subcriterios para delimitar el área de extensión de presencia y de ocupación de la misma. Se tomaron datos estructurales

  19. Evaluation of antioxidant, free radical scavenging and antimicrobial, activity of Quercus incana Roxb.

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    Rizwana eSarwar

    2015-11-01

    Full Text Available Considering the indigenous utilization of Quercus incana Roxb., the present study deals with the investigation of antioxidant, free radical scavenging activity, total phenolic content and antimicrobial activity of Quercus incana Roxb. In vitro antioxidant activity of the plant fractions were determined by DPPH and NO scavenging method. Total phenolic contents were determined by gallic acid equivalent (GAE and antimicrobial activities were determined by agar well diffusion method. It was observed that Quercus incana Roxb. showed significant antibacterial activity against Gram-positive and Gram-negative bacteria. n-Butanol fraction showed maximum activity against Micrococcus leuteus with 19 mm zone of inhibition. n-Butanol fraction of Quercus incana Roxb. showed immense antifungal activity against Aspergillus niger (32 mm ± 0.55 and Aspergillus flavus (28 mm ± 0.45. Similarly n-butanol fraction showed relatively good antioxidant activity with IC50 value of 55.4 ± 0.21μg/mL. The NO scavenging activity of ethyl acetate fraction (IC50 = 23.21 ± 0.31 μg/mL was fairly good compared to other fractions. The current study of Quercus incana Roxb. suggests the presences of synergetic action of some biological active compounds that may be present in the leaves of medicinal plant. Further studies are needed to better characterize the important active constituents responsible for the antimicrobial, antioxidant and free radical scavenging activity.

  20. Separação e identificação de constituintes químicos polares dos galhos de Porcelia Macrocarpa

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    Chaves Mariana H.

    2000-01-01

    Full Text Available This paper describes a methodology to separate and identify polar compounds as flavonoid and lignan glucosides, amino acids, salt of quaternary ammonium amino acid and carbohydrates from branches of Porcelia macrocarpa (Annonaceae.

  1. Growth, ectomycorrhization and biochemical parameters of Quercus ...

    African Journals Online (AJOL)

    daoudi

    2016-09-21

    Sep 21, 2016 ... stomatal conductance and photosynthesis of plants, which changes .... polyphenols were quantified after colorimetric reaction using Folin-. Ciocalteu ..... of different water and light intensities on cork oak (Quercus suber L.).

  2. The taxonomic status of the Mexican oak Quercus undata (Fagaceae, Quercus, Section Quercus El estatus taxonómico del encino mexicano Quercus undata (Fagaceae, Quercus, Sección Quercus

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    Jeffrey R. Bacon

    2011-12-01

    Full Text Available Quercus undata Trel. (Fagaceae, Quercus, Section Quercus has a complex taxonomic and nomenclatural history. Intensive sampling of oaks at the type locality of Q. undata Trel. in Durango, Mexico and evaluation of herbarium specimens and plants in the field indicate that Q. undata represents variation in Quercus chihuahuensis Trel. in white oak communities where introgressive hybridization among Q. chihuahuensis, Q. grisea Liebm., and a third white oak, Q. arizonica Sarg. made species identification difficult. Endlich's type specimen of Q. undata, as designated by Trelease, was apparently destroyed in bombing raids on Berlin during World War II, and we propose herein as lectotype the Trelease illustration of the type. An epitype is also designated in support of the lectotype, given that some features cannot be critically observed on the illustration. The long peduncles of the specimen illustrated by Trelease indicate a close relation to Q. chihuahuensis.Quercus undata Trel. (Fagaceae, Quercus, Section Quercus tiene una compleja historia taxonómica y de nomenclatura. Un muestreo intensivo de los encinos en la localidad tipo de Q. undata en Durango, México y análisis de ejemplares en herbario y en el campo indican que Q. undata representa variación en Q. chihuahuensis Trel. en los sitios donde la hibridación introgresiva entre Q. chihuahuensis, Q. grisea Liebm., y un tercer encino blanco, Q. arizonica Sarg., dificultan la identificación de especies. El ejemplar tipo designado por Trelease aparentemente fue destruido en el bombardeo de Berlín durante la Segunda Guerra Mundial, por lo que se propone como lectotipo a la ilustración del tipo en la obra de Trelease. Se designa también un epitipo dado que algunos rasgos no pueden ser críticamente observados en la ilustración. Los largos pedúnculos del espécimen ilustrado por Trelease indican la relación cercana a Q. chihuahuensis.

  3. EFECTO DIURÉTICO DE LAS HOJAS DE MAYTENUS MACROCARPA “CHUCHUHUASI” EN RATAS ALBINAS

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    Fanny Bastidas Garcia

    2016-07-01

    Full Text Available Objetivo: Evaluar la actividad diurética del extracto acuoso obtenido a partir de la hojas del Maytenus macrocarpa “Chuchuhuasi” en ratas albinas. Material y Métodos: Se utilizaron 68 ratas albinas machos, con pesos medios de 250 g, se empleó el Método de Lipschitz, donde se registró el volumen de orina por hora y total a la sexta hora. Los grupos experimentales fueron: Control (suero fisiológico al 0.9%, chuchuhuasi 1 (250mg/kg, chuchuhuasi 2 (500mg/kg, chuchuhuasi 3 (750mg/kg, hojas de chuchuhuasi 4 (1000mg/kg, furosemida 1 (10mg/kg y furosemida 2 (20mg/kg. Para la validación estadística se usó la prueba de Shapiro-Wilk, Tukey y Dunns. Resultados: El mayor volumen total obtenido durante las primeras 24 horas fue de 5,17ml para chuchuhuasi de 1000 mg/kg, llegando a tener inclusive mayor valor que la furosemida de 20 mg/kg. Por otro lado el grupo de chuchuhuasi de 250 mg/kg (2.32 obtuvo  menor acción diurética que el grupo control (2.55 ml. El test de Tukey no indicó diferencias significativas. Sin embargo, en el análisis bioquímico el test de Xi cuadrado tuvo un p< 0.05 para el PH. Conclusión: Se demuestra una respuesta diurética positiva en todos los niveles de dosis ensayadas del extracto etanólico de Maytenus macrocarpa: 250, 500, 750 y un mayor efecto 1000 mg/kg de peso, al compararlos con el grupo control y la Furosemida. Palabras Clave: Diuresis, Furosemida, Medicina Tradicional, Etnofarmacología.

  4. Responses of evergreen and deciduous Quercus species to enhanced ozone levels

    Energy Technology Data Exchange (ETDEWEB)

    Calatayud, Vicent, E-mail: calatayud_viclor@gva.e [Instituto Universitario CEAM-UMH, Charles R. Darwin 14, Parc Tecnologic, 46980 Paterna, Valencia (Spain); Cervero, Julia; Calvo, Esperanza [Instituto Universitario CEAM-UMH, Charles R. Darwin 14, Parc Tecnologic, 46980 Paterna, Valencia (Spain); Garcia-Breijo, Francisco-Jose [Laboratorio de Anatomia e Histologia Vegetal ' Julio Iranzo' , Jardin Botanico, Universitat de Valencia, c/Quart 80, 46008 Valencia (Spain); Departamento de Ecosistemas Agroforestales, Escuela Tecnica Superior del Medio Rural y Enologia, Universidad Politecnica de Valencia, Avda. Blasco Ibanez 21, 46010 Valencia (Spain); Reig-Arminana, Jose [Departamento de Ecosistemas Agroforestales, Escuela Tecnica Superior del Medio Rural y Enologia, Universidad Politecnica de Valencia, Avda. Blasco Ibanez 21, 46010 Valencia (Spain); Sanz, Maria Jose [Instituto Universitario CEAM-UMH, Charles R. Darwin 14, Parc Tecnologic, 46980 Paterna, Valencia (Spain)

    2011-01-15

    Plants of one evergreen oak (Quercus ilex) and three deciduous oaks (Q. faginea, with small leaves; Q. pyrenaica and Q. robur, with large leaves) were exposed both to filtered air and to enhanced ozone levels in Open-Top Chambers. Q. faginea and Q. pyrenaica were studied for the first time. Based on visible injury, gas exchange, chlorophyll content and biomass responses, Q. pyrenaica was the most sensitive species, and Q. ilex was the most tolerant, followed by Q. faginea. Functional leaf traits of the species were related to differences in sensitivity, while accumulated ozone flux via stomata (POD{sub 1.6}) partly contributed to the observed differences. For risk assessment of Mediterranean vegetation, the diversity of responses detected in this study should be taken into account, applying appropriate critical levels. - Ozone tolerance overlapped with leaf traits in four Quercus species.

  5. Vulnerability of Quercus ilex facing increasing drought: which functional adjustments?

    Science.gov (United States)

    Limousin, Jean-Marc; Rambal, Serge; Misson, Laurent; Ourcival, Jean-Marc; Rocheteau, Alain; Rodriguez, Raquel

    2010-05-01

    In the Mediterranean basin, precipitation is expected to decline as a consequence of climate change, and so will induce summer drought duration and intensity increase. The responses of a Quercus ilex coppice to such a decline in water availability were studied for several years within a throughfall exclusion experiment. This study focuses on the ecophysiological and morphological responses that modify transpiration and productivity. The main mechanisms regulating transpiration under decreasing water availability were assessed: stomatal control, twig and stem hydraulic conductance and leaf area adjustment. The decline of transpiration due to the reduced water availability was mainly driven by a reduced leaf area. In the meantime, other hydraulic traits were not significantly modified by the increased drought severity. The phenotypic plasticity of Quercus ilex leaves yielded some modifications of leaf traits, but with slight concurrent consequences on leaf photosynthesis. The decreased water availability reduced carbon assimilation and, in turn, the primary growth and the starch storage of trees. Finally, none of the several adjustments to the long-term experimentally increased drought was observed to reduce the individual vulnerability to water stress.

  6. Modulation of the Antibiotic Activity by Extracts from Amburana cearensis A. C. Smith and Anadenanthera macrocarpa (Benth. Brenan

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    Fernando G. Figueredo

    2013-01-01

    Full Text Available The aim of this study was to verify the possible interactions between ethanol extracts of Amburana cearensis A. C. Smith and Anadenanthera macrocarpa (Benth. Brenan, combined with six antimicrobial drugs against multiresistant strains of Staphylococcus aureus and Escherichia coli isolated from humans. The antibacterial activity of the extracts was determined using the minimum inhibitory concentration (MIC. The microdilution assay was performed to verify the interactions between the natural products and the antibiotics using a subinhibitory concentration. The activity of amikacin associated with the extract of Anadenanthera macrocarpa against EC 27 was enhanced, demonstrating an MIC reduction from 128 to 4 μg/mL. Among the β-lactams, no potentiation on its activity was observed, with exception to the antagonism of the natural products with ampicillin against S. aureus 358.

  7. Efectos sobre la temperatura, frecuencia respiratoria, frecuencia cardiaca y electrocardiograma de Maytenus macrocarpa (Ruiz & Pav.) Briq. (chuchuhuasi)

    OpenAIRE

    Huaccho Rojas, Juan Jesús; Cavero Aguilar, Evelyn Sally; Quezada Rojas, Melissa Andrea; Lara Paredes, Andrea Mercedes; Lluen Escobar, Silvana Estela; Paragulla Bocángel, Ahmed Alberto; Rojas Villacorta, Fernando Junior; Loja Herrera, Berta; Alvarado Yarasca, Ángel Tito; Mujica Calderón, José; Salazar Granara, Alberto Alcibíades

    2012-01-01

    Introducción: estudios de árboles del género Maytenus, especies forsskaoliana, ilicifolia y krukovii revelan efectos depresores a nivel cardiovascular sobre la presión arterial y frecuencia cardiaca. Objetivos: analizar experimentalmente los efectos de las hojas de Maytenus macrocarpa "chuchuhuasi" sobre la frecuencia cardiaca, patrones electrocardiográficos, frecuencia respiratoria, y temperatura. Métodos: investigación de tipo exploratorio, analítico y experimental. Se uti...

  8. Rapid investigation of α-glucosidase inhibitory activity of Phaleria macrocarpa extracts using FTIR-ATR based fingerprinting

    Directory of Open Access Journals (Sweden)

    Sabina Easmin

    2017-04-01

    Full Text Available Phaleria macrocarpa, known as “Mahkota Dewa”, is a widely used medicinal plant in Malaysia. This study focused on the characterization of α-glucosidase inhibitory activity of P. macrocarpa extracts using Fourier transform infrared spectroscopy (FTIR-based metabolomics. P. macrocarpa and its extracts contain thousands of compounds having synergistic effect. Generally, their variability exists, and there are many active components in meager amounts. Thus, the conventional measurement methods of a single component for the quality control are time consuming, laborious, expensive, and unreliable. It is of great interest to develop a rapid prediction method for herbal quality control to investigate the α-glucosidase inhibitory activity of P. macrocarpa by multicomponent analyses. In this study, a rapid and simple analytical method was developed using FTIR spectroscopy-based fingerprinting. A total of 36 extracts of different ethanol concentrations were prepared and tested on inhibitory potential and fingerprinted using FTIR spectroscopy, coupled with chemometrics of orthogonal partial least square (OPLS at the 4000–400 cm−1 frequency region and resolution of 4 cm−1. The OPLS model generated the highest regression coefficient with R2Y = 0.98 and Q2Y = 0.70, lowest root mean square error estimation = 17.17, and root mean square error of cross validation = 57.29. A five-component (1+4+0 predictive model was build up to correlate FTIR spectra with activity, and the responsible functional groups, such as –CH, –NH, –COOH, and –OH, were identified for the bioactivity. A successful multivariate model was constructed using FTIR-attenuated total reflection as a simple and rapid technique to predict the inhibitory activity.

  9. Crescimento e sobrevivência de Anadenanthera macrocarpa (Benth. Brenan (Leguminosae, em uma área de caatinga, Alagoinha, PE

    Directory of Open Access Journals (Sweden)

    Silva Lucia Maria Bezerra da

    2000-01-01

    Full Text Available O estudo do crescimento e da sobrevivência de Anadenanthera macrocarpa (Benth. Brenan foi realizado na Fazenda Geraldão (8°29'28" S e 36°47'00" W, Alagoinha, PE, no período de julho/1996 a junho/1997. selecionaram-se 10 indivíduos adultos de A. macrocarpa dividindo-se suas copas em quadrantes, e quantificaram-se todos os indivíduos jovens acompanhando crescimento e sobrevivência da estação chuvosa de 1996 até a estação chuvosa de 1997 . A estrutura e distribuição espacial de uma população foi estudada em 10 parcelas de 10m x 10m (1.000m² , subdividida em 250 parcelas de 2m x 2m. Os indivíduos estudados no período de um ano totalizaram 344, sendo 211 jovens e 133 juvenis. A estrutura da população consistiu de 192 indivíduos: 170 jovens (88,5%, oito juvenis (4,2% e 14 adultos (7,3%. A distribuição espacial foi do tipo agregado. A. macrocarpa apresentou-se resistente durante a estação seca, devido ao seu alto índice de sobrevivência (73,3% na área estudada.

  10. Quercus ilex L. carbon sequestration capability related to shrub size.

    Science.gov (United States)

    Gratani, Loretta; Catoni, Rosangela; Varone, Laura

    2011-07-01

    CO(2) sequestration capacity of Quercus ilex L., an evergreen species developing in shrub and forest communities widely distributed in the Mediterranean Basin, was analysed. Experiments were carried out in the period of January to December 2009 on 20 shrubs of different size, growing at the Botanical Garden of Rome. At shrub level, the largest differences concern total photosynthetic leaf surface area per shrub and shrub volume. Shrubs structure significantly contribute to reduce total irradiance and air temperature below the canopy. Leaf mass per area is higher in sun leaves than in shade ones (20 ± 1 and 12 ± 2 mg cm( -2), respectively). Sun leaves are also characterised by the highest leaf thickness (78% higher in sun than in shade leaves), the spongy parenchyma thickness (71% higher in sun than in shade leaves) and the highest adaxial cuticle thickness (7.2 ± 1.2 and 4.7 ± 0.5 μm, respectively). Net photosynthetic rates (P (N)) of sun and shade leaves are the highest in spring, and shade leaves contribute 6% to the whole shrub P (N). Q. ilex CO(2) sequestration depends on shrub size. In particular, the CO(2) sequestration per shrub was 0.20 ± 0.02 Kg CO(2) year( -1) in small shrubs, and it was 75% and 98% lower than in medium and large ones. The highest CO(2) sequestration is measured in spring, decreasing 77% during drought. Q. ilex may play a significant role in mitigating carbon dioxide concentration and lowering air and soil temperature in areas around the Mediterranean Basin.

  11. Estudio cariológico de Quercus humboldtti Bonpl Caryological study of Quercus humboldtii Bonpl

    Directory of Open Access Journals (Sweden)

    Alvarado de Coral Cecilia

    1989-12-01

    Full Text Available Se comprobó que la especie del roble Ouercus humboldtii Bonpl. tiene 2 n= 24 cromosomas, al igual que la mayoría de las especies estudiadas de Quercus. Utilizando pretratamiento y tinción con orceina lactopropiónica fue posible obtener el cariotipo e ideograma.Using lactopropionic orceine for a previus tintion we obtained the Caryotype and ideogram of Quercus humboldtii Bonpl. and we observed that it has 2 n = 24 chromosomes as most studied species of Quercus do.

  12. Drivers of radial growth and carbon isotope discrimination of bur oak (Quercus macrocarpa Michx.) across continental gradients in precipitation, vapour pressure deficit and irradiance

    Science.gov (United States)

    Tree-ring characteristics including stable isotope composition are commonly used to reconstruct climate variables and establish mechanisms that underlie oscillations in modes of climate variability. However, divergence from the assumption of a single, primary biophysical control ...

  13. Quercus petraea in België

    NARCIS (Netherlands)

    Rompaey, van E.

    1957-01-01

    Naar aanleiding van het artikel over Quercus petraea in het Corr. bl. no. 4 zend ik u hierbij een kopie van de Belgische verspreidingskaart, omdat daar m.i. wel een en ander uit af te leiden is, dat ook Nederland aanbelangt: 1. Bij bet massale verspreidingsgebied ten Z. van de lijn Samber-Maas (de l

  14. Quercus kelloggii Newb., California black oak

    Science.gov (United States)

    P.M. McDonald

    1990-01-01

    California black oak (Quercus kelloggii) exceeds all other California oaks in volume, distribution, and altitudinal range. Yet this deciduous hardwood has had little sustained commercial use and almost no management, even though its wood closely resembles that of its valuable, managed, and heavily used counterpart-northern red oak (...

  15. Chemosystematic value of flavonoids from Crataegus x macrocarpa (Rosaceae) with special emphasis on (R)- and (S)-eriodictyol-7-O-glucuronide and luteolin-7-O-glucuronide.

    Science.gov (United States)

    Ringl, Alexandra; Prinz, Sonja; Huefner, Antje; Kurzmann, Michael; Kopp, Brigitte

    2007-02-01

    The chemotaxonomic investigation of Crataegus x macrocarpa, a hybrid of C. laevigata and C. rhipidophylla, presents the qualitative and quantitative composition of its flavonoid pattern in relationship to its parent species for the first time. Six flavonoids were identified as vitexin-2''-O-rhamnoside (1), vitexin (2), isovitexin (3), rutin (4), hyperoside (5), and isoquercitrin (6). Furthermore, two flavonoids were isolated from C. x macrocarpa and identified as a diastereoisomeric mixture of (R)- and (S)-eriodictyol-7-O-beta-D-glucuronide (7) and luteolin-7-O-beta-D-glucuronide (8) by means of 1D- and 2D-NMR, MS, and UV experiments. Compounds 7 and 8 were isolated for the first time from Crataegus species. While missing in C. laevigata, their occurrence in C. rhipidophylla additionally emphasizes its chemotaxonomic relationship to C. x macrocarpa.

  16. Antiproliferative and Antiestrogenic Activities of Bonediol an Alkyl Catechol from Bonellia macrocarpa

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    Rosa Moo-Puc

    2015-01-01

    Full Text Available The purpose of this study was to investigate antiproliferative activity of bonediol, an alkyl catechol isolated from the Mayan medicinal plant Bonellia macrocarpa. Bonediol was assessed for growth inhibition of androgen-sensitive (LNCaP, androgen-insensitive (PC-3, and metastatic androgen-insensitive (PC-3M human prostate tumor cells; toxicity on normal cell line (HEK 293 was also evaluated. Hedgehog pathway was evaluated and competitive 3H-estradiol ligand binding assay was performed. Additionally, antioxidant activity on Nrf2-ARE pathway was evaluated. Bonediol induced a growth inhibition on prostate cancer cell lines (IC50 from 8.5 to 20.6 µM. Interestingly, bonediol binds to both estrogen receptors (ERα (2.5 µM and ERβ (2.1 µM and displaces the native ligand E2 (17β-estradiol. No significant activity was found in the Hedgehog pathway. Additionally, activity of bonediol on Nrf2-ARE pathway suggested that bonediol could induce oxidative stress and activation of detoxification enzymes at 1 µM (3.8-fold. We propose that the compound bonediol may serve as a potential chemopreventive treatment with therapeutic potential against prostate cancer.

  17. Antitrypanosomal Acetylene Fatty Acid Derivatives from the Seeds of Porcelia macrocarpa (Annonaceae

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    Luciana de Á. Santos

    2015-05-01

    Full Text Available Chagas’ disease is caused by a parasitic protozoan and affects the poorest population in the world, causing high mortality and morbidity. As a result of the toxicity and long duration of current treatments, the discovery of novel and more efficacious drugs is crucial. In this work, the hexane extract from seeds of Porcelia macrocarpa R.E. Fries (Annonaceae displayed in vitro antitrypanosomal activity against trypomastigote forms of T. cruzi by the colorimetric MTT assay (IC50 of 65.44 μg/mL. Using chromatographic fractionation over SiO2, this extract afforded a fraction composed by one active compound (IC50 of 10.70 µg/mL, which was chemically characterized as 12,14-octadecadiynoic acid (macrocarpic acid. Additionally, two new inactive acetylene compounds (α,α'-dimacro-carpoyl-β-oleylglycerol and α-macrocarpoyl-α'-oleylglycerol were also isolated from the hexane extract. The complete characterization of the isolated compounds was performed by analysis of NMR and MS data as well as preparation of derivatives.

  18. Antitrypanosomal Acetylene Fatty Acid Derivatives from the Seeds of Porcelia macrocarpa (Annonaceae).

    Science.gov (United States)

    de Á Santos, Luciana; Cavalheiro, Alberto J; Tempone, Andre G; Correa, Daniela S; Alexandre, Tatiana R; Quintiliano, Natalia F; Rodrigues-Oliveira, André F; Oliveira-Silva, Diogo; Martins, Roberto Carlos C; Lago, João Henrique G

    2015-05-07

    Chagas' disease is caused by a parasitic protozoan and affects the poorest population in the world, causing high mortality and morbidity. As a result of the toxicity and long duration of current treatments, the discovery of novel and more efficacious drugs is crucial. In this work, the hexane extract from seeds of Porcelia macrocarpa R.E. Fries (Annonaceae) displayed in vitro antitrypanosomal activity against trypomastigote forms of T. cruzi by the colorimetric MTT assay (IC50 of 65.44 μg/mL). Using chromatographic fractionation over SiO2, this extract afforded a fraction composed by one active compound (IC50 of 10.70 µg/mL), which was chemically characterized as 12,14-octadecadiynoic acid (macrocarpic acid). Additionally, two new inactive acetylene compounds (α,α'-dimacro-carpoyl-β-oleylglycerol and α-macrocarpoyl-α'-oleylglycerol) were also isolated from the hexane extract. The complete characterization of the isolated compounds was performed by analysis of NMR and MS data as well as preparation of derivatives.

  19. Large-scale patterns of Quercus ilex, Quercus suber, and Quercus pyrenaica regeneration in central-western Spain

    DEFF Research Database (Denmark)

    Plieninger, Tobias; Rolo, Víctor; Moreno, Gerardo

    2010-01-01

    categories, from small seedlings to large saplings, and for the three oak species studied, especially the evergreens. Of the Quercus ilex, Q. suber, and Q. pyrenaica plots studied, 49%, 62%, and 20% were lacking any small seedlings, and 82%, 96%, and 56% did not have any large saplings, respectively......In Central-Western Spain, forests and woodlands composed of Quercus sp. support outstanding levels of biodiversity, but there is increasing concern about their long-term persistence due to a lack of regeneration. We hypothesize that this regenerative lack is operating on a large geographic scale...... and Q. suber were positively correlated with all understory variables, suggesting that the presence of pioneer shrubs represent a major safe site for early tree recruitment, independent from specific shrub species. © 2010 Springer Science+Business Media, LLC....

  20. Transcriptome Analysis of Beta macrocarpa and Identification of Differentially Expressed Transcripts in Response to Beet Necrotic Yellow Vein Virus Infection.

    Directory of Open Access Journals (Sweden)

    Huiyan Fan

    Full Text Available Rhizomania is one of the most devastating diseases of sugar beet. It is caused by Beet necrotic yellow vein virus (BNYVV transmitted by the obligate root-infecting parasite Polymyxa betae. Beta macrocarpa, a wild beet species widely used as a systemic host in the laboratory, can be rub-inoculated with BNYVV to avoid variation associated with the presence of the vector P. betae. To better understand disease and resistance between beets and BNYVV, we characterized the transcriptome of B. macrocarpa and analyzed global gene expression of B. macrocarpa in response to BNYVV infection using the Illumina sequencing platform.The overall de novo assembly of cDNA sequence data generated 75,917 unigenes, with an average length of 1054 bp. Based on a BLASTX search (E-value ≤ 10-5 against the non-redundant (NR, NCBI protein, Swiss-Prot, the Gene Ontology (GO, Clusters of Orthologous Groups of proteins (COG and Kyoto Encyclopedia of Genes and Genomes (KEGG databases, there were 39,372 unigenes annotated. In addition, 4,834 simple sequence repeats (SSRs were also predicted, which could serve as a foundation for various applications in beet breeding. Furthermore, comparative analysis of the two transcriptomes revealed that 261 genes were differentially expressed in infected compared to control plants, including 128 up- and 133 down-regulated genes. GO analysis showed that the changes in the differently expressed genes were mainly enrichment in response to biotic stimulus and primary metabolic process.Our results not only provide a rich genomic resource for beets, but also benefit research into the molecular mechanisms of beet- BNYV Vinteraction.

  1. Drought-induced photosynthetic inhibition and autumn recovery in two Mediterranean oak species (Quercus ilex and Quercus suber).

    Science.gov (United States)

    Vaz, M; Pereira, J S; Gazarini, L C; David, T S; David, J S; Rodrigues, A; Maroco, J; Chaves, M M

    2010-08-01

    Responses of leaf water relations and photosynthesis to summer drought and autumn rewetting were studied in two evergreen Mediterranean oak species, Quercus ilex spp. rotundifolia and Quercus suber. The predawn leaf water potential (Ψ(lPD)), stomatal conductance (gs) and photosynthetic rate (A) at ambient conditions were measured seasonally over a 3-year period. We also measured the photosynthetic response to light and to intercellular CO₂ (A/PPFD and A/C(i) response curves) under water stress (summer) and after recovery due to autumn rainfall. Photosynthetic parameters, Vc(max), J(max) and triose phosphate utilization (TPU) rate, were estimated using the Farquhar model. RuBisCo activity, leaf chlorophyll, leaf nitrogen concentration and leaf carbohydrate concentration were also measured. All measurements were performed in the spring leaves of the current year. In both species, the predawn leaf water potential, stomatal conductance and photosynthetic rate peaked in spring, progressively declined throughout the summer and recovered upon autumn rainfall. During the drought period, Q. ilex maintained a higher predawn leaf water potential and stomatal conductance than Q. suber. During this period, we found that photosynthesis was not only limited by stomatal closure, but was also downregulated as a consequence of a decrease in the maximum carboxylation rate (Vc(max)) and the light-saturated rate of photosynthetic electron transport (J(max)) in both species. The Vc(max) and J(max) increased after the first autumnal rains and this increase was related to RuBisCo activity, leaf nitrogen concentration and chlorophyll concentration. In addition, an increase in the TPU rate and in soluble leaf sugar concentration was observed in this period. The results obtained indicate a high resilience of the photosynthetic apparatus to summer drought as well as good recovery in the following autumn rains of these evergreen oak species.

  2. Grandivittin as a natural minor groove binder extracted from Ferulago macrocarpa to ct-DNA, experimental and in silico analysis.

    Science.gov (United States)

    Ahmadi, F; Valadbeigi, S; Sajjadi, S E; Shokoohinia, Y; Azizian, H; Taheripak, G

    2016-10-25

    Ferulago macrocarpa (Fenzl) Boiss., is an endemic medicinal herb of Iran. In this study a dihydrofuranocoumarin called grandivittin (GRA) was separate and purified from Ferulago macrocarpa (Fenzl) Boiss, and characterized by (1)H NMR and Mass spectroscopic methods. The electrochemical behavior of GRA was evaluated by cyclic voltammetry (CV). The interaction of GRA with calf thymus double strand deoxyribonucleic acid (ct-DNA), was evaluated by CV, differential pulse voltammetry (DPV), fluorescence, UV-Vis, FT-IR and molecular modeling methods. The thermodynamic parameters of GRA-DNA complex were measured and reported as: ΔH = 15.04 kJ mol(-1), ΔS = 105.54 J mol(-1) and ΔG = -15.62 kJ mol(-1). Docking simulation was performed to investigate the probable binding mode of GRA to various DNA, too. The polymerase extension study was performed using real-time PCR to confirm the inhibitory effect of GRA on polymerase extension activity as a mirror of binding to ct-DNA. However, all data showed that the grooves binding especially minor groove between GRA and ct-DNA is more predominant rather than other binding modes.

  3. BRINE SHRIMP LETHALITY TEST (BSLT DARI BERBAGAI FRAKSI EKSTRAK DAGING BUAH DAN KULIT BIJI MAHKOTA DEWA (Phaleria macrocarpa

    Directory of Open Access Journals (Sweden)

    Vivi Lisdawati

    2012-10-01

    Full Text Available Biological activity of a natural product involved in several certain characteristics will influence its pharmaceutical application. Secondary metabolites, considered as chemical compounds, are now thought to mediate plant defense mechanism by providing chemical barriers against animal and microbial predators. Brine Shrimp Lethality Test (BSLT method has been used as preliminary test for screening the activity of chemical compounds in n­ hexane, ethyl acetate, and methanol extracts from mesocarp and seeds of Phaleria macrocarpa, fam. Thymelaeaceae. BSLT method used shrimp larvas of Artemia salina L. to study the mortality effect that was caused by the sample extracts. All of crude extracts showed bioactivity with LC50 values from 0.16 to 11.83 µg/ml (baseline 1000 µg/ml. It means, at the concentration the crude extracts can cause 50% mortality of A. salina L. shrimp larvas, after 24 hours incubation. These results clearly indicate that crude extracts of P. macrocarpa showed high potential biological activity.

  4. New Secondary Metabolites from Quercus coccifera L.

    Directory of Open Access Journals (Sweden)

    Didem Şöhretoğlu

    2014-07-01

    Full Text Available Three new secondary metabolites kermesoside (1, cocciferoside (2 and (--8-chlorocatechin (3, were isolated from the the stems with barks of Quercus coccifera along with five known phenolic compounds, 3-hydroxy-1-(4-hydroxy-3-methoxyphenyl-propan-1-one (4 and 3-hydroxy-1-(4-hydroxy-3,5-dimethoxyphenyl-propan-1-one (5, trans-resveratrol-3-O-β-glucopyranoside (6 lyoniresinol-9-O-β-xylopyranoside (7, lyoniresinol-9-O-β-glucopyranoside (8. The structure elucidation of the isolated compounds was performed by spectroscopic methods (UV, 1D- and 2D- NMR and HR-MS.

  5. Cork Oak Trees (Quercus suber L.).

    Science.gov (United States)

    Alvarez, Rubén; Toribio, Mariano; Cortizo, Millán; Ordás Fernández, Ricardo-Javier

    2006-01-01

    A transformation system for selected mature Quercus suber L. trees using Agrobacterium tumefaciens has been established. Embryos obtained from recurrent proliferating embryogenic masses are inoculated with AGL1 strain harbouring the plasmid pBINUbiGUSint, which carries the nptII and uidA genes. Evidence of stable transgene integration is obtained by polymerase chain reaction for nptII and uidA genes, Southern blotting and expression of the uidA gene. The transgenic embryos are germinated and successfully transferred to soil.

  6. Temperature stress effects in Quercus suber leaf metabolism.

    Science.gov (United States)

    Chaves, Inês; Passarinho, José António P; Capitão, Cláudio; Chaves, Maria Manuela; Fevereiro, Pedro; Ricardo, Cândido P P

    2011-10-15

    Based on projections that climate changes are will intensify in the near future, it is important to understand how plants respond to climate. Consequently, we have been studying the effect of contrasting temperatures on leaf metabolism of Quercus suber, an important Mediterranean oak. Potted plants were grown under controlled conditions for 53 days at 28°C or 10°C. The accumulation of major soluble metabolites was analyzed by NMR. The relative levels of transcripts of genes encoding key enzymes of the shikimate and phenylpropanoid pathway (CS, PAL, CAD and ChS) were examined by means of quantitative, real-time RT-PCR. At 10°C, in the pre-existing leaves, the concentrations of sucrose, quercitol and catechin were higher, as were PAL and ChS transcripts. At 28°C, however, it was the concentration of quinic acid that was higher, as were the concentrations of CS and CAD transcripts. We conclude that contrasting temperatures greatly influence Q. suber metabolism and that a deeper analysis of the effects of more extreme temperatures is needed to understand the possible effects of temperature changes on Q. suber metabolism and physiology.

  7. Physiological Responses to Prolonged Drought Differ Among Three Oak (Quercus) Species

    Science.gov (United States)

    Cooper, C. E.; Moore, G. W.; Vogel, J. G.; Muir, J. P.

    2015-12-01

    The physiological response of plants to water stress provides insights into which species may survive in exceptional drought conditions. This study conducted on a remnant post oak savanna site in College Station, Texas, examined how drought affected the physiology of three native oak species. In June 2014, after a period of equal watering, we subjected three year old Quercus shumardii (Shumard oak; SO), Q. virginiana (live oak; LO), and Q. macrocarpa (bur oak; BO) saplings to one of two watering treatments: 1) watered, receiving the equivalent of theaverage precipitation rate and 2) droughted, receiving a 100% reduction in precipitation. We measured predawn (ΨPD) and midday (ΨMD) leaf water potential; midday gas exchange (MGE) parameters including photosynthesis (Al), transpiration (T), stomatal conductance (gsw); and leaf soluble (SS) and non-soluble sugar (NSS) concentrations monthly between June and October 2014. Drought stress responses were evident after only one month of induced drought. Droughted saplings showed reduced ΨPD, ΨMD, and MGE (P ≤ 0.05) in comparison to watered saplings of the same species. LO saplings exhibited greater MGE (P ≤ 0.05) while maintaining similar LWP to their respective watered and droughted BO and SO counterparts. Droughted LO exhibited MGE rates similar to those of watered BO and SO (P ≤ 0.05), while watered LO adjusted its MGE rates to changes in water availability better than BO and LO during short-term drought. Compared to water saplings, droughted saplings had greater leaf SS (P = 0.08) and lower NSS concentrations (P = 0.10), possibly due to the conversion of NSS to SS and other simple compounds and reduced consumption of SS for growth by the droughted saplings. Although SO and BO exhibited similar photosynthesis rates, leaf total sugar (SS+NSS) concentration was greater in SO (P ≤ 0.05). By displaying the greatest average photosynthesis rate (P ≤ 0.05), LO should have accumulated the greatest amount of carbon

  8. Phytochemical and toxicity evaluation ofPhaleria macrocarpa (Scheff.) Boerl by MCF-7 cell line and brine shrimp lethality bioassay

    Institute of Scientific and Technical Information of China (English)

    Abul Kalam Azad; Wan Mohd Azizi Wan Sulaiman; Nushrat Khan Sunzida

    2016-01-01

    Objective:To evaluate the cytotoxicity ofPhaleria macrocarpa fruits extracts. Methods: The cytotoxicity test was carried out byin vitroMCF-7 cell line andin vivo brine shrimp lethality bioassay. Results: The preliminary phytochemical test showed the presence of alkaloids, carbohydrate, glycosides, saponin, terpene, steroids, phenols and flavonoids. TheMTT-assay results showed that the highest percentage of cell viability was 106.23% at concentration of 1.25µL and the lowest percentage was 13.04% at concentration of 10µL. Conclusions:TheMTT-assay and brine shrimp lethality bioassay results showed that the extract was non-toxic and it would be consumable as a herbal remedy.

  9. Effect of Butanol Extract of Maturated Mahkota Dewa (Phaleria macrocarpa Fruit on Liver Tissue of Mice (Mus musculus

    Directory of Open Access Journals (Sweden)

    ARIF SOEKSMANTO

    2006-10-01

    Full Text Available Mahkota dewa (Phaleria macrocarpa [Scheff.] Boerl. is a poisonous plant, but almost all parts of the plants can be used as a traditional medicine. Consuming the plant directly can cause swollen, sprue, numb at tongue, fever, even unconscious. Although the plant can conquere various diseases, from diabetes mellitus, hemorrhoid, impotency to cancer, but research on the plant is still limited. A research was conducted to find out effect of subchronic dosage of butanol extract of maturated mahkota dewa fruit. Observation was carried out on liver tissue which is main organ detoxifying poison in the body. Dosage of butanol extract of 0; 42,5; 85 and 170 mg/kg body weight was administered intra peritoneally to mice. The result showed that butanol extract of maturated mahkota dewa fruit did not affect liver tissue, although at dosage 170 mg/kg body weight, a vacuolization on liver's tissue, was occurred.

  10. The Exotic Plants of Indonesia: Mahkota Dewa (Phaleria macrocarpa, Sikaduduak (Melastoma malabathricum Linn and Mengkudu (Morinda citrifolia as Potent Antioxidant Sources

    Directory of Open Access Journals (Sweden)

    Tuty Anggraini

    2015-04-01

    Full Text Available The present study aims to determine the antioxidant activity of of three unique plants from Indonesia used for medicine of dried and etahnolic extract. Plants that are commonly used as medicine is Phaleria macrocarpa known as mahkota dewa (In West Sumatra, Melastoma malabathricum known as sikaduduak and Morinda citrifolia known as mengkudu. The DPPH methods used to the antioxidant assay. The dried Melastoma malabathricum dried and ethanolic extract shows the highest antioxidant activity than Phaleria macrocarpa and Morinda citrifolia both powder  and ethanolic extract. Started from 0,125mg/L for PMm and 0,25mg/L for PPm can be used for antioxidant measurement with DPPH.

  11. A full-length infectious clone of beet soil-borne virus indicates the dispensability of the RNA-2 for virus survival in planta and symptom expression on Chenopodium quinoa leaves.

    Science.gov (United States)

    Crutzen, François; Mehrvar, Mohsen; Gilmer, David; Bragard, Claude

    2009-12-01

    For a better understanding of the functionality and pathogenicity of beet soil-borne virus (BSBV), full-length cDNA clones have been constructed for the three genomic RNAs. With the aim of assessing their effectiveness and relative contribution to the virus housekeeping functions, transcripts were inoculated on Chenopodium quinoa and Beta macrocarpa leaves using five genome combinations. Both RNAs-1 (putative replicase) and -3 (putative movement proteins) proved to be essential for virus replication in planta and symptom production on C. quinoa, whereas RNA-2 (putative coat protein, CP, and a read-through domain, RT) was not. No symptoms were recorded on B. macrocarpa, but viral RNAs were detected. In both host plants, the 19 kDa CP was detected by Western blotting as well as a 115 kDa protein corresponding to the CP-RT.

  12. Phylogeographical Variation of Chloroplast DNA in Cork Oak (Quercus suber)

    OpenAIRE

    Lumaret, Roselyne; TRYPHON-DIONNET, MATHIEU; MICHAUD, HENRI; SANUY, AURÉLIE; IPOTESI, EMILIE; Born, Céline; MIR, CÉLINE

    2005-01-01

    • Background and Aims In the last decades, the geographical location of the centre of origin of Quercus suber (cork oak), a strictly western Mediterranean oak species, has been the subject of controversy.

  13. Quercus cerris extracts limit Staphylococcus aureus biofilm formation

    Science.gov (United States)

    Hobby, Gerren H.; Quave, Cassandra L.; Nelson, Katie; Compadre, Cesar M.; Beenken, Karen E.; Smeltzer, Mark S.

    2012-01-01

    Ethnopharmacological relevance Quercus cerris L., Fagaceae has been used in traditional Mediterranean medicine for numerous purposes, including anti-infective therapies for diarrhea and wound care. Aim of the study To evaluate the anti-staphylococcal activity of fractions of ethanolic extracts of Q. cerris leaf and stem/fruit samples in models for biofilm and growth inhibition. Materials and methods Ethanolic extracts of Q. cerris leaves and stems/fruits were prepared, resuspended in water and fractioned by successively partitioning with hexane, ethyl acetate and butanol. The ability of the fractions to inhibit Staphylococcus aureus biofilm formation was tested using static crystal violet staining methods and confocal laser scanning microscopy. Growth studies were conducted to determine if the diminished capacity to form a biofilm was related to growth inhibition. Results The butanol extracts of both the leaf and stem/fruit samples were the most active, and at a dose of 200 μg/ml, the capacity to form a biofilm was limited to a level equivalent to that of the sarA mutant controls. Further examination of the impact of these fractions on S. aureus growth revealed that biofilm inhibition by the leaf butanol fraction was due to its bacteriostatic activity. The stem/fruit butanol fraction, however, showed a limited impact on growth, thus demonstrating that biofilm inhibition in this case is not related to the bacteriostatic activity of the extract. Conclusion Our evaluation of a medicinal plant used in Mediterranean ethnotherapies for infectious disease has demonstrated significant activity in the inhibition of staphylococcal biofilm formation with a mechanism unrelated to staphylococcal growth inhibition. These results contribute towards validation of this botanical remedy and form the groundwork for future studies in the search for novel biofilm inhibiting drugs. PMID:23127649

  14. Fractal dimension does not adequately describe the complexity of leaf margin in seedlings of Quercus species

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    Camarero, Jesús Julio

    2002-06-01

    Full Text Available We quantified the complexity of leaf margin in a set of Quercus tree species using fractal dimension estimated by the box-counting method (FDb. Leaves were sampled from seedlings in a set of 15 Quercus species with a wide range of leaf morphology (Q. agrifolia, Q. alba, Q. cerris, Q. chrysolepis, Q. coccifera, Q.faginea, Q. frainetto, Q. ilex subsp. ballota, Q. ilex subsp. ilex, Q. petraea, Q. pyrenaica, Q. robur, Q. rubra, Q. suber, and Q. velutina. To describe leaf-edge roughness, we used simple indices: P/L - the ratio of leaf perimeter (P to maximum leaf length (L along the main nerve; P/A - the ratio of leaf perimeter to leaf-blade area (A and its dimensionless version (P/A0'; and WM/Wm -the ratio of maximum distance from the lobe tip to the main nerve (WM to minimum distance from the lobe incision to the main nerve (Wm. There was a strong positive relationship between FDb and P/A. Clustering analysis revealed the existence of three groups of leaves, namely those with: smooth or spiny margins (e.g., Q. coccifera, Q. velutina, shallow lobes (e.g., Q. petraea, and deep lobes (e.g., Q. pyrenaica. In the studied Quercus species, the ratio WM/Wm is a simple and suitable leaflobation index. It is suggested that the flux rate along the leaf edge is related to the complexity of this boundary.Se ha cuantificado la complejidad del margen de las hojas de varias especies arboreas del genero Quercus utilizando la dimension fractal estimada mediante el modo del recuento de cajas (FDb. Se tomaron hojas procedentes de plantulas pertenecientes a 15 especies de Quercus con un amplio rango de morfologfa foliar (Q. agrifolia, Q. alba, Q. cerris, Q. chrysolepis, Q. coccifera, Q. faginea, Q. frainetto, Q. ilex subsp. ballota, Q. ilex subsp. ilex, Q. petraea, Q. pyrenaica, Q. robur, Q. rubra, Q. suber y Q. velutina. Se usaron varios Indices sencillos para describir la complejidad del borde de la hoja: P/L, la relation entre el perimetro foliar (P y la longitud

  15. Taking Leave?

    CERN Multimedia

    2000-01-01

    Planning a holiday? Then if you're a member of the personnel, you'll need to use the Laboratory's new leave system that will be put in place on 1 October. Leave allocations don't change - you are entitled to just as much holiday as before - but instead of being credited annually, your leave will be credited on a monthly basis, and this information will be communicated on your salary slip. The reason for the change is that with the various new leave schemes such as Recruitment by Saved Leave (RSL) and the Progressive Retirement Programme (PRP), a streamlined procedure was required for dealing with all kinds of leave. In the new system, each member of the personnel will have leave accounts to which leave will be credited monthly from the payroll and debited each time an absence is registered in the CERN Electronic Document Handling system (EDH). Leave balances will appear on monthly pay slips, and full details of leave transactions and balances will be available through EDH at all times. As the leave will be c...

  16. EVALUACIÓN POBLACIONAL Y GRADO DE AMENAZA DE Chalybea macrocarpa (MELASTOMATACEAE ESPECIE ENDÉMICA DE COLOMBIA

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    PABLO ANDRÉS GIL-LEGUIZAMÓN

    2014-01-01

    Full Text Available Se presentan los resultados de la evaluación poblacional de Chalybea macrocarpa, considerada En Peligro (EN por su área de distribución restringida, presión generada por cultivos y ganadería extensiva. El estudio se realizó en el departamento de Boyacá (Colombia, en el municipio de Arcabuco, en tres localidades establecidas con información de herbario y bibliografía; con trabajo de campo se identificó la distribución, densidad y fenología como subcriterios para delimitar el área de extensión de presencia y de ocupación de la misma. Se tomaron datos estructurales (altura, cobertura y DAP para determinar las clases de edades de la población. Con la información recopilada y de vegetación asociada, se re-categorizó la especie bajo el criterio B de la UICN. Se distribuye hacia el noroccidente y sur de Arcabuco, en un área de extensión de 59,9 km2, de ocupación 4 km2, y una densidad poblacional de 50 individuos/km2. La floración y fructificación es continua en el año, sin embargo, la mayor floración es de marzo a agosto y la fructificación de septiembre a febrero. La estructura por edades, permitió identificar diez clases entre plántulas, juveniles y adultos. La población está representada por pocos individuos de plántulas (10,6 % y juveniles (20,9 %, comparado con adultos (68,5 %. Finalmente, dadas las condiciones actuales de la población de C. macrocarpa se propone la recategorización del riesgo de extinción En Peligro Crítico (CR B1ab (iii.

  17. Photosynthesis of Quercus suber is affected by atmospheric NH3 generated by multifunctional agrosystems.

    Science.gov (United States)

    Pintó-Marijuan, Marta; Da Silva, Anabela Bernardes; Flexas, Jaume; Dias, Teresa; Zarrouk, Olfa; Martins-Loução, Maria Amélia; Chaves, Maria Manuela; Cruz, Cristina

    2013-12-01

    Montados are evergreen oak woodlands dominated by Quercus species, which are considered to be key to biodiversity conservation and ecosystem services. This ecosystem is often used for cattle breeding in most regions of the Iberian Peninsula, which causes plants to receive extra nitrogen as ammonia (NH(3)) through the atmosphere. The effect of this atmospheric NH(3) (NH(3atm)) on ecosystems is still under discussion. This study aimed to evaluate the effects of an NH(3atm) concentration gradient downwind of a cattle barn in a Montado area. Leaves from the selected Quercus suber L. trees along the gradient showed a clear influence of the NH(3) on δ(13)C, as a consequence of a strong limitation on the photosynthetic machinery by a reduction of both stomatal and mesophyll conductance. A detailed study of the impact of NH(3atm) on the photosynthetic performance of Q. suber trees is presented, and new mechanisms by which NH(3) affects photosynthesis at the leaf level are suggested.

  18. Flower Bud Differentiation in Quercus suber L.

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    Maria Carolina Varela

    2016-06-01

    Full Text Available Background and Purpose: Cork oak (Quercus suber L. is one of the most important forest species growing in the Western Mediterranean region. This investigation intends to assess the timing of flowering differentiation of cork oak and contribute to the deepening of the knowledge about the process of the sexual reproduction of the species. Materials and Methods: In 2010 four trees were selected (9, 14, 24, 25 from a plot of 25 trees located at Quinta da Serra, Portugal. A total of 240 buds were collected from these four trees, on three days (8, 14 and 23 March, from 4 branches per tree and 5 positions per branch for the assessment of meristem differentiation. Results: Meristem differentiation analysed on the sampling days revealed there were only vegetative structures by 8 March; a few male and female primordia on 14 March; and fully differentiated reproductive structures on 23 March. Conclusions: Flowering sex determination of cork oak occurs about one month before the flowering onset.

  19. AKTIVITAS ANTIPROLIFERASI ISOLAT 4 EKSTRAK PETROLEUM ETER DAUN Phaleria macrocarpa (Scheff. Boerl. PADA SEL KANKER SERVIKS MANUSIA (HeLa

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    Dwi Utami

    2011-11-01

    Full Text Available Kanker serviks merupakan penyebab kematian kedua wanita di Indonesia setelah kanker payudara. Mahkota dewa Phaleria macrocarpa (Scheff. Boerl telah dikenal oleh masyarakat dan digunakan secara tradisional untuk pengobatan kanker. Ekstrak petroleum eter daun mahkota dewa menunjukkan aktivitas antiproliferasi pada sel kanker serviks manusia (HeLa dengan IC50 9 µg/ml (Kintoko dan Hawariah, 2007. Tujuan penelitian ini untuk mengetahui aktivitas antiproliferasi isolat 4 ekstrak petroleum eter terhadap sel kanker serviks manusia (HeLa. Serbuk daun mahkota dewa disokletasi dengan petroleum eter, kemudian difraksi dengan etil asetat hingga diperoleh fraksi etil asetat. Fraksi etil asetat dilakukan kromatografi preparatif dengan fase gerak heksana : etil asetat (9:1. Aktivitas antiproliferasi terhadap sel HeLa ditetapkan harga LC50dan doubling time melalui uji sitotoksik dan pengamatan kinetika proliferasi dengan metode MTT. Hasil isolasi dengan kromatografi preparatif diperoleh lima isolat masing-masing dengan harga Rf : 0,05 ; 0,10 ; 0,20 ; 0,60 ; dan 0,90. Harga LC50 dari isolat 4 adalah sebesar 82,091 µg/ml. Isolat 4 menunjukkan penghambatan pertumbuhan sel HeLa dengan memperpanjang doubling time (16,495 jam dibanding kontrol sel (10,170 jam.

  20. The diversification of terpene emissions in Mediterranean oaks: lessons from a study of Quercus suber, Quercus canariensis and its hybrid Quercus afares.

    Science.gov (United States)

    Welter, Saskia; Bracho-Nuñez, Araceli; Mir, Céline; Zimmer, Ina; Kesselmeier, Jürgen; Lumaret, Roselyne; Schnitzler, Jörg-Peter; Staudt, Michael

    2012-09-01

    Interspecific gene flow is common in oaks. In the Mediterranean, this process produced geographical differentiations and new species, which may have contributed to the diversification of the production of volatile terpenes in the oak species of this region. The endemic North African deciduous oak Quercus afares (Pomel) is considered to be a stabilized hybrid between the evergreen Quercus suber (L.) and the deciduous Quercus canariensis (Willd.), presumably being monoterpene and isoprene emitters, respectively. In a common garden experiment, we examined the terpene emission capacities, terpene synthase (TPS) activities and nuclear genetic markers in 52 trees of these three oak species. All but one of the Q. suber and Q. canariensis trees were found to be genetically pure, whereas most Q. afares trees possessed a mixed genotype with a predominance of Q. suber alleles. Analysis of the foliar terpene emissions and TPS activities revealed that all the Q. canariensis trees strongly produced isoprene while all the Q. suber trees were strong monoterpene producers. Quercus afares trees produced monoterpenes as well but at more variable and significantly lower rates, and with a monoterpene pattern different than that observed in Q. suber. Among 17 individuals tested, one Q. afares tree emitted only an insignificant amount of terpenes. No mixed isoprene/monoterpene emitter was detected. Our results suggest that the capacity and pattern of volatile terpene production in Algerian Q. afares populations have strongly diverged from those of its parental species and became quantitatively and qualitatively reduced, including the complete suppression of isoprene production.

  1. Rapid Synthesis of Gold Nanoparticles from Quercus incana and Their Antimicrobial Potential against Human Pathogens

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    Rizwana Sarwar

    2017-01-01

    Full Text Available In current study, bioreduction of tetrachloroauric acid (HAuCl4·3H2O was carried out using leaves extract of Quercus incana for nanoparticle synthesis. The nanoparticles were characterized by ultraviolet visible spectrum (UV, Fourier-transform infrared (FT-IR, and transmission electron microscopy (TEM analysis. The gold nanoparticles (GNPs were generally clumpy agglomerates of polydispersed particles, with an average size in the range 5.5–10 nm. The Gas chromatography–mass spectrometry (GC–MS qualitative analysis and FT-IR data supported the presence of bioactive compounds, which are responsible for the metal reduction and nanoparticles stabilization. The biocompatibility of synthesized GNPs was evaluated via antibacterial activity by using human bacterial pathogens. The results showed that synthesized GNPs showed enhanced antibacterial activity against all bacterial pathogens.

  2. TOLERANCIA AL FUEGO EN Quercus magnoliifolia1

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    Miguel Ángel López Moctezuma

    2015-06-01

    Full Text Available RESUMENCon el objetivo de conocer la respuesta de Quercus magnoliifolia al fuego en mortalidad y rebrotación, se aplicó una quema prescrita intensa, en fajas a favor de viento y pendiente, a una parcela de 0.5 ha en el estado de Guerrero, México, en abril de 2009. La quema inició a las 10:20 y duró 1 h 26 min. Se midieron las variables meteorológicas temperatura (25-28 °C, humedad relativa (33-24%, y velocidad del viento (7-25 km/h; y de comportamiento del fuego (largo de llama, de 0.5 a 3 m.Seis meses después se midieron variables de la estructura del arbolado y de severidad de la quema. El análisis de datos involucró regresión logarítmica y regresión logística. Los valores estructurales medios fueron: altura (11.2 m, diámetro normal (12. 2 cm y altura de copas (6.8 m. Se halló relación logarítmica directa entre el largo de llama y la velocidad del viento (R2=0.65. No hubo mortalidad producto de la quema, pero 33 % de los árboles rebrotaron. Las variables explicativas de la probabilidad de rebrotación fueron: altura (p=0.0159, diámetro normal (p=0.0394y altura a la base de copas (p=0.0487. La cicatriz sobre el tronco alcanzó 2.6 m y el chamuscado de copas 62 %, en promedio. La especie muestra resistencia a fuego poco severo, gracias a su corteza, y tolerancia a fuego más severo. Las quemas prescritas contribuirían a reducir impactos negativos de incendios en el arbolado.

  3. SORPTION PERFORMANCE OF QUERCUS CERRIS CORK WITH POLYCYCLIC AROMATIC HYDROCARBONS AND TOXICITY TESTING

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    M. Àngels Olivella

    2011-06-01

    Full Text Available Quercus cerris is an important oak species extended in large areas of Eastern Europe and Minor Asia that has a thick bark which is not utilized at all. The sorption performance of cork from Quercus cerris bark with four polycyclic aromatic hydrocarbons (PAHs (acenaphthene, fluorene, phenanthrene, and anthracene was investigated. Quercus cerris cork was characterized for elemental analysis, acidic groups, and summative chemical composition, and the results were compared with Quercus suber cork. A Microtox® test was carried out to test for the release of any toxic compounds into the solution. All isotherms fit the Freundlich model and displayed linear n values. Quercus cerris exhibited a high efficiency for sorption of PAHs for the studied concentrations (5 to 50 µg/L with 80-96% removal, while the desorption isotherms showed a very low release of the adsorbed PAHs (<2%. In relation to Quercus suber cork, KF values of Quercus cerris cork are about three times lower. The quantity of Quercus cerris cork required to reduce water pollution by PAHs was estimated to be less than twice the quantity of other adsorbents such as aspen wood and leonardite. Toxicity tests indicated that non-toxic compounds were released into the solution by the Quercus cerris and Quercus suber cork samples. Overall the results indicate the potential use of Quercus cerris cork and of Quercus suber cork as effective and economical biosorbents for the treatment of PAH-contaminated waters.

  4. Crescimento de mudas de angico-vermelho (Anadenanthera macrocarpa (Benth. Brenan sob diferentes doses de macronutrientes Growth of angico vermelho (Anadenanthera macrocarpa (Benth. Brenan seedlings under different macronutrient doses

    Directory of Open Access Journals (Sweden)

    Elzimar de Oliveira Gonçalves

    2008-12-01

    Full Text Available Neste trabalho, objetivou-se avaliar, por meio de características morfológicas, o efeito de doses de macronutrientes no crescimento e desenvolvimento de mudas de angico- vermelho (Anadenanthera macrocarpa (Benth. Brenan produzidas em amostras de três classes de solo (Argissolo Vermelho-Amarelo, Latossolo Vermelho-Amarelo álico e Latossolo Vermelho-Amarelo distrófico. As mudas foram plantadas em vasos com capacidade para 2,1 dm³. O experimento foi conduzido no período de dezembro de 2004 a maio de 2005. Os tratamentos foram delimitados segundo uma matriz baconiana, em que se variaram os macronutrientes em três doses diferentes, mais dois tratamentos adicionais (zero e base, com quatro repetições. As fontes de N, K e S foram parceladas em quatro vezes (0-30-60-90 dias. Em termos gerais, o maior crescimento das plantas ocorreu no Latossolo Vermelho-Amarelo álico. O nutriente que mais surtiu efeitos significativos foi o P, sendo recomendadas doses de 150 a 250 mg dm-3. Para a aplicação de N, recomendam-se doses mínimas de 50 mg/dm³. A aplicação de S deve ser de 20 a 80 mg dm-3. As respostas à aplicação dos demais nutrientes (Ca, Mg e K, em muitos casos, não ocorreu, evidenciando-se que a espécie tem baixo requerimento por eles. Entretanto, partindo desse estudo, sugerem-se novos estudos com os nutrientes K e Ca, para produção de mudas da referida espécie nesses solos.This work aimed to evaluate, by means of morphological characteristics, the effect of macronutrient doses on the growth of angico vermelho (Anadenanthera macrocarpa (Benth. Brenan seedlings cultivated in three soils (Red Yellow Argisol, Red Yellow Dystrophic Latosol and Red Yellow alic Latosol. The seedling were sown in vases with capacity of 2.1 dm³ . The experiment was carried out from December 2004 to June 2005. The treatments were delimited according to a Baconian matrix, with macronutrients varying in three different doses, plus two additional treatments

  5. Interacciones farmacológicas de las hojas de Maytenus macrocarpa o “chuchuhuasi” con fármacos inhibitorios y estimuladores de la motilidad intestinal

    OpenAIRE

    Meléndez-Espíritu, S.; Huaccho Rojas, Juan Jesús; Santos-Cajahuanca, F.; Abanto-Cabeza, C.; Jáuregui-Farfán, J.; Mendoza-Toribio, J.; Morales-Zenteno, E.; Salgado-Silva, L.; Sueyoshi-Hernández, H.; Robles-Ojeda, M.; Loja Herrera, Berta; Alvarado Yarasca, Ángel Tito; Salazar Granara, Alberto Alcibíades

    2013-01-01

    OBJETIVO: Determinar las posibles interacciones farmacológicas de las hojas de Maytenus macrocarpa, con fármacos estimulantes e inhibitorios de la motilidad intestinal. MÉTODOS: Se utilizaron 110 ratones albinos machos, con pesos medios de 25 g, se empleó el método de Arbos y col, se administró carbón activado al 5 % vía oral, dosis de 0.1ml/10g, como marcador intestinal. Los grupos experimentales fueron: control (agua destilada 0,3ml), hojas de chuchuhuasi 1 (500mg/kg), hojas de chuchuhua...

  6. Bioclimatic characteristic of oak species Quercus macranthera subsp. syspirensis and Quercus petraea subsp. pinnatiloba in Turkey.

    Science.gov (United States)

    Kargioglu, Mustafa; Serteser, Ahmet; Senkul, Cetin; Konuk, Muhsin

    2011-01-01

    This study was carried out to determine some bioclimatic characteristics such as humidity category (Q2), winter variant (m), the length of the dry season (LDS) and the dry season water deficit (DSWD) of naturally growing two endemic oak taxa, Quercus macranthera subsp. syspirensis and Q. petraea subsp. pinnatiloba, living in Turkey. Our findings showed that bioclimatic tolerance range of Q. macranthera subsp. syspirensis possess 7 different types of Mediterranean bioclimate while Q. petraea subsp. pinnatiloba had 8 of them. Although Q. macranthera subsp. syspirensis was ranging among the semiarid, freezing and very cold, Q. petraea subsp. pinnatiloba was among sub-humid, freezing and very cold ambient. It was briefly established that Q. macranthera subsp. syspirensis prefers semi-arid and very cold/freezing conditions and Q. petraea subsp. pinnatiloba prefers sub-humid and cold/very cold climatic conditions.

  7. Cryopreservation of Quercus suber and Quercus ilex embryonic axes: in vitro culture, desiccation and cooling factors.

    Science.gov (United States)

    Gonzalez-Benito, M Elena; Prieto, Roberto-Moreno; Herradon, Esther; Martin, Carmen

    2002-01-01

    This study examines different factors included in the cryopreservation protocols for Quercus ilex and Q. suber embryonic axes. In vitro incubation temperature played an important role in the appropriate development of Q. ilex axes, as 15 degrees C was superior to 25 degrees C. Q. suber axes proved to be more sensitive to desiccation and cooling. Poor survival (35%) was observed when axes were included into cryovials and then in liquid nitrogen, and none when immersed in sub-cooled liquid nitrogen (-210 degrees C). Q. ilex axes showed poorly organised development in vitro (c. 50% of non-cooled axes showed shoot development). However, c. 80% survival was observed after cryopreservation (either in liquid nitrogen or sub-cooled liquid nitrogen at 0.34 g water / g dry weight), of which c. 15% showed shoot development.

  8. Distinction between injury to tree leaves by ozone and mesophyll-feeding leafhoppers

    Energy Technology Data Exchange (ETDEWEB)

    Hibben, C.R.

    1969-06-01

    The phytotoxic effects of ozone and mesophyll-feeding leafhoppers were contrasted microscopically and histologically on leaves of Acer saccharum Marsh., Quercus rubra L., and Cornus florida L. Injuries induced by the two agents were readily distinguished by the differences in location, configuration, color, and size of the external symptoms, and by the characteristics of affected palisade parenchyma cells.

  9. Reviewing morphologic specifications of acorn leaves and fruits in lorestan province

    Directory of Open Access Journals (Sweden)

    Naser Nazar

    2015-06-01

    Full Text Available Zagros forests, as the greatest jungle area of the country, are considered not only as a high-economic zone in wooden products, but also as a highly important zone in environmental values. It should be mentioned that acorn is one of the main elements in the forests of Lorestan, and grows on different ecologic conditions’ realizing the variance-range of quantities and qualities aspects of leaves and fruits. This research has been done within the seven zones of Lorestan province’s acorn forests. 40 samples of leaf and fruit have been gathered from various trees. For each sample, 8 morphological aspects of fruit, and 16 morphological aspect of leaf were measured and recorded. Received data were statistically analyzed by Minitab ver.14 software. Results show that there are three types of acorn in the province of Lorestan: Quercus Persica (Persian acorn, Quercus Branti (Broodar, and Quercus Infectoria (Darmazoo. The quercus infectoria can be seen separately on the zone of Zasht & Ghalai; two types of branti and persica can be seen irregularly. On Ghalai zone, due to the rain fall rate and more humidity in comparison to other zones, suitable conditions are available for the growth of Quercus infectoria. Among the reviewed aspects in this research, leaf color, the existence of fluff on leaves, existence of teeth, and the length of grain cover have the greatest effect on the separation of Persia and branti from infectoria.

  10. Limitations due to water stress on leaf net photosynthesis of Quercus coccifera in the Portuguese evergreen scrub

    Energy Technology Data Exchange (ETDEWEB)

    Tenhunen, J.D.; Lange, O.L.; Harley, P.C.; Beyschlag, W.; Meyer, A.

    1985-01-01

    Gas exchange characteristics in leaves of the sclerophyll shrub Quercus coccifera were studied in the natural habitat in Portugal during spring and during the summer dry period. Compared to other sclerophyll species growing at the same site, photosynthesis in leaves of Quercus coccifera was less affected by water stress. Moderate water stress after six weeks of drought led to large decreases in stomatal conductance but no change in mesophyll photosynthetic capacity as compared to late spring. Leaf internal CO/sub 2/ pressure remained near 220 ..mu..bar during diurnal courses in the spring. On midsummer days, leaf internal CO/sub 2/ decreased from a late morning value of 200 ..mu..bar to a late afternoon value of approximately 150 ..mu..bar. In contrast to Quercus suber, restriction of CO/sub 2/ supply due to stomatal closure reduced net CO/sub 2/ uptake at midday and in the afternoon during midsummer. A decrease in leaf carboxylation efficiency and an increase in CO/sub 2/ compensation point at midday also played an important role in determining the diurnal course of net photosynthesis. During the late stages of drought in September, severe water stress led to reduction in mesophyll photosynthetic capacity and further reduction in leaf conductance. The observed decrease in mesophyll photosynthetic capacity was correlated with decrease in the daily minimum leaf water potential to greater negative values than -30 bar. At this time, CO/sub 2/ saturated photosynthetic rates decreased as much as 50% over the course of a day when measured at constant saturating light, 32/sup 0/C leaf temperature, and a water vapor mole fraction difference between leaf and air of 30 mbar bar/sup -1/. 24 references, 9 figures.

  11. Hydrogen peroxide concentrations in leaves under natural conditions.

    Science.gov (United States)

    Cheeseman, John M

    2006-01-01

    While H2O2 has been implicated in numerous plant environmental responses, normal levels and variabilities are poorly established, and estimates of leaf tissue concentrations span more than three orders of magnitude, even in a single species under similar conditions. Here, leaf tissue H2O2 contents under natural conditions are reported after determining (i) that H2O2 in extracts was stable with time, (ii) that H2O2 added to the extract was recovered quantitatively, and (iii) that the H2O2 calibration curve was unaffected (or quantifiably affected) by the extract. The broad applicability of the protocol and variability in leaf concentrations were demonstrated using tissue collected from several habitats in association with three, more extensive, experiments. The first involved nychthemeral studies of the mangrove, Rhizophora mangle L. Lowest H2O2 levels occurred in the early morning and near sunset, with higher levels both at midday and at night. Second, using five temperate species in Spring, concentrations were compared on a warm, sunny day and a cool, cloudy day. Higher concentrations were found on the warm day for Aesculus glabra Willd., Glechoma hederacea L., Plantago major L., and Viola soraria Willd., while there were no differences in Quercus macrocarpa Michx. Finally, the effects of elevated CO2 and ozone were examined in soybean, Glycine max L. Pioneer 93B15 under Free Air gas Concentration Enrichment (FACE) conditions. Both supplements led to elevated H2O2. Overall, mean leaf, midday, and mid-summer H2O2 concentrations ranged from 0.67 micromol (gFW)(-1) in mangrove to 3.6 micromol (gFW)(-1) in A. glabra Willd. Greatest within-species differences were only 2.5-fold in any of the studies.

  12. Protective role of Cupressuflavone from Cupressus macrocarpa against carbon tetrachloride-induced hepato- and nephrotoxicity in mice.

    Science.gov (United States)

    Al-Sayed, Eman; Abdel-Daim, Mohamed M

    2014-12-01

    The hepatoprotective and nephroprotective activity of cupressuflavone isolated from Cupressus macrocarpa was investigated against CCl4-induced toxicity in mice. Cupressuflavone was administered (40, 80, and 160 mg/kg/day) for five days. CCl4 was administered (0.5 mL/kg intraperitoneally) at the end of the experiment. A substantial increase (p < 0.001) in the levels of alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, lactate dehydrogenase, total bilirubin, cholesterol, creatinine, uric acid, urea, and malondialdehyde was observed in the CCl4-treated group compared to the normal control group. In contrast, a significant reduction (p < 0.001) in glutathione and superoxide dismutase contents as well as the total protein level was evident in the CCl4-intoxicated mice. Cupressuflavone pretreatment markedly inhibited the CCl4-induced increase in alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, lactate dehydrogenase, cholesterol, creatinine, uric acid, urea, and malondialdehyde levels in a dose-dependent manner (p < 0.001 at all the tested doses). In addition, a significant (p < 0.001) and dose-dependent decrease in the total bilirubin levels was evident by cupressuflavone pretreatment (80 and 160 mg/kg/day) when compared to the CCl4-intoxicated group. Furthermore, cupressuflavone administration significantly increased the activity of antioxidant parameters glutathione and superoxide dismutase as well as the serum protein levels (p < 0.001 at all the tested doses) in a dose-dependent manner. Histological observations confirmed the strong hepato- and nephroprotective activity. These findings suggest that cupressuflavone could exert a beneficial effect against oxidative stress by enhancing the antioxidant defense status, reducing lipid peroxidation, and protecting against the pathological changes induced by CCl4 in the liver and kidney tissues. The structure of cupressuflavone was identified by

  13. A discrimination between Quercus robur L. and Q. petraea

    NARCIS (Netherlands)

    Bakker, E.G.; Dam, van B.C.; Eck, van H.J.; Jacobsen, E.

    2001-01-01

    In natural populations, Quercus robur L. and Q. petraea (Matt.) Liebl. comprise a morphological continuum due to hybridization and/or an overlap in variation between the two species. In order to obtain diagnostic markers to investigate these morphological intermediate forms, leaf morphology and AFLP

  14. In vitro propagation of northern red oak (Quercus rubra L.)

    Science.gov (United States)

    G. Vengadesan; Paula M. Pijut

    2009-01-01

    In vitro propagation of northern red oak (Quercus rubra) shoots was successful from cotyledonary node explants excised from 8-wk-old in vitro grown seedlings. Initially, four shoots per explant were obtained on Murashige and Skoog (MS) medium supplemented with 4.4 µM 6-benzylaminopurine (BA), 0.45 ...

  15. Ellagitannins and complex tannins from Quercus petraea bark.

    Science.gov (United States)

    König, M; Scholz, E; Hartmann, R; Lehmann, W; Rimpler, H

    1994-10-01

    The ellagitannins 2,3-(S)-hexahydroxydiphenoyl-glucose, pedunculagin, vescalagin, and castalagin; the flavanoellagitannins acutissimin A, acutissimin B, eugenigrandin A, guajavin B, and stenophyllanin C; and the procyanidinoellagitannin mongolicanin have been isolated from the bark of Quercus petraea. The ellagitannin fraction had a weak antisecretory effect.

  16. Interspecific variation in functional traits of oak seedlings (Quercus ilex, Quercus trojana, Quercus virgiliana) grown under artificial drought and fire conditions.

    Science.gov (United States)

    Chiatante, D; Tognetti, R; Scippa, G S; Congiu, T; Baesso, B; Terzaghi, M; Montagnoli, A

    2015-07-01

    To face summer drought and wildfire in Mediterranean-type ecosystems, plants adopt different strategies that involve considerable rearrangements of biomass allocation and physiological activity. This paper analyses morphological and physiological traits in seedlings of three oak species (Quercus ilex, Quercus trojana and Quercus virgiliana) co-occurring under natural conditions. The aim of this study was to evaluate species-specific characteristics and the response of these oak seedlings to drought stress and fire treatment. Seedlings were kept in a growth chamber that mimicked natural environmental conditions. All three species showed a good degree of tolerance to drought and fire treatments. Differences in specific biomass allocation patterns and physiological traits resulted in phenotypic differences between species. In Q. ilex, drought tolerance depended upon adjustment of the allocation pattern. Q. trojana seedlings undergoing mild to severe drought presented a higher photosystem II (PSII) efficiency than control seedlings. Moreover, Q. trojana showed a very large root system, which corresponded to higher soil area exploitation, and bigger leaf midrib vascular bundles than the other two species. Morphological and physiological performances indicated Q. trojana as the most tolerant to drought and fire. These characteristics contribute to a high recruitment potential of Q. trojana seedlings, which might be the reason for the dominance of this species under natural conditions. Drought increase as a result of climate change is expected to favour Q. trojana, leading to an increase in its spatial distribution.

  17. In situ morphological assessment of apoptosis induced by Phaleria macrocarpa (Boerl.) fruit ethyl acetate fraction (PMEAF) in MDA-MB-231 cells by microscopy observation.

    Science.gov (United States)

    Kavitha, Nowroji; Chen, Yeng; Kanwar, Jagat R; Sasidharan, Sreenivasan

    2017-03-01

    Phaleria macrocarpa (Boerl.) is a well-known medicinal plant and have been extensively used as traditional medicine for ages in treatment of various diseases. The purpose of this study was to determine the in situ cytotoxicity effect P. macrocarpa fruit ethyl acetate fraction (PMEAF) by using various conventional and modern microscopy techniques. The cytotoxicity of PMEAF treated MDA-MB-231 cells was determined through the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cytotoxicity assay and CyQuant Cell Proliferation Assay after 24h of treatment. Both results were indicated that the PMEAF is a potential anticancer agent with the average IC50 values of 18.10μg/mL by inhibiting the MDA-MB-231 cell proliferation. Various conventional and modern microscopy techniques such as light microscopy, holographic microscopy, transmission (TEM) and scanning (SEM) electron microscope were used for the observation of morphological changes in PMEAF treated MDA-MB-231cells for 24h. The characteristic of apoptotic cell death includes cell shrinkage, membrane blebs, chromatin condensation and the formation of apoptotic bodies were observed. PMEAF might be the best candidate for developing more potent anticancer drugs or chemo-preventive supplements.

  18. Leaving Libya

    Energy Technology Data Exchange (ETDEWEB)

    Mc Kenzie-Brown, Peter

    2011-07-15

    Canadian workers in Libya have been leaving the country due to civic unrest. Canadian companies evacuated their expat employees in cooperation with the Canadian government, without regard to the financial aspect, to keep them safe. Canadian expats are optimistic about the future.

  19. Leaving Iraq?

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    It has been three years since the war in Iraq began, but the situation in the country, especially the security, has not improved much. Meanwhile, the world is wondering when U.S. troops will leave, and the American public appears to be getting impatient with the seemingly endless casualty reports. Some groups have held

  20. PAHs in decaying Quercus ilex leaf litter: mutual effects on litter decomposition and PAH dynamics.

    Science.gov (United States)

    De Nicola, F; Baldantoni, D; Alfani, A

    2014-11-01

    The investigation of the relationships between litter decomposition and polycyclic aromatic hydrocarbons (PAHs) is important to shed light not only on the effects of these pollutants on fundamental ecosystem processes, such as litter decomposition, but also on the degradation of these pollutants by soil microbial community. This allows to understand the effect of atmospheric PAH contamination on soil PAH content via litterfall. At this aim, we studied mass and PAH dynamics of Quercus ilex leaf litters collected from urban, industrial and remote sites, incubated in mesocosms under controlled conditions for 361d. The results highlighted a litter decomposition rate of leaves sampled in urban>industrial>remote sites; the faster decomposition of litter of the urban site is also related to the low C/N ratio of the leaves. The PAHs showed concentrations at the beginning of the incubation of 887, 650 and 143 ng g(-1)d.w., respectively in leaf litters from urban, industrial and remote sites. The PAHs in litter decreased along the time, with the same trend observed for mass litter, showing the highest decrease at 361 d for the urban leaf litter. Anyway, PAH dynamics in all the litters exhibited two phases of loss, separated by a PAH increase observed at 246 d and mainly linked to benzo[e]pyrene.

  1. A comparative analysis of stomata and leaf trichome characteristics in Quercus robur L. genotypes

    Directory of Open Access Journals (Sweden)

    Nikolić Nataša P.

    2003-01-01

    Full Text Available The objective of this study was to determine genotype variability of leaf trichome and stoma characteristics. Leaves were sampled from seventeen pedunculate oak (Quercus robur L genotypes originating from clonal seed orchard Banov Brod (Srem, the Vojvodina Province. The pedunculate oak has hypostomatal leaves. Statistically significant differences were found for the dimensions and density of stomata. Genotype variability of stomatal dimensions was less pronounced in comparison with their density (CV = 8.88%. Stomata number ranged from 530 to 791 per mm2 of leaf area; genotypes 18 and 25 could be distinguished from the others for the highest stomata number per leaf unit area, genotype 35 for the lowest number. In all genotypes, only solitary eglandular trichomes were observed on the adaxial leaf surface while both solitary eglandular and uniseriate glandular hairs were present on the abaxial surface. Single glandular trichomes were observed in all genotypes, while some of them were characterized by the presence of two (genotypes 4, 5, 6, 16, 22, 25, 28, 29, 30, 35, 38, 40, and 85 or three (genotypes 16, 25, 35 hairs joined by their basal cells.

  2. Assessment of ploidy stability of the somatic embryogenesis process in Quercus suber L. using flow cytometry.

    Science.gov (United States)

    Loureiro, J; Pinto, G; Lopes, T; Dolezel, J; Santos, C

    2005-08-01

    Flow cytometry analyses were used to verify the ploidy stability of Quercus suber L. somatic embryogenesis process. Leaf explants of two adult cork oak trees (QsG0 and QsG5) of the North of Portugal were inoculated on MS medium with 2,4-D and zeatin. After 3 months, calluses with embryogenic structures were isolated and transferred to fresh MS medium without growth regulators and somatic embryo evolution was followed. Morphologically normal somatic embryos (with two cotyledons) and abnormal somatic embryos (with one or three cotyledons) were used in this assay. Flow cytometry combined with propidium iodide staining was employed to estimate DNA ploidy levels and nuclear DNA content of somatic embryos and leaves from mother plants. No significant differences (P< or =0.05) were detected among embryos, and between the embryos and the mother plants. Also, after conversion of these embryos, no significant morphological differences were observed among the somatic embryo-derived plants. These results and further studies using converted plantlet leaves and embryogenic callus tissue indicate that embryo cultures and converted plantlets were stable with regard to ploidy level. As no major somaclonal variation was detected our primary goal of "true-to-type" propagation of cork oak using somatic embryogenesis was assured at this level. The estimation of the 2C nuclear DNA content for this species is similar to the previously obtained value.

  3. Airborne Quercus pollen in SW Spain: Identifying favourable conditions for atmospheric transport and potential source areas.

    Science.gov (United States)

    Maya-Manzano, José María; Fernández-Rodríguez, Santiago; Smith, Matt; Tormo-Molina, Rafael; Reynolds, Andrew M; Silva-Palacios, Inmaculada; Gonzalo-Garijo, Ángela; Sadyś, Magdalena

    2016-11-15

    The pollen grains of Quercus spp. (oak trees) are allergenic. This study investigates airborne Quercus pollen in SW Spain with the aim identifying favourable conditions for atmospheric transport and potential sources areas. Two types of Quercus distribution maps were produced. Airborne Quercus pollen concentrations were measured at three sites located in the Extremadura region (SW Spain) for 3 consecutive years. The seasonal occurrence of Quercus pollen in the air was investigated, as well as days with pollen concentrations ≥80Pm(-3). The distance that Quercus pollen can be transported in appreciable numbers was calculated using clusters of back trajectories representing the air mass movement above the source areas (oak woodlands), and by using a state-of-the-art dispersion model. The two main potential sources of Quercus airborne pollen captured in SW Spain are Q. ilex subsp. ballota and Q. suber. The minimum distances between aerobiological stations and Quercus woodlands have been estimated as: 40km (Plasencia), 66km (Don Benito), 62km (Zafra) from the context of this study. Daily mean Quercus pollen concentration can exceed 1,700Pm(-3), levels reached not less than 24 days in a single year. High Quercus pollen concentration were mostly associated with moderate wind speed events (6-10ms(-1)), whereas that a high wind speed (16-20ms(-1)) seems to be associated with low concentrations.

  4. Effect of high-pressure homogenization on the physical and antioxidant properties of Quercus resinosa infusions encapsulated by spray-drying.

    Science.gov (United States)

    Rocha-Guzmán, Nuria Elizabeth; Gallegos-Infante, José Alberto; González-Laredo, Rubén Francisco; Harte, Federico; Medina-Torres, Luis; Ochoa-Martínez, Luz Araceli; Soto-García, Marcela

    2010-06-01

    Quercus resinosa leaves are used in northern Mexico as a refreshing beverage rich in polyphenolic compounds. These leaves show astringency and hence need taste masking for incorporating in a food product. They also interact with many other food components and are not very stable to food processing environments, thus it is important to protect them and a common way is by encapsulation. In the present study the use of encapsulation by spray-drying of Quercus resinosa leaves infusions was evaluated. Q. resinosa leaves were collected, air dried, and milled prior to infusion preparation. Lactose-sodium caseinate blends at 3 different proportions (11 : 4%, 9 : 6%, and 7 : 8%) were dispersed with a constant amount of lyophilized infusion (0.075%) and processed under high-pressure homogenization (0, 100, 200, 300 MPa). Total phenolic content, DPPH kinetic analysis, deoxy-D-ribose oxidation inhibition, rheological evaluation, and particle size analysis were performed to evaluate the obtained capsules. High antioxidant activity was shown by capsules despite their very low concentration when inhibiting deoxy-D-ribose oxidation. Chain breaking rate was related to polyphenolic concentration in capsules. Using lactose-caseinate blends produces capsules of submicron to nanometer size that retain the good antioxidant capacities of original infusions.

  5. Effects of desiccation on temperate recalcitrant seeds: differential scanning calorimetry, gas chromatography, electron microscopy, and moisture studies on Quercus nigra and Quercus alba

    Science.gov (United States)

    K.F. Connor; F.T. Bonner; J.A Vozzo

    1996-01-01

    Investigations into the nature of desiccation-sensitive, or recalcitrant, seed behavior have as yet failed to identify exact causes of this phenomenon. Experiments with Quercus nigra L. and Quercus alba L. were conducted to examine physiological and biochemical changes brought about by seed desiccation and to determine if there...

  6. KAJIAN TERHADAP PROSPEK PENGEMBANGAN BAHAN BIOAKTIF BUAH MAHKOTA DEWA (P. Macrocarpa SEBAGAI KANDIDAT NEW CHEMICAL ENTITY (NCE UNTUK PENGOBATAN KANKER (SITOSTATIKA

    Directory of Open Access Journals (Sweden)

    Vivi Lisdawati

    2012-11-01

    Full Text Available Abstract. In the last few years there are tendency for cancer study to develop in discovery of new chemical entity (NCE for new drugs. The needed of NCE based on reality that cancer therapy reaches a resistant level very fast. By developing NCE, multiply cancer drugs can be used at one therapy and be implemented as a solution to inhibit a resistant level and very useful in recovery time. Natural products are the most important sources of NCE and could be used from plants, animals or minerals. Most of the natural products used in Indonesia are recognized from plants. Plants secondary metabolites show promise for cancer chemoprevention, which has been defined as the use of non cytotoxic nutrient or pharmacological agents to enhance intrinsic physiological mechanism that protect the organism against mutant clones of malignant cells. The study of plants secondary metabolites is nowadays moved from improvement of the empiric activity to meet the relationship between the structures of chemical compounds to its pharmacology activities. Development of study on plants in Indonesia is also pointed on discovery of NCE for new drugs of cancer and the cellular cytotoxic mechanism of the biological activity. Extracts from the fruit of P. macrocarpa is one of the sources for NCE of cancer drug in Indonesia. Some isolates already isolated from the extracts, i.e. lignan compound Ci9H2o06: 5-[4(4-Methoxy-phenyl-tetrahydrofurof3,4-cJfuran-l-yl]-benzene-1,2,3-triol and benzophenon compound: 4', 6-dihiroksi-4-metoksibenzofenon-2-0-glukoside. Using chemotaxonomy Dahlgren and Conqruist system approached indicate that these compounds have anti proliferation and pro apoptotic as their cytotoxic activities. The pharmacology activities from the fruit extracts also have been studied. For cytotoxic activities, the fruit extracts showed ICSo values from 5 to 7.71. jug/ml for leukemia LI 210 cell line; and IC50 values 196.74 jug/ml for HeLa cell line. The extracts also showed

  7. SSR markers for Quercus suber tree identification and embryo analysis.

    Science.gov (United States)

    Gómez, A; Pintos, B; Aguiriano, E; Manzanera, J A; Bueno, M A

    2001-01-01

    Three Quercus simple sequence repeat (SSR) markers were amplified by polymerase chain reaction (PCR) from nuclear DNA extracts of trees and in vitro-induced haploid embryos from anther cultures of Quercus suber L. These markers were sufficiently polymorphic to identify 10 of 12 trees located in two Spanish natural areas. The same loci have been analyzed in anther-derived haploid embryos showing the parental tree allele segregation. All the alleles were present in the haploid progeny. The presence of diverse alleles in embryos derived from the same anther demonstrated that they were induced on multiple microspores or pollen grains and they were not clonally propagated. Also, diploid cultures and mixtures of haploid-diploid tissues were obtained. The origin of such cultures, either somatic or gametic, was elucidated by SSR markers. All the embryos showed only one allele, corroborating a haploid origin. Allelic composition of the haploid progeny permitted parental identification among all analyzed trees.

  8. Cork oak (Quercus suber L.) seedlings acclimate to elevated

    OpenAIRE

    2012-01-01

    Leaf gas-exchange, leaf and shoot anatomy, wood density and hydraulic conductivity were investigated in seedlings of Quercus suber L. grown for 15 months either at elevated (700 lmol mol-1) or normal (350 lmol mol-1) ambient atmospheric CO2 concentrations. Plants were grown in greenhouses in a controlled environment: relative humidity 50% (±5), temperature similar to external temperature and natural light conditions. Plants were supplied with nutrients and two water re...

  9. Dynamics of Long-lived Foundation Species: The History of Quercus in Southern Scandinavia

    OpenAIRE

    Foster, David Russell; Lindbladh, Matts

    2010-01-01

    (1) The long-term history of Quercus in southern Scandinavia has received little attention despite its important role in modern conservation. In this study the 4000-year dynamics of Quercus, its habitat and other important taxa were analysed with pollen data from 25 small hollows and 6 regional sites across southern Scandinavia. The aim was to provide a context for understanding the species’ current status and managing its future dynamics. (2) The results indicate that Quercus is much less ab...

  10. 科尔沁沙地蒙古黄榆种群结构与空间分布格局%Population Structure and Spatial Pattern of Ulmus macrocarpa var.mongolica in Horqin Sandy Land,China

    Institute of Scientific and Technical Information of China (English)

    张雷; 王晓江; 胡尔查; 高桂英; 庞鑫; 于有忠; 张振华

    2011-01-01

    Based on an investigation into the Ulmus macrocarpa var. mongolica sparse forest in the Horqin Sandy Land, its population characteristics and spatial distribution were analyzed from aspects of static life table, mortality curve, age structure diagram and point pattern analysis diagram. The results showed: (1) The woody layer of the Ulmus macrocarpa sparse forest develops incompletely with single species, and the shrub layer appears sparsely, too. (2) The age structure of the Ulmus macrocarpa population is seriously defective with few saplings and even no saplings under 10 ages, and there is insufficient natural regeneration for the population. This community is in a serious degradation state. (3) The static life table indicates that the mortality of the Ulmus macrocarpa population is the highest during 40 to 50 years old and the lowest during the sapling stage. The survival curve of the Ulmus macrocarpa population tends to be the Deevey-Ⅰ type. (4) The spatial pattern of the population obeys a random distribution.%对科尔沁沙地分布的蒙古黄榆(Ulmus macrocarpa var.mongolica)疏林进行了调查研究,分析了其群落特征、种群结构和卒间分布规律;编制了种群的静态生命表;绘制了年龄结构图、存活曲线和点格局分析图.结果表明:①蒙古黄榆疏林木本层的发育并不完善,种类单一,偶尔出现灌木层;②蒙古黄榆种群的年龄结构极不合理,呈明显的衰退型.并且幼树较少,更不存在0~10 a的幼树.天然更新严重不足,群落正处于严重的退化状态;③蒙古黄榆的种群静态生命表表明,死亡率最高出现在40~50年龄段,幼年个体的死亡率最低,它的存活曲线趋向于Deevey Ⅰ型;④蒙古黄榆种群空间分布格局呈随机分布.

  11. Paisang ( Quercus griffithii): A Keystone Tree Species in Sustainable Agroecosystem Management and Livelihoods in Arunachal Pradesh, India

    Science.gov (United States)

    Singh, Ranjay K.; Singh, Anshuman; Garnett, Stephen T.; Zander, Kerstin K.; Lobsang; Tsering, Darge

    2015-01-01

    In a study of the traditional livelihoods of 12 Monpa and Brokpa villages in Arunachal Pradesh, India using social-ecological and participatory rural appraisal techniques, we found that the forest tree species paisang ( Quercus griffithii, a species of oak) is vital to agroecosystem sustainability. Paisang trees are conserved both by individuals and through community governance, because their leaves play a crucial role in sustaining 11 traditional cropping systems of the Monpa peoples. An Indigenous institution, Chhopa, regulates access to paisang leaves, ensuring that the relationship between paisang and traditional field crop species within Monpa agroecosystems is sustainable. The Monpa farmers also exchange leaves and agricultural products for yak-based foods produced by the transhumant Brokpa, who are primarily yak herders. Yak herds also graze in paisang groves during winter. These practices have enabled the conservation of about 33 landraces, yak breeds, and a number of wild plants. Paisang thus emerged as a culturally important keystone species in the cultures and livelihoods of both Monpa and Brokpa. Ecological and conservation knowledge and ethics about paisang vary with gender, social systems, and altitudes. Labor shortages, however, have already caused some changes to the ways in which paisang leaves are used and yak grazing patterns are also changing in the face of changes in attitude among local landowners. Given new competing interests, incentives schemes are now needed to conserve the ecologically sustainable traditional livelihoods.

  12. Spatial genetic structure in Beta vulgaris subsp. maritima and Beta macrocarpa reveals the effect of contrasting mating system, influence of marine currents, and footprints of postglacial recolonization routes.

    Science.gov (United States)

    Leys, Marie; Petit, Eric J; El-Bahloul, Yasmina; Liso, Camille; Fournet, Sylvain; Arnaud, Jean-François

    2014-05-01

    Understanding the factors that contribute to population genetic divergence across a species' range is a long-standing goal in evolutionary biology and ecological genetics. We examined the relative importance of historical and ecological features in shaping the present-day spatial patterns of genetic structure in two related plant species, Beta vulgaris subsp. maritima and Beta macrocarpa. Using nuclear and mitochondrial markers, we surveyed 93 populations from Brittany (France) to Morocco - the southern limit of their species' range distribution. Whereas B. macrocarpa showed a genotypic structure and a high level of genetic differentiation indicative of selfing, the population genetic structure of B. vulgaris subsp. maritima was consistent with an outcrossing mating system. We further showed (1) a strong geographic clustering in coastal B. vulgaris subsp. maritima populations that highlighted the influence of marine currents in shaping different lineages and (2) a peculiar genetic structure of inland B. vulgaris subsp. maritima populations that could indicate the admixture of distinct evolutionary lineages and recent expansions associated with anthropogenic disturbances. Spatial patterns of nuclear diversity and differentiation also supported a stepwise recolonization of Europe from Atlantic-Mediterranean refugia after the last glacial period, with leading-edge expansions. However, cytoplasmic diversity was not impacted by postglacial recolonization: stochastic long-distance seed dispersal mediated by major oceanic currents may mitigate the common patterns of reduced cytoplasmic diversity observed for edge populations. Overall, the patterns we documented here challenge the general view of reduced genetic diversity at the edge of a species' range distribution and provide clues for understanding how life-history and major geographic features interact to shape the distribution of genetic diversity.

  13. [Effects of simulating acid rain on photosynthesis and chlorophyll fluorescence parameters of Quercus glauca Quercus glauca].

    Science.gov (United States)

    Wang, Sai; Yi, Li-Ta; Yu, Shu-Quan; Zhang, Chao; Shi, Jing-Jing

    2014-08-01

    At three levels of simulated acid rainfall intensities with pH values of 2.5 (severe), 40 (medium) and 5.6 (light) respectively, the responses of chlorophyll fluorescence and photosynthetic parameters of Quercus glauca seedlings were studied in three acid rainfall treatments, i. e. only the aboveground of seedlings exposed to acid rain (T1), both of the seedlings and soil exposed to acid rain (T2), only the soil exposed to acid rain (T3) compared with blank control (CK). Under the severe acid rainfall, T1 significantly inhibited chlorophyll synthesis, and thus reduced the primary photochemical efficiency of PS II ( F(v)/F(m)), potential activity of PS II (F(v)/F(o)) , apparent quantum (Y), net photosynthetic rate (P(n)), and transpiration rate (T(r)), but increased the light compensation point (LCP) and dark respiration rate (R(d)) of Q. glauca seedlings. T2 inhibited, but T3 played a little enhancement on the aforementioned parameters of Q. glauca seedlings. Under the conditions of medium and light acid rainfall intensities, the above parameters in the three treatments were higher than that of CK, except with lower R(d). The chlorophyll fluorescence and photosynthetic parameters showed a similar tendency in the three treatments, i. e. T2>T3 >T1. It indicated that T1 had the strongest inhibition on seedlings in condition of the severe acid rainfall, while T2 had the most dramatic facilitating effect on seedlings under the medium and light acid rainfall. Intensity of acid rainfall had significant influences on SPAD, F(v)/F(m), F(v)/F(o), Y, P(n), T(r), and maximum photosynthetic rate (A(max)), whereas treatments of acid rainfall affected SPAD, F(v)/F(m), Y, P(n), T(r), A(max) and light saturation point (LSP). The interaction of acid rainfall intensities and treatments played significant effects on SPAD, F(v)/F(m), Y, P(n) and A(max).

  14. Absence and leave; sick leave. Final rule.

    Science.gov (United States)

    2010-12-03

    The U.S. Office of Personnel Management is issuing final regulations on the use of sick leave and advanced sick leave for serious communicable diseases, including pandemic influenza when appropriate. We are also permitting employees to substitute up to 26 weeks of accrued or accumulated sick leave for unpaid Family and Medical Leave Act (FMLA) leave to care for a seriously injured or ill covered servicemember, as authorized under the National Defense Authorization Act for Fiscal Year 2008, including up to 30 days of advanced sick leave for this purpose. Finally, we are reorganizing the existing sick leave regulations to enhance reader understanding and administration of the program.

  15. The Quercus feeding Stigmella species of the West Palaearctic: new species, key and distribution (Lepidoptera: Nepticulidae)

    NARCIS (Netherlands)

    Nieukerken, van E.J.; Johansson, R.

    2003-01-01

    The species of the Stigmella ruficapitella group occurring in the Western Palaearctic and feeding on Quercus are reviewed. We recognise 19 species, five of which are described as new: Stigmella fasciata sp. n. on Quercus pubescens from Slovenia, Croatia, Greece and Turkey, S. cocciferae sp. n. on Q.

  16. Improved genetic transformation of cork oak (Quercus suber L.).

    Science.gov (United States)

    Alvarez-Fernández, Rubén; Ordás, Ricardo-Javier

    2012-01-01

    An Agrobacterium-mediated transformation system for selected mature Quercus suber L. trees has been established. Leaf-derived somatic embryos in an early stage of development are inoculated with an AGL1 strain harboring a kanamycin-selectable plasmid carrying the gene of interest. The transformed embryos are induced to germinate and the plantlets transferred to soil. This protocol, from adult cork oak to transformed plantlet, can be completed in about one and a half years. Transformation efficiencies (i.e., percentage of inoculated explants that yield independent transgenic embryogenic lines) vary depending on the cork oak genotype, reaching up to 43%.

  17. Photosynthesis and photosynthetic electron flow in the alpine evergreen species Quercus guyavifolia in winter

    Directory of Open Access Journals (Sweden)

    Wei Huang

    2016-10-01

    Full Text Available Alpine evergreen broadleaf tree species must regularly cope with low night temperatures in winter. However, the effects of low night temperatures on photosynthesis in alpine evergreen broadleaf tree species are unclear. We measured the diurnal photosynthetic parameters before and after cold snap for leaves of Quercus guyavifolia growing in its native habitat at 3290 m. On 11 and 12 December 2013 (before cold snap, stomatal and mesophyll conductances (gs and gm, CO2 assimilation rate (An, and total electron flow through PSII (JPSII at daytime were maintained at high levels. The major action of alternative electron flow was to provide extra ATP for primary metabolisms. On 20 December 2013 (after cold snap, the diurnal values of gs, gm, An and JPSII at daytime largely decreased, mainly due to the large decrease in night air temperature. Meanwhile, the ratio of photorespiration and alternative electron flow to JPSII largely increased on 20 December. Furthermore, the high levels of alternative electron flow were accompanied with low rates of extra ATP production. A quantitative limitation analysis reveals that the gm limitation increased on 20 December with decreased night air temperature. Therefore, the night air temperature was an important determinant of stomatal/mesophyll conductance and photosynthesis. When photosynthesis is inhibited following freezing night temperatures, photorespiration and alternative electron flow are important electron sinks, which support the role of photorespiration and alternative electron flow in photoportection for alpine plants under low temperatures.

  18. Photosynthesis and Photosynthetic Electron Flow in the Alpine Evergreen Species Quercus guyavifolia in Winter

    Science.gov (United States)

    Huang, Wei; Hu, Hong; Zhang, Shi-Bao

    2016-01-01

    Alpine evergreen broadleaf tree species must regularly cope with low night temperatures in winter. However, the effects of low night temperatures on photosynthesis in alpine evergreen broadleaf tree species are unclear. We measured the diurnal photosynthetic parameters before and after cold snap for leaves of Quercus guyavifolia growing in its native habitat at 3290 m. On 11 and 12 December 2013 (before cold snap), stomatal and mesophyll conductances (gs and gm), CO2 assimilation rate (An), and total electron flow through PSII (JPSII) at daytime were maintained at high levels. The major action of alternative electron flow was to provide extra ATP for primary metabolisms. On 20 December 2013 (after cold snap), the diurnal values of gs, gm, An, and JPSII at daytime largely decreased, mainly due to the large decrease in night air temperature. Meanwhile, the ratio of photorespiration and alternative electron flow to JPSII largely increased on 20 December. Furthermore, the high levels of alternative electron flow were accompanied with low rates of extra ATP production. A quantitative limitation analysis reveals that the gm limitation increased on 20 December with decreased night air temperature. Therefore, the night air temperature was an important determinant of stomatal/mesophyll conductance and photosynthesis. When photosynthesis is inhibited following freezing night temperatures, photorespiration and alternative electron flow are important electron sinks, which support the role of photorespiration and alternative electron flow in photoportection for alpine plants under low temperatures. PMID:27812359

  19. Diurnal and seasonal emissions of volatile organic compounds from cork oak ( Quercus suber) trees

    Science.gov (United States)

    Pio, C. A.; Silva, P. A.; Cerqueira, M. A.; Nunes, T. V.

    The emissions of volatile organic compounds from Quercus suber (cork oak) were investigated at two rural sites in Portugal using a branch enclosure method with subsequent analysis by gas chromatography/flame ionization detection. Q. suber leaves released important amounts of monoterpenes, mainly in the form of limonene, α-pinene, β-pinene and sabinene. However, significant temporal and intraspecific variations in the relative abundance of the dominant compounds were found during this survey. Emissions from Q. suber were strongly dependent on light and temperature, showing a similar behaviour to that of plant species known to be isoprene producers. But, this work also revealed that, although at lower rates, emissions of monoterpenes continued in the dark for several hours. Emission rates were quite well predicted by algorithms based on the Guenther and Tingey equations; correlations of measurements with modelled data were, on average, r2=0.80. A pronounced seasonal variation was recorded for the emissions of monoterpenes. During the 1-yr study period, standard emission rates ranged between a minimum of 0.2 μg g dw-1 h -1, in winter, and a maximum of 20-30 μg g dw-1 h -1, in summer.

  20. How drought severity constrains GPP and its partitioning among carbon pools in a Quercus ilex coppice?

    Directory of Open Access Journals (Sweden)

    S. Rambal

    2014-06-01

    Full Text Available The partitioning of photosynthates toward biomass compartments has a crucial role in the carbon sink function of forests. Few studies have examined how carbon is allocated toward plant compartments in drought prone forests. We analyzed the fate of GPP in relation to yearly water deficit in an old evergreen Mediterranean Quercus ilex coppice severely affected by water limitations. Gross and net carbon fluxes between the ecosystem and the atmosphere were measured with an eddy-covariance flux tower running continuously since 2001. Discrete measurements of litterfall, stem growth and fAPAR allowed us to derive annual productions of leaves, wood, flowers and acorns and an isometric relationship between stem and belowground biomass has been used to estimate perennial belowground growth. By combining eddy-covariance fluxes with annual productions we managed to close a C budget and derive values of autotrophic and heterotrophic respirations, NPP and carbon use efficiency (CUE, the ratio between NPP and GPP. Average values of yearly NEP, GPP and Reco were 282, 1259 and 977 g C m−2. The corresponding ANPP components were 142.5, 26.4 and 69.6 g C m−2 for leaves, reproductive effort (flowers and fruits and stems. Gross and net carbon exchange between the ecosystem and the atmosphere were affected by annual water deficit. Partitioning to the different plant compartments was also impacted by drought, with a hierarchy of responses going from the most affected, the stem growth, to the least affected, the leaf production. The average CUE was 0.40, which is well in the range for Mediterranean-type forest ecosystems. CUE tended to decrease more slightly in response to drought than GPP and NPP, probably due to drought-acclimation of autotrophic respiration. Overall, our results provide a baseline for modeling the inter-annual variations of carbon fluxes and allocation in this widespread Mediterranean ecosystem and highlight the value of maintaining continuous

  1. How drought severity constrains GPP and its partitioning among carbon pools in a Quercus ilex coppice?

    Science.gov (United States)

    Rambal, S.; Lempereur, M.; Limousin, J. M.; Martin-StPaul, N. K.; Ourcival, J. M.; Rodríguez-Calcerrada, J.

    2014-06-01

    The partitioning of photosynthates toward biomass compartments has a crucial role in the carbon sink function of forests. Few studies have examined how carbon is allocated toward plant compartments in drought prone forests. We analyzed the fate of GPP in relation to yearly water deficit in an old evergreen Mediterranean Quercus ilex coppice severely affected by water limitations. Gross and net carbon fluxes between the ecosystem and the atmosphere were measured with an eddy-covariance flux tower running continuously since 2001. Discrete measurements of litterfall, stem growth and fAPAR allowed us to derive annual productions of leaves, wood, flowers and acorns and an isometric relationship between stem and belowground biomass has been used to estimate perennial belowground growth. By combining eddy-covariance fluxes with annual productions we managed to close a C budget and derive values of autotrophic and heterotrophic respirations, NPP and carbon use efficiency (CUE, the ratio between NPP and GPP). Average values of yearly NEP, GPP and Reco were 282, 1259 and 977 g C m-2. The corresponding ANPP components were 142.5, 26.4 and 69.6 g C m-2 for leaves, reproductive effort (flowers and fruits) and stems. Gross and net carbon exchange between the ecosystem and the atmosphere were affected by annual water deficit. Partitioning to the different plant compartments was also impacted by drought, with a hierarchy of responses going from the most affected, the stem growth, to the least affected, the leaf production. The average CUE was 0.40, which is well in the range for Mediterranean-type forest ecosystems. CUE tended to decrease more slightly in response to drought than GPP and NPP, probably due to drought-acclimation of autotrophic respiration. Overall, our results provide a baseline for modeling the inter-annual variations of carbon fluxes and allocation in this widespread Mediterranean ecosystem and highlight the value of maintaining continuous experimental

  2. Effect of flooding on C metabolism of flood-tolerant (Quercus robur) and non-tolerant (Fagus sylvatica) tree species.

    Science.gov (United States)

    Ferner, Eleni; Rennenberg, Heinz; Kreuzwieser, Jürgen

    2012-02-01

    Flooding is assumed to cause an energy crisis in plants because-due to a lack of O(2)-mitochondrial respiration is replaced by alcoholic fermentation which yields considerably less energy equivalents. In the present study, the effect of flooding on the carbon metabolism of flooding-tolerant pedunculate oak (Quercus robur L.) and flooding-sensitive European beech (Fagus sylvatica L.) seedlings was characterized. Whereas soluble carbohydrate concentrations dropped in roots of F. sylvatica, they were constant in Q. robur during flooding. At the same time, root alcohol dehydrogenase activities were decreased in beech but not in oak, suggesting substrate limitation of alcoholic fermentation in beech roots. Surprisingly, leaf and phloem sap sugar concentrations increased in both species but to a much higher degree in beech. This finding suggests that the phloem unloading process in flooding-sensitive beech was strongly impaired. It is assumed that root-derived ethanol is transported to the leaves via the transpiration stream. This mechanism is considered an adaptation to flooding because it helps avoid the accumulation of toxic ethanol in the roots and supports the whole plant's carbon metabolism by channelling ethanol into the oxidative metabolism of the leaves. A labelling experiment demonstrated that in the leaves of flooded trees, ethanol metabolism does not differ between flooded beech and oak, indicating that processes in the roots are crucial for the trees' flooding tolerance.

  3. STANDARDIZATION AND CONTAMINATION STUDIES ON NUTGALLS OF QUERCUS INFECTORIA OLIVIER

    Directory of Open Access Journals (Sweden)

    Asif M

    2012-08-01

    Full Text Available Drug consists of nutgalls of Quercus infectoria (Family-Fagaceae, commonly known as “Mazuphal”. Standardization parameters like, physical constants, ash content, solvent residues, phytochemical screening, fluorescence and microscopical analysis were carried out for the quality, strength and purity of the drug. The present work is an also attempt to evaluate contamination parameters for safety of an herbal drug Quercus infectoria such as microbial contamination, aflatoxins, pesticide residues and heavy metals. Result revealed that the total ash content and acid insoluble siliceous matter were found 2.11% and 0.22% respectively in the drug. The extractive values were varies at different solvent at different condition. Loss on drying and pH at 25(ºC were 9.97 and 6.1 respectively. Study revealed that total bacterial count and total fungal count were found to be within the permissible limit. Heavy metal like cadmium and mercury were not detected in the drug but arsenic (0.31 mg/kg and lead (0.70 mg/kg were found under permissible limit. Pesticide residue such as o, p- DDD, p, p- DDD, o p- DDE, p, p- DDE, o, p- DDT, p, p- DDT, α- Endosulfan, β – Endosulfan, Parathion, α- HCH, β- HCH, γ- HCH, δ- HCH was absent in the nutgalls.

  4. Myxomycetes from the bark of the evergreen oak Quercus ilex

    Directory of Open Access Journals (Sweden)

    Wrigley de Basanta, Diana

    1998-06-01

    Full Text Available The results of 81 moist chamber cultures of bark from living Quercus ilex trees are reponed. A total of 37 taxa are cited, extending the number of species found on this substrate to 55. The presence of Licea deplanata on the Iberian Península is confirmed. Seven new records are included for the province of Madrid. Some data are contributed on species frequency and incubation times.Se presentan los resultados de 81 cultivos en cámara húmeda de corteza de Quercus ilex vivo. Se citan 37 táxones, que amplían a 55 el número de especies de mixomicetes encontrados sobre este sustrato. Se confirma la presencia en la Península Ibérica de Licea deplanata, y se incluyen siete nuevas citas para la provincia de Madrid. Se aportan datos sobre frecuencia de aparición y tiempos de incubación de algunas especies.

  5. Allozymes Genetic Diversity of Quercus mongolica Fisch in China

    Institute of Scientific and Technical Information of China (English)

    LI Wenying; GU Wanchun

    2006-01-01

    A gel electrophoresis method was used to study the genetic diversity of 8 Quercus mongolica populations throughout its range in China.Eleven of 21 loci from 13 enzymes assayed were polymorphic.Q.mongolica maintained low level of genetic variation compared with the average Quercus species.At the species level,: the mean number of alleles per locus (A) was 1.905, the percentage of polymorphic loci (P) was 52.38%, the observed heterozygosity (He) was 0.092 and the expected heterozygosity (He) was 0.099.At the population level, the estimates were A =1.421, P =28.976%, Ho= 0.088, He =0.085.Genetic differentiation (Gst was high among populations, it was 0.107.According to the UPGMA cluster analysis based on the genetic distance, 4 populations located in northeast and 2 populations in southwest of the geographical distribution are classified into 2 subgroups, but there was no clear relationship between genetic distance and geographic distance among populations.The low level of genetic diversity of Q.mongolica might be related to the long-term exploitation as economic tree species in history are comparatively seriously disturbed and damaged by human beings, and most of the existing stands are secondary forests.

  6. A Study of Vegetation Development in Relation to Age of River Stabilization Structures Along a Channelized Segment of the Missouri River.

    Science.gov (United States)

    1975-01-25

    Featherly (1941) both concluded that riparian woodlands develop into Quercus macrocarpa (bur oak) - Quercus borealis (red oak) - Carya illinoensis (pecan...dominated communit4 es .. ........ .. 47 Quercus- Carya -dominated communities .. ........ .. 49 Diversity ......... ....................... .. 59 Similarity...Tilia-Quercus-dominated, and Quercus- Carya -dominated vegetation. The construction dates of the stabilization structures adjacent to the sites studied

  7. Soil properties and understory herbaceous biomass in forests of three species of Quercus in Northeast Portugal

    Directory of Open Access Journals (Sweden)

    Marina Castro

    2014-12-01

    Full Text Available Aim of study: This paper aims to characterize some soil properties within the first 25 cm of the soil profile and the herbaceous biomass in Quercus forests, and the possible relationships between soil properties and understory standing biomass.Area of study: Three monoespecific Quercus forests (Q. suber L., Q. ilex subsp. rotundifolia Lam. and Q. pyrenaica Willd in NE Portugal.Material and methods: During 1999 and 2000 soil properties (pH-KCl, total soil nitrogen (N, soil organic carbon (SOC, C/N ratio, available phosphorus (P, and available potassium (K and herbaceous biomass production of three forest types: Quercus suber L., Quercus ilex subsp. rotundifolia Lam. and Quercus pyrenaica Willd were studied.Main results: The results showed a different pattern of soil fertility (N, SOC, P, K in Quercus forests in NE of Portugal. The C/N ratio and the herbaceous biomass confirmed this pattern. Research highlights: There is a pattern of Quercus sp. distribution that correlates with different soil characteristics by soil characteristics in NE Portugal. Q. pyrenaica ecosystems were found in more favoured areas (mesic conditions; Q. rotundifolia developed in nutrient-poor soils (oligotrophic conditions; and Q. suber were found in intermediate zones.Keywords: fertility; biomass; C/N ratio; cork oak; holm oak; pyrenean oak.

  8. Evergreen sclerophyllous Quercus forests in northwestern Yunnan, China as compared to the Mediterranean evergreen Quercus forests in California, USA and northeastern Spain

    Directory of Open Access Journals (Sweden)

    C. Q. Tang

    2006-12-01

    Full Text Available Evergreen sclerophyllous Quercus forests in NW Yunnan (China were studied and compared with the Mediterranean evergreen sclerophyllous Quercus forests in central coastal California (USA and Catalonia (NE Spain. Forests of Q. aquifolioides, Q. pannosa, Q. longispica of NW Yunnan, Q. agrifolia of California and Q. ilex of NE Spain were analyzed as representative communities. The similarities and differences at the community level in the contemporary vegetation of the sclerophyllous Quercus forest found in the three regions are clarified. The general patterns of the evergreen Quercus forest in the three regions were similar, though different assemblages of species were involved. The species diversity in all three regions was rather low. The species richness did not significantly differ among the forests, although in the Q. longispica forest it is somewhat higher than the others. The three representative species of evergreen Quercus in NW Yunnan reached the greatest maximum height, while Q. agrifolia of California had the largest basal area per ha. The Q. ilex forest of Spain had the lowest values for maximum tree height and dbh and the highest density per ha. Frequency of dbh size classes indicated that Q. aquifolioides, Q. pannosa, and Q. agrifolia had potentially good regeneration of the sporadic type with highest values for the intermediate size classes, and the regeneration of Q. longispica and Q. ilex was strong as indicated by a reverse-J pattern. Still, in each area, most regeneration was from sprouting. In all three regions the evergreen Quercus species have adapted to environmental changes, for instance by development of sprouting and rooting abilities to resist drought, cold conditions and various disturbances. The evergreen Quercus forests in NW Yunnan were structurally more similar to the Q. agrifolia forest of central coastal California than to the Q. ilex forest of NE Spain.

  9. 5 CFR 630.503 - Leave from former leave systems.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Leave from former leave systems. 630.503... AND LEAVE Recredit of Leave § 630.503 Leave from former leave systems. An employee who earned leave under the leave acts of 1936 or any other leave system merged under subchapter I of chapter 63 of...

  10. Catalytic Rapid Pyrolysis of Quercus variabilis over Nanoporous Catalysts

    Directory of Open Access Journals (Sweden)

    Hyeon Koo Kang

    2015-01-01

    Full Text Available Catalytic rapid pyrolysis of Quercus variabilis, a Korean native tree species, was carried out using Py-GC/MS. Mesoporous MFI, which has both nanopores and micropores, and three nanoporous materials, Al-MCM-41, Al-SBA-15, and γ-Al2O3, were used as the catalyst. The acid sites of mesoporous MFI were strong Brønsted acid sites, whereas those of nanoporous materials were mostly weak acid sites. The composition of the product bio-oil varied greatly depending on the acid characteristics of the catalyst used. Phenolics were the most abundant species in the bio-oil, followed by acids and furanics, obtained over Al-MCM-41 or Al-SBA-15 with weak acid sites, whereas aromatics were the most abundant species produced over mesoporous MFI with strong acid sites, followed by phenolics. Aromatics, phenolics, and furanics are all important chemicals contributing to the improvement of bio-oil quality.

  11. Antimutagenicity of a suberin extract from Quercus suber cork.

    Science.gov (United States)

    Krizková, L; Lopes, M H; Polónyi, J; Belicová, A; Dobias, J; Ebringer, L

    1999-12-13

    The possible protective effect of a suberin extract from Quercus suber cork on acridine orange (AO)-, ofloxacin- and UV radiation-induced mutagenicity (bleaching activity) in Euglena gracilis was examined. To our knowledge, the present results are the first attempt to analyse suberin in relation to mutagenicity of some chemicals. Suberin exhibits a significant dose-dependent protective effect against AO-induced mutagenicity and the concentration of 500 micrograms/ml completely eliminates the Euglena-bleaching activity of AO. The mutagenicity of ofloxacin is also significantly reduced in the presence of suberin (125, 250 and 500 micrograms/ml). However, the moderate protective effect of suberin on UV radiation-induced mutagenicity was observed only at concentrations 500 and 1000 micrograms/ml. Our data shows that suberin extract from Q. suber cork possess antimutagenic properties and can be included in the group of natural antimutagens acting in a desmutagenic manner.

  12. Resprouting of Quercus suber in NE Spain after fire

    Energy Technology Data Exchange (ETDEWEB)

    Pausas, J.G. [Centro de Estudios Ambientales del Mediterraneo, Valencia (Spain)

    1997-11-01

    Many Mediterranean species have evolved strategies that allow them to survive periodic wildfires. Quercus suber trees resprout after fire, some from stem buds and others from basal buds only. In the former case the canopy recovers quickly. In the latter case the stem dies but the tree survives and regrows from basal sprouts. The probability of stem death and the degree of height recovery were studied after a fire in a Q. suber forest in NE Spain using logistic regression analysis. The results suggest that most trees survive after fire; the probability of stem death is negatively related to tree diameter; and recovery is positively related to tree diameter and to bark thickness. Implication for management and conservation of cork-oak forests are discussed 22 refs, 2 figs, 3 tabs

  13. 从藜豆中提取天然黑色素的工艺研究%Study on the extraction of natural melanin from mucuna macrocarpa wall

    Institute of Scientific and Technical Information of China (English)

    陈松; 韦万兴; 刘志平; 周敏; 卓家雄; 肖世基

    2011-01-01

    The extraction of natural melanin from mucuna macrocarpa wall was studied. Based on the experiment, the melanin was suitable to be extracted with 4% NaOH at 60 t for 40 min,precipitated when pH was 2. After further purification,3.62% yield of melanin was obtained. With UV and IR analysis,the melanin has the structure model of catechol.%以我国南方资源丰富的藜豆为原料,对藜豆中的天然黑色素提取工艺进行了研究,得出了藜豆黑色素的最佳提取条件:用4% NaOH溶液于60℃超声浸提40 min,调节pH =2,析出黑色素,得率为3.62%.由紫外和红外波谱分析藜豆黑色素具有邻苯二酚型结构.

  14. 马拉巴栗疫病病原的分离与鉴定%Isolation and Identification of the Pathogen Causing Phytophthora Blight of Pachira macrocarpa

    Institute of Scientific and Technical Information of China (English)

    李琳; 陈鸿宇; 柳凤; 何红; 余莎

    2011-01-01

    The diseased plants of Pachira macrocarpa showing symptoms of phytophthora blight were collected from Zhanjiang,Guangdong Province from 2008 to 2009.This study proved that the pathogen was a kind of fungus by test of Koch’s postulates.The pathogenic fungus was identified as Phytophthora palmivora based on pathogenicity and morphology,host range and sequence analysis of rDNA-ITS.%2008—2009年,从广东省湛江等地采集疑似疫病的马拉巴栗病株,经病原菌分离及柯赫氏法则验证,证明其病原菌是疫霉菌。通过致病性、寄主范围测定,菌体形态,培养特性及rDNA-ITS序列分析等,将该病原菌初步鉴定为棕榈疫霉(Phytophthora palmivora)。

  15. Juniperus oxycedrus L. subsp. oxycedrus and Juniperus oxycedrus L. subsp. macrocarpa (Sibth. & Sm.) Ball. "berries" from Turkey: comparative evaluation of phenolic profile, antioxidant, cytotoxic and antimicrobial activities.

    Science.gov (United States)

    Taviano, Maria Fernanda; Marino, Andreana; Trovato, Ada; Bellinghieri, Valentina; Melchini, Antonietta; Dugo, Paola; Cacciola, Francesco; Donato, Paola; Mondello, Luigi; Güvenç, Ayşegül; De Pasquale, Rita; Miceli, Natalizia

    2013-08-01

    This work aimed to evaluate and compare the phenolic profile and some biological properties of the ripe "berries" methanol extracts of Juniperus oxycedrus L. subsp. oxycedrus (Joo) and Juniperus oxycedrus L. subsp. macrocarpa (Sibth. & Sm.) Ball. (Jom) from Turkey. The total phenolic content resulted about 3-fold higher in Jom (17.89±0.23 mg GAE/g extract) than in Joo (5.14±0.06 mg GAE/g extract). The HPLC-DAD-ESI-MS analysis revealed a similar flavonoid fingerprint in Joo and Jom, whereas a difference in their quantitative content was found (4632 μg/g extract and 12644 μg/g extract). In addition, three phenolic acids were detected in Jom only (5765 μg/g extract), and protocatechuic acid was the most abundant one. The antioxidant capacity of the extracts was evaluated by different in vitro assays: in the DPPH and in the TBA tests a stronger activity in Jom was highlighted, while Joo exhibited higher reducing power and metal chelating activity. Joo and Jom did not affect HepG2 cell viability and both extracts resulted virtually non-toxic against Artemia salina. The extracts were also studied for their antimicrobial potential, displaying efficacy against Gram-positive bacteria. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Leaf N and P stoichiometry in relation to leaf shape and plant size for Quercus acutissima provenances across China.

    Science.gov (United States)

    Zhang, Hui; Yang, Xiuqing; Wang, Jingyuan; Wang, G Geoff; Yu, Mukui; Wu, Tonggui

    2017-04-10

    Plant stoichiometry in relation to the structure and function of biological systems has been investigated at multiple scales. However, few studies have focused on the roles of stoichiometry for a given species. In this study, we determined leaf N and P stoichiometry, leaf shape and plant size in three Quercus acutissima common gardens with different climatic and site conditions. In the three common gardens, leaf N and P stoichiometry was significantly correlated with leaf shape and plant size, suggesting that leaf N and P stoichiometry affects the morphological performance of the leaves and stem. The scaling slopes of the relationships between leaf N and P stoichiometry and leaf shape ranged from |0.12| to |1.00|, while the slopes of the relationships between leaf N and P stoichiometry and plant size ranged from |0.95| to |2.66|. These results suggest that non-functional tissues (stem) are more susceptible to leaf nutrition than functional tissues (leaves), and leaf stoichiometry is more important in the construction of non-functional tissues (stem). Between the northernmost and southernmost common gardens, leaf N and leaf width (W), N:P and stem height (H), and N:P and stem diameter (D) showed significant covariations, which indicates that leaf N and W, N:P and plant size exhibit similar plastic responses to environmental change.

  17. Moisture sorption isotherms and thermodynamic properties of Oak wood ( Quercus robur and Quercus canariensis): optimization of the processing parameters

    Science.gov (United States)

    Bahar, Rim; Azzouz, Soufien; Remond, Romain; Ouertani, Sahbi; Elaieb, Mohamed Taher; El Cafci, Mohamed Afif

    2017-05-01

    The aim of this paper was to determine the moisture desorption isotherms and essentials thermodynamic properties of two Oak wood varieties. Desorption isotherms were measured using a static gravimetric method at 50, 60, 70 and 80 °C within the range of 5-90 % relative humidity. The equilibrium moisture content decreased with increasing temperature and decreased with decreasing relative humidity at a constant temperature. The `Thermodynamic' sorption equation was found to be the best for describing the experimental moisture sorption isotherms of woods within the range of temperature and water activity investigated. The Fiber saturation point, deduced from the `Thermodynamic' model parameters, depends on the temperature and varying from 22.6 to 54.4 (% kg water/kg dry matter). Isosteric heat of desorption and differential entropy were calculated by applying Clausius-Clapeyron equation to the desorption data fitted by the `Thermodynamic' model. The isosteric heat of desorption and the differential entropy decreased with increasing moisture content according to an exponential law equation and varying from 2.03 to 31.14 kJ/mol and from 73.98 to 4.34 J/(mol K), respectively. The linear relationship between differential enthalpy and entropy satisfied the enthalpy-entropy compensation theory. The sign of Gibbs free energy was found to be positive (+283 J/mol) and (+97 J/mol) for Quercus robur and Quercus canariensis, respectively. The isokinetic temperature was found to be greater than the harmonic temperature. Based on the enthalpy-entropy compensation theory, it could be concluded that the moisture desorption isotherm of Oak wood is a non-spontaneous and enthalpy-controlled process.

  18. Moisture sorption isotherms and thermodynamic properties of Oak wood (Quercus robur and Quercus canariensis): optimization of the processing parameters

    Science.gov (United States)

    Bahar, Rim; Azzouz, Soufien; Remond, Romain; Ouertani, Sahbi; Elaieb, Mohamed Taher; El Cafci, Mohamed Afif

    2016-09-01

    The aim of this paper was to determine the moisture desorption isotherms and essentials thermodynamic properties of two Oak wood varieties. Desorption isotherms were measured using a static gravimetric method at 50, 60, 70 and 80 °C within the range of 5-90 % relative humidity. The equilibrium moisture content decreased with increasing temperature and decreased with decreasing relative humidity at a constant temperature. The `Thermodynamic' sorption equation was found to be the best for describing the experimental moisture sorption isotherms of woods within the range of temperature and water activity investigated. The Fiber saturation point, deduced from the `Thermodynamic' model parameters, depends on the temperature and varying from 22.6 to 54.4 (% kg water/kg dry matter). Isosteric heat of desorption and differential entropy were calculated by applying Clausius-Clapeyron equation to the desorption data fitted by the `Thermodynamic' model. The isosteric heat of desorption and the differential entropy decreased with increasing moisture content according to an exponential law equation and varying from 2.03 to 31.14 kJ/mol and from 73.98 to 4.34 J/(mol K), respectively. The linear relationship between differential enthalpy and entropy satisfied the enthalpy-entropy compensation theory. The sign of Gibbs free energy was found to be positive (+283 J/mol) and (+97 J/mol) for Quercus robur and Quercus canariensis, respectively. The isokinetic temperature was found to be greater than the harmonic temperature. Based on the enthalpy-entropy compensation theory, it could be concluded that the moisture desorption isotherm of Oak wood is a non-spontaneous and enthalpy-controlled process.

  19. Seasonal dynamics of secondary growth and xylem anatomy in two coexisting Mediterranean Quercus; Dinamica estacional del crecimiento secundario y anatomia del xilema en dos Quercus mediterraneos que coexisten

    Energy Technology Data Exchange (ETDEWEB)

    Albuixech, J.; Camarero, J. J.; Montserrat-Marti, G.

    2012-11-01

    The contribution of secondary growth's patterns and wood anatomy on the coexistence of two species of Quercus (Quercus ilex subsp ballota diffused porous wood and Quercus faginea ring porous wood) were studied in a location with continental Mediterranean climate, which has been studied during two years with contrasted climatology. According to our results secondary growth pattern of Q. faginea is concentrated in the spring, starting before, and responding more than Q. ilex to a rainfall increase during this period. Q. ilex extends wood formation into the fall and late summer growth. Q. ilex growth during the fall and late summer has a greater importance in terms of theoretical hydraulic conductivity than in Q. faginea, which concentrates hydraulic conductivity in spring vessels. Therefore, different response of wood phenology formation and xylem anatomy in both species to the seasonal pattern of precipitation could contribute to explain the coexistence of Q. ilex and Q. faginea. (Author) 48 refs.

  20. Tvorba marketingovej stratégie internetového obchodu Quercus

    OpenAIRE

    Krahulcová, Lenka

    2011-01-01

    Diploma thesis is focused on creation of new marketing strategy for company QUERCUS' electronic store. Theoretical part deals with basic concepts of marketing and strategic marketing planning. It further introduces marketing mix specifics on the internet, basic aspects of electronic commerce and consumer behavior on internet. Practical part includes introduction of company QUERCUS, e-shop SWOT analysis, brief characteristic of current marketing strategy and finally proposal of new marketing s...

  1. Effects of cadmium on cork oak (Quercus suber L.) plants grown in hydroponics.

    Science.gov (United States)

    Gogorcena, Yolanda; Larbi, Ajmi; Andaluz, Sofia; Carpena, Ramón O; Abadía, Anunciación; Abadía, Javier

    2011-12-01

    Cork oak (Quercus suber L.) is an autochthonous tree species that is being used for reforestation in heavy-metal-contaminated areas in Spain. A hydroponics experiment was carried out to characterize the effects of Cd on several morphological and physiological parameters in this species, including shoot length, nutrient concentrations and allocation in different organs, leaf pigment concentrations, photosynthetic efficiency, root ferric chelate reductase (FCR) activity and organic acid concentrations in xylem sap. Four different Cd treatments were applied, adding Cd chelated with EDTA or as chloride salt at two different concentrations (10 and 50 µM Cd). After 1 month of Cd treatment, plant growth was significantly inhibited in all treatments. Results indicate that Cd accumulates in all organs 7- to 500-fold when compared with control plants. The highest Cd concentration was found in the 50 µM CdCl(2) treatment, which led to concentrations of ~30, 123 and 1153 µg Cd g(-1) dry weight in leaves, stems and roots, respectively. In the strongest Cd treatments the concentrations of P and Ca decreased in some plant parts, whereas the Mn leaf concentrations decreased with three of the four Cd treatments applied. The concentrations of chlorophyll and carotenoids on an area basis decreased, whereas the (zeaxanthin plus antheraxanthin)/(total violaxanthin cycle carotenoids) ratio and the non-photochemical quenching increased significantly in all Cd treatments. Cadmium treatments caused significant increases in the activity of the enzyme FCR in roots and in the concentrations of organic acids in xylem sap. Some of the physiological changes found support the fact that Cd induces a deficiency of Fe in cork oak, although the plant Fe concentrations were not reduced significantly. At higher concentrations the effects of Cd were more pronounced, and were more marked when Cd was in the free ion form than when present in the form of Cd-EDTA.

  2. Molecular characterization of Quercus suber MYB1, a transcription factor up-regulated in cork tissues.

    Science.gov (United States)

    Almeida, Tânia; Menéndez, Esther; Capote, Tiago; Ribeiro, Teresa; Santos, Conceição; Gonçalves, Sónia

    2013-01-15

    The molecular processes associated with cork development in Quercus suber L. are poorly understood. A previous molecular approach identified a list of genes potentially important for cork formation and differentiation, providing a new basis for further molecular studies. This report is the first molecular characterization of one of these candidate genes, QsMYB1, coding for an R2R3-MYB transcription factor. The R2R3-MYB gene sub-family has been described as being involved in the phenylpropanoid and lignin pathways, both involved in cork biosynthesis. The results showed that the expression of QsMYB1 is putatively mediated by an alternative splicing (AS) mechanism that originates two different transcripts (QsMYB1.1 and QsMYB1.2), differing only in the 5'-untranslated region, due to retention of the first intron in one of the variants. Moreover, within the retained intron, a simple sequence repeat (SSR) was identified. The upstream regulatory region of QsMYB1 was extended by a genome walking approach, which allowed the identification of the putative gene promoter region. The relative expression pattern of QsMYB1 transcripts determined by reverse transcription quantitative polymerase chain reaction (RT-qPCR) revealed that both transcripts were up-regulated in cork tissues; the detected expression was several times higher in newly formed cork harvested from trees producing virgin, second or reproduction cork when compared with wood. Moreover, the expression analysis of QsMYB1 in several Q. suber organs showed very low expression in young branches and roots, whereas in leaves, immature acorns or male flowers, no expression was detected. These preliminary results suggest that QsMYB1 may be related to secondary growth and, in particular, with the cork biosynthesis process with a possible alternative splicing mechanism associated with its regulatory function.

  3. Reference gene selection for quantitative real-time PCR normalization in Quercus suber.

    Science.gov (United States)

    Marum, Liliana; Miguel, Andreia; Ricardo, Cândido P; Miguel, Célia

    2012-01-01

    The use of reverse transcription quantitative PCR technology to assess gene expression levels requires an accurate normalization of data in order to avoid misinterpretation of experimental results and erroneous analyses. Despite being the focus of several transcriptomics projects, oaks, and particularly cork oak (Quercus suber), have not been investigated regarding the identification of reference genes suitable for the normalization of real-time quantitative PCR data. In this study, ten candidate reference genes (Act, CACs, EF-1α, GAPDH, His3, PsaH, Sand, PP2A, ß-Tub and Ubq) were evaluated to determine the most stable internal reference for quantitative PCR normalization in cork oak. The transcript abundance of these genes was analysed in several tissues of cork oak, including leaves, reproduction cork, and periderm from branches at different developmental stages (1-, 2-, and 3-year old) or collected in different dates (active growth period versus dormancy). The three statistical methods (geNorm, NormFinder, and CV method) used in the evaluation of the most suitable combination of reference genes identified Act and CACs as the most stable candidates when all the samples were analysed together, while ß-Tub and PsaH showed the lowest expression stability. However, when different tissues, developmental stages, and collection dates were analysed separately, the reference genes exhibited some variation in their expression levels. In this study, and for the first time, we have identified and validated reference genes in cork oak that can be used for quantification of target gene expression in different tissues and experimental conditions and will be useful as a starting point for gene expression studies in other oaks.

  4. Reference gene selection for quantitative real-time PCR normalization in Quercus suber.

    Directory of Open Access Journals (Sweden)

    Liliana Marum

    Full Text Available The use of reverse transcription quantitative PCR technology to assess gene expression levels requires an accurate normalization of data in order to avoid misinterpretation of experimental results and erroneous analyses. Despite being the focus of several transcriptomics projects, oaks, and particularly cork oak (Quercus suber, have not been investigated regarding the identification of reference genes suitable for the normalization of real-time quantitative PCR data. In this study, ten candidate reference genes (Act, CACs, EF-1α, GAPDH, His3, PsaH, Sand, PP2A, ß-Tub and Ubq were evaluated to determine the most stable internal reference for quantitative PCR normalization in cork oak. The transcript abundance of these genes was analysed in several tissues of cork oak, including leaves, reproduction cork, and periderm from branches at different developmental stages (1-, 2-, and 3-year old or collected in different dates (active growth period versus dormancy. The three statistical methods (geNorm, NormFinder, and CV method used in the evaluation of the most suitable combination of reference genes identified Act and CACs as the most stable candidates when all the samples were analysed together, while ß-Tub and PsaH showed the lowest expression stability. However, when different tissues, developmental stages, and collection dates were analysed separately, the reference genes exhibited some variation in their expression levels. In this study, and for the first time, we have identified and validated reference genes in cork oak that can be used for quantification of target gene expression in different tissues and experimental conditions and will be useful as a starting point for gene expression studies in other oaks.

  5. Ecophysiological characteristics and cadmium accumulation in Downy Oak (Quercus pubescens Willd.

    Directory of Open Access Journals (Sweden)

    Cocozza C

    2012-10-01

    Full Text Available Heavy metals provoke environmental pollution with potentially toxic effects on human and plants systems. Recently, investigations are conducted on plants that may play a relevant role on pollutants absorption or stabilization, focusing on fast growing tree species in agronomic conditions; little is known on the effects of contaminants on tree species colonizing abandoned fields to be used in restoration ecology. The effects of Cd on photosynthetic performance and metal accumulation were investigated in Quercus pubescens Willd. seedlings grown in pots containing a mixture of sand, clay, turf and Cd-treatments (0, 25 and 75 mg kg-1 dry soil. The studied photosynthetic parameters (Asat= net phytosynthesis; Rday= day respiration; Γcomp= CO2 compensation point; Vcmax= maximum carboxylation rate; Jmax = electron transport rate; TPU = triose phosphate use; Ci/Ca = ratio of intercellular (Ci to ambient (Ca [CO2] (Ci/Ca; Jmax/Vcmax = ratio; (gsmax = maximum stomatal conductance; (lg = stomatal conductance estimated relative to the photosynthetic rate; (Fv/Fm = maximum quantum yield of PSII photochemistry; (ΔF/F’m = effective photochemical efficiency varied progressively with increasing Cd concentration in the soil, highlighting a negative impact on photosynthetic potential and PSII functioning. Approximately 10% of added Cd was found to be extractable from the substrate, at the maximum concentration applied, with about 12 and 0.75 as bioaccumulation and translocation factors, respectively. Analogously, Cd accumulated up to 34, 30 and 46 mg kg−1 in leaves, stem and roots, respectively. While it is not possible to extrapolate from the present study with seedlings to effects on mature pine trees, there are clear implications for regeneration in soils contaminated with heavy metals, which may lead to ecosystem deterioration.

  6. Phaleria macrocarpa (Boerl.) fruit induce G0/G1 and G2/M cell cycle arrest and apoptosis through mitochondria-mediated pathway in MDA-MB-231 human breast cancer cell.

    Science.gov (United States)

    Kavitha, Nowroji; Ein Oon, Chern; Chen, Yeng; Kanwar, Jagat R; Sasidharan, Sreenivasan

    2017-04-06

    Phaleria macrocarpa (Scheff) Boerl, is a well-known folk medicinal plant in Indonesia. Traditionally, P. macrocarpa has been used to control cancer, impotency, hemorrhoids, diabetes mellitus, allergies, liver and hearth disease, kidney disorders, blood diseases, acne, stroke, migraine, and various skin diseases. The purpose of this study was to determine the in situ cytotoxicity effect P. macrocarpa fruit ethyl acetate fraction (PMEAF) and the underlying molecular mechanism of cell death. MDA-MB-231 cells were incubated with PMEAF for 24h. Cell cycle and viability were examined using flow cytometry analysis. Apoptosis was determined using the Annexin V assay and also by fluorescence microscopy. Apoptosis protein profiling was detected by RayBio® Human Apoptosis Array. The AO/PI staining and flow cytometric analysis of MDA-MB-231 cells treated with PMEAF were showed apoptotic cell death. The cell cycle analysis by flow cytometry analysis revealed that the accumulation of PMEAF treated MDA-MB-231 cells in G0/G1 and G2/M-phase of the cell cycle. Moreover, the PMEAF exert cytotoxicity by increased the ROS production in MDA-MB-231 cells consistently stimulated the loss of mitochondrial membrane potential (∆Ψm) and induced apoptosis cell death by activation of numerous signalling proteins. The results from apoptosis protein profiling array evidenced that PMEAF stimulated the expression of 9 pro-apoptotic proteins (Bax, Bid, caspase 3, caspase 8, cytochrome c, p21, p27, p53 and SMAC) and suppressed the 4 anti-apoptotic proteins (Bcl-2, Bcl-w, XIAP and survivin) in MDA-MB-231 cells. The results indicated that PMEAF treatment induced apoptosis in MDA-MB-231 cells through intrinsic mitochondrial related pathway with the participation of pro and anti-apoptotic proteins, caspases, G0/G1 and G2/M-phases cell cycle arrest by p53-mediated mechanism. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

  7. Investigação dos efeitos citotóxico, genotóxico e antibacteriano dos taninos isolados de Anacardium Occidentale Linn e Anadenanthera Macrocarpa (Benth.) Brenan em linhagens de Streptococcus associados ao biofilme dental

    OpenAIRE

    Araújo, Josenildo Segundo Chaves de

    2013-01-01

    As plantas são uma rica fonte de novas moléculas biologicamente ativas com reconhecido potencial no desenvolvimento de medicamentos. O Anacardium occidentale Linn é popularmente conhecida como 'cajueiro', é uma planta da família das Anacardiaceae, originária do Nordeste do Brasil e popularmente conhecida por suas propriedades antiinflamatórias e cicatrizantes. O Anadenanthera macrocarpa (Benth.) Brenan ou o "angico" é pertencente a família das Mimosaceae, distribuída pelas r...

  8. Soil development in OSL dated sandy dune substrates under Quercus robur Forest (Netherlands)

    Science.gov (United States)

    van Mourik, J. M.; Nierop, Ir. K.; Verstraten, J. M.

    2009-04-01

    , the quercus pollen production is very low and other wind pollinated grains from dune grasses and shrubs can dominate the pollen spectra. Based upon OSL dates, a period of 200 year forest soil development is more reliable than the 14C based 45 year. We must reject the 14C ages, due to complexity of sources of soil organic matter in the Ah horizon The organic matter as investigated by analytical pyrolysis and thermally assisted hydrolysis and methylation and subsequent analysis by GC/MS revealed a major oak-derived picture. The L+F1 horizons reflected relatively undecomposed organic matter mainly derived from leaves. By contrast, in both F2+H and the Ah horizons leaf material was accompanied by root-derived components, particularly suberin. The latter may originate from barks as well, but in the Ah horizons the contribution of roots was most probably much greater. Apart from a common transformation pattern (decrease of polysaccharides, degradation of lignin and accumulation of lipids), a very small contribution of C26 alkanol indicated a chemical fingerprint of the previous grass vegetation. In conclusion: chemical analysis confirmed the soil micromorphological data, and the application of OSL dating improves our knowledge about geochronology of the system.

  9. Protective effect of Castanea sativa and Quercus robur leaf extracts against oxygen and nitrogen reactive species.

    Science.gov (United States)

    Almeida, Isabel F; Fernandes, Eduarda; Lima, José L F C; Costa, P C; Bahia, M F

    2008-05-29

    Topical natural antioxidants are a useful strategy for the prevention of photoaging and oxidative stress mediated skin diseases. In view of this underlying principle, the screening of natural plant extracts with scavenging activity for pro-oxidant reactive species is a primary requirement for the development of new topical antioxidant formulations. In the present study, an ethanol:water (7:3) extract from Castanea sativa leaves and a ethanol:water (2:3) extract from Quercus robur leaves were evaluated for their putative in vitro scavenging effects on reactive oxygen species (ROS) namely superoxide radical (O(2)(-)), hydroxyl radical (HO()), peroxyl radical (ROO()), hydrogen peroxide (H(2)O(2)) and singlet oxygen ((1)O(2)) as well as on reactive nitrogen species (RNS) namely nitric oxide (()NO) and peroxynitrite (ONOO(-)). The extracts presented a high potency to scavenge the tested reactive species, all the IC(50)s being found at the microg/mL level. IC(50)s (mean+/-SE) for the ROS O(2)(-),HO(),H(2)O(2) and (1)O(2) were 13.6+/-1.8; 216+/-4; 410+/-8; 12.3+/-0.7 microug/mL, respectively, for C. sativa, and 11.0+/-0.5; 285+/-22; 251+/-32; 7.90+/-0.56 microg/mL, respectively, for Q. robur. The ORAC values obtained for ROO() were 1.24+/-0.13 for C. sativa and 1.09+/-0.06 for Q. robur. The IC(50)s (mean+/-SE) for ()NO and ONOO(-) were 3.10+/-0.14 and 1.49+/-0.10 microg/mL, respectively, for C. sativa and 3.13+/-0.11 and 0.95+/-0.02 microg/mL, respectively, for Q. robur. The content of total phenolics for C. sativa and Q. robur were 284+/-9 and 346+/-4 mg of gallic acid equivalents (GAE)/g of lyophilized extract respectively. The observed effects might be of relevance considering the putative interest of these extracts as topical antioxidants.

  10. Potential Activity of Fevicordin-A from Phaleria macrocarpa (Scheff Boerl. Seeds as Estrogen Receptor Antagonist Based on Cytotoxicity and Molecular Modelling Studies

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    Muchtaridi Muchtaridi

    2014-04-01

    Full Text Available Fevicordin-A (FevA isolated from Phaleria macrocarpa (Scheff Boerl. seeds was evaluated for its potential anticancer activity by in vitro and in silico approaches. Cytotoxicity studies indicated that FevA was selective against cell lines of human breast adenocarcinoma (MCF-7 with an IC50 value of 6.4 µM. At 11.2 µM, FevA resulted in 76.8% cell death of T-47D human breast cancer cell lines. Critical pharmacophore features amongst human Estrogen Receptor-α (hERα antagonists were conserved in FevA with regard to a hypothesis that they could make notable contributions to its pharmacological activity. The binding stability as well as the dynamic behavior of FevA towards the hERα receptor in agonist and antagonist binding sites were probed using molecular dynamics (MD simulation approach. Analysis of MD simulation suggested that the tail of FevA was accountable for the repulsion of the C-terminal of Helix-11 (H11 in both agonist and antagonist receptor forms. The flexibility of loop-534 indicated the ability to disrupt the hydrogen bond zipper network between H3 and H11 in hERα. In addition, MM/GBSA calculation from the molecular dynamic simulations also revealed a stronger binding affinity of FevA in antagonistic action as compared to that of agonistic action. Collectively, both the experimental and computational results indicated that FevA has potential as a candidate for an anticancer agent, which is worth promoting for further preclinical evaluation.

  11. Photosynthetic activity of Fagus sylvatica L. and Quercus petraea (Matt Liebl. in a mixed stand at Maljen mountain

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    Popović Zorica

    2005-01-01

    Full Text Available Estimation of the photosynthetic performance of co-existing tree species with pronounced differences in ecophysiological context (Aranda et al. 1996 Leuschner et al. 2001 could provide insight into their vitality and competitive abilities at a particular site. Gas exchange, composition of photosynthetic pigments, and the water status of beech (Fagus sylvatica L and sessile oak (Quercus petraea (Matt Liebl were studied in the present work. The investigation was performed on Mt. Maljen (Western Serbia, near the town of Mionica at an altitude of 950 m, in an ecotope within the confines of the mountain's beech forest belt. Codominant samplings [three of each species, 30-years old (n=6, 10-12 m high] were selected for the measurements, which were conducted on fully developed leaves from the out­ermost branches and from the innermost canopy. Photosynthetic measurements were performed using an LI-6200 closed photo­synthesis system (LI-Cor. Inc, Lincoln, NE, USA, while irradiance was detected with a selenium cell mounted on the leaf chamber. Parameters of gas exchange are expressed on the basis of leaf area, using the AREAMETER software (Karadžić et al. 1999. Chlorophyll content was spectrophotometrically determined based on light absorption of the solution obtained after extraction with dMSO (Hiscox and Israelstam, 1979. The midday water saturation deficit was determined according to Turner (1981. For data analysis, we used the Statistic for Windows program package. The ANOVA one-way break­down was applied to compare differences within (leaves inside vs. leaves outside the surface of the tree canopy and between species for all investigated parameters at the 0.05 level of significance.

  12. Responses and acclimation of Chinese cork oak (Quercus variabilis Bl.) to metal stress: the inducible antimony tolerance in oak trees.

    Science.gov (United States)

    Zhao, Xiulian; Zheng, Lingyu; Xia, Xinli; Yin, Weilun; Lei, Jingpin; Shi, Shengqing; Shi, Xiang; Li, Huiqing; Li, Qinghe; Wei, Yuan; Chang, Ermei; Jiang, Zeping; Liu, Jianfeng

    2015-08-01

    Antimony (Sb) pollution has become a pressing environmental problem in recent years. Trees have been proven to have great potential for the feasible phytomanagement; however, little is known about Sb retention and tolerance in trees. The Chinese cork oak (Quercus variabilis Bl.) is known to be capable of growth in soils containing high concentrations of Sb. This study explored in detail the retention and acclimation of Q. variabilis under moderate and high external Sb levels. Results revealed that Q. variabilis could tolerate and accumulate high Sb (1623.39 mg kg(-1) DW) in roots. Dynamics of Sb retention in leaves, stems, and roots of Q. variabilis were different. Leaf Sb remained at a certain level for several weeks, while in roots and stems, Sb concentrations continued to increase. Sb damaged tree's PSII reaction cores but elicited defense mechanism at the donor side of PSII. It affected the electron transport flow after QA (-) more strongly than the oxygen-evolving complex and light-harvesting pigment-protein complex II. Sb also decreased leaf chlorophyll concentrations and therefore inhibited plant growth. During acclimation to Sb toxicity, Sb concentrations in leaves, stems, and roots decreased, with photosynthetic activity and pigments recovering to normal levels by the end of the experiment. These findings suggest that Sb tolerance in Q. variabilis is inducible. Acclimation seems to be related to homeostasis of Sb in plants. Results of this study can provide useful information for trees breeding and selection of Sb phytomanagement strategies, exploiting the established ability of Q. variabilis to transport, delocalize in the leaves, and tolerate Sb pollutions.

  13. Leaf morphological variability and intraspecific taxonomic units for pedunculate oak and grayish oak (genus Quercus L., series Pedunculatae Schwz.) in Southern Carpathian Region (Romania).

    Science.gov (United States)

    Apostol, Ecaterina Nicoleta; Curtu, Alexandru Lucian; Daia, Liviu Mihai; Apostol, Bogdan; Dinu, Cristiana Georgeta; Şofletea, Neculae

    2017-07-26

    Even though pedunculate oak (Quercus robur L.) and grayish oak (Quercus pedunculiflora K. Koch) have different ecological requirements, they have been considered as having low differentiation at the level of morphological traits and genetic variation. The leaf morphology for 862 trees has been assessed in 16 natural populations, seven of Q. robur, eight of Q. pedunculiflora and a mixed forest were both taxa coexist. In total, fifteen descriptors have been analysed by using discriminant analysis, while it was found that with only four out of the fifteen leaf traits (abaxial pubescence, abaxial colour of the leaf, petiole length and basal shape of lamina) the two taxa could be clearly differentiated. A dendrogram has been constructed on the basis of these traits, where the populations of each taxon have been clustered together. PU and CL traits of Q. pedunculiflora were discussed for their adaptive value for drought resistance in the steppe habitats occupied by this taxon. Using the leaves' morphological descriptors and data from the literature, intra-taxonomic units (varieties, forms and sub-forms) have been identified in all analysed populations. Eight intraspecific units for Q. robur and six for Q. pedunculiflora have been identified in the investigated area. An analysis of spatial distribution of the two taxa and of their intraspecific units has been performed using maps of ecoregions for the study area. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Microsatellite Primer Development for Post Oak, Quercus stellata (Fagaceae

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    Warren B. Chatwin

    2014-10-01

    Full Text Available Premise of the study: The American Cross Timbers forest ecosystem runs from southeastern Kansas to Central Texas and is primarily composed of post oak (Quercus stellata. This old-growth forest currently occupies only about 2% of its ancestral range. To facilitate genetic research on this species, we developed microsatellite primers specific to post oak from reduced genomic libraries. Methods and Results: Two Q. stellata individuals, sampled from the northern and southern range of the post oak forest, were subject to genomic reduction and 454 pyrosequencing. Bioinformatic analysis identified putative microsatellites from which 12 polymorphic primer sets were screened on three populations. The number of alleles observed ranged from five to 20 across all populations, while observed and expected heterozygosity values ranged from 0.05 to 0.833 and 0.236 to 0.893, respectively, within individual populations. Conclusions: We report the development of microsatellite markers, specific to post oak, to aid the study of genetic diversity and population structure of extant forest remnants.

  15. Mycorrhizas on nursery and field seedlings of Quercus garryana.

    Science.gov (United States)

    Southworth, Darlene; Carrington, Elizabeth M; Frank, Jonathan L; Gould, Peter; Harrington, Connie A; Devine, Warren D

    2009-03-01

    Oak woodland regeneration and restoration requires that seedlings develop mycorrhizas, yet the need for this mutualistic association is often overlooked. In this study, we asked whether Quercus garryana seedlings in nursery beds acquire mycorrhizas without artificial inoculation or access to a mycorrhizal network of other ectomycorrhizal hosts. We also assessed the relationship between mycorrhizal infection and seedling growth in a nursery. Further, we compared the mycorrhizal assemblage of oak nursery seedlings to that of conifer seedlings in the nursery and to that of oak seedlings in nearby oak woodlands. Seedlings were excavated and the roots washed and examined microscopically. Mycorrhizas were identified by DNA sequences of the internal transcribed spacer region and by morphotype. On oak nursery seedlings, predominant mycorrhizas were species of Laccaria and Tuber with single occurrences of Entoloma and Peziza. In adjacent beds, seedlings of Pseudotsuga menziesii were mycorrhizal with Hysterangium and a different species of Laccaria; seedlings of Pinus monticola were mycorrhizal with Geneabea, Tarzetta, and Thelephora. Height of Q. garryana seedlings correlated with root biomass and mycorrhizal abundance. Total mycorrhizal abundance and abundance of Laccaria mycorrhizas significantly predicted seedling height in the nursery. Native oak seedlings from nearby Q. garryana woodlands were mycorrhizal with 13 fungal symbionts, none of which occurred on the nursery seedlings. These results demonstrate the value of mycorrhizas to the growth of oak seedlings. Although seedlings in nursery beds developed mycorrhizas without intentional inoculation, their mycorrhizas differed from and were less species rich than those on native seedlings.

  16. Presence of env-like sequences in Quercus suber retrotransposons.

    Science.gov (United States)

    Carvalho, M; Ribeiro, T; Viegas, W; Morais-Cecilio, L; Rocheta, M

    2010-01-01

    The main difference between LTR retrotransposons and retroviruses is the presence of the envelope (env) gene in the latter, downstream of the pol gene. The env gene is involved in their infectious capacity. Here we report the presence of env-like sequences in the genome of Quercus suber (cork oak), one of the most economically important Portuguese species. These gene sequences were isolated through DNA amplification between RNaseH conserved motifs and 3' LTR, based on the structure of copia retrotransposons. Phylogenetic analysis revealed that almost all the clones isolated are clustered with Cyclops-2, a Ty3-gypsy element identified in Pisum sativum, except one clustered with gypsy and copia retroelements found in different species. This suggests the existence of a potential ancestral sequence of the env gene, prior to the separation of Ty3-gypsy and Ty1-copia retrotransposons. Additionally, the isolated env-like sequences showed 26-39% of homology with env-like sequences characterized in viruses. The origin of env-like sequences in retrotransposons from host plant taxa is discussed.

  17. Pharmacognostic studies of insect gall of Quercus infectoria Olivier (Fagaceae)

    Institute of Scientific and Technical Information of China (English)

    Savitri Shrestha; Vasuki Srinivas Kaushik; Ravi Shankara Birur Eshwarappa; Sundara Rajan Subaramaihha; Latha Muuaiah Ramanna; Dhananjaya Bhadrapura Lakkappa

    2014-01-01

    Objective:To study the detailed pharmacognostic profile of galls of Quercus infectoria Olivier (Q. infectoria olivier) (Fagaceae), an important medicinal plant used in the Indian system of medicine. Methods: Samples of galls of Q. infectoria were studied by macroscopical, microscopical, physiochemical, phytochemical, fluorescence analysis and othjer methods for standardization as recommended by WHO. Results:Macroscopically, the crude drug is globose with horny appearances on external surface (1.4-2.3 cm in length and 1-1.5 cm in diameter), with greyish-brown to brownish-black in colour externally and dark brown buff colored. Surface is smooth with numerous horny protuberances giving rough touch, and with unpleasant odour. Microscopically, a wide zone of radially elongated parenchyma cells between upper and lower epidermis were found. The vascular strands were present at all places and radially elongated sclerides touched the lower epidermis. In physico-chemical studies, the moisture, total ash, acid insoluble ash, alcohol soluble, water soluble, petroleum ether, chloroform extractive value and tannin content were found to be 2.790, 5.020, 0.110, 38.780, 41.210, 0.402, 1.590 and 49.200 percentage respectively. Preliminary phytochemical screening showed the presence of phenols, flavonoids, steroids, triterpenes, tannins, saponins and alkaloids. Conclusions:The results of the present study serve as a valuable source of information and provide suitable standards for identification of this medicinally important plant drug material for future investigations and applications.

  18. Variability of acorn anatomical characteristics in Quercus robur L. genotypes

    Directory of Open Access Journals (Sweden)

    Nikolić Nataša P.

    2010-01-01

    Full Text Available The aim of this study was to examine variability of acorn anatomical characteristics in seventeen Quercus robur L. genotypes. Acorns were collected in clonal seed orchard Banov Brod (Srem, Vojvodina, Serbia. Microscopic measurements were done for pericarp (total thickness, thickness of exocarp and mesocarp, seed coat (total thickness, thickness of outer epidermis, parenchyma, and inner epidermis, and embryo axis (diameter, thickness of cortical region, and diameter of stellar zone. Obtained results revealed certain divergence between genotypes. The thickness of pericarp varied from 418 to 559 mm (genotypes 20 and 22, respectively. On average, the participation of exocarp in the total thickness of pericarp was 36.3%, of mesocarp 61.0%, while of endocarp 2.6%. The thickness of seed coat for individual genotypes ranged from 71 mm (genotype 28 to 157 mm (genotype 38. In addition, anatomic parameters of embryo axis varied among studied genotypes. The lowest cortical zone thickness and stellar zone diameter were measured in genotype 40, while the highest values in genotype 33.

  19. Effects of partial defoliation on carbon and nitrogen partitioning and photosynthetic carbon uptake by two-year-old cork oak (Quercus suber) saplings.

    Science.gov (United States)

    Cerasoli, S; Scartazza, A; Brugnoli, E; Chaves, M M; Pereira, J S

    2004-01-01

    At the end of the growing season in late July, 20-month-old cork oak (Quercus suber L.) saplings were partially defoliated (63% of leaf area) to evaluate their ability to recover leaf area after defoliation. At 18 and 127 days after defoliation, changes in starch and nitrogen pools were determined in leaves and perennial organs, and variations in photosynthetic carbon uptake were investigated. To determine the role of stored nitrogen in regrowth after defoliation, plant nitrogen was labeled in the previous winter by enriching the nutrient solution with 15N. Plants recovered the lost leaf area in 127 days. Although there was remobilization of starch and nitrogen from leaves and perennial organs, the availability of resources for growth in the following spring was not decreased by defoliation. On the contrary, starch concentration in coarse roots was higher in defoliated saplings than in control saplings, presumably as a result of the higher net CO2 exchange rate in newly developed leaves compared with pre-existing leaves.

  20. Goodbye, Mandatory Maternity Leaves

    Science.gov (United States)

    Nation's Schools, 1972

    1972-01-01

    In precedent-setting decrees, courts and federal and State authorities have branded compulsory maternity leaves either unconstitutional or illegal. School administrators are urged to prod boards of education to adopt more lenient maternity leave policies -- now. (Author)

  1. SAVED LEAVE BONUS

    CERN Multimedia

    Division des ressources humaines

    2000-01-01

    Staff members participating in the RSL programme are entitled to one additional day of saved leave for each full period of 20 days remaining in their saved leave account on 31 December 1999.Allowing some time for all concerned to make sure that their periods of leave taken in 1999 are properly registered, HR division will proceed with the crediting of the appropriate number of days in the saved leave accounts from 25 January 2000.Human Resources DivisionTel.73359

  2. Parental leave in Belgium

    OpenAIRE

    Maron, Leila; Meulders, Danièle; O'Dorchai, Sile Padraigin

    2008-01-01

    All over Europe, parental leaves are essentially taken by women which leads to perpetuate gender inequalities in the labour market. The economic literature illustrates the issues at stake and is presented in this article to contextualise the analysis of the Belgian parental leave system. The Belgian parental leave system has two strong features: it is individualised and it offers a relatively short leave. The system could be improved by the implementation of a wage-related payment. However, p...

  3. Leaving home in Denmark

    DEFF Research Database (Denmark)

    Nielsen, Rikke Skovgaard

    2015-01-01

    The paper focuses on ethnic differences in the timing and patterns of leaving the parental home. Leaving home is a key transition in the life course of the individual, and extensive research has been conducted on the timing and patterns of leaving it. However, ethnic differences in these patterns...

  4. 科尔沁沙地黄榆种子散布的空间差异及规律%Spatial difference and regularity of seed dispersal of Ulmus macrocarpa in Horqin Sandy Land, China

    Institute of Scientific and Technical Information of China (English)

    杨允菲; 白云鹏; 李建东

    2012-01-01

    黄榆(Ulmus macrocarpa)是典型的风播植物,在科尔沁沙地可以形成单一优势种林地.通过对其林下随机取样和林缘与孤立树不同方向从树基部向外的有序取样调查,分析了英榆林下和林缘外不同距离的种子沉降特征、林缘和孤立树种子散布方向的差异性与规律性.结果表明,黄榆平均种子密度以林下最大,林缘3m处已显著减小,林缘外随着距离增加黄榆平均种子密度呈指数减少态势,且越远越不均匀.林缘和孤立树不同方向在26m内,单位面积连续分布的种子累积数量均以顺风向频率大的东北方向最多,以逆风向频率大的西南或西方向最少.林缘和孤立树共10个方向的垂直断面从树基部向外的单位面积种子数量频度均符合Weibull分布和对数-正态分布密度函数(x2(a)<0.900),具有相同的种子散布格局.在科尔沁沙地自然条件下,黄榆在各方向具有相同的“远距离”种子散布机制.%Aims Ulmus macrocarpa is a typical anemochorous plant. It can form mono-dominant woodland in Keerqin Sandy Land, China. Our objectives were to investigate seed-fall characteristics of U. macrocarpa in the under-story and away from both the woodland edges and isolated trees at different distances in different compass directions, and to illustrate the underlying mechanisms of seed dispersal in U. macrocarpa. Methods In mid June 2011, we investigated seed dispersal after seeds fall in a nature reserve of U. macrocarpa woodland in Tongyu County in western Jilin Province. The woodland is about 50 km2 in area which has nearly primitive landscape appearance. The seed density of U. macrocarpa was randomly sampled in the understory and orderly sampled at 1 m intervals from the tree bases away from the woodland edges and isolated trees along vertical sections of different directions. The quadrat was 50 cm × 50 cm in area. Differences in the seed density among the understory and parallel sections of

  5. Variation of Oriental Oak (Quercus variabilis Leaf δ13C across Temperate and Subtropical China: Spatial Patterns and Sensitivity to Precipitation

    Directory of Open Access Journals (Sweden)

    Baoming Du

    2015-06-01

    Full Text Available The concentration of the carbon-13 isotope (leaf δ13C in leaves is negatively correlated with the mean annual precipitation (MAP atlarge geographical scales. In this paper, we explain the spatial pattern of leaf δ13C variation for deciduous oriental oak (Quercus variabilis Bl. across temperate and subtropical biomes and its sensitivity to climate factors such as MAP. There was a 6‰ variation in the leaf δ13C values of oak with a significant positive correlation with latitude and negative correlations with the mean annual temperature (MAT and MAP. There was no correlation between leaf δ13C and altitude or longitude. Stepwise multiple regression analyses showed that leaf δ13C decreased 0.3‰ per 100 mm increase in MAP. MAP alone could account for 68% of the observed variation in leaf δ13C. These results can be used to improve predictions for plant responses to climate change and particularly lower rainfall.

  6. [Aboveground architecture and biomass distribution of Quercus variabilis].

    Science.gov (United States)

    Yu, Bi-yun; Zhang, Wen-hui; Hu, Xiao-jing; Shen, Jia-peng; Zhen, Xue-yuan; Yang, Xiao-zhou

    2015-08-01

    The aboveground architecture, biomass and its allocation, and the relationship between architecture and biomass of Quercus variabilis of different diameter classes in Shangluo, south slope of Qinling Mountains were researched. The results showed that differences existed in the aboveground architecture and biomass allocation of Q. variabilis of different diameter classes. With the increase of diameter class, tree height, DBH, and crown width increased gradually. The average decline rate of each diameter class increased firstly then decreased. Q. variabilis overall bifurcation ratio and stepwise bifurcation ratio increased then declined. The specific leaf areas of Q. variabilis of all different diameter classes at vertical direction were 0.02-0.03, and the larger values of leaf mass ratio, LAI and leaf area ratio at vertical direction in diameter level I , II, III appeared in the middle and upper trunk, while in diameter level IV, V, VI, they appeared in the central trunk, with the increase of diameter class, there appeared two peaks in vertical direction, which located in the lower and upper trunk. The trunk biomass accounted for 71.8%-88.4% of Q. variabilis aboveground biomass, while the branch biomass accounted for 5.8%-19.6%, and the leaf biomass accounted for 4.2%-8.6%. With the increase of diameter class, stem biomass proportion of Q. variabilis decreased firstly then increased, while the branch and leaf biomass proportion showed a trend that increased at first then decreased, and then increased again. The aboveground biomass of Q. variabilis was significantly positively correlated to tree height, DBH, crown width and stepwise bifurcation ratio (R2:1), and positively related to the overall bifurcation ratio and stepwise bifurcation ratio (R3:2), but there was no significant correlation. Trunk biomass and total biomass aboveground were negatively related to the trunk decline rate, while branch biomass and leaf biomass were positively related to trunk decline

  7. Negative leave balances

    CERN Multimedia

    Human Resources Department

    2005-01-01

    Members of the personnel entitled to annual leave and, where appropriate, saved leave and/or compensatory leave are requested to take note of the new arrangements described below, which were recommended by the Standing Concertation Committee (SCC) at its meeting on 1Â September 2005 and subsequently approved by the Director-General. The changes do not apply to members of the personnel participating in the Progressive Retirement Programme (PRP) or the Part-time Work as a pre-retirement measure, for whom the specific provisions communicated at the time of joining will continue to apply. Â Negative balances in annual leave, saved leave and/or compensatory leave accounts at the end of the leave year (30th September) and on the date on which bonuses are credited to the saved leave account (31st December): Where members of the personnel have a leave account with a negative balance on 30Â September and/or 31Â December, leave will automatically be transferred from one account to another on the relevant dates i...

  8. Negative leave balances

    CERN Multimedia

    Human Resources Department

    2005-01-01

    Members of the personnel entitled to annual leave and, where appropriate, saved leave and/or compensatory leave are requested to take note of the new arrangements described below, which were recommended by the Standing Concertation Committee (SCC) at its meeting on 1 September 2005 and subsequently approved by the Director-General. The changes do not apply to members of the personnel participating in the Progressive Retirement Programme (PRP) or the Part-time Work as a pre-retirement measure, for whom the specific provisions communicated at the time of joining will continue to apply.  Negative balances in annual leave, saved leave and/or compensatory leave accounts at the end of the leave year (30th September) and on the date on which bonuses are credited to the saved leave account (31st December): Where members of the personnel have a leave account with a negative balance on 30 September and/or 31 December, leave will automatically be transferred from one account to another on the relevant dates in or...

  9. Preliminary Comparative Analysis of Phenological Varieties of Quercus robur by ISSR-Markers

    Directory of Open Access Journals (Sweden)

    Vasiliy Chokheli

    2016-01-01

    Full Text Available Quercus robur L. is a valuable wood species having long ontogeny and promising to create long-living artificial plantings of recreational and ameliorative purposes in the steppes zone of Russia and other countries. In this work we have performed the genotyping of varieties of Quercus robur L. obtained from collection of Botanical Garden of Southern Federal University using intersimple sequence repeat (ISSR molecular markers. The most polymorphic ISSR-marker (GA 8YC was found in the collection. The polymorphic DNA markers identified in the present study can be used for the future breeding works to obtain valuable genotypes of Quercus genus. In addition we have performed DNA fingerprinting of the prospective sample of the variety Q. robur var. tardiflora Czern.

  10. 40 CFR 180.1179 - Plant extract derived from Opuntia lindheimeri, Quercus falcata, Rhus aromatica, and Rhizophoria...

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Plant extract derived from Opuntia... Tolerances § 180.1179 Plant extract derived from Opuntia lindheimeri, Quercus falcata, Rhus aromatica, and... derived from Opuntia lindheimeri, Quercus falcata, Rhus aromatica, and Rhizophoria mangle is exempted...

  11. Low temperature during winter elicits differential responses among populations of the Mediterranean evergreen cork oak (Quercus suber).

    Science.gov (United States)

    Aranda, I; Castro, L; Alía, R; Pardos, J A; Gil, L

    2005-08-01

    Populations of cork oak (Quercus suber L.) were assessed for seasonal and inter-population variability in, and temperature responses of, the ratio between light-induced variable and maximum fluorescence of chlorophyll, Fv/Fm, considered a surrogate for the maximum photochemical efficiency of photosystem II (PSII). Seedlings from 10 populations throughout the distribution range of Q. suber in the Mediterranean basin were grown in a common garden in central Spain. The Fv/Fm ratio of dark-adapted leaves was measured at dawn every month for 2 years. Air temperature was recorded at a nearby climatic station. During the summer, when maximum air temperatures reached 40 degrees C, there were no significant differences in Fv/Fm among populations, but significant differences were seen during the winter. In colder months, Fv/Fm ranged in all populations between 0.5-0.6 and 0.2-0.3 in 2001 and 2002, respectively. The variance explained by the population effect was greatest during winter months, especially in 2002, reaching a peak value of 10% when minimum air temperature was below -10 degrees C. Populations originating from warmer sites showed the largest decline in Fv/Fm between the end of 2001 and the beginning of 2002. Thus, a negative linear relationship was established between mean annual temperature at the population source and population mean Fv/Fm recorded in the coldest month in 2002 and normalized by the Fv/Fm spring measurement.

  12. Differential Sensitivity of Macrocarpa and Microcarpa Types of Chickpea (Cicer arietinum L.) to Water Stress: Association of Contrasting Stress Response with Oxidative Injury

    Institute of Scientific and Technical Information of China (English)

    Harsh Nayyar; Smita Singh; Satwinder Kaur; Sanjeev Kumar; Hari D. Upadhyaya

    2006-01-01

    Chickpea (Cicer arietinum L.) is particularly sensitive to water stress at its reproductive phase and, under conditions of water stress, will abort flowers and pods, thus reducing yield potential. There are two types of chickpea: (i) Macrocarpa ("Kabuli"), which has large, rams head-shaped, light brown seeds; and (ii)Microcarpa ("Desi"), which has small, angular and dark-brown seeds. Relatively speaking, "Kabuli" has been reported to be more sensitive to water stress than "Desi". The underlying mechanisms associated with contrasting sensitivity to water stress at the metabolic level are not well understood. We hypothesized that one of the reasons for contrasting water stress sensitivity in the two types of chickpea may be a variation in oxidative injury. In the present study, plants of both types were water stressed at the reproductive stage for 14 d. As a result of the stress, the "Kabuli" type exhibited an 80% reduction in seed yield over control compared with a 64% reduction observed for the "Desi" type. The decrease in leaf water potential (Ψw) was faster in the "Kabuli" compared with the "Desi" type. At the end of the water stress period, Ψ was reduced to -2.9 and -3.1 MPa in the "Desi" and "Kabuli" types, respectively, without any significant difference between them. On the last day of stress, "Kabuli" experienced 20% more membrane injury than "Desi". The chlorophyll content and photosynthetic rate were significantly greater in "Desi"compared with "Kabuli". The malondialdehyde and H2O2 content were markedly higher at the end of the water stress in "Kabuli" compared with "Desi", indicating greater oxidative stress in the former. Levels of anti-oxidants, such as ascorbic acid and glutathione, were significantly higher in "Desi" than "Kabuli".Superoxide dismutase and catalase activity did not differ significantly between the two types of chickpea,whereas on the 10th day, the activities of ascorbate peroxidase, dehydroascorbate reductase, and glutathione

  13. Polyphenol Compounds of Mahkota Dewa (Phaleria macrocarpa[Scheff.] Boerl Up-regulated Caspase-3 and Apoptosis Index in Balb/c Strain Mice

    Directory of Open Access Journals (Sweden)

    Indranila KS

    2016-04-01

    Full Text Available Background: Polyphenol compounds of Mahkota Dewa (Phaleria macrocarpa[Scheff.] Boerl (PMD can potentially be used as ant cancer treatment by scavanging radical molecules. The effect in vivois still limited to Indonesia. Purpose: This research was aimed to validate the activity of PMD in increasingcaspase-3 expression and apoptosis in Balb/c mice, induced by Benzo(apyrene (BaP. Methods: A posttest control group was implemented and used by 40 Balb/c mice at the age of 1-2 weeks, with the body weight of 20-30 g. The tumor induction was administered to the mice using BaP. The animals were randomized into two groups called the control group and the PMD treatment group, the latter of which was given a dosage of 50mg. Lung tumor growth was assessed through surgery at week 8, 17, and 26. The results of caspase-3expression and apoptotic index from IHC-TUNEL staining were analyzed using Kruskal-Wallis, Mann-Whitney, One-way ANOVA, and Post hoc test LSD with significant levels of p<α (0,05.This research was approved by Ethical Clearance. Results: Oral administration of 50mg PMD significantly increased caspase-3 expression and apoptotic index in the treatment group animals at weeks 8, 17, and 26. Carcinogenesis incidence in the control group were respectively found at2,32±0,26 and 3,93±0,46 at weeks 8 and 26, while those of the treatment group were 1,88±0,38 and 0,88±0,22 (p=0,001. The apoptotic index in the control group was0,00±0,00 at 8 weeksand0,92+0,22at 26 weeks, whereas the indexes of the treatment group were 1,12±0,71 and 2,02±1,05 (p=0,001. In the control group, the caspase-3 expression at weeks 8 and 26 were 0,28±0,17 and 0,56±0,16, while those in the treatment group were 0,60±0,14 at week 8 and 2,52±0,33 at week 26 (p=0,001. Conclusion: The treatment of PMD effectively induced cell apoptosis in the Balb/c mice via up- regulation of the caspase-3 expression, thereby increasing the apoptotic index. This shows that PMD has anticancer

  14. PITYOPHAGUS QUERCUS REITTER, 1877, A NEW SAPROXYLIC SAP BEETLE FOR THE ITALIAN FAUNA (Coleoptera, Nitidulidae

    Directory of Open Access Journals (Sweden)

    Paolo Audisio

    2011-10-01

    Full Text Available During ecological investigations on saproxylic beetle communities of central Italy (Latium, at Bosco Polverino (a mixed evergreen/deciduous forest fragment dominated by cork oaks, and at Allumiere (a small fragment of beech forest surrounded by turkey oak stands, the authors found three specimens of Pityophagus quercus Reitter, 1877 (Coleoptera, Nitidulidae. These are the first known records of this species in Italy, and the first one in association with an evergreen oak, Quercus suber. This discovery led us to review both bionomical and faunistic data so far available on this exceedingly rare and poorly known species.

  15. How drought severity constrains gross primary production(GPP) and its partitioning among carbon pools in a Quercus ilex coppice?

    Science.gov (United States)

    Rambal, S.; Lempereur, M.; Limousin, J. M.; Martin-StPaul, N. K.; Ourcival, J. M.; Rodríguez-Calcerrada, J.

    2014-12-01

    The partitioning of photosynthates toward biomass compartments plays a crucial role in the carbon (C) sink function of forests. Few studies have examined how carbon is allocated toward plant compartments in drought-prone forests. We analyzed the fate of gross primary production (GPP) in relation to yearly water deficit in an old evergreen Mediterranean Quercus ilex coppice severely affected by water limitations. Carbon fluxes between the ecosystem and the atmosphere were measured with an eddy covariance flux tower running continuously since 2001. Discrete measurements of litterfall, stem growth and fAPAR allowed us to derive annual productions of leaves, wood, flowers and acorns, and an isometric relationship between stem and belowground biomass has been used to estimate perennial belowground growth. By combining eddy covariance fluxes with annual net primary productions (NPP), we managed to close a C budget and derive values of autotrophic, heterotrophic respirations and carbon-use efficiency (CUE; the ratio between NPP and GPP). Average values of yearly net ecosystem production (NEP), GPP and Reco were 282, 1259 and 977 g C m-2. The corresponding aboveground net primary production (ANPP) components were 142.5, 26.4 and 69.6 g C m-2 for leaves, reproductive effort (flowers and fruits) and stems, respectively. NEP, GPP and Reco were affected by annual water deficit. Partitioning to the different plant compartments was also impacted by drought, with a hierarchy of responses going from the most affected - the stem growth - to the least affected - the leaf production. The average CUE was 0.40, which is well in the range for Mediterranean-type forest ecosystems. CUE tended to decrease less drastically in response to drought than GPP and NPP did, probably due to drought acclimation of autotrophic respiration. Overall, our results provide a baseline for modeling the inter-annual variations of carbon fluxes and allocation in this widespread Mediterranean ecosystem, and

  16. Comparative photochemical and phenomorphological responses to winter stress of an evergreen ( Quercus ilex L.) and a semi-deciduous ( Cistus albidus L.) Mediterranean woody species

    Science.gov (United States)

    Oliveira, Graça; Peñuelas, Josep

    2000-03-01

    The impact of winter stress on plants from a Mediterranean area was evaluated through comparison of photosystem II (PS II) efficiencies and phenomorphological characteristics of two Mediterranean woody species - Quercus ilex (evergreen) and Cistus albidus (semi-deciduous). The studies were carried out in NE Spain, at two sites with different mean winter temperatures. The results showed that reductions of the efficiency of PS II may occur in Mediterranean plant communities during winter, and are especially remarkable on colder days. The extent and duration of the decrease in PS II efficiency (photoinhibition) depended not only on the climatic conditions, but also on the site, on the species considered and on the position of leaves in the plant canopy. Increased photoinhibition at the colder site was only clear for C. albidus. Nevertheless, the efficiencies of PS II were always higher in C. albidus than in Q. ilex. Phenological patterns, morphology and leaf inclination may protect C. albidus leaves from potentially photoinhibitory conditions in winter. Morphological and structural photoprotection is apparently not so well developed in Q. ilex, which probably relies more on increased protection at the photochemical level of its long-lived leaves. As has been reported in relation to summer-drought stress, Q. ilex has possibly developed a strategy of tolerance to photoinhibition, whereas C. albidus relies preferentially on avoidance features.

  17. The Temporary Leave Dilemma -

    DEFF Research Database (Denmark)

    Amilon, Anna

    2010-01-01

    Lone mothers have to take care of a sick child with little or no help from the child’s other parent and have to carry all costs connected to leave-taking. This paper empirically tests whether lone mothers take more temporary parental leave to care for sick children than partnered mothers and whet......Lone mothers have to take care of a sick child with little or no help from the child’s other parent and have to carry all costs connected to leave-taking. This paper empirically tests whether lone mothers take more temporary parental leave to care for sick children than partnered mothers...

  18. Modeling of stomatal conductance to estimate stomatal ozone uptake by Fagus crenata, Quercus serrata, Quercus mongolica var. crispula and Betula platyphylla.

    Science.gov (United States)

    Kinose, Yoshiyuki; Azuchi, Fumika; Uehara, Yui; Kanomata, Tomoaki; Kobayashi, Ayumi; Yamaguchi, Masahiro; Izuta, Takeshi

    2014-11-01

    To construct stomatal conductance models and estimate stomatal O3 uptake for Fagus crenata, Quercus serrata, Quercus mongolica var. crispula and Betula platyphylla, stomatal conductance (gs) was measured in seedlings of the four tree species. Better estimates of gs were made by incorporating the acute effects of O3 on gs into the models and the models could explain 34-52% of the variability in gs. Although the O3 concentration was relatively high in spring from April to May, COU of F. crenata, Q. serrata and Q. mongolica var. crispula were relatively low and the ratios of COU in spring to total COU in one year were 16.8% in all tree species because of low gs limited mainly by leaf pre-maturation and/or low temperature. The COU of B. platyphylla were relatively high mainly because of rapid leaf maturation and lower optimal temperature for stomatal opening.

  19. Warming and drought differentially influence the production and resorption of elemental and metabolic nitrogen pools in Quercus rubra.

    Science.gov (United States)

    Suseela, Vidya; Tharayil, Nishanth; Xing, Baoshan; Dukes, Jeffrey S

    2015-11-01

    The process of nutrient retranslocation from plant leaves during senescence subsequently affects both plant growth and soil nutrient cycling; changes in either of these could potentially feed back to climate change. Although elemental nutrient resorption has been shown to respond modestly to temperature and precipitation, we know remarkably little about the influence of increasing intensities of drought and warming on the resorption of different classes of plant metabolites. We studied the effect of warming and altered precipitation on the production and resorption of metabolites in Quercus rubra. The combination of warming and drought produced a higher abundance of compounds that can help to mitigate climatic stress by functioning as osmoregulators and antioxidants, including important intermediaries of the tricarboxylic acid (TCA) cycle, amino acids including proline and citrulline, and polyamines such as putrescine. Resorption efficiencies (REs) of extractable metabolites surprisingly had opposite responses to drought and warming; drought treatments generally increased RE of metabolites compared to ambient and wet treatments, while warming decreased RE. However, RE of total N differed markedly from that of extractable metabolites such as amino acids; for instance, droughted plants resorbed a smaller fraction of elemental N from their leaves than plants exposed to the ambient control. In contrast, plants in drought treatment resorbed amino acids more efficiently (>90%) than those in ambient (65-77%) or wet (42-58%) treatments. Across the climate treatments, the RE of elemental N correlated negatively with tissue tannin concentration, indicating that polyphenols produced in leaves under climatic stress could interfere with N resorption. Thus, senesced leaves from drier conditions might have a lower nutritive value to soil heterotrophs during the initial stages of litter decomposition despite a higher elemental N content of these tissues. Our results suggest that N

  20. Growth cessation uncouples isotopic signals in leaves and tree rings of drought-exposed oak trees.

    Science.gov (United States)

    Pflug, Ellen E; Siegwolf, R; Buchmann, N; Dobbertin, M; Kuster, T M; Günthardt-Goerg, M S; Arend, M

    2015-10-01

    An increase in temperature along with a decrease in summer precipitation in Central Europe will result in an increased frequency of drought events and gradually lead to a change in species composition in forest ecosystems. In the present study, young oaks (Quercus robur L. and Quercus petraea (Matt.) Liebl.) were transplanted into large mesocosms and exposed for 3 years to experimental warming and a drought treatment with yearly increasing intensities. Carbon and oxygen isotopic (δ(13)C and δ(18)O) patterns were analysed in leaf tissue and tree-ring cellulose and linked to leaf physiological measures and tree-ring growth. Warming had no effect on the isotopic patterns in leaves and tree rings, while drought increased δ(18)O and δ(13)C. Under severe drought, an unexpected isotopic pattern, with a decrease in δ(18)O, was observed in tree rings but not in leaves. This decrease in δ(18)O could not be explained by concurrent physiological analyses and is not supported by current physiological knowledge. Analysis of intra-annual tree-ring growth revealed a drought-induced growth cessation that interfered with the record of isotopic signals imprinted on recently formed leaf carbohydrates. This missing record indicates isotopic uncoupling of leaves and tree rings, which may have serious implications for the interpretation of tree-ring isotopes, particularly from trees that experienced growth-limiting stresses.

  1. Paleoatmospheric signatures in Neogene fossil leaves; Utrecht University, Utrecht (Netherlands). Lab. of Paleobotany and Palynology

    Energy Technology Data Exchange (ETDEWEB)

    Burgh, J. van der; Visscher, H.; Dilcher, D.L.; Kuerschner, W.M.

    1993-06-18

    An increase in the atmospheric carbon dioxide (CO[sub 2]) concentration results in a decrease in the number of leaf stomata. This relation is known both from historical observations of vegetation over the past 200 years and from experimental manipulations of microenvironments. Evidence from stomatal frequencies of fossil [ital Quercus petraea] leaves indicates that this relation can be applied as a bioindicator for changes in paleoatmospheric CO[sub 2] concentrations during the last 10 million years. The data suggest that late Neogene CO[sub 2] concentrations fluctuated between about 280 and 370 parts per million by volume. 20 refs., 3 figs.

  2. Xylem dysfunction in Quercus: vessel sizes, tyloses, cavitation and seasonal changes in embolism.

    Science.gov (United States)

    Cochard, H; Tyree, M T

    1990-12-01

    The seasonal progression of xylem dysfunction from tyloses and embolism induced both by cavitation and frost was studied in Quercus rubra L. and Quercus alba L. branches. Vessel lengths and diameters were measured in current-year rings of branches of various ages. Vessels in current-year shoots are about the same size as those in many diffuse porous trees, but vessels in older branches are two to six times larger in diameter and typically more than 10 times longer. Large Quercus vessels were more vulnerable to cavitation than small vessels. The small vessels in current-year shoots were more vulnerable to cavitation than vessels of comparable size in diffuse porous species. Earlywood vessels are completely blocked by tyloses within a year of their formation. Tylose growth starts in winter, but the vessels are not fully blocked until the next summer. Many latewood vessels, by contrast, remain free of complete blockage for several years. In Q. rubra, loss of hydraulic conductivity in current-year shoots due to cavitation reaches 20% by August and > 90% after the first hard frost. Both laboratory and field observations confirm that the role of frost in causing loss of hydraulic conduction by embolism is much more dramatic in Quercus than in conifers and diffuse porous hardwoods.

  3. Intraspecific Phenotypic Variation and Ecological Genetics of Blue Oak (Quercus douglasii Hook. & Am.)

    Science.gov (United States)

    Kevin J. Rice; Doria R. Gordon; Jeanine L. Hardison; Jeffrey M. Welker

    1991-01-01

    A field experiment was conducted to examine the effects of soil water availability on blue oak (Quercus douglasii) seedling establishment. Acorns were planted either into cleared plots of 0, 10, 20, or 40 cm diameter. The cleared plots were located in two grazed and one ungrazed site. Half of the plots received drip irrigation in a split plot design...

  4. The effect of seed size variation in Quercus pacifica on seedling establishment and growth

    Science.gov (United States)

    Mario B. Pesendorfer

    2015-01-01

    Quercus pacifica, the island scrub-oak, is the dominant species in oak chaparral on the three largest California Channel Islands. While the population on Santa Cruz Island has experienced a strong recovery, the populations on Santa Rosa and Santa Catalina islands are of conservation concern, and managers are actively restoring oak habitat by...

  5. A bibliography for Quercus garryana and other geographically associated and botanically related oaks.

    Science.gov (United States)

    Constance A. Harrington; Melanie A. Kallas

    2002-01-01

    Interest in Quercus garryana Dougl. ex Hook., commonly known as Oregon white oak or Garry oak, has increased in recent years as scientists, resource managers, and the general public focus attention on a forest type in decline. To aid those interested in learning what has previously been reported on this species, we have compiled a comprehensive bibliography for Q....

  6. Estudio taxonómico de cuatro especies de encino (Quercus) descritas por Warburg

    OpenAIRE

    1995-01-01

    Se determinaron como sinónimos de Quercus hintonii Warb. a Q. apiophylla Warb., Q. ochroestes Warb. y Q. sagata Warb., con base en el análisis de las descripciones originales, fototipos y ejemplares existentes en los herbarios. Además se realizaron observaciones de las poblaciones y colectas de ejemplares en las localidades tipo.

  7. Indicator values for lichens on Quercus as a tool to monitor ammonia pollution in Denmark

    DEFF Research Database (Denmark)

    Berthelsen, K.; Olsen, H. B.; Søchting, Ulrik

    2008-01-01

    The epiphytic lichen vegetation on solitary Quercus trees was investigated on 13 locations in Denmark in order to test the usability of indicator values to quantify ammonia deposition from the ambient air. Indicator values calculated for each location corresponded well with the expected ecological...

  8. Concentric Ring Method for generating pollen maps. Quercus as case study.

    Science.gov (United States)

    Oteros, Jose; Valencia, Rosa Mª; Del Río, Sara; Vega, Ana Mª; García-Mozo, Herminia; Galán, Carmen; Gutiérrez, Pablo; Mandrioli, Paolo; Fernández-González, Delia

    2017-01-15

    Mapping pollen concentrations is of great interest to study the health impact and ecological implications or for forestry or agronomical purposes. A deep knowledge about factors affecting airborne pollen is essential for predicting and understanding its dynamics. The present work sought to predict annual Quercus pollen over the Castilla and León region (Central and Northern Spain). Also to understand the relationship between airborne pollen and landscape. Records of Quercus and Quercus pyrenaica pollen types were collected at 13 monitoring sites over a period of 8years. They were analyzed together with land use data applying the Concentric Ring Method (CRM), a technique that we developed to study the relationship between airborne particle concentrations and emission sources in the region. The maximum correlation between the Quercus pollen and forms of vegetation was determined by shrubland and "dehesa" areas. For the specific Qi pyrenaica model (Q. pyrenaica pollen and Q. pyrenaica forest distribution), the maximum influence of emission sources on airborne pollen was observed at 14km from the pollen trap location with some positive correlations up to a distance of 43km. Apart from meteorological behavior, the local features of the region can explain pollen dispersion patterns. The method that we develop here proved to be a powerful tool for multi-source pollen mapping based on land use. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Predicting the height growth of oak species (Quercus) reproduction over a 23-year period following clearcutting

    Science.gov (United States)

    J. Travis Swaim; Daniel C. Dey; Michael R. Saunders; Dale R. Weigel; Christopher D. Thornton; John M. Kabrick; Michael A. Jenkins

    2016-01-01

    We resampled plots from a repeated measures study implemented on the Hoosier National Forest (HNF) in southern Indiana in 1988 to investigate the influence of site and seedling physical attributes on height growth and establishment success of oak species (Quercus spp.) reproduction in stands regenerated by the clearcut method. Before harvest, an...

  10. Epiphytic bryophytes of Quercus forests in Central and North inland Iberian Peninsula

    Directory of Open Access Journals (Sweden)

    Nagore García Medina

    2015-04-01

    Full Text Available Diversity patterns are governed by a complex network of interacting factors. Studies directed to disentangle the most important factors affecting diversity have frequently shown divergent results, which has encouraged a rewarding debate about the relative importance of each factor. Scale dependency has been identified as a direct cause of at least part of such divergences. However, studies with spatially-explicit measurements at different scales are costly and therefore they are relatively scarce despite their importance. Here, we present a database to disentangle the cross-scale variation in the importance of factors affecting the diversity of epiphytic bryophyte communities in Quercus dominated forests (Quercus ilex L., Quercus pyrenaica Willd. and Quercus faginea Lam. in the North-western region of the Iberian Peninsula. We provide species-per-site abundance information with more than 9000 entries and an environmental table containing 20 in situ measured variables at three different scales (forest, stand, and sample. The database will help to advance the research of cross-scale effects of diversity patterns while at the same time providing valuable information on the distribution of a poorly known group of organisms. 

  11. Utility of ITS sequence data for phylogenetic reconstruction of Italian Quercus spp.

    Science.gov (United States)

    Bellarosa, Rosanna; Simeone, Marco C; Papini, Alessio; Schirone, Bartolomeo

    2005-02-01

    Nuclear ribosomal DNA sequences encoding the 5.8S RNA and the flanking internal transcribed spacers (ITS1 and ITS2) were used to test the phylogenetic relationships within 12 Italian Quercus taxa (Fagaceae). Hypotheses of sequence orthology are tested by detailed inspection of some basic features of oak ITS sequences (i.e., general patterns of conserved domains, thermodynamic stability and predicted conformation of the secondary structure of transcripts) that also allowed more accurate sequence alignment. Analysis of ITS variation supported three monophyletic groups, corresponding to subg. Cerris, Schlerophyllodrys (=Ilex group sensu Nixon) and Quercus, as proposed by Schwarz [Feddes Rep., Sonderbeih. D, 1-200]. A derivation of the "Cerris group" from the "Ilex group" is suggested, with Q. cerris sister to the rest of the "Cerris group." Quercus pubescens was found to be sister to the rest of the "Quercus group." The status of hybrispecies of Q. crenata (Q. cerrisxQ. suber) and Q. morisii (Q. ilexxQ. suber) was evaluated and discussed. Finally, the phylogenetic position of the Italian species in a broader context of the genus is presented. The utility of the ITS marker to assess the molecular systematics of oaks is therefore confirmed. The importance of Italy as a region with a high degree of diversity at the population and genetic level is discussed.

  12. Maternal influences on seed mass effect and initial seedling growth in four Quercus species

    Science.gov (United States)

    González-Rodríguez, Victoria; Villar, Rafael; Navarro-Cerrillo, Rafael M.

    2011-01-01

    Seed mass represents the reserves available for growth in the first stages of plant establishment. Variation in seed mass is an important trait which may have consequences for growth and survival of seedlings. Three mechanisms have been proposed to explain how seed mass influences seedling development: the reserve use effect, the metabolic effect and the seedling-size effect. Few studies have evaluated at the same time the three hypotheses within species and none have evaluated the effect of the mother trees. We studied four Quercus species by selecting five mother trees per species. Seeds were sown in a glasshouse and the use of seed reserves, seedling growth and morphology were measured. Considering all mothers of the same species together, we did not find the reserve effect for any species, the metabolic effect was observed in all species except for Quercus suber, and the seedling-size effect was matched for all the species. Within species, maternal origin modified the studied relationships and thus the studied mechanisms as we did not observe seed mass effects on all mothers from each species. Moreover, the metabolic effect was not found in any mother of Quercus ilex and Quercus faginea. We concluded that a maternal effect can change seed mass relationships with traits related to seedling establishment. The conservation of this high intra-specific variability must be considered to guarantee species performance in heterogeneous environments and in particular in the current context of climate change.

  13. Indicator values for lichens on Quercus as a tool to monitor ammonia pollution in Denmark

    DEFF Research Database (Denmark)

    Berthelsen, K.; Olsen, H. B.; Søchting, Ulrik

    2008-01-01

    The epiphytic lichen vegetation on solitary Quercus trees was investigated on 13 locations in Denmark in order to test the usability of indicator values to quantify ammonia deposition from the ambient air. Indicator values calculated for each location corresponded well with the expected ecological...... as a tool for quantitative estimation of ammonia deposition in relation to sensitive Danish ecosystems.  ...

  14. Chemical composition of the essential oils of the berries of Juniperus oxycedrus L. ssp. rufescens (L. K.) and Juniperus oxycedrus L. ssp. macrocarpa (S. & m.) Ball. and their antioxidant activities.

    Science.gov (United States)

    Hanène, Medini; Ameur, Elaissi; Larbi, Khouja Med; Piras, Alessandra; Porcedda, Silvia; Falconieri, Danilo; Marongiu, Bruno; Farhat, Farhat; Chemli, Rachid

    2012-01-01

    This study is outlined to probe the chemical composition of essential oil and in vitro antioxidant activity of Juniperus oxycedrus ssp. macrocarpa (S. & m.) Ball. and Juniperus oxycedrus L. ssp. rufescens (L. K.) berries, collected from four sites, according to their maturity phase. The chemical composition of the hydrodistilled essential oil was analysed by GC-MS. Forty-eight compounds were identified, accounting for approximately 79.8-98.9% of the oil. The main constituents were α-pinene, germacrene D, myrcene, abietadiene and cis-calamenene, their mean percentage vary according to their phenological stage. The antioxidant activity of the samples was determined by the ABTS and DPPH radical scavenging activities. Hawaria essential oil extracted from mature berries showed the highest antioxidant capacity.

  15. Studies on planting trees in a smoke-polluted area. On the actual state of damage of trees due to air pollution in Iwaki area. [Quercus serrata; Pinus densiflora

    Energy Technology Data Exchange (ETDEWEB)

    1974-12-01

    Damage to trees in the Iwaki area, ranging from slight growth suppression to changes in leaf color, leaf-fall, and withering, was examined in relation to industrial sulfur oxide emissions. A survey of local conditions, amount of tree growth, index of damage, and the sulfur content of leaves from each of 20 pine trees (Pinus densiflora) 10 to 20 yr old was performed. There was a positive logarithmic relationship between the elongation of new twigs and the distance from the smoke source. Generally, the vigor of trees was higher, the greater the distance from the smoke source, with some exceptions suggesting the effect of topography. Sulfur content showed the same inverse tendency with some exceptions, and it was lower than that determined previously. The sulfur content of leaves of Quercus serrata was one and a half to two times greater than that of P. densiflora.

  16. Icephobicity of Leaves

    Science.gov (United States)

    Kavehpour, H. Pirouz; Shirazi, Elika T.; Alizadeh-Birjandi, Elaheh

    2016-11-01

    Ice adhesion and excessive accumulation on exposed structures and equipment are well known to cause serious problems in cold-climate regions; therefore, the development of coatings that can resist icing can solve many challenges in various areas of industry. This work was inspired by nature and ice-resistivity and superhydrophobicity of plants leaves. Kale is an example of a plant that can be harvested in winter. It shows superhydrophobic behavior, which is normally known as an advantage for cleaning the leaves, but we were able to show that its surface structure and high contact angle of water drops on kale leaves could delay the ice formation process making it a good candidate for an ice-repellent coating. We have performed in-depth experimental analyses on how different plants can prevent icing, and contact angle measurements and scanning electron microscopy (SEM) of the leaves were taken to further mimic their surface morphology.

  17. Maternity Leave Policies

    Science.gov (United States)

    Strang, Lucy; Broeks, Miriam

    2017-01-01

    Abstract Over recent years many European Union countries have made changes to the design of the maternity leave provision. These policy developments reflect calls for greater gender equality in the workforce and more equal share of childcare responsibilities. However, while research shows that long period of leave can have negative effects on women's labour market attachment and career advancements, early return to work can be seen as a factor preventing exclusive breastfeeding, and therefore, potentially having negative health impacts for babies. Indeed, the World Health Organisation recommends exclusive breastfeeding up to 6 months of age to provide babies with the nutrition for healthy growth and brain development, protection from life-threatening ailments, obesity and non-communicable diseases such as asthma and diabetes. Therefore, labour market demands on women may be at odds with the health benefits for children gained by longer periods of maternity leave. The aim of this article is to examine the relationship between leave provision and health benefits for children. We examine maternity and parental leave provision across European countries and its potential impact on the breastfeeding of very young babies (up to 6-months of age). We also consider economic factors of potential extension of maternity leave provision to 6 months, such as costs to businesses, effects on the female labour market attachment, and wider consequences (benefits and costs) for individuals, families, employers and the wider society. PMID:28983432

  18. [Duration of maternity leave and sick leave during pregnancy].

    Science.gov (United States)

    Tophøj, A; Sabroe, S

    1999-09-06

    The aim of the project was to describe the reasons for sick leave during pregnancy. This article presents data on a subgroup of women on sick leave. The purpose of this reanalysis was to examine whether women with short maternity leave had longer sick leave during pregnancy. Pregnant women in a Danish County applying for sick leave in a year were consecutively included in the study. Data were obtained by questionnaires during 1991-1992. Women with rights to a longer maternity leave, obtained through collective bargaining, were mainly employed in occupational groups related to the public sector and were on sick leave significantly longer, than women with short maternity leave, obtained only through legislation. The diagnoses differed among the two groups. Data suggest unequal possibilities for obtaining pregnancy related sick leave, as women with longer predelivery leave and a more secure employment situation had significantly longer sick leave than other women.

  19. Summer season and long-term drought increase the richness of bacteria and fungi in the foliar phyllosphere of Quercus ilex in a mixed Mediterranean forest.

    Science.gov (United States)

    Peñuelas, J; Rico, L; Ogaya, R; Jump, A S; Terradas, J

    2012-07-01

    We explored the changes in richness, diversity and evenness of epiphytic (on the leaf surface) and endophytic (within leaf tissues) bacteria and fungi in the foliar phyllosphere of Quercus ilex, the dominant tree species of Mediterranean forests. Bacteria and fungi were assessed during ontogenic development of the leaves, from the wet spring to the dry summer season in control plots and in plots subjected to drought conditions mimicking those projected for future decades. Our aim was to monitor succession in microbiota during the colonisation of plant leaves and its response to climate change. Ontogeny and seasonality exerted a strong influence on richness and diversity of the microbial phyllosphere community, which decreased in summer in the whole leaf and increased in summer in the epiphytic phyllosphere. Drought precluded the decrease in whole leaf phyllosphere diversity and increased the rise in the epiphytic phyllosphere. Both whole leaf bacterial and fungal richness decreased with the decrease in physiological activity and productivity of the summer season in control trees. As expected, the richness of epiphytic bacteria and fungi increased in summer after increasing time of colonisation. Under summer dry conditions, there was a positive relationship between TRF (terminal restriction fragments) richness and drought, both for whole leaf and epiphytic phyllosphere, and especially for fungal communities. These results demonstrate that changes in climate are likely to significantly alter microbial abundance and composition of the phyllosphere. Given the diverse functions and large number of phyllospheric microbes, the potential functional implications of such community shifts warrant exploration.

  20. Estudio morfométrico de Quercus sartorii y Q. xalapensis (Fagaceae Morphometric study of Quercus sartorii and Q. xalapensis (Fagaceae

    Directory of Open Access Journals (Sweden)

    Dorismilda Martínez-Cabrera

    2011-06-01

    Full Text Available Se realizó un estudio morfométrico con la finalidad de contribuir en la delimitación taxonómica de Quercus sartorii y Q. xalapensis. Para ello, se revisó material de herbario y se recolectó material en 11 poblaciones distribuidas en los estados de Hidalgo, San Luis Potosí, Tamaulipas y Veracruz, en México, incluyendo 2 poblaciones simpátricas. Los resultados del análisis de componentes principales y discriminante mostraron que los caracteres que contribuyeron a agrupar los individuos en su respectiva especie son los relacionados con el tamaño del fruto, en particular el diámetro de la bellota, de la nuez y de la cúpula. La bellota de Q. sartorii es de menor tamaño que la de Q. xalapensis. La variación detectada no se atribuyó a la latitud o altitud. El fenograma mostró la separación de 2 grupos que corresponden a los individuos de las 2 especies estudiadas, si los caracteres del fruto son incluidos. Además, de los caracteres cuantitativos ya mencionados, 3 del patrón de venación y 2 anatómicos contribuyeron a reconocer los individuos de cada especie. Estas diferencias se mantuvieron en los individuos de las poblaciones simpátricas, por lo que los resultados apoyaron la distinción de Quercus sartorii y Q. xalapensis.A morphometric study was carried out in order to evaluate morphological variation of Quercus sartorii and Q. xalapensis and to contribute to their taxonomic delimitation. Herbarium specimens and material of 11 populations from Mexico in the states of Hidalgo, San Luis Potosí, Tamaulipas, and Veracruz, including 2 sympatric populations, were studied. Characters from foliar architecture, fruits and anatomical features of periderm and wood were analyzed through multivariate and phenetic methods. Principal component and discriminant analyses showed that fruit characters such as acorn, nut, and cupule diameters contributed to group individuals in their species, the acorn of Q. sartorii being smaller than that of Q

  1. Mercury Distribution and Seasonal and Inter annual Variation of Mercury in Oak (Quercus ilex L.) in Almadenejos (Ciudad Real, Spain); Distribucion y Variacion Estacional e Interanual de Mercurio en La Encina (Quercus ilex L.) en el Municipio de Almadenejos (Ciudad Real)

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez-Alonso, J.; Sierra, M. J.; Millan, R.

    2014-10-01

    Plants that are exposed to environmental pollutants are able to accumulate them in their organs depending on plant species, type of organ or age among others. Evergreen plants can hold stems and leaves of the different age over the same branch. Thus, the amount of contaminants of these former organs could vary with its age because the contamination exposure time is different. The aim of this study is to know in a tree species, the mercury (Hg) distribution in it and the variation of Hg concentration in leaves and stems between consecutive years and along the same year. In order to carry this objective out, three different trees of Quercus ilex L. were selected and two branches were taken from each of them. Such trees are located in Almadenejos, a village from the Almaden mining district (Ciudad Real, Spain), an area well known due to the developed Hg mining activities for centuries. Considering each branch and each year, on average the results show that leaves had higher Hg concentration than stems. Furthermore, the lowest Hg concentration was measured in fruit (acorn). With regard to ageing effect on Hg concentration and taking into account each branch separately, the results show that the older leaves had higher Hg concentration than younger ones. Nevertheless, the oldest stems had not always higher Hg concentration than youngest ones. A seasonal variation in Hg content appeared both in leaves and in stems in 2010, increasing in 6.2 times on average, in about six months. This result suggests that this kind of organs should be analyzed in winter months. Finally, the results show a very high positive correlation between the Hg of the bark and the Hg of the wood in the sampled branches. Such result suggests that if bark is sampled and its Hg content is analyzed, we could know the Hg content in the big branches or in the trunk, avoiding the cutting of the branches or the whole tree. (Author)

  2. Specific polyphenols and tannins are associated with defense against insect herbivores in the tropical oak Quercus oleoides.

    Science.gov (United States)

    Moctezuma, Coral; Hammerbacher, Almuth; Heil, Martin; Gershenzon, Jonathan; Méndez-Alonzo, Rodrigo; Oyama, Ken

    2014-05-01

    The role of plant polyphenols as defenses against insect herbivores is controversial. We combined correlative field studies across three geographic regions (Northern Mexico, Southern Mexico, and Costa Rica) with induction experiments under controlled conditions to search for candidate compounds that might play a defensive role in the foliage of the tropical oak, Quercus oleoides. We quantified leaf damage caused by four herbivore guilds (chewers, skeletonizers, leaf miners, and gall forming insects) and analyzed the content of 18 polyphenols (including hydrolyzable tannins, flavan-3-ols, and flavonol glycosides) in the same set of leaves using high performance liquid chromatography and mass spectrometry. Foliar damage ranged from two to eight percent per region, and nearly 90% of all the damage was caused by chewing herbivores. Damage due to chewing herbivores was positively correlated with acutissimin B, catechin, and catechin dimer, and damage by mining herbivores was positively correlated with mongolinin A. By contrast, gall presence was negatively correlated with vescalagin and acutissimin B. By using redundancy analysis, we searched for the combinations of polyphenols that were associated to natural herbivory: the combination of mongolinin A and acutissimin B had the highest association to herbivory. In a common garden experiment with oak saplings, artificial damage increased the content of acutissimin B, mongolinin A, and vescalagin, whereas the content of catechin decreased. Specific polyphenols, either individually or in combination, rather than total polyphenols, were associated with standing leaf damage in this tropical oak. Future studies aimed at understanding the ecological role of polyphenols can use similar correlative studies to identify candidate compounds that could be used individually and in biologically meaningful combinations in tests with herbivores and pathogens.

  3. Investigation Of The Color Changing Properties Of Wood Stain Derived From Pinar Leaves

    Directory of Open Access Journals (Sweden)

    Abdi Atılgan

    2011-11-01

    Full Text Available This study was designed to develop an environmentally friendly wood stain derived pinar (Quercus aucheri leaves and determine the color stability of this stain when exposed to UV light irradiation. Wood stains derived from pinar leaves were prepared from aqueous solution with %3 iron (FeSO4.7H2O , % 5 alum ((KAl(SO42.12H2O, and % 10 vinegar mordant mixtures. Scots pine (Pinus sylvestris L., Turkish oriental beech (Fagus orientalis Lipsky and oak (Quercus petraea L. wood specimens were used as staining substrates. After treatment with the stain, the wood panels were exposed to UV light irradiation for periods of 100, 200, and 300 hours and determinated the total color changes was according to ISO 2470 standards. Results showed that wood stain derived from pinar extract provided some color stability after UV irradiation. According to results, Scots pine specimens treated with the pinar extract + iron mixture provided the smallest total color changes. Meanwhile the highest total color change provided on the Scots pine treated with pinar extract+alum mixture.

  4. Pattern recognition of acorns from different Quercus species based on oil content and fatty acid profile

    Directory of Open Access Journals (Sweden)

    Abreu, José M.F.

    2003-12-01

    Full Text Available The aim of this study was (i to characterize different species of Quercus genus and (ii to discriminate among them on the basis of the content and fatty acid composition of the oil in their fruits and/or their morphological aspects via pattern recognition techniques (Principal Component Analysis, PCA, Cluster Analysis, CA, and Discriminant Analysis, DA. Quercus rotundifolia Lam., Quercus suber L. and Quercus pyrenaica Willd., grown in the same stand in the centre of Portugal, were investigated. When oil content and respective fatty acid composition were used to characterize samples, well-separated groups corresponding to each of the species were observed by PCA and confirmed by CA and DA. The ‘‘width’’ and ‘‘length’’ of acorns exhibited a low discriminant power. Acorns from Q. rotundifolia showed the highest average oil content followed by Q. suber and Q. pyrenaica acorns (9.1, 5.2 and 3.8%, respectively. Fatty acid profiles of Q. rotundifolia and Q. suber oils are similar to olive oil while the oil from Q. pyrenaica acorns is more unsaturated.El objetivo de este estudio fué (i la caracterización de diferentes especies del género Quercus y (ii la clasificación de las mismas en base al contenido y composición de ácidos grasos del aceite de sus frutos y/o en sus caracteres morfológicos, via técnicas de patrón de reconocimiento (Análisis de Componentes Principales, ACP, Análisis de Cluster, AC, y Análisis Discriminante, AD. Se han estudiado Quercus rotundifolia Lam., Quercus suber L. y Quercus pyrenaica Willd., pertenecientes a la misma zona del centro de Portugal. Al emplear el contenido de aceite y sus respectivas composiciones de ácidos grasos para caracterizar a las muestras, el ACP reveló grupos bien separados correspondientes a cada especie, los cuales, a su vez, se confirmarón con el AC y el AD. El ‘‘ancho’’ y ‘‘longitud’’ de las bellotas

  5. Identification of DNA-microsatellite markers for the characterization of somatic embryos in Quercus suber.

    Science.gov (United States)

    Gómez-Garay, Arancha; Bueno, Angeles; Pintos, Beatriz

    2013-01-01

    Nuclear DNA-microsatellite markers led the possibility to characterize individually both Quercus suber trees and somatic embryos. The genotype inferred by SSR markers opens the possibility to obtain a fingerprint for clonal lines identification. Furthermore, allow to infer the origin of somatic embryos from haploid cells (microspores) or from diploid tissues. Using few SSR markers from other Quercus species and an automatic system based in fluorescence, it is possible to obtain a high discrimination power between genotypes. This method is sufficient to assign tissues to an individual tree with high statistical certainty. Nevertheless, it is necessary to take care to select the adequate DNA extraction method to avoid PCR inhibitors present in diverse Q. suber tissues.

  6. TRAVEL AND HOME LEAVE

    CERN Multimedia

    Human Resources Division

    2002-01-01

    Administrative procedures for : Travel to the home station and home leave (hl) Additional travel to the home station (at) Travel to the home station and home leave for family reasons (hlf) As part of the process of simplifying administrative procedures, HR and AS Divisions have devised a new, virtually automatic procedure for payment of travel expenses to the home station. The changes are aimed at rationalising administrative procedures and not at reducing benefits. The conditions of eligibility are unchanged. The new procedure, which will be operational with effect from 1st June 2002, will greatly simplify the administrative processing of claims for travel expenses and the recording of home leaves. Currently, requests for payment are introduced manually into the Advances and Claims system (AVCL) by divisional secretariats. All travel to the home station starting prior to 1st June 2002 will be processed according to the existing system whereas that starting on 1st June and after will be processed accordi...

  7. A neighborhood analysis of the consequences of Quercus suber decline for regeneration dynamics in Mediterranean forests.

    Science.gov (United States)

    Ibáñez, Beatriz; Gómez-Aparicio, Lorena; Stoll, Peter; Ávila, José M; Pérez-Ramos, Ignacio M; Marañón, Teodoro

    2015-01-01

    In forests, the vulnerable seedling stage is largely influenced by the canopy, which modifies the surrounding environment. Consequently, any alteration in the characteristics of the canopy, such as those promoted by forest dieback, might impact regeneration dynamics. Our work analyzes the interaction between canopy neighbors and seedlings in Mediterranean forests affected by the decline of their dominant species (Quercus suber). Our objective was to understand how the impacts of neighbor trees and shrubs on recruitment could affect future dynamics of these declining forests. Seeds of the three dominant tree species (Quercus suber, Olea europaea and Quercus canariensis) were sown in six sites during two consecutive years. Using a spatially-explicit, neighborhood approach we developed models that explained the observed spatial variation in seedling emergence, survival, growth and photochemical efficiency as a function of the size, identity, health, abundance and distribution of adult trees and shrubs in the neighborhood. We found strong neighborhood effects for all the performance estimators, particularly seedling emergence and survival. Tree neighbors positively affected emergence, independently of species identity or health. Alternatively, seedling survival was much lower in neighborhoods dominated by defoliated and dead Q. suber trees than in neighborhoods dominated by healthy trees. For the two oak species, these negative effects were consistent over the three years of the experimental seedlings. These results indicate that ongoing changes in species' relative abundance and canopy trees' health might alter the successional trajectories of Mediterranean oak-forests through neighbor-specific impacts on seedlings. The recruitment failure of dominant late-successional oaks in the gaps opened after Q. suber death would indirectly favor the establishment of other coexisting woody species, such as drought-tolerant shrubs. This could lead current forests to shift into

  8. A neighborhood analysis of the consequences of Quercus suber decline for regeneration dynamics in Mediterranean forests.

    Directory of Open Access Journals (Sweden)

    Beatriz Ibáñez

    Full Text Available In forests, the vulnerable seedling stage is largely influenced by the canopy, which modifies the surrounding environment. Consequently, any alteration in the characteristics of the canopy, such as those promoted by forest dieback, might impact regeneration dynamics. Our work analyzes the interaction between canopy neighbors and seedlings in Mediterranean forests affected by the decline of their dominant species (Quercus suber. Our objective was to understand how the impacts of neighbor trees and shrubs on recruitment could affect future dynamics of these declining forests. Seeds of the three dominant tree species (Quercus suber, Olea europaea and Quercus canariensis were sown in six sites during two consecutive years. Using a spatially-explicit, neighborhood approach we developed models that explained the observed spatial variation in seedling emergence, survival, growth and photochemical efficiency as a function of the size, identity, health, abundance and distribution of adult trees and shrubs in the neighborhood. We found strong neighborhood effects for all the performance estimators, particularly seedling emergence and survival. Tree neighbors positively affected emergence, independently of species identity or health. Alternatively, seedling survival was much lower in neighborhoods dominated by defoliated and dead Q. suber trees than in neighborhoods dominated by healthy trees. For the two oak species, these negative effects were consistent over the three years of the experimental seedlings. These results indicate that ongoing changes in species' relative abundance and canopy trees' health might alter the successional trajectories of Mediterranean oak-forests through neighbor-specific impacts on seedlings. The recruitment failure of dominant late-successional oaks in the gaps opened after Q. suber death would indirectly favor the establishment of other coexisting woody species, such as drought-tolerant shrubs. This could lead current

  9. First Report of Erannis defoliaria on Quercus sp. in North West of Tunisia

    OpenAIRE

    Yaussra Mannai; Olfa Ezzine; Saïd Nouira; Mohamed Lahbib Ben Jamâa

    2015-01-01

    Erannis defoliaria, a spring-feeding moth, caused severe defoliation during springs 2009 and 2010. Larvae were collected from Quercus suber in northwestern forest of Tunisia: Bellif and Ain El Baya. Caterpillars of E. defoliaria were also observed feeding on Q. canariensis, Q. afares and other shrub species such as Pistacia lentiscus, Erica arborea, and E. multiflora. In this paper, we present a first report of this pest in Tunisia.

  10. Removal of chromium (VI in aqueous environments using cork and heat-treated cork samples from Quercus cerris and Quercus suber

    Directory of Open Access Journals (Sweden)

    Ali Şen

    2012-11-01

    Full Text Available Chromium (VI removal and its reduction to chromium (III from aqueous solution by untreated and heat-treated Quercus cerris and heat-treated Quercus suber black agglomerate cork granules was investigated. Initial screening studies revealed that among the sorbents tested, untreated Q. cerris and Q. suber black agglomerate are the most efficient in the removal of Cr(VI ions and were selected for adsorption essays. Heat treatment adversely affected chromium adsorption and chromium (VI reduction in Q. cerris cork. The highest metal uptake was found at pH 3.0 for Q. cerris and pH 2.0 for black agglomerate. The experimental data fitted the Langmuir model and the calculated qmax was 22.98 mg/g in black agglomerate and 21.69 mg/g in untreated Q. cerris cork. The FTIR results indicated that while in black agglomerate, lignin is the sole component responsible for Cr(VI sorption, and in untreated Q. cerris cork, suberin and polysaccharides also play a significant role on the sorption. The SEM-EDX results imply that chromium has a homogenous distribution within both cork granules. Also, phloemic residues in Q. cerris granules showed higher chromium concentration. The results obtained in this study show that untreated Q. cerris and black agglomerate cork granules can be an effective and economical alternative to more costly materials for the treatment of liquid wastes containing chromium.

  11. Xylem-Transported Glucose as an Additional Carbon Source for Leaf Isoprene Formation in Quercus Robur L.

    Science.gov (United States)

    Graus, M.; Kreuzwieser, J.; Schnitzler, J.; Wisthaler, A.; Hansel, A.; Rennenberg, H.

    2003-04-01

    Isoprene is emitted from mature, photosynthesizing leaves of many plant species, particularly of trees. Current interest in understanding the biochemical and physiological mechanisms controlling isoprene formation is caused by the important role isoprene plays in atmospheric chemistry. Isoprene reacts with hydroxyl radicals (OH) thereby generating oxidizing agents such as ozone and organic peroxides. Ozone causes significant deterioration in air quality and can pose threats to human health therefore its control is a major goal in Europe and the United States. In recent years, much progress has been made in elucidating the pathways of isoprene biosynthesis. Nevertheless the regulatory mechanisms controlling isoprene emission are not completely understood. Light and temperature appear to be the main factors controlling short-term variations in isoprene emission. Exposure of plants to C-13 labeled carbon dioxide showed instantaneous assimilated carbon is the primary carbon source for isoprene formation. However, variations in diurnal and seasonal isoprene fluxes, which cannot be explained by temperature, light, and leaf development led to the suggestion that alternative carbon sources may exist contributing to isoprene emissions. The aim of the present study was to test whether xylem-transported carbohydrates act as additional sources for isoprene biosynthesis. For this purpose, [U-C-13] alpha-D-glucose was fed to photosynthesizing leaves via the xylem of Quercus robur L. seedlings and the incorporation of glucose derived C-13 into emitted isoprene was monitored in real time using Proton-Transfer-Reaction Mass Spectrometry (PTR-MS). A rapid incorporation of C-13 from xylem-fed glucose into single (mass 70) and double (mass 71) C-13 labeled isoprene molecules was observed after a lag phase of approximately 5 to 10 minutes. This incorporation was temperature dependent and was highest (up to 13% C-13 of total carbon emitted as isoprene) at the temperature optimum of

  12. REMINDER: Saved Leave Scheme (SLS)

    CERN Multimedia

    2003-01-01

    Transfer of leave to saved leave accounts Under the provisions of the voluntary saved leave scheme (SLS), a maximum total of 10 days'* annual and compensatory leave (excluding saved leave accumulated in accordance with the provisions of Administrative Circular No 22B) can be transferred to the saved leave account at the end of the leave year (30 September). We remind you that unused leave of all those taking part in the saved leave scheme at the closure of the leave year accounts is transferred automatically to the saved leave account on that date. Therefore, staff members have no administrative steps to take. In addition, the transfer, which eliminates the risk of omitting to request leave transfers and rules out calculation errors in transfer requests, will be clearly shown in the list of leave transactions that can be consulted in EDH from October 2003 onwards. Furthermore, this automatic leave transfer optimizes staff members' chances of benefiting from a saved leave bonus provided that they ar...

  13. Does Leave Work?

    NARCIS (Netherlands)

    Heleen van Luijn; Saskia Keuzenkamp

    2004-01-01

    More and more people have to combine work and care responsibilities, and work part-time or use daycare and after-school care facilities to help them do so. The Work and Care Act, which came into force on 1 December 2001, combined all the existing schemes - such as parental and maternity leave -

  14. Maternity Leave in Taiwan

    Science.gov (United States)

    Feng, Joyce Yen; Han, Wen-Jui

    2010-01-01

    Using the first nationally representative birth cohort study in Taiwan, this paper examines the role that maternity leave policy in Taiwan plays in the timing of mothers returning to work after giving birth, as well as the extent to which this timing is linked to the amount of time mothers spend with their children and their use of breast milk…

  15. Leaves: Nature's Solar Collectors

    Science.gov (United States)

    Isabelle, Aaron D.; de Groot, Cornelis

    2009-01-01

    One of the most captivating things about plants is the way they capture the Sun's energy, but this can be a difficult topic to cover with elementary students. Therefore, to help students to make a concrete connection to this abstract concept, this series of solar-energy lessons focuses on leaves and how they act as "solar collectors." As students…

  16. Wing Infrastructure Development Outlook: Programmatic Environmental Assessment

    Science.gov (United States)

    2005-07-01

    live oaks (Quercus ruba), red oaks (Quercus sp.), pecan (Carya sp.), bur oaks (Quercus macrocarpa), mesquite ( Prosopis sp.), Afghan pine (Pinus...which causes shear breaks in water lines. The first phase of replacing the existing rigid cast iron and asbestos cement pipes with resilient plastic

  17. Accumulation of sulfur and heavy metals in soil and tree leaves sampled from the surroundings of Tuncbilek Thermal Power Plant.

    Science.gov (United States)

    Cicek, A; Koparal, A S

    2004-11-01

    In this study, the quantities of sulfur and heavy metals, resulting from the Tuncbilek Thermal Power Plant (TPP) in Turkey, have been assessed in tree leaves and soil samples within a 10 km radius of the plant. Leaves of Salix alba L., Populus tremula L., Robinia pseudoacacia L., Quercus infectoria L., Pinus nigra Arn. ssp. pallasiana (Lamb) Holmboe. trees have been used with the aim of determining how far the gas and particles emitted from the TPP are carried, and for assessment of environmental impact. The results obtained from locations chosen at various distances to the TPP, indicate that the contaminating agents are very dense and effective; particularly in the prevailing wind direction and within 10 km of the plant. They gradually lose their density and effect beyond this distance. The sulfur and heavy metal analyses made in soils taken from these locations indicate a similarity with the data obtained from the leaves.

  18. Effect of simulated acid rain on the litter decomposition of Quercus acutissima and Pinus massoniana in forest soil microcosms and the relationship with soil enzyme activities.

    Science.gov (United States)

    Wang, Congyan; Guo, Peng; Han, Guomin; Feng, Xiaoguang; Zhang, Peng; Tian, Xingjun

    2010-06-01

    With the continuing increase in human activities, ecologists are increasingly interested in understanding the effects of acid rain on litter decomposition. Two dominant litters were chosen from Zijin Mountain in China: Quercus acutissima from a broad-leaved forest and Pinus massoniana from a coniferous forest. The litters were incubated in microcosms and treated with simulated acid rain (gradient pH levels). During a six-month incubation, changes in chemical composition (i.e., lignin, total carbohydrate, and nitrogen), litter mass losses, soil pH values, and activities of degradative enzymes were determined. Results showed that litter mass losses were depressed after exposure to acid rain and the effects of acid rain on the litter decomposition rates of needles were higher than on those of leaves. Results also revealed that simulated acid rain restrained the activities of cellulase, invertase, nitrate reductase, acid phosphatase, alkaline phosphatase, polyphenol oxidase, and urease, while it enhanced the activities of catalase in most cases during the six-month decomposition process. Catalase and polyphenol oxidase were primarily responsible for litter decomposition in the broad-leaved forest, while invertase, nitrate reductase, and urease were primarily responsible for litter decomposition in the coniferous forest. The results suggest acid rain-restrained litter decomposition may be due to the depressed enzymatic activities. According to the results of this study, soil carbon in subtropical forests would accumulate as a long-term consequence of continued acid rain. This may presumably alter the balance of ecosystem carbon flux, nutrient cycling, and humus formation, which may, in turn, have multiple effects on forest ecosystems.

  19. 5 CFR 630.1117 - Procedures for returning unused donated annual leave to emergency leave donors and leave banks.

    Science.gov (United States)

    2010-01-01

    ... annual leave to emergency leave donors and leave banks. 630.1117 Section 630.1117 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS ABSENCE AND LEAVE Emergency Leave Transfer Program § 630.1117 Procedures for returning unused donated annual leave to emergency leave...

  20. Negotiating leave in the workplace

    DEFF Research Database (Denmark)

    Bloksgaard, Lotte

    2014-01-01

    In Denmark leave entitlement is not only regulated by law but is also part of the various collective agreements established in the respective occupational sectors and at the local workplace level. Consequently, Danish fathers have very different leave entitlements, depending on the sector, branch...... men’s negotiations of parental leave at work place level and secondly, to explore and discuss how Danish fathers construct leave practices – and individual male identities – in the workplace....

  1. Characterization of Acorn Fruit Oils Extracted from Selected Mediterranean Quercus Species

    Directory of Open Access Journals (Sweden)

    Al-Rousan, W. M.

    2013-12-01

    Full Text Available The present study is aimed to identifying the acorn fruit oil composition of three Mediterranean white oak group species, Quercus aegilops (QA, Quercus infectoria (QI, and Quercus calliprinus (QC. Samples were estimated for the oil contents of acorn fruits, oil chemical and physical constants, fatty acid profile, tocopherols, phenolic compounds, and sterols.The oil content, expressed as dry weight, was found to be 3.40-7.51%. The physical and chemical constants included specific gravity 0.912-0.922, refractive index 1.4529-1.4645, specific extinction at 232 nm 2.497-2.536 and at 270 nm 1.495-2.037, iodine value 75.2-87.6, and saponification value 192.6-219.4. The fatty acid compositions were determined by GC as methyl esters. The most abundant fatty acids were oleic (53.3-56.1%, linoleic 21.3-23.4%, palmitic 17.8-18.7%, linolenic 1.5-1.6% and stearic acid 1.02-1.60%. The Tocopherol content was high in the range of 1440-1783 mg kg-1, γ-tocopherol constituted 84-91% of total tocopherols. Phenolic compounds were in remarkable amounts in all the three species 84-109 mg gallic acid kg-1 oil. Total sterol contents were between 2040-2480 mg kg-1 oil, with β-sitosterol being the main component comprising of 77.20-84.61%, followed by ∆5-avenasterol (5.8-11.4%, campesterol (3.6-4.5%, and stigmasterol (2.6-3.8. The cholesterol content was relatively high (0.42-0.55%.El presente estudio tuvo como objetivo identificar la composición de aceites de bellota de tres especies del grupo del roble blanco del Mediterráneo, Quercus Aegilops (QA, Quercus infectoria (QI y Quercus calliprinus (QC. Las muestras fueron evaluadas por el contenido de aceite, parámetros físico-químicos del aceite, perfil de ácidos grasos, tocoferoles, compuestos fenólicos y esteroles. El contenido de aceite, expresado en peso seco encontrado fue de 3,40 a 7,51%. Las constantes físico-químicas fueron: densidad 0,912-0,922, índice de refracción 1,4529 a 1,4645, extinción espec

  2. Saved Leave Scheme (SLS) : Simplified procedure for the transfer of leave to saved leave accounts

    CERN Multimedia

    HR Division

    2001-01-01

    As part of the process of streamlining procedures, the HR and AS Divisions have jointly developed a system whereby annual and compensatory leave will henceforth be automatically transferred1) to saved leave accounts. Under the provisions of the voluntary saved leave scheme (SLS), a maximum total of 10 days'2) annual and compensatory leave (excluding saved leave accumulated in accordance with the provisions of Administrative Circular No. 22 B) can be transferred to the saved leave account at the end of the leave year (30 September). Previously, every person taking part in the scheme has been individually issued with a form for the purposes of requesting the transfer of leave to the leave account and the transfer has then had to be done manually by HR Division. To streamline the procedure, unused leave of all those taking part in the saved leave scheme at the closure of of the leave-year accounts will henceforth be transferred automatically to the saved leave account on that date. This simplification is in the ...

  3. REMINDER Saved Leave Scheme (SLS) : Transfer of leave to saved leave accounts

    CERN Document Server

    HR Division

    2002-01-01

    Under the provisions of the voluntary saved leave scheme (SLS), a maximum total of 10 days'*) annual and compensatory leave (excluding saved leave accumulated in accordance with the provisions of Administrative Circular No. 22B) can be transferred to the saved leave account at the end of the leave year (30 September). We remind you that, since last year, unused leave of all those taking part in the saved leave scheme at the closure of the leave-year accounts is transferred automatically to the saved leave account on that date. Therefore, staff members have no administrative steps to take. In addition, the transfer, which eliminates the risk of omitting to request leave transfers and rules out calculation errors in transfer requests, will be clearly shown in the list of leave transactions that can be consulted in EDH from October 2002 onwards. Furthermore, this automatic leave transfer optimizes staff members' chances of benefiting from a saved leave bonus provided that they are still participants in the schem...

  4. Fitotoxicidad del fosfonato en brinzales de encina Quercus ilex L. subsp. ballota (Desf.) Samp.

    OpenAIRE

    Jorge, Inmaculada; Porras Tejero, Carlos Javier; Jorrín-Novo, Jesús V.; Ariza-Mateos, David; Navarro Cerrillo, Rafael M.

    2007-01-01

    El fosfonato es un fertilizante foliar que ha sido utilizado con éxito en el control de P. cinnamomi en varias especies forestales. Aunque se considera que los fosfonatos tienen un bajo nivel de toxicidad, se han observado síntomas de daños en varias especies y utilizando distintos métodos de aplicación. En este trabajo se estudia la fitotoxicidad de los fosfonatos en brinzales de Quercus ilex. Se han ensayado dos concentraciones de fosfonato, 10 y 15 g l-1, y se han realizado medidas de la f...

  5. Caracterización energética de Quercus robur L.

    OpenAIRE

    González Rodríguez, Alberto Jesús

    2016-01-01

    En esta Tesis se buscan justificaciones sólidas que respalden la implantación de un proceso de silvicultura eficaz aplicable a las masas de Quercus con el doble objetivo de sanearlas a la vez que extraer de ellas biomasa forestal de calidad utilizable en procesos de producción energética a pequeña escala. Para conseguir estos dos objetivos debemos primero plantear la importancia actual del carballo en Galicia en su contexto más global y justificar así una inversión importante en labores silví...

  6. Intrapopulation and Interpopulation Genetic Variation ofQuercus in Denmark in Denmark

    DEFF Research Database (Denmark)

    Siegismund, Hans Redlef; Jensen, Jan Svejgaard

    2001-01-01

    Native Danish oak stands are fragmented and decreasing because of the extensive use of foreign seed sources. Therefore, the population structure of natural Danish oak stands was analysed by means of six polymorphic enzyme loci. A total of 17 stands of Quercus robur L. (including an ‘‘outgroup......-Weinberg proportions, suggesting a low level of inbreeding. The differentiation of the Q. petraea and Q. robur populations was quanti. ed with Wright's F-statistics. The within-species component was populations was quanti. ed with Wright's -statistics. The within-species component was low, 0.022, re¿ ecting the wind...

  7. Drying of the aqueous extract of acorn Quercus robur in a spout-fluid bed

    Directory of Open Access Journals (Sweden)

    Rakić S.

    2005-01-01

    Full Text Available The results of the chemical investigations of variously treated acorn samples are presented in this paper with the aim of obtaining data on the amount of nutritious components and biologically active substances. The Quercus robur acorn, which belongs to the Fagaceae family, was investigated in a raw, thermally treated form and as an extract that was subsequently dried in a dryer with a fluidized bed. The obtained results regarding the content of tannin, nitrogen containing compounds, macro- and microelements indicate that acorn maintains its functional characteristics after the investigated treatments.

  8. Comparison between ethanol and hexane for oil extraction from Quercus suber L. fruits

    Directory of Open Access Journals (Sweden)

    Abreu, José M.F.

    2003-12-01

    Full Text Available The aim of this study was to (i evaluate the feasibility of replacing n-hexane with ethanol for the extraction of oil from Quercus suber fruits and (ii optimize, at lab scale, sample preparation and extraction time for both solvents used (n-hexane vs. anhydrous ethanol. For both solvents, the effect of the conditioning process on extraction yield was evaluated. Therefore, a full factorial design was used as a function of four variables: dehulling (with vs. without husks, and thermal treatment of the crushed material (40ºC vs. 75ºC, at different times (5 min vs. 120 min and pressures (10 kPa vs. 100 kPa. Higher oil yields were obtained with n-hexane when dehulled fruits were conditioned under atmospheric pressure. Better yields were obtained with n-hexane, when dehulled material was treated at 75ºC for 90 min. Ethanol was not adequate for oil extraction from Quercus fruits, since other materials rather than oil were also extracted.El objetivo de este estudio fue (i evaluar la posibilidad de reemplazar el n-hexano por el etanol para la extracción del aceite de los frutos de Quercus suber y (ii optimizar, a escala de laboratorio, la preparación de la muestra y el tiempo de extracción para ambos solventes (n-hexano vs. etanol anhidro. Para ambos solventes, se ha evaluado el efecto del proceso de acondicionamiento en el rendimiento de la extracción. Para ello, se ha empleado un diseño factorial completo como función de cuatro variables: descascarillado (con vs sin cascarilla, y tratamiento térmico del material triturado (40ºC vs. 75ºC, a diferentes tiempos (5 min vs. 120 min y presiones (10 kPa vs. 100 kPa. Los rendimientos más elevados de extracción de aceite se obtuvieron con n-hexano cuando los frutos descascarillados se acondicionaron a presión atmosférica. Cuando el material descascarillado fue tratado a 75ºC por 90 min, se obtuvieron mejores rendimientos con n-hexano. El etanol demostró no ser adecuado para la

  9. Genetic transformation of cork oak (Quercus suber L.) for herbicide resistance.

    Science.gov (United States)

    Alvarez, Rubén; Alvarez, José M; Humara, Jaime M; Revilla, Angeles; Ordás, Ricardo J

    2009-09-01

    The bar gene was introduced into the cork oak genome. Cork oak embryogenic masses were transformed using the Agrobacterium strain AGL1 which carried the plasmid pBINUbiBar. This vector harbours the genes, nptII and bar, the latter under control of the maize ubiquitin promoter. The transgenic embryogenic lines were cryopreserved. Varying activities of phosphinothricin acetyl transferase were detected among the lines, which carried 1-4 copies of the insert. Molecular and biochemical assays confirmed the stability and expression of the transgenes 3 months after thawing the cultures. These results demonstrate genetic engineering of herbicide tolerance in Quercus spp.

  10. Histological investigation of the multiplication step in secondary somatic embryogenesis of Quercus robur L.

    OpenAIRE

    2001-01-01

    International audience; Standardized explants composed of hypocotyl and root-tip were prepared from embryonic structures obtained from one embryogenic line of Quercus robur L. maintained by regular transfer onto a solidified reference medium composed of the MS mineral solutions, glucose (0.12 M), casamino acid (0.1% ), and NAA (10.74 $\\mu$M). The regeneration capacity from these explants were tested on the reference medium and on 2 alternative media in which the NAA (10.74 $\\mu$M) was omitted...

  11. Effects of two sources of tannins (Quercus L. and Vaccinium vitis idaea L. on rumen microbial fermentation: an in vitro study

    Directory of Open Access Journals (Sweden)

    Adam Cieslak

    2014-04-01

    Full Text Available The aim of the experiment was to determine the effect of different sources of tannins on the in vitro rumen fermentation with focus on methane production. In the experiment, a rumen simulation system (RUSITEC equipped with 4 fermenters (1 L was used in three replicated runs (6 d of adaptation and 4 d of sampling to study the effects of Quercus cortex extract (QC, Vaccinium vitis idaea (VVI dried leaf extract and a mixture of VVI/QC on rumen microbial fermentation. Fermenters were fed 10.9 g/d of dry matter (DM of a 600:400 forage:concentrate diet. Treatments were control, QC (2.725 mL, VVI leaves 0.080 g and mixture of QC/VVI (1.362 mL+0.040 g and were randomly assigned to fermenters within periods. The equivalent of 2.5 g of tannins/kg dietary DM from three sources of tannins was evaluated. All tannin sources decreased CH4 and ammonia concentrations, as well as protozoa and methanogen counts (P<0.001. Vaccinium vitis idaea and QC/VVI tended (P=0.005 to reduce the acetate to propionate ratio. There were no changes in nutrient digestion. Results suggest that these sources of tannins, especially VVI have the potential to reduce rumen CH4 production and ammonia concentration without negative effects on in vitro DM digestibility, total volatile fatty acids and pH.

  12. Ectomycorrhizal association of three Lactarius species with Carpinus and Quercus trees in a Mexican montane cloud forest.

    Science.gov (United States)

    Lamus, Valentina; Montoya, Leticia; Aguilar, Carlos J; Bandala, Victor M; Ramos, David

    2012-01-01

    Ectomycorrhizal (EM) fungi are being monitored in the Santuario del Bosque de Niebla in the central region of Veracruz (eastern Mexico). Based on the comparison of DNA sequences (ITS rDNA) of spatiotemporally co-occurring basidiomes and EM root tips, we discovered the EM symbiosis of Lactarius indigo, L. areolatus and L. strigosipes with Carpinus caroliniana, Quercus xalapensis and Quercus spp. The host of the EM tips was identified by comparison of the large subunit of the ribulose-bisphosphate carboxylase gene (rbcL). Descriptions coupled with photographs of ectomycorrhizas and basidiomes are presented.

  13. Flash-flood impacts cause changes in wood anatomy of Alnus glutinosa, Fraxinus angustifolia and Quercus pyrenaica.

    Science.gov (United States)

    Ballesteros, J A; Stoffel, M; Bollschweiler, M; Bodoque, J M; Díez-Herrero, A

    2010-06-01

    Flash floods may influence the development of trees growing on channel bars and floodplains. In this study, we analyze and quantify anatomical reactions to wounding in diffuse-porous (Alnus glutinosa L.) and ring-porous (Fraxinus angustifolia Vahl. and Quercus pyrenaica Willd.) trees in a Mediterranean environment. A total of 54 cross-sections and wedges were collected from trees that had been injured by past flash floods. From each of the samples, micro-sections were prepared at a tangential distance of 1.5 cm from the injury to determine wounding-related changes in radial width, tangential width and lumen of earlywood vessels, and fibers and parenchyma cells (FPC). In diffuse-porous A. glutinosa, the lumen area of vessels shows a significant (non-parametric test, P-value <0.05) decrease by almost 39% after wounding. For ring-porous F. angustifolia and Q. pyrenaica, significant decreases in vessel lumen area are observed as well by 59 and 42%, respectively. Radial width of vessels was generally more sensitive to the decrease than tangential width, but statistically significant values were only observed in F. angustifolia. Changes in the dimensions of earlywood FPC largely differed between species. While in ring-porous F. angustifolia and Q. pyrenaica the lumen of FPC dropped by 22 and 34% after wounding, we observed an increase in FPC lumen area in diffuse-porous A. glutinosa of approximately 35%. Our data clearly show that A. glutinosa represents a valuable species for flash-flood research in vulnerable Mediterranean environments. For this species, it will be possible in the future to gather information on past flash floods with non-destructive sampling based on increment cores. In ring-porous F. angustifolia and Q. pyrenaica, flash floods leave less drastic, yet still recognizable, signatures of flash-flood activity through significant changes in vessel lumen area. In contrast, the use of changes in FPC dimensions appears less feasible for the determination of

  14. Negotiating leave in the workplace

    DEFF Research Database (Denmark)

    Bloksgaard, Lotte

    In Denmark leave entitlement is not only regulated by law but is also part of the various collective agreements established in the respective occupational sectors and at the local workplace level. Consequently, Danish fathers have very different leave entitlements, depending on the sector, branch...... and workplace in which they are employed. The paper focuses on fathers’ negotiations of parental leave in three large Danish work places, offering men different opportunities for leave. With a focus on the differences in the work place contexts/opportunities for leave, the aim of the paper is firstly to explore...... men’s negotiations of parental leave at work place level and secondly, to explore and discuss how Danish fathers construct leave practices – and individual male identities – in the workplace....

  15. Negotiating leave in the workplace

    DEFF Research Database (Denmark)

    Bloksgaard, Lotte

    2014-01-01

    In Denmark leave entitlement is not only regulated by law but is also part of the various collective agreements established in the respective occupational sectors and at the local workplace level. Consequently, Danish fathers have very different leave entitlements, depending on the sector, branch...... and workplace in which they are employed. The paper focuses on fathers’ negotiations of parental leave in three large Danish work places, offering men different opportunities for leave. With a focus on the differences in the work place contexts/opportunities for leave, the aim of the paper is firstly to explore...... men’s negotiations of parental leave at work place level and secondly, to explore and discuss how Danish fathers construct leave practices – and individual male identities – in the workplace....

  16. Analytical approaches to the determination of simple biophenols in forest trees such as Acer (maple), Betula (birch), Coniferus, Eucalyptus, Juniperus (cedar), Picea (spruce) and Quercus (oak).

    Science.gov (United States)

    Bedgood, Danny R; Bishop, Andrea G; Prenzler, Paul D; Robards, Kevin

    2005-06-01

    Analytical methods are reviewed for the determination of simple biophenols in forest trees such as Acer (maple), Betula (birch), Coniferus, Eucalyptus, Juniperus (cedar), Picea (spruce) and Quercus (oak). Data are limited but nevertheless clearly establish the critical importance of sample preparation and pre-treatment in the analysis. For example, drying methods invariably reduce the recovery of biophenols and this is illustrated by data for birch leaves where flavonoid glycosides were determined as 12.3 +/- 0.44 mg g(-1) in fresh leaves but 9.7 +/- 0.35 mg g(-1) in air-dried samples (data expressed as dry weight). Diverse sample handling procedures have been employed for recovery of biophenols. The range of biophenols and diversity of sample types precludes general procedural recommendations. Caution is necessary in selecting appropriate procedures as the high reactivity of these compounds complicates their analysis. Moreover, our experience suggests that their reactivity is very dependent on the matrix. The actual measurement is less contentious and high performance separation methods particularly liquid chromatography dominate analyses whilst coupled techniques involving electrospray ionization are becoming routine particularly for qualitative applications. Quantitative data are still the exception and are summarized for representative species that dominate the forest canopy of various habitats. Reported concentrations for simple phenols range from trace level (<0.1 microg g(-1)) to in excess of 500 microg g(-1) depending on a range of factors. Plant tissue is one of these variables but various biotic and abiotic processes such as stress are also important considerations.

  17. Photosystem II efficiency of the palisade and spongy mesophyll in Quercus coccifera using adaxial/abaxial illumination and excitation light sources with wavelengths varying in penetration into the leaf tissue.

    Science.gov (United States)

    Peguero-Pina, José Javier; Gil-Pelegrín, Eustaquio; Morales, Fermín

    2009-01-01

    The existence of major vertical gradients within the leaf is often overlooked in studies of photosynthesis. These gradients, which involve light heterogeneity, cell composition, and CO(2) concentration across the mesophyll, can generate differences in the maximum potential PSII efficiency (F (V)/F (M) or F (V)/F (P)) of the different cell layers. Evidence is presented for a step gradient of F (V)/F (P) ratios across the mesophyll, from the adaxial (palisade parenchyma, optimal efficiencies) to the abaxial (spongy parenchyma, sub-optimal efficiencies) side of Quercus coccifera leaves. For this purpose, light sources with different wavelengths that penetrate more or less deep within the leaf were employed, and measurements from the adaxial and abaxial sides were performed. To our knowledge, this is the first report where a low photosynthetic performance in the abaxial side of leaves is accompanied by impaired F (V)/F (P) ratios. This low photosynthetic efficiency of the abaxial side could be related to the occurrence of bundle sheath extensions, which facilitates the penetration of high light intensities deep within the mesophyll. Also, leaf morphology (twisted in shape) and orientation (with a marked angle from the horizontal plane) imply direct sunlight illumination of the abaxial side. The existence of cell layers within leaves with different photosynthetic efficiencies makes appropriate the evaluation of how light penetrates within the mesophyll when using Chl fluorescence or gas exchange techniques that use different wavelengths for excitation and/or for driving photosynthesis.

  18. Seasonal variability of interception and water wettability of common oak leaves

    Directory of Open Access Journals (Sweden)

    Anna Klamerus-Iwan

    2014-01-01

    Full Text Available Wettability of leaves and the resulting amount of interception loss of tree crowns is an important component of the atmosphere-tree stand-soil system balance. In the study, we hypothesized that changes occurring in leaves during the vegetation period can significantly affect the amount of rainwater retained by plants and wettability of leaves which is expressed by the contact angle between drops and leaves. We evaluated the hypothesis based on measurement series, which combined direct spraying of leaves with water at different stages of development at a constant temperature with observations made with an electron scanner which was used to determine changes occurring within a leaf, while the photographic method was used to analyze the contact angle of drops. The study involved common oak (Quercus robur. Samples of twigs derived from this species were collected in the area of Przedbórz (Poland forest district, in particular from the trees with well-developed crowns. Twigs were collected from 10 trees of similar age (35–40 years. The resulting database contained experimental data on changes of raindrop adhesion on oak leaves throughout the growing season. The internal contact angle of drops was within the range of 150° on the upper side of the leaf and 160° on the underside in May, up to 15° and 35° in November on the upper and underside of the leaves. Loss of interception was established at 6% at the beginning of the growing season up to 22% in autumn. It was concluded that the wettability and the level of interception increases in line with the age of a leaf.

  19. Elemental concentrations in deposited dust on leaves along an urbanization gradient.

    Science.gov (United States)

    Simon, Edina; Baranyai, Edina; Braun, Mihály; Cserháti, Csaba; Fábián, István; Tóthmérész, Béla

    2014-08-15

    Environmental health is an essential component of the quality of life in modern societies. Monitoring of environmental quality and the assessment of environmental risks are often species based on the elemental concentration of deposited dust. Our result suggested that stomata size and distribution were the most important factors influencing the accumulation of air contaminants in leaves. We found that the leaves' surfaces of Acer negundo and Celtis occidentalis were covered by a large number of trichomes, and these species have proven to be suitable biomonitors for atmospheric pollution difficult; these can be overcome using bioindicator species. Leaves of Padus serotina, Acer campestre, A. negundo, Quercus robur and C. occidentalis were used to assess the amount of deposited dust and the concentration of contaminants in deposited dust in and around the city of Debrecen, Hungary. Samples were collected from an urban, suburban and rural area along an urbanization gradient. The concentrations of Ba, Cu, Fe, Mn, Ni, Pb, S, Sr and Zn were determined in deposited dust using ICP-OES. Scanning electron microscopy (SEM) was used to explore the morphological structure and dust absorbing capacity of leaves. We found significant differences in dust deposition among species, and dust deposition correlated with trichomes' density. Principal component analysis (PCA) also showed a total separation of tree.

  20. Leaf morphology correlates with water and light availability:What consequences for simple and compound leaves?

    Institute of Scientific and Technical Information of China (English)

    Fei Xu; Weihua Guo; Weihong Xu; Yinghua Wei; Renqing Wang

    2009-01-01

    Leaves are organs sensitive to environmental changes in the process of evolution and may exhibit phenotypic plasticity as a response to abiotic stress.However,affirmation of leaf morphological plasticity and its regulations in different environments are still unclear.We performed a simulated experiment to study the variations of leaf morphology in different gradients of water and light availability.Considering different types of leaves and venation,we chose pinnate-veined simple leaves of Quercus acutissima and compound leaves of Robinia pseudoacacia as the study objects.The morphological parameters we investigated include leaf size,shape and venation pattern which can be easily measured in the field.Significant variations occurred in many parameters due to the effects of the environment and/or allometry.There were broadly consistent trends for leaf morphological variations along the gradients.The leaf size became smaller with a short supply of resources.Leaf elongation and fractions of the lamina area altered to enhance resources acquisition and conservation.Trade-offs between investments in support and functional structures optimized the venation pattern of major and minor veins.Leaflets partially played a role such as leaf teeth,for they are not only individual units,but also a part of the compound leaf.We suggest that more or less the same trends in morphological variations may be an important explanation for coexisting species to adapt to similar habitats and form the niche differentiation.

  1. Comparative of Quercus spp. and Salix spp. for phytoremediation of Pb/Zn mine tailings.

    Science.gov (United States)

    Shi, Xiang; Wang, Shufeng; Sun, Haijing; Chen, Yitai; Wang, Dongxue; Pan, Hongwei; Zou, Yazhu; Liu, Jianfeng; Zheng, Linyu; Zhao, Xiulian; Jiang, Zeping

    2017-02-01

    A pot experiment was conducted to evaluate the feasibility of using tree seedlings for the phytoremediation of lead/zinc (Pb/Zn) mine tailings. Seedlings of three Quercus spp. (Q. shumardii, Q. phellos, and Q. virginiana) and rooted cuttings of two Salix spp. (S. matsudana and S. integra) were transplanted into pots containing 50 and 100 % Pb/Zn mine tailings to evaluate their tolerance of heavy metals. The five species showed different tolerance levels to the Pb/Zn tailings treatments. Q. virginiana was highly tolerant to heavy metals and grew normally in the Pb/Zn tailings. The root systems showed marked differences between the Quercus spp. and Salix spp., indicating that different mechanisms operated to confer tolerance of heavy metals. The maximum efficiency of photosystem II photochemistry value of the five species showed no differences among the treatments, except for Q. shumardii. All species showed low metal translocation factors (TFs). However, S. integra had significantly higher TF values for Zn (1.42-2.18) and cadmium (1.03-1.45) than did the other species. In this respect, Q. virginiana showed the highest tolerance and a low TF, implying that it is a candidate for phytostabilization of mine tailings in southern China. S. integra may be useful for phytoextraction of tailings in temperate regions.

  2. Polyphenol deposition in leaf hairs of Olea europaea (Oleaceae) and Quercus ilex (Fagaceae).

    Science.gov (United States)

    Karabourniotis, G; Kofidis, G; Fasseas, C; Liakoura, V; Drossopoulos, I

    1998-07-01

    The subcellular localization (cytoplasm, vacuoles, cell walls) of polyphenol compounds during the development of the multicellular nonglandular leaf hairs of Olea europaea (scales) and Quercus ilex (stellates), was investigated. Hairs of all developmental stages were treated with specific inducers of polyphenol fluorescence, and the bright yellow-green fluorescence of individual hairs was monitored with epifluorescence microscopy. During the early ontogenetic stages, bright fluorescence was emitted from the cytoplasm of the cells composing the multicellular shield of the scales of O. europaea. Transmission electron micrographs of the same stages showed that these cells possessed poor vacuolation and thin cell walls. The nucleus of these cells may be protected against ultraviolet-B radiation damage. The progressive vacuolation that occurred during maturation was followed by a shifting of the bright green-yellow fluorescence from the perinuclear region and the cytoplasm to the cell walls. The same trends were observed during the development of the nonglandular stellate hairs of Quercus ilex, in which maturation was also accompanied by a considerable secondary thickening of the cell walls. Despite the differences in morphology, high concentrations of polyphenol compounds are initially located mainly in the cytoplasm of the developing nonglandular hairs, and their deposition on the cell walls takes place during the secondary cell wall thickening. These structural changes during the development of the leaf hairs make them a very effective barrier against abiotic (uv-B radiation) and probably biotic (pathogenic) stresses.

  3. Isolation of antibacterial compounds from Quercus dilatata L. through bioassay guided fractionation

    Directory of Open Access Journals (Sweden)

    Jamil Maryam

    2012-05-01

    Full Text Available Abstract Background Four medicinal plants (Chrozophora hierosolymitana Spreng, Chrysanthemum leucanthemum L., Ephedra gerardiana Wall. ex Stapf, and Quercus dilatata L. used by indigenous healers to treat various infectious diseases were selected for the present study. The major objective of the present study was isolation and characterization of antimicrobial components from the crude plant extracts using bioassay guided fractionation. Methods Seven methanolic extracts of the four plants were screened to identify any antimicrobial agents present in them. The active crude plant extract was fractionated first by solvent partitioning and then by HPLC. Characterization of the active fractions was done by using spectrophotometer. Results All the seven methanolic extracts showed low antifungal activity, however, when these extracts were tested for antibacterial activity, significant activity was exhibited by two extracts. The extract of aerial parts of Q. dilatata was most active and therefore, was selected for further analysis. Initially fractionation was done by solvent-solvent partitioning and out of six partitioned fractions, ethanol fraction was selected on the basis of results of antibacterial activity and phytochemical analysis. Further, fractionation was carried out by RP- HPLC and purified active subfractions were characterized by comparing their absorption spectra with that of the known natural products isolated from the plants of Quercus genus. Discussion and conclusion The results suggest that this is the first report of the isolated antibacterial compounds from this genus.

  4. Post-fire ecological restoration of a mixed Pinus-Quercus forest in northeastern Mexico

    Directory of Open Access Journals (Sweden)

    Eduardo Alanís-Rodríguez

    2015-01-01

    Full Text Available La presente investigación se desarrolló en un bosque de Pinus-Quercus en el Parque Ecológico Chipinque (noreste de México, el cual fue afectado por un incendio forestal y sometido a tratamiento de restauración ecológica. Los objetivos fueron evaluar el establecimiento artificial de Pinus pseudostrobus (Lindl. y analizar el efecto de las barreras de retención de suelo después de 10 años de su instalación. Para ello se estableció un área de estudio con tratamiento de restauración ecológica y otra área sin tratamiento en las que se muestreó la comunidad vegetal y la profundidad del suelo. De acuerdo con los resultados, se registró 35 % de supervivencia de la plantación, la cual se considera como no aceptable. Las barreras de retención de suelo tuvieron efecto positivo, pues incrementaron la profundidad del suelo hasta 25 %. Con la investigación se concluye que las técnicas de restauración post-incendio aplicadas han sido eficaces, ya que incorporan una especie clave de ecosistemas maduros y evitan la pérdida de suelo por arrastre, por lo que se recomienda su uso en rodales de Pinus-Quercus afectados por incendios en la Sierra Madre Oriental.

  5. 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.

    Science.gov (United States)

    Lichtenthaler, Hartmut K; Babani, Fatbardha; Navrátil, Martin; Buschmann, Claus

    2013-11-01

    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., Platanus x acerifolia Willd., Populus nigra L., Quercus robur L., Tilia cordata Mill. In three cases (beech, ginkgo, and oak), we compared the Chl fluorescence kinetics and photosynthetic rates of blue-shade leaves of the north tree crown receiving only blue sky light but no direct sunlight with that of sun leaves. In these cases, we also determined in detail the pigment composition of all four leaf types. In addition, we determined the quantum irradiance and spectral irradiance of direct sunlight, blue skylight as well as the irradiance in half shade and full shade. The results indicate that sun leaves possess significantly higher mean values for the net CO2 fixation rates P N (7.8-10.7 μmol CO2 m(-2) s(-1) leaf area) and the Chl fluorescence ratio R Fd (3.85-4.46) as compared to shade leaves (mean P N of 2.6-3.8 μmol CO2 m(-2) s(-1) leaf area.; mean R Fd of 1.94-2.56). Sun leaves also exhibit higher mean values for the pigment ratio Chl a/b (3.14-3.31) and considerably lower values for the weight ratio total chlorophylls to total carotenoids, (a + b)/(x + c), (4.07-4.25) as compared to shade leaves (Chl a/b 2.62-2.72) and (a + b)/(x + c) of 5.18-5.54. Blue-shade and half-shade leaves have an intermediate position between sun and shade leaves in all investigated parameters including the ratio F v/F o (maximum quantum yield of PS2 photochemistry) and are significantly different from sun and shade leaves but could not be differentiated from each other. The

  6. [Precautionary maternity leave in Tirol].

    Science.gov (United States)

    Ludescher, K; Baumgartner, E; Roner, A; Brezinka, C

    1998-01-01

    Under Austrian law, precautionary maternity leave is a decree issued by the district public health physician. It forbids a pregnant woman to work and mandates immediate maternity leave. Regular maternity leave for all women employed in all jobs begins at 32 weeks of gestation. Women who work in workplaces deemed dangerous and women with a history of obstetric problems such as premature or growth-retarded babies from previous pregnancies are regularly 'sent' into precautionary maternity leave. The public health physicians of Tirol's nine administrative districts were interviewed and supplied data on precautionary maternity leave from their districts. In 100 women who attended the clinic for pregnancies at risk of the Obstetrics/Gynecology Department of Innsbruck University Hospital and who had already obtained precautionary maternity leave, the medical/administrative procedure was studied in each case and correlated with pregnancy outcome. The town district of Innsbruck and the district that comprises the suburbs of the provincial capital had the highest rates of precautionary maternity leave. The town district of Innsbruck had a rate of 24.3% of all pregnant women (employed and not employed) in precautionary maternity leave in 1997, whereas the whole province of Tirol had 13.4%. More than 80% of decrees for precautionary maternity leave are issued by district public health physicians on the basis of written recommendations from gynecologists. One third of women who are sent into precautionary maternity leave are issued the decree prior to 12 weeks of gestation - mostly cases of multiple pregnancies and women with previous miscarriages. The present system of precautionary maternity leave appears to work in the sense that most working pregnant women with risk factors are correctly identified - with most errors on the side of caution. As the system also helps employers - the employee's pay is paid from the federal family support fund and state insurance once she is in

  7. Penicillium cecidicola, a new species on cynipid insect galls on Quercus pacifica in the western United States

    DEFF Research Database (Denmark)

    Seifert, K.A.; Hoekstra, E.H.; Frisvad, Jens Christian

    2004-01-01

    A synnematous species of Penicillium subgenus Biverticillium was found inside emergence tunnels from insect galls (Cynipidae, Hymenoptera, the so-called gall wasps) on scrub oaks (Quercus pacifica Nixon & C.H. Muller) collected in the western United States. The fungus produces synnemata with white...

  8. Effects of above- and below-ground competition from shrubs on photosynthesis, transpiration and growth in Quercus robur L

    Science.gov (United States)

    Anna M. Jensen; Magnus Lof; Emile S. Gardiner

    2011-01-01

    For a tree seedling to successfully establish in dense shrubbery, it must maintain function under heterogeneous resource availability. We evaluated leaf-level acclimation in photosynthetic capacity, seedling-level transpiration, and seedling morphology and growth to gain an understanding of the effects of above- and below-ground competition on Quercus robur seedlings....

  9. Distribution of Quercus agrifolia mycorrhizae deep within weathered bedrock: a potential mechanism for transport of stored water

    Science.gov (United States)

    M. Bornyasz; R. Graham; M. Allen

    2002-01-01

    In southwestern California, Quercus agrifolia distribution closely matches regions of granitic regolith. High annual evapotranspiration demand and inherent shallow soil conditions lead to a dependence on a deep rooting system and an ability to access water from deep within the regolith. Most of the plant available water in weathered granitic rock is...

  10. Root desiccation and drought stress responses of bareroot Quercus rubra seedlings treated with a hydrophilic polymer root dip

    Science.gov (United States)

    Kent G. Apostol; Douglass F. Jacobs; R. Kasten Dumroese

    2009-01-01

    Root hydrogel, a hydrophilic polymer, has been used to improve transplanting success of bareroot conifer seedlings through effects on water holding capacity. We examined mechanisms by which Terra-sorb Fine Hydrogel reduces damage that occurs when roots of 1-year old, dormant northern red oak (Quercus rubra L.) were subjected to shortterm (1, 3, and 5...

  11. Interactive effects of O3 exposure on California black oak (Quercus kelloggii Newb.) seedlings with and without N amendment

    Science.gov (United States)

    T. Handley; Nancy Grulke

    2008-01-01

    We examined the short-term separate and combined effects of simulated nitrogen (N) deposition (fertilization) and ozone (O3) exposure on California black oak seedlings (Quercus kelloggii Newb.), an ecologically important tree of the San Bernardino Mountains downwind of Los Angeles. Realistic concentrations of O3...

  12. Artificial regeneration of major oak (Quercus) species in the eastern United States - a review of the literature

    Science.gov (United States)

    Daniel C. Dey; Douglass Jacobs; Ken McNabb; Gary W. Miller; V. Baldwin; G. Foster

    2008-01-01

    Although natural regeneration is often the best method for establishing new oak (Quercus spp.) stands, there are increasingly more situations in which high potential for oak regeneration failure dictates the use of artificial regeneration including direct seeding and planting seedlings. Additionally, afforestation planting programs frequently...

  13. Effects of Northern red oak (Quercus rubra L. and sessile oak (Quercus petraea (Mattusch. Liebl. on the forest soil chemical properties

    Directory of Open Access Journals (Sweden)

    Miltner Stanislav

    2016-09-01

    Full Text Available Northern red oak (Quercus rubra L. is one of the most important introduced tree species in the Czech Republic, occupying about 6,000 ha with ca. 900,000 m3 of the standing volume. The presented study aims to evaluate its soil forming effects on natural oak sites. Soil chemistry of the upper soil layers (F+H, Ah, B horizons was studied in three pairs of stands of both species. In each stand, four bulk samples were taken separately for particular horizons, each consisting of 5 soil-borer cores. The soil characteristics analysed were: pH (active and potential, soil adsorption complex characteristics (content of bases, exchangeable cation capacity, base saturation, exchangeable acidity (exchangeable Al and H, total carbon and nitrogen content, and plant available nutrients content (P, K, Ca, Mg. Total macronutrient content (P, K, Ca, Mg was analysed only in holorganic horizons. Results confirmed acidification effects of red oak on the upper forest soil layers such as decreased pH, base content, base saturation, all nutrient contents in total as well as plant-available form and increased soil exchangeable acidity (exchangeable Al in comparison to the sessile oak stands, especially in holorganic horizons and in the uppermost mineral layer (Ah horizon. Northern red oak can be considered as a slightly site-soil degrading species in the studied sites and environmental conditions in comparison to native oak species.

  14. Crecimiento de plántulas y árboles de seis especies de Quercus

    Directory of Open Access Journals (Sweden)

    R. Villar

    2014-01-01

    Full Text Available Los objetivos principales de este trabajo son: a describir algunas características importantes relativas a los rasgos funcionales en plántulas de las especies del género Quercus, b determinar cómo varía la proporción de hoja, tallo y raíz en adultos, y c estimar las tasas de crecimiento relativo(RGR de estas especies para plántulas e individuos adultos. Para ello, usamos los datos de experimentos realizados en plántulas bajo condiciones controladas, del Inventario Forestal Nacional (IFN2 e IFN3 y de las ecuaciones alométricas desarrolladas por Montero et al. (2005. Las especies de Quercus se caracterizan por tener semillas grandes, y las plántulas presentan una baja RGR y área específica foliar (SLA y una alta proporción de raíz (RMR. Uno de los factores más importantes que explican las diferencias en RGR entre las especies de Quercus (tanto en plántulas como en adultos es la diferencia en SLA. Considerando los datos de biomasa de árboles, se observa que la proporción de hoja (LMR y de raíz (RMR disminuye con el tamaño, mientras que la proporción de tallo (SMR aumenta con éste. Si consideramos un árbol medio de 20 cm de diámetro de tronco, los valores de LMR son de sólo 1-5 % y los de SMR van del 50 al 80 %. Considerando los datos del IFN, dentro de cada especie existe una gran variación en RGR. Aun así, cuando se comparan las RGR de las plántulas con los adultos se observa una relación significativa y positiva. Uno de los factores que afectó significativamente a RGR fue el tamaño del árbol, de forma que árboles de mayor tamaño crecían más lentamente.

  15. Characterizing water use strategies of Acer saccharum, Liriodendron tulipifera, and Quercus spp. during a severe drought

    Science.gov (United States)

    Yi, K.; Novick, K. A.; Dragoni, D.; Moore, W.; Roman, D. T.

    2014-12-01

    In many areas, drought is expected to occur more frequently and intensely in the future due to climate change; however, drought effects on ecosystem-scale fluxes in diverse forests will reflect the diversity of water use strategies among the dominant tree species. For three years (2011-2013) that included a severe drought event (in 2012), we measured the sap flow densities along the sapwood profiles (four radial depths: 1, 2, 3, 4 cm) in Acer saccharum, Liriodendron tulipifera, and Quercus spp. using the compensation heat pulse technique at the Morgan-Monroe State Forest (Indiana, USA). Sap flow velocity varies along the radial profile of the stem, and thus characterizing its pattern is important for estimating whole tree sap flow, and for characterizing the extent to which water stress alters the radial pattern of flow. We also focused on the nocturnal sap flow, which may be used to replenish stored water depleted during the daytime, in order to assess the extent to which the three species rely on hydraulic capacitance to cope with water stress. Sap flow densities along the sapwood profile of all three species tended to increase toward the cambium under moderate climate, while the tendency was reversed under severe drought. This shift may indicate greater reliance on stored water in the inner sapwood or cavitation of outer sapwood during the drought. It was also noticeable that Quercus spp. showed lower maximum sap flow density and narrower range (1.5 - 4.6 cm h-1) than other species (A. saccharum: 1.0 - 20.8 cm h-1, L. tulipifera: drought year for A. saccharum (0.140.01 in 2011 and 0.200.01 in 2013 vs. 0.290.01 in 2012) and L. tulipifera (0.140.00 in 2011 and 0.090.01 in 2013 vs. 0.300.01 in 2012), while Quercus spp. didn't show a significant difference between moderate and drought years. This may be due to the replenishment of stored water of A. saccharum and L. tulipifera that was lost during the daytime. These results implied different strategies among the

  16. Hepatoprotective effects of Quercus infectoria gall extract against carbon tetrachloride treated liver injury in rats

    Directory of Open Access Journals (Sweden)

    Gaurav Lodhi

    2012-08-01

    Full Text Available Summary. In the present study, galls of Quercus infectoria possessing potent antioxidant and antiinflammatory properties were evaluated for their hepatoprotective effect against carbon tetrachloride (CCl4 induced hepatotoxicity in rats. Subcutaneous injection of CCl4, administered twice a week, produced a marked elevation in the serum levels of aspartate transaminase (AST, alanine transaminase (ALT and tumor necrosis factor alpha (TNF-α. Histological analysis of the liver of these rats revealed marked necro-inflammatory changes that were associated with increase in the levels of TBARS, PGE2 and catalase and decrease in the levels of glutathione (GSH, superoxide dismutase (SOD and glutathione peroxidase (GPx. Daily oral administration of aqueous ethanolic extract of Quercus infectoria galls at 200, 400 and 600 mg/kg doses produced a dose dependent reduction in the serum levels of liver enzymes and inflammatory mediators and attenuated the necroinflammatory changes in the liver. The QIE treatment also normalized various biochemical parameters of oxidative stress. Our study shows that the hepatoprotective effects of QIE and silymarin were comparable and suggests that QIE could be used as a hepatoprotective agent. Industrial relevance. Research in traditional medicine has lead to the development of many modern medicines. In recent times, focus on plants research has increased all over the world and a large body of evidence has been collected to show immense potential of medicinal plants used in various traditional systems. It is very interesting to note that there is no drug available in the modern system of medicine for treating hepatic disorders; only certain herbal preparations are available to treat this quite vulnerable disease. The situation/background thus explained above warrants for developing a safe, effective and scientifically validated hepatoprotective agent taking lead from traditional medicine, which is affordable for the rural poor

  17. Elemental concentrations in deposited dust on leaves along an urbanization gradient

    Energy Technology Data Exchange (ETDEWEB)

    Simon, Edina, E-mail: edina.simon@gmail.com [Department of Ecology, University of Debrecen, H-4010 Debrecen, P.O. Box 71 (Hungary); Baranyai, Edina [Department of Inorganic and Analytical Chemistry, University of Debrecen, H-4010 Debrecen, P.O. Box 21 (Hungary); Agilent Atomic Spectroscopy Partner Laboratory, University of Debrecen, Egyetem tér 1, H-4032 Debrecen (Hungary); Braun, Mihály [Institute of Nuclear Research of the Hungarian Academy of Sciences, Herteleni Laboratory of Environmental Studies, 4026 Debrecen, Bem tér 18/C (Hungary); Cserháti, Csaba [Department of Solid State Physics, University of Debrecen, H-4010 Debrecen, P.O. Box 2 (Hungary); Fábián, István [Department of Inorganic and Analytical Chemistry, University of Debrecen, H-4010 Debrecen, P.O. Box 21 (Hungary); Tóthmérész, Béla [HAS-UD Biodiversity and Ecosystem Services Research Group, H-4010 Debrecen, P.O. Box 71 (Hungary)

    2014-08-15

    Environmental health is an essential component of the quality of life in modern societies. Monitoring of environmental quality and the assessment of environmental risks are often species based on the elemental concentration of deposited dust. Our result suggested that stomata size and distribution were the most important factors influencing the accumulation of air contaminants in leaves. We found that the leaves' surfaces of Acer negundo and Celtis occidentalis were covered by a large number of trichomes, and these species have proven to be suitable biomonitors for atmospheric pollution difficult; these can be overcome using bioindicator species. Leaves of Padus serotina, Acer campestre, A. negundo, Quercus robur and C. occidentalis were used to assess the amount of deposited dust and the concentration of contaminants in deposited dust in and around the city of Debrecen, Hungary. Samples were collected from an urban, suburban and rural area along an urbanization gradient. The concentrations of Ba, Cu, Fe, Mn, Ni, Pb, S, Sr and Zn were determined in deposited dust using ICP–OES. Scanning electron microscopy (SEM) was used to explore the morphological structure and dust absorbing capacity of leaves. We found significant differences in dust deposition among species, and dust deposition correlated with trichomes' density. Principal component analysis (PCA) also showed a total separation of tree. - Highlights: • Dust is used as indicators of the accumulation of inorganic pollutants. • Scanning EM was used to explore the morphological structure of leaves. • Amount of dust deposited of leaves correlated with trichomes' density. • A. negundo, C. occidentalis and Q. robur are suitable to indicate air contaminants. • A. negundo and C. occidentalis are suitable to decrease the amount of dust in air.

  18. REMINDER Saved Leave Scheme (SLS) : Simplified procedure for the transfer of leave to saved leave accounts

    CERN Multimedia

    HR Division

    2001-01-01

    As part of the process of streamlining procedures, the HR and AS Divisions have jointly developed a system whereby annual and compensatory leave will henceforth be automatically transferred1) to saved leave accounts. Under the provisions of the voluntary saved leave scheme (SLS), a maximum total of 10 days'2)Previously, every person taking part in the scheme has been individually issued with a form for the purposes of requesting the transfer of leave to the leave account and the transfer has then had to be done manually by HR Division. To streamline the procedure, unused leave of all those taking part in the saved leave scheme at the closure of the leave-year accounts will henceforth be transferred automatically to the saved leave account on that date. This simplification is in the interest of all parties concerned. This automatic transfer procedure has a number of advantages for participants in the SLS scheme. First, staff members will no longer have to take any administrative steps. Secondly, the new proced...

  19. LIDAR-based estimation of leaf area index on Holm oak [Quercus ilex L. subsp. ballota (Desf.) Samp.] trees; Aplicacion de imagenes LIDAR para la estimacion de indices de superficie foliar (LAI) en encinas [Quercus ilex L. subsp. Ballota (Desf.) Samp.

    Energy Technology Data Exchange (ETDEWEB)

    Navarro Cerrillo, R. M.; Sanchez de la Orden, M.; Gomez Bonilla, J.; Garcia-Ferrer, A.; Hernandez Clemente, R.; Lanjeri, S.

    2010-07-01

    The aim of this paper was to estimate Leaf Area Index (LAI) of Quercus ilex by calculating the laser-intercepted rate through the forest canopy using LiDAR data. LAI was measured in 40 trees with a hemispheric camera (NIKON Coolpix 4500) and coincided with the acquisition of LIDAR data. The LiDAR-derived LAILIDAR was then estimated by applying a value of the inverse of the coefficient of extinction of 1/K 1.48. The in-field LAI values varied between 1.01 m{sup 2} m{sup -}2 and 1.61 m{sup 2} m{sup -}2. From a comparison of the LiDAR-derived to the field-derived LAI, the coefficients of the determination for the coefficient of extinction of 1.48 was R{sup 2} = 0.60 (RMSE = 0.16) for quadratic and R{sup 2} = 0.62 (RMSE = 0.21) for potential correlations. The change in accuracy was attributed to the density of leaves, the interference by stems, and the vertical number of branches in the forest stands. The LIDAR sensor technique gives a satisfactory result in the obtainment of leaf parameters in Holm oak trees, although its generalisation on field studies depends on its cost and suitability to be applied over large surfaces. (Author) 33 refs.

  20. Distribution Pattern and Conservation Value of Larix potaninii var.macrocarpa Forest in Haba Snow Mountain Reserve%哈巴雪山保护区大果红杉林的分布格局及其保护价值

    Institute of Scientific and Technical Information of China (English)

    袁凤军; 余昌元

    2013-01-01

    Regarding systematic inventory and research on Larix potaninii var. macrocarpa in Haba Snow Mountain Provincial Nature Reserve has not yet been done, while research in other regions is also relatively scarce. Investigation on distribution of Larix potaninii var. macrocarpa in the reserve was made to find out its area, the number of patches, the spatial distribution pattern and community structure. Its conservation value was evaluated from aspects of its naturality, rarity and endemism, biodiversity, vulnerability, its importance in the maintenance of the stability of regional ecosystem, as well as landscape value.%针对哈巴雪山省级自然保护区大果红杉林的系统调查研究尚未有人做过,在其他区域的调查研究也相对较少的状况.对保护区内分布的大果红杉林进行调查,摸清其面积、斑块数量、空间分布格局和群落结构组成等情况,从自然性、稀有特有性、生物多样性、脆弱性、在维护区域生态系统稳定中的重要性、景观价值等方面对其保护价值进行了评价.

  1. [Age structure and dynamics of Quercus wutaishanica population in Lingkong Mountain of Shanxi Province, China].

    Science.gov (United States)

    Zhang, Jie; Shangguan, Tie-Liang; Duan, Yi-Hao; Guo, Wei; Liu, Wei-Hua; Guo, Dong-Gang

    2014-11-01

    Using the plant survivorship theory, the age structure, and the relationship between tree height and diameter (DBH) of Quercus wutaishanica population in Lingkong Mountain were analyzed, and the static life table was compiled and the survival curve plotted. The shuttle shape in age structure of Q. wutaishanica population suggested its temporal stability. The linear regression significantly fitted the positive correlation between tree height and DBH. The maximal life expectancy was observed among the trees beyond the age of the highest mortality and coincided with the lowest point of mortality density, suggesting the strong vitality of the seedlings and young trees that survived in the natural selection and intraspecific competition. The population stability of the Q. wutaishanica population was characterized by the Deevey-II of the survival curve. The dynamic pattern was characterized by the recession in the early phase, growth in the intermediate phase, and stability in the latter phase.

  2. Rotation planar extraction and rotation planar chromatography of oak (Quercus robur L.) bark.

    Science.gov (United States)

    Vovk, Irena; Simonovska, Breda; Andrensek, Samo; Vuorela, Heikki; Vuorela, Pia

    2003-04-04

    The versatile novel instrument for rotation planar extraction and rotation planar chromatography was exploited for the investigation of oak bark (Quercus robur L.). The same instrument enabled extraction of the bark, analytical proof of (+)-catechin directly in the crude extract and also its fractionation. Additionally, epimeric flavan-3-ols, (+)-catechin and (-)-epicatechin were separated by analytical ultra-micro rotation planar chromatography on cellulose plates with pure water as developing solvent. A comparison of the extraction of oak bark with 80% aqueous methanol by rotation planar extraction and medium pressure solid-liquid extraction was carried out and both techniques were shown to be suitable for the efficient extraction of oak bark. The raw extracts and fractions on thin-layer chromatography showed many compounds that possessed antioxidant activity after spraying with 1,1-diphenyl-2-picrylhydrazyl. Rotation planar fractionation of 840 mg of crude oak bark extract on silica gel gave 6.7 mg of pure (+)-catechin in one run.

  3. Dalechampii oak (Quercus dalechampii Ten., an important host plant for folivorous lepidoptera larvae

    Directory of Open Access Journals (Sweden)

    Kulfan, M.

    2013-06-01

    Full Text Available We conducted a structured analysis of lepidoptera larvae taxocenoses living in leaf bearing crowns of Dalechampii oak (Quercus dalechampii Ten. in nine study plots in the Malé Karpaty Mountains (Central Europe. The differences between lepidoptera taxocenoses in individual oak stands were analyzed. A total of 96 species and 2,140 individuals were found. Species abundance peaked in May, while number of species and species diversity reached the highest values from April to May and from April to June, respectively. Abundance showed two notable peaks in flush feeders and in late summer feeders. Lepidoptera taxocenosis in the study plot Horný háj (isolated forest, high density of ants differed significantly from all other taxocenoses according to Sörensen’s index of species similarity, species diversity, analysis of similarity on the basis of permutation and pairwise tests (ANOSIM, seasonal variability of species composition, and NMDS ordination.

  4. Larvicidal activity of oak Quercus infectoria Oliv. (Fagaceae) gall extracts against Anopheles stephensi Liston.

    Science.gov (United States)

    Aivazi, Ali-Ashraf; Vijayan, V A

    2009-06-01

    There is a growing interest in the use of botanical insecticides to reduce the use of synthetic pesticides in order to avoid environmental side effects. Anopheles stephensi is the primary vector of urban malaria, an endemic disease in India. So, an effort to assay An. stephensi larvae with gall extracts of Quercus infectoria was made under laboratory conditions at Mysore. Ethyl-acetate extract was found to be the most effective of all the five extracts tested for larvicidal activity against the fourth instar larvae, with LC(50) of 116.92 ppm followed by gallotannin, n-butanol, acetone, and methanol with LC(50) values of 124.62, 174.76, 299.26, and 364.61 ppm, respectively. The efficacy in killing mosquito larvae may make this plant promising for the development of new botanical larvicide.

  5. QUERCUS ROBUR, Q. CERRIS AND Q. PETRAEA AS HOT SPOTS OF BIODIVERSITY

    Directory of Open Access Journals (Sweden)

    Ecaterina FODOR

    2016-12-01

    Full Text Available Three different bipartite networks (pathogenic, ectomycorrhizal and galling insects established by Quercus robur L., Q. cerris L. and Q. petraea (Matt. Liebl. were merged in order to investigate the topological properties of the complex network, shading light on how biodiversity was organized through complex interactions. The complex network contains 290 species – 137 are pathogens (parasitic interaction, 72 are mycorrhizal fungi (mutualists and 81 species of galling insects (herbivores. Most relevant network descriptors, connectivity, nestedness and modularity were analyzed. The main network and subnetworks displayed different behaviors in terms of topological properties, three of four networks showing significant modularity (galling insects network was marginally significant in what regards modularity. High connectivity and different degrees of nestedness characterized all networks. Clustering and Non Metric Multidimensional scaling refined the information provided by network analysis showing that networks occupy distant positions in ordination space and there are differences in terms of resemblance patterns.

  6. PHYTOGEOGRAPHY OF QUERCUS SUBER L. IN LAZIO (CENTRAL ITALY: A CAUSALISTIC APPROACH

    Directory of Open Access Journals (Sweden)

    B. SCHIRONE

    2008-01-01

    Full Text Available A descriptive statistical approach to the causalistic distribution of Quercus suber in Lazio (Central Italy, based on presence/absence data and mean values of an array of environmental variables standardized on a geographical 6,9 x 5,5 Km grid, shows that only temperature, precipitation, elevation and slope are significant. At this scale, soil conditions and aspect are apparently no limiting factors to the colonization ability of the species. A simulated potential range, based on this parameterization, identifies a larger area than the one occupied by the species today. It suggests that competition and human disturbance might account for the large gaps and discontinuities in the real range. Since inland disjunct outposts still lie either outside or at the boundary of this simulated range, their establishment is likely to have originated under macroclimatic conditions different from the present day ones.

  7. PHYTOGEOGRAPHY OF QUERCUS SUBER L. IN LAZIO (CENTRAL ITALY: A CAUSALISTIC APPROACH

    Directory of Open Access Journals (Sweden)

    F. SPADA

    2008-04-01

    Full Text Available A descriptive statistical approach to the causalistic distribution of Quercus suber in Lazio (Central Italy, based on presence/absence data and mean values of an array of environmental variables standardized on a geographical 6,9 x 5,5 Km grid, shows that only temperature, precipitation, elevation and slope are significant. At this scale, soil conditions and aspect are apparently no limiting factors to the colonization ability of the species. A simulated potential range, based on this parameterization, identifies a larger area than the one occupied by the species today. It suggests that competition and human disturbance might account for the large gaps and discontinuities in the real range. Since inland disjunct outposts still lie either outside or at the boundary of this simulated range, their establishment is likely to have originated under macroclimatic conditions different from the present day ones.

  8. Epigenetic marks in the mature pollen of Quercus suber L. (Fagaceae).

    Science.gov (United States)

    Ribeiro, Teresa; Viegas, Wanda; Morais-Cecílio, Leonor

    2009-03-01

    We have analysed the distribution of epigenetic marks for histone modifications at lysine residues H3 and H4, and DNA methylation, in the nuclei of mature pollen cells of the Angiosperm tree Quercus suber; a monoecious wind pollinated species with a protandrous system, and a long post-pollination period. The ultrasonic treatment developed for the isolation of pollen nuclei proved to be a fast and reliable method, preventing the interference of cell wall autofluorescence in the in situ immunolabelling assays. In contrast with previous studies on herbaceous species with short progamic phases, our results are consistent with a high level of silent (5-mC and H3K9me2) epigenetic marks on chromatin of the generative nucleus, and the prevalence of active marks (H3K9me3 and H4Kac) in the vegetative nucleus. The findings are discussed in terms of the pollination/fertilization timing strategy adopted by this plant species.

  9. Genetic transformation of selected mature cork oak (Quercus suber L.) trees.

    Science.gov (United States)

    Alvarez, R; Alonso, P; Cortizo, M; Celestino, C; Hernández, I; Toribio, M; Ordás, R J

    2004-10-01

    A transformation system for selected mature cork oak (Quercus suber L.) trees using Agrobacterium tumefaciens has been established. Embryos obtained from recurrent proliferating embryogenic masses were inoculated with A. tumefaciens strains EHA105, LBA4404 or AGL1 harbouring the plasmid pBINUbiGUSint [carrying the neomycin phosphotransferase II (nptII) and beta-glucuronidase (uidA) genes]. The highest transformation efficiency (4%) was obtained when freshly isolated explants were inoculated with A. tumefaciens strain AGL1. Evidence of stable transgene integration was obtained by PCR for the nptII and uidA genes, Southern blotting and expression of the uidA gene. The transgenic embryos were germinated and successfully transferred to soil.

  10. 5 CFR 630.1003 - Establishing leave banks and leave bank boards.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Establishing leave banks and leave bank... REGULATIONS ABSENCE AND LEAVE Voluntary Leave Bank Program § 630.1003 Establishing leave banks and leave bank boards. (a) Each agency that participates in the voluntary leave bank program shall, in accordance...

  11. Symptoms of the naturalisation of the Turkey oak (Quercus cerris L. in Polish forests

    Directory of Open Access Journals (Sweden)

    Danielewicz Władysław

    2016-09-01

    Full Text Available The Turkey oak (Quercus cerris L., the natural range of which embraces southern Europe and Asia Minor, belongs to trees rarely introduced into Polish forests. Tree stands where it appears, established before the Second World War, can be found in some 20 localities, mostly in the western part of the country. Because this species is capable of a natural renewal in a woodland environment, a research was made to find in what conditions and how far it undergoes spontaneous naturalisation. Three study sites were chosen in the forests of central Wielkopolska. An inventory was made of mature stands of the Turkey oak and its generative renewal. Plant communities in which the young generation of Q. cerris usually appears were characterised. It was found that self-sown seedlings of this species grew at a distance of up to 2,500 m from parent trees. The highest number and the greatest density of specimens of the secondary generation of the Turkey oak were found at ‘Racot’, which is a 100-hectare, mid-field woodland island where mesotrophic habitats predominate and where about 50% of the area is occupied by communities with manmade pine tree stands. At all sites, Q. cerris penetrates primarily this type of deformed phytocoenoses, developing mostly on former farmland. It has become a permanent component of the underbrush and undergrowth in them, and in some places, it also makes up the tree layer. It was observed that in the study area, it penetrated the woodland environment much more effectively than Quercus rubra, considered an invasive species. The expansion of the Turkey oak in several of the examined localities can be regarded as a basic manifestation of its naturalisation in places where there are phytocoenoses with pine stands in broad-leaf forest habitats in the neighbourhood of parent trees.

  12. Nomenclatura popular de Quercus (Fagaceae: en los valles meridionales de Cantabria (España

    Directory of Open Access Journals (Sweden)

    Pardo de Santayana, Manuel

    2002-06-01

    Full Text Available A survey of the Ethnotaxonomy and Ethnonomenclature of southern Cantabria Quercus (Q- faginea subsp. faginea, Q. ilex subsp. ilex, Q. petraea, Q. pyrenaica, Q. robur is presented. An extensive vocabulary associated with these popular species has been compiled. The analysis of this lexicón shows the richness and complexity of folk plant taxonomy and nomenclature. In total 28 vernacular ñames, which are different forms of 12 principal lexemes, have been compiled. Maps with the geographical distribution of the ñames let us delimit lingüistical áreas. An analysis of this rich lexicón is also presented. The meaning of the ñames, often polisemic, theiretymologies and geographical distribution is studied.Se presenta un estudio sobre la etnotaxonomía y etnonomenclatura de los Quercus (Q. faginea subsp. faginea, Q. ilex subsp. ilex, Q. petraea, Q. pyrenaica, Q. robar que viven en el S de Cantabria. Se ha desarrollado un abundante léxico en tomo a estas especies tan cotidianas, que sirve de ejemplo para estudiar la complejidad y riqueza de la nomenclatura popular. Se han recopilado 28 nombres vernáculos, variantes de 12 lexemas principales. Se han realizado mapas de distribución de los nombres recopilados que permiten delimitar zonas lingüísticas. Además se presenta un análisis de este rico léxico en el que se hace hincapié en su significado, muchas veces polisémico, etimología y distribución geográfica.

  13. Considerations for Sustainable Biomass Production in Quercus-Dominated Forest Ecosystems

    Science.gov (United States)

    Bruckman, Viktor; Yan, Shuai; Hochbichler, Eduard

    2013-04-01

    Our current energy system is mainly based on carbon (C) intensive metabolisms, resulting in great effects on the earth's biosphere. The majority of the energy sources are fossil (crude oil, coal, natural gas) and release CO2 in the combustion (oxidation) process which takes place during utilization of the energy. C released to the atmosphere was once sequestered by biomass over a time span of millions of years and is now being released back into the atmosphere within a period of just decades. In the context of green and CO2 neutral Energy, there is an on-going debate regarding the potentials of obtaining biomass from forests on multiple scales, from stand to international levels. Especially in the context of energy, it is highlighted that biomass is an entirely CO2 neutral feedstock since the carbon stored in wood originates from the atmospheric CO2 pool and it was taken up during plant growth. It needs systems approaches in order to justify this statement and ensure sustainability covering the whole life-cycle from biomass production to (bio)energy consumption. There are a number of Quercus woodland management systems focussing solely on woody biomass production for energetic utilization or a combination with traditional forestry and high quality timber production for trades and industry. They have often developed regionally as a consequence of specific demands and local production capacities, which are mainly driven by environmental factors such as climate and soil properties. We assessed the nutritional status of a common Quercus-dominated forest ecosystem in northern Austria, where we compared biomass- with belowground C and nutrient pools in order to identify potential site limits if the management shifts towards systems with a higher level of nutrient extraction. Heterogeneity of soils, and soil processes are considered, as well as other, growth-limiting factors (e.g. precipitation) and species-specific metabolisms and element translocation.

  14. High Genetic Differentiation among European White Oak Species (Quercus spp. at a Dehydrin Gene

    Directory of Open Access Journals (Sweden)

    Iacob CRĂCIUNESC

    2015-12-01

    Full Text Available Dehydryn genes are involved in plant response to environmental stress and may be useful to examine functional diversity in relation to adaptive variation. Recently, a dehydrin gene (DHN3 was isolated in Quercus petraea and showed little differentiation between populations of the same species in an altitudinal transect. In the present study, inter- and intraspecific differentiation patterns in closely related and interfertile oaks were investigated for the first time at the DHN3 locus. A four-oak-species stand (Quercus frainetto Ten., Q. petraea (Matt. Liebl., Q. pubescens Willd., Q. robur L. and two populations for each of five white oak species (Q. frainetto Ten., Q. petraea (Matt. Liebl., Q. pubescens Willd., Q. robur L. and Q. pedunculiflora K. Koch were analyzed. Three alleles shared by all five oak species were observed. However, only two alleles were present in each population, but with different frequencies according to the species. At population level, all interspecific pairs of populations showed significant differentiation, except for pure Q. robur and Q. pedunculiflora populations. In contrast, no significant differentiation (p > 0.05 was found among conspecific populations. The DHN3 locus proved to be very useful to differentiate Q. frainetto and Q. pubescens from Q. pedunculiflora (FST = 0.914 and 0.660, respectively and Q. robur (FST = 0.858 and 0.633, respectively. As expected, the lowest level of differentiation was detected between the most closely related species, Q. robur and Q. pedunculiflora (FST = 0.020. Our results suggest that DHN3 can be an important genetic marker for differentiating among European white oak species.

  15. Comparison of Characteristic of Water Balance between Evergreen Coniferous and Deciduous Broad-leaved Forests

    Science.gov (United States)

    Hisada, Shigeta; Senge, Masateru; Ito, Kengo; Maruyama, Toshisuke

    Hydrological observation was carried out at two basins occupied mainly by evergreen coniferous forest of Chamaecyparis obtusa and deciduous broad-leaved forest of Quercus crispula in order to clarify the influences of different forest type on water balance. The analysis of short-time period water-budget method showed that the evapotranspiration of coniferous forest was more than broad-leaved one. By calculating transpiration from Priestley-Taylor equation, intercepted evaporation was separated from evapotranspiration. The result of comparison of intercepted evaporation between two basin was that intercepted evaporation of coniferous basin was more than that of broad-leaved basin. From separating total runoff into direct and base flow components; it was shown that there was no difference in direct runoff of two basins, so the differences of total runoff of two basins were caused due to the difference of base flow. From the above analysis of water balance components, it is clarified that the different forest type influences the amount of intercepted evaporation and base flow.

  16. Antibacterial effects of Quercus Brantii fruits and Stachys lavandulifolia methanol extracts on imipenemase-type metallo-beta lactamase-producing Pseudomonas aeruginosa

    National Research Council Canada - National Science Library

    F. Shahi; A. Hashemi; Kh. Abdolmaleki; Z. Shahi; Sh. Amraei; H. Goudarzi; F. Fallah; S. Khoshnood

    2017-01-01

    .... The aim of the present study was to evaluate the antibacterial activity of Stachys lavandulifolia and Quercus brantii on the IMP-type metallo-beta-lactamase-producing Pseudomonas aeruginosa. Methods...

  17. Leaves of Absence. School Law Summary.

    Science.gov (United States)

    National Education Association, Washington, DC. Research Div.

    This report contains State-by-State statutory summaries on three types of leaves of absence relating to teachers -- sick leave, maternity leave, and sabbatical leave. Only State laws that have specific reference to one of these three types of leaves of absence are included. Not included are those statutes granting boards of education the general…

  18. Key Obama officials leave administration

    Science.gov (United States)

    Showstack, Randy

    2013-01-01

    Secretary of the Interior Ken Salazar is one of the latest members of the Obama administration to announce that he is leaving his position near the start of President Obama's second term in office. Salazar, who has served as interior secretary since January 2009, intends to leave the department by the end of March, the department noted on 16 January. Salazar joins a number of other key officials who are planning to leave the administration. They include Environmental Protection Agency administrator Lisa Jackson, National Oceanic and Atmospheric Administration administrator Jane Lubchenco, and U.S. Geological Survey director Marcia McNutt.

  19. New statement of leave format

    CERN Multimedia

    HR Department

    2009-01-01

    Following the communication of the Standing Concertation Committee published in Weekly Bulletin No. 18-19 of 27 April 2009, the current statement of leave on monthly pay slips has been replaced with the EDH Leave Transactions report that displays the up-to-date situation of individual leave balances at all times. The report is available on EDH. Additionally, the layout of the pay slip has been modernised. The new version of the pay slip will be send out from September 2009 onwards. Finance and Purchasing Department, Personnel Accounting Human Resources Department, Organisation and Procedures General Infrastructure Services Department, Administrative Information Services

  20. 2-DE proteomics analysis of drought treated seedlings of Quercus ilex supports a root active strategy for metabolic adaptation in response to water shortage.

    Science.gov (United States)

    Simova-Stoilova, Lyudmila P; Romero-Rodríguez, Maria C; Sánchez-Lucas, Rosa; Navarro-Cerrillo, Rafael M; Medina-Aunon, J Alberto; Jorrín-Novo, Jesús V

    2015-01-01

    Holm oak is a dominant tree in the western Mediterranean region. Despite being well adapted to dry hot climate, drought is the main cause of mortality post-transplanting in reforestation programs. An active response to drought is critical for tree establishment and survival. Applying a gel-based proteomic approach, dynamic changes in root proteins of drought treated Quercus ilex subsp. Ballota [Desf.] Samp. seedlings were followed. Water stress was applied on 20 day-old holm oak plantlets by water limitation for a period of 10 and 20 days, each followed by 10 days of recovery. Stress was monitored by changes in water status, plant growth, and electrolyte leakage. Contrary to leaves, holm oak roots responded readily to water shortage at physiological level by growth inhibition, changes in water status and membrane stability. Root proteins were extracted using trichloroacetate/acetone/phenol protocol and separated by two-dimensional electrophoresis. Coomassie colloidal stained gel images were analyzed and spot intensity data subjected to multivariate statistical analysis. Selected consistent spots in three biological replicas, presenting significant changes under stress, were subjected to MALDI-TOF mass spectrometry (peptide mass fingerprinting and MS/MS). For protein identification, combined search was performed with MASCOT search engine over NCBInr Viridiplantae and Uniprot databases. Data are available via ProteomeXchange with identifier PXD002484. Identified proteins were classified into functional groups: metabolism, protein biosynthesis and proteolysis, defense against biotic stress, cellular protection against abiotic stress, intracellular transport. Several enzymes of the carbohydrate metabolism decreased in abundance in roots under drought stress while some related to ATP synthesis and secondary metabolism increased. Results point at active metabolic adjustment and mobilization of the defense system in roots to actively counteract drought stress.

  1. 2-DE proteomics analysis of drought treated seedlings of Quercus ilex supports a root active strategy for metabolic adaptation in response to water shortage

    Directory of Open Access Journals (Sweden)

    Lyudmila Petrova Simova-Stoilova

    2015-08-01

    Full Text Available Holm oak is a dominant tree in the western Mediterranean region. Despite being well adapted to dry hot climate, drought is the main cause of mortality post-transplanting in reforestation programs. An active response to drought is critical for tree establishment and survival. Applying a gel-based proteomic approach, the dynamic changes in root proteins of drought treated Quercus ilex subsp. Ballota [Desf.] Samp. seedlings were followed. Water stress was applied on 20 day-old holm oak plantlets by water limitation for a period of 10 and 20 days, each followed by 10 days of recovery. Stress was monitored by changes in water status, plant growth and electrolyte leakage. Contrary to leaves, holm oak roots responded readily to water shortage at physiological level by growth inhibition, changes in water status and membrane stability. Root proteins were extracted using trichloroacetate/acetone/phenol protocol and subjected to two-dimensional electrophoresis. Coomassie colloidal stained gel images were analysed and spot intensity data subjected to multivariate statistical analysis. Selected consistent spots in the three biological replicas, presenting significant changes under stress, were subjected to MALDI-TOF mass spectrometry (peptide mass fingerprinting and MS/MS. For protein identification, combined search was performed with MASCOT search engine over NCBInr Viridiplantae and Uniprot databases. Data are available via ProteomeXchange with identifier PXD002484. Identified proteins were classified into functional groups: metabolism, protein biosynthesis and proteolysis, defence against biotic stress, cellular protection against abiotic stress, intracellular transport. Several enzymes of the carbohydrate metabolism decreased in abundance in roots under drought stress while some related to ATP synthesis and secondary metabolism increased. Results point at active metabolic adjustment and mobilization of the defence system in roots to actively counteract

  2. Biomass, Carbon and Nutrient Storage in a 30-Year-Old Chinese Cork Oak (Quercus Variabilis Forest on the South Slope of the Qinling Mountains, China

    Directory of Open Access Journals (Sweden)

    Yang Cao

    2015-04-01

    Full Text Available Chinese cork oak (Quercus variabilis forests are protected on a large-scale under the Natural Forest Protection (NFP program in China to improve the ecological environment. However, information about carbon (C storage to increase C sequestration and sustainable management is lacking. Biomass, C, nitrogen (N and phosphorus (P storage of trees, shrubs, herb, litter and soil (0–100 cm were determined from destructive tree sampling and plot level investigation in approximately 30-year old Chinese cork oak forests on the south slope of the Qinling Mountains. There was no significant difference in tree components’ biomass estimation, with the exception of roots, among the available allometric equations developed from this study site and other previous study sites. Leaves had the highest C, N and P concentrations among tree components and stems were the major compartments for tree biomass, C, N and P storage. In contrast to finding no difference in N concentrations along the whole soil profile, higher C and P concentrations were observed in the upper 0–10 cm of soil than in the deeper soil layers. The ecosystem C, N, and P storage was 163.76, 18.54 and 2.50 t ha−1, respectively. Soil (0–100 cm contained the largest amount of C, N and P storage, accounting for 61.76%, 92.78% and 99.72% of the total ecosystem, followed by 36.14%, 6.03% and 0.23% for trees, and 2.10%, 1.19% and 0.03% for shrubs, herbs and litter, respectively. The equations accurately estimate ecosystem biomass, and the knowledge of the distribution of C, N and P storage will contribute to increased C sequestration and sustainable management of Chinese cork oak forests under the NFP program.

  3. Removal of acorns of the alien oak Quercus rubra on the ground by scatter-hoarding animals in Belgian forests

    Directory of Open Access Journals (Sweden)

    Merceron, NR.

    2017-01-01

    Full Text Available Description of the subject. Quercus rubra L. is considered an invasive species in several European countries. However, little is known about its dispersal in the introduced range. Objectives. We investigated the significance of animal dispersal of Q. rubra acorns on the ground by vertebrates in its introduced range, and identified the animal species involved. Method. During two consecutive autumns, the removal of acorns from Q. rubra and from a native oak was assessed weekly in forest sites in Belgium. We used automated detection camera traps to identify the animals that removed acorns. Results. Quercus rubra acorns were removed by wood mice (Apodemus sylvaticus L., red squirrels (Sciurus vulgaris L., rats (Rattus sp., and wild boars (Sus scrofa L.. The two former are scatter-hoarding rodents and can be considered potential dispersers. Conclusions. Dispersal of Q. rubra acorns in Western Europe by scatter-hoarding animals may help the species increasingly colonize forest ecosystems.

  4. Phytogeography of Quercus subg.Cyclobalanopsis%青冈亚属植物的地理分布

    Institute of Scientific and Technical Information of China (English)

    罗艳; 周浙昆

    2001-01-01

    Quercus subg. Cyclobalanopsis(Oerst.) Schneid. is an importantconstituent of broad leaved evergreen forests in subtropical and tropical regions of Asia. It contains 122 species distrbuted primarily within the Tropical Asia (Indo-Malaysia) phytogeographic province. A number of species were analyzed to develop a biogeographical and phytogenetic context for the diversity within subg. Cyclobalanopsis. Southern China and the north northern part of the Indo-Chine Peninsula show the highest species diversity and may be considered the two centers of diversity. A number of species in Malaysia were observed to have some plesiomorphic characters, and this region may be considered the center of origin and a key area of endemism. On the island of Borneo, the area of Kalimantan is richest in endemic species and the fossil species record resemble this fact. In contrast, the endemic species from Hainan and Taiwan are more derived. The endemic species of Yunnan represent a mixture of neoendemics and paleoendemics. The formation of patterns of endemism in Cyclobalanopsis is due primarily to geographical isolation and the complex history of climatic and geological changes. Also we have discussed vicariance of Cyclobalanopsis: Q.glauca & Q.schottkyana, Q.gilva & Q.delavayi, Q.sessifolia & Q.augustinii are vicariance species between Sino-Japan and Sino-Himalaya.%对壳斗科青冈亚属(Quercussubg.Cyclobalanopsis)植物分布区内各地区的分布作了分析和统计。通过分析,认为中国南部、西南部和中南半岛北部,即印度支那植物地区,是青冈亚属植物地理分布的分布区中心。基于其形态、现代分布和地史资料,马来西亚地区分布有许多性状较原始的类群,是青冈亚属原始类群的保存中心。青冈亚属植物中有许多地区性特有种,它们的分布区很狭窄,集中分布在加里曼丹、台湾、海南和云南东南部,其产生的原因主要是地理隔离,如海峡、高山等,

  5. Drought influence on carbon and water cycling in a Mediterranean Quercus suber L. woodland during the drought year 2012

    Science.gov (United States)

    Piayda, Arndt; Dubbert, Maren; Rebmann, Corinna; Kolle, Olaf; Silva, Filipe Costa e.; Correia, Alexandra; Santos Pereira, Joao; Werner, Christiane; Cuntz, Matthias

    2014-05-01

    Savannah-type ecosystems account for 26-30% of the global gross primary production with water being one of the major driving factors. In Europe, savannah-type woodlands cover an area of about 2-2.5 million ha on the Iberian Peninsula. The recent past has shown there a significant decrease of precipitation in winter and spring as well as a decrease of total annual precipitation. Hence, strong effects on local water balance and carbon sink strength have been reported due to these changes in the precipitation regime. The objective of this study is to quantify changes in the water balance, gross primary productivity and carbon sink strength of a typical Portuguese savannah-type woodland (montado) under the changed precipitation pattern of the drought year 2012 compared to the wet year 2011. The physiological response of the dominant tree species Quercus suber (L.) is evaluated, employing combined photosynthesis and stomatal conductance modelling. Precipitation effectiveness ratio increased up to 122% in the dry year 2012 due to ground water access of the Q. suber trees leaving no water for ground water replenishment. By the lack of water in the upper soil and deep ground water reservoirs, the understorey and overstorey gross primary productions were reduced by 53% and 28% in 2012 compared to 2011, respectively, due to the late onset of the autumn rains in 2011 and an additional severe winter/spring drought. However, on an annual basis, the ecosystem was a carbon sink in both years, with a 61% reduced sink strength in the dry year 2012 compared to the wet 2011. Applying a combined photosynthesis and stomatal conductance model, best model fit to gross primary productivity and transpiration of Q. suber trees could be achieved keeping apparent maximum carboxylation rate V c,max as well as stomatal conductivity parameter m and vapor pressure deficit sensitivity parameter D0 of the stomatal conductance formulation variable. The Q. suber trees showed 20% reduced stomatal

  6. Early markers are present in both embryogenesis pathways from microspores and immature zygotic embryos in cork oak, Quercus suber L

    OpenAIRE

    2014-01-01

    Background: In Quercus suber, cork oak, a Mediterranean forest tree of economic and social interest, rapid production of isogenic lines and clonal propagation of elite genotypes have been achieved by developing in vitro embryogenesis from microspores and zygotic embryos respectively. Despite its high potential in tree breeding strategies, due to their recalcitrancy, the efficiency of embryogenesis in vitro systems in many woody species is still very low since factors responsible for embryogen...

  7. The ecosystem of the Yahudia Nature Reserve with emphasis on dynamics of germination and development of Quercus ithaburensis decne

    OpenAIRE

    Kaplan, Y

    1984-01-01

    6 main subjects connected with the ecology of the Yahudia Forest Reserve are discussed in this paper, following a general survey of the history of nature conservation in Israel against the background of the neighbouring countries. We have described the physical and historical background of the Yahudia Forest; the inventory of vertebrates; the inventory of vegetation, analysing composition and mapping; described and researched Quercus ithaburensis from various aspects, wit...

  8. The ecosystem of the Yahudia Nature Reserve with emphasis on dynamics of germination and development of Quercus ithaburensis Decne

    OpenAIRE

    Kaplan, Y.

    1984-01-01

    6 main subjects connected with the ecology of the Yahudia Forest Reserve are discussed in this paper, following a general survey of the history of nature conservation in Israel against the background of the neighbouring countries. We have described the physical and historical background of the Yahudia Forest; the inventory of vertebrates; the inventory of vegetation, analysing composition and mapping; described and researched Quercus ithaburensis from various aspects, with emphasis on phenolo...

  9. First Report of the Winter Moth Operophtera brumata on Quercus canariensis and Q. afares in North West of Tunisia

    OpenAIRE

    Yaussra Mannai; Olfa Ezzine; Said Nouira; Mohamed Lahbib Ben Jamâa

    2015-01-01

    Operophtera brumata is a newly detected moth in Tunisia. It is considered the most important leaffeeding pest infesting fruit trees and deciduous forests in northern Europe. A recent outbreak of the winter moths was observed between 2009 and 2014 in oak forest in the North West of Tunisia with a peak density in 2010-2011. O. brumata was observed on totally defoliated Quercus canariensis and Q. afares. In this paper, we present a first report of this pest.

  10. 5 CFR 630.1204 - Intermittent leave or reduced leave schedule.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Intermittent leave or reduced leave schedule. 630.1204 Section 630.1204 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS ABSENCE AND LEAVE Family and Medical Leave § 630.1204 Intermittent leave or reduced leave...

  11. 5 CFR 630.404 - Use of sick leave during annual leave.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Use of sick leave during annual leave. 630.404 Section 630.404 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS ABSENCE AND LEAVE Sick Leave § 630.404 Use of sick leave during annual leave. Subject to §...

  12. Propagación in vitro de encinos mexicanos (Quercus spp.

    Directory of Open Access Journals (Sweden)

    Jose Silvestre Delgadillo-Díaz de León

    2015-08-01

    Full Text Available Con el fin de ofrecer una alternativa a los sistemas convencionales de propagación, se desarrolló un protocolo para la multiplicación in vitro de cuatro especies mexicanas deQuercus, las cuales son explotadas para la producción de madera y carbón y están actualmente amenazadas. Se describe la inducción de brotes múltiples a partir de embriones cigóticos deQuercus castanea,Q. eduardii,Q. resinosayQ. rugosacultivados en medio de Murashige y Skoo-genriquecido con 6-bencilaminopurina (BA o cinetina. Los resultados mostraron que ambas citocininas afectaron la regeneración de brotes, donde la BA mostró la mayor efi ciencia. La mayor frecuencia de proliferación de brotes se observó enQ. castaneayQ. eduardii(91.7%, dando promedios de 6.3 y 6.5 brotes por explante al utilizar 3.0 y 4.0 mg l-1de BA, respectivamente. ParaQ. resinosa, la mejor respuesta fue obtenida con BA a 3.0 mg l-1produciendo 3.8 brotes por explante. Finalmente,Q. rugosaprodujo 3.6 brotes por explante con 1.0 mg l-1de BA. Los brotes fueron separados de las plántulas y transferidos a un medio basal a la mitad de su concentración enriquecido con 10.0 mg l-1de ac. indolbutírico por dos a cinco días, y luego transferidos a medio a la mitad de su concentración para su enraizamiento. Bajo estas condiciones, el 100, 100, 66.7 y 83.3% de los brotes deQ. castanea,Q. eduardii,Q. resinosayQ. rugosageneraron raíces, respectivamente. Las plántulas fueron aclimatadas a suelo en condiciones de invernadero de manera exitosa con frecuencias de sobrevivencia de 80% paraQ. castanea, 83.3% paraQ. eduardii, 73.3% paraQ. resinosa, y 70.0% paraQ. rugosa. Este método de propagación in vitro puede contribuir a la producción de plantas con fines de reforestación apoyando así la conservación y uso racional de estas especies.

  13. Differences in photosynthesis and isoprene emission in post oak (Quercus stellata) and sweetgum (Liquidambar styraciflua) trees along an urban-to-rural gradient in Texas

    Science.gov (United States)

    Crossett, C.; Lahr, E.; Haas, G.; Schade, G. W.

    2014-12-01

    Many plants produce isoprene, a volatile organic compound that can mitigate damage to photosynthetic systems during short- or long-term increases in leaf temperature. After its production within leaves, isoprene is emitted to the atmosphere and influences regional atmospheric chemistry. Here, we use an urban-to-rural gradient to explore future effects of climate change on tree eco-physiology and feedbacks to atmospheric chemistry. Urban areas mimic many of the conditions expected to occur in the future; in particular, cities have warmer temperatures due to the urban heat island (UHI) effect, and less water availability relative to rural areas. Along a 90 km urban-to-rural gradient, we measured photosynthesis and isoprene emission from trees at three sites in eastern Texas: Houston (urban), The Woodlands (suburban) and Sam Houston National Forest (rural). Isoprene emission from post oak (Quercus stellata) was higher in Houston than the other sites, and when leaf temperatures were increased above ambient conditions, trees produced more isoprene. Leaves produced more isoprene at high leaf temperatures in early summer than in late summer, suggesting gradual acclimation of photosynthetic processes over the course of the summer. We also found that sweetgum (Liquidambar styraciflua) emitted more isoprene than post oak, but when leaf temperatures were increased, isoprene emission was exhausted more quickly in sweetgum relative to post oak. At the same time, post oak maintained higher levels of photosynthesis seasonally and during short-term temperature increases. Both post oak and sweetgum are significant isoprene emitters and represent approximately two and four percent crown cover in the United States, respectively. Our results suggest that in a warming climate, we can expect trees to produce more isoprene seasonally and in response to short-term temperature extremes, and that species-specific differences in photosynthesis and isoprene emission may play an important role

  14. Biochemical, physiological and climatic influence on the emission of isoprenoides from Grey Poplar (Populus x canescens (Aiton) Sm.) and Holm Oak (Quercus ilex L.); Biochemische, physiologische und klimatische Einfluesse auf die Isoprenoidemission der Graupappel (Populus x canescens (Aiton) Sm.) und der Steineiche (Quercus ilex L.)

    Energy Technology Data Exchange (ETDEWEB)

    Mayrhofer, S.

    2007-05-15

    Because of their important role for the atmospheric chemistry, global daily and seasonal emission rates of isoprene and monoterpenes have to be estimated with accuracy. Therefore, detailed knowledge of biochemical and physiological processes within the plant metabolism has to be gathered. Afterwards the gained cognitions are used as information for process-based model calculations. The major scope of the work was therefore to enlarge basic knowledge of the regulation of isoprenoid emission, which is known to be dependent on several environmental factors, especially light and temperature. Measurements of diurnal isoprene emission have been performed in parallel on physiological, translational and transcriptional level on leaves of Grey Poplar (Populus x canescens), a strong isoprene emitting species. Additionally, examinations of diurnal monoterpene emission in connection to physiologic and enzymatic processes was conducted in leaves of Holm Oak (Quercus ilex), which emits a large spectrum of monoterpenes. Furthermore a hypothesis was tested, whether isoprene emission may serve the plant as antioxidative protection mechanism in order to overcome oxidative stress. In main parts, the following results have been reached: 1. In the first part of this work, isolation of PcDXR (DXR of Grey Poplar) from a cDNA-Genbank and heterologous expression of the isolated gene was accomplished. 2. Daytime variation of physiological and biochemical parameters of the isoprene emission of Grey Poplar was measured twice on 2 following days in 2 years. All together, measurements have been performed on 8 representative plants. 3. Quantitative RT-PCR elucidated the gene expression pattern of PcDXR and PcISPS in parallel to diurnal gas exchange measurements. Gene expression of PcISPS showed distinct diurnal courses with maximum values on the late morning, whereas PcDXR transcript levels stayed consistent over the day. No short-term influence of PPFD and leaf temperature has been observed on

  15. Natural production of Tuber aestivum in central Spain: Pinus spp. versus Quercus spp. brûlés

    Directory of Open Access Journals (Sweden)

    Luis G. Garcia-Montero

    2014-08-01

    Full Text Available Aim of study: Tuber aestivum is the most widespread edible truffle, with increasing commercial interest. This species can produce carpophores with conifer hosts, in contrast with the inability of Pinus spp. to induce fruiting in other truffle species such as Tuber melanosporum. Therefore the objective is to compare the characteristics and carpophore production of T. aestivum brûlés associated with Pinus spp. versus Quercus spp.Area of study: We studied the natural habitats of T. aestivum in the Alto Tajo Nature Reserve in central Spain.Material and methods: During 5 years, we monitored the production of carpophores and brûlé size of 145 T. aestivum brûlés associated with Pinus nigra subsp. salzmanni and P. sylvestris and Quercus ilex subsp. ballota and Q. faginea hosts. Statistical treatment was performed using the Statistica Program v. 6.Main Results: The size of brûlés associated with Pinus was significantly smaller than that of brûlés associated with Quercus. However, carpophore production per brûlé, and especially for brûlés of similar size, was greater when the host plant was a pine. After accounting for brûlé size, the production of brûlés associated with Pinus spp. was 2.23 (95% CI, between 1.35 and 3.69 and 1.61 (95% CI, between 1.02 and 2.54 times greater than the production of brûlés associated with Quercus faginea and Q. ilex subsp. ballota, respectively.Research highlights: The considerable ability of Pinus nigra subsp. salzmanni and P. sylvestris to form effective brûlés and to produce carpophores of Tuber aestivum in natural conditions was clearly demonstrated, and suggest that those species can be of use in the culture of T. aestivum.Key words: Summer truffle; Tuber aestivum; truffle culture; truffle ecology; Pinus spp.; Quercus spp.

  16. In vitro antibacterial activity of Quercus infectoria gall extracts against multidrug resistant bacteria.

    Science.gov (United States)

    Wan Nor Amilah, W A W; Masrah, M; Hasmah, A; Noor Izani, N J

    2014-12-01

    Antimicrobial activities of plants have long been evaluated for their promising use as antimicrobial agent and in minimizing the unwanted resistance effects of microorganisms. The study was conducted to evaluate the antibacterial activity of Quercus infectoria gall crude extracts against multidrug resistant (MDR) bacteria in vitro. The screening test was determined by disc diffusion technique using sterile filter paper discs impregnated with 1 mg/ disc (50 mg/ml) aqueous and ethanol extracts of Q. infectoria galls tested on five selected MDR bacterial strains. The minimum inhibitory concentration (MIC) was determined using the twofold serial micro dilution technique at concentration ranging from 5.00 mg/ml to 0.01 mg/ml. The minimum bactericidal concentration (MBC) was determined by sub culturing the microtitre wells showing no turbidity on the agar plate to obtain the MBC value. Both extracts showed substantial inhibitory effects against methicillin resistant coagulase negative Staphylococcus (MRCoNS) and methicillin resistant Staphylococcus aureus (MRSA). A slightly reduced inhibitory zone diameter was observed with MDR Acinetobacter sp. while no inhibitory effect was displayed among the extended spectrum beta lactamases (ESBL) K. pneumoniae and ESBL E. coli isolates. A significant difference in the zone sizes between both extracts was only observed in MRSA (p antibacterial activities and may be considered as a potentially good source of antimicrobial agent especially against MDR Gram positive bacteria.

  17. Scaling-up method for stand water consumption of Quercus variabilis water conservation forest

    Institute of Scientific and Technical Information of China (English)

    WANG Huatian; XING Lifeng; MA Lüyi; SUN Pengsen

    2006-01-01

    Single tree's sapwood scattering style and diurnal water consumption rhythm for different diameter classes were studied in a 48-year-old Quercus variabilis stand,water protection forest in Beijing.Results showed that the tree's sapwood area was closely related to diameter at breast height (DBH).Single tree's daily water consumption ascended as DBH and sapwood area increased.Daily water consumption of different diameter classes in September ascended steeply in the early morning and reached the peak around 11:00,and then descended slowly to the valley at 18:00.The course of daily accumulated water consumption was in accordance with a typical Richards model (R=0.985,8).Parameters of diameter-time equation for scal ing-up can be achieved by parameter-recovering method in the gradient of all diameter classes and at any time of a day,characteristic parameters of the course of daily stand water consumption were calculated from a modulated Richards equation derivative:Wdltl = (-7.147 + 1.174dl )[1- (-3,025.937 +di2.175)1/e(-0.01 1tj) ]1-di0.242

  18. FENOLOGÍA DEL ROBLE (Quercus humboldtii Bonpland EN POPAYÁN (CAUCA, COLOMBIA

    Directory of Open Access Journals (Sweden)

    CRISTIAN ANDRÉS PÉREZ L.

    Full Text Available Se realizó un registro fenológico del roble Quercus humboldtii Bonpland entre marzo del 2010 y marzo de 2011 - en el municipio de Popayán (Cauca, Colombia. La producción de flores femeninas y frutos jóvenes se presentó entre finales de marzo y principios de abril, correlacionándose positivamente estas dos fenofases durante todo el año con la temperatura (r=0,64 y r=0,44, respectivamente y en los inicios de estas dos fenofases se correlacionó con la precipitación (r=0,69 y r=0,92 respectivamente. Los frutos maduros aparecieron en mayo, aunque su cantidad se redujo hacia el final del año 2010 por el aborto de frutos en los meses anteriores. La actividad vegetativa se caracterizó por la presencia permanente de hojas nuevas, maduras, amarillas, sobremaduras y caída de follaje. Sin embargo, en agosto, debido al aumento significativo de la temperatura y a la disminución en la precipitación, se observó en los árboles caída de follaje, disminución de hojas maduras y producción de hojas nuevas.

  19. The effect of Quercus brantii gall extract on burn wound healing in rat

    Science.gov (United States)

    Haghdoost, Faraidoon; Baradaran Mahdavi, Mohammad Mehdi; Zolfaghari, Behzad; Sanei, Mohammad Hossein; Najafi, Somaye; Zandifar, Alireza; Manouchehri, Navid; Javanmard, Shaghayegh Haghjooy

    2016-01-01

    Objective(s): The aim of the present study was to evaluate the effect of Quercus brantii galls extract on the rat skin burn wound healing. Materials and Methods: Ethanol extract of the galls of Q. brantii was used to treat the induced burn wounds on the back of 32 Wistar rats divided into 4 groups. The groups were treated by placebo, 1%, 2% and 4% concentration gall extract gels for 14 days and the efficacy of treatment was assessed based on reduction of burn wound area, as well as histological and molecular characteristics. Results: The mean wound surface in the 14th day, in all groups treated by Q. brantii gall extracts were larger than control group and the differences were statistically significant (P=0.043). The mean histological wound healing scores were not statistically different. Analysis of nitric oxide and platelet derived growth factor concentration in wound fluids in the 5th day of study showed that there was not any significant difference between groups (P=0.468 and 0.312 respectively). Fibroblast growth factor (bFGF) concentration in the wound fluids, was significantly higher in group treated with 1% gall extract gel in comparison to the control group (P=0.026). Conclusion: Our results could not prove the significant positive effect of Q. brantii galls extract on the burning wound healing. More studies with more groups treated with different doses of the Q. brantii extract are recommended. PMID:27872712

  20. [Predicting the impact of global warming on the geographical distribution pattern of Quercus variabilis in China].

    Science.gov (United States)

    Li, Yao; Zhang, Xing-wang; Fang, Yan-ming

    2014-12-01

    The geographical distribution of Quercus variabilis in China with its climate characteristics was analyzed based on DIVA-GIS which was also used to estimate the response of future potential distribution to global warming by Bioclim and Domain models. Analysis results showed the geographical distribution of Q. variabilis could be divided into 7 subregions: Henduan Mountains, Yunnan-Guizhou Plateau, North China, East China, Liaodong-Shandong Peninsula, Taiwan Island, and Qinling-Daba Mountains. These subregions are across 7 temperature zones, 2 moisture regions and 17 climatic subregions, including 8 climate types. The modern abundance center of Q. variabilis is Qinling, Daba and Funiu mountains. The condition of mean annual temperature 7.5-19.8 degrees C annual precipitation 471-1511 mm, is suitable for Q. variabilis. Areas under the receiver operating characteristic curve (AUC values), of Domain and Boiclim models were 0.910, 0.779; the former predicted that the potential regions of high suitability for Q. variabilis are Qinling, Daba, Funiu, Tongbai, and Dabie mountains, eastern and western Yunnan-Guizhou Plateau, hills of southern Jiangsu and Anhui, part of the mountains in North China. Global warming might lead to the shrinking in suitable region and retreating from the south for Q. variabilis.

  1. COENOTICAL CHAINS OF ACER PLATANOIDES AND QUERCUS ROBUR IN THE FORESTS OF NOVGOROD-SEVERSKOYE POLESYE

    Directory of Open Access Journals (Sweden)

    Skliar V. G.

    2012-12-01

    Full Text Available We summarized information on association of small undergrowth of Norway maple (Acer platanoides L. and English oak (Quercus robur L. under the canopy of the forest with plants that form the grass-shrub layer within Novgorod-Severskoye Polesye. We founded that the association at certain extent depends on the type of population behavior of undergrowth and grasses. Small undergrowth of A. platanoides being the tolerant species according to the type of population behavior demonstrates negative association with the herbs that have high competitive ability. The pattern of association of A. platanoides with tolerant species depends on their vegetative mobility: the maple has positive association with species with no vegetative mobility and positive and negative association with species characterized by high extent of vegetative mobility. The undergrowth of Q. robur which is the competitive species due to population behavior shows positive association with the herbs that have high competitive ability. We estimated the coenotic parameters that are required for successful resumption of maple and oak in the region of research. We also shown that coenotic optimum for A. platanoides corresponds to the environment with weak intensity of competition in the living soil cover with thin grass layer and density of coverage does not exceed 50%. Q. robur has coenotic optimum among habitats in the herbaceous layer with domination of green moss and (or Convallaria majalis L., Fragaria vesca L. with no grains and density of coverage in living ground cover not more than 60%.

  2. Drought changes the dynamics of trace element accumulation in a Mediterranean Quercus ilex forest

    Energy Technology Data Exchange (ETDEWEB)

    Sardans, J. [Unitat d' Ecofisiologia CSIC-CEAB-CREAF, CREAF - Centre de Recerca Ecologica d' Aplicacions Forestals, Edifici C, Universitat Autonoma Barcelona, 08193 Bellaterra, Barcelona (Spain)]. E-mail: j.sardans@creaf.uab.cat; Penuelas, J. [Unitat d' Ecofisiologia CSIC-CEAB-CREAF, CREAF, Centre de Recerca Ecologica d' Aplicacions Forestals, Edifici C, Universitat Autonoma Barcelona, 08193 Bellaterra, Barcelona (Spain)

    2007-06-15

    We conducted a field drought manipulation experiment in an evergreen oak Mediterranean forest from 1999 to 2005 to investigate the effects of the increased drought predicted for the next decades on the accumulation of trace elements that can be toxic for animals, in stand biomass, litter and soil. Drought increased concentrations of As, Cd, Ni, Pb and Cr in roots of the dominant tree species, Quercus ilex, and leaf Cd concentrations in Arbutus unedo and of Phillyrea latifolia codominant shrubs. The increased concentration of As and Cd can aggravate the toxic capacity of those two elements, which are already next or within the levels that have been shown to be toxic for herbivores. The study also showed a great reduction in Pb biomass content (100-135 g ha{sup -1}) during the studied period (1999-2005) showing the effectiveness of the law that prohibited leaded fuel after 2001. The results also indicate that drought increases the exportation of some trace elements to continental waters. - Drought increased biomass concentrations of As and Cd and favors exportation of some trace elements to continental waters in a Mediterranean forest.

  3. Screening of Quercus infectoria gall extracts as anti-bacterial agents against dental pathogens.

    Science.gov (United States)

    Vermani, Archa

    2009-01-01

    A number of bacteria have now become antibiotic-resistant. This increases the importance of ayurvedic drugs. We report, here, the activity of different extracts (petroleum ether, chloroform, methanol and water) of Quercus infectoria galls against dental pathogens -- Streptococcus mutans, Streptococcus salivarius, Staphylococcus aureus, Lactobacillus acidophilus (designated) and Streptococcus sanguis (isolated). The cup-plate method was used in anti-bacterial activity of the extracts at concentration of 200 mg/ml against dental pathogens. Minimum inhibitory concentration (MIC) values of most effective extracts against the most susceptible bacteria were determined using a two-fold serial micro dilution method. Methanolic extract showed maximum anti-bacterial activity against all the bacteria. The most susceptible bacteria were S. sanguis followed by S. aureus, S. mutans, S. salivarius and L. acidophilus. The MIC values showed that methanolic extract was more effective than water extract. The plant has the potential to generate herbal metabolites. The crude extracts demonstrating anti-dental caries activity could result in the discovery of new chemical classes of antibiotics. These chemical classes of antibiotics could serve as selective agents for the maintenance of human health and provide bio-chemical tools for the study of infectious diseases.

  4. A phytosociological analysis of the Quercus coccifera L. stands in south Albania (NE Mediterranean

    Directory of Open Access Journals (Sweden)

    Jasprica Nenad

    2016-06-01

    Full Text Available The results of a phytosociological investigation of the Quercus coccifera L. stands occurring along the Adriatic and Ionian coasts in south Albania are given. The surveyed stands are localized in the Thermo-Mediterranean and Meso-Mediterranean belts. On the basis of literature and unpublished data, Q. coccifera stands extend from the shoreline up to 680 m of altitude, within the Quercetea ilicis vegetation zone. According to numerical analysis, Q. coccifera stands in south Albania can be divided into two broad groups forming macchia of 3–4 m height and low shrublands [0.5–1.5(-2 m] defined primarily by degree of human pressure and altitudes. In addition, relevés from Q. coccifera stands in Albania were differentiated from Croatian and Montenegrin the Fraxino orni-Quercetum cocciferae associations. Conversely, Q. coccifera stands in south Albania share several biological and ecological similarities with those of the eastern Adriatic coast: hemicryptophytes prevailed and the chorological spectrum highlights a clear dominance of the steno-Mediterraneans. With respect to indicator values, an important differentiation from the eastern Adriatic associations was shown only in higher light intensity of the stands in Albania.

  5. Evaluation of Hypoglycemic and Genotoxic Effect of Polyphenolic Bark Extract from Quercus sideroxyla

    Directory of Open Access Journals (Sweden)

    Marcela Soto-García

    2016-01-01

    Full Text Available Quercus sideroxyla is a wood species whose bark has phenolic compound and should be considered to be bioactive; the hypoglycemic and genotoxic properties of Q. sideroxyla bark were evaluated in this study. Total phenolic compound was determined in crude extract (CE and organic extract (OE. The OE has the highest amount of phenols (724.1±12.0 GAE/g. Besides, both CE and OE demonstrated effect over the inhibition of α-amylase in vitro. Hypoglycemic activity was assessed by glucose tolerance curve and the area under curve (UAC; OE showed the highest hypoglycemic activity. In addition, diabetes was induced by streptozotocin (65 mg/kg and the extracts (50 mg/kg were administered for 10 days; OE showed hypoglycemic effect compared with diabetic control and decreased hepatic lipid peroxidation. Acute toxicity and genotoxicity were evaluated in CE; results of acute toxicity did not show any mortality. Besides, the comet assay showed that CE at a dose of 100 mg/kg did not show any genotoxic effect when evaluated at 24 h, whereas it induced slight damage at 200 mg/kg, with the formation of type 1 comets.

  6. [Effects of coat and sowing depth on seed germination and early seedling growth of Quercus wutaishanica].

    Science.gov (United States)

    Yan, Xing-Fui; Qiu, Zhi-Hu; Zhang, Qiang; Zhang, Kao-Wen; Zhou, Yun-Feng

    2014-01-01

    Under shade environment in glasshouse, the effects of seed coat and sowing depth (0, 2, 5, 10 or 15 cm) on seed germination and early seedling growth of Quercus wutaishanica were studied. Seed coat had obvious inhibiting effects on the germination of Q. wutaishanica seeds. The germination percentage of uncoated seeds increased significantly, averagely by 19.4% at different sowing depths. The germination index and vigor index were increased significantly and the germination was speeded in the peeling treatment. The germination percentages of uncoated and coated seeds were the highest at the sowing depth of 2 cm with 78.9% and 62.2%, respectively. The germination index and vigor index were the highest at the sowing depth of 2 cm, while the coefficient of rate of germination were the highest at the sowing depth of 5 cm. Leaf area per seedling and dry mass of seedlings increased significantly in the peeling treatment compared with those in the unpeeling treatment, but specific root length decreased significantly. The shoot height in the peeling and unpeeling treatments were the highest at the sowing depth of 5 cm with 13.8 and 14.2 cm, respectively. With the increasing of sowing depth, the basal stem diameter of seedlings increased, but tap-root length, number of lateral root and maximum of lateral root all decreased. Sowing depth had little influence on dry mass of seedlings.

  7. Nutrient composition and starch characteristics of Quercus glandulifera Bl. seeds from China.

    Science.gov (United States)

    Li, Songnan; Zhou, Yibin; Liu, Mei; Zhang, Yang; Cao, Shengnan

    2015-10-15

    The chemical composition and starch characteristics of acorn (Quercus glandulifera Bl.) were studied. The moisture content of acorn seeds was 7.55%. The crude fat, crude protein, dietary fiber, total ash, and nitrogen-free extract contents of acorn seed were 4.20%, 10.16%, 2.95%, 0.03%, and 82.66%, respectively, on a dry weight basis. Linoleic, oleic, and palmitic were the most predominant fatty acids. UFA:SFA and SFA:MUFA:PUFA ratios were 2.6:1 and 1.25:1.34:1, respectively. The essential amino acid content from acorn seeds was low based on FAO reference values. Acorn seeds were a good source of Fe, Zn, and Mn. The contents of vitamins A and E were 1.40 mg RE/100g and 10.78 mg/100 g, respectively. Starch extracted from acorn seeds had round, triangle, and elliptical morphology with granule size of 3.3-126.2 μm. The ratio between amylose and amylopectin contents was 25.39:72.94. Acorn starch had a typical A-type crystal pattern with 23.53% relative crystallinity. The gelatinization temperature was 66.53 °C and the transition enthalpy was 4.33 J/g.

  8. Conservation Strategies for the Threatened Quercus Semecarpifolia Sm. A Himalayan Timberline Oak

    Directory of Open Access Journals (Sweden)

    Hemlata BISHT

    2011-12-01

    Full Text Available Quercus semecarpifolia Sm. is a temperate, timberline, multipurpose oak species. It plays an important role in the Himalayan ecosystem. Human pressure, predation, short-lived acorns, failure of good seed crop every year, poor regeneration, desiccation, frost sensitivity and climate change may lead to complete extinction of the species in a near future. Immediate attention to conservation and restoration measures of the Himalayan ecosystem, in which this species grows, is required. Thus, an experiment was designed to analyze the role of planting stock and micro-sites for the regeneration of Q. semecarpifolia in-situ. For that purpose, 16 microsites with presence/absence of litter, canopy and sunlight were identified, where seeds/propagules were planted. The presence of litter, canopy and sunlight influenced the seedling production, mainly impairing the processes, leading to the expansion in diameter of the radicle, causing shoot/root emergence. Radicle emergence took place in all the seeds immediately after shedding but only 20% of seedlings recovered; however, when the stored seeds were sown as soon as the emerging radicle attained 10-15cm in length and 2-3cm in diameter, 80% of seedlings were recovered. Surprisingly, after being detached from the seed the swollen radicle acted as a propagule and produced 80% seedlings irrespective of the microsites; however, radicles detached prior to diameter expansion failed to produce seedlings which is a crucial insight for promoting seedling production.

  9. Oak (Quercus Floribunda: A Prominent Indigenous Multipurpose Tree for Carbon Storage and Sequestration Potential

    Directory of Open Access Journals (Sweden)

    K. K. Pandey

    2015-12-01

    Full Text Available A dynamic growth model (CO2FIX has been used for estimating the carbon sequestration potential of Oak (Quercus floribunda, an indigenous multipurpose tree used for timber, fuel wood, fiber and specially fodder in addition to its ability of soil binder. The present study has been carried out in the campus of V.C.S.G. College of Horticulture, U.U.H.F., Bharsar, Pauri Garhwal, Uttarakhand. It is capable of thriving on snow and heavy rainfall condition. CO2FIX was parameterized for a simulation of 100 years respectively. The results indicate that the long term tree biomass accumulated was 120.11 t/ha in above ground and 79.89 t/ha in below ground (Soil Carbon component respectively at the end of simulation period assuming a tree density of 825t/ha (approximately. The net annual carbon sequestration for Oak over the entire simulation period was 1.9 Mg C ha-1 yr -1 (t/ha/yr. Useful for scientific planning and effective implementation of Forestry and Agroforestry developmental programmes at district level as well as at State level for the development of country. For future research work following are few suggestions for better planning and development of State. This type of study can be taken including other parameters/resources such as different trees, different area, and different state and different country as well.

  10. Pedunculate oak forests (Quercus robur L. survey in the Ticino Regional Park (Italy by remote sensing

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    Rossini M

    2007-01-01

    Full Text Available Pedunculate oak forests (Quercus robur L. in the Ticino Regional Park (Italy show sensible damage conditions due to different environmental stresses: insect attacks, summer drought and air pollution. Knowing whether oaks are healthy or stressed can provide useful information in order to conserve the forest ecosystems and avoid the lost of valuable natural resources. Environmental stresses can affect tree biochemical and structural variables, such as the concentration, composition and efficiency in light harvesting of foliar pigments, and the Leaf Area Index (LAI. Interest in the use of these variables for forest condition assessment has recently increased because they can be indirectly estimated from remote observations at leaf and canopy level. In particular, in this research we found that total chlorophyll (Chl concentration, a biochemical variable related to crown discoloration rate, was the most suitable variable for the detection of pedunculate oak decline in the Ticino Park. A regression analysis between Chl concentration and optical indices computed from hyperspectral MIVIS data was performed in order to estimate Chl concentration from remote observations. The good correlation between field measurements of Chl concentration and MIVIS optical indices allowed the development of a model to map Chl concentration across the Ticino Park forested area. Promising results demonstrated that remotely sensed data can provide an accurate estimation of Chl concentration and indicated the potential of this technique for forest condition monitoring.

  11. Behavior of pubescent oak (Quercus pubescens Willd. wood to different thermal treatments

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    Todaro L

    2015-12-01

    Full Text Available Quercus pubescens Willd. is a common oak species in the Mediterranean area, where it is currently exploited mainly for purposes such as firewood. To improve the technological properties of its wood, various steaming and/or heat treatments were applied to 160 wood samples from a southern Italian stand, cut from either sapwood or heartwood, while 20 samples served as controls. Steaming was carried out in an autoclave at 120 °C, whereas heat treatments were performed in an oven at 150 or 200 °C for 3 or 6 h. The equilibrium moisture content, swelling, mass loss, wood density, compression strength, color variation, and lignin content of the samples were measured and compared among treatments. The swelling and water adsorption of wood samples decreased due to the hydrothermal treatments. The mass loss was strictly related to the temperature and duration of the heat treatments, whereas it was not influenced by the steaming treatment. The average axial compression strength value was positively influenced by the combination of steaming and heat treatments. A significant and general darkening of color was also observed for the harshest treatments, while an increase of lignin content was detected mainly in the sapwood. Thus, pubescent oak wood subjected to steaming and heat treatments may acquire useful characteristics suitable for its industrial use.

  12. Detection of hybrids in nature: application to oaks (Quercus suber and Q. ilex).

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    Burgarella, C; Lorenzo, Z; Jabbour-Zahab, R; Lumaret, R; Guichoux, E; Petit, R J; Soto, A; Gil, L

    2009-05-01

    Powerful and accurate detection of first-generation (F1) hybrids and backcrosses in nature is needed to achieve a better understanding of the function and dynamics of introgression. To document the frequency of ongoing interspecific gene exchange between two Mediterranean evergreen oaks, the cork oak (Quercus suber) and the holm oak (Q. ilex), we analyzed 1487 individuals originating from across the range of the two species using eight microsatellite loci and two Bayesian clustering approaches (implemented in the programs STRUCTURE and NEWHYBRIDS). Simulated data were used to assess the differences between the two clustering methods and to back up the choice of the threshold value for the posterior probability to discriminate admixed from pure individuals. We found that the use of STRUCTURE resulted in the highest power to detect hybrids, whereas NEWHYBRIDS provided the highest accuracy. Irrespective of the approach, the two species were clearly distinguished as independent genetic entities without any prior information. In contrast with previous reports, we found no evidence for unidirectional introgression. The overall hybridization rate was very low (<2% of introgressed individuals). Only two individuals were identified as F1 hybrids and five as early backcrosses. This work shows that the combined application of the two complementary Bayesian approaches and their systematic validation with simulations, fit for the case at hand, helps gain resolution in the identification of admixed individuals.

  13. Quercus Suber L. Cork Extracts Induce Apoptosis in Human Myeloid Leukaemia HL-60 Cells.

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    Bejarano, Ignacio; Godoy-Cancho, Belén; Franco, Lourdes; Martínez-Cañas, Manuel A; Tormo, María A

    2015-08-01

    Quercus suber L. cork contains a diversity of phenolic compounds, mostly low molecular weight phenols. A rising number of reports support with convergent findings that polyphenols evoke pro-apoptotic events in cancerous cells. However, the literature related to the anti-cancer bioactivity of Q. suber L. cork extractives (QSE) is still limited. Herein, we aim to describe the antitumor potential displayed by cork extractives obtained by different extraction methods in the human promyelocytic leukaemia cells. In order to quantify the effects of QSE on cancer cells viability, phosphatidylserine exposure, caspase-3 activity, mitochondrial membrane potential and cell cycle were evaluated. The results indicated that the QSE present a time-dependent and dose-dependent cytotoxicity in the human promyelocytic leukaemia cells. Such a noxious effect leads these leukaemia cells to their death through apoptotic processes by altering the mitochondrial outer membrane potential, activating caspase-3 and externalizing phosphatidylserine. However, cells cycle progression was not affected by the treatments. This study contributes to open a new way to use this natural resource by exploiting its anti-cancer properties. Moreover, it opens new possibilities of application of cork by-products, being more efficient in the sector of cork-based agriculture. Copyright © 2015 John Wiley & Sons, Ltd.

  14. Recurrent fires and environment shape the vegetation in Quercus suber L. woodlands and maquis.

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    Schaffhauser, Alice; Curt, Thomas; Véla, Errol; Tatoni, Thierry

    2012-06-01

    The effects of fire recurrence on vegetation patterns in Quercus suber L. and Erica-Cistus communities in Mediterranean fire-prone ecosystems of south-eastern France were examined on stands belonging to 5 fire classes, corresponding to different numbers of fires (from 0 to 4) and time intervals between fires since 1959. A common pool of species was identified among the plots, which was typical of both open and closed maquis. Fire recurrence reduced the abundance of trees and herbs, whereas it increased the abundance of small shrubs. Richness differed significantly between the most contrasting classes of fire recurrence, with maximal values found in control plots and minimal values in plots that had burned recurrently and recently. Equitability indices did not vary significantly, in contrast to Shannon's diversity index which mostly correlated with richness. Forest ecosystems that have burnt once or twice in the last 50 years were resilient; that is to say they recovered a biomass and composition similar to that of the pre-fire state. However, after more than 3-4 fires, shrubland communities displayed lower species richness and diversity indices than unburned plots. The time since the last fire and the number of fires were the most explanatory fire variables, governing the structure of post-fire plant communities. However, environmental factors, such as slope or exposure, also made a significant contribution. Higher rates of fire recurrence can affect the persistence or expansion of shrublands in the future, as observed in other Mediterranean areas.

  15. Proteins associated with cork formation in Quercus suber L. stem tissues.

    Science.gov (United States)

    Ricardo, Cândido P P; Martins, Isabel; Francisco, Rita; Sergeant, Kjell; Pinheiro, Carla; Campos, Alexandre; Renaut, Jenny; Fevereiro, Pedro

    2011-08-12

    Cork (phellem) formation in Quercus suber stem was studied by proteomic analysis of young shoots of increasing age (Y0, Y1 and Y4) and recently-formed phellem (Y8Ph) and xylem (Y8X) from an 8-year-old branch. In this study 99 proteins were identified, 45 excised from Y8X and 54 from Y8Ph. These ones, specifically associated with phellem, are of "carbohydrate metabolism" (28%), "defence" (22%), "protein folding, stability and degradation" (19%), "regulation/signalling" (11%), "secondary metabolism" (9%), "energy metabolism" (6%), and "membrane transport" (2%). The identification in phellem of galactosidases, xylosidases, apiose/xylose synthase, laccases and diphenol oxidases suggests intense cell wall reorganization, possibly with participation of hemicellulose/pectin biosynthesis and phenol oxidation. The identification of proteasome subunits, heat shock proteins, cyclophylin, subtilisin-like proteases, 14-3-3 proteins, Rab2 protein and enzymes interacting with nucleosides/nucleic acids gives additional evidence for cellular reorganization, involving cellular secretion, protein turnover regulation and active control processes. The high involvement in phellem of defence proteins (thioredoxin-dependent peroxidase, glutathione-S-transferase, SGT1 protein, cystatin, and chitinases) suggests a strong need for cell protection from the intense stressful events occurring in active phellem, namely, desiccation, pests/disease protection, detoxification and cell death. Identically, highly enhanced defence functions were previously reported for potato periderm formation.

  16. Studies on the ectomycorrhizal community in a declining Quercus suber L. stand.

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    Lancellotti, Enrico; Franceschini, Antonio

    2013-10-01

    This survey was carried out in a Quercus suber L. stand with many trees affected by the disease "oak decline". Its aim was to obtain information about both the belowground ectomycorrhizal fungal community in a declining Q. suber stand as a whole, and the ectomycorrhizal fungal community of individual tree (EFT) detected in healthy and diseased plants. To this end, we first categorized the trees into four different decline classes (one for healthy plants and three for diseased plants) and then, by using morphological and molecular tools, we identified the ectomycorrhizas isolated from samples collected near the trees with different declining classes. The ectomycorrhizal community as a whole was seen to be composed of numerous ectomycorrhizal fungal species, only some of which appeared to be dominant (Cenococcum geophilum, Lactarius chrysorrheus, and some species of Tomentella genus), while most occurred sporadically. Results show that all root tips observed are mycorrhized and that decline class does not influence the number of ectomycorrhizal root tips found in the EFTs, thus oak decline does not impact the investment in ectomycorrhizal symbiosis. However, some statistical differences can be observed in the values of evenness and taxonomic distinctness in the EFT associated with trees with different states of health. Finally, both the analysis of similarity test and the ordination technique highlight a compositional difference between the EFT associated with trees in different health conditions, but also suggest that other factors may play a role in causing these differences.

  17. Demonstration of pectic polysaccharides in cork cell wall from Quercus suber L.

    Science.gov (United States)

    Rocha, S M; Coimbra, M A; Delgadillo, I

    2000-06-01

    Scanning electron microscopy (SEM) and chemical analysis were used to observe the cell wall changes that occur in cork with "mancha amarela", when compared to a standard cork. To mimic the microbial attack exhibited in cork with mancha amarela, the standard cork was treated enzymatically with commercial pectinase and hemicellulase preparations. The tissues treated with pectinase were comparable with those attacked with mancha amarela. Both were composed by deformed and wrinkly cells and exhibited cell wall separation at the middle lamella level, which suggests solubilization/removal of the pectic polysaccharides. The cork cell wall material, prepared as alcohol-insoluble residue, was fractionated by hot water (Pect(H)()2(O)) and hot dilute acid (Pect(acid)). The relatively large amount of hexuronic acid and the occurrence of Ara in the SPect(H)()2(O) and SPect(acid) allow to confirm, as far as we know, for the first time the presence of pectic polysaccharides in the cell walls of cork from Quercus suber L. They accounted for ca. 1.5% of the cork and may consist of polymers with long side chains of arabinosyl residues. These polymers have to be taken into account in any realistic model of the cork cell wall. Cork with mancha amarela contained a smaller amount of pectic polysaccharides (ca. 0.5%), which confirms that the cellular separation observed by SEM is related to the degradation/removal of the middle lamella pectic polysaccharides.

  18. Composition of suberin extracted upon gradual alkaline methanolysis of Quercus suber L. cork.

    Science.gov (United States)

    Lopes, M H; Gil, A M; Silvestre, A J; Neto, C P

    2000-02-01

    The monomeric composition of suberin extracts obtained by gradual alkaline methanolysis of Quercus suber cork was determined by gas chromatography-mass spectrometry (GC-MS). Results show that 1-alkanols and alkanoic and alpha,omega-alkanedioic acids are preferentially removed upon mild alkaline conditions, whereas mid-chain-modified omega-hydroxyalkanoic acids are preferentially removed under stronger alkaline conditions. Saturated omega-hydroxyalkanoic acids are found to be abundant in all suberin extracts. These results are consistent with two distinct suberin fractions with different locations in cork cell walls and/or esterification degrees. It is proposed that these fractions correlate with the two main suberin peaks in the solid state (13)C NMR spectra of cork and suberin extracts. Quantitative GC-MS analysis showed that suberin monomers comprise approximately 30% (w/w) of the suberin extracts, the remaining comprising nonvolatile structures with high M(n) values, as measured by vapor pressure osmometry. The presence of a large fraction of high molecular weight aliphatic structures in suberin extracts is supported by the corresponding NMR spectra.

  19. Corky, a gypsy-like retrotransposon is differentially transcribed in Quercus suber tissues

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    Rocheta Margarida

    2012-08-01

    Full Text Available Abstract Background Transposable elements (TEs make up a large part of eukaryotic genomes. Due to their repetitive nature and to the fact that they harbour regulatory signals, TEs can be responsible for chromosomal rearrangements, movement of gene sequences and evolution of gene regulation and function. Retrotransposon ubiquity raises the question about their function in genomes and most are transcriptionally inactive due to rearrangements that compromise their activity. However, the activity of TEs is currently considered to have been one of the major processes in genome evolution. Findings We report on the characterization of a transcriptionally active gypsy-like retrotransposon (named Corky from Quercus suber, in a comparative and quantitative study of expression levels in different tissues and distinct developmental stages through RT-qPCR. We observed Corky’s differential transcription levels in all the tissues analysed. Conclusions These results document that Corky’s transcription levels are not constant. Nevertheless, they depend upon the developmental stage, the tissue analysed and the potential occurring events during an individuals’ life span. This modulation brought upon by different developmental and environmental influences suggests an involvement of Corky in stress response and during development.

  20. Antioxidant and biological properties of bioactive phenolic compounds from Quercus suber L.

    Science.gov (United States)

    Fernandes, Ana; Fernandes, Iva; Cruz, Luís; Mateus, Nuno; Cabral, Miguel; de Freitas, Victor

    2009-12-09

    Phenolic compounds, namely, hydrolyzable tannins and low molecular weight phenolic compounds, were isolated and purified from Portuguese cork from Quercus suber L. Some of these compounds were studied to evaluate their antioxidant activity, including free-radical scavenging capacity (DPPH method) and reducing capacity (FRAP method). All compounds tested showed significant antioxidant activity, namely, antiradical and reducing properties. The antiradical capacity seemed to increase with the presence of galloyl groups. Regarding the reducing capacity, this structure-activity relationship was not so clear. These compounds were also studied to evaluate the growth inhibitory effect on the estrogen responsive human breast cancer cell line (ER+) MCF-7 and two other colon cancer cell lines (Caco-2 and HT-29). Generally, all the compounds tested exhibited, after a continuous exposure during a 48 h period, a dose-dependent growth inhibitory effect. Relative inhibitory activity was primarily related to the number of phenolic hydroxyl groups (galloyl and HHDP moieties) found in the active structures, with more groups generally conferring increased effects, except for HHDP-di-galloyl-glucose. Mongolicain B showed a greater potential to inhibit the growth of the three cell lines tested, identical to the effect observed with castalagin. Since these compounds are structurally related with each other, this activity might be based within the C-glycosidic ellagitannin moiety.

  1. Cryopreservation of Quercus suber somatic embryos by encapsulation-dehydration and evaluation of genetic stability.

    Science.gov (United States)

    Fernandes, Pedro; Rodriguez, Eleazar; Pinto, Glória; Roldán-Ruiz, Isabel; De Loose, Marc; Santos, Conceição

    2008-12-01

    We describe an encapsulation and dehydration procedure for the cryopreservation of cork oak (Quercus suber L.) somatic embryos that resulted in at least 90% survival. Genetic stability of the regenerated material was assessed by flow cytometry (FCM), amplified fragment length polymorphisms (AFLP) and simple sequence repeats (SSR). Cryopreservation of embryogenic clusters involved encapsulation of each cluster in an alginate bead, followed by a 3-day culture in 0.7 M sucrose and subsequent desiccation to 25 or 35% water content (WC), followed by freezing in liquid nitrogen. Thawed, cryopreserved somatic embryos had high viability and exhibited long-term survival. No morphological differences were observed between somatic embryos desiccated to 25 and 35% WC. Analysis of DNA ploidy stability of control (i.e., encapsulated and dehydrated but not frozen) and cryopreserved material by flow cytometry showed no significant differences. Similarly, DNA-marker analyses (AFLPs and SSR) revealed no significant differences between control and cryopreserved samples at the DNA-sequence level. Nonetheless, because polymorphisms were found between control material and samples cryopreserved and desiccated to 25% WC, the 35% WC method is recommended for cryopreservation of this tissue type. Cryopreservation of Q. suber somatic embryos by this encapsulation-dehydration procedure has potential for use in long-term conservation programs.

  2. Histology of Organogenic and Embryogenic Responses in Cotyledons of Somatic Embryos of Quercus Suber L.

    Science.gov (United States)

    Puigderrajols; Celestino; Suils; Toribio; Molinas

    2000-05-01

    In cork oak (Quercus suber L.), recurrent embryogenesis is produced in vitro through autoembryony without exogenous plant growth regulators (PGRs); secondary embryos appear on the embryo axis but seldom on cotyledons. Focusing mainly on the histological origin of neoformations, we investigated the influence of the embryo axis and exogenous PGRs on the embryogenic potential of somatic embryo cotyledons. Isolated cotyledons of somatic embryos became necrotic when cultured on PGR-free medium but gave secondary embryos when cultured on media containing benzyladenine and naphthaleneacetic acid. Cotyledons of cork oak somatic embryos are competent to give embryogenic responses. Isolated cotyledons without a petiole showed a lower percentage of embryogenic response than did those with a petiole. In petioles, somatic embryos arose from inner parenchyma tissues following a multicellular budding pattern. Joined to the embryo axis, cotyledons did not show morphogenic responses when cultured on PGR-free medium but revealed budlike and phylloid formations when cultured on medium with PGRs. The different morphogenic behavior displayed by somatic cotyledons indicates an influence of the embryo axis and indicates a relationship between organogenic and embryogenic regeneration pathways.

  3. Cryopreservation of embryogenic cultures from mature Quercus suber trees using vitrification.

    Science.gov (United States)

    Valladares, Silvia; Toribio, Mariano; Celestino, Cristina; Vieitez, Ana M

    2004-01-01

    Recent progress in somatic embryogenesis from selected mature trees of Quercus suber, has led to a demand for maintenance of a large number of selected embryogenic lines. To facilitate the management of this material a protocol for the long-term storage of this germplasm should be defined. This study reports on the use of a simple vitrification procedure for the successful cryopreservation of three cork oak embryogenic lines. High embryo recovery levels (88-93 percent) were obtained by first preculturing 2-4 mg clumps of two or three globular embryos on semisolid medium containing 0.3 M sucrose for three days, followed by incubation in PVS2 vitrification solution at 0 degree C for 60 min before direct immersion in liquid nitrogen. The mean number of embryos produced per explant was significantly greater for cryostored embryos than for untreated stock cultures, but the productivity of the latter was recovered in subsequent subcultures of the material produced by cryostored embryos. The germination and plant regeneration rates achieved by cultures derived from cryostored embryos, around 60 percent, were similar to those of non-cryopreserved stock cultures.

  4. Enzymatic isolation and structural characterisation of polymeric suberin of cork from Quercus suber L.

    Science.gov (United States)

    Rocha, S M; Goodfellow, B J; Delgadillo, I; Neto, C P; Gil, A M

    2001-01-10

    An enzymatic method has been used to isolate, for the first time, polymeric suberin from the bark of Quercus suber L. or cork. This was achieved by solvent extraction (dichloromethane, ethanol and water), followed by a step-by-step enzymatic treatment with cellulase, hemicellulase and pectinase, and a final extraction with dioxane/water. The progress of suberin isolation was monitored by Fourier transform infrared spectroscopy using a photoacoustic cell (FTIR-PAS). The material obtained (polymeric suberin (PS)) was characterised by solid-state and liquid-state nuclear magnetic resonance, FTIR-PAS and vapour pressure osmometry, and compared with the suberin fraction obtained by alkaline depolymerisation (depolymerised suberin (DS)). The results showed that PS is an aliphatic polyester of saturated and unsaturated fatty acids, with an average molecular weight (M(w)) of 2050 g mol(-1). Although this fraction represents only 10% of the whole suberin of cork, its polymeric nature gives valuable information about the native form of the polymer. DS was found to have an average M(w) of 750 g mol(-1) and to comprise a significant amount of acidic and alcoholic short aliphatic chains.

  5. Differential DNA Methylation Patterns Are Related to Phellogen Origin and Quality of Quercus suber Cork

    Science.gov (United States)

    Costa, Augusta; Roussado, Cristóvão; Gonçalves, Elsa; Costa, Rita; Graça, José; Oliveira, M. Margarida

    2017-01-01

    DNA methylation is thought to influence Quercus suber cork quality, which is the main constraint for its economic valorisation. However, a deep knowledge of the cytosine methylation patterns disclosing the epigenetic variability of trees with different cork quality types is totally missing. This study investigates the hypothesis that variations in DNA methylation contribute to differences in cork cellular characteristics directly related to original or traumatic phellogen activity. We used MSAPs (Methylation Sensitive Amplified Polymorphism) to assess DNA methylation patterns of cork and leaf tissues of Q. suber adult trees growing in three cork oak stands. The relationship between the detected polymorphisms and the diversity of cork quality traits was explored by a marker-trait analysis focusing on the most relevant quality characteristics. Populations differed widely in cork quality, but only slightly in degree of epigenetic differentiation. Four MSAP markers (1.3% of the total) were significantly associated with the most noteworthy quality traits: wood inclusions (nails) and porosity. This evidence supports the potential role of cytosine methylation in the modulation of differential phellogen activity either involved in localized cell death or in pore production, resulting in different cork qualities. Although, the underlying basis of the methylation polymorphism of loci affecting cork quality traits remain unclear, the disclosure of markers statistically associated with cork quality strengthens the potential role of DNA methylation in the regulation of these traits, namely at the phellogen level. PMID:28045988

  6. Genetic Differentiation between Quercus frainetto Ten. and Q. pubescens Willd. in Romania

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    Alexandru Lucian CURTU

    2011-05-01

    Full Text Available Little is known about genetic differences among Quercus frainetto and Q. pubescens, two species of section Dascia Kotschy (subgenus Lepidobalanus, white oaks that reach in Romania the margins of their natural distribution range. A set of genomic SSRs (simple sequence repeats and EST (expressed sequence tags-SSRs was used to estimate the genetic differentiation among four natural populations of the two species. Q. pubescens had higher values of genetic diversity than Q. frainetto, although the differences were not significant. Two out of seven marker-loci, QrZAG112 and QpZAG110, displayed very high FST values. Averaged across loci, the genetic differentiation was high and significant (FST = 0.067. Genetic distances were much higher among species than among populations within species. A Bayesian analysis indicated that two is the most appropriate number of genetic clusters. Using a blind procedure (i.e. based on multilocus genotypes only the vast majority of sampled individuals (90% could be assigned to the cluster corresponding to their phenotypes. When information about sampling localities was introduced in the assignment test, all individual trees were correctly classified. The higher degree of admixture in Q. frainetto as compared to Q. pubescens may be explained by different rates of introgressive hybridization.

  7. Imprints of natural selection along environmental gradients in phenology-related genes of Quercus petraea.

    Science.gov (United States)

    Alberto, Florian J; Derory, Jérémy; Boury, Christophe; Frigerio, Jean-Marc; Zimmermann, Niklaus E; Kremer, Antoine

    2013-10-01

    We explored single nucleotide polymorphism (SNP) variation in candidate genes for bud burst from Quercus petraea populations sampled along gradients of latitude and altitude in Western Europe. SNP diversity was monitored for 106 candidate genes, in 758 individuals from 32 natural populations. We investigated whether SNP variation reflected the clinal pattern of bud burst observed in common garden experiments. We used different methods to detect imprints of natural selection (FST outlier, clinal variation at allelic frequencies, association tests) and compared the results obtained for the two gradients. FST outlier SNPs were found in 15 genes, 5 of which were common to both gradients. The type of selection differed between the two gradients (directional or balancing) for 3 of these 5. Clinal variations were observed for six SNPs, and one cline was conserved across both gradients. Association tests between the phenotypic or breeding values of trees and SNP genotypes identified 14 significant associations, involving 12 genes. The results of outlier detection on the basis of population differentiation or clinal variation were not very consistent with the results of association tests. The discrepancies between these approaches may reflect the different hierarchical levels of selection considered (inter- and intrapopulation selection). Finally, we obtained evidence for convergent selection (similar for gradients) and clinal variation for a few genes, suggesting that comparisons between parallel gradients could be used to screen for major candidate genes responding to natural selection in trees.

  8. Site quality assessment of degraded Quercus frainetto stands in central Greece

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    Kitikidou K

    2015-02-01

    Full Text Available The potential yield of a site is measured by site index, which is defined as the dominant height of a stand at a base age. A site index model for site quality assessment of Quercus frainetto (Hungarian oak stands in central Greece was developed using a base age of 50 years. Data were collected from 39 temporary sample plots of 10 x 10 m. Linear regression models widely used in site index studies were fitted to height-age data. The adjusted coefficient of determination (R2adj, root mean square error (RMSE, bias, coefficient of determination for the prediction (R2pr and residual plots were used for the choice of the best-fitting model. The best model was H = -0.231+0.251A-0.001A2, where H is the predicted height at age A. The guide curve method was adopted in constructing the sites curves, with the chosen model as the guide curve. Based on this curve, the study area was divided into three site quality classes (I to III, with class I representing the best and class III the poorest. Also, the presence of a Simpson’s paradox in these analyses is discussed. The results showed that a 50-year-old stand in the study area attained an average dominant height of about 11, 8 and 6 m on site quality classes I, II and III, respectively. The Hungarian oak stands of the present study can be considered very low productivity stands.

  9. Post-fire recolonization of dominant epiphytic lichen species on Quercus hypoleucoides (Fagaceae).

    Science.gov (United States)

    Romagni, J G; Gries, C

    2000-12-01

    Following a forest fire (27 500 ha) in 1994, post-fire recolonization of Quercus hypoeleucoides by epiphytic lichens was documented as changes in lichen cover, number of small thalli, specific factors that affected reestablishment of lichens, and modes of dispersal. Three sites in the Chiricahua Mountains (Arizona, USA) were chosen according to the severity of fire damage-unburned, moderately burned, and severely burned. From 1994 through 1997, the amount of dead lichen cover significantly increased at the moderately burned site. For the same time period, the amount of live lichen cover significantly increased at the severely burned site. Numbers of new thalli increased significantly at the severely burned site each year but only in the last year (1996-1997) for the moderately burned site. Bark texture and proximity to trees with lichens were among the most important physical factors for recolonization. The most important means of dispersal for Flavopunctelia praesignis was fragmentation. For Punctelia hypoleucites, the primary means of dispersal was spores. Increases in live lichen cover and numbers of new thalli occur faster in severely burned areas probably due to the loss of lichens on tree trunks, which provides space and a lack of competition.

  10. Epigenetic and hormonal profile during maturation of Quercus Suber L. somatic embryos.

    Science.gov (United States)

    Pérez, Marta; Viejo, Marcos; LaCuesta, Maite; Toorop, Peter; Cañal, María Jesús

    2015-01-15

    Somatic embryogenesis is a powerful alternative to conventional mass propagation of Quercus suber L. However, poor quality and incomplete maturation of somatic embryos restrict any application. Given that epigenetic and hormonal control govern many developmental stages, including maturation of zygotic embryos, global DNA methylation and abscisic acid (ABA) were analyzed during development and maturation of cork oak somatic embryos. Our results indicated that development of somatic embryos concurred with a decrease in 5-mdC. In contrast, endogenous ABA content showed a transient increase with a peak in immature E2 embryos denoting the onset of the maturation phase. A cold stratification phase was necessary for embryos to acquire germination ability, which coincided with a significant decrease in 5-mdC and ABA content. Immunohistochemical analyses showed that there was a specific spatial-temporal regulation during embryogenesis, particularly after the cold treatment. The acquisition of germination capacity concurred with a general low 5-mdC signal in the root meristem, while retention of the 5-mdC signal was mainly located in the shoot meristem and provascular tissues. Conversely, ABA immunolocalization was mainly located in the root and shoot apical meristems. Furthermore, a strong decrease in the ABA signal was observed in the root cap after the stratification treatment suggesting a role for the root cap during development of somatic embryos. These results suggest that, in addition to ABA, epigenetic control appears to play an important role for the correct maturation and subsequent germination of cork oak somatic embryos.

  11. The distribution of Quercus suber chloroplast haplotypes matches the palaeogeographical history of the western Mediterranean.

    Science.gov (United States)

    Magri, D; Fineschi, S; Bellarosa, R; Buonamici, A; Sebastiani, F; Schirone, B; Simeone, M C; Vendramin, G G

    2007-12-01

    Combining molecular analyses with geological and palaeontological data may reveal timing and modes for the divergence of lineages within species. The Mediterranean Basin is particularly appropriate for this kind of multidisciplinary studies, because of its complex geological history and biological diversity. Here, we investigated chloroplast DNA of Quercus suber populations in order to detect possible relationships between their geographical distribution and the palaeogeographical history of the western Mediterranean domain. We analysed 110 cork oak populations, covering the whole distribution range of the species, by 14 chloroplast microsatellite markers, among which eight displayed variation among populations. We identified five haplotypes whose distribution is clearly geographically structured. Results demonstrated that cork oak populations have undergone a genetic drift geographically consistent with the Oligocene and Miocene break-up events of the European-Iberian continental margin and suggested that they have persisted in a number of separate microplates, currently found in Tunisia, Sardinia, Corsica, and Provence, without detectable chloroplast DNA modifications for a time span of over 15 million years. A similar distribution pattern of mitochondrial DNA of Pinus pinaster supports the hypothesis of such long-term persistence, in spite of Quaternary climate oscillations and of isolation due to insularity, and suggests that part of the modern geographical structure of Mediterranean populations may be traced back to the Tertiary history of taxa.

  12. Differential DNA Methylation Patterns Are Related to Phellogen Origin and Quality of Quercus suber Cork.

    Science.gov (United States)

    Inácio, Vera; Barros, Pedro M; Costa, Augusta; Roussado, Cristóvão; Gonçalves, Elsa; Costa, Rita; Graça, José; Oliveira, M Margarida; Morais-Cecílio, Leonor

    2017-01-01

    DNA methylation is thought to influence Quercus suber cork quality, which is the main constraint for its economic valorisation. However, a deep knowledge of the cytosine methylation patterns disclosing the epigenetic variability of trees with different cork quality types is totally missing. This study investigates the hypothesis that variations in DNA methylation contribute to differences in cork cellular characteristics directly related to original or traumatic phellogen activity. We used MSAPs (Methylation Sensitive Amplified Polymorphism) to assess DNA methylation patterns of cork and leaf tissues of Q. suber adult trees growing in three cork oak stands. The relationship between the detected polymorphisms and the diversity of cork quality traits was explored by a marker-trait analysis focusing on the most relevant quality characteristics. Populations differed widely in cork quality, but only slightly in degree of epigenetic differentiation. Four MSAP markers (1.3% of the total) were significantly associated with the most noteworthy quality traits: wood inclusions (nails) and porosity. This evidence supports the potential role of cytosine methylation in the modulation of differential phellogen activity either involved in localized cell death or in pore production, resulting in different cork qualities. Although, the underlying basis of the methylation polymorphism of loci affecting cork quality traits remain unclear, the disclosure of markers statistically associated with cork quality strengthens the potential role of DNA methylation in the regulation of these traits, namely at the phellogen level.

  13. Characterization of the responses of cork oak (Quercus suber) to iron deficiency.

    Science.gov (United States)

    Gogorcena, Y; Molias, N; Larbi, A; Abadía, J; Abadía, A

    2001-12-01

    We studied responses of cork oak (Quercus suber L.) to iron (Fe) deficiency by comparing seedlings grown hydroponically in nutrient solution with and without Fe. Seedlings grown without Fe developed some responses typical of the Strategy I group of Fe-efficient plants, including two- and fourfold increases in plasma membrane ferric chelate reductase activity of root tips after 2 and 4 weeks of culture in the absence of Fe, respectively. Moreover, seedlings grown hydroponically for 2 weeks without Fe caused marked decreases in the pH of the nutrient solution, indicating that root plasma membrane ATPase activity was induced by Fe deficiency. Iron deficiency also caused marked decreases in leaf chlorophyll and carotenoid concentrations, and chlorophyll concentrations were decreased more than carotenoid concentrations. Iron deficiency resulted in an 8% decrease in the dark-adapted efficiency of photosystem II and a 43% decrease in efficiency of photosystem II at steady-state photosynthesis. No major root morphological changes were observed in seedlings grown without Fe, although seedlings grown in Fe-deficient nutrient solution had light-colored roots in contrast to the dark brown color of control roots.

  14. 5 CFR 630.1203 - Leave entitlement.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Leave entitlement. 630.1203 Section 630.1203 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS ABSENCE AND LEAVE Family and Medical Leave § 630.1203 Leave entitlement. (a) An employee shall be entitled to...

  15. Wettability, polarity, and water absorption of holm oak leaves: effect of leaf side and age.

    Science.gov (United States)

    Fernández, Victoria; Sancho-Knapik, Domingo; Guzmán, Paula; Peguero-Pina, José Javier; Gil, Luis; Karabourniotis, George; Khayet, Mohamed; Fasseas, Costas; Heredia-Guerrero, José Alejandro; Heredia, Antonio; Gil-Pelegrín, Eustaquio

    2014-09-01

    Plant trichomes play important protective functions and may have a major influence on leaf surface wettability. With the aim of gaining insight into trichome structure, composition, and function in relation to water-plant surface interactions, we analyzed the adaxial and abaxial leaf surface of holm oak (Quercus ilex) as a model. By measuring the leaf water potential 24 h after the deposition of water drops onto abaxial and adaxial surfaces, evidence for water penetration through the upper leaf side was gained in young and mature leaves. The structure and chemical composition of the abaxial (always present) and adaxial (occurring only in young leaves) trichomes were analyzed by various microscopic and analytical procedures. The adaxial surfaces were wettable and had a high degree of water drop adhesion in contrast to the highly unwettable and water-repellent abaxial holm oak leaf sides. The surface free energy and solubility parameter decreased with leaf age, with higher values determined for the adaxial sides. All holm oak leaf trichomes were covered with a cuticle. The abaxial trichomes were composed of 8% soluble waxes, 49% cutin, and 43% polysaccharides. For the adaxial side, it is concluded that trichomes and the scars after trichome shedding contribute to water uptake, while the abaxial leaf side is highly hydrophobic due to its high degree of pubescence and different trichome structure, composition, and density. Results are interpreted in terms of water-plant surface interactions, plant surface physical chemistry, and plant ecophysiology.

  16. Nutrient resorption from seagrass leaves

    NARCIS (Netherlands)

    Stapel, J.; Hemminga, M.A.

    1997-01-01

    The resorption of nutrients (C, N and P) from senescent leaves of six seagrass species from nine different locations in tropical (Indonesia and Kenya), Mediterranean (Spain) and temperate (The Netherlands) regions has been investigated. Resorption was quantitatively assessed by calculating the diffe

  17. Watch out for the leaves!

    CERN Document Server

    HSE Unit

    2013-01-01

    Now that autumn is here, dead leaves falling from the trees form a colourful carpet that is pleasing to the eye. However, the reality is less pleasant for pedestrians, since these leaves increase the risk of slipping and falling, especially when the ground is wet.   These conditions are also hazardous for two- and four-wheeled vehicles, whose grip on the ground can be severely reduced, thereby increasing the risk of them skidding out of control. Cyclists are among the most vulnerable road users when faced with these hazards. It is therefore essential to be alert to the dangers, which can be lessened by taking a few simple precautions such as moderating your speed and wearing suitable shoes. We also invite you to notify the Service Desk if you notice a road or pavement where there is a high concentration of dead leaves. The CERN Roads and Drainage Service will then ensure that the leaves are cleared in order to reduce the risk of accidents in the area.

  18. 5 CFR 630.1114 - Accrual of leave while using donated annual leave.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Accrual of leave while using donated annual leave. 630.1114 Section 630.1114 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS ABSENCE AND LEAVE Emergency Leave Transfer Program § 630.1114 Accrual of leave...

  19. The macrofungal diversity and community of Atlantic oak (Quercus petraea and Q. robur forests in Ireland

    Directory of Open Access Journals (Sweden)

    Harrington, Thomas J.

    2012-06-01

    Full Text Available The oak species Quercus petraea and Q. Robur are dominant canopy tree species of native deciduous forests in Ireland and coastal regions of Western Europe. These forests are typically plant species-rich, and can also have a rich fungal flora. This survey examined macrofungi found in five native oak sites across Ireland over three years. Overall, 94 macrofungal species belonging to 39 genera were discovered with Mycena, Lactarius, Russula and Cortinarius the most species-rich genera. The species accumulation curve did not show signs of levelling off, indicating that more sampling would reveal more new species. Species richness estimation using the Chao2 estimator indicated that up to 135 species may be present across all of our plots, with individual plots receiving estimates from 19 to 61 species per plot. Sampled-based rarefaction analysis showed no significant differences in macrofungal species richness between our plots. The five most common species were Laccaria amethystina, L. laccata, Stereum hirsutum, Armillaria mellea and Cortinarius flexipes. Comparisons of the results with results from oak forests in similar regions found that the communities in Great Britain were most similar to those found in Ireland. There were some key oak forest distinguishing fungal species from the family Boletaceae lacking from Irish oak forests. It is hypothesised that the historic deforestation of Ireland, caused a reduction of suitable habitats for Irish oak associated macrofungi, leading to the unspecific mycota found in the oak forests of this study. The threats to Atlantic oak forests in Ireland are briefly discussed.Las especies de Quercus petraea y Q. Robur se encuentran en bosques de Irlanda y regiones de influencia atlántica de Europa Occidental. Estos bosques, típicamente ricos en especies de plantas, presentan una abundante micobiota. Este estudio examina la diversidad de macromicetes en cinco bosques naturales de roble en Irlanda durante un

  20. The negative impact of intentionally introduced Quercus rubra L. on a forest community

    Directory of Open Access Journals (Sweden)

    Beata Woziwoda

    2014-03-01

    Full Text Available Some alien woody species used in commercial forestry become invasive and, as invaders, cause major problems in natural and semi-natural ecosystems. However, the deliberate introduction of aliens can bring unintended negative changes also within areas of their cultivation. This paper presents the effects of the intentional introduction of the North-American Quercus rubra in European mixed Scots pine-Pedunculate oak forests (POFs: Querco roboris-Pinetum (W. Mat. 1981 J. Mat. 1988. Phytosociological data from field research combined with GIS data analysis of the current distribution of Northern Red oak in the studied habitat were used to determine the composition and structure of forest communities in plots with and without Q. rubra participation.  The results show that Q. rubra significantly reduces native species richness and abundance, both in old-growth and in secondary (post-agricultural forests. Not one resident vascular plant benefits from the introduction of Northern Red oak and only a few are able to tolerate its co-occurrence. The natural restocking of all native woody species is also strongly limited by this alien tree.  The introduction of Northern Red oak significantly limits the environmental functions of the POF ecosystem and weakens its economic and social aspects. However, its further cultivation is justified from an economic point of view, as the essential function of the studied forests is commercial timber production, and the introduction of this fast growing alien tree supports the provisioning ecosystem services. A clear description of the level of trade-off between the accepted negative and positive effects of the introduction of Q. rubra on forest ecosystem services requires further interdisciplinary studies.

  1. Continuous Spectrum LEDs Promote Seedling Quality Traits and Performance of Quercus ithaburensis var. macrolepis.

    Science.gov (United States)

    Smirnakou, Sonia; Ouzounis, Theoharis; Radoglou, Kalliopi M

    2017-01-01

    Regulation of the growth, development, and quality of plants by the control of light quality has attracted extensive attention worldwide. The aim of this study was to examine the effects of continuous LED spectrum for indoor plant pre-cultivation and to investigate the morphological and physiological responses of a common broadleaved tree species in Mediterranean environment, Quercus ithaburensis var. macrolepis at seedling developmental stage. Thus, the seedlings were pre-cultivated for 28 days, under five different LED light qualities: (1) Fluorescent (FL) as control light (2) L20AP67 (high in green and moderate in far-red), (3) AP673L (high in green and red), (4) G2 (highest in red and far-red), AP67 (high in blue, red, and far-red), and (5) NS1 (highest in blue and green and lowest in far-red) LEDs. Further examination was held at the nursery for 1 year, on several seedling quality traits. Indeed, AP67 and AP673L triggered higher leaf formation, while L20AP67 positively affected seedling shoot development. NS1 and AP67 LED pre-cultivated seedlings showed significantly higher root fibrosity than those of FL light. Furthermore, NS1 and AP673L LEDs induced fourfold increase on seedling root dry weight than FL light. Hence, evaluating the seedling nursery performance attributes, most of those photomorphogenetic responses previously obtained were still detectable. Even more so, LED pre-cultivated seedlings showed higher survival and faster growth indicating better adaptation even under natural light conditions, a fact further reinforced by the significantly higher Dickson's quality index acquired. In conclusion, the goal of each nursery management program is the production of high quality seedlings with those desirable traits, which in turn satisfy the specific needs for a particular reforestation site. Thus, the enhanced oak seedling quality traits formed under continuous LEDs spectrum especially of NS1 and AP673L pre-cultivation may potentially fulfill this goal.

  2. Addressing post-transplant summer water stress in Pinus pinea and Quercus ilex seedlings

    Directory of Open Access Journals (Sweden)

    Pardos M

    2015-06-01

    Full Text Available In central Spain, post-transplant water stress produces high seedling mortality after the first summer following outplanting. Our study was designed to determine whether survival and performance of outplanted stone pine (Pinus pinea and holm oak (Quercus ilex seedlings in a burned area could be improved by summer irrigation and mulching and to identify whether there is a species-specific adaptive capacity to respond to treatment and environment. Seedlings were outplanted in March 2011 in 200 planting holes in an area of 1.1 ha. Mulch was added in June; irrigation started in July and was repeated every week until mid-September. The severity of the 2011 summer drought constrained growth rates and photosynthetic characteristics, mainly in the non-irrigated seedlings, whose survival at the end of the year after planting was approximately 2.5%. Stone pine and holm oak seedlings responded more to irrigation than to mulching in terms of shoot growth, biomass and survival. Furthermore, stone pine seedlings were found to be more responsive to the partial alleviation of summer drought than holm oak seedlings. Irrigation alone produced similar results to those obtained when both irrigation and mulching were employed. In conclusion, first year summer irrigation should be considered as a planned adaptation measure in the management of outplanted Mediterranean ecosystems, because once a gravimetrically measured soil moisture level as low as 2% is achieved seedling survival and physiological performance can be guaranteed. However, the repercussions for the potential persistence of both species in the area will not only be related to the recurrence and intensity of summer droughts but also to drought duration.

  3. ECUACIONES ALOMÉTRICAS PARA ESTIMAR BIOMASA Y CARBONO EN Quercus magnoliaefolia

    Directory of Open Access Journals (Sweden)

    Jesús D. Gómez-Díaz

    2011-01-01

    Full Text Available En el ejido El Zapote de la Reserva de la Biosfera "Sierra de Huautla", estado de Morelos, México, se seleccionaron doce árboles de Quercus magnoliaefolia Née y se determinó su biomasa en la parte aérea. El modelo alométrico quedó expresado como: B = 0.0345 * DAP2.9334 en donde B es la biomasa (kg y DAP es el diámetro a la altura del pecho (cm, con un coeficiente de determinación (R2= 0.98; P<0.001. Adicionalmente, se estimó la biomasa mediante una regresión lineal múltiple que consideró el área basal (AB, la densidad específica de la madera (DEM y la altura de los árboles (H. Una alta proporción de la varianza de la biomasa fue explicada solamente por el área basal. La DEM y H no incrementaron significativamente la precisión de los modelos. El porcentaje promedio de carbono en los árboles de Q. magnoliaefolia fue de 47.14 con valores de 46.29 % para el fuste, 46.83 % para las ramas y 48.31 % para el follaje. La proporción promedio de los componentes de la especie estudiada fue de 2.5 % para el fuste, 27.8 % para las ramas y 9.6 % para el follaje.

  4. Indirect effects of precipitation variation on the decomposition process of Mongolian oak (Quercus mongolica) leaf litter

    Institute of Scientific and Technical Information of China (English)

    LI Xuefeng; HAN Shijie; ZHANG Yan

    2007-01-01

    The effect of precipitation variation on the chemistry of Mongolian oak(Quercus mongolica)leaf litters was examined by analyzing litters of Mongolia oak saplings under four precipitation gradients.The decomposing process of these leaf litters in the Mongolian oak dominated forest was assessed using litter bag method.Compared with the litters of the Mongolian oak saplings from the natural precipitation site(A),litters produced by Mongolian oak from the driest precipitation gradient(A450)had significantly higher concentrations of nitrogen(N),phosphorus(P)and potassium(K)while lower acid-insoluble fraction(A/F)concentration.The decomposition study showed that A450 exhibited significantly higher decomposition rate,mineralization rates of N,P and K as well as much shorter N and P net immobilization periods.On the contrary,litters produced by seedlings from wettest gradient(Ass0)showed a totally opposite pattern.Litters from saplings that received comparable precipitation(A650)to those at the natural site(A)had significantly higher N concentration and faster decomposition rate as well as release rates of N,P and K.The mass loss patterns for the four litter types fitted the exponential model and the decay constant(k)can be well predicted by initial AIF/N.During the decomposition period,N concentration was best related to the percentage of mass remaining of the litters with relatively higher AIF concentrations and lower N concentrations,but the percentage of mass remaining of litters with lower AIF concentrations and higher N concentrations correlates strongly with AIF concentration.Our study proved that changes in precipitation significantly altered the litter quality,and therefore indirectly changed the decay process of leaf litters.

  5. Lignin Composition and Structure Differs between Xylem, Phloem and Phellem in Quercus suber L.

    Science.gov (United States)

    Lourenço, Ana; Rencoret, Jorge; Chemetova, Catarina; Gominho, Jorge; Gutiérrez, Ana; del Río, José C.; Pereira, Helena

    2016-01-01

    The composition and structure of lignin in different tissues—phellem (cork), phloem and xylem (wood)—of Quercus suber was studied. Whole cell walls and their respective isolated milled lignins were analyzed by pyrolysis coupled with gas chromatography/mass spectrometry (Py-GC/MS), two-dimensional nuclear magnetic resonance spectroscopy (2D-NMR) and derivatization followed by reductive cleavage (DFRC). Different tissues presented varied p-hydroxyphenyl:guaiacyl:syringyl (H:G:S) lignin compositions. Whereas lignin from cork has a G-rich lignin (H:G:S molar ratio 2:85:13), lignin from phloem presents more S-units (H:G:S molar ratio of 1:58:41) and lignin from xylem is slightly enriched in S-lignin (H:G:S molar ratio 1:45:55). These differences were reflected in the relative abundances of the different interunit linkages. Alkyl-aryl ethers (β–O–4′) were predominant, increasing from 68% in cork, to 71% in phloem and 77% in xylem, as consequence of the enrichment in S-lignin units. Cork lignin was enriched in condensed structures such as phenylcoumarans (β-5′, 20%), dibenzodioxocins (5–5′, 5%), as corresponds to a lignin enriched in G-units. In comparison, lignin from phloem and xylem presented lower levels of condensed linkages. The lignin from cork was highly acetylated at the γ-OH of the side-chain (48% lignin acetylation), predominantly over G-units; while the lignins from phloem and xylem were barely acetylated and this occurred mainly over S-units. These results are a first time overview of the lignin structure in xylem, phloem (generated by cambium), and in cork (generated by phellogen), in agreement with literature that reports that lignin biosynthesis is flexible and cell specific. PMID:27833631

  6. Carbon storage in degraded cork oak (Quercus suber forests on flat lowlands in Morocco

    Directory of Open Access Journals (Sweden)

    Oubrahim H

    2016-02-01

    Full Text Available The present study aims to quantify the carbon stored in a degraded cork oak (Quercus suber L. ecosystem in the north west of Morocco, in view of potential management implications. To this end, carbon stocks were evaluated in the first 100 cm of the soil, the cork oak trees, and the understorey species (both above- and belowground. Results show that the total carbon stocks in the cork oak ecosystem ranges from 65 to 237 Mg ha-1 with a mean value of 121 Mg ha-1. The first 100 cm of the soil (including the forest floor represents the largest carbon pool (~51% of the total organic carbon of the ecosystem. Tree biomass (above- and belowground tissues of cork oak represents the second largest pool (47%, whereas the contribution of the understorey is less than 2%. Within the first 100 cm of the soil, over 87% of all the soil organic carbon is situated in the first 40 cm of the soil depth. The amount of carbon stored here ranges from 30 to 110 Mg ha-1and these organic carbon stocks vary considerably with the stand basal area of the cork oak (R2 = 0.82. In practice, the carbon stocks of the different pools considered are strongly correlated with the stand density of the cork oak stands. In the semi-arid forest ecosystems of our study, management prescriptions aiming at increasing the standing biomass of the cork oak should thus considerably contribute, both directly through tree biomass and indirectly through increased soil organic matter, to efficient carbon sequestration.

  7. Physiological function of insoluble dietary fiber prepared from exploded oak wood (Quercus mongolica).

    Science.gov (United States)

    Yang, Jae-Kyung; Choi, Myung-Suk; Kim, Chang-Joon; Shin, Yong-Seung; Han, Dae-Yong; Han, Sang-Woo; Lim, Bu-Kug; Lee, Jong-Yoon; Rhee, Soon-Jae; Kim, Eun-Hee; Kim, Gon-Sup

    2006-01-01

    This study investigated the production of insoluble dietary fiber using exploded and chemically treated oak wood (Quercus mongolica) and the physiological functions of prepared insoluble dietary fiber in laboratory animals. To produce high quality insoluble dietary fiber, the steam explosion treatment was performed at 25 kgf/cm2 pressure for 6 minutes. In the chemical analysis of insoluble dietary fiber, exploded oak wood was pretreated by 1% sodium hydroxide solution. The insoluble dietary fiber contained 7.6% residual lignin and 61.7% of alpha-cellulose. In order to compare the physiological functions of prepared insoluble dietary fiber with those of commercial insoluble dietary fiber, Sprague-Dawley male rats weighing 100 +/- 10 g were randomly assigned to one normal diet and five high cholesterol diets, containing 1% cholesterol. The high cholesterol diet groups were classified as the fiber-free diet (FF group), 5% commercial alpha-cellulose diet group (5C group), 10% commercial alpha-cellulose group (10C group), 5% insoluble dietary fiber group (5M group) and 10% insoluble dietary fiber group (10M group). Food intake, weight gain and food efficiency ratio in high cholesterol groups were significantly higher than those of the normal group, but there were no significant differences among the high cholesterol diet groups. In addition, there were no significant differences in the weights of liver, kidney and small intestine in insoluble dietary fiber-supplemented groups. Cecum weights in all insoluble dietary fiber groups were significantly higher than those of the FF group. There were no significant differences in the activities of the glutamic pyruvic transaminase (GPT) and glutamic oxaloacetic transaminase (GOT) among the insoluble dietary fiber-supplemented groups. In conclusion, the prepared insoluble dietary fiber and the commercially available insoluble fiber showed the same physiological effects. Moreover, the preparation method for the insoluble dietary

  8. Soil Respiration in Relation to Photosynthesis of Quercus mongolica Trees at Elevated CO2

    Science.gov (United States)

    Zhou, Yumei; Li, Mai-He; Cheng, Xu-Bing; Wang, Cun-Guo; Fan, A-Nan; Shi, Lian-Xuan; Wang, Xiu-Xiu; Han, Shijie

    2010-01-01

    Knowledge of soil respiration and photosynthesis under elevated CO2 is crucial for exactly understanding and predicting the carbon balance in forest ecosystems in a rapid CO2-enriched world. Quercus mongolica Fischer ex Ledebour seedlings were planted in open-top chambers exposed to elevated CO2 (EC = 500 µmol mol−1) and ambient CO2 (AC = 370 µmol mol−1) from 2005 to 2008. Daily, seasonal and inter-annual variations in soil respiration and photosynthetic assimilation were measured during 2007 and 2008 growing seasons. EC significantly stimulated the daytime soil respiration by 24.5% (322.4 at EC vs. 259.0 mg CO2 m−2 hr−1 at AC) in 2007 and 21.0% (281.2 at EC vs. 232.6 mg CO2 m−2 hr−1 at AC) in 2008, and increased the daytime CO2 assimilation by 28.8% (624.1 at EC vs. 484.6 mg CO2 m−2 hr−1 at AC) across the two growing seasons. The temporal variation in soil respiration was positively correlated with the aboveground photosynthesis, soil temperature, and soil water content at both EC and AC. EC did not affect the temperature sensitivity of soil respiration. The increased daytime soil respiration at EC resulted mainly from the increased aboveground photosynthesis. The present study indicates that increases in CO2 fixation of plants in a CO2-rich world will rapidly return to the atmosphere by increased soil respiration. PMID:21151897

  9. [Effects of light intensity on Quercus liaotungensis seed germination and seedling growth].

    Science.gov (United States)

    Yan, Xing-fu; Wang, Jian-li; Zhou, Li-biao

    2011-07-01

    This paper studied the effects of different shading (55.4%, 18.9%, 5.5%, 2.2%, 0.5% , and 0.3% natural sunlight) on the seed germination and seedling growth of Quercus liaotungensis. The seed germination rate and germination index were the highest (72.5% and 0.22, respectively) at 55.4% natural sunlight, declined with decreasing light intensity, and were the lowest (42.5% and 0.11, respectively) at 0.3% natural sunlight. Strong light had definite delaying effect on the germination. The index of germination vigor increased with decreasing light intensity, being the maximum at 0.5% natural sunlight. The delay of seed germination under strong light could be the selective tradeoff on varied seed fates. Strong light benefited the basal stem diameter and root system growth and dry mass accumulation of Q. liaotunensis seedling, but resulted in the minimum seedlings height (6.06 cm). Greater morphological plasticity was observed for the seedlings under different shading, which lent support to the higher adaptability of the seedlings to light environment. For example, the specific leaf area, specific shoot length, specific root length, and chlorophyll b and total chlorophyll contents were the maximum at 0.5% natural sunlight, being 142.57 cm2 x g(-1), 156.86 cm x g(-1), 271.87 cm x g(-1), 0.07 g x cm(-2), and 0.24 g x cm(-2), respectively, and the minimum at 55.4% natural sunlight, being 44.89 cm2 x g(-1), 52.84 cm x g(-1), 101.98 cm x g(-1), 0.04 g x cm(-2), and 0.15 g x cm(-2), respectively. The variation of the root/shoot ratio of Q. liaotungensis seedlings under different shading could be the effects of the combination of light intensity and water availability.

  10. Is thinning adequate for adapting old Quercus ilex coppices to climate change?

    Science.gov (United States)

    Rodriguez-Calcerrada, Jesus; Perez-Ramos, Ignacio-Manuel; Ourcival, Jean-Marc; Limousin, Jean-Marc; Misson, Laurent; Joffre, Richard; Rambal, Serge; Martin, Nicolas

    2010-05-01

    Future climatic scenarios call for an increasing involvement of management for forest preservation, but little is known on how forestry practices will benefit stands in facing variation of climatic components. We investigated how thinning affected tree responses to six years of continued throughfall reduction in a Mediterranean Quercus ilex stand formerly managed as a coppice. Thinned plots (≈33% basal area removal) and unthinned plots were subsequently subject to either throughfall exclusion (≈28% throughfall reduction) or normal rainfall. Stem-diameter growth, stem survival and seed production were monitored over the following six years; the presence, abundance and growth of new sprouts were measured in the last year. In the absence of thinning, throughfall exclusion accelerated the mortality of small stems, reduced the production of viable acorns and stimulated the emergence of new sprouts. Throughfall exclusion did not have any effect on stem growth. Rather, trees responded to the imposed reduction on throughfall by decreasing the leaf area and thus by minimizing the risk of xylem cavitation. Thinning reduced the mortality of stems, enhanced the diameter growth of residual stems and caused a profuse emission of resprouts. Thinning also increased total seed production but the crop had a large proportion of aborted seeds. Overall, the results point out to a better disposition of thinned Q. ilex coppice stands to cope with future (probably longer and more intense) droughts, at least in the short term. The reduction in standing dead biomass reduces the probability of occurrence of wildfires while the increase in growth and probably carbon reserves may help trees to overcome dry summers where CO2 assimilation is strongly limited. The mere felling of dominated and diseased stems, however, will probably not result in any longer-term advantage derived from seed regeneration without any further silvicultural treatment that promote seedling recruitment.

  11. Comparative transcriptomic analysis of male and female flowers of monoecious Quercus suber

    Directory of Open Access Journals (Sweden)

    Margarida eRocheta

    2014-11-01

    Full Text Available Monoecious species provide a comprehensive system to study the developmental programs underlying the establishment of female and male organs in unisexual flowers. However, molecular resources for most monoecious non-model species are limited, hampering our ability to study the molecular mechanisms involved in flower development of these species. The objective of this study was to identify differentially expressed genes during the development of male and female flowers of the monoecious species Quercus suber, an economically important Mediterranean tree. Total RNA was extracted from different developmental stages of Q. suber flowers. Non-normalised cDNA libraries of male and female flowers were generated using 454 pyrosequencing technology producing a total of 962,172 high-quality reads with an average length of 264 nucleotides. The assembly of the reads resulted in 14,488 contigs for female libraries and 10,438 contigs for male libraries. Comparative analysis of the transcriptomes revealed genes differentially expressed in early and late stages of development of female and male flowers, some of which have been shown to be involved in pollen development, in ovule formation and in flower development of other species with a monoecious, dioecious or hermaphroditic sexual system. Moreover, we found differentially expressed genes that have not yet been characterised and others that have not been previously shown to be implicated in flower development. This transcriptomic analysis constitutes a major step towards the characterisation of the molecular mechanisms involved in flower development in a monoecious tree with a potential contribution towards the knowledge of conserved developmental mechanisms in other species.

  12. Comparative transcriptomic analysis of male and female flowers of monoecious Quercus suber.

    Science.gov (United States)

    Rocheta, Margarida; Sobral, Rómulo; Magalhães, Joana; Amorim, Maria I; Ribeiro, Teresa; Pinheiro, Miguel; Egas, Conceição; Morais-Cecílio, Leonor; Costa, Maria M R

    2014-01-01

    Monoecious species provide a comprehensive system to study the developmental programs underlying the establishment of female and male organs in unisexual flowers. However, molecular resources for most monoecious non-model species are limited, hampering our ability to study the molecular mechanisms involved in flower development of these species. The objective of this study was to identify differentially expressed genes during the development of male and female flowers of the monoecious species Quercus suber, an economically important Mediterranean tree. Total RNA was extracted from different developmental stages of Q. suber flowers. Non-normalized cDNA libraries of male and female flowers were generated using 454 pyrosequencing technology producing a total of 962,172 high-quality reads with an average length of 264 nucleotides. The assembly of the reads resulted in 14,488 contigs for female libraries and 10,438 contigs for male libraries. Comparative analysis of the transcriptomes revealed genes differentially expressed in early and late stages of development of female and male flowers, some of which have been shown to be involved in pollen development, in ovule formation and in flower development of other species with a monoecious, dioecious, or hermaphroditic sexual system. Moreover, we found differentially expressed genes that have not yet been characterized and others that have not been previously shown to be implicated in flower development. This transcriptomic analysis constitutes a major step toward the characterization of the molecular mechanisms involved in flower development in a monoecious tree with a potential contribution toward the knowledge of conserved developmental mechanisms in other species.

  13. Lignin Composition and Structure Differs between Xylem, Phloem and Phellem in Quercus suber L.

    Science.gov (United States)

    Lourenço, Ana; Rencoret, Jorge; Chemetova, Catarina; Gominho, Jorge; Gutiérrez, Ana; Del Río, José C; Pereira, Helena

    2016-01-01

    The composition and structure of lignin in different tissues-phellem (cork), phloem and xylem (wood)-of Quercus suber was studied. Whole cell walls and their respective isolated milled lignins were analyzed by pyrolysis coupled with gas chromatography/mass spectrometry (Py-GC/MS), two-dimensional nuclear magnetic resonance spectroscopy (2D-NMR) and derivatization followed by reductive cleavage (DFRC). Different tissues presented varied p-hydroxyphenyl:guaiacyl:syringyl (H:G:S) lignin compositions. Whereas lignin from cork has a G-rich lignin (H:G:S molar ratio 2:85:13), lignin from phloem presents more S-units (H:G:S molar ratio of 1:58:41) and lignin from xylem is slightly enriched in S-lignin (H:G:S molar ratio 1:45:55). These differences were reflected in the relative abundances of the different interunit linkages. Alkyl-aryl ethers (β-O-4') were predominant, increasing from 68% in cork, to 71% in phloem and 77% in xylem, as consequence of the enrichment in S-lignin units. Cork lignin was enriched in condensed structures such as phenylcoumarans (β-5', 20%), dibenzodioxocins (5-5', 5%), as corresponds to a lignin enriched in G-units. In comparison, lignin from phloem and xylem presented lower levels of condensed linkages. The lignin from cork was highly acetylated at the γ-OH of the side-chain (48% lignin acetylation), predominantly over G-units; while the lignins from phloem and xylem were barely acetylated and this occurred mainly over S-units. These results are a first time overview of the lignin structure in xylem, phloem (generated by cambium), and in cork (generated by phellogen), in agreement with literature that reports that lignin biosynthesis is flexible and cell specific.

  14. Regulation of transpirational water loss in Quercus suber trees in a Mediterranean-type ecosystem.

    Science.gov (United States)

    Otieno, D O; Schmidt, M W T; Kurz-Besson, C; Lobo Do Vale, R; Pereira, J S; Tenhunen, J D

    2007-08-01

    Sap flux density in branches, leaf transpiration, stomatal conductance and leaf water potentials were measured in 16-year-old Quercus suber L. trees growing in a plantation in southern Portugal to understand how evergreen Mediterranean trees regulate water loss during summer drought. Leaf specific hydraulic conductance and leaf gas exchange were monitored during the progressive summer drought to establish how changes along the hydraulic pathway influence shoot responses. As soil water became limiting, leaf water potential, stomatal conductance and leaf transpiration declined significantly. Predawn leaf water potential reflected soil water potential measured at 1-m depth in the rhizospheres of most trees. The lowest predawn leaf water potential recorded during this period was -1.8 MPa. Mean maximum stomatal conductance declined from 300 to 50 mmol m(-2) s(-1), reducing transpiration from 6 to 2 mmol m(-2) s(-1). Changes in leaf gas exchange were attributed to reduced soil water availability, increased resistances along the hydraulic pathway and, hence, reduced leaf water supply. There was a strong coupling between changes in soil water content and stomatal conductance as well as between stomatal conductance and leaf specific hydraulic conductance. Despite significant seasonal differences among trees in predawn leaf water potential, stomatal conductance, leaf transpiration and leaf specific hydraulic conductance, there were no differences in midday leaf water potentials. The strong regulation of changes in leaf water potential in Q. suber both diurnally and seasonally is achieved through stomatal closure, which is sensitive to changes in both liquid and vapor phase conductance. This sensitivity allows for optimization of carbon and water resource use without compromising the root-shoot hydraulic link.

  15. Lignin composition and structure differs between xylem, phloem and phellem in Quercus suber L.

    Directory of Open Access Journals (Sweden)

    Ana Lourenço

    2016-10-01

    Full Text Available The composition and structure of lignin in different tissues - phellem (cork, phloem and xylem (wood - of Quercus suber was studied. Whole cell walls and their respective isolated milled lignins were analyzed by pyrolysis coupled with gas chromatography/mass spectrometry (Py-GC/MS, two-dimensional nuclear magnetic resonance spectroscopy (2D-NMR and derivatization followed by reductive cleavage (DFRC. Different tissues presented varied p-hydroxyphenyl:guaiacyl:syringyl (H:G:S lignin compositions. Whereas lignin from cork has a G-rich lignin (H:G:S molar ratio 2:85:13, lignin from phloem presents more S-units (H:G:S molar ratio of 1:58:41 and lignin from xylem is slightly enriched in S-lignin (H:G:S molar ratio 1:45:55. These differences were reflected in the relative abundances of the different interunit linkages. Alkyl-aryl ethers (β–O–4´ were predominant, increasing from 68% in cork, to 71% in phloem and 77% in xylem, as consequence of the enrichment in S-lignin units. Cork lignin was enriched in condensed structures such as phenylcoumarans (β-5´, 20%, dibenzodioxocins (5-5´, 5%, as corresponds to a lignin enriched in G-units. In comparison, lignin from phloem and xylem presented lower levels of condensed linkages. The lignin from cork was highly acetylated at the γ-OH of the side-chain (48% lignin acetylation, predominantly over G-units; while the lignins from phloem and xylem were barely acetylated and this occurred mainly over S-units. These results are a first time overview of the lignin structure in xylem, phloem (generated by cambium, and in cork (generated by phellogen, in agreement with literature that lignin biosynthesis is flexible and cell specific.

  16. Climate change effect on Betula (birch) and Quercus (oak) pollen seasons in the United States

    Science.gov (United States)

    Zhang, Yong; Bielory, Leonard; Georgopoulos, Panos G.

    2014-07-01

    Climatic change is expected to affect the spatiotemporal patterns of airborne allergenic pollen, which has been found to act synergistically with common air pollutants, such as ozone, to cause allergic airway disease (AAD). Observed airborne pollen data from six stations from 1994 to 2011 at Fargo (North Dakota), College Station (Texas), Omaha (Nebraska), Pleasanton (California), Cherry Hill and Newark (New Jersey) in the US were studied to examine climate change effects on trends of annual mean and peak value of daily concentrations, annual production, season start, and season length of Betula (birch) and Quercus (oak) pollen. The growing degree hour (GDH) model was used to establish a relationship between start/end dates and differential temperature sums using observed hourly temperatures from surrounding meteorology stations. Optimum GDH models were then combined with meteorological information from the Weather Research and Forecasting (WRF) model, and land use land coverage data from the Biogenic Emissions Land use Database, version 3.1 (BELD3.1), to simulate start dates and season lengths of birch and oak pollen for both past and future years across the contiguous US (CONUS). For most of the studied stations, comparison of mean pollen indices between the periods of 1994-2000 and 2001-2011 showed that birch and oak trees were observed to flower 1-2 weeks earlier; annual mean and peak value of daily pollen concentrations tended to increase by 13.6 %-248 %. The observed pollen season lengths varied for birch and for oak across the different monitoring stations. Optimum initial date, base temperature, and threshold GDH for start date was found to be 1 March, 8 °C, and 1,879 h, respectively, for birch; 1 March, 5 °C, and 4,760 h, respectively, for oak. Simulation results indicated that responses of birch and oak pollen seasons to climate change are expected to vary for different regions.

  17. BVOC emissions from English oak (Quercus robur) and European beech (Fagus sylvatica) along a latitudinal gradient

    Science.gov (United States)

    van Meeningen, Ylva; Schurgers, Guy; Rinnan, Riikka; Holst, Thomas

    2016-11-01

    English oak (Quercus robur) and European beech (Fagus sylvatica) are amongst the most common tree species growing in Europe, influencing the annual biogenic volatile organic compound (BVOC) budget in this region. Studies have shown great variability in the emissions from these tree species, originating from both genetic variability and differences in climatic conditions between study sites. In this study, we examine the emission patterns for English oak and European beech in genetically identical individuals and the potential variation within and between sites. Leaf scale BVOC emissions, net assimilation rates and stomatal conductance were measured at the International Phenological Garden sites of Ljubljana (Slovenia), Grafrath (Germany) and Taastrup (Denmark). Sampling was conducted during three campaigns between May and July 2014. Our results show that English oak mainly emitted isoprene whilst European beech released monoterpenes. The relative contribution of the most emitted compounds from the two species remained stable across latitudes. The contribution of isoprene for English oak from Grafrath and Taastrup ranged between 92 and 97 % of the total BVOC emissions, whilst sabinene and limonene for European beech ranged from 30.5 to 40.5 and 9 to 15 % respectively for all three sites. The relative contribution of isoprene for English oak at Ljubljana was lower (78 %) in comparison to the other sites, most likely caused by frost damage in early spring. The variability in total leaf-level emission rates from the same site was small, whereas there were greater differences between sites. These differences were probably caused by short-term weather events and plant stress. A difference in age did not seem to affect the emission patterns for the selected trees. This study highlights the significance of within-genotypic variation of BVOC emission capacities for English oak and European beech, the influence of climatic variables such as temperature and light on emission

  18. Associations between growth, wood anatomy, carbon isotope discrimination and mortality in a Quercus robur forest.

    Science.gov (United States)

    Levanic, Tom; Cater, Matjaz; McDowell, Nate G

    2011-03-01

    Observations of forest mortality are increasing globally, but relatively little is known regarding the underlying mechanisms driving these events. Tree rings carry physiological signatures that may be used as a tool for retrospective analyses. We capitalized on a local soil water drainage event in 1982 that resulted in increased mortality within a stand of oak trees (Quercus robur), to examine the underlying physiological patterns associated with survival and death in response to soil water limitations. Pre-dawn water potentials showed more negative values for trees in the process of dying compared with those that survived. We used tree rings formed over the 123 years prior to mortality to estimate productivity from basal area increment (BAI, mm(2)), multiple xylem hydraulic parameters via anatomical measurements and crown-level gas exchange via carbon isotope discrimination (Δ, ‰). Oaks that died had significantly higher BAI values than trees that survived until the drainage event, after which the BAI of trees that died declined dramatically. Hydraulic diameter and conductivity of vessels in trees that died were higher than in surviving trees until the last 5 years prior to mortality, at which time both groups had similar values. Trees that died had consistently lower Δ values than trees that survived. Therefore, tree mortality in this stand was associated with physiological differences prior to the onset of soil water reduction. We propose that trees that died may have been hydraulically underbuilt for dry conditions, which predisposes them to severe hydraulic constraints and subsequent mortality. Measurements of above-ground/below-ground dry mass partitioning will be critical to future tests of this hypothesis. Based on these results, it is probable that pedunculate oak trees will experience greater future mortality if climate changes cause more severe droughts than the trees have experienced previously.

  19. Quercus suber range dynamics by ecological niche modelling: from the Last Interglacial to present time

    Science.gov (United States)

    Vessella, Federico; Simeone, Marco Cosimo; Schirone, Bartolomeo

    2015-07-01

    Ecological Niche Modelling (ENM) is widely used to depict species potential occurrence according to environmental variables under different climatic scenarios. We tested the ENM approach to infer past range dynamics of cork oak, a keystone species of the Mediterranean Biome, from 130 ka to the present time. Hindcasting implications would deal with a better species risk assessment and conservation management for the future. We modelled present and past occurrence of cork oak using seven ENM algorithms, starting from 63,733 spatially unique presence points at 30 arc-second resolution. Fourteen environmental variables were used and four time slices were considered (Last Interglacial, Last Glacial Maximum, mid-Holocene and present time). A threshold-independent evaluation of the goodness-of-fit of the models was evaluated by means of ROC curve and fossil or historical evidences were used to validate the results. Four weighted average maps depicted the dynamics of area suitability for cork oak in the last 130 ka. The derived species autoecology allowed its long-term occurrence in the Mediterranean without striking range reduction or shifting. Fossil and historical post-processing validation support the modelled past spatial extension and a neglected species presence at Levantine until the recent time. Despite the severe climatic oscillation since the Last Glacial Maximum, cork oak potential distribution area experienced limited range changes, confirming its strong link with the Mediterranean Basin. The ecological amplitude of Quercus suber could be therefore adopted as a reference to trace the Mediterranean bioclimate area. A better knowledge of the past events of Mediterranean vegetation, a wider range of study species and environmental determinants are essential to inform us about its current state, its sensitivity to human impact and the potential responses to future changes.

  20. [Effects of simulated acid rain on Quercus glauca seedlings photosynthesis and chlorophyll fluorescence].

    Science.gov (United States)

    Li, Jia; Jiang, Hong; Yu, Shu-quan; Jiang, Fu-wei; Yin, Xiu-min; Lu, Mei-juan

    2009-09-01

    Taking the seedlings of Quercus glauca, a dominant evergreen broadleaf tree species in subtropical area, as test materials, this paper studied their photosynthesis, chlorophyll fluorescence, and chlorophyll content under effects of simulated acid rain with pH 2.5, 4.0, and 5.6 (CK). After 2-year acid rain stress, the net photosynthetic rate of Q. glauca increased significantly with decreasing pH of acid rain. The acid rain with pH 2.5 and 4.0 increased the stomatal conductance and transpiration rate, and the effect was more significant under pH 2.5. The intercellular CO2 concentration decreased in the order of pH 2.5 > pH 5.6 > pH 4.0. The maximum photosynthetic rate, light compensation point, light saturation point, and dark respiration rate were significantly higher under pH 2.5 and 4.0 than under pH 5.6, while the apparent quantum yield was not sensitive to acid rain stress. The maximal photochemical efficiency of PS II and the potential activity of PS II under pH 2.5 and 4.0 were significantly higher than those under pH 5.6. The relative chlorophyll content was in the order of pH 2.5 > pH 5.6 > pH 4.0, and there was a significant difference between pH 2.5 and 4.0. All the results suggested that the photosynthesis and chlorophyll fluorescence of Q. glauca increased under the effects of acid rain with pH 2.5 and 4.0, and the acid rain with pH 2.5 had more obvious effects.

  1. Climate change effect on Betula (birch) and Quercus (oak) pollen seasons in the United States.

    Science.gov (United States)

    Zhang, Yong; Bielory, Leonard; Georgopoulos, Panos G

    2014-07-01

    Climatic change is expected to affect the spatiotemporal patterns of airborne allergenic pollen, which has been found to act synergistically with common air pollutants, such as ozone, to cause allergic airway disease (AAD). Observed airborne pollen data from six stations from 1994 to 2011 at Fargo (North Dakota), College Station (Texas), Omaha (Nebraska), Pleasanton (California), Cherry Hill and Newark (New Jersey) in the US were studied to examine climate change effects on trends of annual mean and peak value of daily concentrations, annual production, season start, and season length of Betula (birch) and Quercus (oak) pollen. The growing degree hour (GDH) model was used to establish a relationship between start/end dates and differential temperature sums using observed hourly temperatures from surrounding meteorology stations. Optimum GDH models were then combined with meteorological information from the Weather Research and Forecasting (WRF) model, and land use land coverage data from the Biogenic Emissions Land use Database, version 3.1 (BELD3.1), to simulate start dates and season lengths of birch and oak pollen for both past and future years across the contiguous US (CONUS). For most of the studied stations, comparison of mean pollen indices between the periods of 1994-2000 and 2001-2011 showed that birch and oak trees were observed to flower 1-2 weeks earlier; annual mean and peak value of daily pollen concentrations tended to increase by 13.6%-248%. The observed pollen season lengths varied for birch and for oak across the different monitoring stations. Optimum initial date, base temperature, and threshold GDH for start date was found to be 1 March, 8 °C, and 1,879 h, respectively, for birch; 1 March, 5 °C, and 4,760 h, respectively, for oak. Simulation results indicated that responses of birch and oak pollen seasons to climate change are expected to vary for different regions.

  2. Influence of pericarp, cotyledon and inhibitory substances on sharp tooth oak (Quercus aliena var. acuteserrata germination.

    Directory of Open Access Journals (Sweden)

    Yan Liu

    Full Text Available In order to explore the mechanism of delayed and uneven germination in sharp tooth oak (Quercus aliena var. acuteserrata (STO, mechanical scarification techniques were used to study STO root and shoot germination and growth. The techniques used were: removing cup scar (RS, removing the pericarp (RP, and cutting off 1/2 (HC and 2/3 (TC cotyledons. Germination percentage and root and shoot length for Chinese cabbage (Beassica pekinensis seeds (CCS were also investigated for CCS cultivated in a Sanyo growth cabinet watered by distilled water and 80% methanol extracts from the acorn embryo, cotyledon and pericarp with concentrations of 1.0 g, 0.8 g, 0.6 g and 0.4 g dry acorn weight per ml methanol. The results showed that the majority of roots and shoots from acorns with RP and HC treatment emerged two weeks earlier, more simultaneously, and their total emergencies were more than 46% and 28% higher, respectively. TC accelerated root and shoot emergence time and root length, but root and shoot germination rate and shoot height had no significant difference from the control. Positive consequences were not observed on all indices of RS treatment. The germination rates of CCS watered by 1.0 g · ml(-1 methanol extracts from the embryo and cotyledon were significantly lower than those from the pericarp, and all concentrations resulted in decreased growth of root and shoot. Methanol extracts from pericarp significantly reduced root length of CCS, but presented little response in germination percentage and shoot length. The inhibitory effect was gradually increased with the increasing concentration of the methanol extract. We conclude that both the mechanical restriction of the pericarp and the presence of germination inhibitors in the embryo, cotyledon and pericarp are the causes for delayed and asynchronous germination of STO acorns.

  3. Phenolic compounds and fatty acids from acorns (Quercus spp.), the main dietary constituent of free-ranged Iberian pigs.

    Science.gov (United States)

    Cantos, Emma; Espín, Juan Carlos; López-Bote, Clemente; de la Hoz, Lorenzo; Ordóñez, Juan A; Tomás-Barberán, Francisco A

    2003-10-08

    The aim of the present work was to identify and quantify the phenolic compounds and fatty acids in acorns from Quercus ilex, Quercus rotundifolia, and Quercus suber. The concentration of oleic acid was >63% of total fatty acids in all cases, followed by palmitic and linoleic acids at similar concentrations (12-20%). The concentrations of alpha-tocopherol in Q. rotundifolia, Q. ilex, and Q. suber were 19, 31, and 38 mg/kg of dry matter (DM), respectively, whereas the concentrations of gamma-tocopherol were 113, 66, and 74 mg/kg of DM, respectively. Thirty-two different phenolic compounds were distinguished. All of them were gallic acid derivatives, in the form of either galloyl esters of glucose, combinations of galloyl and hexahydroxydiphenoyl esters of glucose, tergallic O- or C-glucosides, or ellagic acid derivatives. Several tergallic acid C-glucosides were also present in the extracts obtained from Q. suber. Acorns from Q. ilex and Q. rotundifolia showed similar polyphenol patterns mainly with gallic acid-like spectra. Chromatograms of Q. suber showed mainly polyphenols with ellagic acid-like spectra. Valoneic acid dilactone was especially abundant in Q. suber skin. The contribution of skin to the total phenolics of the acorn was relatively small in Q. rotundifolia and Q. ilex but relatively high in Q. suber. Skin extracts from Q. suber, Q. rotundifolia, and Q. ilex showed 1.3, 1.4, and 1.0 antioxidant efficiencies, respectively (compared to that of butylhydroxyanisole). Endosperm extracts showed lower capacity to prevent lipid peroxidation than skin extracts.

  4. Rasgos funcionales en el género Quercus: estrategias adquisitivas frente a conservativas en el uso de recursos

    Directory of Open Access Journals (Sweden)

    E. G. de la Riva

    2014-01-01

    Full Text Available Las especies del género Quercus constituyen uno de los grupos más abundantes e importantes de plantas leñosas de la Península Ibérica, estando su distribución determinada por la disponibilidad de agua, el tipo de suelo y la historia del manejo. El conocimiento de la variación de sus características morfo-funcionales puede ayudarnos a comprender el grado de diversificación de las especies del mismo género y los mecanismos que controlan sus patrones de distribución. Los objetivos principales de este estudio son: (i analizar las relaciones existentes entre los diferentes rasgos funcionales dentro del género Quercus y testar cómo se ajustan a las estrategias de captación de recursos; y (ii comprobar si existe coordinación entre los rasgos medidos a nivel de hoja, tallo y raíz. El muestreo se llevó a cabo en Sierra Morena (Córdoba y la Sierra del Aljibe (Cádiz, cuantificándose rasgos funcionales claves a nivel de hoja, tallo, raíz, tamaño de planta y fisiología en cinco especies de Quercus (Q. canariensis, Q. coccifera, Q. faginea, Q. ilex y Q. suber. Los resultados muestran que las diferentes especies de Quercus presentan claros patrones en sus estrategias funcionales que están relacionados con su distribución, encontrando un gradiente desde especies más conservativas en el uso de recursos en condiciones de menor disponibilidad de agua a especies más adquisitivas en zonas más húmedas. A su vez, se aprecia una coordinación entre los patrones de rasgos funcionales encontrados a nivel de hoja, tallo y de raíz que apoya la existencia de un “espectro de economía” a nivel de la planta entera.

  5. Visible leaf injury in young trees of Fagus sylvatica L. and Quercus robur L. in relation to ozone uptake and ozone exposure. An Open-Top Chambers experiment in South Alpine environmental conditions

    Energy Technology Data Exchange (ETDEWEB)

    Gerosa, G. [Catholic University of Brescia, Department of Mathematics and Physics, Via dei Musei 41, 25125 Brescia (Italy); Marzuoli, R. [Catholic University of Brescia, Department of Mathematics and Physics, Via dei Musei 41, 25125 Brescia (Italy)], E-mail: riccardo.marzuoli@unicatt.it; Desotgiu, R.; Bussotti, F. [University of Florence, Department of Plant Biology, Piazzale delle Cascine 28, 50144 Florence (Italy); Ballarin-Denti, A. [Catholic University of Brescia, Department of Mathematics and Physics, Via dei Musei 41, 25125 Brescia (Italy)

    2008-03-15

    An Open-Top Chambers experiment on Fagus sylvatica and Quercus robur seedlings was conducted in order to compare the performance of an exposure-based (AOT40) and a flux-based approaches in predicting the appearance of ozone visible injuries on leaves. Three different ozone treatments (charcoal-filtered; non-filtered; and open plots) and two soil moisture treatments (watered and non-watered plots) were performed. A Jarvisian stomatal conductance model was drawn up and parameterised for both species and typical South Alpine environmental conditions, thus allowing the calculation of ozone stomatal fluxes for every treatment. A critical ozone flux level for the onset of leaf visible injury in beech was clearly identified between 32.6 and 33.6 mmol O{sub 3}m{sup -2}. In contrast, it was not possible to identify an exposure critical level using the AOT40 index. Water stress delayed the onset of the leaf visible injuries, but the flux-based approach was able to take it into account accurately. - Ozone fluxes are more accurate than AOT40 exposure index in predicting ozone visible foliar injury onset on beech seedlings in South Alpine environmental conditions.

  6. Sick Leave and Subjective Health Complaints

    OpenAIRE

    Tveito, Torill Helene

    2007-01-01

    The aims of this thesis were to identify risk factors for high levels of sick leave and investigate what – if anything – can be done to reduce sick leave. What is the role of “subjective health complaints”, coping, and psychosocial work factors in relation to sick leave, and to what extent do these factors and the sick leave relate to quality of life? Are there any interventions with a documented effect on sick leave in the literature? Is it possible to influence sick leave thr...

  7. Quantitative trait loci for resistance to two fungal pathogens in Quercus robur

    Science.gov (United States)

    Cécile Robin; Amira Mougou-Hamdane; Jean-Marc Gion; Antoine Kremer; Marie-Laure. Desprez-Loustau

    2012-01-01

    Powdery mildew, caused by Erysiphe alphitoides (Ascomycete), is the most frequent disease of oaks, which are also known to be host plants for Phytophthora cinnamomi (Oomycete), the causal agent of ink disease. Components of genetic resistance to these two pathogens, infecting either leaves or root and collar, were...

  8. Taphonomy of deciduous leaves and changes in the d13C signal after deposition in fresh water settings

    Science.gov (United States)

    Reimann, Simon; Roth-Nebelsick, Anita; Nebelsick, James; Grein, Michaela

    2016-04-01

    Carbon isotopic signals from fossil plant material are an important source of information for palaeoecology and palaeoclimatology. Usually, the 13C isotope is depleted in plant material, compared to the atmospheric 13C content, because 13C is discriminated against 12C during the process of photosynthesis. The degree of 13C discrimination depends on the photosynthetic pathway (C3, C4 and CAM) and is substantially affected by environmental factors (for example, water stress). Various plant material components, however, differ also with respect to their 13C content. It is generally assumed that the d13C signal found in fossil plants reflects that of the living plant to a sufficient degree. Obtaining information on possible alterations during the taphonomic process is, however, desirable. In this study, changes in d13C of deciduous leaves are monitored, from the living leaf still attached to the tree to leaves deposited in fresh water setting for one or more years, thus focusing on early stages of taphonomy. The considered taxa are species from Quercus (oak) and Fagus (beech). Deposited leaves from three fresh water environments in Southwestern Germany were studied: active stream in a forest, still water pond in a forest, and a waterlogged moor environment. Additionally to the isotope measurements, the degree of leaf tissue degradation and colonization with degrading organisms were observed with Scanning Electron Microscopy.

  9. Stable carbon isotope ratios and intrinsic water-use efficiency of Miocene fossil leaves compared to modern congeners

    Energy Technology Data Exchange (ETDEWEB)

    Marshall, J.D.; Zhang, J.; Rember, W.C.; Jennings, D.; Larson, P. (Univ. of Idaho, Moscow, ID (United States))

    1994-06-01

    Miocene fossil leaves of forest trees were extracted from the Clarkia, Idaho fossil beds and their stable carbon isotope ratios were analyzed. Fossils had higher lignin concentrations and lower cellulose concentrations that modern leaves due to diagenesis and the HF used to extract the fossils. Therefore, [delta][sup 13]C of extracted fossil lignin was compared to that of modern lignin. Fossil lignin [delta][sup 13]C was significantly different from that of congeneric modern leaves (paired t-test, P<0.0001), but was 1.9% less negative. Gymnosperms (Metasequoia, Taxodium) were less negative than angiosperms (e.g., Magnolia, Quercus, Acer, Persea), but no difference between evergreen and deciduous species was detected. Using published estimates of the concentration and [delta][sup 13]C of atmospheric CO[sub 2] during the Miocene was estimated the CO[sub 2] partial pressure gradient across the stomata (intrinsic water-use efficiency). Intrinsic water-use efficiency was at least 70% higher during this past [open quotes]greenhouse[close quotes] period than at present.

  10. Genetic diversity of Quercus glandulifera var. brevipetiolata populations in three forest communities with different succession stages

    Institute of Scientific and Technical Information of China (English)

    Junmin LI; Zexin JIN; Qiping GU; Wenyan LOU

    2009-01-01

    In order to understand the relationship between population succession and its genetic behavior, random amplified polymorphic DNA (RAPD) technique was used to analyze the genetic diversity of Quercu glandulifera var.brevipetiolata populations in three forest communities with different succession stages (coniferous forest, coniferous and broad-leaved mixed forest, evergreen broad-leaved forest). The results showed that 145 repetitive loci were produced in 60 individuals of Q. glandulifera using 11 primers, among which 120 loci were polymorphic, and the total percentage of polymorphic loci was 82.76% with an average of 64.14%. Estimated by the Shannon information index, the total genetic diversity of the three populations was 0.4747, with an average of 0.3642, while it was 0.3234, with an average of 0.2484, judged from the Nei index. Judged from percentage of polymorphic loci,Shannon inform at ion index and Nei index, the genetic diversity followed a decreasing order: coniferous forest >broad-leaved mixed forest > evergreen broad-leaved for-est. Analysis of molecular variance (AMOVA) showed that 69.73% of the genetic variance existed within populations and 30.27% of the genetic variance existed among popu-lations. The coefficient of gene differentiation (Gst) was 0.2319 and the gene flow (Nm) was 1.6539. The mean of genetic identity among populations of Q. glandulifera was 0.8501 and the mean of genetic distance was 0.1626. The genetic identity between the Q. glandulifera population in the coniferous forest and that in the coniferous and broad-leaved mixed forest was the highest. UPGMA cluster analysis based on Nei's genetic distance showed that the population in the coniferous forest gathered with that in the coniferous and broad-leaved mixed forest firstly, then with that in the evergreen broad-leaved forest. The genetic structure of Q. glandulifera was not only characteristic of the biological characteristics of this species, but was also influenced by the

  11. Geneti variation and selection among provenience of Quercus variabilis%栓皮栎不同种源苗期变异与初步选择

    Institute of Scientific and Technical Information of China (English)

    陈素传; 王陆军; 蔡新玲; 肖正东

    2012-01-01

    收集了栓皮栎分布区内25个种源种子,在肥西县花岗镇(蔡)冲村进行播种育苗试验,对其苗期生长性状、生物量进行测定分析.结果表明,栓皮栎苗高、地径生长均表现“S”形曲线,7-9月中旬为速生期;不同种源栓皮栎除根长存在显著差异外,苗高、地径、高径比、生物量均存在极显著差异;苗高与地径、茎、叶、总生物量呈极显著正相关,地径与根、茎、叶、总生物量也呈极显著正相关,根与茎、叶、总生物量同样呈极显著正相关.主成分分析表明,种源间的差异主要是由生物量和地径决定的.初步筛选出云南勐海、安徽东至、河南信阳、重庆酉阳、浙江杭州、安徽金寨2号、安徽绩溪7个优良种源.%25 provenience of Quercus variabilis seeds were collected from its main distribution area in China. Raising seedlings experiments were carried out at Caichong Village, Huanggang Town, Fein County, Anhui Province. Seedling growth trails and biniun-M were measured. The resuks showed that Q. imriabilis seedling height and ground diameter growth showed an "S" curve, with July to September as the fast-growing period. Sagnifrcani differences were observed on height, ground diameter, heighl to diameter ratio, biomass and roots from different Q. vanobilis provenience, Height was significantly positive related >o ground diameter, stems, leaves, total biomass. Significant positive correlation was also observed between ground diameter and root, stem, leaves, the total biomass. Similarly, roots were significantly positive correlated with the s!玬, leaves, bioma&s loo- Phitttpal component analysis showed that the main differences among pcoveaience were decided by the ground diameter and biomass of vanous parts of the plant. Seven improved provenience. originated from Menghai of Yunan Province, Dongzhi of Aohui Province. Xingvane of Henan Province. Youyang of Chongqin city, Hangzhou of Zhe-jiang Province, No. 2

  12. Study on Aboveground Biomass Model of Natural Individual Trees of Quercus acutissima%天然麻栎单木地上生物量模型研究

    Institute of Scientific and Technical Information of China (English)

    许剑辉; 汪茂林; 黄庆丰; 宫守飞

    2011-01-01

    Based on an investigation of aboveground biomasses of sample trees of Quercus acutissima in Yeshan Forest Farm of Tongling County,the relative growth style,power function and polynomial were selected to be the biomass regression models,with DBH and tree height as independent variables,and total aboveground biomass and biomasses of the tree trunks,branches and leaves as the dependent variables.The model parameters and correlative indexes,regression residual errors were fitted and biomass estimation errors were calculated.The results showed that there is significant power function relation between the biomasses of trunks,branches and leaves,and total aboveground part of the trees and their DBH and height.The equations are:Tree trunk biomass W=6.571×10-4D1.8473H2.411;Biomass of branches W=1.163×10-4D2.9497H1.3223;Biomass of leaves W=0.0032D1.5148H0.8821;Total aboveground biomass W=9.354×10-4D2.0825H2.1154.The precisions of the estimated trunk and total biomasses were more than 90%.%通过对铜陵叶山林场麻栎样木地上生物量调查,以胸径、树高为自变量,地上总生物量、树干、树枝、树叶生物量为因变量,选择相对生长式、幂函数式和多项式为生物量回归模型,拟合各模型参数、相关指数、回归剩余离差,并计算生物量估测误差。结果表明:麻栎树干、树枝、树叶和地上总生物量与胸径、树高存在显著幂函数关系,其方程分别为:树干W=6.571×10-4D1.8473H2.411、树枝W=1.163×10-4D2.9497H1.3223、树叶W=0.0032D1.5148H0.8821、总生物量W=9.354×10-4D2.0825H2.1154。树干与总生物量的预估精度均达90%以上。

  13. Direct-seeding of commercial trees on surface-mine spoil. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Graves, D.H.; Carpenter, S.B.; Wittwer, R.F.

    1980-04-01

    Two small-seeded species, Paulownia (Paulownia tomentosa), and European alder (Alnus glutinosa) and three large seeded species, northern red oak (Quercus rubra), pin oak (Quercus palustris), and bur oak (Quercus macrocarpa) were direct-seeded on three aspects on minesoil in eastern Kentucky. Treatments included four mulch applications--water-borne fiber mulch, hardwood bark, bark and manure, and composted municipal waste; and two fertilizer applications. Growth and survival were evaluated during two consecutive growing seasons.

  14. Efeito da pastorícia tradicional na redução de combustíveis em bosques de Quercus pyrenaica

    OpenAIRE

    Castro, Marina; Castro, José; Gómez Sal, Antonio

    2005-01-01

    Os bosques de Quercus pyrenaica foram no passado e continuam no presente, a ser utilizados por rebanhos de pequenos ruminantes (ovelhas e cabras) explorados em regime extensivo, pelo que são frequentemente considerados sistemas de uso múltiplo. Neste trabalho investiga-se o efeito da pastorícia tradicional na redução da acumulação de biomassa herbácea, pretendendo avaliar o efeito da presença dos animais nestes sistemas. Avaliou-se a biomassa herbácea em bosques de Quercus pyrenaica em doi...

  15. Establecimiento de cuatro especies de Quercus en el sur de la Península Ibérica: factores condicionantes

    OpenAIRE

    2010-01-01

    Las especies del género Quercus son muy representativas del estrato arbóreo de los bosques mediterráneos y presentan limitaciones para su regeneración, siendo la fase de plántula muy sensible a las condiciones ambientales (Jordano et al. 2008). En esta tesis se han estudiado algunos de los factores clave para el establecimiento de varias especies de Quercus (Q. ilex ssp ballota, Q. suber, Q. faginea, Q. pyrenaica), abarcando las fases de depredación post-dispersiva, emergencia, crecimiento y ...

  16. Independencia y ecología ectomicorrícica en varias especies de los géneros Quercus, Pinus y Eucalyptus

    OpenAIRE

    Oria de Rueda Salguero, Juan Andrés

    1991-01-01

    Se estudia la micorrización de varias especies de Quercus y Eucalyptus con hongos micorrícicos de los géneros Pisolithus, Krombholziella y Suillus. Se define el Período de Independencia Micorrícica, muy interesante en viveros forestales y de reproducción vegetal.Este período varía según especies y ecología y es mayor con semillas voluminosas que en las de semillas pequeñas. Mycorrization of some species of Quercus, Pinus and Eucalyptus with some mycorrhizal fungi: Pisolithus,Krombholziella...

  17. Ecología, historia y gestión de los árboles del género Quercus: simposio de Isparta, Turquía

    OpenAIRE

    Marañón, T.

    2011-01-01

    El género Quercus tiene más de 400 especies repartidas por el Hemisferio Norte. Los robles, encinas, alcornoques, quejigos y coscojas forman parte del paisaje europeo y mediterráneo y tienen un importante valor ecológico, económico y cultural. En junio de 2010 tuvo lugar en Isparta (Turquía) el segundo simposio europeo sobre la importancia de los árboles del género Quercus, 'su contribución pasada, presente y futura al paisaje, la biodiversidad, el patrimonio y el turismo europeo' (v...

  18. Age-related variation in carbon allocation at tree and stand scales in beech (Fagus sylvatica L.) and sessile oak (Quercus petraea (Matt.) Liebl.) using a chronosequence approach.

    Science.gov (United States)

    Genet, H; Bréda, N; Dufrêne, E

    2010-02-01

    Two types of physiological mechanisms can contribute to growth decline with age: (i) the mechanisms leading to the reduction of carbon assimilation (input) and (ii) those leading to modification of the resource economy. Surprisingly, the processes relating to carbon allocation have been little investigated as compared to research on the processes governing carbon assimilation. The objective of this paper was thus to test the hypothesis that growth decrease related to age is accompanied by changes in carbon allocation to the benefit of storage and reproductive functions in two contrasting broad-leaved species: beech (Fagus sylvatica L.) and sessile oak (Quercus petraea (Matt.) Liebl.). Age-related changes in carbon allocation were studied using a chronosequence approach. Chronosequences, each consisting of several even-aged stands ranging from 14 to 175 years old for beech and from 30 to 134 years old for sessile oak, were divided into five or six age classes. In this study, carbon allocations to growth, storage and reproduction were defined as the relative amount of carbon invested in biomass increment, carbohydrate increment and seed production, respectively. Tree-ring width and allometric relationships were used to assess biomass increment at the tree and stand scales. Below-ground biomass was assessed using a specific allometric relationship between root:shoot ratio and age, established from the literature review. Seasonal variations of carbohydrate concentrations were used to assess carbon allocation to storage. Reproduction effort was quantified for beech stands by collecting seed and cupule production. Age-related flagging of biomass productivity was assessed at the tree and stand scales, and carbohydrate quantities in trees increased with age for both species. Seed and cupule production increased with stand age in beech from 56 gC m(-)(2) year(-1) at 30 years old to 129 gC m(-2) year(-1) at 138 years old. In beech, carbon allocation to storage and

  19. Leaving the hospital - your discharge plan

    Science.gov (United States)

    ... medlineplus.gov/ency/patientinstructions/000867.htm Leaving the hospital - your discharge plan To use the sharing features ... please enable JavaScript. After an illness, leaving the hospital is your next step toward recovery. Depending on ...

  20. Smoking Leaves Lasting Marks on DNA: Study

    Science.gov (United States)

    ... fullstory_161060.html Smoking Leaves Lasting Marks on DNA: Study Changes related to disease found in more ... cigarettes can leave a lasting imprint on human DNA, altering more than 7,000 genes in ways ...

  1. Pre-exposure to ozone predisposes oak leaves to attacks by Diplodia corticola and Biscogniauxia mediterranea.

    Science.gov (United States)

    Paoletti, Elena; Anselmi, Naldo; Franceschini, Antonio

    2007-01-01

    One-year-old cork oak (Quercus suber) and turkey oak (Q. cerris) seedlings were exposed to ozone (110 ppb, 5 h day(-1), for 30 days) and were inoculated with Diplodia corticola and Biscogniauxia mediterranea, respectively, by spraying a suspension of spores on the leaves. Both fungi are endophytic and may act as weak parasites, contributing to oak decline. Ozone exposure stimulated leaf attacks after inoculation, although the physiological, visible, and structural responses of both oaks to O3 exposure were weak. In fact, steady-state gas exchange, leaf waxes, and wettability were not significantly affected by O3. In Q. cerris, O3 altered the structure of stomata, as observed by scanning microscopy, and reduced the leaf relative water content. No hyphal entry through stomata or growth towards stomata was, however, observed. Inoculations were performed in a humid chamber at low light; stomata were likely to be closed. When Q. cerris was inoculated in natural conditions, i.e., in a forest infected by B. mediterranea, seedlings pre-exposed to the enhanced O3 regime had a higher number of B. mediterranea isolates than the controls. This suggests that pre-exposure to O3 predisposed Q. cerris leaves to attacks by B. mediterranea independent of stomata. The hyphae of both fungi were able to enter the leaf through the cuticle, either by gradual in-growth into the cuticle or erosion of a hollow in the cuticle at the point of contact. The primary cause of increased leaf injury in O3-exposed seedlings appeared to be higher germination of spores than on control leaves.

  2. Pre-Exposure to Ozone Predisposes Oak Leaves to Attacks by Diplodia corticola and Biscogniauxia mediterranea

    Directory of Open Access Journals (Sweden)

    Elena Paoletti

    2007-01-01

    Full Text Available One-year-old cork oak (Quercus suber and turkey oak (Q. cerris seedlings were exposed to ozone (110 ppb, 5 h day˗1, for 30 days and were inoculated with Diplodia corticola and Biscogniauxia mediterranea, respectively, by spraying a suspension of spores on the leaves. Both fungi are endophytic and may act as weak parasites, contributing to oak decline. Ozone exposure stimulated leaf attacks after inoculation, although the physiological, visible, and structural responses of both oaks to O3 exposure were weak. In fact, steady-state gas exchange, leaf waxes, and wettability were not significantly affected by O3. In Q. cerris, O3 altered the structure of stomata, as observed by scanning microscopy, and reduced the leaf relative water content. No hyphal entry through stomata or growth towards stomata was, however, observed. Inoculations were performed in a humid chamber at low light; stomata were likely to be closed. When Q. cerris was inoculated in natural conditions, i.e., in a forest infected by B. mediterranea, seedlings pre-exposed to the enhanced O3 regime had a higher number of B. mediterranea isolates than the controls. This suggests that pre-exposure to O3 predisposed Q. cerris leaves to attacks by B. mediterranea independent of stomata. The hyphae of both fungi were able to enter the leaf through the cuticle, either by gradual in-growth into the cuticle or erosion of a hollow in the cuticle at the point of contact. The primary cause of increased leaf injury in O3-exposed seedlings appeared to be higher germination of spores than on control leaves.

  3. Conservation and fruit biology of Sichou oak (Quercus sichourensis, Fagaceae – A critically endangered species in China

    Directory of Open Access Journals (Sweden)

    Ke Xia

    2016-10-01

    Full Text Available Several conservation programs have been started for the critically endangered Sichou oak (Quercus sichourensis since 2007. These programs include detailed field investigations, seedling cultivation and research on the fruit biology of the species. In this study, we first report on the five mature individual trees found in our 9-year field investigation. Thus far, a total of 10 mature individuals have been recorded. All Q. sichourensis trees are healthy and most produce healthy acorns. Acorns of Q. sichourensis are large with dry masses of 8.0–14.0 g. These acorns had high moisture contents at collection and died shortly after (7–28 d when dried with silica gel. Characteristics of Q. sichourensis acorns varied between populations. Compared with the acorns from Funing, the acorns collected from Ceheng were bigger, more viable (germination percentage was up to 96%, less sensitive to desiccation, and germinated faster. Q. sichourensis occurs in regions with a distinct 5–6 month dry season. Habitat degradation is largely responsible for the rareness of Quercus sichorensis, but desiccation sensitivity of the acorns may also limit the regeneration of the species and potentially lead to its continued rareness. As a species with extremely small populations (PSESP, Q. sichourensis is facing high risk of extinction and should be defined as a Critically Endangered species in the global IUCN Red List.

  4. Tree-ring growth and wood chemistry response to manipulated precipitation variation for two temperate Quercus species

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, Rebekah J. [Pennsylvania State University, University Park, PA; Kaye, Margot W. [Pennsylvania State University, University Park, PA; Abrams, Marc D. [Pennsylvania State University, University Park, PA; Hanson, Paul J [ORNL; Martin, Madhavi Z [ORNL

    2012-01-01

    We examined the relationship among ambient and manipulated precipitation, wood chemistry, and their relationship with radial growth for two oak species in eastern Tennessee. The study took place on the Walker Branch Throughfall Displacement Experiment (TDE) site, located at the Oak Ridge National Laboratory in Oak Ridge, TN. Two dominant species, white oak (Quercus alba) and chestnut oak (Quercus prinus), were selected for study from a 13-year experiment of whole-stand precipitation manipulation (wet, ambient and dry). The relationships between tree-ring width and climate were compared for both species to determine the impact of precipitation manipulations on ring width index. This study used experimental spectroscopy techniques to measure the sensitivity of tree-ring responses to directional changes in precipitation over 13 years, and the results suggest that oaks at this study site are resilient to imposed changes, but sensitive to inter-annual variations in climate. Laser-induced breakdown spectroscopy (LIBS) allowed us to measure nutrient intensities (similar to element concentrations) at 0.5-1.0 mm spacing along the radial growth axis of trees growing in the wet, ambient, and dry treatment sites. A difference in stemwood nutrient levels was observed between the two oak species and among the three treatments. Significant variation in element intensity was observed across treatments for some elements (Ca, K, Mg, Na, N and P) suggesting the potential for long-term impacts on growth under a changing climate regimes for southeastern oaks.

  5. [Effects of relative abundance of Quercus mongolica acorns on five tree species seed dispersal in Xiaoxing' an Mountains, Northeast China].

    Science.gov (United States)

    Yu, Fei; Shi, Xiao-Xiao; Yi, Xian-Feng; Wang, De-Xiang

    2013-06-01

    An investigation was conducted in a forest farm in the Xiaoxing' an Mountains in autumn, 2009 and 2010 to study the effects of Quercus mongolica acorn quantity and rodent density on the seed dispersal of five tree species (Juglans mandshurica, Pinus koraiensis, Corylus mandshurica, Corylus heterophylla, and Q. mongolica). In the farm, there was an annual change in rodent density. The total capture rate of small rodents in 2009 (31.0%) was significantly higher than that in 2010 (16.7%). The acorn quantity and relative seed abundance (per capita rodent) of Quercus mongolica in 2009 (6.2 +/- 2.1 acorns x m(-2) and 20.0, respectively) were significantly lower than those in 2010 (26.7 +/- 10.2 acorns x m(-2) and 160.0, respectively). In 2009, all the seeds of the five tree species except J. mandshurica were dispersed or eaten in situ, among which, the acorns of Q. mongolica were scatter-hoarded most, and their average dispersal distance was the furthest. In 2010, the seeds of J. mandshurica were scatter-hoarded most, and their average dispersal distance was the furthest. The relative seed abundance of Q. mongolica could be the key factor determining the seed dispersal of the other tree species in the study area.

  6. Biomass dynamics of Quercus aliena var.acutesrata Community on Mountain Xiaolong in Gansu Province,China

    Institute of Scientific and Technical Information of China (English)

    Suo Anning; Ju Tianzhen; Zhang Junhua; Ge Jianping

    2006-01-01

    The dynamics of tree layer biomass was studied by combining 35 sample plots of field census with biomass model estimation in a natural Quercus aliena var.acutesrata community on Mountain Xiaolong in Gansu Province,China.The tree layer biomass of Quercus aliena var.acutesrata community was 183 660 kg/ha,in which the slow growth group accounted for 64.89% of the total biomass.The fast-medium growth group accounted for 33.40% and the coniferous group accounted for 1.38%.The organs biomass was found to be in the following order:trunk>root>branch>leaf.The total biomass accumulated with the development of the community.The total biomass and the biomass of the organs were highest in the mature community and became stable as the community developed.The relative growth rate of organs was in the following order:trunk>branch>root>leaf.The biomass ratio of the slow growth group trees tended to increase and the fast-medium group trees tended to decrease as the community developed,which was reveresed in the decline development stage.The biomass of the coniferous group was very small throughout the development process.

  7. Evaluation of Analgesic Activity of the Methanol Extract from the Galls of Quercus infectoria (Olivier in Rats

    Directory of Open Access Journals (Sweden)

    Sook-Ha Fan

    2014-01-01

    Full Text Available The present study aims to investigate the analgesic activity of the methanol extract of the galls of Quercus infectoria in rats using hot plate and tail-flick methods. The extract was administered intraperitoneally at a dose of 20 mg/kg while morphine sulfate and sodium salicylate (10 mg/kg served as standards. The methanol extract exhibited significant analgesic activity in the tail-flick model (P<0.05 by increasing the reaction time of the rats to 8.0 sec at 30 min after treatment in comparison to control (4.4 sec. Morphine sulfate produced a reaction time of 11.9 sec in the same test. At the peak of activity (30 min, the extract produced maximum possible analgesia (MPA of 34.2%, whilst morphine sulfate achieved a peak MPA of 70.9%. No analgesic effects have been observed using sodium salicylate in the tail-flick model. In the same model, the extract and sodium salicylate demonstrated comparable reaction times. Tail-flick is a better method to evaluate analgesic activity as no significant results were observed for all treatments using hot plate with the exception of morphine sulfate, which showed significant results only at 45 and 60 min after treatment. In conclusion, the methanol extract of the galls of Quercus infectoria displayed analgesic activity.

  8. Frequent cytoplasmic exchanges between oak species that are not closely related: Quercus suber and Q. ilex in Morocco.

    Science.gov (United States)

    Belahbib, N; Pemonge, M H; Ouassou, A; Sbay, H; Kremer, A; Petit, R J

    2001-08-01

    Chloroplast (cp) and mitochondrial (mt) DNA variation were studied in 97 populations of cork oak (Quercus suber) in Morocco; in 31 of these populations, holm oak (Quercus ilex), a clearly distinct species, also occurred and was compared with Q. suber. Three cpDNA and one mtDNA primer pairs were used in the survey, each in combination with one restriction enzyme. Six haplotypes belonging to two very divergent lineages were detected; one lineage predominates in each species, and is probably ancestral, as inferred from comparisons with other oak species. In the mixed-species populations, cytoplasmic genomes were frequently shared across species, as indicated by an introgression ratio of 0.63. This index is a new measure of the propensity of species to share locally genetic markers, varying from zero (complete differentiation) to one (no differentiation). By contrast, more closely related deciduous oak species (Q. robur, Q. petraea and Q. pubescens) have introgression ratios varying from 0.82 to 0.97. The introgression events appear to have been more frequent in the direction Q. ilex (female) x Q. suber (male), a finding which seems attributable to the flowering phenology of these two species. This asymmetry may have favoured immigration of Q. suber beyond its main range, in regions already colonized by Q. ilex. There, rare hybridization and further introgression through long distance pollen flow have established populations that are morphologically indistinguishable from Q. suber but that have cytoplasmic genomes originating from the local Q. ilex populations.

  9. Proteomic analysis from haploid and diploid embryos of Quercus suber L. identifies qualitative and quantitative differential expression patterns.

    Science.gov (United States)

    Gómez, Aranzazu; López, Juan Antonio; Pintos, Beatriz; Camafeita, Emilio; Bueno, Ma Angeles

    2009-09-01

    Quercus suber L. is a Mediterranean forest species with ecological, social and economic value. Clonal propagation of Q. suber elite trees has been successfully obtained from in vitro-derived somatic and gametic embryos. These clonal lines play a main role in breeding and genetic studies of Q. suber. To aid in unravelling diverse genetic and biological unknowns, a proteomic approach is proposed. The proteomic analysis of Q. suber somatic and gametic in vitro culture-derived embryos, based on DIGE and MALDI-MS, has produced for the first time proteomic data on this species. Seventeen differentially expressed proteins have been identified which display significantly altered levels between gametic and somatic embryos. These proteins are involved in a variety of cellular processes, most of which had been neither previously associated with embryo development nor identified in the genus Quercus. Some of these proteins are involved in stress and pollen development and others play a role in the metabolism of tannins and phenylpropanoids, which represent two of the major pathways for the synthesis of cork chemical components. Furthermore, the augmented expression levels found for specific proteins are probably related to the homozygous state of a doubled-haploid sample. Proteins involved in synthesis of cork components can be detected at such early stages of development, showing the potential of the method to be useful in searching for biomarkers related to cork quality.

  10. Drought impact on Quercus pubescens Willd. isoprene emissions over the Mediterranean area: what future?

    Science.gov (United States)

    Cyrielle Genard-Zielinski, Anne; Boissard, Christophe; Ormeño, Elena; Lathière, Juliette; Guenet, Bertrand; Gauquelin, Thierry; Fernandez, Catherine

    2015-04-01

    Biogenic Volatile Organic Compounds (BVOCs) released by plants mostly originate from their secondary metabolism. Their emissions are modulated, in terms of intensity and molecule diversity, by environmental conditions. Among BVOCs, isoprene has been especially studied due to its high emission fluxes and its contribution to tropospheric photochemistry, both in the gaseous and particulate phases. However, the way isoprene emissions are impacted by some abiotic factors, especially water stress, is still under debate. In a world facing climatic changes, global climate models expect air temperature and drought intensity to strengthen in the Mediterranean area by 2100. Our work focuses on the impact of water stress on isoprene emissions (ERiso) from Quercus pubescens Willd. This species covers large areas of the Mediterranean area where it appears to be the main isoprene emitter. An in situ experimentation was performed at the O3HP (Oak Observatory at OHP, southern France) in a pubescent oak forest with trees adapted to long lasting stress periods. We investigated during a whole seasonal cycle (from June 2012 to June 2013) the course of ERiso under both natural water stress (control treatment: C) and intensified water stress (stress treatment: S) by artificially reducing rain by 30% using a specific rain exclusion device. Restricted rain did not modify either the net CO2 assimilation or ERiso during the whole season. However, isoprene emission factors (Is) for trees under S were significantly higher (a factor of ˜ 2) than for trees growing under C in August (137.8 compared to 75.3 μgC.gDM-1.h-1 respectively) and September (75.3 compared to 40.2 μgC.gDM-1.h-1 respectively). Based on our experimental emission database, an appropriate isoprene emission algorithm (GZ2014) was developed using a statistic approach (an artificial neural network). Using ambient and edaphic environmental parameters integrated over up to 3 weeks, GZ2014 was found to represent more than 80% of

  11. Species-specific climate response of oaks (Quercus spp. under identical environmental conditions

    Directory of Open Access Journals (Sweden)

    Sanders TGM

    2014-04-01

    Full Text Available Oak forests play a major role in Britain due to their economic, social and historic value. Sudden oak death and general decline symptoms have therefore caused major concerns in the forestry sector over the past decade. Several strategies have been proposed to preserve the economic and social value of oak forests, including the planting of native species with more southerly origins, or non-native species of oak that may be better suited to the projected climate of the future. The Ovington research plots, established 50 years ago at the Bedgebury Pinetum in southeast England, provided the opportunity to compare annual growth rates and climate-growth relationships of five oak species growing adjacent to each other on the same soil type and under the same climatic conditions. Clear differences were evident in annual increment and climate-growth responses for the five Quercus species. Growth rates were significantly lower (p<0.05 for the two species native to the UK (Q. petraea and Q. robur compared to the southern European and American species. A partitioning analysis using key climatic variables separates Q. coccinea from the other species due to its negative response to low temperatures. These results were confirmed by pointer year analysis. The analysis suggests that Q. robur is likely to be the more resilient of the two native species of oak to the future climate of southern Britain. Of the non-native species of oak evaluated, Q. coccinea represents an alternative species to Q. robur and Q. petraea on very dry, nutrient-poor sites. Q. palustris may also have some potential under current conditions for species diversification, but its requirement for higher summer precipitation than the other four species suggests that this potential may not be sustained as climate change progresses. However, if alternative species are selected as more resilient to climate change in terms of growth, it will be essential to consider a range of other issues

  12. Quercus robur vitality structure and its dynamics at the initial stages of ontogeny

    Directory of Open Access Journals (Sweden)

    V. M. Dehtiarov

    2015-07-01

    Full Text Available We present the results of evaluation of vitality structure of ontogenetic subcenopopulations of juvenile and immature (im1 and im2 plants Quercus robur L. in seven aggregations of forest vegetation of Krolevets-Hlukhiv Geobotanical Region. It is found that ontogenetic subcenopopulations of Q. robur young generation, formed under canopy of deciduous forests of the region under study, are noted for high level of vitality structure diversity and for having three qualitative types: blooming, balanced and depressive ones. It is observed that dynamics of Q quality index values in ontogenetic subcenopopulations Q. robur in the aggregations under study fits three variants of changes. In the first one we can see stable decrease of Q quality index values in the line j → im1 → im2. Three of seven aggregations under study have dynamics of Q index values fitting the variant where increase of values takes place in the phase j → im1, and their decrease occurs in the phase im1 → im2. Q index values also decrease in the phase j → im1 and their increase in the phase im1 → im2 is established in three more phytocenoces. It is proved that change to every next phase of development (from j to im1, and also from im1 to im2 is accompanied by the appearance of vitality plasticity in Q. robur young generation (i.e. Q quality index value changes and vitality variability (changes of share of individuals of various vitality classes, respectively. Quantitative as well as qualitative aspects of vitality plasticity realization are evaluated based on the original factor – index of vitality dynamics – IVD. It is found that at the initial stages of ontogenetic development negative changes of vitality structure in Q. robur happen more often then positive ones. Decrease in the individuals’ vitality and worsening of vitality structure are mainly accompanied by the reduction of cohort quality status. Ascertained facts as for vitality structure of ontogenetic

  13. Whole-transcriptome response to water stress in a California endemic oak, Quercus lobata.

    Science.gov (United States)

    Gugger, Paul F; Peñaloza-Ramírez, Juan Manuel; Wright, Jessica W; Sork, Victoria L

    2016-12-21

    Reduced water availability during drought can create major stress for many plant species. Within a species, populations with a history of seasonal drought may have evolved the ability to tolerate drought more than those in areas of high precipitation and low seasonality. In this study, we assessed response to water stress in a California oak species, Quercus lobata Née, by measuring changes in gene expression profiles before and after a simulated drought stress treatment through water deprivation of seedlings in a greenhouse setting. Using whole-transcriptome sequencing from nine samples from three collection localities, we identified which genes are involved in response to drought stress and tested the hypothesis that seedlings sampled from climatically different regions of the species range respond to water stress differently. We observed a surprisingly massive transcriptional response to drought: 35,347 of 68,434 contigs (52%) were differentially expressed before versus after drought treatment, of which 18,111 were down-regulated and 17,236 were up-regulated. Genes functionally associated with abiotic stresses and death were enriched among the up-regulated genes, whereas metabolic and cell part-related genes were enriched among the down-regulated. We found 56 contigs that exhibited significantly different expression responses to the drought treatment among the three populations (treatment × population interaction), suggesting that those genes may be involved in local adaptation to drought stress. These genes have stress response (e.g., WRKY DNA-binding protein 51 and HSP20-like chaperones superfamily protein), metabolic (e.g., phosphoglycerate kinase and protein kinase superfamily protein), transport/transfer (e.g., cationic amino acid transporter 7 and K(+) transporter) and regulatory functions (e.g., WRKY51 and Homeodomain-like transcriptional regulator). Baseline expression levels of 1310 unique contigs also differed among pairs of populations, and they

  14. Sugar beet leaves for functional ingredients

    NARCIS (Netherlands)

    Tamayo Tenorio, Angelica

    2017-01-01

    Plant leaves are recognised as a potential source for food applications based on their nutritional profile and interesting technological properties of leaf components, and based on the large availability of plant leaves in agricultural waste streams. Besides proteins, leaves have a rich nutritional

  15. Compassionate Care Leave & Benefits. CAUT Briefing Note

    Science.gov (United States)

    Canadian Association of University Teachers, 2016

    2016-01-01

    Compassionate care leave and benefits were introduced in 2003/04 to help employees cope with this difficult work-life balance challenge. Employment Standards legislation and the Employment Insurance program (EI) were amended to provide leave without pay, with payment of EI benefits for compassionate care leave. Collective agreements have been…

  16. Resource capture by single leaves

    Energy Technology Data Exchange (ETDEWEB)

    Long, S.P.

    1992-05-01

    Leaves show a variety of strategies for maximizing CO{sub 2} and light capture. These are more meaningfully explained if they are considered in the context of maximizing capture relative to the utilization of water, nutrients and carbohydrates reserves. There is considerable variation between crops in their efficiency of CO{sub 2} and light capture at the leaf level. Understanding of these mechanisms indicate some ways in which efficiency of resource capture could be level cannot be meaningfully considered without simultaneous understanding of implications at the canopy level. 36 refs., 5 figs., 1 tab.

  17. 5 CFR 630.1015 - Movement between voluntary leave bank and leave transfer programs.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Movement between voluntary leave bank and leave transfer programs. 630.1015 Section 630.1015 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS ABSENCE AND LEAVE Voluntary Leave Bank Program § 630.1015...

  18. 5 CFR 630.1104 - Donations from a leave bank to an emergency leave transfer program.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Donations from a leave bank to an emergency leave transfer program. 630.1104 Section 630.1104 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS ABSENCE AND LEAVE Emergency Leave Transfer Program § 630.1104...

  19. 5 CFR 630.1013 - Participation in voluntary leave transfer and leave bank programs.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Participation in voluntary leave transfer and leave bank programs. 630.1013 Section 630.1013 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS ABSENCE AND LEAVE Voluntary Leave Bank Program § 630.1013...

  20. 5 CFR 630.1009 - Use of annual leave withdrawn from a leave bank.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Use of annual leave withdrawn from a leave bank. 630.1009 Section 630.1009 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS ABSENCE AND LEAVE Voluntary Leave Bank Program § 630.1009 Use of annual...

  1. 5 CFR 630.1004 - Application to become a leave contributor and leave bank member.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Application to become a leave contributor and leave bank member. 630.1004 Section 630.1004 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS ABSENCE AND LEAVE Voluntary Leave Bank Program § 630.1004 Application...

  2. Effects of drought and shade on growth and water use of Quercus alba, Q. bicolor, Q. imbricaria and Q. palustris seedlings

    Science.gov (United States)

    Joseph J. McCarthy; Jeffrey O. Dawson

    1991-01-01

    Growth and water use efficiency were determined for 2-year-old white oak (Quercus alba), swamp white oak (Q. imbricaria) and pin oak (Q. palustris) seedlings grown under three shade treatments (30, 55 and 73%) and two irrigation regimes (container capacity and mild drought). With species and water regimes...

  3. Experimental drought reduced acid and alkaline phosphatase activity and increased organic extractable P in soil in a Quercus ilex Mediterranean forest

    NARCIS (Netherlands)

    Sardans, J.; Penuelas, J.; Ogaya, R.

    2008-01-01

    A six-year (1999-2005) experiment of drought manipulation was conducted in a Quercus ilex Mediterranean forest (Southern Catalonia) to simulate predicted climatic conditions projected for the decades to come. The aim was to investigate the direct and indirect effects of drought conditions on acid an

  4. Respuesta plástica a la luz y al agua en cuatro especies mediterráneas del género Quercus (Fagaceae)

    NARCIS (Netherlands)

    Quero Perez, J.L.; Villar, R.; Marañón, T.; Murillo, A.; Zamora, R.

    2008-01-01

    Light and water availability are two of the main factors that regulate growth and survival of Mediterranean woody plants. The objective of this study is to investigate the plastic response of seedlings of four Mediterranean Quercus species to these factors, as well as to determine what traits are

  5. Influence of overstory density on ecophysiology of red oak (Quercus rubra) and sugar maple (Acer saccharum) seedlings in central Ontario shelterwoods

    Science.gov (United States)

    William C. Parker; Daniel C. Dey

    2008-01-01

    A field experiment was established in a secondgrowth hardwood forest dominated by red oak (Quercus rubra L.) to examine the effects of shelterwood overstory density on leaf gas exchange and seedling water status of planted red oak, naturally regenerated red oak and sugar maple (Acer saccharum Marsh.) seedlings during the first...

  6. Respuesta plástica a la luz y al agua en cuatro especies mediterráneas del género Quercus (Fagaceae)

    NARCIS (Netherlands)

    Quero Perez, J.L.; Villar, R.; Marañón, T.; Murillo, A.; Zamora, R.

    2008-01-01

    Light and water availability are two of the main factors that regulate growth and survival of Mediterranean woody plants. The objective of this study is to investigate the plastic response of seedlings of four Mediterranean Quercus species to these factors, as well as to determine what traits are mo

  7. Broad Leaves in Strong Flow

    CERN Document Server

    Miller, Laura

    2013-01-01

    Flexible broad leaves are thought to reconfigure in the wind and water to reduce the drag forces that act upon them. Simple mathematical models of a flexible beam immersed in a two-dimensional flow will also exhibit this behavior. What is less understood is how the mechanical properties of a leaf in a three-dimensional flow will passively allow roll up into a cone shape and reduce both drag and vortex induced oscillations. In this fluid dynamics video, the flows around the leaves are compared with those of simplified sheets using 3D numerical simulations and physical models. For some reconfiguration shapes, large forces and oscillations due to strong vortex shedding are produced. In the actual leaf, a stable recirculation zone is formed within the wake of the reconfigured cone. In physical and numerical models that reconfigure into cones, a similar recirculation zone is observed with both rigid and flexible tethers. These results suggest that the three-dimensional cone structure in addition to flexibility is ...

  8. Phytic acid in green leaves.

    Science.gov (United States)

    Hadi Alkarawi, H; Zotz, G

    2014-07-01

    Phytic acid or phytate, the free-acid form of myo-inositolhexakiphosphate, is abundant in many seeds and fruits, where it represents the major storage form of phosphorus. Although also known from other plant tissues, available reports on the occurrence of phytic acid, e.g. in leaves, have never been compiled, nor have they been critically reviewed. We found 45 published studies with information on phytic acid content in leaves. Phytic acid was almost always detected when studies specifically tried to detect it, and accounted for up to 98% of total P. However, we argue that such extreme values, which rival findings from storage organs, are dubious and probably result from measurement errors. Excluding these high values from further quantitative analysis, foliar phytic acid-P averaged 2.3 mg·g(-1) , and represented, on average, 7.6% of total P. Remarkably, the ratio of phytic acid-P to total P did not increase with total P, we even detected a negative correlation of the two variables within one species, Manihot esculenta. This enigmatic finding warrants further attention.

  9. A comparison of fungal endophytic community diversity in tree leaves of rural and urban temperate forests of Kanto district, eastern Japan.

    Science.gov (United States)

    Matsumura, Emi; Fukuda, Kenji

    2013-03-01

    To clarify the effects of forest fragmentation and a change in tree species composition following urbanization on endophytic fungal communities, we isolated fungal endophytes from the foliage of nine tree species in suburban (Kashiwa City, Chiba) and rural (Mt. Wagakuni, Ibaraki; Mt. Takao, Tokyo) forests and compared the fungal communities between sites and host tree species. Host specificity was evaluated using the index of host specificity (Si), and the number of isolated species, total isolation frequency, and the diversity index were calculated. From just one to several host-specific species were recognized in all host tree species at all sites. The total isolation frequency of all fungal species on Quercus myrsinaefolia, Quercus serrata, and Chamaecyparis obtusa and the total isolation frequency of host-specific species on Q. myrsinaefolia, Q. serrata, and Eurya japonica were significantly lower in Kashiwa than in the rural forests. The similarity indices (nonmetric multidimensional scaling (NMS) and CMH) of endophytic communities among different tree species were higher in Kashiwa, as many tree species shared the same fungal species in the suburban forest. Endophytic fungi with a broad host range were grouped into four clusters suggesting their preference for conifer/broadleaves and evergreen/deciduous trees. Forest fragmentation and isolation by urbanization have been shown to cause the decline of host-specific fungal species and a decrease in β diversity of endophytic communities, i.e., endophytic communities associated with tree leaves in suburban forests were found to be depauperate.

  10. Quantitative RT-PCR analysis of differentially expressed genes in Quercus suber in response to Phytophthora cinnamomi infection.

    Science.gov (United States)

    Ebadzad, Ghazal; Cravador, Alfredo

    2014-01-01

    cDNA-AFLP methodology was used to gain insight into gene fragments differentially present in the mRNA profiles of Quercus suber roots infected with zoospores of Phytophthora cinnamomi at different post challenge time points. Fifty-three transcript-derived fragments (TDFs) were identified and sequenced. Six candidate genes were selected based on their expression patterns and homology to genes known to play a role in defence. They encode a cinnamyl alcohol dehydrogenase2 (QsCAD2), a protein disulphide isomerase (QsPDI), a CC-NBS-LRR resistance protein (QsRPc), a thaumatin-like protein (QsTLP), a chitinase (QsCHI) and a 1,3-β-glucanase (QsGlu). Evaluation of the expression of these genes by quantitative polymerase chain reaction (qPCR) revealed that transcript levels of QsRPc, QsCHI, QsCAD2 and QsPDI increased during the first 24 h post-inoculation, while those of thaumatin-like protein decreased. No differential expression was observed for 1,3-β-glucanase (QsGlu). Four candidate reference genes, polymerase II (QsRPII), eukaryotic translation initiation factor 5A (QsEIF-5A), β-tubulin (QsTUB) and a medium subunit family protein of clathrin adaptor complexes (QsCACs) were assessed to determine the most stable internal references for qRT-PCR normalization in the Phytophthora-Q. suber pathosystem in root tissues. Those found to be more stable, QsRPII and QsCACs, were used as internal reference in the present work. Knowledge on the Quercus defence mechanisms against biotic stress is scarce. This study provides an insight into the gene profiling of a few important genes of Q. suber in response to P. cinnamomi infection contributing to the knowledge of the molecular interactions involving Quercus and root pathogens that can be useful in the future to understand the mechanisms underlying oak resistance to soil-borne oomycetes.

  11. RECRUITMENT FINANCED BY SAVED LEAVE (RSL PROGRAMME)

    CERN Multimedia

    Division du Personnel; Tel. 73903

    1999-01-01

    Transfer to the saved leave account and saved leave bonusStaff members participating in the RSL programme may opt to transfer up to 10 days of unused annual leave or unused compensatory leave into their saved leave account, at the end of the leave year, i.e. 30 September (as set out in the implementation procedure dated 27 August 1997).A leave transfer request form, which you should complete, sign and return, if you wish to use this possibility, has been addressed you. To allow the necessary time for the processing of your request, you should return it without delay.As foreseen in the implementation procedure, an additional day of saved leave will be granted for each full period of 20 days remaining in the saved leave account on 31 December 1999, for any staff member participating in the RSL programme until that date.For part-time staff members participating in the RSL programme, the above-mentioned days of leave (annual, compensatory and saved) are adjusted proportionally to their contractual working week as...

  12. Role of leaves in phototropism.

    Science.gov (United States)

    Lam, S L; Leopold, A C

    1966-05-01

    Experiments with green seedlings of sunflower (Helianthus annuns L.) indicate the existence of a phototropic mechanism which involves the leaves or cotyledons, and which can produce an asymmetry of auxin content without the involvement of lateral auxin transport, the classic explanation of phototropism in etiolated seedlings. The basic lines of evidence for the leaf-mediated tropism are: 1) darkening of one cotyledon will cause curvature of the stem toward the lighted cotyledon: 2) the darkened cotyledon sustains an enhanced growth rate in the stem below it: 3) conversely, light suppresses the growth-stimulating effects of a single cotyledon: and 4) more diffusible auxin is obtained from the stem below darkened cotyledons than below lighted ones.

  13. Foliar temperature-respiration response functions for broad-leaved tree species in the southern Appalachians.

    Science.gov (United States)

    Bolstad; Mitchell; Vose

    1999-11-01

    We measured leaf respiration in 18 eastern deciduous forest tree species to determine if there were differences in temperature-respiration response functions among species or among canopy positions. Leaf respiration rates were measured in situ and on detached branches for Acer pensylvanicum L., A. rubrum L., Betula spp. (B. alleghaniensis Britt. and B. lenta L.), Carya glabra (Mill.) Sweet, Cornus florida L., Fraxinus spp. (primarily F. americana L.), Liriodendron tulipifera L., Magnolia fraseri Walt., Nyssa sylvatica Marsh., Oxydendrum arboreum L., Platanus occidentalis L., Quercus alba L., Q. coccinea Muenchh., Q. prinus L., Q. rubra L., Rhododendron maximum L., Robinia psuedoacacia L., and Tilia americana L. in the southern Appalachian Mountains, USA. Dark respiration was measured on fully expanded leaves at 10, 15, 20, 25, and 30 degrees C with an infrared gas analyzer equipped with a temperature-controlled cuvette. Temperature-respiration response functions were fit for each leaf. There were significant differences in response functions among species and by canopy position within species. These differences were observed when respiration was expressed on a mass, nitrogen, or area basis. Cumulative nighttime leaf respiration was calculated and averaged over ten randomly selected nights for each leaf. Differences in mean cumulative nighttime respiration were statistically significant among canopy positions and species. We conclude that effects of canopy position and species on temperature-respiration response functions may need to be considered when making estimates of whole-tree or canopy respiration.

  14. Antimicrobial and antioxidative enrichment of oak (Quercus robur) bark by rotation planar extraction using ExtraChrom.

    Science.gov (United States)

    Andrensek, Samo; Simonovska, Breda; Vovk, Irena; Fyhrquist, Pia; Vuorela, Heikki; Vuorela, Pia

    2004-04-15

    The multifunctional ExtraChrom instrument was used in the extraction of antimicrobial and radical scavenging components from oak (Quercus robur L.) bark. Milled and sieved oak bark was extracted with 80% (v/v) methanol solution in water on the ExtraChrom instrument using step-gradient in the preparative separation. Extracts were tested using agar diffusion method on Staphylococcus aureus, Enterobacter aerogenes and Candida albicans. Some extracts showed moderate bactericidal, fungicidal, bacteriostatic and fungistatic activity. The composition related to activity of the fractions and extracts was screened simultaneously by thin-layer chromatography (TLC) detected by UV and by spraying the plate with radical scavenging reagent 1,1-diphenyl-2-picrylhydrazyl (DPPH) to detect antioxidant activity. Thus, we could demonstrate the antiradical and antimicrobial activity of oak beneficial in the storage of wine against the oxidation and human microbial exposure.

  15. Early growth of Quercus castaneifolia (C.A. Meyer) seedlings as affected by weeding, shading and irrigation.

    Science.gov (United States)

    Mirzaei, Javad; Tabari, Masoud; Daroodi, Hadi

    2007-08-01

    The influence of shading, irrigation and weeding on survival, growth and morphology of 1-year Quercus castaneifolia seedlings was studied in north of Iran. The seedlings were grown under eight treatments including full-light versus artificial shading, irrigation versus non-irrigation and weed presence versus weed removing at three replicates. At the end of the first growing season seedling survival in all treatments was 100%. Weed removing had positive effect on height, diameter growth, slenderness coefficient and leaf area of Q. castaneifolia. Irrigation enhanced diameter growth and leaf area and shading increased leaf area. Irrigation had no significant effect on plant growth where the weed was removed. In weed plots seedlings growth and leaf area were greater in shading than in full-light. The results indicated that for 1 year Q. castaneifolia seedlings, weeding, in contrast to irrigation, is an essential factor. Where the weed competition is a difficulty, plantation with higher stem length should be applied.

  16. Arquitectura foliar y anatomía de la corteza y la madera de Quercus sartorii y Q. xalapensis (Fagaceae)

    OpenAIRE

    Dorismilda Martínez Cabrera; Teresa Terrazas; Fernando Zavala Chávez

    2003-01-01

    En este trabajo se describe y compara la arquitectura foliar y la anatomía de la corteza y la madera de Quercus sartorii y Q. xalapensis, especies morfológicamente similares, en la búsqueda de caracteres que contribuyan a su delimitación. Los resultados mostraron que los caracteres del patrón de venación: número y forma de aréolas, ramificación de las vénulas y recorrido de la vena secundaria dentro del diente son caracteres que permiten distinguir a las especies, no así el tamaño de la hoja ...

  17. Variation of equilibrium moisture content of heat-treated Couratari oblongifolia, Fraxinus excelsior, and Quercus rubra wood

    Directory of Open Access Journals (Sweden)

    Qiaofang Zhou

    2013-02-01

    Full Text Available Heat treatment may result in variation of wood equilibrium moisture content (EMC. During this study, tauari (Couratari oblongifolia, ash (Fraxinus excelsior, and oak (Quercus rubra woods were heat-treated at 190, 200, and 210ºC for 3 hours and then put into a conditioning chamber with a temperature from 30 to 75ºC and a relative humidity from 50 to 90%. The isothermal moisture adsorption curve was subsequently analyzed. Results indicated that the EMC of heat-treated wood was reduced by 23.4 to 37.4% compared to non-treated wood, but the EMC difference at different heat-treated temperatures for three hardwoods was quite small and the EMC of heat-treated wood was inversely proportional to their dry density.

  18. Diplodia quercivora sp. nov.: a new species of Diplodia found on declining Quercus canariensis trees in Tunisia.

    Science.gov (United States)

    Linaldeddu, Benedetto T; Franceschini, Antonio; Alves, Artur; Phillips, Alan J L

    2013-01-01

    During a study of the species of Botryosphaeriaceae associated with oak decline in Tunisia, a large collection of Diplodia strains were isolated from Quercus afares, Q. canariensis and Q. suber trees showing a progressive dieback of shoots and branches, trunk canker and exudates and collar rot. Most of the isolates were identified as Diplodia corticola, while two isolates from Q. canariensis were morphologically and phylogenetically (ITS and tef1-α sequences data) distinct from all other known species of Diplodia. They are described here as Diplodia quercivora sp. nov. In addition, phylogenetic analyses showed for the first time the existence of two distinct lineages within D. corticola. In artificial inoculation experiments, D. quercivora caused necrotic lesions on bark and wood of three Mediterranean oak species, Q. ilex, Q. pubescens and Q. suber. In particular, among the oak species tested, Q. pubescens was the most susceptible.

  19. 欧洲栓皮栎种子催芽试验%Seed Germination Trial with Cork Oak (Quercus suber)

    Institute of Scientific and Technical Information of China (English)

    佘远国

    2000-01-01

    @@ 欧洲栓皮栎(Quercus rariabilis B1.)是一种重要的软木工业原料.60年代从苏联引种我省,由于疏于管理,目前,全省仅存100株,濒于绝迹.为了拯救优良物种,加大欧洲栓皮栎种质资源收集,加速物种繁殖.实生繁殖时,为了确定合理的播种量以及改进种子贮藏方法,对种子进行不同药剂催芽处理,测定发芽率,平均发芽速,根的生长量,比较不同药剂对种子发芽的影响效果.

  20. Biomass-diversity relations of epiphytic bryophytes on small Quercus copeyensis stems in a Costa Rican montane cloud forest

    Directory of Open Access Journals (Sweden)

    H.J.F. Van Dunné

    1998-06-01

    Full Text Available Se muestreó briófitas epífitas sobre tallos pequeños de Quercus copeyensis Müll. en un bosque montano nuboso maduro (Talamanca, Costa Rica. Se muetreó a 0.8-1.8 m en cinco tallos (d.a.p. 1.8 -2.8 cm, hallándose 22 especies de musgos y 22 de hepáticas. La biomasa de briófitas ("briomasa" se correlacionó con la frecuencia, contribuyendo los musgos 54-99% . Un 14% de las especies contribuyó casi el 90% de la briomasa, sobresaliendo Pilotrichella flexilis (Hedw. Ångstr., Rigodium sp. 1, Porotrichodendron superbum (Taylor Broth., Prionodon densus (Hedw. Müll. Hal., Neckera chilensis Schimp. ex Mont. y Plagiochila guilleminiana Nees & Mont. Estas especies podrían jugar un papel importante en la regulación del flujo de agua.

  1. Cooling experiments using dummies covered by leaves.

    Science.gov (United States)

    Althaus, L; Stückradt, S; Henssge, C; Bajanowski, T

    2007-03-01

    One main method to estimate the time of death is the measurement of the body temperature. The cooling of a corpse depends on a number of conditions including the surroundings. In cases where the cooling conditions differ from the defined standard, a corrective factor is used to characterise the influence of clothing, air movement, the properties of the supporting base and the humidity. Nothing is known about the significance of other circumstances, for example of a tegument by leaves or wet leaves. Therefore, the cooling of dummies which were placed on a 2-cm-thick layer of wet/dry leaves and covered by a 10-cm-thick layer of leaves was investigated. Corrective factors of 1.0 for wet leaves on the ground and of 1.3 and 1.5 for drier leaves were found. If the dummies were additionally covered, corrective factors ranged between 1.8 and 2.7.

  2. Spatial Segregation and Aggregation of Ectomycorrhizal and Root-Endophytic Fungi in the Seedlings of Two Quercus Species

    Science.gov (United States)

    Yamamoto, Satoshi; Sato, Hirotoshi; Tanabe, Akifumi S.; Hidaka, Amane; Kadowaki, Kohmei; Toju, Hirokazu

    2014-01-01

    Diverse clades of mycorrhizal and endophytic fungi are potentially involved in competitive or facilitative interactions within host-plant roots. We investigated the potential consequences of these ecological interactions on the assembly process of root-associated fungi by examining the co-occurrence of pairs of fungi in host-plant individuals. Based on massively-parallel pyrosequencing, we analyzed the root-associated fungal community composition for each of the 249 Quercus serrata and 188 Quercus glauca seedlings sampled in a warm-temperate secondary forest in Japan. Pairs of fungi that co-occurred more or less often than expected by chance were identified based on randomization tests. The pyrosequencing analysis revealed that not only ectomycorrhizal fungi but also endophytic fungi were common in the root-associated fungal community. Intriguingly, specific pairs of these ectomycorrhizal and endophytic fungi showed spatially aggregated patterns, suggesting the existence of facilitative interactions between fungi in different functional groups. Due to the large number of fungal pairs examined, many of the observed aggregated/segregated patterns with very low P values (e.g., fungi could influence each other through interspecific competitive/facilitative interactions in root. To test the potential of host-plants' control of fungus–fungus ecological interactions in roots, we further examined whether the aggregated/segregated patterns could vary depending on the identity of host plant species. Potentially due to the physiological properties shared between the congeneric host plant species, the sign of hosts' control was not detected in the present study. The pyrosequencing-based randomization analyses shown in this study provide a platform of the high-throughput investigation of fungus–fungus interactions in plant root systems. PMID:24801150

  3. Spatial segregation and aggregation of ectomycorrhizal and root-endophytic fungi in the seedlings of two Quercus species.

    Science.gov (United States)

    Yamamoto, Satoshi; Sato, Hirotoshi; Tanabe, Akifumi S; Hidaka, Amane; Kadowaki, Kohmei; Toju, Hirokazu

    2014-01-01

    Diverse clades of mycorrhizal and endophytic fungi are potentially involved in competitive or facilitative interactions within host-plant roots. We investigated the potential consequences of these ecological interactions on the assembly process of root-associated fungi by examining the co-occurrence of pairs of fungi in host-plant individuals. Based on massively-parallel pyrosequencing, we analyzed the root-associated fungal community composition for each of the 249 Quercus serrata and 188 Quercus glauca seedlings sampled in a warm-temperate secondary forest in Japan. Pairs of fungi that co-occurred more or less often than expected by chance were identified based on randomization tests. The pyrosequencing analysis revealed that not only ectomycorrhizal fungi but also endophytic fungi were common in the root-associated fungal community. Intriguingly, specific pairs of these ectomycorrhizal and endophytic fungi showed spatially aggregated patterns, suggesting the existence of facilitative interactions between fungi in different functional groups. Due to the large number of fungal pairs examined, many of the observed aggregated/segregated patterns with very low P values (e.g., fungi could influence each other through interspecific competitive/facilitative interactions in root. To test the potential of host-plants' control of fungus-fungus ecological interactions in roots, we further examined whether the aggregated/segregated patterns could vary depending on the identity of host plant species. Potentially due to the physiological properties shared between the congeneric host plant species, the sign of hosts' control was not detected in the present study. The pyrosequencing-based randomization analyses shown in this study provide a platform of the high-throughput investigation of fungus-fungus interactions in plant root systems.

  4. Using common mycorrhizal networks for controlled inoculation of Quercus spp. with Tuber melanosporum: the nurse plant method.

    Science.gov (United States)

    Pereira, Guillermo; Palfner, Götz; Chávez, Daniel; Suz, Laura M; Machuca, Angela; Honrubia, Mario

    2013-07-01

    The high cost and restricted availability of black truffle spore inoculum for controlled mycorrhiza formation of host trees produced for truffle orchards worldwide encourage the search for more efficient and sustainable inoculation methods that can be applied globally. In this study, we evaluated the potential of the nurse plant method for the controlled inoculation of Quercus cerris and Quercus robur with Tuber melanosporum by mycorrhizal networks in pot cultures. Pine bark compost, adjusted to pH 7.8 by liming, was used as substrate for all assays. Initially, Q. robur seedlings were inoculated with truffle spores and cultured for 12 months. After this period, the plants presenting 74 % mycorrhizal fine roots were transferred to larger containers. Nurse plants were used for two treatments of two different nursling species: five sterilized acorns or five 45-day-old, axenically grown Q. robur or Q. cerris seedlings, planted in containers around the nurse plant. After 6 months, colonized nursling plant root tips showed that mycorrhiza formation by T. melanosporum was higher than 45 % in the seedlings tested, with the most successful nursling combination being Q. cerris seedlings, reaching 81 % colonization. Bulk identification of T. melanosporum mycorrhizae was based on morphological and anatomical features and confirmed by sequencing of the internal transcribed spacer region of the ribosomal DNA of selected root tips. Our results show that the nurse plant method yields attractive rates of mycorrhiza formation by the Périgord black truffle and suggest that establishing and maintaining common mycorrhizal networks in pot cultures enables sustained use of the initial spore inoculum.

  5. Abundancia y distribución de agallas foliosas en Quercus resinosa Liemb. (Fagaceae en Aguascalientes, México

    Directory of Open Access Journals (Sweden)

    Ricardo Clark-Tapia

    2015-08-01

    Full Text Available Las agallas son estructuras de crecimiento anormal en los tejidos de las plantas debido a la actividad parasítica de otro organismo. El estudio de este tipo de estructuras como microhábitat de avispas es escaso en la literatura y no se presenta una descripción detallada de su conformación. En este trabajo se describe la anatomía y morfología de las agallas foliosas, y se evalúan los factores que restringen su abundancia y distribución a nivel foliar, individual y poblacional en los encinosQuercus resinosa. Se encontró que la agalla es generada por una avispa de la familia Cynipidae, específica deQuercus resinosaLiemb. A nivel foliar, las agallas presentan características anatómicas y morfológicas similares a las del hospedero. A nivel del individuo, el 72.52% de las agallas están ubicadas en el envés de la hoja, mientras que sólo el 27.48% de estas estructuras se forman en el haz. A nivel de la población, el número de agallas varía de una a diez agallas por árbol. En promedio, cada árbol puede tener 4.88 ± 2.34 agallas. Los árboles mayormente infectados son los de categorías intermedias (X2=9.67; P

  6. Does animal-mediated seed dispersal facilitate the formation of Pinus armandii-Quercus aliena var. acuteserrata forests?

    Directory of Open Access Journals (Sweden)

    Fei Yu

    Full Text Available The Pinus armandii and Quercus aliena var. acuteserrata mixed forest is one of the major forest types in the Qinling Mountains, China. P. armandii is considered to be a pioneer species during succession and it is usually invaded by late successional Q. aliena var. acuteserrata. However, the mechanism that underlies its invasion remains unclear. In the present study, we tracked seed dispersal of P. armandii and Q. aliena var. acuteserrata using coded plastic tags in the western, middle and eastern Qinling Mountains to elucidate the invasion process in the mixed forests. Our results indicated that the seeds of both P. armandii and Q. aliena var. acuteserrata were removed rapidly in the Qinling Mountains, and there were no differences in the seed removal rates between the two species. There were significant differences in rodent seed-eating and caching strategies between the two tree species. For P. armandii, seeds were more likely to be eaten in situ than those of Q. aliena var. acuteserrata in all plots. By contrast, the acorns of Q. aliena var. acuteserrata were less frequently eaten in situ, but more likely to be removed and cached. Q. aliena var. acuteserrata acorns had significantly longer dispersal distances than P. armandii seeds in all plots. Although P. armandii seeds were less likely to be dispersed into the Q. aliena var. acuteserrata stands, over 30% of the released acorns were transported into the P. armandii stands where they established five seedlings. Based on the coupled recruitment patterns of P. armandii and Q. aliena var. acuteserrata, we suggest that the animal-mediated seed dispersal contributes to the formation of Pinus armandii-Quercus aliena var. acuteserrata forests.

  7. Tree species richness, diversity, and regeneration status in different oak (Quercus spp. dominated forests of Garhwal Himalaya, India

    Directory of Open Access Journals (Sweden)

    Sushma Singh

    2016-09-01

    Full Text Available Himalayan forests are dominated by different species of oaks (Quercus spp. at different altitudes. These oaks are intimately linked with hill agriculture as they protect soil fertility, watershed, and local biodiversity. They also play an important role in maintaining ecosystem stability. This work was carried out to study the diversity and regeneration status of some oak forests in Garhwal Himalaya, India. A total of 18 tree species belonging to 16 genera and 12 families were reported from the study area. Species richness varied for trees (4–7, saplings (3–10, and seedlings (2–6. Seedling and sapling densities (Ind/ha varied between 1,376 Ind/ha and 9,600 Ind/ha and 167 Ind/ha and 1,296 Ind/ha, respectively. Species diversity varied from 1.27 to 1.86 (trees, from 0.93 to 3.18 (saplings, and from 0.68 to 2.26 (seedlings. Total basal area (m2/ha of trees and saplings was 2.2–87.07 m2/ha and 0.20–2.24 m2/ha, respectively, whereas that of seedlings varied from 299 cm2/ha to 8,177 cm2/ha. Maximum tree species (20–80% had “good” regeneration. Quercus floribunda, the dominant tree species in the study area, showed “poor” regeneration, which is a matter of concern, and therefore, proper management and conservation strategies need to be developed for maintenance and sustainability of this oak species along with other tree species that show poor or no regeneration.

  8. Paid Maternity Leave and Breastfeeding Outcomes.

    Science.gov (United States)

    Mirkovic, Kelsey R; Perrine, Cria G; Scanlon, Kelley S

    2016-09-01

    Despite the benefits of breastfeeding, rates in the United States are low. Shorter maternity leave is associated with lower initiation and shorter durations of breastfeeding; however, little is known about how paid maternity leave may influence breastfeeding rates. We used data from the 2006-2010 U.S. National Survey of Family Growth on the most recent birth to employed women who delivered a child within the previous 5 years. Separate multivariable logistic regression models were used to describe the associations between paid leave duration (0, 1-5, 6-11, ≥ 12 weeks, maternity leave not taken) and three outcomes: 1) breastfeeding initiation, 2) 6-month duration, and 3) 6-month duration among initiators. Twenty-eight percent of prenatally employed women received no paid leave. Women who received 12 or more weeks of paid leave were more likely to initiate breastfeeding compared to women with no paid leave (87.3% vs 66.7%, adjusted odds ratio [aOR] 2.83 [95% confidence interval {CI} 1.23-6.48]). Similarly, women with 12 or more weeks of paid leave were more likely to breastfeed at 6 months, compared to women with no paid leave (24.9% vs 50.1%, aOR 2.26 [95% CI 1.20-4.26]). Among women who initiated breastfeeding, having received 12 or more weeks' paid leave increased the odds of breastfeeding for 6 or more months; however, the association was not statistically significant in the adjusted model (aOR 1.81 [95% CI 0.93-3.52]). Employed women who received 12 or more weeks of paid maternity leave were more likely to initiate breastfeeding and be breastfeeding their child at 6 months than those without paid leave. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

  9. Wettability, Polarity, and Water Absorption of Holm Oak Leaves: Effect of Leaf Side and Age1[OPEN

    Science.gov (United States)

    Fernández, Victoria; Sancho-Knapik, Domingo; Guzmán, Paula; Peguero-Pina, José Javier; Gil, Luis; Karabourniotis, George; Khayet, Mohamed; Fasseas, Costas; Heredia-Guerrero, José Alejandro; Heredia, Antonio; Gil-Pelegrín, Eustaquio

    2014-01-01

    Plant trichomes play important protective functions and may have a major influence on leaf surface wettability. With the aim of gaining insight into trichome structure, composition, and function in relation to water-plant surface interactions, we analyzed the adaxial and abaxial leaf surface of holm oak (Quercus ilex) as a model. By measuring the leaf water potential 24 h after the deposition of water drops onto abaxial and adaxial surfaces, evidence for water penetration through the upper leaf side was gained in young and mature leaves. The structure and chemical composition of the abaxial (always present) and adaxial (occurring only in young leaves) trichomes were analyzed by various microscopic and analytical procedures. The adaxial surfaces were wettable and had a high degree of water drop adhesion in contrast to the highly unwettable and water-repellent abaxial holm oak leaf sides. The surface free energy and solubility parameter decreased with leaf age, with higher values determined for the adaxial sides. All holm oak leaf trichomes were covered with a cuticle. The abaxial trichomes were composed of 8% soluble waxes, 49% cutin, and 43% polysaccharides. For the adaxial side, it is concluded that trichomes and the scars after trichome shedding contribute to water uptake, while the abaxial leaf side is highly hydrophobic due to its high degree of pubescence and different trichome structure, composition, and density. Results are interpreted in terms of water-plant surface interactions, plant surface physical chemistry, and plant ecophysiology. PMID:24913938

  10. Tendencias en la investigación sobre ecología y gestión de las especies de Quercus

    Directory of Open Access Journals (Sweden)

    T. Marañón

    2014-01-01

    Full Text Available El género Quercus reúne algunas de las especies arbóreas más relevantes en los bosques del hemisferio norte, tanto por su amplia distribución geográfica como por su gran importancia ecológica y económica. Algunas de estas especies han sido y continúan siendo foco central en numerosos estudios científicos relacionados con la ecología y gestión de ecosistemas forestales. Los objetivos de este artículo son: 1 conocer la evolución del número de artículos relacionados con Quercus, así como los países y autores con mayor producción científica en este campo, 2 identificar los principales temas de investigación sobre las especies de Quercus de España y 3 discutir los huecos en el conocimiento y proponer algunas líneas futuras de investigación. Según la base de datos ISI Web of Science se han publicado 13 469 artículos relacionados con las especies de Quercus, con un crecimiento exponencial a lo largo del tiempo. España ocupa el segundo lugar en cuanto a número de artículos publicados (11.6 % del total, después de los Estados Unidos. Entre los 24 090 autores de artículos relacionados con Quercus, cinco españoles se encuentran entre los 20primeros en número de publicaciones. Dentro de las publicaciones sobre Quercus en España, la especie con mayor interés es la encina (Q. ilex,46.5 % de los artículos y los temas a los que se ha prestado más atención son: el cambio climático, la regeneración, los efectos de la sequía, las perturbaciones y la riqueza de especies. Se discuten los huecos de conocimiento detectados (en base a encuestas de expertos y se proponen líneas de investigación futuras relacionadas con el cambio global, la demografía, la eco fisiología, las interacciones bióticas y la gestión.

  11. The taxonomy of the Japanese oak red scale insect, Kuwania quercus (Kuwana) (Hemiptera: Coccoidea: Kuwaniidae), with a generic diagnosis, a key to species and description of a new species from California.

    Science.gov (United States)

    San'An, Wu; Nan, Nan; Gullan, Penny; Deng, Jun

    2013-01-01

    The oak red scale insect, Kuwania quercus (Kuwana), was described from specimens collected from the bark of oak trees (Quercus species) in Japan. More recently, the species has been identified from California and China, but Californian specimens differ morphologically from Japanese material and are considered here to be a new species based on both morphological and molecular data. In this paper, an illustrated redescription of K. quercus is provided based on type specimens consisting of adult females, first-instar nymphs and intermediate-stage females, and a lectotype is designated for Sasakia quercus Kuwana. The new Californian species, Kuwania raygilli Wu & Gullan, is described and illustrated based on the adult female, first-instar nymph and intermediate-stage female. A new generic diagnosis for Kuwania Cockerell based on adult females and first-instar nymphs, and a key to species based on adult females are included.

  12. Recovery of protein from green leaves

    NARCIS (Netherlands)

    Tamayo Tenorio, Angelica; Gieteling, Jarno; Jong, De Govardus A.H.; Boom, Remko M.; Goot, Van Der Atze J.

    2016-01-01

    Plant leaves are a major potential source of novel food proteins. Till now, leaf protein extraction methods mainly focus on the extraction of soluble proteins, like rubisco protein, leaving more than half of all protein unextracted. Here, we report on the total protein extraction from sugar beet

  13. 20 CFR 638.532 - Annual leave.

    Science.gov (United States)

    2010-04-01

    ... regardless of the date of enrollment provided that the student was not AWOL or on administrative leave without pay from the date of enrollment. Accrual time shall begin on the day the student departs for a... only once per year of enrollment. (e) Students shall not be charged annual leave for travel time to...

  14. A Feminist Perspective on Parental Leave Policies

    Science.gov (United States)

    Sallee, Margaret W.

    2008-01-01

    This article focuses on the ways that three feminist theories--liberal feminism, cultural feminism, and feminist poststructuralism--might be used to craft parental leave policies. After examining each theory in detail, the article concludes by offering one example of an ideal parental leave policy that combines the best features of each theory to…

  15. A new class of non-leaves

    CERN Document Server

    Souza, Fábio S

    2011-01-01

    We give examples of open smooth manifolds that cannot be leaves of any Riemannian foliation of arbitrary codimension on a compact manifold. We also present a new class of non-leaves of C^0 codimension one foliations, simply connected manifolds of dimension at least 5 that are non-periodic in homotopy, namely in their 2-dimensional homotopy groups.

  16. A Feminist Perspective on Parental Leave Policies

    Science.gov (United States)

    Sallee, Margaret W.

    2008-01-01

    This article focuses on the ways that three feminist theories--liberal feminism, cultural feminism, and feminist poststructuralism--might be used to craft parental leave policies. After examining each theory in detail, the article concludes by offering one example of an ideal parental leave policy that combines the best features of each theory to…

  17. INTRODUCTION OF A NEW LEAVE MANAGEMENT SYSTEM

    CERN Document Server

    DIVISION HR

    2000-01-01

    The introduction of new leave rules (arising from the RSL, PRP and other programs) has made the present leave management system rather complicated and difficult to manage. It has therefore been decided to replace it with a more flexible and adaptable system, which will come into force on 1st October 2000. Henceforth, days of leave will be credited monthly instead of annually. Members of the personnel will have round-the-clock direct access to more detailed, confidential information regarding their various kinds of leave. They will also receive a personal monthly statement with their pay slips. The new system does not require any amendment of the regulations, except with respect to the frequency of leave calculations (monthly instead of annual). I. Main characteristics of the new leave system1. The main feature of the new system is the creation of accounts to which leave will be credited or debited as appropriate. Depending on their circumstances, members of the personnel may have up to four individual leave a...

  18. INTRODUCTION OF A NEW LEAVE MANAGEMENT SYSTEM

    CERN Multimedia

    HR Division

    2000-01-01

    The introduction of new leave rules (arising from the RSL, PRP and other programmes) has made the present leave management system rather complicated and difficult to manage. It has therefore been decided to replace it with a more flexible and adaptable system, which will come into force on 1st October 2000. Henceforth, days of leave will be credited monthly instead of annually. Members of the personnel will have round-the-clock direct access to more detailed, confidential information regarding their various kinds of leave.They will also receive a personal monthly statement with their pay slips. The new system does not require any amendment of the regulations, except with respect to the frequency of leave calculations (monthly instead of annual). I. Main characteristics of the new leave system 1. The main feature of the new system is the creation of accounts to which leave will be credited or debited as appropriate. Depending on their circumstances, members of the personnel may have up to four individual leave...

  19. [Beneficial effect of maternity leave on delivery].

    Science.gov (United States)

    Xu, Qian; Séguin, Louise; Goulet, Lise

    2002-01-01

    To identify the contribution of the duration of the prenatal maternity leave on term delivery. Characteristics of the prenatal maternity leave and delivery among 363 working women who had delivered a full-term infant at 1 of 4 hospitals in Montreal during 1996 were studied. The presence of an intervention or complication during delivery was observed in 68.9% of the participants. The average duration of the prenatal maternity leave was about 8 weeks (SD = 7). The adjusted risk of a difficult delivery decreased significantly with the duration of the prenatal maternity leave (OR = 0.96; 95% CI: 0.93-0.99). The duration of the maternity leave before delivery is associated with an easier term delivery for working women.

  20. Sap flow measurements combining sap-flux density radial profiles with punctual sap-flux density measurements in oak trees (Quercus ilex and Quercus pyrenaica) - water-use implications in a water-limited savanna-

    Science.gov (United States)

    Reyes, J. Leonardo; Lubczynski1, Maciek W.

    2010-05-01

    Sap flow measurement is a key aspect for understanding how plants use water and their impacts on the ecosystems. A variety of sensors have been developed to measure sap flow, each one with its unique characteristics. When the aim of a research is to have accurate tree water use calculations, with high temporal and spatial resolution (i.e. scaled), a sensor with high accuracy, high measurement efficiency, low signal-to-noise ratio and low price is ideal, but such has not been developed yet. Granier's thermal dissipation probes (TDP) have been widely used in many studies and various environmental conditions because of its simplicity, reliability, efficiency and low cost. However, it has two major flaws when is used in semi-arid environments and broad-stem tree species: it is often affected by high natural thermal gradients (NTG), which distorts the measurements, and it cannot measure the radial variability of sap-flux density in trees with sapwood thicker than two centimeters. The new, multi point heat field deformation sensor (HFD) is theoretically not affected by NTG, and it can measure the radial variability of the sap flow at different depths. However, its high cost is a serious limitation when simultaneous measurements are required in several trees (e.g. catchment-scale studies). The underlying challenge is to develop a monitoring schema in which HFD and TDP are combined to satisfy the needs of measurement efficiency and accuracy in water accounting. To assess the level of agreement between TDP and HFD methods in quantifying sap flow rates and temporal patterns on Quercus ilex (Q.i ) and Quercus pyrenaica trees (Q.p.), three measurement schemas: standard TDP, TDP-NTG-corrected and HFD were compared in dry season at the semi-arid Sardon area, near Salamanca in Spain in the period from June to September 2009. To correct TDP measurements with regard to radial sap flow variability, a radial sap flux density correction factor was applied and tested by adjusting TDP

  1. Comparison of the autoecology of Quercus robur L. and Q. petraea (Mattuschka Liebl. stands in the Northwest of the Iberian Peninsula

    Directory of Open Access Journals (Sweden)

    A. Rodriguez-Campos

    2010-09-01

    Full Text Available The purpose of the present work is to characterize the functioning of the ecosystems of semideciduous and deciduous Atlantic oaks in the northwest of the Iberian Peninsula. The studied species were: Quercus robur L. and Quercus petraea (Mattuschka Liebl. To advance in the knowledge of the autecology of these species it is necessary to descend at the regional level and describe in detail the variability of the environment to determine their potential, and to decide the silvicultural treatments to be applied to preserve them and to analyze future actuations in order to a possible expansion. The analysis of the results allows knowing differences in continentalityand site conditions, with more precipitation, soil variability and humidification in Q. petraea forests respect to Q. robur. These information represent appropriate measures for the sustainable and multifunctional management of these forests, useful as indicators environmental and forestry parameters as well as the conservationstatus of these formations.

  2. Datos históricos de la presencia de fitónimos relacionados con el género Quercus L. en Canarias

    Directory of Open Access Journals (Sweden)

    Marcos Salas Pascual

    2013-11-01

    Full Text Available En el presente trabajo se discute la posible presencia histórica de algunas especies del género Quercus L. en Canarias. Se utilizan para ello referencias documentales y toponímicas, así como citas botánicas antiguas. De esta manera se plantea la posibilidad de que existiesen poblaciones distintas especies de este género en Fuerteventura y Tenerife.Presently work is discussed the possible historical presence of some species of the gender Quercus L. in Canarias. They are used for this toponimic and documental references, as well as botanical old appointments. This way thinks about the possibility that some species of this gender could grow in Fuerteventura and Tenerife.

  3. Drought impact on carbon and water cycling in a Mediterranean Quercus suber L. woodland during the extreme drought event in 2012

    Science.gov (United States)

    Piayda, Arndt; Dubbert, Maren; Rebmann, Corinna; Kolle, Olaf; Silva, Filipe Costa e.; Correia, Alexandra; Pereira, João S.; Werner, Christiane; Cuntz, Matthias

    2015-04-01

    Savannah-type ecosystems account for 26-30% of global gross primary productivity GPP, with water being one of the major driving factors. In Europe, savannah-type woodlands cover an area of about 1.5 million ha. Here, the recent past has shown a significant decrease in precipitation P in winter and spring as well as a decrease in total annual precipitation. Strong effects on local water balance and carbon sink strength have thus been reported due to changes in precipitation regime. The objective of this study is to quantify the impact of the extreme drought event in 2012 on the water balance, gross primary productivity and carbon sink strength of a typical Portuguese cork-oak woodland (montado) compared to the wet year of 2011. Physiological responses of the dominant tree species Quercus suber (L.) are disentangled employing combined photosynthesis and stomatal conductance modelling. Precipitation effectiveness ET/P increased from 86% in 2011 to 122% in the 2012 dry year due to deep soil or groundwater access of the Q. suber trees leaving no water for groundwater replenishment. Understorey and overstorey GPP were strongly reduced, by 53 and 28%, respectively, in 2012 compared to 2011, due to the late onset of the autumn rains in 2011 and an additional severe winter/spring drought. However, the ecosystem was still a carbon sink in both years, but with a 38% reduced sink strength under extreme drought in 2012 compared to 2011. The combined photosynthesis-stomatal conductance model yielded the best results if it was allowed to adjust photosynthetic and stomatal parameters simultaneously. If stomatal response was modelled with the Leuning approach, which allows for a different sensitivity to vapour pressure deficit, the stomatal model parameters were highly coupled. A change in either of the parameters needed to be compensated by the other to guarantee a stable sensitivity of stomatal conductance to assimilation, independent of variations in vapour pressure deficit. The

  4. Drought impact on carbon and water cycling in a Mediterranean Quercus suber L. woodland during the extreme drought event in 2012

    Directory of Open Access Journals (Sweden)

    A. Piayda

    2014-07-01

    Full Text Available Savannah-type ecosystems account for 26–30% of global gross primary productivity GPP with water being one of the major driving factors. In Europe, savannah-type woodlands cover an area of about 1.5 million ha. Here, the recent past has shown a significant decrease of precipitation P in winter and spring as well as decrease of total annual precipitation. Strong effects on local water balance and carbon sink strength have thus been reported due to changes in precipitation regime. The objective of this study is to quantify the impact of the extreme drought event in 2012 on the water balance, gross primary productivity and carbon sink strength of a typical Portuguese cork-oak woodland (montado compared to the wet year 2011. Physiological responses of the dominant tree species Quercus suber (L. are disentangled, employing combined photosynthesis and stomatal conductance modelling. Precipitation effectiveness ET / P increased from 86% in 2011 to 122% in the dry year 2012 due to deep soil or ground water access of the Q. suber trees leaving no water for ground water replenishment. Understorey and overstorey GPP were strongly reduced by 53% and 28%, respectively, in 2012 compared to 2011 due to the late onset of the autumn rains in 2011 and an additional severe winter/spring drought. However, the ecosystem was still a carbon sink in both years but with a 38% reduced sink strength under extreme drought in 2012 compared to 2011. The combined photosynthesis-stomatal conductance model yielded best results if it was allowed to adjust photosynthetic and stomatal parameters simultaneously. If stomatal response was modelled with the Leuning approach, which allows for a different sensitivity to vapour pressure deficit, the stomatal model parameters were highly coupled. A change in either of the parameters needed to be compensated by the other to guarantee a stable sensitivity of stomatal conductance to assimilation, independently from variations in vapour

  5. The Geographic Distribution of a Tropical Montane Bird Is Limited by a Tree: Acorn Woodpeckers (Melanerpes formicivorus) and Colombian Oaks (Quercus humboldtii) in the Northern Andes.

    Science.gov (United States)

    Freeman, Benjamin G; Mason, Nicholas A

    2015-01-01

    Species distributions are limited by a complex array of abiotic and biotic factors. In general, abiotic (climatic) factors are thought to explain species' broad geographic distributions, while biotic factors regulate species' abundance patterns at local scales. We used species distribution models to test the hypothesis that a biotic interaction with a tree, the Colombian oak (Quercus humboldtii), limits the broad-scale distribution of the Acorn Woodpecker (Melanerpes formicivorus) in the Northern Andes of South America. North American populations of Acorn Woodpeckers consume acorns from Quercus oaks and are limited by the presence of Quercus oaks. However, Acorn Woodpeckers in the Northern Andes seldom consume Colombian oak acorns (though may regularly drink sap from oak trees) and have been observed at sites without Colombian oaks, the sole species of Quercus found in South America. We found that climate-only models overpredicted Acorn Woodpecker distribution, suggesting that suitable abiotic conditions (e.g. in northern Ecuador) exist beyond the woodpecker's southern range margin. In contrast, models that incorporate Colombian oak presence outperformed climate-only models and more accurately predicted the location of the Acorn Woodpecker's southern range margin in southern Colombia. These findings support the hypothesis that a biotic interaction with Colombian oaks sets Acorn Woodpecker's broad-scale geographic limit in South America, probably because Acorn Woodpeckers rely on Colombian oaks as a food resource (possibly for the oak's sap rather than for acorns). Although empirical examples of particular plants limiting tropical birds' distributions are scarce, we predict that similar biotic interactions may play an important role in structuring the geographic distributions of many species of tropical montane birds with specialized foraging behavior.

  6. Chronic Drought Decreases Anabolic and Catabolic BVOC Emissions of Quercus pubescens in a Mediterranean Forest

    Science.gov (United States)

    Saunier, Amélie; Ormeño, Elena; Wortham, Henri; Temime-Roussel, Brice; Lecareux, Caroline; Boissard, Christophe; Fernandez, Catherine

    2017-01-01

    Biogenic volatile organic compounds (BVOC) emitted by plants can originate from both anabolism (metabolite production through anabolic processes) and catabolism (metabolite degradation by oxidative reactions). Drought can favor leaf oxidation by increasing the oxidative pressure in plant cells. Thus, under the precipitation decline predicted for the Mediterranean region, it can be expected both strong oxidation of anabolic BVOC within leaves and, as a result, enhanced catabolic BVOC emissions. Using an experimental rain exclusion device in a natural forest, we compared the seasonal course of the emissions of the main anabolic BVOC released by Q. pubescens (isoprene and methanol) and their catabolic products (MACR+MVK+ISOPOOH and formaldehyde, respectively) after 3 years of precipitation restriction (−30% of rain). Thus, we assume that this repetitive amplified drought promoted a chronic drought. BVOC emissions were monitored, on-line, with a PTR-ToF-MS. Amplified drought decreased all BVOC emissions rates in spring and summer by around 40–50 %, especially through stomatal closure, with no effect in autumn. Moreover, ratios between catabolic and anabolic BVOC remained unchanged with amplified drought, suggesting a relative stable oxidative pressure in Q. pubescens under the water stress applied. Moreover, these results suggest a quite good resilience of this species under the most severe climate change scenario in the Mediterranean region. PMID:28228762

  7. Development of gypsy moth (Lymantria dispar L on the foliage of Quercus cerris L., Q. Petraea (matt Liebl. and Q. Robur L. in the controlled conditions

    Directory of Open Access Journals (Sweden)

    Milanović Slobodan

    2007-01-01

    Full Text Available The development of Gypsy moth (Lymantria dispar L was monitored in laboratory conditions, on the foliage of the species Quercus cerris L. Quercus petraea (Matt Liebl. and Quercus robur L. The experiment was established in the controlled environmental conditions, at the temperature of 25°C, photoperiod 14:10 (day: night and relative humidity 70%. The objective of the research was to determine the suitability of the study host plant species for gypsy moth development. The study results show that Gypsy moth caterpillars cultivated on Q. petraea foliage had a lower survival, higher number of moultings, longer preadult development and lower fecundity, which makes this species less suitable compared to the other two. Gypsy moth caterpillars cultivated on Q. cerris foliage had the highest survival degree the lowest number of moultings, the shortest preadult development and the highest fecundity, which makes this species the most favourable for gypsy moth development. Q. robur was between the former two species in this respect.

  8. Contrasting nuclear and cytoplasmic exchanges between phylogenetically distant oak species (Quercus suber L. and Q. ilex L.) in Southern France: inferring crosses and dynamics.

    Science.gov (United States)

    Mir, C; Jarne, P; Sarda, V; Bonin, A; Lumaret, R

    2009-03-01

    Gene flow is particularly frequent in the genus Quercus (oaks), especially between closely related species. We focus here on Quercus ilex and the cork-producing Quercus suber, which occasionally hybridize although they are phylogenetically markedly separated. Morphological observations were combined with both allozymic and chloroplastic diagnostic markers to characterize hybridization and introgression and to infer their dynamics in two French regions (French Catalonia and Provence), which are separated by several hundred kilometres. Some hybrids were found in both regions, indicating recent hybridization events. As expected from previous studies, most hybrids resulted from female symbol Q. ilex x male symbol Q. suber crosses, but our data showed that the reciprocal cross is also possible. Partial independence between nuclear and chloroplastic introgression was observed in the two species. Nuclear introgression was limited in both species and both regions, with no preferred direction. In Provence, chloroplastic introgression was very rare in both species. Conversely, all Q. suber individuals from French Catalonia were introgressed by Q. ilex chlorotypes. This might be explained by introgression in the Iberian Peninsula antedating the first occurrence of the two species in French Catalonia. We also observed a new chlorotype that was created locally, and was exchanged between the two species. However, the two species still remain genetically differentiated. The dynamics and complexity of exchanges and the factors determining them (including human management of Q. suber) are discussed.

  9. Influence of maternity leave on exclusive breastfeeding.

    Science.gov (United States)

    Monteiro, Fernanda R; Buccini, Gabriela Dos S; Venâncio, Sônia I; da Costa, Teresa H M

    To describe the profile of women with children aged under 4 months living in the Brazilian state capitals and in the Federal District according to their working status and to analyze the influence of maternity leave on exclusive breastfeeding (EBF) among working women. This was a cross-sectional study with data extracted from the II National Maternal Breastfeeding Prevalence Survey carried out in 2008. Initially, a descriptive analysis of the profile of 12,794 women was performed, according to their working status and maternity leave and the frequency of maternity leave in the Brazilian regions and capitals. The study used a multiple model to identify the influence of maternity leave on EBF interruption, including 3766 women who declared they were working and were on maternity leave at the time of the interview. The outcome assessed in the study was the interruption of the EBF, classified by the WHO. Regarding the working status of the mothers, 63.4% did not work outside of their homes and among those who worked, 69.8% were on maternity leave. The largest prevalence among workers was of women older than 35 years of age, with more than 12 years of schooling, primiparous and from the Southeast and South regions. The lack of maternity leave increased by 23% the chance of EBF interruption. Maternity leave contributed to increase the prevalence of EBF in the Brazilian states capitals, supporting the importance of increasing the maternity leave period from four to six months. Copyright © 2017 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

  10. Redimiento de Quercus humboldtii Bonpland (Roble en condiciones de interacción micorrizas ectotróficas - humus

    Directory of Open Access Journals (Sweden)

    Zarate Quiroga Lyda Minelly

    2002-11-01

    Full Text Available Se evaluó el rendimiento de Quercus humboldtii(roble en hidroponía de soporte sólido (virutade madera a través del análisis de las variables peso seco (g, peso fresco (g, altura (cm, áreafoliar (cm2, índice foliar específico (IF, cm2/g y tasa de asimilación neta (TAN, g/cm2*días,en dos fases, durante 14 meses, así: en la fase 1 (10 meses se aplicó inóculo ectomicorrízico,posteriormente se comprobó la colonización por ectomicorrizas (ECM. Se encontró diferenciaestadísticamente significativa (95% de confianza entre los 2 tratamientos (con y sin ECM, endonde las plantas ectomicorrizadas presentan incrementos en las variables evaluadas. En lafase 2 (4 meses, se adicionaron 5 humus, disímiles en los contenidos de elementos y pH, perocon valores de capacidad de intercambio catiónico (CIC altos (superiores a 25 meq/100g.A los tratamientos (12, resultado de combinar árboles con y sin ECM con cada uno de loshumus, se les confirmó la presencia de ECM y mostraron diferencias significativas (95% deconfianza, en donde se vió que la interacción ECM - humus genera los mejores rendimientos,y que la ectomicorriza actúa como reguladora de los cambios en la disponibilidad de elementosen el medio. Los análisis de elementos a nivel foliar mostraron una amplia tolerancia del roblepara macro y micro elementos, desde valores bajos a altos, según los referentes empleados. Seestableció un sistema interactuante soporte - raíz - ECM - humus, que permite una adecuadadinámica nutricional. Se analizó el inóculo ectomicorrízico (obtenido de árboles en condicionesde campo, y se obtuvo por morfotipificación la caracterización de 12 morfotipos, más uno delensayo de rendimiento. Al contrastar los morfotipos obtenidos con los árboles fuente se corro-boró el comportamiento poli-simbióntico de la especie. Se encontraron las condiciones necesa-rias para establecer hidroponía en medio líquido de Quercus humboldtii.

  11. 5 CFR 550.1207 - Recrediting annual leave.

    Science.gov (United States)

    2010-01-01

    ... of title 5, United States Code, but is covered by a different leave system, the employing agency must... leave than can be recredited under the different leave system, the employee must refund only the amount... formal leave system to which his or her annual leave can be recredited, the employing agency...

  12. 5 CFR 630.502 - Sick leave recredit.

    Science.gov (United States)

    2010-01-01

    ... different leave systems under section 6308 of title 5, United States Code, 7 calendar days of sick leave are... leave system to which he or she can transfer only a part of his or her sick leave is entitled to a... employee returns to the leave system under which it was earned on or after December 2, 1994. (f)...

  13. 5 CFR 630.1206 - Notice of leave.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Notice of leave. 630.1206 Section 630.1206 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS ABSENCE AND LEAVE Family and Medical Leave § 630.1206 Notice of leave. (a) If leave taken under § 630.1203(a)...

  14. 5 CFR 630.703 - Computation of shore leave.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Computation of shore leave. 630.703 Section 630.703 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS ABSENCE AND LEAVE Shore Leave § 630.703 Computation of shore leave. (a) An employee earns shore leave at...

  15. Labour supply responses to paid parental leave

    OpenAIRE

    Karimi, Arizo; Lindahl, Erica; Skogman Thoursie , Peter

    2012-01-01

    Women account for the majority of parental leave take-up, which is likely one of the major reasons for the gender gap in income and wages. Consequently, many countries exert effort to promote a more gender equal division of parental leave. Indeed, the last decades have seen an increase in fathers’ take-up of parental leave benefits, but the gender earnings gap has remained fairly constant. In this paper we re-evaluate the labour supply responses of both mothers and fathers to three major refo...

  16. Mycorrhizal status of several Quercus species in Romania (Quercus cerris, Q. frainetto, Q. robur and the optimization perspective of growth conditions for in vitro propagated plants transplanted in the field

    Directory of Open Access Journals (Sweden)

    Ecaterina Fodor

    2011-06-01

    Full Text Available There is an increasing interest for important tree species conservation in the context of climate change, anthropogenic pressure and invasion of alien tree species. A key factor in the survival of trees is represented by the mycorrhizal association. The success of micropropagated trees also depends on the acquisition of mycorrhizal mutualists. Ectomycorrhizal roots samples from several Quercus species (Q. cerris, Q. frainetto, Q. robur were examined for mycorrhizal morphotypes’ characterization. The samples were collected during the vegetation season from stands located in Southern and North-Western Romania. 30 morphotypes of active mycorrhizae were identified with Cenococcum geophilumFr. (Ascomycota as dominating morphotype. Previous studies on somatic embryogenesis in Q. roburand Q. frainetto demonstrated the utility of in vitro techniques in obtaining plants from these recalcitrant seed producing species, considered at risk in various areas of the country, due to increasingly stressful conditions. The success rate of the acclimatization process depends on the mycorrhization performed either artificially, in the laboratory, either naturally, in the field. Ex situ mycorrhization solutions are considered as less costly, yet efficient alternative to improve the ex vitro survival of micropropagated plants or endangered tree species or for those with economic importance, in vitro propagation is an important conservation tool combined with the acquisition of appropriate mycorrhizal mutualists. 

  17. Mycorrhizal status of several Quercus species in Romania (Quercus cerris, Q. frainetto, Q. robur and the optimization perspective of growth conditions for in vitro propagated plants transplanted in the field

    Directory of Open Access Journals (Sweden)

    Ecaterina Fodor

    2011-06-01

    Full Text Available There is an increasing interest for important tree species conservation in the context of climate change, anthropogenic pressure and invasion of alien tree species. A key factor in the survival of trees is represented by the mycorrhizal association. The success of micropropagated trees also depends on the acquisition of mycorrhizal mutualists. Ectomycorrhizal roots samples from several Quercus species (Q. cerris, Q. frainetto, Q. robur were examined for mycorrhizal morphotypes’ characterization. The samples were collected during the vegetation season from stands located in Southern and North-Western Romania. 30 morphotypes of active mycorrhizae were identified with Cenococcum geophilumFr. (Ascomycota as dominating morphotype. Previous studies on somatic embryogenesis in Q. roburand Q. frainetto demonstrated the utility of in vitro techniques in obtaining plants from these recalcitrant seed producing species, considered at risk in various areas of the country, due to increasingly stressful conditions. The success rate of the acclimatization process depends on the mycorrhization performed either artificially, in the laboratory, either naturally, in the field. Ex situ mycorrhization solutions are considered as less costly, yet efficient alternative to improve the ex vitro survival of micropropagated plants or endangered tree species or for those with economic importance, in vitro propagation is an important conservation tool combined with the acquisition of appropriate mycorrhizal mutualists. 

  18. Mycorrhizal status of several Quercus species in Romania (Quercus cerris, Q. frainetto, Q. robur and the optimization perspective of growth conditions for in vitro propagated plants transplanted in the field

    Directory of Open Access Journals (Sweden)

    Ecaterina Fodor

    2011-02-01

    Full Text Available There is an increasing interest for important tree species conservation in the context of climate change, anthropogenic pressure and invasion of alien tree species. A key factor in the survival of trees is represented by the mycorrhizal association. The success of micropropagated trees also depends on the acquisition of mycorrhizal mutualists. Ectomycorrhizal roots samples from several Quercus species (Q. cerris, Q. frainetto, Q. robur were examined for mycorrhizal morphotypes’ characterization. The samples were collected during the vegetation season from stands located in Southern and North-Western Romania. 30 morphotypes of active mycorrhizaewere identified with Cenococcum geophilum Fr. (Ascomycota asdominating morphotype. Previous studies on somatic embryogenesis inQ. robur and Q. frainetto demonstrated the utility of in vitro techniques in obtaining plants from these recalcitrant seed producing species, considered at risk in various areas of the country, due to increasingly stressful conditions. The success rate of the acclimatization process depends on the mycorrhization performed either artificially, in the laboratory, either naturally, in the field. Ex situ mycorrhization solutions are considered as less costly, yet efficient alternative to improve the ex vitro survival ofmicropropagated plants or endangered tree species or for those with economic importance, in vitro propagation is an important conservation tool combined with the acquisition of appropriate mycorrhizal mutualists.

  19. Phytochemical and antifungal activities of Uvaria. chamae leaves and roots, Spondias mombin leaves and bark and Combretum racemosum leaves.

    Science.gov (United States)

    Okwuosa, O M T B; Chukwura, E I; Chukwuma, G O; Okwuosa, C N; Enweani, I B; Agbakoba, N R; Chukwuma, C M; Manafa, P O; Umedum, C U

    2012-12-01

    The effects of crude and dilutions of aqueous, methanolic and n-hexane extracts of Uvaria chamae (roots and leaves), Spondias mombin (leaves and bark) and Combretum racemosum (Leaves), on pathogenic candida albicans and aspergillus niger was studied. The aim was to contribute to the search for a cheaper, conventional cure for both fungi. Phytochemical analysis revealed varying degrees of alkaloids, glycosides, saponin, lipid and oil, tannins, flavonoids, terpenoids and acids. Agar diffusion method was used for anti fungal assay. Minimum inhibitory concentration (mic) used was 10 mg/ml of extract and dilutions of the non polar solvents of 10 (-1) and 10(-2) was used. Results showed that none of the plant parts was active against aspergillus niger. Combretum racemosum had no antifungal effect on tested organisms as well as the different dilutions. However crude methanolic extract of uvaria (roots and leaves), spondias ( bark and leaves ), and n-hexane extracts of uvaria (leaves and roots), produced anti candidal effects with diameters in this order 14.67 +/- 0.72mm, 10.67 +/- 0.52 mm, 11.00 +/- 0.47 mm, 15.00 +/- 0.47 mm, and 14.67 +/- 0.72 mm respectively. Some of the plant parts especially uvaria had zones of inhibition at a confidence limit comparable with control drug which is ketoconazole and it had inhibitory effects at a diameter of 20.06 +/- 0.40 mm.

  20. Radiocesium Contamination of Quercus Serrata From Fukushima Nuclear Power Plant Accident During 2011 and 2013

    Energy Technology Data Exchange (ETDEWEB)

    Ogawa, Hideki [Graduate School of Urban Environmental Science, Tokyo Metropolitan University, Minami-Osawa, Hachioji, Tokyo 192-0397 (Japan); Fukushima Prefectural Forestry Research Centre, Nishi-Shimasaka, Asaka, Koriyama, Fukushima 963-0112, Japan (Japan); Hirano, Yurika; Igei, Shigemitsu; Yokota, Kahori; Arai, Shio; Yoshida, Hirohisa [Graduate School of Urban Environmental Science, Tokyo Metropolitan University, Minami-Osawa, Hachioji, Tokyo 192-0397 (Japan); Itou, Hirohisa; Murakami, Kaori; Kumata, Atsushi [Fukushima Prefectural Forestry Research Centre, Nishi-Shimasaka, Asaka, Koriyama, Fukushima 963-0112, Japan (Japan)

    2014-07-01

    The objective of the study was to evaluate time dependence of contamination by radioactive cesium in the ecosystems at Yamakiya, Kawamata, Fukushima prefecture from 2011 to 2013. The depth contamination profile of soil and the three dimensional contamination profile of cedar tree were evaluated in the cedar forest at Yamakiya, the evacuation area, 30 km northwest from Fukushima Dai-ichi Nuclear Power Plant.The soil contamination proceeded in the depth direction within 4 7 months after the foul out, the depth concentration profiles was described linearly in logarithmic scale. The radiocesium in soil approached the depth of cedar roots within two years after the foul out. The contamination of outside of cedar tree, leaves twigs and bark in this area was in the range from 10,000 to 200,000 Bq/kgDW in August 2011. The inside contamination of cedar tree was in the rage from 500 to 10,000 Bq/kgDW, and the inside concentration of radiocesium depended on the direction and the height. The first stage of inside contamination of cedar tree was caused by the foliar and bark absorptions in 2011. The radiocesium existed particularly in heartwood and the phloem or the water vessel (sap wood) in cedar. The radiocesium concentration in heartwood depended on the height, however that in the phloem depended slightly on the height. The inside concentration of radiocesium in heartwood and sap wood closely related to the water content or distribution in wood. In this study, the relationship between transportation of water and radiocesium was discussed. (authors)

  1. 5 CFR 630.1111 - Limitation on the amount of donated annual leave received by an emergency leave recipient.

    Science.gov (United States)

    2010-01-01

    ... annual leave received by an emergency leave recipient. 630.1111 Section 630.1111 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS ABSENCE AND LEAVE Emergency Leave Transfer Program § 630.1111 Limitation on the amount of donated annual leave received by an emergency...

  2. Maternity leave, women's employment, and marital incompatibility.

    Science.gov (United States)

    Hyde, J S; Essex, M J; Clark, R; Klein, M H

    2001-09-01

    This research investigated the relationship between the length of women's maternity leave and marital incompatibility, in the context of other variables including the woman's employment, her dissatisfaction with the division of household labor, and her sense of role overload. Length of leave, work hours, and family salience were associated with several forms of dissatisfaction, which in turn predicted role overload. Role overload predicted increased marital incompatibility for experienced mothers but did not for first-time mothers, for whom discrepancies between preferred and actual child care were more important. Length of maternity leave showed significant interactions with other variables, supporting the hypothesis that a short leave is a risk factor that, when combined with another risk factor, contributes to personal and marital distress.

  3. Pharmacognostical profile of Paederia foetida Linn. leaves

    National Research Council Canada - National Science Library

    Shetti, Sandeep; Chellappan, Dinesh Kumar; Sharma, Indra Prakash; Kalusalingam, Anandarajagopal

    2012-01-01

    The leaves of Paederia foetida Linn. (P. foetida) are commonly known as skunk vine or Chinese fever vine, are used for various ailments medicinally throughout Asia and other tropical parts of the world by traditional healers...

  4. Occupational exposures and sick leave during pregnancy

    DEFF Research Database (Denmark)

    Hansen, Mette Lausten; Thulstrup, Ane Marie; Juhl, Mette

    2015-01-01

    OBJECTIVE: This study aimed to investigate associations between work postures, lifting at work, shift work, work hours, and job strain and the risk of sick leave during pregnancy from 10-29 completed pregnancy weeks in a large cohort of Danish pregnant women. METHODS: Data from 51 874 pregnancies...... episode of sick leave as the primary outcome. RESULTS: We found statistically significant associations between all the predictors and risk of sick leave; for non-sitting work postures (HRrange 1.55-2.79), cumulative lifting HRtrend 1.29, 95% CI 1.26-1.31, shift work (HRevening 1.90, 95% CI 1...... previous findings and suggest that initiatives to prevent sick leave during pregnancy could be based on work conditions. Preventive measures may have important implications for pregnant women and workplaces....

  5. Early School Leaving: Reasons and Consequences

    Directory of Open Access Journals (Sweden)

    Erika GYÖNÖS

    2011-11-01

    Full Text Available Early school leaving represents a loss of potential that has effects on both social and economic scale (reduced social cohesion, lower financial incomes, increase of social allocations. Early school leaving has various reasons that can be either social or economic. Due to the average statistics of the 27 countries of the European Union, in 2008 78,5% of the populations of these countries went to school regularly, whereas the same statistics applied for Romania showed an extent of 78,3%. The statistics of early school leaving showed some 14, 9% in the countries of the EU, whereas in Romania this index was higher (15, 9%. Sequel to some analyses we can state that there is a strong relationship between the variables named participation in education and early school leaving; more than that, there is a strong relationship between the extent of school studies completion and the rate of unemployment.

  6. The Chromatography of Leaves and Inks.

    Science.gov (United States)

    Chemecology, 1997

    1997-01-01

    Describes the use of a simple process known as chromatography to separate and observe the color pigments in leaves, inks, and other materials. Provides some historical background and detailed procedures. (DDR)

  7. Auxin level and regeneration of Begonia leaves.

    Science.gov (United States)

    Heide, O M

    1968-06-01

    As previously found, both the level of ether-extractable auxin (presumably indole-3-acetic acid) and the root-forming ability of B.xcheimantha leaves are increased under long-day conditions by high temperature, whereas the capacity for adventitious bud formation is reduced. However, this relation is present under relatively high light intensity only. Under the low light intensities in late fall neither auxin level nor regeneration ability were significantly affected by temperature.Dark treatment of detached leaves for 2 to 16 days greatly counteracted the inhibitory effect of high temperature on bud formation and reduced both the auxin level and the root-forming ability of the leaves.The great seasonal changes in the regeneration ability of Begonia leaves seem to be the result of a complex interaction of temperature, day-length, and daily light energy on the level of endogenous auxin and other growth regulators.

  8. Anthelmintic activity of leaves of justicia beddomei.

    Science.gov (United States)

    Srinivasa, U; Rao, J Venkateshwara; Krupanidhi, A M; Shanmukhappa, S

    2007-01-01

    Ethanolic and Chloroform extract of leaves of Justicia beddomei were evaluated separately for anthelmintic activity on adult Indian earthworms Pheretima posthuma, using Piperazine citrate as reference standard. The results indicated that ethanolic extract was more potent than the chloroform extract.

  9. Fathers on Parental Leave in Denmark

    DEFF Research Database (Denmark)

    Reinicke, Kenneth; Cybulski, Franz Wilhelm; Drews, Lea Vedel

    2005-01-01

    In the article it is argued that contemporary fatherhood and masculinity differ increasingly from hegemonic masculinity according to which men are primarily responsible for ensuring the financial basis of the family. The article “Fathers on Parental Leave in Denmark”, based on interviews with 15......, parental leave and domestic affairs. The article also demonstrates that the issue of parental leave may cause a conflict of interest between an employer and en employee although the majority of employers in this study emphasize that parental leave is unproblematic for them....... Danish men and 8 employers, shows that many men’s ideas about fatherhood and family responsibility tend to revolve around such aspects as close contact and involvement with children. However, it seems that men do not acknowledge fully the significance of gender for their decisions concerning the child...

  10. Holocene variability in the range distribution and abundance of Pinus, Picea abies, and Quercus in Romania; implications for their current status

    Science.gov (United States)

    Feurdean, Angelica; Tanţău, Ioan; Fărcaş, Sorina

    2011-10-01

    This paper examines fourteen fossil pollen datasets from Romania. It aims to investigate the temporal and spatial variability in the range distribution and abundance of three forest taxa, Pinus, Picea abies, and Quercus, during the Holocene. This is essential for understanding their current status in the forests of Eastern Europe, the conditions under which they arose, and the timing and processes responsible for their variability. Results from this synthesis do not indicate any apparent time lag in the establishment of Pinus diploxylon type ( Pinus sylvestris and Pinus mugo), Pinus cembra, P. abies, and Quercus across Romania within the limits of the dating resolution. However, the onset of the mass expansion of P. abies was not uniform, spreading earlier from sites in the western and north-western Carpathians (11,000-10,500 yr BP) than in the east (10,000 yr BP). We found that sites from the western, north-western, and northern Carpathians contained higher abundances of P. abies, whilst Quercus was in higher abundances in sites from the east, but there was no regional distinctiveness in the abundance of Pinus across the study area. However, P. diploxylon type was found in much higher abundance than P. cembra. Additionally, results indicate a greater proportion of Pinus (mainly P. diplxylon type) at high elevations, P. abies at mid to high elevations, and Quercus at low elevations (Pinus in the early Holocene boreal forest is likely the legacy of its local glacial refugia, fast life history strategies, high stress tolerance, and large habitat availability. In contrast, Pinus exhibited poor competitive abilities and was quickly replaced with P. abies and temperate deciduous taxa after 10,500 yr BP. P. abies has persisted in large abundances at higher elevations (above 1000 m) until the present day, as a result of good competitive abilities, and resilience to climate change and disturbance. The long-term dominance of P. abies appears to have been spatially

  11. Anticancer activity of Morus nigra leaves extract

    OpenAIRE

    Muhammad Imran Qadir; Muhammad Ali; Zubair Ibrahim

    2014-01-01

    Plants are screened for treatment of many ailments including cancer because they possess certain potential constituents which are effective for treatment. The aim of this study was to evaluate the anticancer activity of Morus nigra leaves against human cervical cancer cell line (HeLa). n-Hexane and aqueous methanolic extract of plant’s leaves were made by maceration. Anticancer activity was estimated by methyl-thiazolyl-tetrazolium (MTT) assay and percentage inhibition of cells was calculated...

  12. Fathers' Leave, Fathers' Involvement and Child Development

    DEFF Research Database (Denmark)

    del Carmen Huerta, Maria; Lausten, Mette; Baxter, Jennifer

    their involvement translates into positive child cognitive and behavioural outcomes. This analysis shows that fathers’ leave, father’s involvement and child development are related. Fathers who take leave, especially those taking two weeks or more, are more likely to carry out childcare related activities when...... was available, results suggest that the kind of involvement matters. These results suggest that what matters is the quality and not the quantity of father-child interactions....

  13. Sweets for the foe - effects of nonstructural carbohydrates on the susceptibility of Quercus robur against Phytophthora quercina.

    Science.gov (United States)

    Angay, Oguzhan; Fleischmann, Frank; Recht, Sabine; Herrmann, Sylvie; Matyssek, Rainer; Oßwald, Wolfgang; Buscot, François; Grams, Thorsten E E

    2014-09-01

    The root-rot pathogen Phytophthora quercina is a key determinant of oak decline in Europe. The susceptibility of pedunculate oak (Quercus robur) to this pathogen has been hypothesized to depend on the carbon availability in roots as an essential resource for defense. Microcuttings of Q. robur undergo an alternating rhythm of root and shoot growth. Inoculation of mycorrhizal (Piloderma croceum) and nonmycorrhizal oak roots with P. quercina was performed during both growth phases, that is, root flush (RF) and shoot flush (SF). Photosynthetic and morphological responses as well as concentrations of nonstructural carbohydrates (NSC) were analyzed. Infection success was quantified by the presence of pathogen DNA in roots. Concentrations of NSC in roots depended on the alternating root/shoot growth rhythm, being high and low during RF and SF, respectively. Infection success was high during RF and low during SF, resulting in a significantly positive correlation between pathogen DNA and NSC concentration in roots, contrary to the hypothesis. The alternating growth of roots and shoots plays a crucial role for the susceptibility of lateral roots to the pathogen. NSC availability in oak roots has to be considered as a benchmark for susceptibility rather than resistance against P. quercina.

  14. Atmospheric pollutants in peri-urban forests of Quercus ilex: evidence of pollution abatement and threats for vegetation.

    Science.gov (United States)

    García-Gómez, Héctor; Aguillaume, Laura; Izquieta-Rojano, Sheila; Valiño, Fernando; Àvila, Anna; Elustondo, David; Santamaría, Jesús M; Alastuey, Andrés; Calvete-Sogo, Héctor; González-Fernández, Ignacio; Alonso, Rocío

    2016-04-01

    Peri-urban vegetation is generally accepted as a significant remover of atmospheric pollutants, but it could also be threatened by these compounds, with origin in both urban and non-urban areas. To characterize the seasonal and geographical variation of pollutant concentrations and to improve the empirical understanding of the influence of Mediterranean broadleaf evergreen forests on air quality, four forests of Quercus ilex (three peri-urban and one remote) were monitored in different areas in Spain. Concentrations of nitrogen dioxide (NO2), ammonia (NH3), nitric acid (HNO3) and ozone (O3) were measured during 2 years in open areas and inside the forests and aerosols (PM10) were monitored in open areas during 1 year. Ozone was the only air pollutant expected to have direct phytotoxic effects on vegetation according to current thresholds for the protection of vegetation. The concentrations of N compounds were not high enough to directly affect vegetation but could be contributing through atmospheric N deposition to the eutrophization of these ecosystems. Peri-urban forests of Q. ilex showed a significant below-canopy reduction of gaseous concentrations (particularly NH3, with a mean reduction of 29-38%), which indicated the feasibility of these forests to provide an ecosystem service of air quality improvement. Well-designed monitoring programs are needed to further investigate air quality improvement by peri-urban ecosystems while assessing the threat that air pollution can pose to vegetation.

  15. 麻栎种子萌发的抑制机制%Inhibitory Mechanism of Seed Germination of Quercus acutissima

    Institute of Scientific and Technical Information of China (English)

    刘艳; 李庆梅; 刘广全; 刘勇; 侯龙鱼; 李国雷

    2012-01-01

    Over the last three decades, decline of oak (Quercus acutissima) natural regeneration has drawn wide attention. Exploration of the causes and development of the seedling technology, which promotes quick and uniform germination of oak seeds, arise interesting of forest researchers. In this paper, the seed cold storage and mechanical damage treatments were studied on germination of Q. acutissima. Methanol extracts of embryo, cotyledon and pericarp of oak seeds were used to investigate existence of inhibitory substance by testing germination of Brassica campestris seeds that were cultivated in Sanyo growth cabinet. The results showed that: (1) removing scar, pericarp, or cutting off a small piece of basal cotyledon increased the rooting rate and percentage, however, cutting off more than 1 /2 cotyledon had negative effects; (2) the seed cold storage accelerated the germination; ( 3 ) Germination rates of B. campestris seeds treated by methanol extracts from embryo of Q. acutissima seeds were significantly lower than control, and inhibitors from embryo, cotyledon and pericarp played a negative role in growth of root and shoot of B. campestris seedlings, indicating that the inhibitors of oak seeds might mainly restrict growth of root and shoot themselves, and be responsible for germinating irregularly. The results have guiding significance for directly seeding afforestation and seedling of Q. acutissima.

  16. [Spatial pattern analysis and associations of Quercus aquifolioides population at different growth stages in Southeast Tibet, China].

    Science.gov (United States)

    Shen, Zhi-qiang; Hua, Min; Dan, Qu; Lu, Jie; Fang, Jiang-ping

    2016-02-01

    This article analyzed the spatial pattern and its correlation of Quercus aquifolioides, Southeast Tibet at different growing stages by using Ripley' s L function in the method of point pattern, analysis. The results showed the diameter structure of Q. aquifolioides population in Southeast Tibet followed a 'single peak' shape and the saplings and medium trees predominated in number in the whole population. The population had a high regeneration rate and was of increase type. In the growth process of Q. aquifolioides from saplings to large trees, saplings and medium trees showed aggregation distribution at.small scale, while large trees showed basically random distribution at whole scale. There was significant correlation between saplings with medium or large trees at small scale, however, there was no correlation between medium and large trees. In the growth process of Q. aquifolioides population from saplings, medium trees to large trees, its spatial pattern developed from aggregative distribution to random distribution. The natural regeneration of Q. aquifolioides population was affected not only by interspecific competition, but also by intraspecific competition. In the similar natural environment, the most important factors affecting the spatial pattern of Q. aquifoioides population were its own biological and ecological characteristics.

  17. Comparative Drought Responses of Quercus ilex L. and Pinus sylvestris L. in a Montane Forest Undergoing a Vegetation Shift

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    David Aguadé

    2015-07-01

    Full Text Available Different functional and structural strategies to cope with water shortage exist both within and across plant communities. The current trend towards increasing drought in many regions could drive some species to their physiological limits of drought tolerance, potentially leading to mortality episodes and vegetation shifts. In this paper, we study the drought responses of Quercus ilex and Pinus sylvestris in a montane Mediterranean forest where the former species is replacing the latter in association with recent episodes of drought-induced mortality. Our aim was to compare the physiological responses to variations in soil water content (SWC and vapor pressure deficit (VPD of the two species when living together in a mixed stand or separately in pure stands, where the canopies of both species are completely exposed to high radiation and VPD. P. sylvestris showed typical isohydric behavior, with greater losses of stomatal conductance with declining SWC and greater reductions of stored non-structural carbohydrates during drought, consistent with carbon starvation being an important factor in the mortality of this species. On the other hand, Q. ilex trees showed a more anisohydric behavior, experiencing more negative water potentials and higher levels of xylem embolism under extreme drought, presumably putting them at higher risk of hydraulic failure. In addition, our results show relatively small changes in the physiological responses of Q. ilex in mixed vs. pure stands, suggesting that the current replacement of P. sylvestris by Q. ilex will continue.

  18. ADSORPTION CHARACTERIZATION OF CO(II IONS ONTO CHEMICALLY TREATED QUERCUS COCCIFERA SHELL: EQUILIBRIUM, KINETIC AND THERMODYNAMIC STUDIES

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    M. Hamdi Karaoglu

    2011-04-01

    Full Text Available Quercus coccifera shell (QCS, a relatively abundant and inexpensive material, is currently being investigated as an adsorbent to remove cobalt(II from water. Before the adsorption experiments, QCS was subjected to chemical treatment to provide maximum surface area. Then, the kinetics and adsorption mechanism of Co(II ions on QCS were studied using different parameters such as adsorbent dosage, initial concentration, temperature, contact time, and solution pH. The loaded metals could be desorbed effectively with dilute hydrochloric acid, nitric acid, and 0.1 M EDTA. The Langmuir and Freundlich models were used to describe the uptake of cobalt on QCS. The equilibrium adsorption data were better fitted to Langmuir adsorption isotherm model. The maximum adsorption capacity (qm of QCS for Co(II was 33 mg g-1. Various kinetic models were used to describe the adsorption process. The adsorption followed pseudo second-order kinetic model. The intraparticle diffusion was found to be the rate-limiting step in the adsorption process. The diffusion coefficients were calculated and found to be in the range of 3.11×10−6 to 168.78×10−6 cm2s-1. The negative DH* value indicated exothermic nature of the adsorption.

  19. Effect of elevated atmospheric CO2 concentration on growth and leaf litter decomposition of Quercus acutissima and Fraxinus rhynchophylla.

    Science.gov (United States)

    Cha, Sangsub; Chae, Hee-Myung; Lee, Sang-Hoon; Shim, Jae-Kuk

    2017-01-01

    The atmospheric carbon dioxide (CO2) level is expected to increase substantially, which may change the global climate and carbon dynamics in ecosystems. We examined the effects of an elevated atmospheric CO2 level on the growth of Quercus acutissima and Fraxinus rhynchophylla seedlings. We investigated changes in the chemical composition of leaf litter, as well as litter decomposition. Q. acutissima and F. rhynchophylla did not show differences in dry weight between ambient CO2 and enriched CO2 treatments, but they exhibited different patterns of carbon allocation, namely, lower shoot/root ratio (S/R) and decreased specific leaf area (SLA) under CO2-enriched conditions. The elevated CO2 concentration significantly reduced the nitrogen concentration in leaf litter while increasing lignin concentrations and carbon/nitrogen (C/N) and lignin/N ratios. The microbial biomass associated with decomposing Q. acutissima leaf litter was suppressed in CO2 enrichment chambers, while that of F. rhynchophylla was not. The leaf litter of Q. acutissima from the CO2-enriched chambers, in contrast with F. rhynchophylla, contained much lower nutrient concentrations than that of the litter in the ambient air chambers. Consequently, poorer litter quality suppressed decomposition.

  20. Responses of nutrients and mobile carbohydrates in Quercus variabilis seedlings to environmental variations using in situ and ex situ experiments.

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    Jing-Pin Lei

    Full Text Available Forest tree species distributed across a wide range of geographical areas are subjected to differential climatic and edaphic conditions and long-term selection, leading to genotypes with morphological and physiological adaptation to the local environment. To test the ability of species to cope with changing environmental conditions, we studied the ecophysiological features of Quercus variabilis using seedlings grown in geographically widely isolated populations (Exp. I, in situ and in a common garden (Exp. II, ex situ using seedlings originating from those populations. We found that Q. variabilis plants grown in different locations along a south-north gradient had different levels of nutrients (N, P, K and carbon-physiological performance (photosynthesis, non-structural carbohydrates, such as soluble sugars and starch, and that these physiological differences were not correlated with local soil properties. These geographic variations of plant physiology disappeared when plants from different locations were grown in the same environment. Our results indicate that the physiological performance of Q. variabilis plants is mainly determined by the climatic variations across latitude rather than by their soils or by genetic differentiation. The adaptive ability of Q. variabilis found in the present study suggests that this species has the potential to cope, at least to some extent, with changing environmental conditions.