WorldWideScience

Sample records for maple seedlings affected

  1. Influence of ozone on cold acclimation in sugar maple seedlings

    Energy Technology Data Exchange (ETDEWEB)

    Bertrand, A. [Agriculture and Agri-Food Canada, Sainte-Foy, PQ (Canada) Research Station; Robitaille, G. [Natural Resources Canada, Ste. Foy, PQ (Canada) Canadian Forest Service; Nadeau, P.; Castonguay, Y. [Agriculture and Agri-Food Canada, Sainte-Foy, PQ (Canada) Research Station

    1999-07-01

    A study was carried out with the aim of determining: a) if exposure to ozone gas induces changes in the key parts of cold acclimation in maple seedlings; and b) if the putative changes effect the process of cold acclimation. Two year old seedlings were exposed to two concentrations of ozone, ambient ozone (low ozone), and threefold ambient ozone concentrations (high ozone) from June to September. During the fall, winter and spring, the seedlings were left outdoors to acclimate to natural winter conditions. The freezing tolerance of stems and root tissues was determined for high ozone and low ozone treated seedlings over the winter period. Concomitant determination of the concentrations of starch, sucrose, raffinose, and stachyose in the sugar maple roots as well as ABA concentration in the xylem sap were carried out to assess the molecular changes associated with the cold acclimation of seedlings in the two treatments. Exposure to high concentrations of ozone did not decrease the freezing tolerance of sugar maple roots and improved the freezing tolerance of the stems in the fall. During the period of cold acclimation, an eightfold increase in sucrose concentration occurred in roots and stems, while starch concentration decreased. In roots, the accumulation of soluble sugars coincided with the period of lowest soil temperature. This showed that temperature has a major influence on the amount of sugar formed and the degree of freezing tolerance. There were no ozone treatment effects on either starch hydrolysis or sucrose accumulation in roots. Sucrose is a membrane and protein stabilizer during winter drying. In roots, the concentrations of the galactose containing oligosaccharides, raffinose and stachyose, were higher in the high ozone treatment than in the low ozone treatment, and stachyose indicated a similar response in stems. There is a relation between the increase in ABA concentration and cold acclimation in the sugar maple. 29 refs., 7 figs.

  2. Competition for nitrogen sources between European beech (Fagus sylvatica) and sycamore maple (Acer pseudoplatanus) seedlings.

    Science.gov (United States)

    Simon, J; Waldhecker, P; Brüggemann, N; Rennenberg, H

    2010-05-01

    To investigate the short-term consequences of direct competition between beech and sycamore maple on root N uptake and N composition, mycorrhizal seedlings of both tree species were incubated for 4 days (i.e. beech only, sycamore maple only or both together) in an artificial nutrient solution with low N availability. On the fourth day, N uptake experiments were conducted to study the effects of competition on inorganic and organic N uptake. For this purpose, multiple N sources were applied with a single label. Furthermore, fine roots were sampled and analysed for total amino acids, soluble protein, total nitrogen, nitrate and ammonium content. Our results clearly show that both tree species were able to use inorganic and organic N sources. Uptake of inorganic and organic N by beech roots was negatively affected in the presence of the competing tree species. In contrast, the presence of beech stimulated inorganic N uptake by sycamore maple roots. Both the negative effect of sycamore maple on N uptake of beech and the positive effect of beech on N uptake of sycamore maple led to an increase in root soluble protein in beech, despite an overall decrease in total N concentration. Thus, beech compensated for the negative effects of the tree competitor on N uptake by incorporating less N into structural N components, but otherwise exhibited the same strategy as the competitor, namely, enhancing soluble protein levels in roots when grown under competition. It is speculated that enhanced enzyme activities of so far unknown nature are required in beech as a defence response to inter-specific competition.

  3. Sugar maple seedling anatomy and element localization at forest sites with differing nutrient levels

    Science.gov (United States)

    Carolyn J. McQuattie; Robert P. Long; Thomas J. Hall

    1999-01-01

    Sugar maple (Acer saccharum Marsh.) seedlings often have poor survival on acidic unglaciated portions of the Allegheny Plateau. Greater survival is found after lime treatment of unglaciated sites or on glaciated areas of the Plateau. The difference in survival rate may depend in part on the acidity or chemical composition of the soil.

  4. The changes in leaf reflectance of sugar maple (Acer saccharum Marsh) seedlings in response to heavy metal stress

    Science.gov (United States)

    Schwaller, M. R.; Schnetzler, C. C.; Marshall, P. E.

    1983-01-01

    The effects of heavy metal stress on leaf reflectance of sugar maple seedlings (Acer saccharum Marsh) are examined. It is found that sugar maple seedlings treated with anomalous amounts of heavy metals in the rooting medium exhibited an increased leaf reflectance over the entire range of investigated wavelengths, from 475 to 1650 nm. These results conform to those of a previous investigation in the wavelengths from 475 to 660 nm, but tend to contradict the previous study in the near infrared wavelengths from 1000 to 1650 nm. The differences may possibly be due to different water regimes in the two investigations. Previously announced in STAR as N81-29729

  5. The changes in leaf reflectance of sugar maple seedlings (Acer saccharum Marsh) in response to heavy metal stress

    Science.gov (United States)

    Schwaller, M. R.; Schnetzler, C. C.; Marshall, P. E.

    1981-01-01

    The effects of heavy metal stress on leaf reflectance of sugar maple seedlings (Acer saccharum Marsh) are examined. It is found that sugar maple seedlings treated with anomalous amounts of heavy metals in the rooting medium exhibited an increased leaf reflectance over the entire range of investigated wavelengths, from 475 to 1650 nm. These results conform to those of a previous investigation in the wavelengths from 475 to 660nm, but tend to contradict the previous study in the near infrared wavelengths from 1000 to 1650nm. The differences may possible be due to different water regimes in the two investigations.

  6. Effects of elevated [CO2] and low soil moisture on the physiological responses of Mountain Maple (Acer spicatum L. seedlings to light.

    Directory of Open Access Journals (Sweden)

    Gabriel Danyagri

    Full Text Available Global climate change is expected to affect how plants respond to their physical and biological environments. In this study, we examined the effects of elevated CO2 ([CO2] and low soil moisture on the physiological responses of mountain maple (Acer spicatum L. seedlings to light availability. The seedlings were grown at ambient (392 µmol mol(-1 and elevated (784 µmol mol(-1 [CO2], low and high soil moisture (M regimes, at high light (100% and low light (30% in the greenhouse for one growing season. We measured net photosynthesis (A, stomatal conductance (g s, instantaneous water use efficiency (IWUE, maximum rate of carboxylation (V cmax, rate of photosynthetic electron transport (J, triose phosphate utilization (TPU, leaf respiration (R d, light compensation point (LCP and mid-day shoot water potential (Ψx. A and g s did not show significant responses to light treatment in seedlings grown at low soil moisture treatment, but the high light significantly decreased the C i/C a in those seedlings. IWUE was significantly higher in the elevated compared with the ambient [CO2], and the effect was greater at high than the low light treatment. LCP did not respond to the soil moisture treatments when seedlings were grown in high light under both [CO2]. The low soil moisture significantly reduced Ψx but had no significant effect on the responses of other physiological traits to light or [CO2]. These results suggest that as the atmospheric [CO2] rises, the physiological performance of mountain maple seedlings in high light environments may be enhanced, particularly when soil moisture conditions are favourable.

  7. Effects of elevated [CO2] and low soil moisture on the physiological responses of Mountain Maple (Acer spicatum L.) seedlings to light.

    Science.gov (United States)

    Danyagri, Gabriel; Dang, Qing-Lai

    2013-01-01

    Global climate change is expected to affect how plants respond to their physical and biological environments. In this study, we examined the effects of elevated CO2 ([CO2]) and low soil moisture on the physiological responses of mountain maple (Acer spicatum L.) seedlings to light availability. The seedlings were grown at ambient (392 µmol mol(-1)) and elevated (784 µmol mol(-1)) [CO2], low and high soil moisture (M) regimes, at high light (100%) and low light (30%) in the greenhouse for one growing season. We measured net photosynthesis (A), stomatal conductance (g s), instantaneous water use efficiency (IWUE), maximum rate of carboxylation (V cmax), rate of photosynthetic electron transport (J), triose phosphate utilization (TPU)), leaf respiration (R d), light compensation point (LCP) and mid-day shoot water potential (Ψx). A and g s did not show significant responses to light treatment in seedlings grown at low soil moisture treatment, but the high light significantly decreased the C i/C a in those seedlings. IWUE was significantly higher in the elevated compared with the ambient [CO2], and the effect was greater at high than the low light treatment. LCP did not respond to the soil moisture treatments when seedlings were grown in high light under both [CO2]. The low soil moisture significantly reduced Ψx but had no significant effect on the responses of other physiological traits to light or [CO2]. These results suggest that as the atmospheric [CO2] rises, the physiological performance of mountain maple seedlings in high light environments may be enhanced, particularly when soil moisture conditions are favourable.

  8. 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...

  9. Photosynthetic and growth response of sugar maple (Acer saccharum Marsh.) mature trees and seedlings to calcium, magnesium, and nitrogen additions in the Catskill Mountains, NY, USA

    Science.gov (United States)

    Momen, Bahram; Behling, Shawna J; Lawrence, Gregory B.; Sullivan, Joseph H

    2015-01-01

    Decline of sugar maple in North American forests has been attributed to changes in soil calcium (Ca) and nitrogen (N) by acidic precipitation. Although N is an essential and usually a limiting factor in forests, atmospheric N deposition may cause N-saturation leading to loss of soil Ca. Such changes can affect carbon gain and growth of sugar maple trees and seedlings. We applied a 22 factorial arrangement of N and dolomitic limestone containing Ca and Magnesium (Mg) to 12 forest plots in the Catskill Mountain region of NY, USA. To quantify the short-term effects, we measured photosynthetic-light responses of sugar maple mature trees and seedlings two or three times during two summers. We estimated maximum net photosynthesis (An-max) and its related light intensity (PAR at An-max), apparent quantum efficiency (Aqe), and light compensation point (LCP). To quantify the long-term effects, we measured basal area of living mature trees before and 4 and 8 years after treatment applications. Soil and foliar chemistry variables were also measured. Dolomitic limestone increased Ca, Mg, and pH in the soil Oe horizon. Mg was increased in the B horizon when comparing the plots receiving N with those receiving CaMg. In mature trees, foliar Ca and Mg concentrations were higher in the CaMg and N+CaMg plots than in the reference or N plots; foliar Ca concentration was higher in the N+CaMg plots compared with the CaMg plots, foliar Mg was higher in the CaMg plots than the N+CaMg plots; An-max was maximized due to N+CaMg treatment; Aqe decreased by N addition; and PAR at An-max increased by N or CaMg treatments alone, but the increase was maximized by their combination. No treatment effect was detected on basal areas of living mature trees four or eight years after treatment applications. In seedlings, An-max was increased by N+CaMg addition. The reference plots had an open herbaceous layer, but the plots receiving N had a dense monoculture of common woodfern in the

  10. Photosynthetic and Growth Response of Sugar Maple (Acer saccharum Marsh. Mature Trees and Seedlings to Calcium, Magnesium, and Nitrogen Additions in the Catskill Mountains, NY, USA.

    Directory of Open Access Journals (Sweden)

    Bahram Momen

    Full Text Available Decline of sugar maple in North American forests has been attributed to changes in soil calcium (Ca and nitrogen (N by acidic precipitation. Although N is an essential and usually a limiting factor in forests, atmospheric N deposition may cause N-saturation leading to loss of soil Ca. Such changes can affect carbon gain and growth of sugar maple trees and seedlings. We applied a 22 factorial arrangement of N and dolomitic limestone containing Ca and Magnesium (Mg to 12 forest plots in the Catskill Mountain region of NY, USA. To quantify the short-term effects, we measured photosynthetic-light responses of sugar maple mature trees and seedlings two or three times during two summers. We estimated maximum net photosynthesis (An-max and its related light intensity (PAR at An-max, apparent quantum efficiency (Aqe, and light compensation point (LCP. To quantify the long-term effects, we measured basal area of living mature trees before and 4 and 8 years after treatment applications. Soil and foliar chemistry variables were also measured. Dolomitic limestone increased Ca, Mg, and pH in the soil Oe horizon. Mg was increased in the B horizon when comparing the plots receiving N with those receiving CaMg. In mature trees, foliar Ca and Mg concentrations were higher in the CaMg and N+CaMg plots than in the reference or N plots; foliar Ca concentration was higher in the N+CaMg plots compared with the CaMg plots, foliar Mg was higher in the CaMg plots than the N+CaMg plots; An-max was maximized due to N+CaMg treatment; Aqe decreased by N addition; and PAR at An-max increased by N or CaMg treatments alone, but the increase was maximized by their combination. No treatment effect was detected on basal areas of living mature trees four or eight years after treatment applications. In seedlings, An-max was increased by N+CaMg addition. The reference plots had an open herbaceous layer, but the plots receiving N had a dense monoculture of common woodfern in the

  11. The effect of microbial inocula on the growth of black locust, Siberian elm and silver maple seedlings

    Directory of Open Access Journals (Sweden)

    Hajnal-Jafari Timea

    2014-01-01

    Full Text Available Growth and development of forest plants depend mostly on the soil microbial activity since no mineral or organic fertilizers are applied. Microbial processes can be activated and conditions for plants development improved with the introduction of selected microorganisms in the soil. With the aim of obtaining quality planting material in a shorter period of time, the effects of Azotobacter chroococcum and Streptomyces sp. on the early growth of black locust (Robinia pseudoacacia, Siberian elm (Ulmus pumila and silver-leaf maple (Acer dasycarpum were investigated in this study. Microorganisms were applied individually and in a mixture (1:1. Plant height was measured on the 90th, 120th and 180th day after planting. Plant diameter, as well as the number of actinomycetes and azotobacters was measured at the end of the vegetation period (180 days after planting. Applied microorganisms had a positive effect on the seedling height in all three plant species, with the best effect found in the black locust. Effectiveness of applied microorganisms on seedling diameter was the highest in the silver-leaf maple. The largest number of azotobacters was found in the rhizosphere of black locust. Number of microorganisms from both groups was increased in the inoculated variants. [Projekat Ministarstva nauke Republike Srbije, br. III 43002

  12. Responses of hybrid poplar clones and red maple seedlings to ambient O(3) under differing light within a mixed hardwood forest.

    Science.gov (United States)

    Wei, C; Skelly, J M; Pennypacker, S P; Ferdinand, J A; Savage, J E; Stevenson, R E; Davis, D D

    2004-07-01

    The responses of ramets of hybrid poplar (Populus spp.) (HP) clones NE388 and NE359, and seedlings of red maple (Acer rubrum, L.) to ambient ozone (O(3)) were studied during May-September of 2000 and 2001 under natural forest conditions and differing natural sunlight exposures (sun, partial shade and full shade). Ambient O(3) concentrations at the study site reached hourly peaks of 109 and 98 ppb in 2000 and 2001, respectively. Monthly 12-h average O(3) concentrations ranged from 32.3 to 52.9 ppb. Weekly 12-h average photosynthetically active radiation (PAR) within the sun, partial shade and full shade plots ranged from 200 to 750, 50 to 180, and 25 to 75 micromol m(-2) s(-1), respectively. Ambient O(3) exposure induced visible foliar symptoms on HP NE388 and NE359 in both growing seasons, with more severe injury observed on NE388 than on NE359. Slight foliar symptoms were observed on red maple seedlings during the 2001 growing season. Percentage of total leaf area affected (%LAA) was positively correlated with cumulative O(3) exposures. More severe foliar injury was observed on plants grown within the full shade and partial shade plots than those observed on plants grown within the sun plot. Lower light availability within the partial shade and full shade plots significantly decreased net photosynthetic rate (Pn) and stomatal conductance (g(wv)). The reductions in Pn were greater than reductions in g(wv), which resulted in greater O(3) uptake per unit Pn in plants grown within the partial shade and full shade plots. Greater O(3) uptake per unit Pn was consistently associated with more severe visible foliar injury in all species and/or clones regardless of differences in shade tolerance. These studies suggest that plant physiological responses to O(3) exposure are likely complicated due to multiple factors under natural forest conditions.

  13. Responses of secondary chemicals in sugar maple (Acer saccharum) seedlings to UV-B, springtime warming and nitrogen additions

    Energy Technology Data Exchange (ETDEWEB)

    Sager, E.P.S.; Hutchinson, T.C. [Trent Univ., Peterborough, ON (Canada). Environmental Studies

    2006-10-15

    Elevated UV-B radiation due to climatic change and ozone depletion may represent a significant springtime environmental stressor to germinating seedlings in temperate forest regions. This study aimed to determine the effects of UV-B, nitrogen (N) fertilization and climate warming on the concentrations of base cations and secondary metabolites in the foliage of sugar maple seedlings growing in acid or alkaline soils. The influence of measured flavonoids and phenolics on herbivore activity was examined, as well as the relationship between foliar concentrations of calcium (Ca); manganese (Mn); and N and the production of phenolic and flavonoid compounds. Experimental plots were established in mature hardwood forests in alkaline and acid soil locations in Bobcaygeon and Haliburton, Ontario. Pentagonal open-top chambers were used to lengthen the growing season and simulate an earlier spring. Ammonium nitrate was applied at a rate comparable with an additional deposition of 5 g N per m per year. Fertilizer was applied on 3 separate occasions. Ambient UV-B radiation was screened out with Mylar D polyester film. Sites, treatments and time of sampling had complex effects on foliar elemental chemistry, production of secondary compounds and herbivory. Foliar concentrations of individual phenols were higher in seedlings in the UV-B exclusion treatments. At both sites, removal of ambient UV-B led to increases in flavonoids and chlorogenic acid, and reduced herbivore activity. At Haliburton, ammonium nitrate fertilization led to further increases in foliar Mn. Nitrogen additions led to decreases in the concentrations of some flavonoids at both sites. It was concluded that the composition of the forest soil governs the response of seedlings when they are exposed to abiotic stressors. 63 refs., 5 tabs., 8 figs.

  14. The effects of UV-B, nitrogen fertilization, and springtime warming on sugar maple seedlings and the soil chemistry of two central Ontario forests

    Energy Technology Data Exchange (ETDEWEB)

    Sager, E.P.S.; Hutchinson, T.C. [Trent Univ., Peterborough, ON (Canada). Environmental Studies; Trent Univ., Peterborough, ON (Canada). Dept. of Resource Studies

    2005-10-01

    The carbon dioxide-driven increase in global temperature is a result of changes to the global carbon cycle resulting from deforestation, habitat destruction and increased emissions of gases from agriculture, combustion of fossil fuels, and industrial processes. In order to determine the likely ecosystem consequences of a warming climate, the potential interactions with other global stressors that currently coexist must be examined. To this end, this study assessed the simultaneous effects of UV-B, nitrogen fertilization, and climatic warming and their potential interactions on naturally growing sugar maple seedlings at two temperate sugar maple dominated hardwood forests growing on contrasting soil types. In particular, the study determined the effects of UV-B, nitrogen fertilization, and warming on surface soil chemistry as well as the effects of UV-B, nitrogen fertilization, climatic warming, and possible interactions on the total leaf cover, morphology, and foliar chemistry of sugar maple seedlings in treatment plots established at the Oliver and Haliburton field sites in Central Ontario. The 2 different sites were chosen in an effort to capture the increased sensitivity of Haliburton soils to increased nitrogen loadings. The foliar chemistry of maple seedlings reflected this difference, and additions of nitrogen led to elemental changes that appeared to be directly related to the underlying soils. The base-poor soils of Haliburton led to a reduced levels of calcium and magnesium in foliage and increased concentrations of aluminium and manganese compared with seedlings from Oliver. Nitrogen fertilization at Oliver led to increases in foliar magnesium, but did not mobilize the acid cations as was observed at Haliburton. The effect of nitrogen fertilization at Haliburton was also evident when coupled with open top chambers (OTCs) and UV-B. Since the treatment effects of OTCs were similar at both sites, it was suggested that changes in the elemental chemistry of

  15. Health of eastern North American sugar maple forests and factors affecting decline

    Science.gov (United States)

    Stephen B. Horsley; Robert P. Long; Scott W. Bailey; Richard A. Hallett; Philip M. Wargo

    2002-01-01

    Sugar maple (Acer saccharum) is a keystone species in the forests of the northeastern and Midwestern United States and eastern Canada. Its sustained health is an important issue in both managed and unmanaged forests. While sugar maple generally is healthy throughout its range, decline disease of sugar maple has occurred sporadically during the past...

  16. Nitrogen addition affects leaf nutrition and photosynthesis in sugar maple in a nutrient-poor northern Vermont forest

    Science.gov (United States)

    David S. Ellsworth

    1999-01-01

    Sugar maple-dominated forest ecosystems in the northeastern U.S. have been receiving precipitation nitrogen (N) inputs of 15 -20 kg N ha1 year1 since at least the mid 1980s sustained chronic N inputs of this magnitude into nutrient-poor forest ecosystems may cause eutrophication and affect ecosystem functioning as well as...

  17. Widespread sugar maple decline and regeneration failure in the Adirondacks

    Science.gov (United States)

    Jerry C. Jenkins; Elizabeth Moffett; Daphne Ross

    1999-01-01

    Over large areas of the Adirondacks, hardwood stands whose canopies are dominated by or contain abundant mature sugar maple (Acer saccharum Marsh.) have almost no sugar maple saplings or seedlings in the understory.

  18. Understanding Maple

    CERN Document Server

    Thompson, Ian

    2016-01-01

    Maple is a powerful symbolic computation system that is widely used in universities around the world. This short introduction gives readers an insight into the rules that control how the system works, and how to understand, fix, and avoid common problems. Topics covered include algebra, calculus, linear algebra, graphics, programming, and procedures. Each chapter contains numerous illustrative examples, using mathematics that does not extend beyond first-year undergraduate material. Maple worksheets containing these examples are available for download from the author's personal website. The book is suitable for new users, but where advanced topics are central to understanding Maple they are tackled head-on. Many concepts which are absent from introductory books and manuals are described in detail. With this book, students, teachers and researchers will gain a solid understanding of Maple and how to use it to solve complex mathematical problems in a simple and efficient way.

  19. Seedling quality of common sage (Salvia officinalis L. as affected by seedling production methods

    Directory of Open Access Journals (Sweden)

    Ömer Çalişkan

    2006-09-01

    Full Text Available The study was conducted to determine the effects of four different seedling production methods (i.e., open seedbed, greenhouse seedbed, float system and modified float system on the seedling growth and quality of common sage. Sowing rates were 1 g per m2 in an open seedbed and a greenhouse seedbed system, whereas the sowing rate was one seed per cell in the float and modified float systems. Emergence period, seedling growth period, the fresh and dry weights of aerial parts of seedlings, the fresh and dry weights of roots, seedling height, root height and stem diameter were determined as agronomical observations and measurements. The greenhouse seedling method was found to be superior over the other methods

  20. Analysis on Factors Affecting Seedling Establishment in Rice

    Directory of Open Access Journals (Sweden)

    Ju LUO

    2007-03-01

    Full Text Available Elongations of coleoptile and mesocotyl are related directly to rice seedling establishment in soil and height of plant is related to lodging in rice production. Twelve typical rice cultivars with different lengths of coleoptile and mesocotyl (long, medium and short were selected by screening the lengths of coleoptile and mesocotyl in 1500 accessions. The seedling establishments of these typical cultivars were compared under the combinations of different sowing depths and flooding durations, and two semi-dwarf varieties (G140, Zhong 96–21 with good seedling establishments and optimum mesocotyl lengths were found. The length of mesocotyl was completely fitted negative binomial distribution and the length of coleoptile was nearly fitted lognormal distribution. Analysis of the relationships among mesocotyl, coleoptile, seeding depth, flooding duration, and their interactions to seedling establishment percentage showed that there existed significant relations among mesocotyl, coleoptile, mesocotyl × coleoptile, seeding depth, flooding duration and mesocotyl × sowing depth in the experiment for seedling establishment.

  1. Analysis on Factors Affecting Seedling Establishment in Rice

    Institute of Scientific and Technical Information of China (English)

    LUO Ju; TANG Shao-qing; HU Pei-song; Aleman LOUIS; JIAO Gui-ai; TANG Jian

    2007-01-01

    Elongations of coleoptile and mesocotyl are related directly to rice seedling establishment in soil and height of plant is related to lodging in rice production. Twelve typical rice cultivars with different lengths of coleoptile and mesocotyl (long, medium and short) were selected by screening the lengths of coleoptile and mesocotyl in 1500 accessions. The seedling establishments of these typical cultivars were compared under the combinations of different sowing depths and flooding durations, and two semi-dwarf varieties (G140, Zhong 96-21) with good seedling establishments and optimum mesocotyl lengths were found. The length of mesocotyl was completely fitted negative binomial distribution and the length of coleoptile was nearly fitted Iognormal distribution.Analysis of the relationships among mesocotyl, coleoptile, seeding depth, flooding duration, and their interactions to seedling establishment percentage showed that there existed significant relations among mesocotyl, coleoptile, mesocotyl × coleoptile,seeding depth, flooding duration and mesocotyl × sowing depth in the experiment for seedling establishment.

  2. Growth of ponderosa pine seedlings as affected by air pollution

    Science.gov (United States)

    Momen, B.; Anderson, P. D.; Houpis, J. L. J.; Helms, J. A.

    The effect of air pollution on seedling survival and competitive ability is important to natural and artificial regeneration of forest trees. Although biochemical and physiological processes are sensitive indicators of pollution stress, the cumulative effects of air pollutants on seedling vigor and competitive ability may be assessed directly from whole-plant growth characteristics such as diameter, height, and photosynthetic area. A few studies that have examined intraspecific variation in seedling response to air pollution indicate that genotypic differences are important in assessing potential effects of air pollution on forest regeneration. Here, we studied the effects of acid rain (no-rain, pH 5.1 rain, pH 3.0 rain) and ozone (filtered, ambient, twice-ambient) in the field on height, diameter, volume, the height:diameter ratio, maximum needle length, and time to reach maximum needle length in seedlings of three families of ponderosa pine ( Pinus ponderosa Dougl. ex Laws). Seedling diameter, height, volume, and height:diameter ratio related significantly to their pre-treatment values. Twice-ambient ozone decreased seedling diameter compared with ozone-filtered air. A significant family-by-ozone interaction was detected for seedling height, as the height of only one of the three families was decreased by twice-ambient ozone compared with the ambient level. Seedling diameter was larger and the height:diameter ratio was smaller under pH 3.0 rain compared to either the no-rain or the pH 5.1-rain treatment. This suggests greater seedling vigor, perhaps due to a foliar fertilization effect of the pH 3.0 rain.

  3. Starch bioengineering affects cereal grain germination and seedling establishment

    DEFF Research Database (Denmark)

    Shaik, Shahnoor Sultana; Carciofi, Massimiliano; Martens, Helle Juel

    2014-01-01

    Cereal grain germination is central for plant early development, and efficient germination has a major role in crop propagation and malting. Endosperm starch is the prime energy reserve in germination and seedling establishment. In this study, it was hypothesized that optimized starch granule...

  4. Clinorotation affects mesophyll photosynthetic cells in leaves of pea seedlings.

    Science.gov (United States)

    Adamchuk, N I

    1998-07-01

    Experiments with autotrophs in altered gravity condition have a grate significant for development of space biology. The main results of investigation in the photosynthetic apparatus state under microgravity condition have based on the experiments with maturity plants and their differentiated cells. The structural and functional organization of photosynthetic cells in seedlings is poor understandable still. Along with chloroplasts preserving a native membrane system in palisade parenchyma cells of the 29-day pea plant leaves in microgravity, chloroplasts with fribly packed or damaged granae, whose thylakoids appeared as vesicles with an electrontransparent content, were also observed. The investigation of preceding process induced these effects have a sense. That is why, the goal of our experiments was to perform the study of a structural organization of the photosynthetic cells of 3-d pair of pea seedlings leaves under the influence of clinorotation.

  5. Starch bioengineering affects cereal grain germination and seedling establishment

    DEFF Research Database (Denmark)

    Shaik, Shahnoor Sultana; Carciofi, Massimiliano; Martens, Helle Juel;

    2014-01-01

    Cereal grain germination is central for plant early development, and efficient germination has a major role in crop propagation and malting. Endosperm starch is the prime energy reserve in germination and seedling establishment. In this study, it was hypothesized that optimized starch granule...... structure, and not only the endosperm starch content per se, is important for germination and seedling establishment. For that purpose, wild-type (WT), and specifically engineered degradable hyperphosphorylated (HP) starch and more resistant amylose-only (AO) starch barley lines were used. The transgenics...... showed no severe phenotypes and the WT and HP lines degraded the starch similarly, having 30% residual starch after 12 d of germination. However, the AO line showed significant resistance to degradation, having 57% residual starch. Interestingly, protein and β-glucan (BG) degradation was stimulated...

  6. Defoliation by pastoralists affects savanna tree seedling dynamics by limiting the facilitative role of canopy cover.

    Science.gov (United States)

    Bufford, Jennifer L; Gaoue, Orou G

    2015-07-01

    Recurrent tree defoliation by pastoralists, akin to herbivory, can negatively affect plant reproduction and population dynamics. However, our understanding of the indirect role of defoliation in seedling recruitment and tree-grass dynamics in tropical savanna is limited. In West African savanna, Fulani pastoralists frequently defoliate several fodder tree species to feed livestock in the dry season. We investigated the direct and indirect effects of recurrent defoliation of African mahogany (Khaya senegalensis) by Fulani people on seedling (forest systems in West Africa, it has the potential to affect tree-grass coexistence. Incorporating the influence of large tree defoliation into existing models of savanna dynamics can further our understanding of tree-grass coexistence and improve management. A rotating harvest system, which allows seedlings to recruit episodically, or a patchwork harvest, which maintains some nursery trees in the mosaic, could help sustain seedling recruitment and minimize the indirect effects of harvest.

  7. Norway maple displays greater seasonal growth and phenotypic plasticity to light than native sugar maple.

    Science.gov (United States)

    Paquette, Alain; Fontaine, Bastien; Berninger, Frank; Dubois, Karine; Lechowicz, Martin J; Messier, Christian; Posada, Juan M; Valladares, Fernando; Brisson, Jacques

    2012-11-01

    Norway maple (Acer platanoides L), which is among the most invasive tree species in forests of eastern North America, is associated with reduced regeneration of the related native species, sugar maple (Acer saccharum Marsh) and other native flora. To identify traits conferring an advantage to Norway maple, we grew both species through an entire growing season under simulated light regimes mimicking a closed forest understorey vs. a canopy disturbance (gap). Dynamic shade-houses providing a succession of high-intensity direct-light events between longer periods of low, diffuse light were used to simulate the light regimes. We assessed seedling height growth three times in the season, as well as stem diameter, maximum photosynthetic capacity, biomass allocation above- and below-ground, seasonal phenology and phenotypic plasticity. Given the north European provenance of Norway maple, we also investigated the possibility that its growth in North America might be increased by delayed fall senescence. We found that Norway maple had significantly greater photosynthetic capacity in both light regimes and grew larger in stem diameter than sugar maple. The differences in below- and above-ground biomass, stem diameter, height and maximum photosynthesis were especially important in the simulated gap where Norway maple continued extension growth during the late fall. In the gap regime sugar maple had a significantly higher root : shoot ratio that could confer an advantage in the deepest shade of closed understorey and under water stress or browsing pressure. Norway maple is especially invasive following canopy disturbance where the opposite (low root : shoot ratio) could confer a competitive advantage. Considering the effects of global change in extending the potential growing season, we anticipate that the invasiveness of Norway maple will increase in the future.

  8. Mexican propolis flavonoids affect photosynthesis and seedling growth.

    Science.gov (United States)

    King-Díaz, Beatriz; Granados-Pineda, Jessica; Bah, Mustapha; Rivero-Cruz, J Fausto; Lotina-Hennsen, Blas

    2015-10-01

    As a continuous effort to find new natural products with potential herbicide activity, flavonoids acacetin (1), chrysin (2) and 4',7-dimethylnarangenin (3) were isolated from a propolis sample collected in the rural area of Mexico City and their effects on the photosynthesis light reactions and on the growth of Lolium perenne, Echinochloa crus-galli and Physalis ixocarpa seedlings were investigated. Acacetin (1) acted as an uncoupler by enhancing the electron transport under basal and phosphorylating conditions and the Mg(2+)-ATPase. Chrysin (2) at low concentrations behaved as an uncoupler and at concentrations up to 100 μM its behavior was as a Hill reaction inhibitor. Finally, 4',7-dimethylnarangenin (3) in a concentration-dependent manner behaved as a Hill reaction inhibitor. Flavonoids 2 and 3 inhibited the uncoupled photosystem II reaction measured from water to 2,5-dichloro-1,4-benzoquinone (DCBQ), and they did not inhibit the uncoupled partial reactions measured from water to sodium silicomolybdate (SiMo) and from diphenylcarbazide (DPC) to diclorophenol indophenol (DCPIP). These results indicated that chrysin and 4',7-dimethylnarangenin inhibited the acceptor side of PS II. The results were corroborated with fluorescence of chlorophyll a measurements. Flavonoids also showed activity on the growth of seedlings of Lolium perenne and Echinochloa crus-galli. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Identification of MiRNAs Affecting the Establishment of Brassica Alboglabra Seedling

    Directory of Open Access Journals (Sweden)

    Rongfang Guo

    2016-11-01

    Full Text Available MicroRNAs (miRNAs are important for plant development including seed formation, dormancy, and germination, as well as seedling establishment. The Brassica vegetable seedling establishment stage influences the development of high quality seedlings, but also affects the nutrient content of sprouts. Chinese kale (Brassica alboglabra seedlings at different growth stages were used to construct two small-RNA (sRNA libraries. We comprehensively analyzed the miRNAs in 2- and 9-day-old seedlings. An average of 11,722,490 clean reads were generated after removing low-quality reads and adapter contaminants. The results revealed that 37.65% and 26.69% of the sRNAs in 2- and 9-day-old seedlings, respectively, were 24 nt long. In total, 254 known mature miRNA sequences from 228 miRNA families and 343 novel miRNAs were identified. Of these miRNAs, 224 were differentially expressed between the two analyzed libraries. The most abundant miRNAs identified by sequence homology were miR156, miR167, and miR157, each with more than 100,000 sequenced reads. Compared with the expression levels in 2-day-old seedlings, MiR8154 and miR390 were the most up- and down-regulated miRNAs respectively in 9-day-old seedlings. Gene ontology enrichment analysis of the differentially expressed-miRNA target genes affecting biological processes revealed that most genes were in the regulation of transcription category. Additionally, the expression patterns of some miRNAs and target genes were validated by quantitative real-time polymerase chain reaction. We determined that development-associated miRNAs (e.g., bal-miR156/157/159/166/167/172/396, were highly-expressed during seedling-establishment stage, as were stress-related (bal-miR408 and metabolism-related (bal-miR826 miRNAs. Combined with the low level of targets SPL9 and AP2, it was concluded that miR156-SPL9 and miR172-AP modules play key roles during the B. alboglabra seedling establishment stage.

  10. Butterfly, seedling, sapling and tree diversity and composition is a fire-affected Bornean rainforest

    NARCIS (Netherlands)

    Cleary, D.F.R.; Priadjati, A.; Suryokusumo, B.K.; Menken, S.B.J.

    2006-01-01

    Fire-affected forests are becoming an increasingly important component of tropical landscapes. The impact of wildfires on rainforest communities is, however, poorly understood. In this study the density, species richness and community composition of seedlings, saplings, trees and butterflies were as

  11. Butterfly, seedling, sapling and tree diversity and composition in a fire-affected Bornean rainforest

    NARCIS (Netherlands)

    Cleary, D.F.R.; Priadjati, A.; Suryokusumo, B.K.; Menken, S.B.J.

    2006-01-01

    Fire-affected forests are becoming an increasingly important component of tropical landscapes. The impact of wildfires on rainforest communities is, however, poorly understood. In this study the density, species richness and community composition of seedlings, saplings, trees and butterflies were as

  12. Warming and neighbor removal affect white spruce seedling growth differently above and below treeline.

    Science.gov (United States)

    Okano, Kyoko; Bret-Harte, M Syndonia

    2015-01-01

    Climate change is expected to be pronounced towards higher latitudes and altitudes. Warming triggers treeline and vegetation shifts, which may aggravate interspecific competition and affect biodiversity. This research tested the effects of a warming climate, habitat type, and neighboring plant competition on the establishment and growth of white spruce (Picea glauca (Moench) Voss) seedlings in a subarctic mountain region. P. glauca seedlings were planted in June 2010 under 4 different treatments (high/control temperatures, with/without competition) in 3 habitats (alpine ridge above treeline/tundra near treeline /forest below treeline habitats). After two growing seasons in 2011, growth, photosynthesis and foliar C and N data were obtained from a total of 156, one-and-a-half year old seedlings that had survived. Elevated temperatures increased growth and photosynthetic rates above and near treeline, but decreased them below treeline. Competition was increased by elevated temperatures in all habitat types. Our results suggest that increasing temperatures will have positive effects on the growth of P. glauca seedlings at the locations where P. glauca is expected to expand its habitat, but increasing temperatures may have negative effects on seedlings growing in mature forests. Due to interspecific competition, possibly belowground competition, the upslope expansion of treelines may not be as fast in the future as it was the last fifty years.

  13. Soil Type Affects Pinus ponderosa var. scopulorum (Pinaceae Seedling Growth in Simulated Drought Experiments

    Directory of Open Access Journals (Sweden)

    Alexander J. Lindsey

    2013-07-01

    Full Text Available Premise of the study: Effects of drought stress and media type interactions on growth of Pinus ponderosa var. scopulorum germinants were investigated. Methods and Results: Soil properties and growth responses under drought were compared across four growth media types: two native soils (dolomitic limestone and granite, a soil-less industry standard conifer medium, and a custom-mixed conifer medium. After 35 d of growth, the seedlings under drought stress (reduced watering produced less shoot and root biomass than watered control seedlings. Organic media led to decreased root biomass, but increased root length and shoot biomass relative to the mineral soils. Conclusions: Media type affected root-to-shoot biomass partitioning of P. ponderosa var. scopulorum, which may influence net photosynthetic rates, growth, and long-term seedling survival. Further work should examine how specific soil properties like bulk density and organic matter influence biomass allocation in greenhouse studies.

  14. Recruitment dynamics mediated by ungulate herbivory can affect species coexistence for tree seedling assemblages

    Directory of Open Access Journals (Sweden)

    Chi-Yu Weng

    2017-08-01

    Full Text Available The best-known mechanism that herbivory affects species coexistence of tree seedlings is negative density-dependency driven by specialist natural enemies. However, in a forest with intense herbivory by non-specialists, what causes a diversifying seedling bank if rare species do not benefit from negative density-dependency in dominant species? We hypothesize that generalist herbivores can cause unevenly distributed species-specific mortality, which mediates recruitment dynamics and therefore affects species coexistence. To answer this question, we conducted a fence-control experiment in a montane cloud forest, Taiwan, and found that herbivorous damages were mainly caused by ungulates, which are generalists. We explored ungulate herbivory effects on recruitment dynamics by censusing tree seedling dynamics for three years. We found that herbivorous damages by ungulates significantly cause seedling death, mostly at their early stage of establishment. The percentage of death caused by herbivory varied among species. In particular, nurse plants and seedling initial height help shade-tolerant species to persist under such intense herbivory. Whereas, deaths caused by other factors occurred more often in older seedlings, with a consistent low percentage among species. We then tested species coexistence maintenance by dynamic modelling under different scenarios of ungulate herbivory. Raising percentages of death by herbivory changes relative species abundances by suppressing light-demanding species and increasing shade-tolerant species. Density-dependent mortality immediately after bursts of recruitments can suppress dominance of abundant species. With ungulate herbivory, fluctuating recruitment further prevent rare species from apparent competition induced by abundant species. Such bio-processes can interact with ungulate herbivory so that long-term coexistence can be facilitated.

  15. Comparison of oak and sugar maple distribution and regeneration in central Illinois upland oak forests

    Science.gov (United States)

    Peter J. Frey; Scott J. Meiners

    2014-01-01

    Changes in disturbance frequencies, habitat fragmentation, and other biotic pressures are allowing sugar maple (Acer saccharum) to displace oak (Quercus spp.) in the upland forest understory. The displacement of oaks by sugar maples represents a major management concern throughout the region. We collected seedling microhabitat data...

  16. The Maple Sugar Festival

    Science.gov (United States)

    Johnston, Basil

    1978-01-01

    Describing the Iroquoi's Maple Sugar Festival, this article details the symbolism of renewal, becoming, and regeneration celebrated by the Iroquoi as the sap from the maple trees begins to flow each year. The symbolic role of woman, the sweet sap itself, and man's fellow creatures are described. (JC)

  17. Genetics Home Reference: maple syrup urine disease

    Science.gov (United States)

    ... links) Genetic Testing Registry: Classical maple syrup urine disease Genetic Testing Registry: Intermediate maple syrup urine disease Genetic Testing Registry: Maple syrup urine disease Other Diagnosis ...

  18. Altering the axial light gradient affects photomorphogenesis in emerging seedlings of Zea mays L

    Science.gov (United States)

    Parks, B. M.; Poff, K. L.

    1986-01-01

    The axial (longitudinal) red light gradient (632 nanometers) of 4 day old dark-grown maize seedlings is increased by staining the peripheral cells of the coleoptile. The magnitude of increase in the light gradient is dependent solely on the light-absorbing qualities of the stain used. Metanil yellow has no effect on the axial red-light gradient, while methylene blue causes a large increase in this light gradient. These stains did not affect growth in darkness or the sensitivity of mesocotyl elongation to red light. However, mesocotyl elongation was altered for the dark-grown seedlings stained with methylene blue when these seedlings were transplanted, covered with soil, and permitted to emerge under natural lighting conditions. These observations are consistent with the idea that there is a single perceptive site below the coleoptilar node, and suggest that this perceptive site gives the actinic light which has traveled downward through the length of the shoot from an entry point in the plant tip region.

  19. Substrates and nutrient addition rates affect morphology and physiology of Pinus leiophylla seedlings in the nursery stage

    Directory of Open Access Journals (Sweden)

    Buendía_Velázquez MV

    2016-10-01

    Full Text Available Production of forest seedlings is expensive mainly due to the use of inputs such as peat moss and fertilizers. Seedling survival in field conditions is low when seedlings with limited internal nutrient reserves are used in low fertility sites. In this work, raw sawdust and exponential fertilization were tested against peat-moss and constant fertilization, the common components of containerized seedling production systems in Mexico. The experiment was carried out under nursery conditions by using a complete randomized experimental design with a 2×2 factorial arrangement. Two substrates   peat-moss (PM and sawdust (SA   and two nutrient addition rates   constant (CR and exponential (ER   were tested. The response of seedlings was assessed based on diameter at the root collar, seedling height, dry weight (shoot, root, total and 100-needle, Dickson quality index (DQI, slenderness index (SI, and foliar nutrient concentrations and contents. Analysis of variance indicated that the substrate significantly affect all dry weights, with the greatest biomass observed for PM. Similarly, DQI and SI were affected by the substrate, with PM showing the best DQI and highest SI. Neither plant quality variables nor dry weights were affected by nutrient addition rates. Both substrate and nutrient addition rate significantly affected N, P, and K foliar concentrations. At the end of the production cycle, SA promoted higher foliar concentrations of N and P than PM, but not those of K. This suggests that K limited the growth of seedlings in sawdust, likely due to the low capacity of this substrate to adsorb K. ER produced needle concentrations of N, P, and K significantly higher than those of CR (2.65 vs. 2.26 %, 2303 vs. 2011 ppm, and 4235 vs. 3949 ppm, respectively. Our results indicate that ER is likely to give rise to more suited seedlings for outplanting in low fertility sites than CR.

  20. MAPLE deposition of nanomaterials

    Energy Technology Data Exchange (ETDEWEB)

    Caricato, A.P., E-mail: annapaola.caricato@le.infn.it [Department of Mathematics and Physics “E. De Giorgi”, University of Salento, Via Arnesano, I-73100 Lecce (Italy); Arima, V.; Catalano, M. [National Nanotechnology Laboratory (NNL), CNR Istituto Nanoscienze, c/o Distretto Tecnologico, Via Arnesano n. 16, I-73100 Lecce (Italy); Cesaria, M. [Department of Mathematics and Physics “E. De Giorgi”, University of Salento, Via Arnesano, I-73100 Lecce (Italy); Cozzoli, P.D. [Department of Mathematics and Physics “E. De Giorgi”, University of Salento, Via Arnesano, I-73100 Lecce (Italy); National Nanotechnology Laboratory (NNL), CNR Istituto Nanoscienze, c/o Distretto Tecnologico, Via Arnesano n. 16, I-73100 Lecce (Italy); Martino, M. [Department of Mathematics and Physics “E. De Giorgi”, University of Salento, Via Arnesano, I-73100 Lecce (Italy); Taurino, A.; Rella, R. [Institute for Microelectronics and Microsystems, IMM-CNR, Via Monteroni, I-73100 Lecce (Italy); Scarfiello, R. [National Nanotechnology Laboratory (NNL), CNR Istituto Nanoscienze, c/o Distretto Tecnologico, Via Arnesano n. 16, I-73100 Lecce (Italy); Tunno, T. [Department of Mathematics and Physics “E. De Giorgi”, University of Salento, Via Arnesano, I-73100 Lecce (Italy); Zacheo, A. [Department of Mathematics and Physics “E. De Giorgi”, University of Salento, Via Arnesano, I-73100 Lecce (Italy); National Nanotechnology Laboratory (NNL), CNR Istituto Nanoscienze, c/o Distretto Tecnologico, Via Arnesano n. 16, I-73100 Lecce (Italy)

    2014-05-01

    The matrix-assisted pulsed laser evaporation (MAPLE) has been recently exploited for depositing films of nanomaterials by combining the advantages of colloidal inorganic nanoparticles and laser-based techniques. MAPLE-deposition of nanomaterials meeting applicative purposes demands their peculiar properties to be taken into account while planning depositions to guarantee a congruent transfer (in terms of crystal structure and geometric features) and explain the deposition outcome. In particular, since nanofluids can enhance thermal conductivity with respect to conventional fluids, laser-induced heating can induce different ablation thermal regimes as compared to the MAPLE-treatment of soft materials. Moreover, nanoparticles exhibit lower melting temperatures and can experience pre-melting phenomena as compared to their bulk counterparts, which could easily induce shape and or crystal phase modification of the material to be deposited even at very low fluences. In this complex scenario, this review paper focuses on examples of MAPLE-depositions of size and shape controlled nanoparticles for different applications highlights advantages and challenges of the MAPLE-technique. The influence of the deposition parameters on the physical mechanisms which govern the deposition process is discussed.

  1. Effects of Nitrogen Fertilization on Potato Leafhopper (Hemiptera: Cicadellidae) and Maple Spider Mite (Acari: Tetranychidae) on Nursery-Grown Maples.

    Science.gov (United States)

    Prado, Julia; Quesada, Carlos; Gosney, Michael; Mickelbart, Michael V; Sadof, Clifford

    2015-06-01

    Although leaf nitrogen (N) has been shown to increase the suitability of hosts to herbivorous arthropods, the responses of these pests to N fertilization on susceptible and resistant host plants are not well characterized. This study determined how different rates of N fertilization affected injury caused by the potato leafhopper (Empoasca fabae Harris) and the abundance of maple spider mite (Oligonychus aceris (Shimer)) on 'Red Sunset' red maple (Acer rubrum) and 'Autumn Blaze' Freeman maple (Acer×freemanii) during two years in Indiana. N fertilization increased leaf N concentration in both maple cultivars, albeit to a lesser extent during the second year of the study. Overall, Red Sunset maples were more susceptible to E. fabae injury than Autumn Blaze, whereas Autumn Blaze maples supported higher populations of O. aceris. Differences in populations of O. aceris were attributed to differences between communities of stigmaeid and phytoseiid mites on each cultivar. Injury caused by E. fabae increased with N fertilization in a dose-dependent manner in both cultivars. Although N fertilization increased the abundance of O. aceris on both maple cultivars, there was no difference between the 20 and 40 g rates. We suggest the capacity of N fertilization to increase O. aceris on maples could be limited at higher trophic levels by the community of predatory mites.

  2. Sunflower seedlings dry matter content as affected by chemical treatment and storage length

    Directory of Open Access Journals (Sweden)

    Mrđa Jelena

    2011-01-01

    Full Text Available Chemical treatment of seed is a common crop protection measure. In the case of sunflower seed, fungicides are used regularly and insecticides at an increasing rate. In some cases, sunflower hybrid seed not planted in the first year is planted in the second or even third year after production. Seed vigour decreases gradually over time, which negatively affects seed emergence and subsequent plant growth and development. Seed with high vigour is expected to germinate quickly, producing seedlings that grow fast and uniformly. The objective of this study was to assess the effects of seed chemical treatment and storage length on seedling dry matter content in different sunflower hybrids. The study included several variants with fungicide and pesticide treatments and an untreated control. In the case of the hybrid NS-H-111, highest values of the studied characteristic were recorded in the control and directly after chemical treatment. In the case of the hybrid Sremac, the lowest value was recorded in seed treatment with benomyl+metalaxyl, highest in the treatments directly after chemical treatment and in seed stored for six months. In the case of the hybrid Šumadinac, highest values were recorded in the control and in seed treatment with fludioxonil+metalaxyl, the lowest in seed treatment with fludioxonil+metalaxyl+im idacloprid. Regarding the effect of different seed storage periods, highest values of the studied characteristic were recorded shortly after chemical treatment and in seed stored for six months.

  3. 7 CFR 1437.107 - Maple sap.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Maple sap. 1437.107 Section 1437.107 Agriculture... Yield Coverage Using Actual Production History § 1437.107 Maple sap. (a) NAP assistance for maple sap is limited to maple sap produced on private property for sale as sap or syrup. Eligible maple sap must be...

  4. Seed trait-mediated selection by rodents affects mutualistic interactions and seedling recruitment of co-occurring tree species.

    Science.gov (United States)

    Zhang, Hongmao; Yan, Chuan; Chang, Gang; Zhang, Zhibin

    2016-02-01

    As mutualists, seed dispersers may significantly affect mutualistic interactions and seedling recruitment of sympatric plants that share similar seed dispersers, but studies are rare. Here, we compared seed dispersal fitness in two co-occurring plant species (Armeniaca sibirica and Amygdalus davidiana) that inhabit warm temperate deciduous forest in northern China. We tested the hypothesis that seed trait-mediated selection by rodents may influence mutualistic interactions with rodents and then seedling establishment of co-occurring plant species. A. davidiana seeds are larger and harder (thick endocarps) than A. sibirica seeds, but they have similar levels of nutrients (crude fat, crude protein), caloric value and tannin. More A. sibirica seedlings are found in the field. Semi-natural enclosure tests indicated that the two seed species were both harvested by the same six rodent species, but that A. sibirica had mutualistic interactions (scatter hoarding) with four rodent species (Apodemus peninsulae, A. agrarius, Sciurotamias davidianus, Tamias sibiricus), and A. davidiana with only one (S. davidianus). Tagged seed dispersal experiments in the field indicated that more A. sibirica seeds were scatter-hoarded by rodents, and more A. sibirica seeds survived to the next spring and became seedlings. A. sibirica seeds derive more benefit from seed dispersal by rodents than A. davidiana seeds, particularly in years with limited seed dispersers, which well explained the higher seedling recruitment of A. sibirica compared with that of A. davidiana under natural conditions. Our results suggest that seed dispersers may play a significant role in seedling recruitment and indirect competition between co-occurring plant species.

  5. Spread intensity and invasiveness of sycamore maple (Acer pseudoplatanus L. in Lithuanian forests

    Directory of Open Access Journals (Sweden)

    Straigyte L

    2015-03-01

    Full Text Available The primary objectives of this study were to estimate seedling abundance, spread intensity, and invasiveness of sycamore maple (Acer pseudoplatanus L. in Lithuanian forests. The species was introduced to Lithuania in 1802, and since then has subsequently become gradually invasive. Seedling understory abundance, colonization and dispersal were investigated in six forest blocks covering the principal sycamore distribution areas in southwestern Lithuania. Seedlings height and densities in the undestory were evaluated, and seedlings assigned to four height groups. Species invasiveness was estimated applying the Pest Plant Prioritization Process (PPPP, based on the Analytic Hierarchy Process (AHP method. Results showed the average spread distance from the parent tree was 257 m, with a mean seedling number per hectare of 2064. Sycamore maple invasive score was 0.6426 (range: 0-1, the current relative to potential distribution rating was 0.57, and the social, environmental, and economic impact score was 0.1682. Such values were used to assess the Pest Plant Score for sycamore maple, obtaining a value (0.3537 lower than expectations (0.5. Results indicated that the species exhibits invasive properties and a rapid spread in the study area. Some implications of the above results in view of the upcoming climate change and the use of sycamore maple in Lithuanian forest plantations are discussed.

  6. Seedling growth of maize (Zea mays L. inbred lines affected by seed treatment with pesticides

    Directory of Open Access Journals (Sweden)

    Tamindžić Gordana D.

    2016-01-01

    Full Text Available Seed treatment is a common way of fungicide and insecticide use nowadays, since this way of pesticide application can provide the best protection in the vicinity of the future plant. The aim of research was to evaluate the effects of different seed treatments on germination and seedling growth in three maize inbred lines. The research included the seed treatment with several combinations of a fungicide Maxim XL 035-FS (a.i. metalaxil-M + fludioxonil and neonicotinoid insecticides Gaucho 600-FS (a.i. imidacloprid and Cruiser 350-FS (a.i. thiamethoxam, as well as untreated seed (control. The results indicated that inbred lines 21202 x 21101 NS and 317659 NS had a highly vigourous seed which was not affected by the seed treatments. The seed treatments with Maxim XL 035- FS+Gaucho 600-FS and Maxim XL 035-FS+Cruiser 350-FS led to a decrease in germination (90.25% and 89.50%, respectively of maize inbred line 306081 NS as well as a decrease in root length (126.75 mm and 125.25 mm, respectively and dry root weight (0.135 g and 0.1875 g, respectively of maize inbred line 21202 x 21101 NS. All seed treatments had positive effects on root growth, as well as on fresh root weight of maize inbred lines 306081 NS and 317659 NS. [Projekat Ministarstva nauke Republike Srbije, br. TR 31073: Improvement of maize and sorghum under stress

  7. Photocontrol of Anthocyanin Synthesis: VII. Factors Affecting the Spectral Sensitivity of Anthocyanin Synthesis in Young Seedlings.

    Science.gov (United States)

    Mancinelli, A L; Walsh, L

    1979-05-01

    Light-dependent anthocyanin synthesis is a typical high irradiance response (HIR) of plant photomorphogenesis. The spectral sensitivity of this response in young seedlings of cabbage and tomato is strongly affected by the length and mode of application of the light treatments. This observation suggests that the different experimental conditions, used in different action spectroscopy studies, might have been responsible, at least in part, for some of the reported differences in the characteristics of the HIR action spectra of different response-system combinations. In both cabbage and tomato, the values of the far red/blue, far red/red, and blue/red action ratios increase with increasing durations of the light treatments; this finding is in agreement with hypotheses of K. M. Hartmann (1966, 1967) and E. Schäfer (1975) for phytochrome action in the HIR. The similarity in the trend of change of the values of the action ratios suggests the possibility that the photomorphogenic pigment system, involved in the photoregulation of anthocyanin synthesis, may be the same in cabbage and tomato, even though there are some differences in the spectral sensitivity of the response between the two species.

  8. Interaction with ectomycorrhizal fungi and endophytic Methylobacterium affects nutrient uptake and growth of pine seedlings in vitro.

    Science.gov (United States)

    Pohjanen, Johanna; Koskimäki, Janne J; Sutela, Suvi; Ardanov, Pavlo; Suorsa, Marja; Niemi, Karoliina; Sarjala, Tytti; Häggman, Hely; Pirttilä, Anna Maria

    2014-09-01

    Tissues of Scots pine (Pinus sylvestris L.) contain several endophytic microorganisms of which Methylobacterium extorquens DSM13060 is a dominant species throughout the year. Similar to other endophytic bacteria, M. extorquens is able to colonize host plant tissues without causing any symptoms of disease. In addition to endophytic bacteria, plants associate simultaneously with a diverse set of microorganisms. Furthermore, plant-colonizing microorganisms interact with each other in a species- or strain-specific manner. Several studies on beneficial microorganisms interacting with plants have been carried out, but few deal with interactions between different symbiotic organisms and specifically, how these interactions affect the growth and development of the host plant. Our aim was to study how the pine endophyte M. extorquens DSM13060 affects pine seedlings and how the co-inoculation with ectomycorrhizal (ECM) fungi [Suillus variegatus (SV) or Pisolithus tinctorius (PT)] alters the response of Scots pine. We determined the growth, polyamine and nutrient contents of inoculated and non-inoculated Scots pine seedlings in vitro. Our results show that M. extorquens is able to improve the growth of seedlings at the same level as the ECM fungi SV and PT do. The effect of co-inoculation using different symbiotic organisms was seen in terms of changes in growth and nutrient uptake. Inoculation using M. extorquens together with ECM fungi improved the growth of the host plant even more than single ECM inoculation. Symbiotic organisms also had a strong effect on the potassium content of the seedling. The results indicate that interaction between endophyte and ECM fungus is species dependent, leading to increased or decreased nutrient content and growth of pine seedlings.

  9. Higher-order interaction between molluscs and sheep affecting seedling numbers in grassland

    Science.gov (United States)

    Clear Hill, B. H.; Silvertown, J.

    Vertebrate and invertebrate herbivores are both important in mesotrophic grasslands and these two different classes of herbivore potentially interact in their effect upon plant populations. We used two field experiments to test for higher order interactions (HOIs) among sheep, slugs and seedlings, using the mechanistic definition that an HOI occurs when the presence of one species modifies the interaction between two others. In each experiment slug addition and slug-removal treatments were nested inside treatments that altered sheep grazing intensity and timing, and the emergence, of seedlings from experimentally sown seeds was monitored. In Experiment 1, seedling numbers of Cerastium fontanum were increased by intense summer grazing by sheep in both slug-addition and slugremoval treatment, but winter grazing by sheep only increased seedling emergence if slugs were removed. In Experiment 2, winter grazing by sheep significantly reduced total seedling emergence of four species sown ( Lotus corniculatus, Plantago lanceolata, Leucanthemum vulgare, Achillea millefolium), but the effect was only seen where slugs were removed. Though the experimental system is a relatively simple one with only four components (sheep, slugs, seedlings and the matrix vegetation), higher order interactions, a combination of direct and indirect effects and possible switching behaviour by slugs are all suggested by our results.

  10. Can environmental variation affect seedling survival of plants in northeastern Mexico?

    Directory of Open Access Journals (Sweden)

    García Jaime F.

    2011-01-01

    Full Text Available The effects of global warming increase the frequency and intensity of many climate events such as rainfall. We evaluated the effects of environmental conditions on early stage seedling survival of the native thorn scrub species Caesalpinia mexicana A. Gray, Celtis pallida Torr., Cordia boissieri A. DC., and Ebenopsis ebano (Berland. Barneby and J.W. Grimes, during the summer of 2009 and 2010. The experimental design had two factors, two levels of rainfall and three microhabitats of thorn scrub: (i open interspace, (ii thorn scrub edge and (iii under the canopy of dense thorn scrub. In dense thorn scrub, seedling survival was higher for Caesalpinia mexicana and Celtis pallida, and for Cordia boissieri and Ebenopsis ebano seedling survival was higher in dense thorn scrub and thorn scrub edge. The effect of rainfall on seedling survival depended on the year. Rainfall in 2010 and dense thorn scrub increased seedling survival of native species. For survival, the limiting factors of microhabitats appear to change across the years. Besides rainfall events, biological aspects like competition and mycorrhiza effects would need to be considered in models of plant establishment.

  11. Plant growth-promoting rhizobacteria affect the growth and nutrient uptake of Fraxinus americana container seedlings.

    Science.gov (United States)

    Liu, Fangchun; Xing, Shangjun; Ma, Hailin; Du, Zhenyu; Ma, Bingyao

    2013-05-01

    Plant growth-promoting rhizobacteria (PGPR) are important catalysts that regulate the functional properties of agricultural systems. However, there is little information on the effect of PGPR inoculation on the growth and nutrient accumulation of forest container seedlings. This study determined the effects of a growth medium inoculated with PGPR on the nutrient uptake, nutrient accumulation, and growth of Fraxinus americana container seedlings. PGPR inoculation with fertilizer increased the dry matter accumulation of the F. americana aerial parts with delayed seedling emergence time. Under fertilized conditions, the accumulation time of phosphorous (P) and potassium (K) in the F. americana aerial parts was 13 days longer due to PGPR inoculation. PGPR increased the maximum daily P and K accumulations in fertilized seedlings by 9.31 and 10.44 %, respectively, but had little impact on unfertilized ones. Regardless of fertilizer application, the root exudates, namely sugars, amino acids, and organic acids significantly increased because of PGPR inoculation. PGPR inoculation with fertilizer increased the root, shoot, and leaf yields by 19.65, 22.94, and 19.44 %, respectively, as well as the P and K contents by 8.33 and 10.60 %, respectively. Consequently, the N, P, and K uptakes increased by 19.85, 31.97, and 33.95 %, respectively. Hence, PGPR inoculation with fertilizer can be used as a bioenhancer for plant growth and nutrient uptake in forest container seedling nurseries.

  12. Flooding affects uptake and distribution of carbon and nitrogen in citrus seedlings.

    Science.gov (United States)

    Martínez-Alcántara, Belén; Jover, Sara; Quiñones, Ana; Forner-Giner, María Ángeles; Rodríguez-Gamir, Juan; Legaz, Francisco; Primo-Millo, Eduardo; Iglesias, Domingo J

    2012-08-15

    Soil flooding has been widely reported to affect large areas of the world. In this work, we investigated the effect of waterlogging on citrus carbon and nitrogen pools and partitioning. Influence on their uptake and translocation was also studied through ¹⁵N and ¹³C labeling to provide insight into the physiological mechanisms underlying the responses. The data indicated that flooding severely reduced photosynthetic activity and affected growth and biomass partitioning. Total nitrogen content and concentration in the plant also progressively decreased throughout the course of the experiment. After 36 days of treatment, nitrogen content of flooded plants had decreased more than 2.3-fold compared to control seedlings, and reductions in nitrogen concentration ranged from 21 to 55% (in roots and leaves, respectively). Specific absorption rate and transport were also affected, leading to important changes in the distribution of this element inside the plant. Additionally, experiments involving labeled nitrogen revealed that ¹⁵N uptake rate and accumulation were drastically decreased at the end of the experiment (93% and 54%, respectively). ¹³CO₂ assimilation into the plant was strongly reduced by flooding, with δ¹³C reductions ranging from 22 to 37% in leaves and roots, respectively. After 36 days, the relative distribution of absorbed ¹³C was also altered. Thus, ¹³C recovery in flooded leaves increased compared to controls, whereas roots exhibited the opposite pattern. Interestingly, when carbohydrate partitioning was examined, the data revealed that sucrose concentration was augmented significantly in roots (37-56%), whereas starch was reduced. In leaves, a marked increase in sucrose was detected from the first sampling onwards (36-66%), and the same patter was observed for starch. Taken together, these results indicate that flooding altered carbon and nitrogen pools and partitioning in citrus. On one hand, reduced nitrogen concentration appears to

  13. Maturation of sugar maple seed

    Science.gov (United States)

    Clayton M., Jr. Carl; Albert G., Jr. Snow; Albert G. Snow

    1971-01-01

    The seeds of a sugar maple tree (Acer saccharum Marsh.) do not mature at the same time every year. And different trees mature their seeds at different times. So time of year is not a reliable measure of when seeds are ripe. Better criteria are needed. In recent studies we have found that moisture content and color are the best criteria for judging when sugar maple...

  14. Leaf age affects the responses of foliar injury and gas exchange to tropospheric ozone in Prunus serotina seedlings

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Jianwei, E-mail: jianweizhang@fs.fed.u [Environmental Resources Research Institute, Pennsylvania State University, University Park, PA 16802 (United States); School of Forest Resources, Pennsylvania State University, University Park, PA 16802 (United States); Schaub, Marcus; Ferdinand, Jonathan A. [Environmental Resources Research Institute, Pennsylvania State University, University Park, PA 16802 (United States); Skelly, John M. [Department of Plant Pathology, Pennsylvania State University, University Park, PA 16802 (United States); Steiner, Kim C. [School of Forest Resources, Pennsylvania State University, University Park, PA 16802 (United States); Savage, James E. [Department of Plant Pathology, Pennsylvania State University, University Park, PA 16802 (United States)

    2010-08-15

    We investigated the effect of leaf age on the response of net photosynthesis (A), stomatal conductance (g{sub wv}), foliar injury, and leaf nitrogen concentration (N{sub L}) to tropospheric ozone (O{sub 3}) on Prunus serotina seedlings grown in open-plots (AA) and open-top chambers, supplied with either carbon-filtered or non-filtered air. We found significant variation in A, g{sub wv}, foliar injury, and N{sub L} (P < 0.05) among O{sub 3} treatments. Seedlings in AA showed the highest A and g{sub wv} due to relatively low vapor pressure deficit (VPD). Older leaves showed significantly lower A, g{sub wv}, N{sub L}, and higher foliar injury (P < 0.001) than younger leaves. Leaf age affected the response of A, g{sub wv}, and foliar injury to O{sub 3}. Both VPD and N{sub L} had a strong influence on leaf gas exchange. Foliar O{sub 3}-induced injury appeared when cumulative O{sub 3} uptake reached 8-12 mmol m{sup -2}, depending on soil water availability. The mechanistic assessment of O{sub 3}-induced injury is a valuable approach for a biologically relevant O{sub 3} risk assessment for forest trees. - Ozone effects on symptom development and leaf gas exchange interacted with leaf age and N-content on black cherry seedlings.

  15. Competition for nitrogen between European beech and sycamore maple shifts in favour of beech with decreasing light availability.

    Science.gov (United States)

    Simon, Judy; Li, Xiuyuan; Rennenberg, Heinz

    2014-01-01

    Plant species use different strategies for maximizing growth and fitness under changing environmental conditions. At the ecosystem level, seedlings in particular compete with other vegetation components for light and nitrogen (N), which often constitute growth-limiting resources. In this study, we investigated the effect of light availability on the competition for N between seedlings of European beech and sycamore maple and analysed the consequences of this competition for the composition of N metabolites in fine roots. Our results show different strategies in N acquisition between beech and sycamore maple. Both species responded to reduced light availability by adapting their morphological and physiological traits with a decrease in biomass and net assimilation rate and an increase in specific leaf area and leaf area ratio. For beech seedlings, competition with sycamore maple led to a reduction in organic N uptake capacity. Reduced light availability led to a decrease in ammonium, but an increase in glutamine-N uptake capacity in sycamore maple. However, this response was stronger compared with that of beech and was accompanied by reduced growth. Thus, our results suggest better adaptation of N acquisition to reduced light availability in beech compared with sycamore maple seedlings.

  16. Calcium Addition Affects Germination and Early Seedling Growth of Sweet Sorghum under Saline Conditions

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    [Objective] This study aimed to determine the interactive effects of supple- mental Ca amendment and salinity on germination of sweet sorghum seeds in saline solution culture medium, and investigate the effects of different combinations of Na/Ca ratio in saline soils on the early growth of sweet sorghum plants. [Method] A germi- nation test and a greenhouse pot experiment were conducted to assess the interac- tive effects of calcium addition to culture medium on the germination and seedling growth of sweet sorghum (Sorghum saccharatum Moench) in saline soils with a range of NaYCa ratios. In the germination test, seeds were treated with different combinations of five calcium levels [0, 5, 10, 15, and 20 mmol/L Ca(NO3)2] and five salinity levels (0, 50, 100, 150, and 200 mmol/L NaCI). In the greenhouse experi- ment, seeds were sown in potting soils containing 3 salinity levels (2.3, 4.7 and 7.0 dS/m) and three Na:Ca ratios (10:0, 10:1, and 5:1). [Result] In the germination test, Ca addition at 5 mmol/L promoted germination by 5.5%, 9.9%, and 17.0% at the 3.4, 6.7 and 10.1 dS/m salinity levels. The higher Ca level (10 mmol/L) also in- creased germination by 9.1% and 7.8% at the 3.4 and 6.7 dS/m salinity levels. Then even higher Ca addition at 15 and 20 mmol/L appeared to promote germina- tion when culture media had high salinity (10.1 and 13.4 dS/m). In the greenhouse pot experiment, saline soil amended with supplemental Ca at the 2.3 and 4.7 dS/m salinity levels significantly promoted early seedling growth, with an increase of 6.8% to 28.2% in plant height and 14.3% to 67.9% in whole plant weight. From 28 to 42 d after seeding, the relative growth of seedling was increased by Ca addition, with a reduction of 49.5% to 66.0% in plant height and 4.8% to 61.9% in whole plant weight. From 42 to 56 d after seeding, however, the relative growth of seedling was significantly inhibited by Ca amendment. [Conclusion] Results of this study indicate that appropriate supplemental

  17. Response of sugar maple to calcium addition to northern hardwood forest.

    Science.gov (United States)

    Juice, Stephanie M; Fahey, Timothy J; Siccama, Thomas G; Driscoll, Charles T; Denny, Ellen G; Eagar, Christopher; Cleavitt, Natalie L; Minocha, Rakesh; Richardson, Andrew D

    2006-05-01

    Watershed budget studies at the Hubbard Brook Experimental Forest (HBEF), New Hampshire, USA, have demonstrated high calcium depletion of soil during the 20th century due, in part, to acid deposition. Over the past 25 years, tree growth (especially for sugar maple) has declined on the experimental watersheds at the HBEF. In October 1999, 0.85 Mg Ca/ha was added to Watershed 1 (W1) at the HBEF in the form of wollastonite (CaSiO3), a treatment that, by summer 2002, had raised the pH in the Oie horizon from 3.8 to 5.0 and, in the Oa horizon, from 3.9 to 4.2. We measured the response of sugar maple to the calcium fertilization treatment on W1. Foliar calcium concentration of canopy sugar maples in W1 increased markedly beginning the second year after treatment, and foliar manganese declined in years four and five. By 2005, the crown condition of sugar maple was much healthier in the treated watershed as compared with the untreated reference watershed (W6). Following high seed production in 2000 and 2002, the density of sugar maple seedlings increased significantly on W1 in comparison with W6 in 2001 and 2003. Survivorship of the 2003 cohort through July 2005 was much higher on W1 (36.6%) than W6 (10.2%). In 2003, sugar maple germinants on W1 were approximately 50% larger than those in reference plots, and foliar chlorophyll concentrations were significantly greater (0.27 g/m2 vs. 0.23 g/m2 leaf area). Foliage and fine-root calcium concentrations were roughly twice as high, and manganese concentrations twice as low in the treated than the reference seedlings in 2003 and 2004. Mycorrhizal colonization of seedlings was also much greater in the treated (22.4% of root length) than the reference sites (4.4%). A similar, though less dramatic, difference was observed for mycorrhizal colonization of mature sugar maples (56% vs. 35%). These results reinforce and extend other regional observations that sugar maple decline in the northeastern United States and southern Canada is

  18. Antioxidant enzyme and osmotic adjustment changes in bean seedlings as affected by biochar under salt stress.

    Science.gov (United States)

    Farhangi-Abriz, Salar; Torabian, Shahram

    2017-03-01

    Salinity damaged cellular membranes through overproduction of reactive oxygen species (ROS), while osmolytes and antioxidant capacities play a vital role in protecting plants from salinity caused oxidative damages. Biochar also could alleviate the negative impacts of salt stress in crops. The pot experiment was conducted to investigate the effects of biochar on some antioxidant enzyme activities and osmolyte adjustments of common bean (Phaseolus vulgaris L. cv. Derakhshan) under salinity stress. Bean plants were subjected to three salinity levels (non-saline, 6 and 12 dSm(-1) of NaCl) and biochar treatments (non-biochar, 10% and 20% total pot mass). Shoot and root dry weights of bean were decreased at two salt stress treatments. Salinity increased the activity of catalase (CAT), ascorbate peroxidase (APX), peroxidase (POD), polyphenol oxidase (PPO) and superoxide dismutase (SOD), and the content of malondialdehyde (MDA), oxygen radicals (O(2•-)), and hydrogen peroxide (H2O2) in leaf and root compared to control. Additionally, increased magnitudes of proline, glycine betaine, soluble sugar and soluble protein contents were more pronounced under 12 dSm(-1) NaCl than those under 6 dSm(-1) NaCl. In contrast, biochar applied to soil enhanced the shoot and root dry weight in comparison with the non-biochar treatment. Furthermore, all of the antioxidant activities of seedlings in soil treated with biochar, particularly at 20% biochar, declined. With the addition of biochar, the contents of MDA, O(2•-) and H2O2 displayed remarkable decrease, and the osmotic substances accumulation in leaves and roots also reduced. The presented results supported the view that biochar can contribute to protect common bean seedlings against NaCl stress by alleviating the oxidative stress. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Foliar Nutrient Distribution Patterns in Sympatric Maple Species Reflect Contrasting Sensitivity to Excess Manganese.

    Directory of Open Access Journals (Sweden)

    Denise R Fernando

    Full Text Available Sugar maple and red maple are closely-related co-occurring tree species significant to the North American forest biome. Plant abiotic stress effects including nutritional imbalance and manganese (Mn toxicity are well documented within this system, and are implicated in enhanced susceptibility to biotic stresses such as insect attack. Both tree species are known to overaccumulate foliar manganese (Mn when growing on unbuffered acidified soils, however, sugar maple is Mn-sensitive, while red maple is not. Currently there is no knowledge about the cellular sequestration of Mn and other nutrients in these two species. Here, electron-probe x-ray microanalysis was employed to examine cellular and sub-cellular deposition of excessively accumulated foliar Mn and other mineral nutrients in vivo. For both species, excess foliar Mn was deposited in symplastic cellular compartments. There were striking between-species differences in Mn, magnesium (Mg, sulphur (S and calcium (Ca distribution patterns. Unusually, Mn was highly co-localised with Mg in mesophyll cells of red maple only. The known sensitivity of sugar maple to excess Mn is likely linked to Mg deficiency in the leaf mesophyll. There was strong evidence that Mn toxicity in sugar maple is primarily a symplastic process. For each species, leaf-surface damage due to biotic stress including insect herbivory was compared between sites with acidified and non-acidified soils. Although it was greatest overall in red maple, there was no difference in biotic stress damage to red maple leaves between acidified and non-acidified soils. Sugar maple trees on buffered non-acidified soil were less damaged by biotic stress compared to those on unbuffered acidified soil, where they are also affected by Mn toxicity abiotic stress. This study concluded that foliar nutrient distribution in symplastic compartments is a determinant of Mn sensitivity, and that Mn stress hinders plant resistance to biotic stress.

  20. A Mutation in Arabidopsis SEEDLING PLASTID DEVELOPMENT1 Affects Plastid Differentiation in Embryo-Derived Tissues during Seedling Growth1[W][OA

    Science.gov (United States)

    Ruppel, Nicholas J.; Logsdon, Charles A.; Whippo, Craig W.; Inoue, Kentaro; Hangarter, Roger P.

    2011-01-01

    Oilseed plants like Arabidopsis (Arabidopsis thaliana) develop green photosynthetically active embryos. Upon seed maturation, the embryonic chloroplasts degenerate into a highly reduced plastid type called the eoplast. Upon germination, eoplasts redifferentiate into chloroplasts and other plastid types. Here, we describe seedling plastid development1 (spd1), an Arabidopsis seedling albino mutant capable of producing normal green vegetative tissues. Mutant seedlings also display defects in etioplast and amyloplast development. Precocious germination of spd1 embryos showed that the albino seedling phenotype of spd1 was dependent on the passage of developing embryos through the degreening and dehydration stages of seed maturation, suggesting that SPD1 is critical during eoplast development or early stages of eoplast redifferentiation. The SPD1 gene was found to encode a protein containing a putative chloroplast-targeting sequence in its amino terminus and also domains common to P-loop ATPases. Chloroplast localization of the SPD1 protein was confirmed by targeting assays in vivo and in vitro. Although the exact function of SPD1 remains to be defined, our findings reveal aspects of plastid development unique to embryo-derived cells. PMID:21045120

  1. Hylastes ater (Curculionidae: Scolytinae Affecting Pinus radiata Seedling Establishment in New Zealand

    Directory of Open Access Journals (Sweden)

    Stephen D. Reay

    2012-01-01

    Full Text Available The introduced pine bark beetle Hylastes ater has been present in New Zealand for around 100 years. The beetle has been a minor pest on pines. Research was undertaken to control the pest in the 1950s–1970s, with a biological control agent introduced with limited success. Following a reasonably long period with minimal research attention, renewed interest in developing a better understanding of the pest status was initiated in the mid to late 1990s. Subsequently, a significant amount of research was undertaken, with a number of studies exploring the role of this pest of exotic forests in New Zealand. These studies ranged from attempting to quantify damage to seedlings, evaluate the role of the beetle in vectoring sapstain fungi, explore options for management, and evaluate the potential for chemical and biological control. From these studies, a number of findings were made that are relevant to the New Zealand exotic forest industry and shed new light onto the role of secondary bark beetles globally.

  2. Soil base saturation combines with Beech Bark Disease to influence composition and structure of Sugar Maple-Beech forests in an acid rain-impacted region

    Science.gov (United States)

    Lawrence, Gregory B.; McDonnell, Todd C.; Sullivan, Timothy J.; Dovciak, Martin; Bailey, Scott W.; Antidormi, Michael; Zarfos, Michael R.

    2017-01-01

    Sugar maple, an abundant and highly valued tree species in eastern North America, has experienced decline from soil calcium (Ca) depletion by acidic deposition, while beech, which often coexists with sugar maple, has been afflicted with beech bark disease (BBD) over the same period. To investigate how variations in soil base saturation combine with effects of BBD in influencing stand composition and structure, measurements of soils, canopy, subcanopy, and seedlings were taken in 21 watersheds in the Adirondack region of NY (USA), where sugar maple and beech were the predominant canopy species and base saturation of the upper B horizon ranged from 4.4 to 67%. The base saturation value corresponding to the threshold for Al mobilization (16.8%) helped to define the species composition of canopy trees and seedlings. Canopy vigor and diameter at breast height (DBH) were positively correlated (P as base saturation increased, the average canopy position of beech decreased relative to sugar maple (P as red maple and black cherry, whereas in high-base saturation soils, sugar maple dominated the canopy. Where soils were beginning to recover from acidic deposition effects, sugar maple DBH and basal area increased progressively from 2000 to 2015, whereas for beech, average DBH did not change and basal area did not increase after 2010.

  3. Light affects the chloroplast ultrastructure and post-storage photosynthetic performance of watermelon (Citrullus lanatus) plug seedlings.

    Science.gov (United States)

    Duan, Qingqing; Jiang, Wu; Ding, Ming; Lin, Ye; Huang, Danfeng

    2014-01-01

    Watermelon [Citrullus lanatus (Thunb.) Matsum. and Nakai] plug seedlings were stored at 15°C in the light at a photosynthetic photon flux density of 15 µmol·m(-2)·s(-1) or in darkness for 6 days, to evaluate their chloroplast ultrastructure, and associated photosynthetic characteristics. Storage in the dark caused swelling, disordered granal arrangement, and starch grain disappearance in the chloroplasts. In contrast, the chloroplasts stored in the light were relatively normal. As a result, the light-stored seedlings had a significantly higher chlorophyll content, Fv/Fm, and Pn than did dark-stored seedlings. Regardless of whether the seedlings were stored in light or darkness, the Gs and Ls of the seedlings significantly decreased, while the Ci obviously increased when the Pn decreased after 6 days of storage. This result suggests that the decreased Pn is not solely a stomatal effect, as the effects on the chloroplasts contributed to this photosynthetic inhibition. Six days after transplanting, seedlings that were stored in the light or darkness for 2 or 4 days showed complete recovery of chloroplast ultrastructure, chlorophyll content, Fv/Fm, Gs and Pn. When the storage period increased to 6 days, the dark-stored seedlings had a significantly lower Fv/Fm and Pn than the light-stored and control seedlings 6 days after transplanting, which was mainly ascribed to incomplete recovery of chloroplast ultrastructure. Furthermore, the light-stored seedlings exhibited a significantly higher shoot dry weight during storage and a higher percentage dry weight increase after transplanting than the dark-stored seedlings. These effects were enhanced by prolonged storage (4 to 6 days). This study demonstrated that dim light during storage is beneficial for maintaining chloroplast ultrastructure as well as photosynthetic efficiency in watermelon seedlings, thus contributing to the rapid recovery of post-storage photosynthetic performance, which ensures the transplant quality

  4. Elevated CO2 affects secondary metabolites in Robinia pseudoacacia L. seedlings in Cd- and Pb-contaminated soils.

    Science.gov (United States)

    Jia, Xia; Zhao, Yonghua; Liu, Tuo; Huang, Shuping

    2016-10-01

    Secondary metabolites play important roles in plant interactions with the environment. The co-occurrence of heavy metal contamination of soils and rising atmospheric CO2 has important effects on plant. It is important to explore the ways in which production of plant secondary metabolites is affected by heavy metals under elevated atmospheric CO2. We examined the effects of elevated CO2 on secondary metabolite contents in Robinia pseudoacacia seedlings grown in Cd- and lead (Pb)-contaminated soils. The increase in secondary metabolites was greater under Cd + Pb exposure than under exposure to individual metals regardless of elevated CO2 with the exception of condensed tannins in leaves and total alkaloids in stems. Except for phenolic compounds and condensed tannins, elevated CO2 was associated with increased secondary metabolite contents in leaves and stems of plants exposed to Cd, Pb, and Cd + Pb compared to plants exposed to ambient CO2 + metals. Changes in saponins in leaves and alkaloids in stems were greater than changes in the other secondary metabolites. Significant interactive effects of CO2, Cd, and Pb on secondary metabolites were observed. Saponins in leaves and alkaloids in stems were more sensitive than other secondary metabolites to elevated CO2 + Cd + Pb. Elevated CO2 could modulate plant protection and defense mechanisms in R. pseudoacacia seedlings exposed to heavy metals by altering the production of secondary metabolites. The increased Cd and Pb uptake under elevated CO2 suggested that R. pseudoacacia may be used in the phytoremediation of heavy metal-contaminated soils under global environmental scenarios.

  5. Climate Change in the School Yard: Monitoring the Health of Acer Saccharum with A Maple Report Card

    Science.gov (United States)

    Carlson, M.; Diller, A.; Rock, B. N.

    2012-12-01

    K-12 Teachers and students engage in authentic science and a research partnership with scientists in Maple Watch, a University of New Hampshire outreach program. Maple Watch is a hands-on, inquiry-based program in which students learn about climate change and air quality as well as many other environmental stress factors which may affect the health of sugar maple. The iconic New England tree is slated to lose 52% of its range in this century. Maple Watch builds on the 20-year record of Forest Watch, a K-12 program in which students and teachers have contributed annual research specimens and data to a UNH study of tropospheric ozone and its impact on white pine (Pinus strobus). Maple Watch students monitor sugar maples (Acer saccharum) year-round for signals of strain and disease. Students report the first run in sap season, bud burst and leaf development, and leaf senescence and fall. Across New England the timing of these phenologic events is changing with climate warming. Students assess maple health with simple measures of leaf development in May, leaf senescence in early fall and bud quality in late fall. Simple student arithmetic rankings of leaf and bud health correlate with chlorophyll content and spectral reflectance measures that students can analyze and compare with researchers at UNH. Grading their trees for each test on a one-two-three scale, students develop a Maple Report Card for each type of measurement, which presents an annual portrait of tree health. Year-by-year, schools across the sugar maple's 31 million acre range could monitor changes in tree health. The change over time in maple health can be graphed in parallel with the Goddard Space Institute's Common Sense Climate Index. Four teachers, listed as co-authors here, began a pilot study with Maple Watch in 2010, contributing sap samples and sharing curricular activities with UNH. Pilot Maple Watch schools already manage stands of sugar maples and make maple syrup and are assisting in training

  6. 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.

  7. The presence of amino acids affects inorganic N uptake in non-mycorrhizal seedlings of European beech (Fagus sylvatica).

    Science.gov (United States)

    Stoelken, Gunda; Simon, Judy; Ehlting, Barbara; Rennenberg, Heinz

    2010-09-01

    To investigate the impact of organic N compounds for inorganic nitrogen uptake in the rhizosphere, we fed ammonium nitrate with or without amino acids (i.e., glutamine or arginine) to the roots of non-mycorrhizal beech (Fagus sylvatica L.) seedlings under controlled conditions at different levels of N availability. Uptake of individual N sources was determined from ¹⁵N (inorganic N) and ¹⁵N ¹³C (organic N) accumulation in the roots. In addition, gene fragments encoding proteins involved in N uptake and metabolism were cloned from beech for gene expression analyses by quantitative real-time PCR in the roots. Generally, ammonium was preferred over nitrate as N source. Organic N sources were taken up by beech roots as intact molecules. Uptake of organic N was significantly higher than inorganic N uptake, thus contributing significantly to N nutrition of beech. Depending on the level of N availability, inorganic N uptake was negatively affected by the presence of organic N sources. This result indicates an overestimation of the contribution of inorganic N uptake to N nutrition of beech in previous studies. Apparently, association with mycorrhizal fungi is not essential for organic N uptake by beech roots. Gene expression analyses showed that transcriptional regulation of the amino acid transporters FsCAT3, FsCAT5, FsAAT and FsAAP and the ammonium transporter FsAMT1.2 in the roots is involved in N nutrition of beech.

  8. Quantifying efficacy and limits of unmanned aerial vehicle (UAV) technology for weed seedling detection as affected by sensor resolution.

    Science.gov (United States)

    Peña, José M; Torres-Sánchez, Jorge; Serrano-Pérez, Angélica; de Castro, Ana I; López-Granados, Francisca

    2015-03-06

    In order to optimize the application of herbicides in weed-crop systems, accurate and timely weed maps of the crop-field are required. In this context, this investigation quantified the efficacy and limitations of remote images collected with an unmanned aerial vehicle (UAV) for early detection of weed seedlings. The ability to discriminate weeds was significantly affected by the imagery spectral (type of camera), spatial (flight altitude) and temporal (the date of the study) resolutions. The colour-infrared images captured at 40 m and 50 days after sowing (date 2), when plants had 5-6 true leaves, had the highest weed detection accuracy (up to 91%). At this flight altitude, the images captured before date 2 had slightly better results than the images captured later. However, this trend changed in the visible-light images captured at 60 m and higher, which had notably better results on date 3 (57 days after sowing) because of the larger size of the weed plants. Our results showed the requirements on spectral and spatial resolutions needed to generate a suitable weed map early in the growing season, as well as the best moment for the UAV image acquisition, with the ultimate objective of applying site-specific weed management operations.

  9. Quantifying Efficacy and Limits of Unmanned Aerial Vehicle (UAV Technology for Weed Seedling Detection as Affected by Sensor Resolution

    Directory of Open Access Journals (Sweden)

    José M. Peña

    2015-03-01

    Full Text Available In order to optimize the application of herbicides in weed-crop systems, accurate and timely weed maps of the crop-field are required. In this context, this investigation quantified the efficacy and limitations of remote images collected with an unmanned aerial vehicle (UAV for early detection of weed seedlings. The ability to discriminate weeds was significantly affected by the imagery spectral (type of camera, spatial (flight altitude and temporal (the date of the study resolutions. The colour-infrared images captured at 40 m and 50 days after sowing (date 2, when plants had 5–6 true leaves, had the highest weed detection accuracy (up to 91%. At this flight altitude, the images captured before date 2 had slightly better results than the images captured later. However, this trend changed in the visible-light images captured at 60 m and higher, which had notably better results on date 3 (57 days after sowing because of the larger size of the weed plants. Our results showed the requirements on spectral and spatial resolutions needed to generate a suitable weed map early in the growing season, as well as the best moment for the UAV image acquisition, with the ultimate objective of applying site-specific weed management operations.

  10. Growth, allocation and tissue chemistry of Picea abies seedlings affected by nutrient supply during the second growing season.

    Science.gov (United States)

    Kaakinen, Seija; Jolkkonen, Annika; Iivonen, Sari; Vapaavuori, Elina

    2004-06-01

    One-year-old Norway spruce (Picea abies (L.) Karst.) seedlings were grown hydroponically in a growth chamber to investigate the effects of low and high nutrient availability (LN; 0.25 mM N and HN; 2.50 mM N) on growth, biomass allocation and chemical composition of needles, stem and roots during the second growing season. Climatic conditions in the growth chamber simulated the mean growing season from May to early October in Flakaliden, northern Sweden. In the latter half of the growing season, biomass allocation changed in response to nutrient availability: increased root growth and decreased shoot growth led to higher root/shoot ratios in LN seedlings than in HN seedlings. At high nutrient availability, total biomass, especially stem biomass, increased, as did total nonstructural carbohydrate and nitrogen contents per seedling. Responses of stem chemistry to nutrient addition differed from those of adult trees of the same provenance. In HN seedlings, concentrations of alpha-cellulose, hemicellulose and lignin decreased in the secondary xylem. Our results illustrate the significance of retranslocation of stored nutrients to support new growth early in the season when root growth and nutrient uptake are still low. We conclude that nutrient availability alters allocation patterns, thereby influencing the success of 2-year-old Norway spruce seedlings at forest planting sites.

  11. In vitro zygotic embryo culture of Pinus peuce Gris.: Optimization of culture conditions affecting germination and early seedling growth

    Directory of Open Access Journals (Sweden)

    Stojičić Dragana

    2012-01-01

    Full Text Available This study reports a protocol for the germination and early seedling growth of Pinus peuce Gris. using zygotic embryo culture. In order to overcome seed dormancy and optimize organogenesis, the effect of nutritional, plant growth regulatory and physical factors on in vitro germination and growth of isolated mature zygotic embryos of P. peuce were investigated.

  12. Growth and morphology of Scirpus lacustris and S-maritimus seedlings as affected by water level and light availability

    NARCIS (Netherlands)

    Clevering, O.A.; Blom, C.W.P.M.; Van Vierssen, W.

    1996-01-01

    1. Adults of the emergent macrophytes Scirpus lacustris ssp. lacustris (S.l. lacustris), S. lacustris ssp. tabernaemontani (S.l. tabernaemontani) and S. maritimus occur along a gradient in water depth from deep to shallow water. This study examined whether seedlings of these taxa respond differently

  13. Seed Burial Depth and Soil Water Content Affect Seedling Emergence and Growth of Ulmus pumila var. sabulosa in the Horqin Sandy Land

    Directory of Open Access Journals (Sweden)

    Jiao Tang

    2016-01-01

    Full Text Available We investigated the effects of seed burial depth and soil water content on seedling emergence and growth of Ulmus pumila var. sabulosa (sandy elm, an important native tree species distributed over the European-Asian steppe. Experimental sand burial depths in the soil were 0.5, 1.0, 1.5, 2.0 and 2.5 cm, and soil water contents were 4%, 8%, 12% and 16% of field capacity. All two-way ANOVA (five sand burial depths and four soil water contents results showed that seed burial depths, soil water content and their interactions significantly affected all the studied plant variables. Most of the times, seedling emergence conditions were greater at the lower sand burial depths (less than 1.0 cm than at the higher (more than 1.0 cm seed burial depths, and at the lower water content (less than 12% than at the higher soil water content. However, high seed burial depths (more than 1.5 cm or low soil water content (less than 12% reduced seedling growth or change in the root/shoot biomass ratios. In conclusion, the most suitable range of sand burial was from 0.5 to 1.0 cm soil depth and soil water content was about 12%, respectively, for the processes of seedling emergence and growth. These findings indicate that seeds of the sandy elm should be kept at rather shallow soil depths, and water should be added up to 12% of soil capacity when conducting elm planting and management. Our findings could help to create a more appropriate sandy elm cultivation and understand sparse elm woodland recruitment failures in arid and semi-arid regions.

  14. Elevated atmospheric CO2 affected photosynthetic products in wheat seedlings and biological activity in rhizosphere soil under cadmium stress.

    Science.gov (United States)

    Jia, Xia; Liu, Tuo; Zhao, Yonghua; He, Yunhua; Yang, Mingyan

    2016-01-01

    The objective of this study was to investigate the effects of elevated CO2 (700 ± 23 μmol mol(-1)) on photosynthetic products in wheat seedlings and on organic compounds and biological activity in rhizosphere soil under cadmium (Cd) stress. Elevated CO2 was associated with decreased quantities of reducing sugars, starch, and soluble amino acids, and with increased quantities of soluble sugars, total sugars, and soluble proteins in wheat seedlings under Cd stress. The contents of total soluble sugars, total free amino acids, total soluble phenolic acids, and total organic acids in the rhizosphere soil under Cd stress were improved by elevated CO2. Compared to Cd stress alone, the activity of amylase, phenol oxidase, urease, L-asparaginase, β-glucosidase, neutral phosphatase, and fluorescein diacetate increased under elevated CO2 in combination with Cd stress; only cellulase activity decreased. Bacterial abundance in rhizosphere soil was stimulated by elevated CO2 at low Cd concentrations (1.31-5.31 mg Cd kg(-1) dry soil). Actinomycetes, total microbial abundance, and fungi decreased under the combined conditions at 5.31-10.31 mg Cd kg(-1) dry soil. In conclusion, increased production of soluble sugars, total sugars, and proteins in wheat seedlings under elevated CO2 + Cd stress led to greater quantities of organic compounds in the rhizosphere soil relative to seedlings grown under Cd stress only. Elevated CO2 concentrations could moderate the effects of heavy metal pollution on enzyme activity and microorganism abundance in rhizosphere soils, thus improving soil fertility and the microecological rhizosphere environment of wheat under Cd stress.

  15. Vine maple (Acer circinatum) clone growth and reproduction in managed and unmanaged coastal Oregon douglas-fir forests

    Science.gov (United States)

    O'Dea, Mary E.; Zasada, John C.; Tappeiner, John C.

    1995-01-01

    Vine maple (Acer circinatum Pursh.) clone development, expansion, and regeneration by seedling establishment were studied in 5-240 yr old managed and unmanaged Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) stands in coastal Oregon. Stem length, number of stems, and crown area were all significantly (P @10 m long and basal sprouts 1-2 m long; some stems had been pinned to the forest floor by fallen trees or branches and had layered. In stands >120 yr in age, clones were often quite complex, composed of several decumbent stems each of which connected the ramets of 1-10 new aerial stems. Vine maple clone expansion occurs by the layering of long aerial stems. Over 95% of the layered stems we observed had been pinned to the forest floor by fallen debris. Unsevered stems that we artificially pinned to the forest floor initiated roots within 1 yr. Thinning may favor clonal expansion because fallen slash from thinning often causes entire clones to layer, not just individual stems. Clonal vine maple seed production and seedling establishment occurred in all stages of stand development except dense, young stands following crown closure. There were more seedlings in thinned stands than in unthinned stands and in unburned clearcuts than in burned clearcuts.

  16. Nitrate reductase activity in cabbage (Brassica oleracae var. capitata seedlings affected by the different nitrogen fertilizer forms

    Directory of Open Access Journals (Sweden)

    Metin Turan

    2013-12-01

    Full Text Available The effect of different nitrogen fertilizer (potassium nitrate, ammonium nitrate, ammonium sulphate, urea and farmyard manure on nitrate reductase activity in cabbage (Brassica oleracea var. capitata seedlings were studied. pH of the plant growth niedia was higher in the nitrate fertilizer treatment than the ammonium and other fertilizer forms. NO3--N application increased NRA in plant, but NH4+-N decreased NRA in plant. Harvesting date and different fertilizer doses increased NRA while NH4+-N decreased plant nitrate uptake. There was a significant relationship between NRA and fertilizer types.

  17. Calculus of One and More Variables with Maple

    Science.gov (United States)

    Samkova, Libuse

    2012-01-01

    This is a guide to using Maple in teaching fundamental calculus of one, two and three variables (limits, derivatives, integrals, etc.), also suitable for Maple beginners. It outlines one of the ways to effective use of computers in the teaching process. It scans advantages and disadvantages of using Maple in relation to students and teacher. The…

  18. 英译汉原文:Leafing Through Maple Lore

    Institute of Scientific and Technical Information of China (English)

    Bill Casselman

    2005-01-01

    @@ The maple smoke of autumn bonfires is incense to Canadians. Bestowing aroma for the nose, chroma for the eye, sweetness for the spring tongue, the sugar maple prompts this sharing of a favourite myth and an original etymology of the word maple.

  19. DEVELOPMENT OF MAPLE IN TRAINING HIGHER MATHEMATICS

    Directory of Open Access Journals (Sweden)

    Volodymyr M. Mykhalevych

    2011-03-01

    Full Text Available The relevance of the material presented in this paper due to the need to develop and implement new information technologies in teaching higher mathematics with the use of systems of symbolic mathematics. Brief analysis of the Maple and Mathematica is given. The basic results of authors on working out of a training complex on higher mathematics are given. The complex was created in an environment of symbolic mathematics Maple. Procedure simulators, which give the whole process of model solutions of mathematical problems are a major element of the complex. The results of such procedures for typical problems from different sections of higher mathematics in accordance with the program for technical universities are represented. Questions the benefits and methods of using such programs, in particular those related to deficits of licensed copies of Maple was touched.

  20. Multi-walled Сarbon Nanotubes Penetrate into Plant Cells and Affect the Growth of Onobrychis arenaria Seedlings.

    Science.gov (United States)

    Smirnova, E A; Gusev, A A; Zaitseva, O N; Lazareva, E M; Onishchenko, G E; Kuznetsova, E V; Tkachev, A G; Feofanov, A V; Kirpichnikov, M P

    2011-01-01

    Engineered nanoparticles (ENPs) are now being used in many sectors of industry; however, the impact of ENPs on the environment still requires further study, since their use, recycling, and accidental spill can result in the accumulation of nanoparticles in the atmosphere, soil, and water. Plants are an integral part of ecosystems; hence their interaction with ENPs is inevitable. It is important to understand the consequences of this interaction and assess its potential effects. The present research is focused on studying the effects of the industrial material Taunit, containing multi-walled carbon nanotubes (MWNTs), on plants, and testing of its ability to penetrate into plant cells and tissues. Taunit has been found to stimulate the growth of roots and stems and cause an increase in peroxidase activity inOnobrychis arenariaseedlings. Peroxidase activity increases with decreasing concentration of Taunit from 1,000 to 100 mg/l. MWNTs from Taunit were detected in the cells and tissues of seedling roots and leaves, implying the ability of MWNTs to penetrate into roots and accumulate there, as well as their ability to be transported into seedling leaves. Thus, the changes in the physiological parameters of plants are associated not only with MWNT adsorption on the root surface, as previously believed, but also with their penetration, uptake and accumulation in the plant cells and tissues.

  1. Root system architecture and receptivity to mycorrhizal infection in seedlings of Cedrus atlantica as affected by nitrogen source and concentration.

    Science.gov (United States)

    Boukcim, H; Pages, L; Plassard, C; Mousain, D

    2001-02-01

    Effects of nitrogen (N) source and concentration on root system architecture and receptivity to mycorrhizal infection were studied in seedlings of Atlas cedar (Cedrus atlantica Manetti) grown in root observation boxes in a controlled-environment chamber. Nitrogen was supplied in a solution containing either NO3-; or NH4+ at a concentration of either 0.25 or 5.0 mM. Root extension was recorded twice weekly by tracing the roots growing in contact with the transparent face of the root observation box. Among treatments, lateral root production and branching density were greatest with 5.0 mM NO3-. Inoculation with mycelium of Tricholoma cedrorum Malencon was carried out 3 months after the start of the N treatments. The highest percentage of mycorrhizal roots, and the greatest amounts of living mycelium (estimated by the ergosterol assay) were observed in the NO3- treatments. Differences in root branching density among the N treatments were insufficient to explain the observed differences among treatments in the extent of mycorrhizal infection of seedlings.

  2. Symbolic computation of Appell polynomials using Maple

    Directory of Open Access Journals (Sweden)

    H. Alkahby

    2001-07-01

    Full Text Available This work focuses on the symbolic computation of Appell polynomials using the computer algebra system Maple. After describing the traditional approach of constructing Appell polynomials, the paper examines the operator method of constructing the same Appell polynomials. The operator approach enables us to express the Appell polynomial as Bessel function whose coefficients are Euler and Bernuolli numbers. We have also constructed algorithms using Maple to compute Appell polynomials based on the methods we have described. The achievement is the construction of Appell polynomials for any function of bounded variation.

  3. Contrasting nutritional acclimation of sugar maple (Acer saccharum Marsh. and red maple (Acer rubrum L. to increasing conifers and soil acidity as demonstrated by foliar nutrient balances

    Directory of Open Access Journals (Sweden)

    Alexandre Collin

    2016-07-01

    Full Text Available Sugar maple (Acer saccharum Marshall, SM is believed to be more sensitive to acidic and nutrient-poor soils associated with conifer-dominated stands than red maple (Acer rubrum L., RM. Greater foliar nutrient use efficiency (FNUE of RM is likely the cause for this difference. In the context of climate change, this greater FNUE could be key in favouring northward migration of RM over SM. We used the concept of foliar nutrient balances to study the nutrition of SM and RM seedlings along an increasing gradient in forest floor acidity conditioned by increasing proportions of conifers (pH values ranging from 4.39 under hardwoods, to 4.29 under mixed hardwood-conifer stands and 4.05 under conifer-dominated stands. Nutrients were subjected to isometric log-ratio (ilr transformation, which views the leaf as one closed system and considers interactions between nutrients. The ilr method eliminates numerical biases and weak statistical inferences based on raw or operationally’’ log-transformed data. We analyzed foliar nutrients of SM and RM seedlings and found that the [Ca,Mg,K|P,N] and [Ca,Mg|K] balances of SM seedlings were significantly different among soil acidity levels, whereas they did not vary for RM seedlings. For SM seedlings, these differences among soil acidity levels were due to a significant decrease in foliar Ca and Mg concentrations with increasing forest floor acidity. Similar differences in foliar balances were also found between healthy and declining SM stands estimated from literature values. Conversely, foliar balances of RM seedlings did not differ among soil acidity levels, even though untransformed foliar nutrient concentrations were significantly different. This result highlights the importance of using ilr transformation, since it provides more sensitive results than standard testing of untransformed nutrient concentrations. The lower nutrient requirements of RM and its greater capacity to maintain nutrient equilibrium are

  4. Sugar maple growth in relation to nutrition and stress in the northeastern United States.

    Science.gov (United States)

    Long, Robert P; Horsley, Stephen B; Hallett, Richard A; Bailey, Scott W

    2009-09-01

    Sugar maple, Acer saccharum, decline disease is incited by multiple disturbance factors when imbalanced calcium (Ca), magnesium (Mg), and manganese (Mn) act as predisposing stressors. Our objective in this study was to determine whether factors affecting sugar maple health also affect growth as estimated by basal area increment (BAI). We used 76 northern hardwood stands in northern Pennsylvania, New York, Vermont, and New Hampshire, USA, and found that sugar maple growth was positively related to foliar concentrations of Ca and Mg and stand level estimates of sugar maple crown health during a high stress period from 1987 to 1996. Foliar nutrient threshold values for Ca, Mg, and Mn were used to analyze long-term BAI trends from 1937 to 1996. Significant (P maples sampled in the 1990s had decreased growth in the 1970s, 10-20 years in advance of the 1980s and 1990s decline episode in Pennsylvania. Even apparently healthy stands that had no defoliation, but had below-threshold amounts of Ca or Mg and above-threshold Mn (from foliage samples taken in the mid 1990s), had decreasing growth by the 1970s. Co-occurring black cherry, Prunus serotina, in a subset of the Pennsylvania and New York stands, showed opposite growth responses with greater growth in stands with below-threshold Ca and Mg compared with above-threshold stands. Sugar maple growing on sites with the highest concentrations of foliar Ca and Mg show a general increase in growth from 1937 to 1996 while other stands with lower Ca and Mg concentrations show a stable or decreasing growth trend. We conclude that acid deposition induced changes in soil nutrient status that crossed a threshold necessary to sustain sugar maple growth during the 1970s on some sites. While nutrition of these elements has not been considered in forest management decisions, our research shows species specific responses to Ca and Mg that may reduce health and growth of sugar maple or change species composition, if not addressed.

  5. Partial differential equations & boundary value problems with Maple

    CERN Document Server

    Articolo, George A

    2009-01-01

    Partial Differential Equations and Boundary Value Problems with Maple presents all of the material normally covered in a standard course on partial differential equations, while focusing on the natural union between this material and the powerful computational software, Maple. The Maple commands are so intuitive and easy to learn, students can learn what they need to know about the software in a matter of hours- an investment that provides substantial returns. Maple''s animation capabilities allow students and practitioners to see real-time displays of the solutions of partial differential equations.  Maple files can be found on the books website. Ancillary list: Maple files- http://www.elsevierdirect.com/companion.jsp?ISBN=9780123747327  Provides a quick overview of the software w/simple commands needed to get startedIncludes review material on linear algebra and Ordinary Differential equations, and their contribution in solving partial differential equationsIncorporates an early introduction to Sturm-L...

  6. Engineering Mathematics Assessment Using "MapleTA"

    Science.gov (United States)

    Jones, Ian S.

    2008-01-01

    The assessment of degree level engineering mathematics students using the computer-aided assessment package MapleTA is discussed. Experience of academic and practical issues for both online coursework and examination assessments is presented, hopefully benefiting other academics in this novel area of activity. (Contains 6 figures and 1 table.)

  7. Building improved models of sugar maple mortality

    Science.gov (United States)

    Charles H. Perry; Patrick L. Zimmerman

    2012-01-01

    The decline of sugar maple (Acer saccharum Marsh.) in the northern United States is causing concern, and several studies have identified soil properties that are linked to the observation of dead/dying trees. Unfortunately, the sample of trees supporting these studies is purposive in nature; soil properties are assessed only on those plots where dead...

  8. Applications of Maple To Algebraic Cryptography.

    Science.gov (United States)

    Sigmon, Neil P.

    1997-01-01

    Demonstrates the use of technology to enhance the appreciation of applications involving abstract algebra. The symbolic manipulator Maple can perform computations required for a linear cryptosystem. One major benefit of this process is that students can encipher and decipher messages using a linear cryptosystem without becoming confused and…

  9. Applications of Maple To Algebraic Cryptography.

    Science.gov (United States)

    Sigmon, Neil P.

    1997-01-01

    Demonstrates the use of technology to enhance the appreciation of applications involving abstract algebra. The symbolic manipulator Maple can perform computations required for a linear cryptosystem. One major benefit of this process is that students can encipher and decipher messages using a linear cryptosystem without becoming confused and…

  10. Experimental sand burial affects seedling survivorship, morphological traits, and biomass allocation of Ulmus pumila var. sabulosa in the Horqin Sandy Land, China

    Science.gov (United States)

    Tang, Jiao; Busso, Carlos Alberto; Jiang, Deming; Musa, Ala; Wu, Dafu; Wang, Yongcui; Miao, Chunping

    2016-07-01

    As a native tree species, Ulmus pumila var. sabulosa (sandy elm) is widely distributed in the Horqin Sandy Land, China. However, seedlings of this species have to withstand various depths of sand burial after emergence because of increasing soil degradation, which is mainly caused by overgrazing, climate change, and wind erosion. An experiment was conducted to evaluate the changes in its survivorship, morphological traits, and biomass allocation when seedlings were buried at different burial depths: unburied controls and seedlings buried vertically up to 33, 67, 100, or 133 % of their initial mean seedling height. The results showed that partial sand burial treatments (i.e., less than 67 % burial) did not reduce seedling survivorship, which still reached 100 %. However, seedling mortality increased when sand burial was equal to or greater than 100 %. In comparison with the control treatment, seedling height and stem diameter increased at least by 6 and 14 % with partial burial, respectively. In the meantime, seedling taproot length, total biomass, and relative mass growth rates were at least enhanced by 10, 15.6, and 27.6 %, respectively, with the partial sand burial treatment. Furthermore, sand burial decreased total leaf area and changed biomass allocation in seedlings, partitioning more biomass to aboveground organs (e.g., leaves) and less to belowground parts (roots). Complete sand burial after seedling emergence inhibited its re-emergence and growth, even leading to death. Our findings indicated that seedlings of sandy elm showed some resistance to partial sand burial and were adapted to sandy environments from an evolutionary perspective. The negative effect of excessive sand burial after seedling emergence might help in understanding failures in recruitments of sparse elm in the study region.

  11. Lanthanum Affects Bell Pepper Seedling Quality Depending on the Genotype and Time of Exposure by Differentially Modifying Plant Height, Stem Diameter and Concentrations of Chlorophylls, Sugars, Amino Acids, and Proteins.

    Science.gov (United States)

    García-Jiménez, Atonaltzin; Gómez-Merino, Fernando C; Tejeda-Sartorius, Olga; Trejo-Téllez, Libia I

    2017-01-01

    Lanthanum (La) is considered a beneficial element, capable of inducing hormesis. Hormesis is a dose-response relationship phenomenon characterized by low-dose stimulation and high-dose inhibition. Herein we tested the effect of 0 and 10 μM La on growth and biomolecule concentrations of seedlings of four sweet bell pepper (Capsicum annuum L.) varieties, namely Sven, Sympathy, Yolo Wonder, and Zidenka. Seedling evaluations were performed 15 and 30 days after treatment applications (dat) under hydroponic greenhouse conditions. Seedling height was significantly increased by La, growing 20% taller in Yolo Wonder plants, in comparison to the control. Similarly, La significantly enhanced shoot diameter, with increases of 9 and 9.8% in measurements performed 15 and 30 dat, respectively, as compared to the control. Likewise, La-treated seedlings had a higher number of flower buds than the control. An increase in the number of leaves because of La application was observed in Yolo Wonder seedlings, both 15 and 30 dat, while leaf area was augmented in this variety only 30 dat. Nevertheless, La did not affect dry biomass accumulation. La effects on biomolecule concentration were differential over time. In all varieties, La stimulated the biosynthesis of chlorophyll a, b and total 15 dat, though 30 dat only the varieties Sympathy and Yolo Wonder showed enhanced concentrations of these molecules because of La. Total soluble sugars increased in La-treated seedlings 30 dat. Interestingly, while most varieties exposed to La showed a reduction in amino acid concentration 15 dat, the opposite trend was observed 30 dat. Importantly, in all varieties evaluated, La stimulated soluble protein concentration 30 dat. It is important to note that while chlorophyll concentrations increased in all varieties exposed to La, both 15 and 30 dat, those of soluble sugars and proteins consistently increased only 30 dat, but not 15 dat. Our results confirm that La may improve seedling quality by

  12. Interannual and spatial variability of maple syrup yield as related to climatic factors

    Directory of Open Access Journals (Sweden)

    Louis Duchesne

    2014-06-01

    Full Text Available Sugar maple syrup production is an important economic activity for eastern Canada and the northeastern United States. Since annual variations in syrup yield have been related to climate, there are concerns about the impacts of climatic change on the industry in the upcoming decades. Although the temporal variability of syrup yield has been studied for specific sites on different time scales or for large regions, a model capable of accounting for both temporal and regional differences in yield is still lacking. In the present study, we studied the factors responsible for interregional and interannual variability in maple syrup yield over the 2001–2012 period, by combining the data from 8 Quebec regions (Canada and 10 U.S. states. The resulting model explained 44.5% of the variability in yield. It includes the effect of climatic conditions that precede the sapflow season (variables from the previous growing season and winter, the effect of climatic conditions during the current sapflow season, and terms accounting for intercountry and temporal variability. Optimal conditions for maple syrup production appear to be spatially restricted by less favourable climate conditions occurring during the growing season in the north, and in the south, by the warmer winter and earlier spring conditions. This suggests that climate change may favor maple syrup production northwards, while southern regions are more likely to be negatively affected by adverse spring conditions.

  13. Geometry of curves and surfaces with Maple

    CERN Document Server

    Rovenski, Vladimir

    2000-01-01

    This concise text on geometry with computer modeling presents some elementary methods for analytical modeling and visualization of curves and surfaces. The author systematically examines such powerful tools as 2-D and 3-D animation of geometric images, transformations, shadows, and colors, and then further studies more complex problems in differential geometry. Well-illustrated with more than 350 figures---reproducible using Maple programs in the book---the work is devoted to three main areas: curves, surfaces, and polyhedra. Pedagogical benefits can be found in the large number of Maple programs, some of which are analogous to C++ programs, including those for splines and fractals. To avoid tedious typing, readers will be able to download many of the programs from the Birkhauser web site. Aimed at a broad audience of students, instructors of mathematics, computer scientists, and engineers who have knowledge of analytical geometry, i.e., method of coordinates, this text will be an excellent classroom resource...

  14. Dynamical systems with applications using Maple

    CERN Document Server

    Lynch, Stephen

    2001-01-01

    "The text treats a remarkable spectrum of topics and has a little for everyone. It can serve as an introduction to many of the topics of dynamical systems, and will help even the most jaded reader, such as this reviewer, enjoy some of the interactive aspects of studying dynamics using Maple." —UK Nonlinear News (Review of First Edition) "The book will be useful for all kinds of dynamical systems courses…. [It] shows the power of using a computer algebra program to study dynamical systems, and, by giving so many worked examples, provides ample opportunity for experiments. … [It] is well written and a pleasure to read, which is helped by its attention to historical background." —Mathematical Reviews (Review of First Edition) Since the first edition of this book was published in 2001, Maple™ has evolved from Maple V into Maple 13. Accordingly, this new edition has been thoroughly updated and expanded to include more applications, examples, and exercises, all with solutions; two new chapters on neural n...

  15. Structural characterization of MAPLE deposited lipase biofilm

    Energy Technology Data Exchange (ETDEWEB)

    Aronne, Antonio [Department of Chemical Engineering, Materials and Industrial Production, Università degli Studi di Napoli Federico II, Piazzale V. Tecchio 80, 80125 Napoli (Italy); Ausanio, Giovanni; Bloisi, Francesco [CNR-SPIN and Department of Physics, Università degli Studi di Napoli Federico II, Piazzale V. Tecchio 80, 80125 Napoli (Italy); Calabria, Raffaela [Istituto Motori-CNR, via G. Marconi 8, 80125 Napoli (Italy); Califano, Valeria, E-mail: v.califano@im.cnr.it [Istituto Motori-CNR, via G. Marconi 8, 80125 Napoli (Italy); Fanelli, Esther [Department of Chemical Engineering, Materials and Industrial Production, Università degli Studi di Napoli Federico II, Piazzale V. Tecchio 80, 80125 Napoli (Italy); Massoli, Patrizio [Istituto Motori-CNR, via G. Marconi 8, 80125 Napoli (Italy); Vicari, Luciano R.M. [CNR-SPIN and Department of Physics, Università degli Studi di Napoli Federico II, Piazzale V. Tecchio 80, 80125 Napoli (Italy)

    2014-11-30

    Highlights: • Lipase from Candida Rugosa was deposited by Matrix Assisted Pulsed Laser Evaporation (MAPLE) on KBr pellets, mica and glass substrate. • The deposited film was characterized morphologically and structurally by optical microscopy, SEM and FTIR analysis. • Results of characterization underlined a phenomenon of aggregation taking place. • The aggregation phenomenon was reversible since lipase showed activity in the transesterification reaction between soybean oil and isopropyl alcohol once detached from the substrate. - Abstract: Lipases (triacylglycerol ester hydrolases) are enzymes used in several industrial applications. Enzymes immobilization can be used to address key issues limiting widespread application at industrial level. Immobilization efficiency is related to the ability to preserve the native conformation of the enzyme. MAPLE (Matrix Assisted Pulsed Laser Evaporation) technique, a laser deposition procedure for treating organic/polymeric/biomaterials, was applied for the deposition of lipase enzyme in an ice matrix, using near infrared laser radiation. Microscopy analysis showed that the deposition occurred in micrometric and submicrometric clusters with a wide size distribution. AFM imaging showed that inter-cluster regions are uniformly covered with smaller aggregates of nanometric size. Fourier transform infrared spectroscopy was used for both recognizing the deposited material and analyzing its secondary structure. Results showed that the protein underwent reversible self-association during the deposition process. Actually, preliminary tests of MAPLE deposited lipase used for soybean oil transesterification with isopropyl alcohol followed by gas chromatography–mass spectrometry gave results consistent with undamaged deposition of lipase.

  16. Thin films growth parameters in MAPLE; application to fibrinogen

    Energy Technology Data Exchange (ETDEWEB)

    Jelinek, M [Institute of Physics ASCR, Na Slovance 2, 182 21Prague 8 (Czech Republic); Cristescu, R [Institute of Physics ASCR, Na Slovance 2, 182 21Prague 8 (Czech Republic); Kocourek, T [Institute of Physics ASCR, Na Slovance 2, 182 21Prague 8 (Czech Republic); Vorlicek, V [Institute of Physics ASCR, Na Slovance 2, 182 21Prague 8 (Czech Republic); Remsa, J [Institute of Physics ASCR, Na Slovance 2, 182 21Prague 8 (Czech Republic); Stamatin, L [Longhin Scarlat Dermato-Venerologic Hospital, Bucharest (Romania); Mihaiescu, D [University of Agriculture Sciences and Veterinary Medicine, 59 Marasti, Bucharest (Romania); Stamatin, I [University of Bucharest, Faculty of Physics, PO Box MG-11, 3Nano-SAE, Bucharest-Magurele (Romania); Mihailescu, I N [National Institute for Laser, Plasma and Radiation Physics, MG-36, RO-77125, Bucharest (Romania); Chrisey, D B [Naval Research Laboratory, Code 6851 Washington, DC 20375 (United States)

    2007-04-15

    Increasingly requirements on the thin film quality of functionalized materials are efficiently met by a novel laser processing technique - Matrix Assisted Pulsed Laser Evaporation (MAPLE). Examples of deposition conditions and main features characteristic to film growth rate of MAPLE-fabricated organic materials are summarized. MAPLE experimental results are compared with ones corresponding to the classical Pulsed Laser Deposition (PLD). In particular, the results of investigation of MAPLE-deposited fibrinogen blood protein thin films using a KrF* excimer laser and characterized by FTIR and Raman spectrometry are reported.

  17. Typological classification and the existing condition of artificially established sycamore maple and Norway maple stands in the protective forest belt

    Directory of Open Access Journals (Sweden)

    Milošević Rajko

    2011-01-01

    Full Text Available The study results on the typological classification of the artificially established sycamore maple and Norway maple stands included in the shelterbelt along the „Belgrade-Zagreb“ highway are presented. The environmental conditions of the sycamore and Norway maple plantation have been typologically defined in specific typological entitities at the ecological level (ecological units. In this context, the specific site conditions were characterised and defined as: a Forest of common oak (Tilio-Quercetum crassiusculae typicum on leached chernozem, b Forest of common oak (Tilio-Quercetum crassiusculae typicum on moderately deep to deep calcareous chernozem, c Forest of common oak (Tilio-Quercetum crassiusculae typicum on shallow to moderately deep calcareous chernozem. The inter-relationship between sycamore maple and Norway maple regarding the ecological and coenological optimum differs within the above ecological units. The diversity reflects the sycamore and Norway maple bioecology and the site typology of the particular ecological units.

  18. Typological classification and the existing condition of artificially established sycamore maple and Norway maple stands in the protective forest belt

    OpenAIRE

    Milošević Rajko

    2011-01-01

    The study results on the typological classification of the artificially established sycamore maple and Norway maple stands included in the shelterbelt along the „Belgrade-Zagreb“ highway are presented. The environmental conditions of the sycamore and Norway maple plantation have been typologically defined in specific typological entitities at the ecological level (ecological units). In this context, the specific site conditions were characterised and define...

  19. Competition for nitrogen between Fagus sylvatica and Acer pseudoplatanus seedlings depends on soil nitrogen availability

    Directory of Open Access Journals (Sweden)

    Xiuyuan eLi

    2015-04-01

    Full Text Available Competition for nitrogen (N, particularly in resource-limited habitats, might be avoided by different N acquisition strategies of plants. In our study, we investigated whether slow-growing European beech and fast-growing sycamore maple seedlings avoid competition for growth-limiting N by different N uptake patterns and the potential alteration by soil N availability in a microcosm experiment. We quantified growth and biomass indices, 15N uptake capacity and N pools in the fine roots. Overall, growth indices, N acquisition and N pools in the fine roots were influenced by species-specific competition depending on soil N availability. With interspecific competition, growth of sycamore maple reduced regardless of soil N supply, whereas beech only showed reduced growth when N was limited. Both species responded to interspecific competition by alteration of N pools in the fine roots; however, sycamore maple showed a stronger response compared to beech for almost all N pools in roots, except for structural N at low soil N availability. Beech generally preferred organic N acquisition while sycamore maple took up more inorganic N. Furthermore, with interspecific competition, beech had an enhanced organic N uptake capacity, while in sycamore maple inorganic N uptake capacity was impaired by the presence of beech. Although sycamore maple could tolerate the suboptimal conditions at the cost of reduced growth, our study indicates its reduced competitive ability for N compared to beech.

  20. Seedling mycorrhiza

    DEFF Research Database (Denmark)

    Rasmussen, Hanne Nina; Rasmussen, Finn N.

    2014-01-01

    mycobionts suggest a derivation from a pathogenic relationship, and sister group comparison offers little support for derivation from other mycorrhizal relationships. A combination of in situ sowings and molecular identification of seedling mycobionts has established that a broad range of fungi besides...

  1. Phytochemical analysis of Jatropha curcas L. during different seasons and developmental stages and seedling growth of wheat (Triticum aestivum L) as affected by extracts/leachates of Jatropha curcas L.

    Science.gov (United States)

    Tomar, Nisha Singh; Sharma, Malini; Agarwal, R M

    2015-01-01

    Jatropha curcas shows invasive characters and is a significant source of many phytochemicals with varying biological activities. Different plant parts of Jatropha curcas L exhibited variation in their phytochemical constituents. Leaves and ovary walls were found to contain higher contents of total phenols, tannins and phytic acid whereas free amino acids were greater in leaves. Young leaves of Jatropha show greater contents of all these metabolites. Further, plants exhibit seasonal differences as leaves collected during summer (May-June) have greater accumulation of total phenols, tannins and free amino acids however, phytic acid was more during rainy season. Leachates and extracts in their higher concentrations adversely affected the germination and growth of wheat seedlings however, lower concentrations were more or less stimulatory. These treatments not only decreased the length, fresh and dry weight of seedlings but also affected the chlorophyll contents and activity of enzymes such as nitrate reductase, aminotransferases in wheat seedlings however, the activity of superoxide dismutase and ascorbate peroxidases increased. Experiments indicate harmful allelopathic effects of Jatropha leachates /extracts on wheat seedlings, hence further experimentation and analysis is recommended before continued plantation of Jatropha particularly on fertile soils. However. Growth of Jatropha plants on saline soils and their potential for accumulating sodium, potassium and chloride are the attributes suggesting the possibility of use of Jatropha plants in improving saline soils.

  2. Monitoring the Health of Sugar Maple, "Acer Saccharum"

    Science.gov (United States)

    Carlson, Martha

    2013-01-01

    The sugar maple, "Acer saccharum," is projected to decline and die in 88 to 100 percent of its current range in the United States. An iconic symbol of the northeastern temperate forest and a dominant species in this forest, the sugar maple is identified as the most sensitive tree in its ecosystem to rising temperatures and a warming…

  3. Monitoring the Health of Sugar Maple, "Acer Saccharum"

    Science.gov (United States)

    Carlson, Martha

    2013-01-01

    The sugar maple, "Acer saccharum," is projected to decline and die in 88 to 100 percent of its current range in the United States. An iconic symbol of the northeastern temperate forest and a dominant species in this forest, the sugar maple is identified as the most sensitive tree in its ecosystem to rising temperatures and a warming…

  4. Detection of Inulin, a Prebiotic Polysaccharide, in Maple Syrup.

    Science.gov (United States)

    Sun, Jiadong; Ma, Hang; Seeram, Navindra P; Rowley, David C

    2016-09-28

    Maple syrup is a widely consumed plant-derived natural sweetener produced by concentrating xylem sap collected from certain maple (Acer) species. During thermal evaporation of water, natural phytochemical components are concentrated in maple syrup. The polymeric components from maple syrup were isolated by ethanol precipitation, dialysis, and anion exchange chromatography and structurally characterized by glycosyl composition analysis, glycosyl linkage analysis, and nuclear magnetic resonance spectroscopy. Among the maple syrup polysaccharides, one neutral polysaccharide was characterized as inulin with a broad molecular weight distribution, representing the first isolation of this prebiotic carbohydrate from a xylem sap. In addition, two acidic polysaccharides with structural similarity were identified as arabinogalactans derived from rhamnogalacturonan type I pectic polysaccharides.

  5. Auxin polar transport of etiolated epicotyls of ageotropum pea seedlings is not affected by gravistimulation: Relevance to automorphosis-like growth and development

    Science.gov (United States)

    Miyamoto, K.; Hoshino, T.; Takahashi, Y.; Ueda, J.

    Both true microgravity conditions in space STS-95 space experiment and simulated ones on a three-dimensional 3-D clinostat have been demonstrated to induce automorphosis in etiolated pea Pisum sativum L cv Alaska seedlings represented as epicotyl bending as well as changes in root growth direction and inhibition of hook formation and to alter the activities of auxin polar transport of epicotyls The fact that the application of inhibitors of auxin polar transport phenocopied automorphosis together with the result of detail kinetic analyses of epicotyl bending on the 3-D clinostat suggests that automorphosis of etiolated pea epicotyls is due to suppression of a negative gravitropic response on 1 g conditions and graviresponse of etiolated pea seedlings under 1 g conditions requires normal activities of auxin polar transport To study the role of auxin polar transport in graviresponse in early growth stage of etiolated pea seedlings effect of gravistimulation on auxin polar transport in epicotyls of Alaska pea seedlings was studied in comparison with that of the agravitropic pea mutant ageotropum seedlings Dry pea seeds whose embryo axes were set in a horizontal position referred to as horizontal position or an inclinational one to the gravity vector referred to as inclinational position allowed to germinate and grow in the dark for 2 5 days Epicotyls of etiolated Alaska pea seedlings grown under horizontal position showed negative gravitropisum due to relatively larger elongation in the proximal side to the cotyledons

  6. Growth and yield of rice as affected by transplanting dates and seedlings per hill under high temperature of Dera Ismail Khan, Pakistan

    Institute of Scientific and Technical Information of China (English)

    BALOCH Mohammad Safdar; AWAN Inayat Ullah; HASSAN Gul

    2006-01-01

    Studies were initiated for two consecutive years to find out the effect of time of transplanting and seedlings hill-1 on the productivity of rice in Dera Ismail Khan district of North West Frontier Province (NWFP), Pakistan. The experiment was laid out in a randomized complete block design with split plot arrangements. Main plots consisted of four transplanting dates viz. 20th and 27th of June and 4th and 1 lth of July while sub-plots contained 1, 2, 3 or 4 seedlings hill-1. Among transplanting dates, June 20th planted crop gave highest paddy yield and net return with 1 seedling hill-1. It explains that the use of more seedlings hill-1 not only adds to cost but is also a mere wastage of natural resources. Based on research findings, we conclude that the use of 1 seedling hill-1 is most appropriate for timely sowing otherwise 4 seedlings hill-1 should be used to compensate for the yield gap in late transplanted rice.

  7. A Comparison of Invasive Acer platanoides and Native A. saccharum First-Year Seedlings: Growth, Biomass Distribution and the Influence of Ecological Factors in a Forest Understory

    Directory of Open Access Journals (Sweden)

    Jacques Brisson

    2012-05-01

    Full Text Available Invasive shade tolerant species can have profound and long-lasting detrimental effects even on previously undisturbed forests. In North American forests, the invasive Acer platanoides is capable of dominating the understory where it could displace the native Acer saccharum. To understand the relative importance of various ecological factors in a forest understory on their establishment, we transplanted A. platanoides and A. saccharum seedlings in an urban sugar maple forest understory and their growth and survival were compared over a growing season. Seedlings did not differ in height, but biomass growth and assimilation rates were twice as high for the invasive species. Ecological variables accounted for only 23–24% of variation in growth. Seedlings of A. platanoides appeared to capture light more efficiently, with over 150% greater foliage biomass and surface area. A. saccharum seedlings were more negatively affected by herbivory. The more robust A. platanoides seedlings presented characteristics that could allow them to better grow and survive in shaded understories than their native congeners.

  8. Maple syrup urine disease: mechanisms and management.

    Science.gov (United States)

    Blackburn, Patrick R; Gass, Jennifer M; Vairo, Filippo Pinto E; Farnham, Kristen M; Atwal, Herjot K; Macklin, Sarah; Klee, Eric W; Atwal, Paldeep S

    2017-01-01

    Maple syrup urine disease (MSUD) is an inborn error of metabolism caused by defects in the branched-chain α-ketoacid dehydrogenase complex, which results in elevations of the branched-chain amino acids (BCAAs) in plasma, α-ketoacids in urine, and production of the pathognomonic disease marker, alloisoleucine. The disorder varies in severity and the clinical spectrum is quite broad with five recognized clinical variants that have no known association with genotype. The classic presentation occurs in the neonatal period with developmental delay, failure to thrive, feeding difficulties, and maple syrup odor in the cerumen and urine, and can lead to irreversible neurological complications, including stereotypical movements, metabolic decompensation, and death if left untreated. Treatment consists of dietary restriction of BCAAs and close metabolic monitoring. Clinical outcomes are generally good in patients where treatment is initiated early. Newborn screening for MSUD is now commonplace in the United States and is included on the Recommended Uniform Screening Panel (RUSP). We review this disorder including its presentation, screening and clinical diagnosis, treatment, and other relevant aspects pertaining to the care of patients.

  9. Laser transfer of biomaterials: Matrix-assisted pulsed laser evaporation (MAPLE) and MAPLE Direct Write

    Science.gov (United States)

    Wu, P. K.; Ringeisen, B. R.; Krizman, D. B.; Frondoza, C. G.; Brooks, M.; Bubb, D. M.; Auyeung, R. C. Y.; Piqué, A.; Spargo, B.; McGill, R. A.; Chrisey, D. B.

    2003-04-01

    Two techniques for transferring biomaterial using a pulsed laser beam were developed: matrix-assisted pulsed laser evaporation (MAPLE) and MAPLE direct write (MDW). MAPLE is a large-area vacuum based technique suitable for coatings, i.e., antibiofouling, and MDW is a localized deposition technique capable of fast prototyping of devices, i.e., protein or tissue arrays. Both techniques have demonstrated the capability of transferring large (mol wt>100 kDa) molecules in different forms, e.g., liquid and gel, and preserving their functions. They can deposit patterned films with spatial accuracy and resolution of tens of μm and layering on a variety of substrate materials and geometries. MDW can dispense volumes less than 100 pl, transfer solid tissues, fabricate a complete device, and is computed aided design/computer aided manufacturing compatible. They are noncontact techniques and can be integrated with other sterile processes. These attributes are substantiated by films and arrays of biomaterials, e.g., polymers, enzymes, proteins, eucaryotic cells, and tissue, and a dopamine sensor. These examples, the instrumentation, basic mechanisms, a comparison with other techniques, and future developments are discussed.

  10. NPK and flavonoids affecting insect populations in Dimorphandra mollis seedlings=NPK e flavonoides afetando populações de insetos em mudas de Dimorphandra mollis

    Directory of Open Access Journals (Sweden)

    Lourdes Silva Figueiredo

    2012-01-01

    Full Text Available The study evaluated the influence of different levels of nitrogen (N, phosphorus (P and potassium (K, and flavonoids on the population of insects in Dimorphandra mollis Benth (Leguminosae seedlings. The treatments associated with the highest level of attacks by Frankliniella schulzei (Trybon (Thysanoptera: Thripidae were 600 mg dm-3 of P and 50 mg dm-3 of K. The highest level of attacks by Coccidae occurred for 300 of P and 150 and 250 mg dm-3 of K. The last two treatments also exhibited the highest level of attacks by Pseudococcidae. On the other hand, the control exhibited higher levels of flavonoids and a lower level of insect attacks. We observed a small positive effect of N levels on attack by F. schulzei. The levels of N, P and K negatively affected the levels of flavonoids in the leaves of D. mollis. We detected no significant effects of flavonoid levels on the populations of Coccidae, Pseudoccocidae and F. schulzei. Higher numbers of Coccidae and Pseudococcidae were observed in the abaxial face of apical leaves. However, higher numbers of F. schulzei were observed on the adaxial face at lower heights in the canopy. The preferred treatment for the production of D. mollis seedlings is the control (without fertilization because it showed higher flavonoid levels than other treatments and did not result in higher insect numbers.O estudo avaliou a influência de diferentes níveis de nitrogênio (N, fósforo (P e potássio (K e flavonoides sobre a população de insetos em mudas de Dimorphandra mollis Benth (Leguminosae. Os tratamentos associados com maiores níveis de ataque de Frankliniella schulzei (Trybon (Thysanoptera: Thripidae foram 600 mg dm-3 de P e 50 mg dm-3 de K. Os maiores níveis de ataque de Coccidae ocorreu para 300 de P e 150 e 250 mg dm-3 de K. Os dois últimos tratamentos também exibiram altos níveis de ataque de Pseudococcidae. Por outro lado, o controle exibiu maior nível de flavonoides e menor nível de ataque de

  11. Influence of gelatinous fibers on the shrinkage of silver maple

    Science.gov (United States)

    Donals G. Arganbright; Dwight W. Bensend; Floyd G. Manwiller

    1970-01-01

    The degree of lean was found to have a significant influence on the logitudinal and transverse shrinkage of three soft maple trees. This may be accounted for by differences in the cell wall layer thickness and fibril angle.

  12. Nonlinear physics with Maple for scientists and engineers

    CERN Document Server

    Enns, Richard H

    1997-01-01

    Philosophy of the Text This text has been designed to be an introductory survey of the basic concepts and applied mathematical methods of nonlinear science. Students in engineer­ ing, physics, chemistry, mathematics, computing science, and biology should be able to successfully use this text. In an effort to provide the students with a cutting edge approach to one of the most dynamic, often subtle, complex, and still rapidly evolving, areas of modern research-nonlinear physics-we have made extensive use of the symbolic, numeric, and plotting capabilities of Maple V Release 4 applied to examples from these disciplines. No prior knowledge of Maple or computer programming is assumed, the reader being gently introduced to Maple as an auxiliary tool as the concepts of nonlinear science are developed. The diskette which accompanies the text gives a wide variety of illustrative nonlinear examples solved with Maple. An accompanying laboratory manual of experimental activities keyed to the text allows the student the...

  13. The growth and uptake of Ga and In of rice (Oryza sative L.) seedlings as affected by Ga and In concentrations in hydroponic cultures.

    Science.gov (United States)

    Syu, Chien-Hui; Chien, Po-Hsuan; Huang, Chia-Chen; Jiang, Pei-Yu; Juang, Kai-Wei; Lee, Dar-Yuan

    2017-01-01

    Limited information is available on the effects of gallium (Ga) and indium (In) on the growth of paddy rice. The Ga and In are emerging contaminants and widely used in high-tech industries nowadays. Understanding the toxicity and accumulation of Ga and In by rice plants is important for reducing the effect on rice production and exposure risk to human by rice consumption. Therefore, this study investigates the effect of Ga and In on the growth of rice seedlings and examines the accumulation and distribution of those elements in plant tissues. Hydroponic cultures were conducted in phytotron glasshouse with controlled temperature and relative humidity conditions, and the rice seedlings were treated with different levels of Ga and In in the nutrient solutions. The growth index and the concentrations of Ga and In in roots and shoots of rice seedlings were measured after harvesting. A significant increase in growth index with increasing Ga concentrations in culture solutions (<10mgGaL(-1)) was observed. In addition, the uptake of N, K, Mg, Ca, Mn by rice plants was also enhanced by Ga. However, the growth inhibition were observed while the In concentrations higher than 0.08mgL(-1), and the nutrients accumulated in rice plants were also significant decreased after In treatments. Based on the dose-response curve, we observed that the EC10 (effective concentration resulting in 10% growth inhibition) value for In treatment was 0.17mgL(-1). The results of plant analysis indicated that the roots were the dominant sink of Ga and In in rice seedlings, and it was also found that the capability of translocation of Ga from roots to shoots were higher than In. In addition, it was also found that the PT10 (threshold concentration of phytotoxicity resulting in 10% growth retardation) values based on shoot height and total biomass for In were 15.4 and 10.6μgplant(-1), respectively. The beneficial effects on the plant growth of rice seedlings were found by the addition of Ga in

  14. Sugar Maple Phenology: Anthocyanin Production During Leaf Senescence

    Science.gov (United States)

    Lindgren, E.; Rock, B.

    2007-12-01

    The Northeastern United States is known for its brilliant fall foliage colors. Foliage is responsible for a billion dollar tourism industry. Many comment that past years have not resulted in the amazing color displays seen historically. As sugar maple trees senesce they contribute bright red leaves to the mural of oranges, yellows, and greens. The pigment that produces the red color, anthocyanin, is synthesized in the fall as chlorophyll slowly degrades. Remote sensing data from LandSat during fall senescence can help investigate this event by quantifying color change and intensity. This data can then be compared to ground validation efforts in several study plots. The results will help answer the question, "Why do leaves turn red?" One hypothesis is that this pigment acts as a photoprotectant and screens leaves from UV light. It is possible that an increase in tropospheric ozone has negatively affected fall foliage due to the increased reflection of UV light before it reaches the trees; thereby reducing the leaves need to produce anthocyanin. Another hypothesis is that production of anthocyanin is linked to temperature, with maximum synthesis occurring during cold evenings and moderate days. Temperature changes caused by climate change could also be affecting anthocyanin. Through observing these changes by remote sensing and ground experiments, more can be learned about this phenological stage and why it happens.

  15. Seedling Growth and Phosphorus Cycling in Northern Forest Soils Amended With Biochar and Wood Ash

    Science.gov (United States)

    Noyce, G. L.; Jones, T.; Fulthorpe, R.; Basiliko, N.

    2015-12-01

    Biochar may be a powerful soil amendment to reduce nutrient depletion in North American forests where long-term nitrogen deposition has led to phosphorus (P) limitation, but many effects of biochar in these ecosystems are still unknown. We performed a 12-week growth chamber experiment in which red pine (Pinus resinosa) and sugar maple (Acer saccharum) seedlings were grown in pots with soil from three Ontario forests and varying amounts of sugar maple biochar. Additionally, biochar effects were compared with the effects of wood ash, a forest biomass bioenergy by-product that may also be a beneficial soil amendment in these ecosystems. We assessed plant biomass, soil microbial biomass and phosphatase activity; additional chemical analyses of plant tissue and soils are ongoing. Biochar effects on seedling growth were not consistent across tree species, soil type, and addition rate. For sugar maple seedlings grown in sand and sandy-loam textured soils, biochar additions of 20 t ha-1 significantly (p = 0.03) decreased root biomass by 25 %, and the root-to-shoot ratio correspondingly declined, but this effect was not observed in a silty soil. For red pine seedlings, the same biochar addition rate slightly increased root biomass. Wood ash effects on biomass were similarly variable. For example, in the sandy soil, sugar maple root biomass was significantly lower after application of 16 t ash ha-1, but unchanged by rates of 4 or 40 t ash ha-1. Microbial biomass and soil phosphatase activity also varied by soil type. Phosphatase activity was significantly lower (p = 0.02) in soils with sugar maple compared to red pine, but there were no consistent biochar or ash effects across all soils and species. However, for red pine seedlings grown in silt, biochar significantly (p = 0.04) reduced the phosphatase activity compared to the control and ash soils. Overall, biochar may lessen P-limitation in forested ecosystems, but the suitability of biochar, and wood ash, for increasing P

  16. Monitoring the health of sugar maple, Acer saccharum

    Science.gov (United States)

    Carlson, Martha

    The sugar maple, Acer saccharum, is projected to decline and die in 88 to 100 percent of its current range in the United States. An iconic symbol of the northeastern temperate forest and a dominant species in this forest, the sugar maple is identified as the most sensitive tree in its ecosystem to rising temperatures and a warming climate. This study measures the health of sugar maples on 12 privately owned forests and at three schools in New Hampshire. Laboratory quantitative analyses of leaves, buds and sap as well as qualitative measures of leaf and bud indicate that record high beat in 2012 stressed the sugar maple. The study identifies several laboratory and qualitative tests of health which seem most sensitive and capable of identifying stress early when intervention in forest management or public policy change might counter decline of the species. The study presents evidence of an unusual atmospheric pollution event which defoliated sugar maples in 2010. The study examines the work of citizen scientists in Forest Watch, a K-12 school program in which students monitor the impacts of ozone on white pine, Pinus strobus, another keystone species in New Hampshire's forest. Finally, the study examines three simple measurements of bud, leaf and the tree's acclimation to light. The findings of these tests illuminate findings in the first study. And they present examples of what citizen scientists might contribute to long-term monitoring of maples. A partnership between science and citizens is proposed to begin long-term monitoring and to report on the health of sugar maples.

  17. The role of forest tent caterpillar defoliations and partial harvest in the decline and death of sugar maple.

    Science.gov (United States)

    Hartmann, Henrik; Messier, Christian

    2008-09-01

    Natural and anthropogenic disturbances can act as stresses on tree vigour. According to Manion's conceptual model of tree disease, the initial vigour of trees decreases as a result of predisposing factors that render these trees more vulnerable to severe inciting stresses, stresses that can then cause final vigour decline and subsequent tree death. This tree disease model was tested in sugar maple (Acer saccharum) by assessing the roles of natural and anthropogenic disturbances in tree decline and death. Radial growth data from 377 sugar maple trees that had undergone both defoliations by insects and partial harvest were used to estimate longitudinal survival probabilities as a proxy for tree vigour. Radial growth rates and survival probabilities were compared among trees subjected to different levels of above- and below-ground disturbances, between periods of defoliation and harvest, and between live and dead trees. Manion's tree disease model correctly accounts for vigour decline and tree death in sugar maple; tree growth and vigour were negatively affected by a first defoliation, predisposing these trees to death later during the study period due to a second insect outbreak that initiated a final vigour decline. This decline was accelerated by the partial harvest disturbance in 1993. Even the most severe anthropogenic disturbances from partial harvest did not cause, unlike insect defoliation, any growth or vigour declines in live sugar maple. Natural disturbances acted as predisposing and inciting stresses in tree sugar maple decline and death. Anthropogenic disturbances from a partial harvest at worst accelerated a decline in trees that were already weakened by predisposing and inciting stresses (i.e. repeated insect defoliations). Favourable climatic conditions just before and after the partial harvest may have alleviated possible negative effects on growth resulting from harvesting.

  18. RIR-MAPLE deposition of plasmonic silver nanoparticles

    Science.gov (United States)

    Ge, Wangyao; Hoang, Thang B.; Mikkelsen, Maiken H.; Stiff-Roberts, Adrienne D.

    2016-09-01

    Nanoparticles are being explored in many different applications due to the unique properties offered by quantum effects. To broaden the scope of these applications, the deposition of nanoparticles onto substrates in a simple and controlled way is highly desired. In this study, we use resonant infrared matrix-assisted pulsed laser evaporation (RIR-MAPLE) for the deposition of metallic, silver nanoparticles for plasmonic applications. We find that RIR-MAPLE, a simple and versatile approach, is able to deposit silver nanoparticles as large as 80 nm onto different substrates with good adhesion, regardless of substrate properties. In addition, the nanoparticle surface coverage of the substrates, which result from the random distribution of nanoparticles across the substrate per laser pulse, can be simply and precisely controlled by RIR-MAPLE. Polymer films of poly(3-hexylthiophene-2,5-diyl) (P3HT) are also deposited by RIR-MAPLE on top of the deposited silver nanoparticles in order to demonstrate enhanced absorption due to the localized surface plasmon resonance effect. The reported features of RIR-MAPLE nanoparticle deposition indicate that this tool can enable efficient processing of nanoparticle thin films for applications that require specific substrates or configurations that are not easily achieved using solution-based approaches.

  19. Inhibitory effect of maple syrup on the cell growth and invasion of human colorectal cancer cells

    OpenAIRE

    YAMAMOTO, TETSUSHI; Uemura, Kentaro; MORIYAMA, KAHO; Mitamura, Kuniko; TAGA, ATSUSHI

    2015-01-01

    Maple syrup is a natural sweetener consumed by individuals of all ages throughout the world. Maple syrup contains not only carbohydrates such as sucrose but also various components such as organic acids, amino acids, vitamins and phenolic compounds. Recent studies have shown that these phenolic compounds in maple syrup may possess various activities such as decreasing the blood glucose level and an anticancer effect. In this study, we examined the effect of three types of maple syrup, classif...

  20. Chemical Compositional, Biological, and Safety Studies of a Novel Maple Syrup Derived Extract for Nutraceutical Applications

    OpenAIRE

    Zhang, Yan; Yuan, Tao; Li, Liya; Nahar, Pragati; Slitt, Angela; Seeram, Navindra P.

    2014-01-01

    Maple syrup has nutraceutical potential given the macronutrients (carbohydrates, primarily sucrose), micronutrients (minerals and vitamins), and phytochemicals (primarily phenolics) found in this natural sweetener. We conducted compositional (ash, fiber, carbohydrates, minerals, amino acids, organic acids, vitamins, phytochemicals), in vitro biological, and in vivo safety (animal toxicity) studies on maple syrup extracts (MSX-1 and MSX-2) derived from two declassified maple syrup samples. Alo...

  1. Seed mucilage improves seedling emergence of a sand desert shrub.

    Directory of Open Access Journals (Sweden)

    Xuejun Yang

    Full Text Available The success of seedling establishment of desert plants is determined by seedling emergence response to an unpredictable precipitation regime. Sand burial is a crucial and frequent environmental stress that impacts seedling establishment on sand dunes. However, little is known about the ecological role of seed mucilage in seedling emergence in arid sandy environments. We hypothesized that seed mucilage enhances seedling emergence in a low precipitation regime and under conditions of sand burial. In a greenhouse experiment, two types of Artemisia sphaerocephala achenes (intact and demucilaged were exposed to different combinations of burial depth (0, 5, 10, 20, 40 and 60 mm and irrigation regimes (low, medium and high, which simulated the precipitation amount and frequency in May, June and July in the natural habitat, respectively. Seedling emergence increased with increasing irrigation. It was highest at 5 mm sand burial depth and ceased at burial depths greater than 20 mm in all irrigation regimes. Mucilage significantly enhanced seedling emergence at 0, 5 and 10 mm burial depths in low irrigation, at 0 and 5 mm burial depths in medium irrigation and at 0 and 10 mm burial depths in high irrigation. Seed mucilage also reduced seedling mortality at the shallow sand burial depths. Moreover, mucilage significantly affected seedling emergence time and quiescence and dormancy percentages. Our findings suggest that seed mucilage plays an ecologically important role in successful seedling establishment of A. sphaerocephala by improving seedling emergence and reducing seedling mortality in stressful habitats of the sandy desert environment.

  2. Effects of acidic deposition and soil acidification on sugar maple trees in the Adirondack Mountains, New York

    Science.gov (United States)

    Sullivan, Timothy J.; Lawrence, Gregory B.; Bailey, Scott W.; McDonnell, Todd C.; Beier, Colin M.; Weathers, K.C.; McPherson, G.T.; Bishop, Daniel A.

    2013-01-01

    We documented the effects of acidic atmospheric deposition and soil acidification on the canopy health, basal area increment, and regeneration of sugar maple (SM) trees across the Adirondack region of New York State, in the northeastern United States, where SM are plentiful but not well studied and where widespread depletion of soil calcium (Ca) has been documented. Sugar maple is a dominant canopy species in the Adirondack Mountain ecoregion, and it has a high demand for Ca. Trees in this region growing on soils with poor acid–base chemistry (low exchangeable Ca and % base saturation [BS]) that receive relatively high levels of atmospheric sulfur and nitrogen deposition exhibited a near absence of SM seedling regeneration and lower crown vigor compared with study plots with relatively high exchangeable Ca and BS and lower levels of acidic deposition. Basal area increment averaged over the 20th century was correlated (p acid–base chemistry of the Oa, A, and upper B soil horizons. A lack of Adirondack SM regeneration, reduced canopy condition, and possibly decreased basal area growth over recent decades are associated with low concentrations of nutrient base cations in this region that has undergone soil Ca depletion from acidic deposition.

  3. Effects of acidic deposition and soil acidification on sugar maple trees in the Adirondack Mountains, New York

    Science.gov (United States)

    Sullivan, Timothy J.; Lawrence, Gregory B.; Bailey, Scott W.; McDonnell, Todd C.; Beier, Colin M.; Weathers, K.C.; McPherson, G.T.; Bishop, Daniel A.

    2013-01-01

    We documented the effects of acidic atmospheric deposition and soil acidification on the canopy health, basal area increment, and regeneration of sugar maple (SM) trees across the Adirondack region of New York State, in the northeastern United States, where SM are plentiful but not well studied and where widespread depletion of soil calcium (Ca) has been documented. Sugar maple is a dominant canopy species in the Adirondack Mountain ecoregion, and it has a high demand for Ca. Trees in this region growing on soils with poor acid–base chemistry (low exchangeable Ca and % base saturation [BS]) that receive relatively high levels of atmospheric sulfur and nitrogen deposition exhibited a near absence of SM seedling regeneration and lower crown vigor compared with study plots with relatively high exchangeable Ca and BS and lower levels of acidic deposition. Basal area increment averaged over the 20th century was correlated (p acid–base chemistry of the Oa, A, and upper B soil horizons. A lack of Adirondack SM regeneration, reduced canopy condition, and possibly decreased basal area growth over recent decades are associated with low concentrations of nutrient base cations in this region that has undergone soil Ca depletion from acidic deposition.

  4. Antifungal Activity of Marigold Fungicide Ⅰ and Its Affection to Watermelon Seedling%万寿菊杀菌素Ⅰ抑菌作用及对西瓜幼苗的影响

    Institute of Scientific and Technical Information of China (English)

    范志宏; 郭春绒; 王金胜

    2011-01-01

    研究了万寿菊杀菌素Ⅰ对西瓜枯萎病菌、辣椒枯萎病菌和辣椒疫霉病菌的抑菌作用及对西瓜幼苗的影响.结果表明,万寿菊杀菌素Ⅰ能有效抑制西瓜枯萎病菌、辣椒枯萎病菌和辣椒疫霉病菌.在西瓜枯萎病的主要发病期苗期施用万寿菊杀菌素Ⅰ,能提高西瓜幼苗的POD和SOD活性,并维持CAT活性,有效减轻西瓜枯萎病菌对植株的毒害作用.%Antifungal activity of marigold fungicide Ⅰ and its affection to watermelon seedling was studied.The results showed that marigold fungicide Ⅰ remarkable inhibited mycelial growth of Fusarium oxysporum f.sp.niveum, Fusarium oxysporum and Phytophthpra capsici Len..The marigold fungicide Ⅰ was applied at the main infection period of watermelon Fusarium wilt of seedling, it enhanced the enzymatic activity of superoxide dismutase (SOD)and peroxidase (POD), maintained the CAT activity,and reduced the harm of crude toxin of FON to watermelon plant.

  5. The rhizosphere pH change of Pinus koraiensis seedlings as affected by N sources of different levels and its effect on the availability and uptake of Fe, Mn, Cu and Zn

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Dark brown forest soil was collected from the upper 20 cm soil layer in Changbai Mountain Research Station of Ecosystem, Chinese Academy of Sciences. The soil was amended with two different forms of nitrogen fertilizers: NO3- as Ca(NO3)2, NH4+ as NH4Cl at the concentrations of 50, 100, 200 and 400 mg?kg-1 respectively. The experiment was carried out with 2-yr-old Pinus koraiensis seedlings in pot. The pH change of rhizosphere soil and the contents of available Fe, Mn, Cu, and Zn in soil and leaves were analyzed. The result indicated that the addition of NH4--N decreased the rhizosphere pH value, while the addition of NO3--N increased the rhizosphere pH value in contrast with the control treatment. The direction and extent of the pH change mainly depended on N source and its concentrations applied. The rhizosphere pH change had a remarkable influence on the availability of the micronutrients in the rhizosphere, and thereafter affected the nutrient uptake by the seedlings. The contents of available mineral nutrients had a negative correlation with the pH value in the rhizosphere soil. The contents of available mineral nutrients in leaves were positively correlated to the levels of the available nutrients in the rhizosphere soils.

  6. Postfire seedling dynamics and performance in Pinus halepensis Mill. populations

    Science.gov (United States)

    Daskalakou, Evangelia N.; Thanos, Costas A.

    2010-09-01

    Postfire dynamics of Aleppo pine seedling density, survival and growth were assessed in five burned forests of Attica, Greece (Stamata, Villia, Avlona, Kapandriti and Agios Stefanos) through the establishment of permanent experimental plots. All emerging seedlings were tagged and their survival and growth monitored at regular intervals. Seedling density dynamics show an initial, steep increase (to maximum values 2.9-4.6 seedlings m -2) followed by a gradual decrease that levels off at the second and third postfire year (1.3-3.0 seedlings m -2); similarly, postfire seedling survival more or less stabilised at 30-50%, 2-3 years after fire. On the basis of density and mortality trends as well as relevant bibliographic data, it is predicted that very dense, mature forests (10.000 trees ha -1 or more) will be reinstated within 15-20 years. During the first 5-7 postfire years, seedling/sapling annual height followed linear trends with various yearly rates, ranging mostly between 8 and 15 cm (and 27-30 cm in two exceptional, fast growing cases). Within an individual growth season, seedling height dynamics were found to follow sigmoid curves with growth increment peaks in mid-spring. The time (on a monthly basis) of seedling emergence did not affect seedling growth or survival. On the other hand, for the first time under natural conditions, it has been shown that cotyledon number per seedling, an indirect measure of both seed size and initial photosynthetic capacity, significantly affected seedling survival but not growth. Seedlings bearing a higher number of cotyledons, presumably derived from larger seeds, showed greater survival at the end of the first postfire year than seedlings with fewer cotyledons. A postfire selective pressure, favouring large seed size, is postulated to counteract with a contrasting one, which favours small seed size, expressed during fire-free conditions.

  7. Indledning til Maple for Lineær Algebra

    DEFF Research Database (Denmark)

    Sinclair, Robert

    1999-01-01

    Denne rapport er en undersoegelse af hvordan og hvor vidt Maplesindbyggede kommandoer passer til Jens Eisings bog "Lineaer Algebra" (1997).Maalet er at beskrive, hvordan man bedst kan brugeMaple V Release 5.1i kurset,i viden om mulige problemer, saa man kan undgaa faelder,og svare paa studerendes...

  8. Student Organizations in Canada and Quebec's "Maple Spring"

    Science.gov (United States)

    Bégin-Caouette, Olivier; Jones, Glen A.

    2014-01-01

    This article has two major objectives: to describe the structure of the student movement in Canada and the formal role of students in higher education governance, and to describe and analyze the "Maple Spring," the dramatic mobilization of students in opposition to proposed tuition fee increases in Quebec that eventually led to a…

  9. Indledning til Maple for Lineær Algebra

    DEFF Research Database (Denmark)

    Sinclair, Robert

    1999-01-01

    Denne rapport er en undersoegelse af hvordan og hvor vidt Maplesindbyggede kommandoer passer til Jens Eisings bog "Lineaer Algebra" (1997).Maalet er at beskrive, hvordan man bedst kan brugeMaple V Release 5.1i kurset,i viden om mulige problemer, saa man kan undgaa faelder,og svare paa studerendes...

  10. The pH change in rhizosphere of Pinus koraiensis seedlings as af-fected by different nitrogen sources and its effect on phosphorus availability

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Root mat method described by Kuchenbuch and Jungk was used to study the rhizosphere processes. The experiment was carried out on two years old Pinus koraiensis seedlings. Soil samples collected from the upper 20-cm soil layer in Changbai Mountain were treated with three different forms of nitrogen fertilizers: NO3--N, NH4+-N and NH4NO3. The results showed that the soil pH and available P near the roots were all lower than in the bulk soil in control treatment. NH4+-N application greatly de-creased the soil pH near the roots compared to the control treatment and promoted the absorption of phosphorus, which led to a more remarkable depletion region of available P. On the contrary, the rhizosphere soil pH was higher than in the bulk soil in treatments with NO3--N and retarded the P absorption, which led to a nearly equal available P contents to the bulk soil. In treat-ment with NH4NO3, the rhizosphere soil pH was only a little lower than that in the control treatment and its effects on P absorp-tion is mediate between the treatments with NH4+-N and NO3--N.

  11. Thaxtomin A affects CESA-complex density, expression of cell wall genes, cell wall composition, and causes ectopic lignification in Arabidopsis thaliana seedlings.

    Science.gov (United States)

    Bischoff, Volker; Cookson, Sarah Jane; Wu, Shuang; Scheible, Wolf-Rüdiger

    2009-01-01

    Thaxtomin A, a phytotoxin produced by Streptomyces eubacteria, is suspected to act as a natural cellulose synthesis inhibitor. This view is confirmed by the results obtained from new chemical, molecular, and microscopic analyses of Arabidopsis thaliana seedlings treated with thaxtomin A. Cell wall analysis shows that thaxtomin A reduces crystalline cellulose, and increases pectins and hemicellulose in the cell wall. Treatment with thaxtomin A also changes the expression of genes involved in primary and secondary cellulose synthesis as well as genes associated with pectin metabolism and cell wall remodelling, in a manner nearly identical to isoxaben. In addition, it induces the expression of several defence-related genes and leads to callose deposition. Defects in cellulose synthesis cause ectopic lignification phenotypes in A. thaliana, and it is shown that lignification is also triggered by thaxtomin A, although in a pattern different from isoxaben. Spinning disc confocal microscopy further reveals that thaxtomin A depletes cellulose synthase complexes from the plasma membrane and results in the accumulation of these particles in a small microtubule-associated compartment. The results provide new and clear evidence for thaxtomin A having a strong impact on cellulose synthesis, thus suggesting that this is its primary mode of action.

  12. Acclimation and soil moisture constrain sugar maple root respiration in experimentally warmed soil.

    Science.gov (United States)

    Jarvi, Mickey P; Burton, Andrew J

    2013-09-01

    The response of root respiration to warmer soil can affect ecosystem carbon (C) allocation and the strength of positive feedbacks between climatic warming and soil CO2 efflux. This study sought to determine whether fine-root (respiration in a sugar maple (Acer saccharum Marsh.)-dominated northern hardwood forest would adjust to experimentally warmed soil, reducing C return to the atmosphere at the ecosystem scale to levels lower than that would be expected using an exponential temperature response function. Infrared heating lamps were used to warm the soil (+4 to +5 °C) in a mature sugar maple forest in a fully factorial design, including water additions used to offset the effects of warming-induced dry soil. Fine-root-specific respiration rates, root biomass, root nitrogen (N) concentration, soil temperature and soil moisture were measured from 2009 to 2011, with experimental treatments conducted from late 2010 to 2011. Partial acclimation of fine-root respiration to soil warming occurred, with soil moisture deficit further constraining specific respiration rates in heated plots. Fine-root biomass and N concentration remained unchanged. Over the 2011 growing season, ecosystem root respiration was not significantly greater in warmed soil. This result would not be predicted by models that allow respiration to increase exponentially with temperature and do not directly reduce root respiration in drier soil.

  13. The Study of Seedlings

    NARCIS (Netherlands)

    Jacobs, M.

    1966-01-01

    ”The seedling represents the most critical stage in the life of a tree. Conditions of seeding and germination may be entirely favourable, and natural seedlings may appear in countless quantities at the beginning of the rainy season, only to disappear largely or entirely within a comparatively short

  14. Rice seedling and plant development as affected by increasing rates of penoxsulam under controlled environments Desenvolvimento de plântulas e plantas adultas de arroz em função de doses crescentes de penoxsulam em ambiente controlado

    Directory of Open Access Journals (Sweden)

    G. Concenço

    2006-01-01

    Full Text Available Rice is a major staple in many countries. Weed control is one of the factors limiting higher rice yield. ALS (acetolactate synthase-inhibiting herbicides are desirable weed control herbicides because of their high efficacy, low toxicity to mammalians, and low rates used. An important herbicide characteristic is high selectivity to the crop, since it facilitates fast crop establishment and greater crop advantage over the weeds. The objectives of this work were to study the effects of increasing rates of the ALS-inhibiting herbicide penoxsulam on seed integrity and germination, and seedling and plant development of rice cv. BRS Pelota under controlled laboratory and greenhouse conditions. The results showed that penoxsulam affected rice germination and seedling and plant growth at rates above 54 g a.i. ha-1, and that penoxsulam is safe for rice seedling development at the currently recommended rates.O arroz é componente importante da dieta humana em vários países. Entre os fatores que limitam o aumento na sua produtividade está o controle de plantas daninhas. Os herbicidas inibidores da ALS (acetolactato sintase são preferidos em razão da alta eficiência no controle de plantas daninhas, da baixa toxicidade aos mamíferos e das baixas doses utilizadas. Uma característica importante que um herbicida deve possuir é a alta seletividade à cultura, pois ela implica estabelecimento mais rápido, com vantagem competitiva sobre as plantas daninhas. O objetivo deste trabalho foi estudar os efeitos do herbicida inibidor da ALS penoxsulam em doses crescentes sobre a integridade e germinação das sementes, bem como sobre o desenvolvimento inicial das plântulas e da planta adulta do cultivar BRS Pelota, sob condições de ambiente controlado (laboratório e casa de vegetação. Os resultados mostraram que o penoxsulam afetou a germinação e o crescimento de plântulas e plantas adultas nas doses acima de 54 g i.a. ha-1 e que ele é seguro para o

  15. Stipa tenacissima Does not Affect the Foliar δ13C and δ15N of Introduced Shrub Seedlings in a Mediterranean Semi-arid Steppe

    Institute of Scientific and Technical Information of China (English)

    Fernando T. Maestre; Susana Bautista; Jordi Cortina

    2006-01-01

    Recent studies have shown that the tussock grass Stipa tenacissima L. facilitates the establishment of late-successional shrubs, in what constitutes the first documented case of facilitation of woody plants by grasses. With the aim of increasing our knowledge of this interaction, in the present study we investigated the effects of S. tenacissima on the foliar δ13C, δ15N, nitrogen concentration, and carbon: nitrogen ratio of introduced seedlings of Pistacia lentiscus L., Quercus coccifera L., and Medicago arborea L. in a semi-arid Mediterranean steppe. Six months after planting, the values of δ13C ranged between -26.9‰ and -29.6‰,whereas those of δ15N ranged between -1.9‰ and 2.7‰. The foliar C: N ratio ranged between 10.7 and 53.5,and the nitrogen concentration ranged between 1.0% and 4.4%. We found no significant effect of the microsite provided by S. tenacissima on these variables in any of the species evaluated. The values of δ13C were negatively correlated with predawn water potentials in M. arborea and were positively correlated with relative growth rate in Q. coccifera. The values of δ15N were positively correlated with the biomass allocation to roots in the latter species. The present results suggest that the modification of environmental conditions in the are surrounding S. tenacissima was not strong enough to modify the foliar isotopic and nitrogen concentration of shrubs during the early stages after planting.

  16. Scientific computing an introduction using Maple and Matlab

    CERN Document Server

    Gander, Walter; Kwok, Felix

    2014-01-01

    Scientific computing is the study of how to use computers effectively to solve problems that arise from the mathematical modeling of phenomena in science and engineering. It is based on mathematics, numerical and symbolic/algebraic computations and visualization. This book serves as an introduction to both the theory and practice of scientific computing, with each chapter presenting the basic algorithms that serve as the workhorses of many scientific codes; we explain both the theory behind these algorithms and how they must be implemented in order to work reliably in finite-precision arithmetic. The book includes many programs written in Matlab and MapleMaple is often used to derive numerical algorithms, whereas Matlab is used to implement them. The theory is developed in such a way that students can learn by themselves as they work through the text. Each chapter contains numerous examples and problems to help readers understand the material “hands-on”.

  17. Sap-Sugar Content of Grafted Sugar Maple Trees

    Science.gov (United States)

    Maurice E. Jr. Demeritt; Maurice E. Jr. Demeritt

    1985-01-01

    In March and April 1983, 289 and 196 young grafted sugar maple trees were tapped and evaluated for sap-sugar content. In April, sap was collected from taps both above and below the graft union. Diameter of all tapped trees at 18 inches above the ground was measured. Analysis of the data revealed that: (1) trees selected for high sugar yield cannot be reproduced by...

  18. Root starch in defoliated sugar maples following thrips damage

    Science.gov (United States)

    Barbara S. Burns

    1991-01-01

    Sugar maple root starch evaluations were done in 1987 and 1988 as a service to Vermont sugarmakers concerned about tree health. Trees were rated for starch content in late fall, using a visual iodine-staining technique. On the average, trees with heavy pear thrips damage in the spring of 1988 had higher levels of root starch the following fall than trees with light or...

  19. The role of bigleaf maple in soil chemistry and nutrient dynamics in coastal temperate forests

    OpenAIRE

    Turk, Tanya D.

    2006-01-01

    The influence of bigleaf maple (Acer macrophyllum Pursh) in a forest dominated by Douglas-fir [Pseudotsuga menziessi (Mirb.) Franco] and western hemlock [Tsuga heterophylla (RAF.) Sarg.] was studied in a paired-plot design through an examination of the annual contribution of bigleaf maple litterfall to nutrient flux, its rate of decay, and its properties within the forest floor and mineral soil. Compared to conifer plots, bigleaf maple plots had litterfall significantly higher in all elements...

  20. Water ice as a matrix for film production by matrix assisted pulsed laser evaporation (MAPLE)

    DEFF Research Database (Denmark)

    Rodrigo, Katarzyna Agnieszka; Schou, Jørgen; Christensen, Bo Toftmann

    2007-01-01

    We have studied water ice as a matrix for the production of PEG (polyethylene glycol) films by MAPLE at 355 nm. The deposition rate is small compared with other matrices typically used in MAPLE, but the deposition of photofragments from the matrix can be avoided. At temperatures above -50 degrees...... of the target holder the deposition rate increases strongly, but the evaporation pressure in the MAPLE chamber also increases drastically....

  1. Water ice as a matrix for film production by matrix assisted pulsed laser evaporation (MAPLE)

    DEFF Research Database (Denmark)

    Rodrigo, Katarzyna Agnieszka; Schou, Jørgen; Christensen, Bo Toftmann;

    2007-01-01

    We have studied water ice as a matrix for the production of PEG (polyethylene glycol) films by MAPLE at 355 nm. The deposition rate is small compared with other matrices typically used in MAPLE, but the deposition of photofragments from the matrix can be avoided. At temperatures above -50 degrees...... of the target holder the deposition rate increases strongly, but the evaporation pressure in the MAPLE chamber also increases drastically....

  2. Canada's maple syrup industry%加拿大枫糖业

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Maple syrup is a natural product with no coloring agents or additives. Canada produces about 85 per cent of the world's maple syrup. Marketing has evolved from selling to traditional markets to more value added markets such as blends with other products (cereals, yogurt, etc.). This industry contributes to Canada's value added exports, since more than 60 per cent of maple exports are now shipped in pre packaged containers.

  3. Inhibitory effect of maple syrup on the cell growth and invasion of human colorectal cancer cells.

    Science.gov (United States)

    Yamamoto, Tetsushi; Uemura, Kentaro; Moriyama, Kaho; Mitamura, Kuniko; Taga, Atsushi

    2015-04-01

    Maple syrup is a natural sweetener consumed by individuals of all ages throughout the world. Maple syrup contains not only carbohydrates such as sucrose but also various components such as organic acids, amino acids, vitamins and phenolic compounds. Recent studies have shown that these phenolic compounds in maple syrup may possess various activities such as decreasing the blood glucose level and an anticancer effect. In this study, we examined the effect of three types of maple syrup, classified by color, on the cell proliferation, migration and invasion of colorectal cancer (CRC) cells in order to investigate whether the maple syrup is suitable as a phytomedicine for cancer treatment. CRC cells that were administered maple syrup showed significantly lower growth rates than cells that were administered sucrose. In addition, administration of maple syrup to CRC cells caused inhibition of cell invasion, while there was no effect on cell migration. Administration of maple syrup clearly inhibited AKT phosphorylation, while there was no effect on ERK phosphorylation. These data suggest that maple syrup might inhibit cell proliferation and invasion through suppression of AKT activation and be suitable as a phytomedicine for CRC treatment, with fewer adverse effects than traditional chemotherapy.

  4. Comparative Analysis of Milled Wood Lignins (MWLs Isolated from Sugar Maple (SM and Hot-Water Extracted Sugar Maple (ESM

    Directory of Open Access Journals (Sweden)

    Mangesh J. Goundalkar

    2014-03-01

    Full Text Available To further elucidate the advantageous effects of hot-water extraction (HWE on delignification, milled wood lignin (MWL was isolated from sugar maple (SM and from hot-water extracted sugar maple (ESM. Ball-milled wood was analyzed for particle size distribution (PSD before and after dioxane:water (DW extraction. The MWL samples were analyzed by analytical and spectral methods. The results indicated that the MWL isolated from SM and ESM was mainly released from the middle lamella (ML and the secondary wall (SW, respectively. The cleavage of dibenzodioxocin (DB and spirodienone (SD lignin substructures during HWE is suggested. The removal of lignin during acetone:water (AW extraction of hot-water extracted wood indicates that including an additional operation in a hardwood HWE-based biorefinery would be beneficial for processing of wood.

  5. The Effects of Electron Beam Irradiation Dose on the Mechanical Performance of Red Maple (Acer rubrum

    Directory of Open Access Journals (Sweden)

    Timothy Starr

    2014-12-01

    Full Text Available To understand how electron beam irradiation affects wood physically and chemically, irradiated maple beams (Acer rubrum and veneers were examined using three-point bend tests, dynamic mechanical analysis (DMA, and NIR- and FTIR- spectroscopy. The MOR from the bending tests revealed a significant decline in the red maple’s strength after a dose of 80 kGy. DMA results showed evidence of crosslinking of the amorphous content of the wood at low doses, followed by degradation at higher doses, with the change in response occurring around 80 kGy. Infrared spectroscopy revealed that the components of wood that were most impacted were the phenolic hydroxyl structures of lignin and cellulose hydroxyls, with the greatest effects being seen after 80 kGy.

  6. The first use of N-carbamylglutamate in a patient with decompensated maple syrup urine disease.

    Science.gov (United States)

    Kalkan Ucar, Sema; Coker, Mahmut; Habif, Sara; Saz, Eylem Ulas; Karapinar, Bulent; Ucar, Hakan; Kitis, Omer; Duran, Marinus

    2009-09-01

    Maple syrup urine disease (MSUD) is a defect in the catabolism of the branched-chain amino acids; leucine, isoleucine, and valine. Affected patients may also develop hyperammonaemia of unknown etiology. This report describes a four-year-old girl with MSUD, who presented with decompensated hyperleucinaemia with hyperammonaemia. The oral administration of the N-acetylglutamate analogue, N-carbamylglutamate (NCG), 200 mg/kg/day as a loading dose, and 100 mg/kg/day as a maintenance dose, in combination with standard therapy resulted in a significant decrease of plasma ammonia levels. This observation suggests that NCG may be an important adjunct to standard therapy in the management of decompensated MSUD patients with high leucine and ammonia levels. Supportive evidence from either randomized controlled trials or a large prospective cohort study is needed to confirm this interesting finding.

  7. Effects of graphene on seed germination and seedling growth

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Ming; Gao, Bin, E-mail: bg55@ufl.edu [University of Florida, Department of Agricultural and Biological Engineering (United States); Chen, Jianjun [University of Florida, Department of Environmental Horticulture and Mid-Florida Research & Education Center (United States); Li, Yuncong [University of Florida, Soil and Water Science Department Tropical Research & Education Center (United States)

    2015-02-15

    The environmental impact of graphene has recently attracted great attention. In this work, we show that graphene at a low concentration affected tomato seed germination and seedling growth. Graphene-treated seeds germinated much faster than control seeds. Analytical results indicated that graphene penetrated seed husks. The penetration might break the husks to facilitate water uptake, resulting in faster germination and higher germination rates. At the stage of seedling growth, graphene was also able to penetrate root tip cells. Seedlings germinated from graphene-treated seeds had slightly lower biomass accumulation than the control, but exhibited significantly longer stems and roots than the control, which suggests that graphene, in contrast with other nanoparticles, had different effects on seedling growth. Taken together, our results imply that graphene played complicated roles in affecting the initial stage of seed germination and subsequent seedling growth.

  8. Passive Maple-Seed Robotic Fliers for Education, Research and Entrepreneurship

    Science.gov (United States)

    Aslam, D. M.; Abu-Ageel, A.; Alfatlawi, M.; Varney, M. W.; Thompson, C. M.; Aslam, S. K.

    2014-01-01

    As inspirations from flora and fauna have led to many advances in modern technology, the concept of drawing ideas from nature for design should be reflected in engineering education. This paper focuses on a maple-seed robotic flier (MRF) with various complexities, a robotic platform modeled after the samaras of maple or ash trees, to teach STEM…

  9. Sugar maple: abundance and site relationships in the pre- and post- settlement forest

    Science.gov (United States)

    Gordon G. Whitney

    1999-01-01

    A review of the available historical evidence provides a picture of sugar maple's site relationstiips in the presettlement forest and its changing statis over the last 300 years. Sugar maple was widely distributed throughout the Northeast during the presettlerment period. it was particularly abundant on the richer, better drained, silt-rich sites. A comparison of...

  10. Phenology and recruitment of Ohio buckeye and sugar maple in Illinois forest stands

    Science.gov (United States)

    Michelle Henderson; Jeffery O. Dawson; Evan H. DeLucia

    1993-01-01

    Phenological patterns, light conditions, and photosynthetic activity of Ohio buckeye and sugar maple foliage on trees in the forest understory were monitored and compared over two growing seasons in two mesophytic upland woodlands in central Illinois. Ohio buckeye began leaf expansion three to four weeks earlier than sugar maple, started leaf senescence and shedding in...

  11. Processing of C60 thin films by Matrix-Assisted Pulsed Laser Evaporation (MAPLE)

    DEFF Research Database (Denmark)

    Canulescu, Stela; Schou, Jørgen; Fæster, Søren

    2011-01-01

    Thin films of fullerenes (C60) were deposited onto silicon using matrix-assisted pulsed laser evaporation (MAPLE). The deposition was carried out from a frozen homogeneous dilute solution of C60 in anisole (0.67 wt%), and over a broad range of laser fluences, from 0.15 J/cm2 up to 3.9 J/cm2. MAPLE...

  12. A study on matrix assisted pulsed evaporation (MAPLE) of organic materials

    DEFF Research Database (Denmark)

    Matei, Andreea; Canulescu, Stela; Constantinescu, Catalin

    2012-01-01

    Organic films can be produced either by MAPLE or directly by PLD (Pulsed laser deposition). For a reasonable deposition rate of ng/cm2 per pulse for film production by MAPLE a fluence of 1-1.5 J/cm2 is required at the laser wavelength of 355 nm, while the fluence can be considerably lower at 248 ...

  13. Use of damage surveys and field inventories to evaluate oak and sugar maple health in the northern United States

    Science.gov (United States)

    Randall S Morin; Christopher W. Woodall; Jim Steinman; Charles H. Perry

    2009-01-01

    Oak species (Quercus spp.) and sugar maple (Acer saccharum) are substantial components of the forest ecosystems in the 24-state region spanning the northern U.S. During recent decades, both damage surveys and forest inventories have documented declines of sugar maple and oak health. In order to more fully assess the status of oak and sugar maple health, we examined...

  14. Differential effects of sugar maple, red oak, and hemlock tannins on carbon and nitrogen cycling in temperate forest soils.

    Science.gov (United States)

    Talbot, Jennifer M; Finzi, Adrien C

    2008-03-01

    Tannins are abundant secondary chemicals in leaf litter that are hypothesized to slow the rate of soil-N cycling by binding protein into recalcitrant polyphenol-protein complexes (PPCs). We studied the effects of tannins purified from sugar maple, red oak, and eastern hemlock leaf litter on microbial activity and N cycling in soils from northern hardwood-conifer forests of the northeastern US. To create ecologically relevant conditions, we applied tannins to soil at a concentration (up to 2 mg g(-1) soil) typical of mineral soil horizons. Sugar maple tannins increased microbial respiration significantly more than red oak or hemlock tannins. The addition of sugar maple tannins also decreased gross N mineralization by 130% and, depending upon the rate of application, decreased net rates of N mineralization by 50-290%. At low concentrations, the decrease in mineralization appeared to be driven by greater microbial-N immobilization, while at higher concentrations the decrease in mineralization was consistent with the formation of recalcitrant PPCs. Low concentrations of red oak and hemlock tannins stimulated microbial respiration only slightly, and did not significantly affect fluxes of inorganic N in the soil. When applied to soils containing elevated levels of protein, red oak and hemlock tannins decreased N mineralization without affecting rates of microbial respiration, suggesting that PPC formation decreased substrate availability for microbial immobilization. Our results indicate that tannins from all three species form recalcitrant PPCs, but that the degree of PPC formation and its attendant effect on soil-N cycling depends on tannin concentration and the pool size of available protein in the soil.

  15. Estabelecimento de plântulas e desempenho de plantas em resposta ao vigor dos aquênios de girassol Seedlings establishment and plants performance as affected by sunflower achenes vigour

    Directory of Open Access Journals (Sweden)

    Madelon Rodrigues Sá Braz

    2009-10-01

    sunflower achenes, cultivar 'Embrapa 122 V2000', with distinct vigorous levels. Plant population was evaluated at 10, 20, 40, 60, 80 and 100 days after sowing (DAS. Plant height, leaf number, stem diameter and dry matter production were evaluated at 20, 40, 60, 80 and 100DAS. At harvest (100DAS the number of achenes per plant, mass of 1000 achenes and achenes yield (g plant-1 and kg ha-1 were also evaluated. Two and six months after harvest, the achenes were submitted to the following tests: germination, first count, accelerated aging, seedling emergence in sand, length of seedlings and electrical conductivity. The results indicated that achenes vigour affected plant population at 60DAS. Vigorous sunflower achenes improved the development of plants beyond 60DAS and this effect may persist until the final production, at initial population absence.

  16. Solving Nonlinear Partial Differential Equations with Maple and Mathematica

    CERN Document Server

    Shingareva, Inna K

    2011-01-01

    The emphasis of the book is given in how to construct different types of solutions (exact, approximate analytical, numerical, graphical) of numerous nonlinear PDEs correctly, easily, and quickly. The reader can learn a wide variety of techniques and solve numerous nonlinear PDEs included and many other differential equations, simplifying and transforming the equations and solutions, arbitrary functions and parameters, presented in the book). Numerous comparisons and relationships between various types of solutions, different methods and approaches are provided, the results obtained in Maple an

  17. Chronic drought stress reduced but not protected Shantung maple (Acer truncatum Bunge) from adverse effects of ozone (O3) on growth and physiology in the suburb of Beijing, China.

    Science.gov (United States)

    Li, Li; Manning, William J; Tong, Lei; Wang, Xiaoke

    2015-06-01

    A two-year experiment exposing Acer truncatum Bunge seedlings to elevated ozone (O3) concentrations above ambient air (AO) and drought stress (DS) was carried out using open-top chambers (OTCs) in a suburb of Beijing in north China in 2012-2013. The results suggested that AO and DS had both significantly reduced leaf mass area (LMA), stomatal conductance (Gs), light saturated photosynthetic rate (Asat) as well as above and below ground biomass at the end of the experiment. It appeared that while drought stress mitigated the expression of foliar injury, LMA, leaf photosynthetic pigments, height growth and basal diameter, due to limited carbon fixation, the O3 - induced reductions in Asat, Gs and total biomass were enhanced 23.7%. 15.5% and 8.1% respectively. These data suggest that when the whole plant was considered that drought under the conditions of this experiment did not protect the Shantung maple seedlings from the effects of O3.

  18. Responses of Tree Seedlings to a Changing Atmosphere: Effects of Carbon Dioxide, Nitrogen Dioxide, and Ozone

    Science.gov (United States)

    Eller, A. S.; Sparks, J. P.

    2008-12-01

    Human activities have caused changes in the chemical composition of the atmosphere: the concentrations of carbon dioxide (CO2), nitrogen dioxide (NO2), and ozone (O3) have increased and are expected to continue increasing in the future. These gases have the potential to alter plant physiological processes, change growth rates, C:N, and carbon storage potential. The responses of tree seedlings to these changes will have a profound impact on the species composition and carbon storage potential of forests in the future. Others have found CO2 tends to increase plant growth and O3 to decrease it. NO2, if assimilated by plants, can be a source of nutrient nitrogen, but is also an oxidant with the potential to damage cell membranes and decrease growth. The objectives of this study were to determine the single and combined effects of CO2, NO2, and O3 on sugar maple, eastern hemlock, and two clones of trembling aspen. The trees were fumigated for two growing seasons with elevated (40ppb) or ambient NO2, elevated (560ppm) or ambient CO2, elevated (100 ppb 5 days/week) or ambient O3, and with or without additional soil nitrate (30 kg ha-1 yr-1) to simulate ecosystems with and without nitrogen limitation. We found that elevated CO2 increased total biomass of both maples and hemlocks. Further, the CO2 growth effect was most striking when combined with elevated O2; elevated CO2 eliminated the growth decrease induced by O3 especially when nitrogen was limited. Elevated NO2 had no effect on maple seedlings, but, similar to CO2, eliminated the decrease in growth under O3 on hemlock seedlings. The two aspen clones differed in their resistance to ozone. The non-resistant clone exhibited growth responses similar to maple. However, the resistant clone did not exhibit a growth response under any gas treatment regardless of soil nitrogen status. The variation in responses among species, within clones of the same species, and between fumigations was large in this study and suggests

  19. Dynamics of a freely-falling maple seed

    Science.gov (United States)

    Lee, Injae; Choi, Haecheon

    2016-11-01

    We conduct numerical simulations of a freely-falling maple seed using an immersed boundary method in a non-inertial reference frame. A three-dimensional seed model is obtained by scanning a maple seed. The seed reaches a steady autorotation after a transient period, and a stable leading-edge vortex is attached on the surface of the rotating seed, which increases the drag force during autorotation. In addition, two different approaches are considered to obtain scaling laws describing the relation among the seed weight and geometry, and descending and rotating velocities. The first uses the conservations of mass, linear and angular momentum, and energy. In this approach, a model constant to be determined, called axial induction factor, is obtained from the result of present simulation. The second approach employs a classical steady wing theory in which the vortical strength is scaled with the circulation around a wing and the lift force is modeled by the time derivative of vortical impulse. Available data on various seeds well fall on these scaling laws. Supported by NRF-2014M3C1B1033848.

  20. Organic heterostructures deposited by MAPLE on AZO substrate

    Science.gov (United States)

    Socol, M.; Preda, N.; Stanculescu, A.; Breazu, C.; Florica, C.; Stanculescu, F.; Iftimie, S.; Girtan, M.; Popescu-Pelin, G.; Socol, G.

    2017-09-01

    Organic heterostructures based on poly(3-hexylthiophene) (P3HT) and fullerene (C60) as blends or multilayer were deposited on Al:ZnO (AZO) by Matrix-Assisted Pulsed Laser Evaporation (MAPLE) technique. The AZO layers were obtained by Pulsed Laser Deposition (PLD) on glass substrate, the high quality of the films being reflected by the calculated figure of merit. The organic heterostructures were investigated from morphological, optical and electrical point of view by atomic force microscopy (AFM), UV-vis spectroscopy, photoluminescence (PL) and current-voltage (I-V) measurements, respectively. The increase of the C60 content in the blend heterostructure has as result a high roughness. Compared with the multilayer heterostructure, those based on blends present an improvement in the electrical properties. Under illumination, the highest current value was recorded for the heterostructure based on the blend with the higher C60 amount. The obtained results showed that MAPLE is a useful technique for the deposition of the organic heterostructures on AZO as transparent conductor electrode.

  1. Laccase from Sycamore Maple (Acer pseudoplatanus) Polymerizes Monolignols.

    Science.gov (United States)

    Sterjiades, R; Dean, J F; Eriksson, K E

    1992-07-01

    Current understanding of the final oxidative steps leading to lignin deposition in trees and other higher plants is limited with respect to what enzymes are involved, where they are localized, how they are transported, and what factors regulate them. With the use of cell suspension cultures of sycamore maple (Acer pseudoplatanus), an in-depth study of laccase, one of the oxidative enzymes possibly responsible for catalyzing the dehydrogenative polymerization of monolignols in the extracellular matrix, was undertaken. The time course for secretion of laccase into suspension culture medium was determined with respect to age and mass of the cells. Laccase was completely separated from peroxidase activity by hydrophobic interaction column chromatography, and its purity was assessed with different types of gel electrophoresis (isoelectric focusing-, native-, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis). Amino acid and glycosyl analyses of the purified enzyme were compared with those reported from previous studies of plant and fungal laccases. The specific activity of laccase toward several common substrates, including monolignols, was determined. Unlike a laccase purified from the Japanese lacquer tree (Rhus vernicifera), laccase from sycamore maple oxidized sinapyl, coniferyl, and p-coumaryl alcohols to form water-insoluble polymers (dehydrogenation polymers).

  2. An Experimental Study on the aerodynamic and aeroacoustic performances of Maple-Seed-Inspired UAV Propellers

    Science.gov (United States)

    Hu, Hui; Ning, Zhe

    2016-11-01

    Due to the auto-rotating trait of maple seeds during falling down process, flow characteristics of rotating maple seeds have been studied by many researchers in recent years. In the present study, an experimental investigation was performed to explore maple-seed-inspired UAV propellers for improved aerodynamic and aeroacoustic performances. Inspired by the auto-rotating trait of maple seeds, the shape of a maple seed is leveraged for the planform design of UAV propellers. The aerodynamic and aeroacoustic performances of the maple-seed-inspired propellers are examined in great details, in comparison with a commercially available UAV propeller purchased on the market (i.e., a baseline propeller). During the experiments, in addition to measuring the aerodynamic forces generated by the maple-seed-inspired propellers and the baseline propeller, a high-resolution Particle Image Velocimetry (PIV) system was used to quantify the unsteady flow structures in the wakes of the propellers. The aeroacoustic characteristics of the propellers are also evaluated by leveraging an anechoic chamber available at the Aerospace Engineering Department of Iowa State University. The research work is supported by National Science Foundation under Award Numbers of OSIE-1064235.

  3. How fresh is maple syrup? Sugar maple trees mobilize carbon stored several years previously during early springtime sap-ascent.

    Science.gov (United States)

    Muhr, Jan; Messier, Christian; Delagrange, Sylvain; Trumbore, Susan; Xu, Xiaomei; Hartmann, Henrik

    2016-03-01

    While trees store substantial amounts of nonstructural carbon (NSC) for later use, storage regulation and mobilization of stored NSC in long-lived organisms like trees are still not well understood. At two different sites with sugar maple (Acer saccharum), we investigated ascending sap (sugar concentration, δ(13) C, Δ(14) C) as the mobilized component of stored stem NSC during early springtime. Using the bomb-spike radiocarbon approach we were able to estimate the average time elapsed since the mobilized carbon (C) was originally fixed from the atmosphere and to infer the turnover time of stem storage. Sites differed in concentration dynamics and overall δ(13) C, indicating different growing conditions. The absence of temporal trends for δ(13) C and Δ(14) C indicated sugar mobilization from a well-mixed pool with average Δ(14) C consistent with a mean turnover time (TT) of three to five years for this pool, with only minor differences between the sites. Sugar maple trees hence appear well buffered against single or even several years of negative plant C balance from environmental stress such as drought or repeated defoliation by insects. Manipulative investigations (e.g. starvation via girdling) combined with Δ(14) C measurements of this mobilized storage pool will provide further new insights into tree storage regulation and functioning.

  4. Economic Phenomena Via Mathematical Modelling in Maple System Ekonominių reiškinių matematinis modeliavimas Maple sistema

    Directory of Open Access Journals (Sweden)

    Zuzana Chvatalova

    2011-11-01

    Full Text Available Nowadays, economics utilizes more and more frequently quantitative methods. This is an important phenomenon in the process of education. The paper deals with application of the Maple system for on-line creation of mathematical models in economic sectors. Means of Maple represent an important challenge for application in practice or research – resolve specific problems, apply mathematical models in many science fields, create intelligent documents for the presentation of modelling and analyses with computations, visualizations, animations, simulations. The paper incorporates selected samples of models in Maple and indicates further fields of its practical using, e.g. for measurement of marketing activity effectiveness.

    Šiuolaikinė ekonomika vis dažniau ir plačiau taiko kiekybinius metodus. Tai yra svarbus veiksnys ug­dymo procese. Straipsnyje nagrinėjamas Maple sistemos taikymas, matematinių modelių sukūrimas ir taikymas skirtinguose ekonominiuose sektoriuose. Jame apžvelgiamos plačios Maple sistemos taikymo praktikoje ir moksliniuose tyrimuose galimybės, sprendžiant konkrečias ekonomines problemas; ma­tematinių modelių taikymo

  5. Diffusion-weighted MRI of maple syrup urine disease encephalopathy

    Energy Technology Data Exchange (ETDEWEB)

    Cavalleri, F.; Mavilla, L. [Servizio di Neuroradiologia, Azienda Ospedaliera Policlinico, Modena (Italy); Berardi, A.; Ferrari, F. [Servizio di Neonatologia, Azienda Ospedaliera Policlinico, Modena (Italy); Burlina, A.B. [Dipartimento di Pediatria, Azienda Ospedaliera, Universita di Padova, Padua (Italy)

    2002-06-01

    We report the case of a newborn child with maple syrup urine disease (MSUD), diagnosed at 10 days of life. Diffusion-weighted echoplanar MRI showed marked hyperintensity of the cerebellar white matter, the brainstem, the cerebral peduncles, the thalami, the dorsal limb of the internal capsule and the centrum semiovale, while conventional dual-echo sequence evidenced only a weak diffuse T2 hyperintensity in the cerebellar white matter and in the dorsal brainstem. The apparent diffusion coefficient (ADC) of these regions was markedly (>80%) decreased. Therefore, in agreement with current hypotheses on MSUD pathogenesis, MSUD oedema proves to be a cytotoxic oedema. Diffusion-weighted MRI may be a valuable tool, more sensitive than conventional spin-echo techniques, to assess the extent and progression of cytotoxicity in MSUD, as well as the effectiveness of the therapeutic interventions. (orig.)

  6. Effects of invasive rats and burrowing seabirds on seeds and seedlings on New Zealand islands.

    Science.gov (United States)

    Grant-Hoffman, Madeline N; Mulder, Christa P H; Bellingham, Peter J

    2010-04-01

    Rats (Rattus rattus, Rattus norvegicus, Rattus exulans) are important invaders on islands. They alter vegetation indirectly by preying on burrowing seabirds. These seabirds affect vegetation through nutrient inputs from sea to land and physical disturbance through trampling and burrowing. Rats also directly affect vegetation though consumption of seeds and seedlings. Seedling communities on northern New Zealand islands differ in composition and densities among islands which have never been invaded by rats, are currently invaded by rats, or from which rats have been eradicated. We conducted experimental investigations to determine the mechanisms driving these patterns. When the physical disturbance of seabirds was removed, in soils collected from islands and inside exclosures, seedling densities increased with seabird burrow density. For example, seedling densities inside exclosures were 10 times greater than those outside. Thus the negative effects of seabirds on seedlings, by trampling and uprooting, overwhelm the potentially beneficial effects of high levels of seed germination, seedling emergence, and possibly seed production, which result from seed burial and nutrient additions. Potential seedling density was reduced on an island where rats were present, germination of seeds from soils of this island was approximately half that found on other islands, but on this island seedling density inside exclosures was 7 times the density outside. Although the total negative effects of seabirds and rats on seedling densities are similar (reduced seedling density), the differences in mechanisms and life stages affected result in very different filters on the plant community.

  7. Correlation of maple sap composition with bacterial and fungal communities determined by multiplex automated ribosomal intergenic spacer analysis (MARISA).

    Science.gov (United States)

    Filteau, Marie; Lagacé, Luc; LaPointe, Gisèle; Roy, Denis

    2011-08-01

    During collection, maple sap is contaminated by bacteria and fungi that subsequently colonize the tubing system. The bacterial microbiota has been more characterized than the fungal microbiota, but the impact of both components on maple sap quality remains unclear. This study focused on identifying bacterial and fungal members of maple sap and correlating microbiota composition with maple sap properties. A multiplex automated ribosomal intergenic spacer analysis (MARISA) method was developed to presumptively identify bacterial and fungal members of maple sap samples collected from 19 production sites during the tapping period. Results indicate that the fungal community of maple sap is mainly composed of yeast related to Mrakia sp., Mrakiella sp., Guehomyces pullulans, Cryptococcus victoriae and Williopsis saturnus. Mrakia, Mrakiella and Guehomyces peaks were identified in samples of all production sites and can be considered dominant and stable members of the fungal microbiota of maple sap. A multivariate analysis based on MARISA profiles and maple sap chemical composition data showed correlations between Candida sake, Janthinobacterium lividum, Williopsis sp., Leuconostoc mesenteroides, Mrakia sp., Rhodococcus sp., Pseudomonas tolaasii, G. pullulans and maple sap composition at different flow periods. This study provides new insights on the relationship between microbial community and maple sap quality.

  8. Paraformaldehyde pellet not necessary in vacuum-pumped maple sap system

    Science.gov (United States)

    H. Clay Smith; Carter B. Gibbs

    1970-01-01

    In a study of sugar maple sap collection through a vacuum-pumped plastic tubing system, yields were compared between tapholes in which paraformaldehyde pellets were used and tapholes without pellets, Use of the pellets did not increase yield.

  9. Impact of climate change, seedling type and provenance on the risk of damage to Norway spruce (Picea abies (L.) Karst.) seedlings in Sweden due to early summer frosts

    Energy Technology Data Exchange (ETDEWEB)

    Langvall, Ola (Swedish Univ. of Agricultural Sciences, Unit for Field-based Forest Research, Asa Forest Research Station, Lammhult (Sweden))

    2011-04-15

    A model including site-specific microclimate-affecting properties of a forest regeneration area together with seedling characteristics was used to evaluate the accumulated risk of frost damage to Norway spruce (Picea abies (L.) Karst.) seedlings. Climate change in Sweden was simulated on the basis of the regional climate model RCA3. The daily average temperature, the driving factor for bud burst in the model, was adjusted using the difference between the mean of the climate model data for the years 1961-1990 and 2036-2065. The model was run for a highly frost prone, clear-cut site in which bare-rooted Norway spruce seedlings of mid-Swedish provenance were planted. Alternate runs were conducted with data for containerized seedlings and seedlings of Belarusian origin. The study showed that bud burst will occur at earlier dates throughout Sweden in the period 2036-2065 if the climate changes according to either of the climate scenarios examined, compared to the reference period 1961-1990. Furthermore, the risk of damage to Norway spruce seedlings as a result of frost events during summer will increase in southern Sweden and be unaffected or decrease in northern Sweden. The risk of frost damage was exacerbated in containerized seedlings, while the risk was lower for the seedlings of Belarusian provenance when compared with bare-rooted seedlings or seedlings of mid-Swedish origin

  10. Movement Disorders in Adult Surviving Patients with Maple Syrup Urine Disease

    OpenAIRE

    Carecchio, M.; Schneider, S. A.; Chan, H; Lachmann, R.; Lee, P. J.; Murphy, E.; Bhatia, K P

    2011-01-01

    Maple syrup urine disease is a rare metabolic disorder caused by mutations in the branched-chain alpha-keto acid dehydrogenase complex gene. Patients generally present early in life with a toxic encephalopathy because of the accumulation of the branched-chain amino acids leucine, isoleucine, and valine and the corresponding ketoacids. Movement disorders in maple syrup urine disease have typically been described during decompensation episodes or at presentation in the context of a toxic enceph...

  11. Movement Disorders in Adult Surviving Patients with Maple Syrup Urine Disease

    OpenAIRE

    Carecchio, Miryam; Susanne A. Schneider; Chan, Heidi; Lachmann, Robin; Lee, Philip J; Murphy, Elaine; Bhatia, Kailash P

    2011-01-01

    Maple syrup urine disease is a rare metabolic disorder caused by mutations in the branched-chain α-keto acid dehydrogenase complex gene. Patients generally present early in life with a toxic encephalopathy because of the accumulation of the branched-chain amino acids leucine, isoleucine, and valine and the corresponding ketoacids. Movement disorders in maple syrup urine disease have typically been described during decompensation episodes or at presentation in the context of a toxic encephalop...

  12. Neighborhood and community interactions determine the spatial pattern of tropical tree seedling survival.

    Science.gov (United States)

    Queenborough, Simon A; Burslem, David F R P; Garwood, Nancy C; Valencia, Renato

    2007-09-01

    Factors affecting survival and recruitment of 3531 individually mapped seedlings of Myristicaceae were examined over three years in a highly diverse neotropical rain forest, at spatial scales of 1-9 m and 25 ha. We found convincing evidence of a community compensatory trend (CCT) in seedling survival (i.e., more abundant species had higher seedling mortality at the 25-ha scale), which suggests that density-dependent mortality may contribute to the spatial dynamics of seedling recruitment. Unlike previous studies, we demonstrate that the CCT was not caused by differences in microhabitat preferences or life history strategy among the study species. In local neighborhood analyses, the spatial autocorrelation of seedling survival was important at small spatial scales (1-5 m) but decayed rapidly with increasing distance. Relative seedling height had the greatest effect on seedling survival. Conspecific seedling density had a more negative effect on survival than heterospecific seedling density and was stronger and extended farther in rare species than in common species. Taken together, the CCT and neighborhood analyses suggest that seedling mortality is coupled more strongly to the landscape-scale abundance of conspecific large trees in common species and the local density of conspecific seedlings in rare species. We conclude that negative density dependence could promote species coexistence in this rain forest community but that the scale dependence of interactions differs between rare and common species.

  13. Arborescent palm seed morphology and seedling distribution

    OpenAIRE

    Rodolfo Salm

    2005-01-01

    This study examines how the seed morphology of two large arborescent palms, Attalea maripa (Aubl.) Mart. and Astrocaryum aculeatum G. Mey, may affect their seed shadow in a seasonally dry Amazonian forest. In addition to being smaller and produced in larger numbers than those of A. aculeatum, A. maripa seeds also presented a substantially lower amount of nutritional reserves available for the embryo. However, A. maripa seedlings were found in much higher numbers than those of A. aculeatum. Th...

  14. Invasive rats alter woody seedling composition on seabird-dominated islands in New Zealand.

    Science.gov (United States)

    Grant-Hoffman, Madeline N; Mulder, Christa P; Bellingham, Peter J

    2010-06-01

    Invasive rats (Rattus rattus, R. norvegicus, R. exulans) have large impacts on island habitats through both direct and indirect effects on plants. Rats affect vegetation by extirpating burrowing seabirds through consumption of eggs, chicks, and adults. These seabirds serve as ecosystem engineers, affecting plant communities by burying and trampling seeds and seedlings, and by altering microclimate. Rats also directly affect plant communities by consuming seeds and seedlings. We studied the direct and indirect impacts of rats on the seedlings of woody plants on 21 islands in northern New Zealand. We compared seedling densities and richness on islands which differed in status with respect to rats: nine islands where rats never invaded, seven islands where rats were present at the time of our study, and five islands where rats were either eradicated or where populations were likely to be small as a result of repeated eradications and re-invasions. In addition, we compared plots from a subset of the 21 islands with different burrow densities to examine the effects of burrowing seabirds on plants while controlling for other factors that differ between islands. We categorized plant communities by species composition and seedling density in a cluster analysis. We found that burrow densities explained more variation in seedling communities than rat status. In areas with high seabird burrow density seedling densities were low, especially for the smallest seedlings. Species richness and diversity of seedlings, but not seedling density, were most influenced by changes in microclimate induced by seabirds. Islands where rats had been eradicated or that had low rat populations had the lowest diversity and richness of seedlings (and adults), but the highest seedling density. Seedling communities on these islands were dominated by Pseudopanax lessonii and Coprosma macrocarpa. This indicates lasting effects of rats that may prevent islands from returning to pre-invasion states.

  15. Automated Probabilistic System Architecture Analysis in the Multi-Attribute Prediction Language (MAPL: Iteratively Developed using Multiple Case Studies

    Directory of Open Access Journals (Sweden)

    Robert Lagerström

    2017-07-01

    Full Text Available The Multi-Attribute Prediction Language (MAPL, an analysis metamodel for non-functional qualities of system architectures, is introduced. MAPL features automate analysis in five non-functional areas: service cost, service availability, data accuracy, application coupling, and application size. In addition, MAPL explicitly includes utility modeling to make trade-offs between the qualities. The article introduces how each of the five non-functional qualities are modeled and quantitatively analyzed based on the ArchiMate standard for enterprise architecture modeling and the previously published Predictive, Probabilistic Architecture Modeling Framework, building on the well-known UML and OCL formalisms. The main contribution of MAPL lies in the probabilistic use of multi-attribute utility theory for the trade-off analysis of the non-functional properties. Additionally, MAPL proposes novel model-based analyses of several non-functional attributes. We also report how MAPL has iteratively been developed using multiple case studies.

  16. Influence of bigleaf maple (Acer Macrophyllum Pursh) on soil properties in a conifer forest of southwest British Columbia

    OpenAIRE

    Chandler, Julia

    2006-01-01

    The overall objective of this research was to detect the influence of bigleaf maple (Acer macrophyllum Pursh) on soils in a conifer forest of southwest British Columbia. Forest floor properties were measured beneath bigleaf maple along six transects and on two 36 m x 36 m plots. Wavelet analysis, kriging, spatial autocorrelation analysis, local indicators of spatial association, and parametric statistics were used to explore and confirm bigleaf maple patterns of influence on surrounding soils...

  17. Strong microsite control of seedling recruitment in tundra

    DEFF Research Database (Denmark)

    Graae, Bente J; Ejrnæs, Rasmus; Lang, Simone I

    2011-01-01

    , the experimental seed addition showed that the microsite environment was even more important. For all species, seedling emergence peaked at the productive end of the gradient, irrespective of the adult niches realized. Disturbance promoted recruitment at all positions along the environmental gradient, not just......The inclusion of environmental variation in studies of recruitment is a prerequisite for realistic predictions of the responses of vegetation to a changing environment. We investigated how seedling recruitment is affected by seed availability and microsite quality along a steep environmental...... at high productivity. Early seedling emergence constituted the main temporal bottleneck in recruitment for all species. Surprisingly, winter mortality was highest at what appeared to be the most benign end of the gradient. The results highlight that seedling recruitment patterns are largely determined...

  18. [Effects of gap size on seedling natural regeneration in artificial Pinus tabulaeformis plantation].

    Science.gov (United States)

    Han, Wen-Juan; Yuan, Xiao-Qing; Zhang, Wen-Hui

    2012-11-01

    To clarify the effects of gap size created by thinning on the seedling natural regeneration in artificial Pinus tabulaeformis plantation, a plot investigation was conducted to study the ecological factors and the age structure, height, diameter, length of needles, and dry biomass of roots, stems, and needles of 1-10 year-old seedlings in different habitats, and a path analysis was made on the environmental factors affecting the seedling regeneration. Obvious differences were observed in the ecological factors in different size gaps and slope aspects. There lacked of above 3 year-old seedlings in understory and of above 7 year-old seedlings in small gap, and the seedlings of 5 and 6 year-old were lesser in big gap. The 1-10 year-old seedlings could be divided into 3 development phases, i. e. , 1-3 year-old, 4-7 year-old, and 8-10 year-old seedlings, among which, 1-3 year-old seedlings were critical for the establishment and growth of the population. The growth situation of the seedlings in different habitats was in order of big gap in shady slope > big gap in sunny slope > small gap in sunny slope > small gap in shady slope > understory in sunny slope > understory in shady slope. Path analysis showed light intensity had decisive positive effects on the seedling number of different development phases, shrub coverage had decisive negative effects on the seedling number of 4-7 year-old and 8-10 year-old phases, whereas humus dry mass had negative effects on the seedling number of 4-7 year-old but positive effects on the seedling number of 8-10 year-old. It was suggested that in the management of artificial P. tabulaeformis plantation, relatively high intensity thinning combined with shrub clearing should be adopted to provide favorable conditions for the sustainable development of P. tabulaeformis population.

  19. Ethanol production from hot-water sugar maple wood extract hydrolyzate: fermentation media optimization for Escherichia coli FBWHR

    National Research Council Canada - National Science Library

    Yang Wang; Chenhui Liang; Shijie Liu

    2015-01-01

    .... Response surface methodology was employed to investigate the effect of fermentation media on the ethanol production from concentrated hot-water sugar maple hemicellulosic wood extract hydrolyzate...

  20. Changes in plasma glucose in Otsuka Long-Evans Tokushima Fatty rats after oral administration of maple syrup.

    Science.gov (United States)

    Nagai, Noriaki; Yamamoto, Tetsushi; Tanabe, Wataru; Ito, Yoshimasa; Kurabuchi, Satoshi; Mitamura, Kuniko; Taga, Atsushi

    2015-01-01

    We investigate whether maple syrup is a suitable sweetener in the management of type 2 diabetes using the Otsuka Long-Evans Tokushima Fatty (OLETF) rat. The enhancement in plasma glucose (PG) and glucose absorption in the small intestine were lower after the oral administration of maple syrup than after sucrose administration in OLETF rats, and no significant differences were observed in insulin levels. These data suggested that maple syrup might inhibit the absorption of glucose from the small intestine and preventing the enhancement of PG in OLETF rats. Therefore, maple syrup might help in the prevention of type 2 diabetes.

  1. MR diffusion imaging and MR spectroscopy of maple syrup urine disease during acute metabolic decompensation

    Energy Technology Data Exchange (ETDEWEB)

    Jan, Wajanat; Wang, Zhiyue J. [Department of Radiology, University of Pennsylvania School of Medicine, Children' s Hospital of Philadelphia, Pennsylvania (United States); Zimmerman, Robert A. [Department of Radiology, University of Pennsylvania School of Medicine, Children' s Hospital of Philadelphia, Pennsylvania (United States); Department of Radiology, Children' s Hospital of Philadelphia, 34th Street and Civic Center Boulevard, PA 19104, Philadelphia (United States); Berry, Gerard T.; Kaplan, Paige B.; Kaye, Edward M. [Department of Pediatrics, University of Pennsylvania School of Medicine, The Children' s Hospital of Philadelphia, Philadelphia, Pennsylvania (United States)

    2003-06-01

    Maple syrup urine disease (MSUD) is an inborn error of amino acid metabolism, which affects the brain tissue resulting in impairment or death if untreated. Imaging studies have shown reversible brain edema during acute metabolic decompensation. The purpose of this paper is to describe the diffusion-weighted imaging (DWI) and spectroscopy findings during metabolic decompensation and to assess the value of these findings in the prediction of patient outcome. Six patients with the diagnosis of MSUD underwent conventional MR imaging with DWI during acute presentation with metabolic decompensation. Spectroscopy with long TE was performed in four of the six patients. Follow-up examinations were performed after clinical and metabolic recovery. DWI demonstrated marked restriction of proton diffusion compatible with cytotoxic or intramyelinic sheath edema in the brainstem, basal ganglia, thalami, cerebellar and periventricular white matter and the cerebral cortex. This was accompanied by the presence of an abnormal branched-chain amino acids (BCAA) and branched-chain alpha-keto acids (BCKA) peak at 0.9 ppm as well as elevated lactate on proton spectroscopy in all four patients. The changes in all six patients were reversed with treatment without evidence of volume loss or persistent tissue damage. The presence of cytotoxic or intramyelinic edema as evidenced by restricted water diffusion on DWI, with the presence of lactate on spectroscopy, could imply imminent cell death. However, in the context of metabolic decompensation in MSUD, it appears that changes in cell osmolarity and metabolism can reverse completely after metabolic correction. (orig.)

  2. A Classic Case of Maple Syrup Urine Disease and a Novel Mutation in the BCKDHA Gene

    Directory of Open Access Journals (Sweden)

    Alieh Mirzaee

    2017-09-01

    Full Text Available Background: Maple syrup urine disease (MSUD is an inherited branched-chain amino acid metabolic disorder caused by the deficiency in the branched-chain alpha-keto acid dehydrogenase (BCKD complex. In MSUD, elevation of the branched-chain amino acids, such as alpha-keto acid and alpha-hydroxy acid, occurs due to the BCKDC gene deficiency, appearing in the blood, urine, and cerebrospinal fluid, which leads to neurological damage and mental retardation. MSUD phenotypically penetrates due to the mutations in the coding genes of four subunits of the BCKD complex, including the BCKDHA, BCKDHB, DBT, and DLD genes.Case report: We aimed to report the cases of three families whose children were affected by MSUD and presented with symptomatic features during the first week of birth, which were identified by mass spectrometry. DNA study was performed as a diagnosis panel containing four encoded BCKDC subunit genes.Conclusion: In the current study, DNA analysis and phenotypic manifestations indicated a novel mutation of c.143delT, p.L48Rfs*15 in the BCKDHA gene in a homozygous state, which is a causative mutation for the classic MSUD phenotype. Early diagnosis and neonatal screening are recommended for the accurate and effective treatment of this disease

  3. Maple syrup urine disease (MSUD): screening for known mutations in Italian patients.

    Science.gov (United States)

    Parrella, T; Surrey, S; Iolascon, A; Sartore, M; Heidenreich, R; Diamond, G; Ponzone, A; Guardamagna, O; Burlina, A B; Cerone, R

    1994-01-01

    Maple syrup urine disease (MSUD) is an autosomal recessive disease due to deficiency of the branched-chain alpha-ketoacid dehydrogenase (BCKDH) caused by a large number of mutations. In the present study, DNA from Italian patients and their relatives was examined for three point mutations (Y393N in the E1 alpha gene, T841G and G1031A in the E2 gene) and two deletions (-G at the intron/exon border of exon 8 in the E2 gene and an 11 bp deletion in exon 1 of the E1 beta gene) using the polymerase chain reaction (PCR) followed by allele-specific oligonucleotide (ASO) hybridization, gene-scanning size analysis of fluorescent-tagged PCR products and/or automated DNA sequence analysis. Our results show that two different mutations account for 7 of the 20 mutant MSUD alleles. Two unrelated affected children, two of their parents and one sibling were carriers for the 11 bp deletion in the E1 beta gene, one patient and her mother were heterozygous for Y393N in E1 alpha, while T841G, G1031A and the -G deletion in E2 were not detected. This study is the first attempt to characterize at a nucleic acid level MSUD mutations in Italy. Our results indicate that additional defects are present in the Italian population and that, unlike the Mennonites, a number of different MSUD mutations exist in Italians.

  4. Effects of seed mass on seedling success in Artocarpus heterophyllus L., a tropical tree species of north-east India

    Science.gov (United States)

    Khan, M. L.

    2004-03-01

    I examined the effects of seed mass on performance of seedlings of Artocarpus heterophyllus L. (Moraceae), a large evergreen late successional shade-tolerant tree species in three contrasting light conditions. Seed mass varied many fold from 1.5 to 14 g in A. heterophyllus. Germination and germination time showed a significant correlation with seed mass. Germination differed significantly among three light regimes (50%, 25% and 3%). Seed mass and light level significantly affected seedling survival. The seedlings that emerged from large seeds survived better than those from small seeds under all light regimes. Survival of seedlings was maximum in 25% light regime for all seed mass classes but did not differ significantly from that at 50% light regime. Survival was significantly lower in 3% light as compared to 50% and 25% light regimes. Seedling vigor (expressed in terms of seedling height, leaf area and dry weight) was also significantly affected by seed mass and light regimes. Seedlings that emerged from larger seeds and grew under 50% light regime produced the heaviest seedlings, while those resulting from smaller seeds and grown under 3% light regime produced the lightest seedlings. Resprouting capacity of seedlings after clipping was significantly affected by seed mass and light regime. Seedlings emerging from larger seeds were capable of resprouting several times successively. Resprouting was more pronounced under 50% and 25% light regimes as compared to 3% light. Success of A. heterophyllus regeneration appears to be regulated by an interactive effect of seed mass and light regime.

  5. Maple Syrup Urine Disease Complicated with Kyphoscoliosis and Myelopathy

    Directory of Open Access Journals (Sweden)

    Jia-Woei Hou

    2016-10-01

    Full Text Available Maple syrup urine disease (MSUD is an autosomal recessive aminoacidopathy secondary to an enzyme defect in the catabolic pathway of the branched-chain amino acids (BCAAs: leucine, isoleucine, and valine. Accumulation of their corresponding keto-acids leads to encephalopathy if not treated in time. A newborn male patient was suspected to have MSUD after tandem mass study when he presented symptoms and signs suggestive neonatal sepsis, anemia, and diarrhea. Food restriction of BCAAs was started; however, acrodermatitis enteropathica-like skin eruptions occurred at age 2 months. The skin rashes resolved after adding BCAAs and adjusting the infant formula. At age 7 months, he suffered from recurrent skin lesions, zinc deficiency, osteoporosis, and kyphosis of the thoracic spine with acute angulation over the T11-T12 level associated with spinal compression and myelopathy. After supplementation of zinc products and pamidronate, skin lesions and osteopenia improved gradually. Direct sequencing of the DBT gene showed a compound heterozygous mutation [4.7 kb deletion and c.650-651insT (L217F or L217fsX223]. It is unusual that neurodegeneration still developed in this patient despite diet restriction. Additionally, brain and spinal magnetic resonance imaging, bone mineral density study, and monitoring of zinc status are suggested in MSUD patients.

  6. Effects of Seedbed Density on Seedling Morphological Characteristics of four Broadleaved Species

    Energy Technology Data Exchange (ETDEWEB)

    Yucedag, C.; Gailing, O.

    2012-11-01

    The aim of this study was to investigate the effects of seedling spacing on morphological characteristics of one year-old Amygdalus communis L., Prunus avium L., Pyrus elaeagnifolia Pall. and Eriolobus trilobatus (Poiret) Roemer seedlings under nursery conditions. Seedlings were grown in completely randomized blocks with four replications. Seedbeds were 1.2 m wide with 5 rows each 20 cm apart. Within-row spacings were chosen as 4, 8 and 12 cm to analyze the effect of seedlings density on growth performance. Seedling spacing significantly affected root collar diameter, shoot height, tap root length and number of fine roots in A. communis and P. avium, but not in P. elaeagnifolia and E. tribolatus. Additionally wider seedling spacings resulted in larger seedlings in A. communis and P. avium. In conclusion, it would be beneficial to use wider seedling spacing in order to obtain better seedling growth in A. communis and P. avium. Larger seedlings could also provide significant advantages because of reduced cultural activities and an expected higher growth and survival rate. (Author) 27 refs.

  7. Colonization with Arbuscular Mycorrhizal Fungi Promotes the Growth of Morus alba L. Seedlings under Greenhouse Conditions

    Directory of Open Access Journals (Sweden)

    Nan Lu

    2015-03-01

    Full Text Available Morus alba L. is an important tree species planted widely in China because of its economic value. In this report, we investigated the influence of two arbuscular mycorrhizal fungal (AMF species, Glomus mosseae and Glomus intraradices, alone and together, on the growth of M. alba L. seedlings under greenhouse conditions. The growth parameters and physiological performance of M. alba L. seedlings were evaluated 90 days after colonization with the fungi. The growth and physiological performance of M. alba L. seedlings were significantly affected by the AMF species. The mycorrhizal seedlings were taller, had longer roots, more leaves and a greater biomass than the non-mycorrhizae-treated seedlings. In addition, the AMF species-inoculated seedlings had increased root activity and a higher chlorophyll content compared to non-inoculated seedlings. Furthermore, AMF species colonization increased the phosphorus and nitrogen contents of the seedlings. In addition, simultaneous root colonization by the two AMF species did not improve the growth of M. alba L. seedlings compared with inoculation with either species alone. Based on these results, these AMF species may be applicable to mulberry seedling cultivation.

  8. Host plant phenology affects performance of an invasive weevil, Phyllobius oblongus (Coleoptera: Curculionidae), in a northern hardwood forest.

    Science.gov (United States)

    Coyle, David R; Jordan, Michelle S; Raffa, Kenneth F

    2010-10-01

    We investigated how host plant phenology and plant species affected longevity, reproduction, and feeding behavior of an invasive weevil. Phyllobius oblongus L. (Coleoptera: Curculionidae) is common in northern hardwood forests of the Great Lakes Region. Adults emerge in spring, feed on foliage of woody understory plants, and oviposit in the soil. Preliminary data indicate that adults often feed on sugar maple, Acer saccharum Marshall, foliage early in the season, then feed on other species such as raspberry, Rubus spp. Whether this behavior reflects temporal changes in the quality of A. saccharum tissue or merely subsequent availability of later-season plants is unknown. We tested adult P. oblongus in laboratory assays using young (newly flushed) sugar maple foliage, old (2-3 wk postflush) sugar maple foliage, and raspberry foliage. Raspberry has indeterminate growth, thus always has young foliage available for herbivores. Survival, oviposition, and leaf consumption were recorded. In performance assays under no-choice conditions, mated pairs were provided one type of host foliage for the duration of their lives. In behavioral choice tests, all three host plants were provided simultaneously and leaf area consumption was compared. Adults survived longer on and consumed greater amounts of young maple and raspberry foliage than old maple foliage. P. oblongus preferred young maple foliage to old maple foliage early in the season, however, later in the growing season weevils showed less pronounced feeding preferences. These results suggest how leaf phenology, plant species composition, and feeding plasticity in host utilization may interact to affect P. oblongus population dynamics.

  9. Biogeochemical Drivers of Sugar Maple Mortality at the Species-Range Scale

    Science.gov (United States)

    Perry, C. H.; Zimmerman, P. L.

    2012-12-01

    The decline of sugar maple in the northern United States is causing concern in the resource management community, and several studies have identified soil properties that are linked to the observation of dead/dying trees (Hallett et al. 2006; Horsley et al. 2000; Long et al. 2009; St.Clair et al. 2008). Unfortunately, the sample of trees supporting these studies tends to be purposive in nature; soil properties generally are assessed only on those plots where dead trees are observed. In this study, we used more than 200 plots from the USDA Forest Service's FIADB (USDA Forest Service 2012; Woudenberg et al. 2010), including the phase 3 soils data (O'Neill et al. 2005; Woodall et al. 2010), to analyze a broader population of sugar maple (alive and dead) across a wide range of soil types. This population of plots has a highly skewed, zero-inflated distribution: the number of plots in the sample without dead trees is an order of magnitude greater than the number of plots with dead trees. One effective method of analysis is a two-stage approach. In the first stage, the response variable is the presence or absence of dead sugar maple; the inferential space is the entire population of plots with sugar maple trees. The second stage uses the relative abundance of dead sugar maple as the response variable; in this case, inference is restricted to those plots where dead sugar maple trees are observed. In both sets of models, basal area and geology are significant predictors of dead sugar maple. The most significant soil variables vary between these two inferential spaces. Our model of the presence/absence of sugar maple death included the molar ratio of Mg:Mn; when conditional on the presence of dead sugar maple, our model includes the molar ratio of Ca:Al, along with exchangeable Na and Mg percentages. Multimodel inference (Burnham and Anderson 2002) assists the assessment of predictors within and between the two stages.

  10. Eucalyptus obliqua seedling growth in organic vs. mineral soil horizons.

    Science.gov (United States)

    Barry, Karen M; Janos, David P; Nichols, Scott; Bowman, David M J S

    2015-01-01

    Eucalyptus obliqua, the most widespread timber tree in Tasmania, is a pioneer after fire which can eliminate the organic layer of forest soil, exposing the underlying mineral soil. We compared seedling growth, mycorrhiza formation, and mineral nutrient limitation in organic layer vs. mineral soil. We grew E. obliqua seedlings separately in pots of organic layer and mineral soil in a glasshouse. Additional treatments of organic soil only, involved fully crossed methyl-bromide fumigation and fertilization. Fertilization comprised chelated iron for 121 days after transplant (DAT) followed by soluble phosphorus. At 357 DAT, whole plant dry weight was three times greater in ambient organic than in mineral soil. In organic soil, fumigation halved ectomycorrhiza abundance and reduced seedling growth at 149 DAT, but by 357 DAT when negative effects of fumigation on seedling growth had disappeared, neither fumigation nor fertilization affected mycorrhiza abundance. Iron fertilization diminished seedling growth, but subsequent phosphorus fertilization improved it. E. obliqua seedlings grow much better in organic layer soil than in mineral soil, although phosphorus remains limiting. The prevalent forestry practice of burning to mineral soil after timber harvest exposes a poor growth medium likely only partially compensated by fire-induced mineral soil alterations.

  11. Eucalyptus obliqua seedling growth in organic versus mineral soil horizons

    Directory of Open Access Journals (Sweden)

    Karen eBarry

    2015-02-01

    Full Text Available Eucalyptus obliqua, the most widespread timber tree in Tasmania, is a pioneer after fire which can eliminate the organic layer of forest soil, exposing the underlying mineral soil. We compared seedling growth, mycorrhiza formation, and mineral nutrient limitation in organic layer versus mineral soil. We grew E. obliqua seedlings separately in pots of organic layer and mineral soil in a glasshouse. Additional treatments of organic soil only, involved fully crossed methyl-bromide fumigation and fertilization. Fertilization comprised chelated iron for 121 days after transplant (DAT followed by soluble phosphorus. At 357 DAT, whole plant dry weight was three times greater in ambient organic than in mineral soil. In organic soil, fumigation halved ectomycorrhiza abundance and reduced seedling growth at 149 DAT, but by 357 DAT when negative effects of fumigation on seedling growth had disappeared, neither fumigation nor fertilization affected mycorrhiza abundance. Iron fertilization diminished seedling growth, but subsequent phosphorus fertilization improved it. E. obliqua seedlings grow much better in organic layer soil than in mineral soil, although phosphorus remains limiting. The prevalent forestry practice of burning to mineral soil after timber harvest exposes a poor growth medium likely only partially compensated by fire-induced mineral soil alterations.

  12. Calcium and aluminum impacts on sugar maple physiology in a northern hardwood forest.

    Science.gov (United States)

    Halman, Joshua M; Schaberg, Paul G; Hawley, Gary J; Pardo, Linda H; Fahey, Timothy J

    2013-11-01

    Forests of northeastern North America have been exposed to anthropogenic acidic inputs for decades, resulting in altered cation relations and disruptions to associated physiological processes in multiple tree species, including sugar maple (Acer saccharum Marsh.). In the current study, the impacts of calcium (Ca) and aluminum (Al) additions on mature sugar maple physiology were evaluated at the Hubbard Brook Experimental Forest (Thornton, NH, USA) to assess remediation (Ca addition) or exacerbation (Al addition) of current acidified conditions. Fine root cation concentrations and membrane integrity, carbon (C) allocation, foliar cation concentrations and antioxidant activity, foliar response to a spring freezing event and reproductive ability (flowering, seed quantity, filled seed and seed germination) were evaluated for dominant sugar maple trees in a replicated plot study. Root damage and foliar antioxidant activity were highest in Al-treated trees, while growth-associated C, foliar re-flush following a spring frost and reproductive ability were highest in Ca-treated trees. In general, we found that trees on Ca-treated plots preferentially used C resources for growth and reproductive processes, whereas Al-treated trees devoted C to defense-based processes. Similarities between Al-treated and control trees were observed for foliar cation concentrations, C partitioning and seed production, suggesting that sugar maples growing in native forests may be more stressed than previously perceived. Our experiment suggests that disruption of the balance of Ca and Al in sugar maples by acid deposition continues to be an important driver of tree health.

  13. RIR-MAPLE deposition of conjugated polymers and hybrid nanocomposites for application to optoelectronic devices

    Energy Technology Data Exchange (ETDEWEB)

    Stiff-Roberts, Adrienne D.; Pate, Ryan; McCormick, Ryan; Lantz, Kevin R. [Department of Electrical and Computer Engineering, Duke University Box 90291, Durham, NC 27708-0291, 919-660-5560 (United States)

    2012-07-30

    Resonant infrared matrix-assisted pulsed laser evaporation (RIR-MAPLE) is a variation of pulsed laser deposition that is useful for organic-based thin films because it reduces material degradation by selective absorption of infrared radiation in the host matrix. A unique emulsion-based RIR-MAPLE approach has been developed that reduces substrate exposure to solvents and provides controlled and repeatable organic thin film deposition. In order to establish emulsion-based RIR-MAPLE as a preferred deposition technique for conjugated polymer or hybrid nanocomposite optoelectronic devices, studies have been conducted to demonstrate the value added by the approach in comparison to traditional solution-based deposition techniques, and this work will be reviewed. The control of hybrid nanocomposite thin film deposition, and the photoconductivity in such materials deposited using emulsion-based RIR-MAPLE, will also be reviewed. The overall result of these studies is the demonstration of emulsion-based RIR-MAPLE as a viable option for the fabrication of conjugated polymer and hybrid nanocomposite optoelectronic devices that could yield improved device performance.

  14. Recovery of l-year-old loblolly pine seedlings from simulated browse damage

    Science.gov (United States)

    Michael G. Shelton; Michael D. Cain

    2002-01-01

    Loblolly pine (Pinus taeda L.) seedlings are frequently browsed by a wide variety of animals during the first few years of their development. Although anecdotal observations indicate that the potential for seedling recovery is good, there is little quantitative information on the factors affecting the recovery process. Thus, we conducted a study to...

  15. Variation among black walnut seedling families in resistance to competition and allelopathy

    Science.gov (United States)

    George Rink; J.W. Van Sambeek

    1985-01-01

    Of three environmental variables affecting black walnut seedling establishment, moisture stress overshadowed the effects of fescue leachate and fertilizer. Interactions between moisture stress and family and between fescue leachate and moisture stress for both seedling height and dry weight suggested that selection for tolerance to moisture stress is possible, whereas...

  16. AtRH57, a DEAD-box RNA helicase, is involved in feedback inhibition of glucose-mediated abscisic acid accumulation during seedling development and additively affects pre-ribosomal RNA processing with high glucose.

    Science.gov (United States)

    Hsu, Yi-Feng; Chen, Yun-Chu; Hsiao, Yu-Chun; Wang, Bing-Jyun; Lin, Shih-Yun; Cheng, Wan-Hsing; Jauh, Guang-Yuh; Harada, John J; Wang, Co-Shine

    2014-01-01

    The Arabidopsis thaliana T-DNA insertion mutant rh57-1 exhibited hypersensitivity to glucose (Glc) and abscisic acid (ABA). The other two rh57 mutants also showed Glc hypersensitivity similar to rh57-1, strongly suggesting that the Glc-hypersensitive feature of these mutants results from mutation of AtRH57. rh57-1 and rh57-3 displayed severely impaired seedling growth when grown in Glc concentrations higher than 3%. The gene, AtRH57 (At3g09720), was expressed in all Arabidopsis organs and its transcript was significantly induced by ABA, high Glc and salt. The new AtRH57 belongs to class II DEAD-box RNA helicase gene family. Transient expression of AtRH57-EGFP (enhanced green fluorescent protein) in onion cells indicated that AtRH57 was localized in the nucleus and nucleolus. Purified AtRH57-His protein was shown to unwind double-stranded RNA independent of ATP in vitro. The ABA biosynthesis inhibitor fluridone profoundly redeemed seedling growth arrest mediated by sugar. rh57-1 showed increased ABA levels when exposed to high Glc. Quantitative real time polymerase chain reaction analysis showed that AtRH57 acts in a signaling network downstream of HXK1. A feedback inhibition of ABA accumulation mediated by AtRH57 exists within the sugar-mediated ABA signaling. AtRH57 mutation and high Glc conditions additively caused a severe defect in small ribosomal subunit formation. The accumulation of abnormal pre-rRNA and resistance to protein synthesis-related antibiotics were observed in rh57 mutants and in the wild-type Col-0 under high Glc conditions. These results suggested that AtRH57 plays an important role in rRNA biogenesis in Arabidopsis and participates in response to sugar involving Glc- and ABA signaling during germination and seedling growth.

  17. Evaluation of Sugar Maple Dieback in the Upper Great Lakes Region and Development of a Forest Health Youth Education Program

    Science.gov (United States)

    Bal, Tara L.

    2013-01-01

    Sugar Maple, "Acer saccharum" Marsh., is one of the most valuable trees in the northern hardwood forests. Severe dieback was recently reported by area foresters in the western Upper Great Lakes Region. Sugar Maple has had a history of dieback over the last 100 years throughout its range and different variables have been identified as…

  18. Evaluation of Sugar Maple Dieback in the Upper Great Lakes Region and Development of a Forest Health Youth Education Program

    Science.gov (United States)

    Bal, Tara L.

    2013-01-01

    Sugar Maple, "Acer saccharum" Marsh., is one of the most valuable trees in the northern hardwood forests. Severe dieback was recently reported by area foresters in the western Upper Great Lakes Region. Sugar Maple has had a history of dieback over the last 100 years throughout its range and different variables have been identified as…

  19. Hypoglycin A Concentrations in Maple Tree Species in the Netherlands and the Occurrence of Atypical Myopathy in Horses

    NARCIS (Netherlands)

    Westermann, C.M.; Leeuwen, van R.; Raamsdonk, van L.W.D.; Mol, H.G.J.

    2016-01-01

    Background: Atypical myopathy (AM) in horses is caused by the plant toxin hypoglycin A, which in Europe typically is found in the sycamore maple tree (Acer pseudoplatanus). Owners are concerned about whether their horses are in danger if they graze near maple trees. Hypothesis/Objectives: To meas

  20. Medical isotope shortage 2009-2010 and future options NRU, SLOWPOKE and MAPLE

    Energy Technology Data Exchange (ETDEWEB)

    Hilborn, J. [Deep River, Ontario (Canada)

    2013-07-01

    The 15 month shutdown of NRU and the unexpected termination of the AECL/Nordion MAPLE project caused a world-wide shortage of medical isotopes. After the recent repair of NRU, AECL is confident that it could continue operating safely and reliably as a multi-purpose reactor until 2021 or longer. There is convincing evidence that the restoration of the MAPLE reactors is technically feasible, but it is highly improbable that a 10 MW MAPLE production reactor can ever be cost-effective. However, conversion of the present 10 MW reactors to 3 MW, without major changes to the structural hardware, warrants serious consideration. Finally, even the 20 kW SLOWPOKE reactor could produce useful quantities of Mo-99. If the present fuel rods were replaced with a small tank containing a solution of low-enriched uranyl sulphate in water, three of these liquid core reactors could supply all of Canada. (author)

  1. Characterization of MAPLE deposited WO3 thin films for electrochromic applications

    Science.gov (United States)

    Boyadjiev, S. I.; Stefan, N.; Szilágyi, I. M.; Mihailescu, N.; Visan, A.; Mihailescu, I. N.; Stan, G. E.; Besleaga, C.; Iliev, M. T.; Gesheva, K. A.

    2017-01-01

    Tungsten trioxide (WO3) is a widely studied material for electrochromic applications. The structure, morphology and optical properties of WO3 thin films, grown by matrix assisted pulsed laser evaporation (MAPLE) from monoclinic WO3 nano-sized particles, were investigated for their possible application as electrochromic layers. A KrF* excimer (λ=248 nm, ζFWHM=25 ns) laser source was used in all experiments. The MAPLE deposited WO3 thin films were studied by atomic force microscopy (AFM), grazing incidence X-ray diffraction (GIXRD) and Fourier transform infrared spectroscopy (FTIR). Cyclic voltammetry measurements were also performed, and the coloring and bleaching were observed. The morpho-structural investigations disclosed the synthesis of single-phase monoclinic WO3 films consisting of crystalline nano-grains embedded in an amorphous matrix. All thin films showed good electrochromic properties, thus validating application of the MAPLE deposition technique for the further development of electrochromic devices.

  2. Morphological parameters of the norway maple small undergrowthin forests of the Novgorod-Sivers’k Polissia

    Directory of Open Access Journals (Sweden)

    V. G. Skliar

    2012-02-01

    Full Text Available The size characteristics of the Norway maple small undergrowth in different association groups of the forests of Novgorod-Sivers’k Polissia are аnalyzed. As the trophicity of soil increases the values of static metric and dynamic morphoparameters of the undergrowth upsurge. And on the contrary, the values reduced with the growth of the forest overstory density and the projective cover of the herb-shrub layer. It is shown that in different plant communities the Norway maple undergrowth is characterised by specific morphological structure. The communal habitat of the group of Querceta convallariosa associations conforms with the parameters of ecocoenotical optimum, which conditions are most favourable for successful growth of the maple young generation.

  3. Development of seedlings of watermelon cv. Crimson Sweet irrigated with biosaline water

    Directory of Open Access Journals (Sweden)

    José E. S. B. da Silva

    2015-09-01

    Full Text Available ABSTRACTThe limited access and the scarcity of good quality water for agriculture are some of the major problems faced in agricultural areas, particularly in arid and semiarid regions. The aim of this study was to evaluate the quality of watermelon seedlings (cv. Crimson Sweet, irrigated with different concentrations of biosaline water of fish culture. The experimental design was completely randomized with five treatments, corresponding to biosaline water at different concentrations (0, 33, 50, 67 and 100%, and four replicates of 108 seedlings. Watermelon seeds were sown in plastic trays filled with commercial substrate and irrigated with different solutions of biosaline water. Seedlings were harvested for biometric analysis at 14, 21 and 28 days after sowing. The use of biosaline water did not affect emergence and establishment of seedlings until 14 days after sowing, the period recommended for transplantation. However, the use of biosaline water affected the development of seedlings with longer exposure time.

  4. Growth of thin films of low molecular weight proteins by matrix assisted pulsed laser evaporation (MAPLE)

    DEFF Research Database (Denmark)

    Matei, Andreea; Schou, Jørgen; Constantinescu, C.;

    2011-01-01

    Thin films of lysozyme and myoglobin grown by matrix assisted pulsed laser evaporation (MAPLE) from a water ice matrix have been investigated. The deposition rate of these two low molecular weight proteins (lysozyme: 14307 amu and myoglobin: 17083 amu) exhibits a maximum of about 1–2 ng/cm2 per...

  5. In vivo neuroprotective effect of L-carnitine against oxidative stress in maple syrup urine disease

    NARCIS (Netherlands)

    Mescka, Caroline; Moraes, Tarsila; Rosa, Andrea; Mazzola, Priscila; Piccoli, Bruna; Jacques, Carlos; Dalazen, Giovana; Coelho, Juliana; Cortes, Marcelo; Terra, Melaine; Regla Vargas, Carmen; Dutra-Filho, Carlos S

    2011-01-01

    Maple syrup urine disease (MSUD) is an autosomal recessive inborn error of metabolism caused by deficiency of the activity of the mitochondrial enzyme complex branched-chain α-keto acid dehydrogenase (BCKAD) leading to accumulation of the branched-chain amino acids (BCAA) leucine, isoleucine and val

  6. Differential impacts of calcium and aluminum treatments on sugar maple and American beech growth dynamics

    Science.gov (United States)

    Joshua M. Halman; Paul G. Schaberg; Gary J. Hawley; Christopher F. Hansen; Timothy J. Fahey

    2015-01-01

    Acid deposition induced losses of calcium (Ca) from northeastern forests have had negative effects on forest health for decades, including the mobilization of potentially phytotoxic aluminum (Al) from soils. To evaluate the impact of changes in Ca and Al availability on sugar maple (Acer saccharum Marsh.) and American beech (Fagus...

  7. First Record of Eutypella parasitica on Maples in Urban Area in Croatia

    Directory of Open Access Journals (Sweden)

    Dario Ivić

    2017-01-01

    Full Text Available Background and Purpose: Eutypella parasitica, a plant pathogenic fungus attacking maples (Acer spp. was detected for the first time in Croatia in 2007. From 2007 to 2014, it was found only in forests, on several trees in Hum na Sutli, near Slovenian border. In 2015, the presence of Eutypella parasitica was monitored for the first time in urban areas. Materials and Methods: Within the official survey programme, 23 visual surveys were conducted and 24 samples were collected and analysed for the presence of fungi. E. parasitica was found in Bundek Park in Zagreb. Typical symptoms of Eutypella canker were detected on two field maples (Acer campestre and two boxelder maples (Acer negundo. Twelve isolates were collected from symptomatic trees. Conclusions: Eleven out of twelve isolates from four trees were confirmed as E. parasitica by species-specific polymerase chain reaction. This is the first report of E. parasitica in Zagreb, the first record of E. parasitica in Croatia outside forests, as well as a record of a new host species in Croatia, boxelder maple (A. negundo. Introduction pathway of E. parasitica in Zagreb remains unknown.

  8. Evidence for oxidative stress in sugar maple stands growing on acidic, nutrient imbalanced forest soils.

    Science.gov (United States)

    Clair, Samuel B St; Carlson, John E; Lynch, Jonathan P

    2005-09-01

    Soil acidification and the disruption of nutrient cycles appear to be important factors that weaken sugar maple resistance to both abiotic and biotic stresses and predispose it to decline symptoms. Although connections between edaphic stress and decline symptoms have been identified, very little is known about the physiological and biochemical mechanisms that underlie this relationship. In this study, we tested the hypothesis that foliar nutrient imbalances impair the photosynthetic apparatus of sugar maple through oxidative stress. We examined leaf nutrition, photosynthesis and antioxidant enzyme activity (a biomarker of oxidative stress) from early June to late August in three-paired overstory sugar maple stands on Pennsylvania's Allegheny Plateau that contrast in soil nutrient availability according to slope position. Beginning in early June, trees on upper slopes (nutrient-poor) had significantly lower foliar Ca and Mg concentrations and significantly higher foliar Mn concentrations than trees on lower slopes. These differences increased throughout summer peaking in late August. Photosynthesis and antioxidant enzyme activity closely reflected changes in foliar nutrient status throughout the summer. In the latter half of the summer, leaf gas exchange and chlorophyll content were significantly lower and antioxidant enzyme activity was significantly higher in stands on upper slope soils. At the end of August, leaf nutrient imbalances corresponded with lower rates of photosynthesis and higher antioxidant enzyme activity, suggesting that foliar nutrient imbalances may impair sugar maple function through mechanisms of oxidative stress.

  9. The Effects of Maple Integrated Strategy on Engineering Technology Students' Understanding of Integral Calculus

    Science.gov (United States)

    Salleh, Tuan Salwani; Zakaria, Effandi

    2016-01-01

    The objective of this research is to investigate the effectiveness of a learning strategy using Maple in integral calculus. This research was conducted using a quasi-experimental nonequivalent control group design. One hundred engineering technology students at a technical university were chosen at random. The effectiveness of the learning…

  10. HBFTrans2: A Maple Package to Construct Hirota Bilinear Form for Nonlinear Equations

    Institute of Scientific and Technical Information of China (English)

    YANG Xu-Dong; RUAN Hang-Yu

    2011-01-01

    An improved algorithm for symbolic computation of Hirota bilinear form of nonlinear equations by a logarithm transformation is presented.The improved algorithm is more efficient by using the property of Hirota-D operator.The software package HBFTrans2 is written in Maple and its running efficiency is tested by a variety of soliton equations.

  11. Characterization of lysozyme films produced by matrix assisted pulsed laser evaporation (MAPLE)

    DEFF Research Database (Denmark)

    Purice, Andreea; Schou, Jørgen; Kingshott, Peter

    2007-01-01

    Thin lysozyme films of thickness up to more than 100 nm have been produced in a dry environment by MAPLE (matrix assisted pulsed laser evaporation) from a water ice matrix. Analysis of the films demonstrates that a significant part of the lysozyme molecules is transferred to the substrate without...

  12. Algorithms for the extension of precise and imprecise conditional probability assessments: an implementation with maple V

    Directory of Open Access Journals (Sweden)

    Veronica Biazzo

    2000-05-01

    Full Text Available In this paper, we illustrate an implementation with Maple V of some procedures which allow to exactly propagate precise and imprecise probability assessments. The extension of imprecise assessments is based on a suitable generalization of the concept of coherence of de Finetti. The procedures described are supported by some examples and relevant cases.

  13. Carbon content variation in boles of mature sugar maple and giant sequoia.

    Science.gov (United States)

    Lamlom, Sabah H; Savidge, Rodney A

    2006-04-01

    At present, a carbon (C) content of 50% (w/w) in dry wood is widely accepted as a generic value; however, few wood C measurements have been reported. We used elemental analysis to investigate C content per unit of dry matter and observed that it varied both radially and vertically in boles of two old-growth tree species: sugar maple (Acer saccharum Marsh.) and giant sequoia (Sequoiadendron giganteum (Lindl.) Bucholz). In sugar maple there was considerable variation in tree ring widths among four radii for particular annual layers of xylem, revealing that the annual rate of C assimilation differs around the circumference and from the base of each tree to its top, but the observed variation in C content was unrelated to diameter growth rate and strongly related to the calendar year when the wood was formed. Carbon content in sugar maple wood increased in an approximately linear fashion, from 55% across many hundreds of years of heartwood, but it declined abruptly at the sapwood-heartwood boundary and remained lower in all sapwood samples, an indication that heartwood formation involves anabolic metabolism. Factors that may be responsible for the different C contents and trends with age between sugar maple and sequoia trees are considered. Tree-ring data from this study do not support some of the key assumptions made by dendrochronology.

  14. Preliminary results of sugar maple carbohydrate and growth response under vacuum and gravity sap extraction

    Science.gov (United States)

    Mark L. Isselhardt; Timothy D. Perkins; Abby K. van den Berg; Paul G. Schaberg

    2016-01-01

    Recent technological advancements have increased the amount of sugar-enriched sap that can be extracted from sugar maple (Acer saccharum). This pilot study quantified overall sugar removal and the impacts of vacuum (60 cm Hg) and gravity sap extraction on residual nonstructural carbohydrate (NSC) concentrations and on stem and twig growth. Vacuum...

  15. Chemical compositional, biological, and safety studies of a novel maple syrup derived extract for nutraceutical applications.

    Science.gov (United States)

    Zhang, Yan; Yuan, Tao; Li, Liya; Nahar, Pragati; Slitt, Angela; Seeram, Navindra P

    2014-07-16

    Maple syrup has nutraceutical potential given the macronutrients (carbohydrates, primarily sucrose), micronutrients (minerals and vitamins), and phytochemicals (primarily phenolics) found in this natural sweetener. We conducted compositional (ash, fiber, carbohydrates, minerals, amino acids, organic acids, vitamins, phytochemicals), in vitro biological, and in vivo safety (animal toxicity) studies on maple syrup extracts (MSX-1 and MSX-2) derived from two declassified maple syrup samples. Along with macronutrient and micronutrient quantification, thirty-three phytochemicals were identified (by HPLC-DAD), and nine phytochemicals, including two new compounds, were isolated and identified (by NMR) from MSX. At doses of up to 1000 mg/kg/day, MSX was well tolerated with no signs of overt toxicity in rats. MSX showed antioxidant (2,2-diphenyl-1-picrylhydrazyl (DPPH) assay) and anti-inflammatory (in RAW 264.7 macrophages) effects and inhibited glucose consumption (by HepG2 cells) in vitro. Thus, MSX should be further investigated for potential nutraceutical applications given its similarity in chemical composition to pure maple syrup.

  16. Efficacy of stem injection treatments on striped maple in central West Virginia

    Science.gov (United States)

    Jeffrey D. Kochenderfer; James N. Kochenderfer

    2008-01-01

    Hack-and-squirt injection treatments were applied to individual striped maple (Acer pennsylvanicum L.) stems and to the largest stem in sprout clumps in a 25-year-old clearcut in central West Virginia to evaluate seasonal efficacy of imazapyr as Arsenal (28.7%) and glyphosate as Glypro Plus (41.0%) in water carriers. Complete control of injected...

  17. Maple (Computer Algebra System) in Teaching Pre-Calculus: Example of Absolute Value Function

    Science.gov (United States)

    Tuluk, Güler

    2014-01-01

    Modules in Computer Algebra Systems (CAS) make Mathematics interesting and easy to understand. The present study focused on the implementation of the algebraic, tabular (numerical), and graphical approaches used for the construction of the concept of absolute value function in teaching mathematical content knowledge along with Maple 9. The study…

  18. Symbiotic maple saps minimize disruption of the mice intestinal microbiota after oral antibiotic administration.

    Science.gov (United States)

    Hammami, Riadh; Ben Abdallah, Nour; Barbeau, Julie; Fliss, Ismail

    2015-01-01

    This study was undertaken to evaluate the in vivo impact of new symbiotic products based on liquid maple sap or its concentrate. Sap and concentrate, with or without inulin (2%), were inoculated with Bifidobacterium lactis Bb12 and Lactobacillus rhamnosus GG valio at initial counts of 2-4 × 10(8) cfu mL(-1). The experiments started with intra-gastric administration of antibiotic (kanamycin 40 mg in 0.1 cc) (to induce microbiota disturbance and/or diarrhea) to 3-to-5-week-old C57BL/6 female mice followed by a combination of prebiotic and probiotics included in the maple sap or its concentrate for a week. The combination inulin and probiotics in maple sap and concentrate appeared to minimize the antibiotic-induced breakdown of mice microbiota with a marked effect on bifidobacterium and bacteroides levels, thus permitting a more rapid re-establishment of the baseline microbiota levels. Results suggest that maple sap and its concentrate represent good candidates for the production of non-dairy functional foods.

  19. Movement disorders in adult surviving patients with maple syrup urine disease.

    Science.gov (United States)

    Carecchio, Miryam; Schneider, Susanne A; Chan, Heidi; Lachmann, Robin; Lee, Philip J; Murphy, Elaine; Bhatia, Kailash P

    2011-06-01

    Maple syrup urine disease is a rare metabolic disorder caused by mutations in the branched-chain α-keto acid dehydrogenase complex gene. Patients generally present early in life with a toxic encephalopathy because of the accumulation of the branched-chain amino acids leucine, isoleucine, and valine and the corresponding ketoacids. Movement disorders in maple syrup urine disease have typically been described during decompensation episodes or at presentation in the context of a toxic encephalopathy, with complete resolution after appropriate dietary treatment. Movement disorders in patients surviving childhood are not well documented. We assessed 17 adult patients with maple syrup urine disease (mean age, 27.5 years) with a special focus on movement disorders. Twelve (70.6%) had a movement disorder on clinical examination, mainly tremor and dystonia or a combination of both. Parkinsonism and simple motor tics were also observed. Pyramidal signs were present in 11 patients (64.7%), and a spastic-dystonic gait was observed in 6 patients (35.2%). In summary, movement disorders are common in treated adult patients with maple syrup urine disease, and careful neurological examination is advisable to identify those who may benefit from specific therapy. © 2011 Movement Disorder Society.

  20. Stem girdling manipulates leaf sugar concentrations and anthocyanin expression in sugar maples trees during autumn

    Science.gov (United States)

    P.F. Murakami; P.G. Schaberg; J.B. Shane

    2008-01-01

    To better understand the effects of sugar accumulation on red color development of foliage during autumn, we compared carbohydrate concentration, anthocyanin expression and xylem pressure potential of foliage on girdled versus non-girdled (control) branches of 12 mature, open-grown sugar maple (Acer saccharum Marsh.) trees. Half of the study trees...

  1. Occurrence of poly-winged fruits on cultivated sycamore maples - Acer pseudoplatanus L

    Directory of Open Access Journals (Sweden)

    Ivetić Vladan

    2003-01-01

    Full Text Available The occurrence of polycarpous fruits on six out of 100 sycamore maples, i e. with 3, 4 and 8 fruits on one carpophore is described. Eight-carpous fruits have not been recorded to date in the region of the Serbia and Montenegro, and wider. The cause of the development of polycarpous fruits has been hypothesized.

  2. Surface morphology of thin lysozyme films produced by matrix-assisted pulsed laser evaporation (MAPLE)

    DEFF Research Database (Denmark)

    Purice, Andreea; Schou, Jørgen; Pryds, Nini;

    2007-01-01

    Thin films of the protein, lysozyme, have been deposited by the matrix-assisted pulsed laser evaporation (MAPLE) technique. Frozen targets of 0.3-1.0 wt.% lysozyme dissolved in ultrapure water were irradiated by laser light at 355 mn with a fluence of 2 J/cm(2). The surface quality of the thin ly...

  3. MODELING IN MAPLE AS THE RESEARCHING MEANS OF FUNDAMENTAL CONCEPTS AND PROCEDURES IN LINEAR ALGEBRA

    Directory of Open Access Journals (Sweden)

    Vasil Kushnir

    2016-05-01

    Full Text Available The article is devoted to binary technology and "fundamental training technology." Binary training refers to the simultaneous teaching of mathematics and computer science, for example differential equations and Maple, linear algebra and Maple. Moreover the system of traditional course of Maple is not performed. The use of the opportunities of Maple-technology in teaching mathematics is based on the following fundamental concepts of computer science as an algorithm, program, a linear program, cycle, branching, relative operators, etc. That’s why only a certain system of command operators in Maple is considered. They are necessary for fundamental concepts of linear algebra and differential equations studying in Maple-environment. Relative name - "the technology of fundamental training" reflects the study of fundamental mathematical concepts and procedures that express the properties of these concepts in Maple-environment. This article deals with the study of complex fundamental concepts of linear algebra (determinant of the matrix and algorithm of its calculation, the characteristic polynomial of the matrix and the eigenvalues of matrix, canonical form of characteristic matrix, eigenvectors of matrix, elementary divisors of the characteristic matrix, etc., which are discussed in the appropriate courses briefly enough, and sometimes are not considered at all, but they are important in linear systems of differential equations, asymptotic methods for solving differential equations, systems of linear equations. Herewith complex and voluminous procedures of finding of these linear algebra concepts embedded in Maple can be performed as a result of a simple command-operator. Especially important issue is building matrix to canonical form. In fact matrix functions are effectively reduced to the functions of the diagonal matrix or matrix in Jordan canonical form. These matrices are used to rise a square matrix to a power, to extract the roots of the n

  4. The influence of seedling density in containers on morphological characteristics of European beech

    Directory of Open Access Journals (Sweden)

    Wrzesiński Piotr

    2015-09-01

    Full Text Available This study examines the influence on growth parameters, in particular the morphological features of the root system, of 1-year-old European beech seedlings cultivated in containers with two different densities. The experiment was conducted in the container nursery in Skierdy (Forest District of Jabłonna in spring 2011. After 10 months of cultivation in Hiko polyethylene containers, above- and below-ground parts of the seedlings were measured. The measurements of the root system were conducted with a scanner and the WinRHIZO software. No influence due to the seedling density on either shoot height or thickness was observed, but instead the research showed that different seedling densities affected the development of root systems. The mean root thickness and dry mass of the European beech seedlings were significantly higher at the lower density. The influence of seedling density on the development of root mass deserves special attention as it is the most important factor affecting future growth of the seedlings during cultivation. This tendency also suggests that the amount of nutrients allocated to shoot development may be higher in order to improve the efficiency of photosynthesis. At both densities, differences in biomass accumulation affected the root-toshoot ratio. In seedlings cultivated at the lower density, the increased dry root matter of the seedlings resulted in a significant increase in the root-to-shoot ratio. This may cause a potential growth advantage of these seedlings after they are planted and may thus result in a more productive cultivation.

  5. Potential production of Aspidosperma cylindrocarpon seedlings viarescue seedlings

    Directory of Open Access Journals (Sweden)

    Nathália Ferreira e Silva

    Full Text Available ABSTRACT: Translocation of rare populations is regarded as the last resort for the conservation of species whose habitat destruction is imminent. The objective of the present study was to evaluate the effect of two height classes and three leaf reduction intensities on growth and increases in height, stem diameter, survival, and new leaf production in seedlings of Aspidosperma cylindrocarpon (peroba obtained via rescue seedlings in a remnant of tropical semi deciduous forest. We recovered 240 individuals that were divided into two height classes (Class I-5 to 15cm and Class II-20 to 35cm and subjected to three leaf reduction intensities (0%, 50%, and 100%, which were then transported to a shade house with 50% light reduction. Measurements of height, stem diameter, and new leaf production were collected 8 times at 0, 15, 60, 75, 90, 105, 120, and 135 days, and survival rate was measured at day 135. The average survival rate was 82.9%; 77.5% for one Class I (5-15cm and 88.3% for Class II (20-35cm. Higher seedling growth was observed for the 0% leaf reduction treatment in both height classes. The leaves insertion were greater in the 100% cuts, with a decrease observed over time. It is advisable to restore A. cylindrocarpon seedlings in two height classes owing to the high survival rate, leaf appearance, and growth reported in the present study. The no-leaf reduction treatment (0% is the most viable alternative for the production of A. cylindrocarpon seedlings, via rescue seedlings.

  6. Radiation effects on Brassica seeds and seedlings

    Science.gov (United States)

    Deoli, Naresh; Hasenstein, Karl H.

    2016-07-01

    Space radiation consists of high energy charged particles and affects biological systems, but because of its stochastic, non-directional nature is difficult to replicate on Earth. Radiation damages biological systems acutely at high doses or cumulatively at low doses through progressive changes in DNA organization. These damages lead to death or cause of mutations. While radiation biology typically focuses on mammalian or human systems, little is known as to how radiation affects plants. In addition, energetic ion beams are widely used to generate new mutants in plants considering their high-LET (Linear Energy Transfer) as compared to gamma rays and X-rays. Understanding the effect of ionizing radiation on plant provides a basis for studying effects of radiation on biological systems and will help mitigate (space) radiation damage in plants. We exposed dry and imbibed Brassica rapa seeds and seedling roots to proton beams of varying qualities and compared the theoretical penetration range of different energy levels with observable growth response. We used 1, 2 and 3 MeV protons in air at the varying fluences to investigate the effect of direct irradiation on the seeds (1012 - 1015 ions/cm2) and seedlings (1013 ions/cm2). The range of protons in the tissue was calculated using Monte-Carlo based SRIM (Stopping and Range of Ions in Matter) software. The simulation and biological results indicate that ions did not penetrate the tissue of dry or hydrated seeds at all used ion energies. Therefore the entire energy was transferred to the treated tissue. Irradiated seeds were germinated vertically under dim light and roots growth was observed for two days after imbibition. The LD50 of the germination was about 2×1014 ions/cm2 and about 5×1014 ions/cm2 for imbibed and dry seeds, respectively. Since seedlings are most sensitive to gravity, the change in gravitropic behavior is a convenient means to assess radiation damage on physiological responses other than direct tissue

  7. Fatores que afetam a germinação de sementes e emergência de plântulas de arruda (Ruta graveolens L. Factors affecting seed germination and seedling emergence in rue (Ruta graveolens L.

    Directory of Open Access Journals (Sweden)

    O.M. Yamashita

    2009-01-01

    Full Text Available Ruta graveolens L., também conhecida com arruda, é planta originária do sul da Europa, cultivada no Brasil e em outros países como planta medicinal, muito utilizada em rituais religiosos. Tendo em vista que a germinação constitui um fator primordial para que a semente possa gerar uma planta vigorosa e com alto potencial produtivo, o presente trabalho teve como objetivo avaliar a resposta germinativa de sementes para arruda sob condições de temperatura, luminosidade, estresse hídrico e salino e emergência de plântulas em diferentes profundidades de semeadura. Sementes de Ruta graveolens são indiferentes à luz, germinando melhor em temperatura constante de 25ºC ou alterna (20-30ºC. Os potenciais osmóticos induzidos por manitol a partir de -0,4MPa e por NaCl a partir de -0,8MPa influenciam negativamente o processo germinativo. Maiores percentuais de plântulas são obtidas quando a espécie é semeada na superfície do substrato.Ruta graveolens L., also known as rue, is from the south of Europe, cultivated in Brazil and other countries as a medicinal plant greatly used in religious rituals. Since germination is essential for the seed to generate a vigorous plant of high productive potential, this work aimed to evaluate the germinative response of rue seeds under different temperatures, luminosity conditions, and water and salt stress, besides seedling emergence at different sowing depths. Ruta graveolens L. seeds are indifferent to light, better germinating at constant temperature of 25ºC or alternated temperature (20-30ºC. The osmotic potentials induced by mannitol from -0.4MPa and by NaCl from -0.8MPa negatively influenced the germination process. Higher seedling percentages are obtained when the species is sown on the substratum surface.

  8. Gene expression in plant lipid metabolism in Arabidopsis seedlings.

    Directory of Open Access Journals (Sweden)

    An-Shan Hsiao

    Full Text Available Events in plant lipid metabolism are important during seedling establishment. As it has not been experimentally verified whether lipid metabolism in 2- and 5-day-old Arabidopsis thaliana seedlings is diurnally-controlled, quantitative real-time PCR analysis was used to investigate the expression of target genes in acyl-lipid transfer, β-oxidation and triacylglycerol (TAG synthesis and hydrolysis in wild-type Arabidopsis WS and Col-0. In both WS and Col-0, ACYL-COA-BINDING PROTEIN3 (ACBP3, DIACYLGLYCEROL ACYLTRANSFERASE1 (DGAT1 and DGAT3 showed diurnal control in 2- and 5-day-old seedlings. Also, COMATOSE (CTS was diurnally regulated in 2-day-old seedlings and LONG-CHAIN ACYL-COA SYNTHETASE6 (LACS6 in 5-day-old seedlings in both WS and Col-0. Subsequently, the effect of CIRCADIAN CLOCK ASSOCIATED1 (CCA1 and LATE ELONGATED HYPOCOTYL (LHY from the core clock system was examined using the cca1lhy mutant and CCA1-overexpressing (CCA1-OX lines versus wild-type WS and Col-0, respectively. Results revealed differential gene expression in lipid metabolism between 2- and 5-day-old mutant and wild-type WS seedlings, as well as between CCA1-OX and wild-type Col-0. Of the ACBPs, ACBP3 displayed the most significant changes between cca1lhy and WS and between CCA1-OX and Col-0, consistent with previous reports that ACBP3 is greatly affected by light/dark cycling. Evidence of oil body retention in 4- and 5-day-old seedlings of the cca1lhy mutant in comparison to WS indicated the effect of cca1lhy on storage lipid reserve mobilization. Lipid profiling revealed differences in primary lipid metabolism, namely in TAG, fatty acid methyl ester and acyl-CoA contents amongst cca1lhy, CCA1-OX, and wild-type seedlings. Taken together, this study demonstrates that lipid metabolism is subject to diurnal regulation in the early stages of seedling development in Arabidopsis.

  9. Soil solution and sugar maple response to NH(4)NO (3) additions in a base-poor northern hardwood forest of Québec, Canada.

    Science.gov (United States)

    Moore, Jean-David; Houle, Daniel

    2009-08-01

    Nitrogen additions (NH4NO3) at rates of three- and ten-fold ambient atmospheric deposition (8.5 kg ha(-1) year(-1)) were realised in an acid- and base-poor northern hardwood forest of Québec, Canada. Soil solution chemistry, foliar chemistry, crown dieback and basal area growth of sugar maple (Acer saccharum Marsh.) were measured. Except for a transitory increase of NO3 and NH4 concentrations, there was no persistent increase in their level in soil solution 3 years after N treatments, with the exception of one plot out of three, that received the highest N addition, beginning to show persistent and high NO3 concentrations after 2 years of N additions. Three years of N additions have significantly increased the N DRIS index of sugar maple but not N foliar concentration. Potassium, Ca and Mn foliar concentrations, as well as P and Ca DRIS indices, decreased in treated plots after 3 years. No treatment effect was observed for basal area growth and dieback rate. One unexpected result was the significant decrease in foliar Ca even in the treated plots that received low N rates, despite the absence of significant NO3-induced leaching of Ca. The mechanism responsible for the decrease in foliar Ca is not known. Our results, however, clearly demonstrate that increased N deposition at sites with low base saturation may affect Ca nutrition even when clear signs of N saturation are not observed.

  10. Effect of Fertilization on the Morphological Development of European Hophormbeam (Ostrya carpinifolia Scop. Seedlings

    Directory of Open Access Journals (Sweden)

    Şemsettin Kulaç

    2016-10-01

    Full Text Available In this study, in order to help the mass production of seedlings, the effect of fertilization on the morphological development of hornbeam leafy European hophornbeam (Ostry carpinifolia Scop seedlings were investigated. For this, seedlings, which were obtained from the seeds coming from different European hophornbeam populations (Düzce-Yığılca, Antalya-Finike, Antalya-Akseki, Kastamonu-Şehdağ ve Adana-Saimbeyli from various parts of Turkey, were used. European hophornbeam seedlings were treated with different fertilizers, including urea, ammonium sulphate, compound fertilizer 15-15-15 and 20-20-0, and 6-9 months Osmocote release fertilizer, and effects of these fertilizers on the morphological characters were investigated. Fertilization contained the same amount of nitrogen, and was made in three different ways; (1 mixing with habitat, (2 topical application and (3 liquid application. The development of germinated European hophornbeam seeds, which were spring-sowed in the same medium were monitored during the vegetation period. At the end of vegetation period, seedlings were removed from the soil and morphological characteristics of root (seedling length, root collar diameter, root length, fresh root and stem weight of the seedlings, dried root and stem weight of the seedlings and bud number were measured. As a result, it was observed that fertilization positively affects the development of seedlings and depending on the fertilization type the seedlings of European hophornbeam populations were found to exhibit different improvements/growing. In addition, 6-9 months Osmocote release fertilizers were determined to be the best fertilizers affecting the morphological (diameter and height development of European hophornbeam populations effectively, and among the populations, Düzce and Kastamonu populations showed the best improvement/growing.

  11. Biogeochemical features of maple and dandelion in Eastern Administrative District of Moscow

    Science.gov (United States)

    Vlasov, Dmitry

    2014-05-01

    Today more than half of world population and 73% of population in Russia live in cities. Moscow is the only one megacity in Russia with the population more than 11 million. The main source of technogenic impact in Moscow is transport. Plants can be used as indicators of urban environment heavy metals and metalloids (HM) pollution. Large scale biogeochemical research was done in Eastern Administrative District of Moscow. Apart from transport there are many industrial sources of pollution: metalworking, mechanical engineering, chemical, energetic and incinerator. This study focuses on detection of HM composition of woody plant leaves (maple - Acer platanoides) and herbaceous species leaves (dandelion - Taraxacum officinale). Plant material was collected on a regular greed with a step of 500-700 m. Background plants were sampled at 40 km west away from the city. Determination of Fe, Mn, Mo, Cd, Pb, Zn, Cu, As, Sb in plants was done using atomic absorption spectrometry after washing, drying and digestion with HNO3+H2O2. It was revealed that dandelion accumulates (index - concentration factors CF relatively background) Mo13Fe6Pb5Cd4.5As4Sb3, while maple Sb13As5.5Fe3Mo2Pb,Zn1.5. Geochemical specialization of plants in functional zones (industrial, transport, recreational, agricultural, residential areas with high-, middle- and low-rise buildings) was identified. The highest CF were determined for Mo in dandelion of all zones except industrial. In which the most accumulated elements are Fe and Mo, as well as Pb10As6Sb5Cu2. Arsenic is accumulated by dandelion in all zones. Copper is not concentrated by herbaceous species because of antagonism between Mo and Cu. The highest CF were determined for HM in maple of industrial zone. There trees concentrate Sb and As9Fe7Mo6Pb3Zn2. In the other zones levels of CF are lower in 2-5 times. Dandelion and maple don't accumulate Mn because of antagonism between Zn, Mo and Mn. Urban plants condition is estimated by the ratio between

  12. Road and Street Centerlines, Maple Canyon, Published in 2007, 1:24000 (1in=2000ft) scale, Iron County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — , published at 1:24000 (1in=2000ft) scale, was produced all or in part from Other information as of 2007. It is described as 'Maple Canyon'. The extent of these...

  13. Winter climate change and fine root biogenic silica in sugar maple trees (Acer saccharum): Implications for silica in the Anthropocene

    Science.gov (United States)

    Maguire, Timothy J.; Templer, Pamela H.; Battles, John J.; Fulweiler, Robinson W.

    2017-03-01

    Winter temperatures are projected to increase over the next century, leading to reductions in winter snowpack and increased frequency of soil freezing in many northern forest ecosystems. Here we examine biogenic silica (BSi) concentrations in sugar maple (Acer saccharum) fine roots collected from a snow manipulation experiment at Hubbard Brook Experimental Forest (New Hampshire, USA). Increased soil freezing significantly lowered the BSi content of sugar maple fine roots potentially decreasing their capacity to take up water and dissolved nutrients. The reduced silica uptake (8 ± 1 kmol silica km-2) by sugar maple fine roots is comparable to silica export from temperate forest watersheds. We estimate that fine roots account for 29% of sugar maple BSi, despite accounting for only 4% of their biomass. These results suggest that increased frequency of soil freezing will reduce silica uptake by temperate tree roots, thereby changing silica availability in downstream receiving waters.

  14. The Evolutionary History of MAPL (Mitochondria-Associated Protein Ligase) and Other Eukaryotic BAM/GIDE Domain Proteins.

    Science.gov (United States)

    Wideman, Jeremy G; Moore, Blake P

    2015-01-01

    MAPL (mitochondria-associated protein ligase, also called MULAN/GIDE/MUL1) is a multifunctional mitochondrial outer membrane protein found in human cells that contains a unique BAM (beside a membrane) domain and a C-terminal RING-finger domain. MAPL has been implicated in several processes that occur in animal cells such as NF-kB activation, innate immunity and antiviral signaling, suppression of PINK1/parkin defects, mitophagy in skeletal muscle, and caspase-dependent apoptosis. Previous studies demonstrated that the BAM domain is present in diverse organisms in which most of these processes do not occur, including plants, archaea, and bacteria. Thus the conserved function of MAPL and its BAM domain remains an open question. In order to gain insight into its conserved function, we investigated the evolutionary origins of MAPL by searching for homologues in predicted proteomes of diverse eukaryotes. We show that MAPL proteins with a conserved BAM-RING architecture are present in most animals, protists closely related to animals, a single species of fungus, and several multicellular plants and related green algae. Phylogenetic analysis demonstrated that eukaryotic MAPL proteins originate from a common ancestor and not from independent horizontal gene transfers from bacteria. We also determined that two independent duplications of MAPL occurred, one at the base of multicellular plants and another at the base of vertebrates. Although no other eukaryote genome examined contained a verifiable MAPL orthologue, BAM domain-containing proteins were identified in the protists Bigelowiella natans and Ectocarpus siliculosis. Phylogenetic analyses demonstrated that these proteins are more closely related to prokaryotic BAM proteins and therefore likely arose from independent horizontal gene transfers from bacteria. We conclude that MAPL proteins with BAM-RING architectures have been present in the holozoan and viridiplantae lineages since their very beginnings. Our work paves

  15. The Evolutionary History of MAPL (Mitochondria-Associated Protein Ligase and Other Eukaryotic BAM/GIDE Domain Proteins.

    Directory of Open Access Journals (Sweden)

    Jeremy G Wideman

    Full Text Available MAPL (mitochondria-associated protein ligase, also called MULAN/GIDE/MUL1 is a multifunctional mitochondrial outer membrane protein found in human cells that contains a unique BAM (beside a membrane domain and a C-terminal RING-finger domain. MAPL has been implicated in several processes that occur in animal cells such as NF-kB activation, innate immunity and antiviral signaling, suppression of PINK1/parkin defects, mitophagy in skeletal muscle, and caspase-dependent apoptosis. Previous studies demonstrated that the BAM domain is present in diverse organisms in which most of these processes do not occur, including plants, archaea, and bacteria. Thus the conserved function of MAPL and its BAM domain remains an open question. In order to gain insight into its conserved function, we investigated the evolutionary origins of MAPL by searching for homologues in predicted proteomes of diverse eukaryotes. We show that MAPL proteins with a conserved BAM-RING architecture are present in most animals, protists closely related to animals, a single species of fungus, and several multicellular plants and related green algae. Phylogenetic analysis demonstrated that eukaryotic MAPL proteins originate from a common ancestor and not from independent horizontal gene transfers from bacteria. We also determined that two independent duplications of MAPL occurred, one at the base of multicellular plants and another at the base of vertebrates. Although no other eukaryote genome examined contained a verifiable MAPL orthologue, BAM domain-containing proteins were identified in the protists Bigelowiella natans and Ectocarpus siliculosis. Phylogenetic analyses demonstrated that these proteins are more closely related to prokaryotic BAM proteins and therefore likely arose from independent horizontal gene transfers from bacteria. We conclude that MAPL proteins with BAM-RING architectures have been present in the holozoan and viridiplantae lineages since their very beginnings

  16. Analysis of plastic residues in maple sap and syrup collected from tubing systems sanitized with isopropyl alcohol.

    Science.gov (United States)

    Lagacé, Luc; Charron, Carmen; Sadiki, Mustapha

    2017-05-01

    A plastic tubing system operated under vacuum is usually used to collect sap from maple trees during spring time to produce maple syrup. This system is commonly sanitized with isopropyl alcohol (IPA) to remove microbial contamination colonizing the system during the sugar season. Questions have been raised whether IPA would contribute to the leaching of plastic residues in maple sap and syrup coming from sanitized systems. First, an extraction experiment was performed in the lab on commercial plastic tubing materials that were submitted to IPA under harsh conditions. The results of the GC-MS analysis revealed the presence of many compounds that served has target for further tests. Secondly, tests were done on early and mid-season maple sap and syrup coming from many sugarbushes using IPA or not to determine potential concentrations of plastic residues. Results obtained from sap and syrup samples showed that no quantifiable (sap run used as a rinse solution to be discarded before the season start and that were coming from non sanitized or IPA sanitized systems, showed quantifiable concentrations of chemical residue such as ultraviolet protector (octabenzone). These results show that IPA can be safely used to sanitize maple sap collection system in regards to the leaching of plastic residues in maple sap and syrup and reinforced the need to thoroughly rinse the tubing system at the beginning of the season for both sanitized and non sanitized systems.

  17. Seedling-herbivore interactions: insights into plant defence and regeneration patterns.

    Science.gov (United States)

    Barton, Kasey E; Hanley, Mick E

    2013-08-01

    Herbivores have the power to shape plant evolutionary trajectories, influence the structure and function of vegetation, devastate entire crops, or halt the spread of invasive weeds, and as a consequence, research into plant-herbivore interactions is pivotal to our understanding of plant ecology and evolution. However, the causes and consequences of seedling herbivory have received remarkably little attention, despite the fact that plants tend to be most susceptible to herbivory during establishment, and this damage can alter community composition and structure. In this Viewpoint article we review why herbivory during early plant ontogeny is important and in so doing introduce an Annals of Botany Special Issue that draws together the latest work on the topic. In a synthesis of the existing literature and a collection of new studies, we examine several linked issues. These include the development and expression of seedling defences and patterns of selection by herbivores, and how seedling selection affects plant establishment and community structure. We then examine how disruption of the seedling-herbivore interaction might affect normal patterns of plant community establishment and discuss how an understanding of patterns of seedling herbivory can aid our attempts to restore semi-natural vegetation. We finish by outlining a number of areas where more research is required. These include a need for a deeper consideration of how endogenous and exogenous factors determine investment in seedling defence, particularly for the very youngest plants, and a better understanding of the phylogenetic and biogeographical patterns of seedling defence. There is also much still be to be done on the mechanisms of seedling selection by herbivores, particularly with respect to the possible involvement of volatile cues. These inter-related issues together inform our understanding of how seedling herbivory affects plant regeneration at a time when anthropogenic change is likely to

  18. Proton magnetic resonance spectroscopy reflects metabolic decompensation in maple syrup urine disease

    Energy Technology Data Exchange (ETDEWEB)

    Heindel, W. [Dept. of Diagnostic Radiology, Univ. Koeln (Germany); Kugel, H. [Dept. of Diagnostic Radiology, Univ. Koeln (Germany); Wendel, U. [Children`s Hospital, Univ. Duesseldorf (Germany); Roth, B. [Children`s Hospital, Univ. Koeln (Germany); Benz-Bohm, G. [Dept. of Diagnostic Radiology, Univ. Koeln (Germany)

    1995-06-01

    Using localized proton magnetic resonance spectroscopy ({sup 1}H-MRS), accumulation of branchedchain amino acids (BCAA) and their corresponding 2-oxo acids (BCOA) could be non-invasively demonstrated in the brain of a 9-year-old girl suffering from classical maple syrup urine disease. During acute metabolic decompensation, the compounds caused a signal at a chemical shift of 0.9 ppm which was assigned by in vitro experiments. The brain tissue concentration of the sum of BCAA and BCOA could be estimated as 0.9 mmol/l. Localized {sup 1}H-MRS of the brain appears to be suitable for examining patients suffering from maple syrup urine disease in different metabolic states. (orig.)

  19. MAPLE fabrication of thin films based on kanamycin functionalized magnetite nanoparticles with anti-pathogenic properties

    Science.gov (United States)

    Grumezescu, Valentina; Andronescu, Ecaterina; Holban, Alina Maria; Mogoantă, Laurenţiu; Mogoşanu, George Dan; Grumezescu, Alexandru Mihai; Stănculescu, Anca; Socol, Gabriel; Iordache, Florin; Maniu, Horia; Chifiriuc, Mariana Carmen

    2015-05-01

    In this study we aimed to evaluate the biocompatibility and antimicrobial activity of kanamycin functionalized 5 nm-magnetite (Fe3O4@KAN) nanoparticles thin films deposited by Matrix Assisted Pulsed Laser Evaporation (MAPLE) technique. A laser deposition regime was established in order to stoichiometrically transfer Fe3O4@KAN thin films on silicone and glass substrates. Morphological and physico-chemical properties of powders and coatings were characterized by XRD, TEM, SEM, AFM and IR microscopy (IRM). Our nanostructured thin films have proved efficiency in the prevention of microbial adhesion and mature biofilms development as a result of antibiotic release in its active form. Furthermore, kanamycin functionalized nanostructures exhibit a good biocompatibility, both in vivo and in vitro, demonstrating their potential for implants application. This is the first study reporting the assessment of the in vivo biocompatibility of a magnetite-antimicrobial thin films produced by MAPLE technique.

  20. Optics learning by computing, with examples using Maple, MathCad, Mathematica, and MATLAB

    CERN Document Server

    Moeller, Karl Dieter

    2007-01-01

    This new edition is intended for a one semester course in optics for juniors and seniors in science and engineering; it uses scripts from Maple, MathCad, Mathematica, and MATLAB provide a simulated laboratory where students can learn by exploration and discovery instead of passive absorption. The text covers all the standard topics of a traditional optics course, including: geometrical optics and aberration, interference and diffraction, coherence, Maxwell's equations, wave guides and propagating modes, blackbody radiation, atomic emission and lasers, optical properties of materials, Fourier transforms and FT spectroscopy, image formation, and holography. It contains step by step derivations of all basic formulas in geometrical, wave and Fourier optics. The basic text is supplemented by over 170 files in Maple, MathCad, Mathematica, and MATLAB (many of which are in the text, each suggesting programs to solve a particular problem, and each linked to a topic in or application of optics. The computer files are d...

  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. [Growth, survival and herbivory of seedlings in Brosimum alicastrum (Moraceae), a species from the Neotropical undergrowth].

    Science.gov (United States)

    Ballina-Gómez, H S; Iriarte-Vivar, S; Orellana, R; Santiago, L S

    2008-12-01

    Growth responses, survival, and herbivory, on seedlings of Brosimum alicastrum were studied in a neotropical Mexican forest. We selected 122 seedlings and divided them into three groups assigned to defoliation treatments: control or 0 (n=21), 50 (n=51) and 90% (n=50). Every 4 months during two years we measured seedling growth (in terms of relative growth rate in biomass, leaf area growth, produced leaves and height growth) and survival. In addition, we evaluated every 12 months pathogen damage and insect herbivory using a 2 mm(-2) grid. Separately, we estimated mammal herbivory in 3-month old seedlings that were selected within a plot of 500 m x 10 m (N=1095). Pathogen damage and insect herbivory were evaluated within the same plot in 113 seedlings. We found that 50% defoliated seedlings showed compensatory responses in all growth parameters. Relative growth rate and height growth also had a compensatory response in seedlings at 90% defoliation. Relative growth rate and leaf area growth gradually decreased with time although height growth seedling showed an opposite pattern. Leaves produced were not affected by time. Estimated seedling survival probability increased with defoliation to a maximum of 97%, decreasing at 24 month to 37%. Mammal herbivory was more frequent and severe than herbivory caused by pathogens and insects. In some cases, mammal herbivory produced total defoliation. Compensatory growth in leaf area growth, produced leaves and height growth seedling suggest a synergic compensatory mechanism expressed in a whole-plant growth biomass (relative growth rate). Compensation and survival results suggest trade-offs at the leaf level, such as leaf area growth and produced leaves versus chemical defenses, respectively.

  3. No evidence that chronic nitrogen additions increase photosynthesis in mature sugar maple forests.

    Science.gov (United States)

    Talhelm, A F; Pregitzer, K S; Burton, A J

    2011-10-01

    Atmospheric nitrogen (N) deposition can increase forest growth. Because N deposition commonly increases foliar N concentrations, it is thought that this increase in forest growth is a consequence of enhanced leaf-level photosynthesis. However, tests of this mechanism have been infrequent, and increases in photosynthesis have not been consistently observed in mature forests subject to chronic N deposition. In four mature northern hardwood forests in the north-central United States, chronic N additions (30 kg N ha(-1) yr(-1) as NaNO3 for 14 years) have increased aboveground growth but have not affected canopy leaf biomass or leaf area index. In order to understand the mechanism behind the increases in growth, we hypothesized that the NO3(-) additions increased foliar N concentrations and leaf-level photosynthesis in the dominant species in these forests (sugar maple, Acer saccharum). The NO3(-) additions significantly increased foliar N. However, there was no significant difference between the ambient and +NO3(-) treatments in two seasons (2006-2007) of instantaneous measurements of photosynthesis from either canopy towers or excised branches. In measurements on excised branches, photosynthetic nitrogen use efficiency (micromol CO2 s(-1) g(-1) N) was significantly decreased (-13%) by NO3(-) additions. Furthermore, we found no consistent NO3(-) effect across all sites in either current foliage or leaf litter collected annually throughout the study (1993-2007) and analyzed for delta 13C and delta 18O, isotopes that can be used together to integrate changes in photosynthesis over time. We observed a small but significant NO3(-) effect on the average area and mass of individual leaves from the excised branches, but these differences varied by site and were countered by changes in leaf number. These photosynthesis and leaf area data together suggest that NO3(-) additions have not stimulated photosynthesis. There is no evidence that nutrient deficiencies have developed at

  4. Haemodialysis is an effective treatment in acute metabolic decompensation of maple syrup urine disease

    Directory of Open Access Journals (Sweden)

    P.S. Atwal

    2015-09-01

    Full Text Available Acute metabolic decompensation in maple syrup urine disease can occur during intercurrent illness and is a medical emergency. A handful of reports in the medical literature describe the use of peritoneal dialysis and haemodialysis as therapeutic inventions. We report the only patient from our centre to have haemodialysis performed in this setting. Combined with dietary BCAA restriction and calorific support, haemodialysis allows rapid reduction in plasma leucine concentrations considerably faster than conservative methods.

  5. A Maple Package for the Painlevé Test of Nonlinear Partial Differential Equations

    Institute of Scientific and Technical Information of China (English)

    徐桂琼; 李志斌

    2003-01-01

    A Maple package, named PLtest, is presented to study whether or not nonlinear partial differential equations the standard WTC algorithm and the Kruskal simplification algorithm. Therefore, we not only study whether the given PDEs pass the test or not, but also obtain its truncated expansion form related to some integrability properties. Several well-known nonlinear models with physical interests illustrate the effectiveness of this package.

  6. Thirty-two years of change in an old-growth Ohio beech-maple forest.

    Science.gov (United States)

    Runkle, James R

    2013-05-01

    Old-growth forests dominated by understory-tolerant tree species are among forest types most likely to be in equilibrium. However, documentation of the degree to which they are in equilibrium over decades-long time periods is lacking. Changes in climate, pathogens, and land use all are likely to impact stand characteristics and species composition, even in these forests. Here, 32 years of vegetation changes in an old-growth beech (Fagus grandifolia)-sugar maple (Acer saccharum) forest in Hueston Woods, southwest Ohio, USA, are summarized. These changes involve canopy composition and structure, turnover in snags, and development of vegetation in treefall gaps. Stand basal area and canopy density have changed little in 32 years. However, beech has decreased in canopy importance (49% to 32%) while sugar maple has increased (32% to 47%). Annual mortality was about 1.3% throughout the study period. Mortality rates increased with stem size, but the fraction of larger stems increased due to ingrowth from smaller size classes. Beech was represented by more very large stems than small canopy stems: over time, death of those larger stems with inadequate replacement has caused the decrease in beech importance. Sugar maple was represented by more small canopy stems whose growth has increased its importance. The changes in beech and sugar maple relative importance are hypothesized to be due to forest fragmentation mostly from the early 1800s with some possible additional effects associated with the formation of the state park. Snag densities (12-16 snags/ha) and formation rates (1-3 snags.ha(-1).yr(-1)) remained consistent. The treefall gaps previously studied are closing, with a few, large stems remaining. Death of gap border trees occurs consistently enough to favor species able to combine growth in gaps and survival in the understory.

  7. Spatial coexistence of American beech and sugar maple regeneration in post-harvest northern hardwood forests

    OpenAIRE

    Nelson, Andrew S.; Wagner, Robert G.

    2014-01-01

    International audience; & Context Fine scale regeneration patterns of coexistent spe-cies are influenced by regeneration mechanisms and microsite requirements. Spatial patterns may be either disjunct or over-lapping, which will determine competitive effects and microsite dominance, and future forest composition. & Aims Using American beech (Fagus grandifolia Ehrh.) and sugar maple (Acer saccharum Marshall) as an example, three hypotheses were tested: (1) random beech spatial patterns, (2) clu...

  8. Using Maple + GRTensorII in teaching basics of General Relativity and Cosmology

    CERN Document Server

    Sporea, Ciprian A

    2014-01-01

    In this article we propose some Maple procedures, for teaching purposes, to study the basics of General Relativity (GR) and Cosmology. After presenting some features of GRTensorII, a package specially built to deal with GR, we give two examples of how one can use these procedures. In the first example we build the Schwarzschild solution of Einstein equations, while in the second one we study some simple cosmological models.

  9. Spatial and temporal variation of forest floor, throughfall, and stemflow properties associated with Bigleaf Maple in a mixed conifer forest of coastal British Columbia

    OpenAIRE

    Hamdan, Khaled Ahmad

    2012-01-01

    Bigleaf maple (Acer macrophyllum Pursh) is a large deciduous tree that is abundant in western North America. This study addressed whether the predicted increase in abundance of bigleaf maple because of climate change could influence forest hydrology and site fertility due to species-specific effects on incident rainfall distribution and nutrient cycling. The study examined the spatial and temporal variation of forest floor, throughfall, and stemflow properties associated with bigleaf maple in...

  10. Profundidade de semeadura e presença de palha afetam a emergência de plântulas de Vernonia ferruginea Sowing depth and presence of straw affect emergence of Vernonia ferruginea seedling

    Directory of Open Access Journals (Sweden)

    A.L. Alberguini

    2010-01-01

    Full Text Available A compreensão sobre a biologia de plantas daninhas pode contribuir significativamente no estabelecimento de estratégias adequadas para seu manejo, além de possibilitar o desenvolvimento de ferramentas de controle não químico. O objetivo deste trabalho foi estudar o efeito de profundidade de semeadura, tipo de solo, tipo e quantidade de palha na emergência de plântulas de Vernonia ferruginea (assa-peixe. No primeiro experimento, sementes da espécie foram colocadas em dois substratos (terra e areia e em sete profundidades (0; 0,0025; 0,005; 0,01; 0,02; 0,04; e 0,08 m. No segundo experimento, determinou-se o efeito de palha de cana-de-açúcar, capim-braquiária e milho em cinco quantidades (0,0; 1,5; 3,0; 6,0; e 9,0 t ha-1 na emergência de V. ferruginea. Maior emergência foi obtida na superfície e em 0,0025 m em ambos os substratos. A palha de milho foi a que mais inibiu a emergência de V. ferruginea, em todas as quantidades testadas.Basic information on the biology of weeds can contribute significantly to building appropriate strategies for their management, and developing non-chemical control tools. The aim of this work was to study the effect of sowing depth, soil type, and litter type and amount on the emergence of Vernonia ferruginea seedlings. In the first experiment, seeds of this species were placed in two substrates (soil and sand at seven depths (0, 0.0025, 0.005, 0.01, 0.02, 0.04 and 0.08 m. In the second experiment, the effect of sugarcane straw, signal grass and maize was determined in five amounts (0.0, 1.5, 3.0, 6.0 and 9.0 t ha-1 on the emergence of V. ferruginea. The highest emergence was observed on the surface and at 0.0025 m in both substrates. Corn straw inhibited emergence of V. ferruginea the most, in all the amounts tested.

  11. Insects Attracted to Maple Sap: Observations from Prince Edward Island, Canada

    Directory of Open Access Journals (Sweden)

    Christopher Majka

    2010-07-01

    Full Text Available The collection of maple sap for the production of maple syrup is a large commercial enterprise in Canada and the United States. In Canada, which produces 85% of the world’s supply, it has an annual value of over $168 million CAD. Over 38 million trees are tapped annually, 6.5% of which use traditional buckets for sap collection. These buckets attract significant numbers of insects. Despite this, there has been very little investigation of the scale of this phenomenon and the composition of insects that are attracted to this nutrient source. The present paper reports the results of a preliminary study conducted on Prince Edward Island, Canada. Twenty-eight species of Coleoptera, Lepidoptera, and Trichoptera were found in maple sap buckets, 19 of which are known to be attracted to saps and nectars. The physiological role of sap feeding is discussed with reference to moths of the tribe Xylenini, which are active throughout the winter, and are well documented as species that feed on sap flows. Additionally, 18 of the 28 species found in this study are newly recorded in Prince Edward Island.

  12. Morphological and molecular identification of phytophthora species from maple trees in Serbia

    Directory of Open Access Journals (Sweden)

    Milenković Ivan

    2014-01-01

    Full Text Available The paper presents the results of the study performed with aims to determine the presence and diversity of Phytophthora species on maple trees in Serbia. Due to high aggressiveness and their multicyclic nature, presence of these pathogens is posing significant threat to forestry and biodiversity. In total, 29 samples of water, soil and tissues were taken from 10 different localities, and six different maple hosts were tested. After the isolation tests, 17 samples from five different maple hosts were positive for the presence of Phytophthora spp., and 31 isolates were obtained. After the detailed morphological and physiological classification, four distinct groups of isolates were separated. DNA was extracted from selected representative isolates and molecular identification with sequencing of ITS region was performed. Used ITS4 and ITS6 primers successfully amplified the genomic DNA of chosen isolates and morphological identification of obtained isolates was confirmed after the sequencing. Four different Phytophthora species were detected, including P. cactorum, P. gonapodyides, P. plurivora and P. lacustris. The most common isolated species was homothallic, and with very variable and semipapillate sporangia, P. plurivora with 22 obtained isolates. This is the first report of P. plurivora and P. gonapodyides on A. campestre, P. plurivora and P. lacustris on Acer heldreichii and first report of P. lacustris on A. pseudoplatanus and A. tataricum in Serbia. [Projekat Ministarstva nauke Republike Srbije, br. TR 37008

  13. [Maple syrup urine disease of neonates: report of two cases and review of literature].

    Science.gov (United States)

    Chen, Zheng; Luo, Fang; Wu, Xiu-jing; Shi, Li-Ping

    2010-09-01

    To analyze and summarize clinical manifestation of maple syrup urine disease (MSUD) of neonates. Data of two cases with neonatal MSUD and the reports of 15 cases seen in the past 15 years in China were reviewed and analyzed. There was an increasing number of reports of cases with neonatal MSUD. All the 17 cases had the symptom of poor feeding between 3 h and 8 d after birth; 7 cases had family history; 14 cases showed progressive neurologic signs. Odor of maple syrup occurred in 8 cases. Blood levels of branched-chain amino acids (BCAA) significantly increased in 13 cases and 6 neonates were diagnosed using tandem mass spectrometry. Urinary levels of BCAA and metabolite elevated in 12 cases and 5 neonates were diagnosed using gas chromatography-mass spectrometry. MRI/CT demonstrated abnormal signal in 10 cases. Twelve cases died or their parents gave up treatment and one case had cerebral palsy; 4 cases were treated with BCAA-free formula milk and showed improved outcome. Newborns with MSUD often had early appeared non-specific symptoms with poor feeding and lethargy, most cases later showed an odor resembling maple syrup and neurologic signs. For patients who were suspected of having MSUD, blood and urine concentrations of BCAA should be tested for early diagnosis. Specific MRI edema signal from brain suggests the possibility of MSUD. Early intervention and treatment after diagnosis, with compliance of parents, would improve the patient's outcome.

  14. Building food safety into the company culture: a look at Maple Leaf Foods.

    Science.gov (United States)

    Lone, Jespersen; Huffman, Randy

    2014-07-01

    Maple Leaf Foods learned a hard lesson following its tragic 2008 Listeria outbreak that ended up taking the lives of 23 Canadians. The organization has since 2008 transformed its commitment to food safety with a strong drive and manifest in embedding sustainable food safety behaviours into the existing company culture. Its focus on combining technical risk analysis with behavioural sciences has led to the development and deployment of a food safety strategy deeply rooted in the company values and management commitment. Using five tactics described in this article the organization has been on a journey towards food safety transformation through adoption of best practices for people and systems. The approach to food safety has been one where food safety is treated as a non-competitive issue and Maple Leaf Foods have been open to sharing learning about what happened and how the organization will continue to take a leadership position in food safety to continuously raise the bar for food safety across the industry. Maple Leaf Foods has benefited tremendously by learning about best practice from numerous companies in North America and around the world. The authors believe this brief story will bring value to others as we continue to learn and improve.

  15. Sugar Maple Pigments Through the Fall and the Role of Anthocyanin as an Analytical Tool

    Science.gov (United States)

    Lindgren, E.; Rock, B.; Middleton, E.; Aber, J.

    2008-12-01

    Sugar maple habitat is projected to almost disappear in future climate scenarios. In fact, many institutions state that these trees are already in decline. Being able to detect sugar maple health could prove to be a useful analytical tool to monitor changes in phenology. Anthocyanin, a red pigment found in sugar maples, is thought to be a universal indicator of plant stress. It is very prominent in the spring during the first flush of leaves, as well as in the fall as leaves senesce. Determining an anthocyanin index that could be used with satellite systems will provide a greater understanding of tree phenology and the distribution of plant stress, both over large areas as well as changes over time. The utilization of anthocyanin for one of it's functions, prevention of oxidative stress, may fluctuate in response to changing climatic conditions that occur during senescence or vary from year to year. By monitoring changes in pigment levels and antioxidant capacity through the fall, one may be able to draw conclusions about the ability to detect anthocyanin remotely from space-based systems, and possibly determine a more specific function for anthocyanin during fall senescence. These results could then be applied to track changes in tree stress.

  16. New Gallotannin and other Phytochemicals from Sycamore Maple (Acer pseudoplatanus) Leaves.

    Science.gov (United States)

    Zhang, Lu; Tu, Zong-cai; Yuan, Tao; Ma, Hang; Niesen, Daniel B; Wang, Hui; Seeram, Navindra P

    2015-11-01

    The maple (Acer) genus is a reported source of bioactive (poly)phenols, including gallotannins, but several of its members, such as the sycamore maple (A. pseudoplatanus), remain uninvestigated. Herein, thirty-nine compounds, including a new gallotannin, 1,2,3-tri-O-galloyl-6-O-(p-hydroxybenzoyl)-β-D- glucopyranoside (1), and thirty-eight (2-39) known compounds, consisting of four gallotannins, one ellagitannin, thirteen flavonoids, eight hydroxycinnamic acids, ten benzoic acid derivatives, and two sesquiterpenoids, were isolated from sycamore maple leaves. Their structures were determined based on NMR and mass spectral analyses. The isolates were evaluated for α-glucosidase inhibitory and antioxidant activities. Among the isolates, the gallotannins were the most potent α-glucosidase inhibitors with thirteen-fold more potent activity compared with the clinical drug, acarbose (IC50 = 16-31 vs. 218 µM). Similarly, the gallotannins showed the highest antioxidant activities, followed by the other phenolic sub-classes, while the sesquiterpenoids were inactive.

  17. Proteome analysis of Norway maple (Acer platanoides L. seeds dormancy breaking and germination: influence of abscisic and gibberellic acids

    Directory of Open Access Journals (Sweden)

    Pawłowski Tomasz A

    2009-05-01

    Full Text Available Abstract Background Seed dormancy is controlled by the physiological or structural properties of a seed and the external conditions. It is induced as part of the genetic program of seed development and maturation. Seeds with deep physiological embryo dormancy can be stimulated to germinate by a variety of treatments including cold stratification. Hormonal imbalance between germination inhibitors (e.g. abscisic acid and growth promoters (e.g. gibberellins is the main cause of seed dormancy breaking. Differences in the status of hormones would affect expression of genes required for germination. Proteomics offers the opportunity to examine simultaneous changes and to classify temporal patterns of protein accumulation occurring during seed dormancy breaking and germination. Analysis of the functions of the identified proteins and the related metabolic pathways, in conjunction with the plant hormones implicated in seed dormancy breaking, would expand our knowledge about this process. Results A proteomic approach was used to analyse the mechanism of dormancy breaking in Norway maple seeds caused by cold stratification, and the participation of the abscisic (ABA and gibberellic (GA acids. Forty-four proteins showing significant changes were identified by mass spectrometry. Of these, eight spots were identified as water-responsive, 18 spots were ABA- and nine GA-responsive and nine spots were regulated by both hormones. The classification of proteins showed that most of the proteins associated with dormancy breaking in water were involved in protein destination. Most of the ABA- and GA-responsive proteins were involved in protein destination and energy metabolism. Conclusion In this study, ABA was found to mostly down-regulate proteins whereas GA up-regulated proteins abundance. Most of the changes were observed at the end of stratification in the germinated seeds. This is the most active period of dormancy breaking when seeds pass from the quiescent

  18. The effect of ectomycorrhizal fungi and bacteria on pine seedlings

    Directory of Open Access Journals (Sweden)

    Hanna Dahm

    2014-08-01

    Full Text Available The effect of ecomycorrhizal fungi (Hebelon crustuliniforme(Bull.: Fr. Quél. 5392 and Pisolithus tinctorius (Pers. Coker et Couch 5335 and bacteria (Bacillus polymyxa and Azospirillum brasilense. associated with mycorrhizas on the growth of pine seedligs was investigated. In addition the influence of bacteria on fungal biomass production and the relationship between ectomycorrhizal fungi and fungi pathogenic to root of pine seedlings were determined. In general, the shoot/root ratio was higher in plants inoculated with Hebeloma crustuliniforme and bacteria than in the control seedlings (grown only under sterile conditions. In non-sterile substrate the root/shoot ratio of the mycorrhizal seedlings was lower as compared to the control. Similar phenomenon was noted in plants inoculated with the mycorrhizal fungus Pisolithus tinetorius. The bacteria used as well as the time of introduction of these organisms into the cultures of mycorrhiza fungi affected the production of fungal biomass. Hebeloma crustuliniforme and Pisolithus tinctorius inhibited the growth of Rizoctonia solani and Fusarium oxysporum fungi pathogenic to pine seedlings.

  19. Photosynthetic efficiency of Pedunculate oak seedlings under simulated water stress

    Directory of Open Access Journals (Sweden)

    Popović Zorica

    2010-01-01

    Full Text Available Photosynthetic performance of seedlings of Quercus robur exposed to short-term water stress in the laboratory conditions was assessed through the method of induced fluorometry. The substrate for seedlings was clayey loam, with the dominant texture fraction made of silt, followed by clay and fine sand, with total porosity 68.2%. Seedlings were separated in two groups: control (C (soil water regime in pots was maintained at the level of field water capacity and treated (water-stressed, WS (soil water regime was maintained in the range of wilting point and lentocapillary capacity. The photosynthetic efficiency was 0.642±0.25 and 0.522±0.024 (WS and C, respectively, which was mostly due to transplantation disturbances and sporadic leaf chlorosis. During the experiment Fv/Fm decreased in both groups (0.551±0.0100 and 0.427±0.018 in C and WS, respectively. Our results showed significant differences between stressed and control group, in regard to both observed parameters (Fv/Fm and T½. Photosynthetic efficiency of pedunculate oak seedlings was significantly affected by short-term water stress, but to a lesser extent than by sufficient watering.

  20. Growth and Mineral Composition of Passion Fruit Seedlings

    Directory of Open Access Journals (Sweden)

    Edson Batista Lopes

    2010-06-01

    Full Text Available The aim of this study was to evaluate the growth and mineral composition of the yellow passion fruit plant seedlings (Passiflora edulis Sims f. flavicarpa Degener in fertilized substrates with boron and kalium, with and without coconut fiber (25 % e 0% and bovine manure (15%. The treatments were distributed in a outlined random block with four blocks and four seedlings per portion being five kalium doses and five boron doses combined according to the main Composite Central of Box. Each 20 days were done evaluations. Were analyzed the dry and green matter of the root and the leaf, foliated area and nutriment contents of the leaf. The results were submitted to analysis of change and regression. There was no significant effect of the treatments on the seedling's height, diameter of the shaft, number of leaves and foliated area. The coconut fiber doesn’t affect their growth and mineral composition. The kalium increased in a lineal way the root growth and aerial part of the seedlings, either the foliar contents of kalium, but reduce magnesium proportions. The boron increased the foliar contents of boron and reduced the nitrogen’s.

  1. Arborescent palm seed morphology and seedling distribution

    Directory of Open Access Journals (Sweden)

    Rodolfo Salm

    Full Text Available This study examines how the seed morphology of two large arborescent palms, Attalea maripa (Aubl. Mart. and Astrocaryum aculeatum G. Mey, may affect their seed shadow in a seasonally dry Amazonian forest. In addition to being smaller and produced in larger numbers than those of A. aculeatum, A. maripa seeds also presented a substantially lower amount of nutritional reserves available for the embryo. However, A. maripa seedlings were found in much higher numbers than those of A. aculeatum. The results suggest that, within the spatial scale considered, the seed rain of A. maripa is more restricted to the area surrounding around reproductive conspecifics than that of A. aculeatum. Furthermore, in comparison with those of A. aculeatum, the smaller seeds of A. maripa might be less attractive to scatterhoarding rodents (e.g. Dasyprocta aguti. The pattern observed emphasizes the importance of scatterhoarding rodents as dispersers of large-seeded plant species in Neotropical forests.

  2. Arborescent palm seed morphology and seedling distribution.

    Science.gov (United States)

    Salm, Rodolfo

    2005-11-01

    This study examines how the seed morphology of two large arborescent palms, Attalea maripa (Aubl.) Mart. and Astrocaryum aculeatum G. Mey, may affect their seed shadow in a seasonally dry Amazonian forest. In addition to being smaller and produced in larger numbers than those of A. aculeatum, A. maripa seeds also presented a substantially lower amount of nutritional reserves available for the embryo. However, A. maripa seedlings were found in much higher numbers than those of A. aculeatum. The results suggest that, within the spatial scale considered, the seed rain of A. maripa is more restricted to the area surrounding around reproductive conspecifics than that of A. aculeatum. Furthermore, in comparison with those of A. aculeatum, the smaller seeds of A. maripa might be less attractive to scatterhoarding rodents (e.g. Dasyprocta aguti). The pattern observed emphasizes the importance of scatterhoarding rodents as dispersers of large-seeded plant species in Neotropical forests.

  3. Substrate influences ecophysiological performance of tree seedlings.

    Science.gov (United States)

    Pröll, Gisela; Hietz, Peter; Delaney, Christina M; Katzensteiner, Klaus

    2016-01-01

    Unfavourable soil conditions frequently limit tree regeneration in mountain forests on calcareous bedrock. Rocky, shallow organic soils on dolomite pose a particular problem for tree regeneration due to commonly restricted water and nutrient supplies. Moreover, an often dense layer of understorey vegetation competes for the limited resources available. Hence, an array of interacting factors impairs tree seedlings' performance on dolomite, but there is little information on the ecophysiological mechanisms. We studied the effects of substrate, competing vegetation and foliar nutrient concentrations on the photosynthetic rate (A), stomatal conductance (gs) and leaf water potentials (ψ) of sycamore (Acer pseudoplatanus L.), beech (Fagus sylvatica L.), spruce [Picea abies (L.) Karst.] and larch (Larix decidua Mill.) under controlled (well-watered/drought-stressed) conditions and under prevailing field conditions. While A and gs of well-watered spruce in the pot experiment were reduced by the mineral substrate, the organic dolomite substrate with dense competing vegetation reduced gs and ψ of sycamore, spruce and larch under drought-stressed conditions in the field. For sycamore and spruce, A and gs were strongly correlated with foliar nitrogen (N) and potassium (K) concentrations in the pot experiment. In contrast, soil water primarily affected beech and larch. Finally, dense competing vegetation negatively affected A and gs of spruce and A of larch on dolomite. Our results highlight the critical role of N, K and water availability for tree seedlings in shallow soils on calcareous bedrock. On these sites, natural tree regeneration is at particular risk from episodic drought, a likely consequence of climate change.

  4. Nutrientes afetando as mudas de alecrim-pimenta (Lippia sidoides Cham. e seus artrópodes Nutrients affecting "alecrim-pimenta" (Lippia sidoides Cham. seedlings and their arthropods

    Directory of Open Access Journals (Sweden)

    F.W.S. Silva

    2009-01-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito da omissão de nutrientes nas mudas de Lippia sidoides Cham. (Verbenaceae e seu possível efeito sobre os seus artrópodes, sendo os tratamentos: 1 testemunha; 2 completo 1 adubado com N, P, K, S, B, Cu, e Zn + calagem (C1; 3 completo 2: C1 sem calagem + Ca e Mg como sulfato (C2; 4 C1 sem calagem; 5 C1 sem N; 6 C1 sem P; 7 C1 sem K; 8 C1 sem S; 9 C1 sem B; 10 C1 sem Cu; 11 C1 sem Zn; 12 C2 sem Ca e 13 C2 sem Mg. O delineamento foi inteiramente casualizado com quatro repetições. O Tetranychus sp. (Acari: Tetranychidae atacou mais os tratamentos 3, 6, 9 e 13 e os maiores danos nos tratamentos 6 e 13. A maior população de Aphis gossypii Glover (Homoptera: Aphididae foi encontrada nos tratamentos 5, 6, 7, 8, 11 e 13, colonizando preferencialmente o tratamento 4. O Phenacoccus sp. (Hemiptera: Pseudococcidae foi encontrado em maior número nos tratamentos 4 e 9 e Insignorthezia insignis (Browne (Hemiptera: Ortheziidae em 13. Foram mais notados adultos de Bemisa tabaci (Genn. (Hemiptera: Aleyrodidae nos tratamentos 5, 7, 8 e 13 e ninfas nos três últimos tratamentos. Em geral, os tratamentos 1, 5 e 10 são os menos atacados por artrópodes. Dirigir a pulverização, quando necessário, sempre para a face inferior da folha.The aim of this work was to evaluate nutrient omission effect on Lippia sidoides Cham. (Verbenacea seedlings, as well as its possible effect on their arthropods. Treatments were: 1 control; 2 complete 1: fertilized with N, P, K, S, B, Cu, and Zn + lime (C1; 3 complete 2: C1 without lime + Ca and Mg as sulphate (C2; 4 C1 without lime; 5 C1 without N; 6 C1 without P; 7 C1 without K; 8 C1 without S; 9 C1 without B; 10 C1 without Cu; 11 C1 without Zn; 12 C2 without Ca; and 13 C2 without Mg. The experimental design was completely randomized, with four replicates. Tetranychus sp. (Acari: Tetranychidae predominantly attacked treatments 3, 6, 9 and 13, and the greatest damages were detected

  5. Effect of electrostatic field on seed germination and seedling growth of Sorbus pohuashanesis

    Institute of Scientific and Technical Information of China (English)

    YANG Ling; SHEN Hai-long

    2011-01-01

    A study was conducted to determine the effects of electro static field (ESF) treatment on seed germination and seedling growth of Sorbus pohuashanesis. The experiments were arranged by uniform design computed by the Data Processing System (DPS), including three levels of seeds soaking time, four levels of ESF intensity and four levels of ESF treatment time, with 12 treatments. Ten seeds were used in each treatment with three replicates. Seed vigor, seed germinating ability,emergence rate of seedling, survival rate of seedling, and seedling height and diameter, as well as the change in activities of superoxide dismutase (SOD), soluble protein contents, total chlorophyll contents, soluble total sugar contents in leaves of S. pohuashanensis seedlings were measured after ESF treatments. The experiment results show that ESF treatment could improve the water absorption ability of dry seeds of S. pohuashanensis, resulting in fast germination at room temperature under light conditions. Combined treatment of ESF with cold stratification could increase seed germination percentage significantly (to 42.20%),promote seedling height growth, affect leaf SOD activity, and could raise contents of total chlorophyll, soluble protein, and total soluble sugar in leaves. Seed soaking time had a significant effect on seed relative electroconductivity, seed germination under light, SOD activity, soluble protein content and total soluble sugar content of seedling leaves. ESF intensity exerted a moderate effect on these indexes. ESF treatment time only had significant effect on total chlorophyll contents, no evident effect on other indexes.

  6. Mycorrhizae of Japanese black pine (Pinus thunbergii): Protection of seedlings from acid mist and effect of acid mist on mycorrhiza formation

    Energy Technology Data Exchange (ETDEWEB)

    Maehara, Noritoshi; Kikuchi, Junichi; Futai, Kazuyoshi

    1993-01-01

    To determine the effects of acid precipitation on Japanese black pine (Pinus thunbergii Parl.) with and without mycorrhizae (Pisolithus tinctorius (Pers.) Coker et Couch), 1-year-old seedlings were exposed to simulated acid rain mist, pH 3.0, for 10 min per day twice a week for 3 or 4 months. Simulated acid mist adversely affected the transpiration rate and lowered the extractable phosphorus content on seedlings, but seedlings with mycorrhizae were less affected by acid mist than were nonmycorrhizal seedlings. Simulated acid mist also retarded mycorrhiza formation. 41 refs., 7 figs.

  7. Indoleacetaldehyde in Cucumber Seedlings 1

    Science.gov (United States)

    Purves, William K.; Brown, Hugh M.

    1978-01-01

    The presence of indoleacetaldehyde in cucumber (Cucumis sativus L.) cotyledons was demonstrated by thin layer chromatographic RF values in three solvent systems, by the formation and hydrolysis of a bisulfite adduct, and by chemical reduction to indoleethanol and oxidation to indoleacetic acid. Bioassays indicated a minimum indoleacetaldehyde content in etiolated cotyledons of 0.7 μg per kg fresh weight. Tissue samples from all parts of both green and etiolated cucumber seedlings reduced exogenously supplied indoleacetaldehyde to indoleethanol. PMID:16660219

  8. BINERY TECHNOLOGY IN DIFFERENTIAL EQUATION AND COMPUTER SCIENCE STUDY AT THE UNIVERSITIES BASED ON MAPLE-ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    Vasyl Kushnir

    2015-10-01

    Full Text Available The problems of training basics of binary technology creation while teaching differential equations and information-communication technology (ICT based on the Maple-technology are researched. The relevance of the study is resulted from the basic contradiction between the latest opportunities of modern ICT, in particular Maple-technology and traditional methods of teaching mathematical disciplines, including differential equations. It is not enough only occasional applications of Maple-technology while conducting the lessons of mathematics. Maple-technology opportunities allow to teach such differential equations by means of ICT. Thus it is necessary to solve the problem of the organic connection of traditional methods for solving differential equations and possibilities of Maple-technology regarding to the solving the generalization of high level. These actions include the simplification of the expression, solution of algebraic equations and systems, determining of eigenvalues and eigenvectors of matrices, differentiation and integration of scalar functions, vector functions and matrix functions, multiplication of matrix and matrix-vectors, the finding of the inverse matrix, etc. Binary classes are designed to teach mathematics and Computer science at the same time. Therefore, the creation of binary training technology is rather complicated problem. First of all, the teacher needs to develop an algorithm for determining the method for solving differential equations or systems of differential equations. This algorithm must consist of activities that can be automated in Maple-technology. Such actions are of a technical nature and do not have meaning-forming actions of a method of solving problems. Then efforts and attention to the subjects of the teaching will be directed to a method of solving the problem, the establishment of an appropriate algorithm and program in Maple-technology. The creation and set-up of the program algorithm, is carried

  9. The Impact of Moss Species and Biomass on the Growth of Pinus sylvestris Tree Seedlings at Different Precipitation Frequencies

    Directory of Open Access Journals (Sweden)

    Babs M. Stuiver

    2014-08-01

    Full Text Available Boreal forests are characterized by an extensive moss layer, which may have both competitive and facilitative effects on forest regeneration. We conducted a greenhouse experiment to investigate how variation in moss species and biomass, in combination with precipitation frequency, affect Pinus sylvestris seedling growth. We found that moss species differed in their effects on seedling growth, and moss biomass had negative effects on seedlings, primarily when it reached maximal levels. When moss biomass was maximal, seedling biomass decreased, whereas height and above- relative to below-ground mass increased, due to competition for light. The effect that moss biomass had on seedling performance differed among the moss species. Hylocomium splendens and Polytrichum commune reduced seedling growth the most, likely because of their taller growth form. Seedlings were not adversely affected by Sphagnum girgensohnii and Pleurozium schreberi, possibly because they were not tall enough to compete for light and improved soil resource availability. Reduced precipitation frequency decreased the growth of all moss species, except P. commune, while it impaired the growth of seedlings only when they were grown with P. commune. Our findings suggest that changes in moss species and biomass, which can be altered by disturbance or climate change, can influence forest regeneration.

  10. Deficiência hídrica no solo e seu efeito sobre transpiração, crescimento e desenvolvimento de mudas de duas espécies de eucalipto Soil water defcit affecting transpiration, growth and development of seedlings of two eucalyptus species

    Directory of Open Access Journals (Sweden)

    Fabrina Bolzan Martins

    2008-06-01

    Full Text Available A água é fundamental no metabolismo das plantas e uma redução na sua disponibilidade no solo pode afetar o crescimento, o desenvolvimento e a produtividade das culturas. O objetivo deste trabalho foi quantificar a influência do déficit hídrico no solo sobre a transpiração e sobre alguns parâmetros de crescimento (altura de planta e diâmetro do caule e desenvolvimento (número de folhas acumuladas na haste principal, em mudas de Eucalyptus grandis (Hill ex Maiden e Eucalyptus saligna (Smith. Para realização deste estudo, foi instalado um experimento em casa de vegetação, no Departamento de Fitotecnia da Universidade Federal de Santa Maria (Santa Maria, RS, que consistiu em duas épocas de semeadura, sendo a primeira em 1/10/2005 (E1 e a segunda em 12/5/2006 (E2. A água disponível, representada pela fração de água transpirável no solo (FATS, e os demais parâmetros foram medidos diariamente durante o período de imposição da deficiência hídrica. O início do decréscimo da transpiração, indicativo do fechamento dos estômatos, ocorreu quando a FATS foi de 0,9 (E2 e 0,7 (E1, para E. grandis, e de 0,7, para E. saligna, em ambas as épocas, indicando que o fechamento estomático em resposta ao déficit hídrico no solo é mais rápido nessas espécies perenes do que em culturas agrícolas anuais. Os parâmetros de crescimento e desenvolvimento das mudas decresceram imediatamente após o início do déficit hídrico no solo, antes mesmo de ser a transpiração afetada pela redução da água no solo.Water is a critical component of plant metabolism, and a reduction in soil water availability may affect crop growth, development and yield. The objective of this study was to quantify the influence of soil water deficit on transpiration and on some growth (plant height and stem diameter and development (main stem leaf number parameters of Eucalyptus grandis (Hill ex Maiden and E. saligna (Smith seedlings. For this purpose, a

  11. Simulated changes in biogenic VOC emissions and ozone formation from habitat expansion of Acer Rubrum (red maple)

    Science.gov (United States)

    Drewniak, Beth A.; Snyder, Peter K.; Steiner, Allison L.; Twine, Tracy E.; Wuebbles, Donald J.

    2014-01-01

    A new vegetation trend is emerging in northeastern forests of the United States, characterized by an expansion of red maple at the expense of oak. This has changed emissions of biogenic volatile organic compounds (BVOCs), primarily isoprene and monoterpenes. Oaks strongly emit isoprene while red maple emits a negligible amount. This species shift may impact nearby urban centers because the interaction of isoprene with anthropogenic nitrogen oxides can lead to tropospheric ozone formation and monoterpenes can lead to the formation of particulate matter. In this study the Global Biosphere Emissions and Interactions System was used to estimate the spatial changes in BVOC emission fluxes resulting from a shift in forest composition between oak and maple. A 70% reduction in isoprene emissions occurred when oak was replaced with maple. Ozone simulations with a chemical box model at two rural and two urban sites showed modest reductions in ozone concentrations of up to 5-6 ppb resulting from a transition from oak to red maple, thus suggesting that the observed change in forest composition may benefit urban air quality. This study illustrates the importance of monitoring and representing changes in forest composition and the impacts to human health indirectly through changes in BVOCs.

  12. The role of nurse functional types in seedling recruitment dynamics of alternative states in rangelands

    Science.gov (United States)

    López, Dardo R.; Cavallero, Laura

    2017-02-01

    In arid ecosystems, recruitment dynamics are limited by harsh environmental conditions and greatly depend on the net outcome of the balance between facilitation and competition. This outcome can change as a consequence of degradation caused by livestock overgrazing. Also, distinct plant species may show a differential response to a common neighbour under the same environmental conditions. Therefore, ecosystem degradation could affect the net balance of plant-plant interactions, which can also depend on the functional traits of potential nurse species. The aim of this study is to assess the influence of alternative degradation states on (i) the density of seedlings of perennial species emerging in four microsite types, and on (ii) the relative interaction intensity (RII) between seedlings and potential nurses belonging to three functional types (deep- and shallow-rooted shrubs, and tussock grasses). During three years, we recorded seedling density of perennial species in four alternative degradation states in grass-shrubby steppes from northwestern Patagonia. The density of emerged seedlings of perennial species decreased sharply as degradation increased, showing non-linear responses in most microsites. Seedling density underneath deep-rooted shrubs was higher than underneath shallow-rooted shrubs and tussock grasses. Also, deep-rooted shrubs were the only functional type that recorded seedling emergence in highly degraded states. Deep-rooted shrubs had facilitative effects on the seedlings emerging and surviving underneath them, independently of ecosystem degradation. In contrast, RII between shallow-rooted shrubs and recently emerged seedlings, switched from positive effects in the less degraded states, to negative effects in the most degraded state. Tussock grasses recorded the weakest intensity of facilitative interactions with recently emerged seedlings, switching to competitive interactions as degradation increased. Our results suggest that species with key

  13. Root architecture and hydraulic conductance in nutrient deprived Pistacia lentiscus L. seedlings.

    Science.gov (United States)

    Trubat, Roman; Cortina, Jordi; Vilagrosa, Alberto

    2012-12-01

    Plants respond to low nutrient availability by modifying root morphology and root system topology. Root responses to nitrogen (N) and phosphorus (P) limitation may affect plant capacity to withstand water stress. But studies on the effect of nutrient availability on plant ability to uptake and transport water are scarce. In this study, we assess the effect of nitrogen and phosphorus limitation on root morphology and root system topology in Pistacia lentiscus L seedlings, a common Mediterranean shrub, and relate these changes to hydraulic conductivity of the whole root system. Nitrogen and phosphorus deprivation had no effect on root biomass, but root systems were more branched in nutrient limited seedlings. Total root length was higher in seedlings subjected to phosphorus deprivation. Root hydraulic conductance decreased in nutrient-deprived seedlings, and was related to the number of root junctions but not to other architectural traits. Our study shows that changes in nutrient availability affect seedling water use by modifying root architecture. Changes in nutrient availability should be taken into account when evaluating seedling response to drought.

  14. Toward an improved model of maple sap exudation: the location and role of osmotic barriers in sugar maple, butternut and white birch.

    Science.gov (United States)

    Cirelli, Damián; Jagels, Richard; Tyree, Melvin T

    2008-08-01

    Two theories have been proposed to explain how high positive pressures are developed in sugar maple stems when temperatures fluctuate around freezing. The Milburn-O'Malley theory proposes that pressure development is purely physical and does not require living cells or sucrose. The osmotic theory invokes the involvement of living cells and sucrose to generate an osmotic pressure difference between fibers and vessels, which are assumed to be separated by an osmotic barrier. We analyzed wood of Acer saccharum Marsh., Juglans cinerea L. and Betula papyrifera Marsh. (all generate positive pressures) examining three critical components of the osmotic model: pits in cell walls, selectivity of the osmotic barrier and stability of air bubbles under positive xylem pressure. We examined the distribution and type of pits directly by light and scanning electron microscopy (SEM), and indirectly by perfusion of branch segments with fluorescent dyes with molecular masses similar to sucrose. The latter approach allowed us to use osmotic surrogates for sucrose that could be tracked by epifluorescence. Infusion experiments were used to assess the compartmentalization of sucrose and to determine the behavior of gas bubbles as predicted by Fick's and Henry's laws. The SEM images of sugar maple revealed a lack of pitting between fibers and vessels but connections between fiber-tracheids and vessels were present. Fluorescein-perfusion experiments demonstrated that large molecules do not diffuse into libriform fibers but are confined within the domain of vessels, parenchyma and fiber-tracheids. Results of the infusion experiments were in agreement with those of the fluorescein perfusions and further indicated the necessity of a compartmentalized osmolyte to drive stem pressure, as well as the inability of air bubbles to maintain such pressure because of instability. These results support the osmotic model and demonstrate that the secondary cell wall is an effective osmotic barrier for

  15. Managing for delicious ecosystem service under climate change: can United States sugar maple (Acer saccharum) syrup production be maintained in a warming climate?

    Science.gov (United States)

    Stephen N. Matthews; Louis R. Iverson

    2017-01-01

    Sugar maple (Acer saccharum) is a highly valued tree in United States (US) and Canada, and its sap when collected from taps and concentrated, makes a delicious syrup. Understanding how this resource may be impacted by climate change and other threats is essential to continue management for maple syrup into the future. Here, we evaluate the current...

  16. Soil base saturation combines with beech bark disease to influence composition and structure of sugar maple-beech forests in an acid rain-impacted region

    Science.gov (United States)

    Gregory B. Lawrence; Todd C. McDonnell; Timothy J. Sullivan; Martin Dovciak; Scott W. Bailey; Michael R. Antidormi; Michael R. Zarfos

    2017-01-01

    Sugar maple, an abundant and highly valued tree species in eastern North America, has experienced decline from soil calcium (Ca) depletion by acidic deposition, while beech, which often coexists with sugar maple, has been afflicted with beech bark disease (BBD) over the same period. To investigate how variations in soil base saturation combine with effects of BBD in...

  17. Comparison of the enhancement of plasma glucose levels in type 2 diabetes Otsuka Long-Evans Tokushima Fatty rats by oral administration of sucrose or maple syrup.

    Science.gov (United States)

    Nagai, Noriaki; Ito, Yoshimasa; Taga, Atsushi

    2013-01-01

    Maple syrup is used as a premium natural sweeter, and is known for being good for human health. In the present study, we investigate whether maple syrup is suitable as a sweetener in the management of type 2 diabetes using Otsuka Long-Evans Tokushima Fatty (OLETF) rats, a model of type 2 diabetes mellitus. OLETF rats develop type 2 diabetes mellitus by 30 weeks of age, and 60-week-old OLETF rats show hyperglycemia and hypoinsulinemia via pancreatic β-cell dysfunction. The administration of sucrose or maple syrup following an OGT test increased plasma glucose (PG) levels in OLETF rats, but the enhancement in PG following the oral administration of maple syrup was lower than in the case of sucrose administration in both 30- and 60-week-old OLETF rats. Although, the insulin levels in 30-week-old OLETF rats also increased following the oral administration of sucrose or maple syrup, no increase in insulin levels was seen in 60-week-old OLETF rats following the oral administration of either sucrose or maple syrup. No significant differences were observed in insulin levels between sucrose- and maple syrup-administered OLETF rats at either 30 or 60 weeks of age. The present study strongly suggests that the maple syrup may have a lower glycemic index than sucrose, which may help in the prevention of type 2 diabetes.

  18. MAPLE deposition of polypyrrole-based composite layers for bone regeneration

    Energy Technology Data Exchange (ETDEWEB)

    Paun, Irina Alexandra, E-mail: irina.paun@physics.pub.ro [Faculty of Applied Sciences, University Politehnica of Bucharest, RO-060042 (Romania); National Institute for Laser, Plasma and Radiation Physics, Magurele, Bucharest RO-077125 (Romania); Acasandrei, Adriana Maria [Horia Hulubei National Institute for Physics and Nuclear Engineering IFIN-HH, Magurele, Bucharest RO-077125 (Romania); Luculescu, Catalin Romeo, E-mail: catalin.luculescu@inflpr.ro [National Institute for Laser, Plasma and Radiation Physics, Magurele, Bucharest RO-077125 (Romania); Mustaciosu, Cosmin Catalin [Horia Hulubei National Institute for Physics and Nuclear Engineering IFIN-HH, Magurele, Bucharest RO-077125 (Romania); Ion, Valentin [National Institute for Laser, Plasma and Radiation Physics, Magurele, Bucharest RO-077125 (Romania); Mihailescu, Mona; Vasile, Eugenia [Faculty of Applied Sciences, University Politehnica of Bucharest, RO-060042 (Romania); Dinescu, Maria, E-mail: dinescum@nipne.ro [National Institute for Laser, Plasma and Radiation Physics, Magurele, Bucharest RO-077125 (Romania)

    2015-12-01

    Highlights: • PPy-based composite layers for bone regeneration were produced by MAPLE. • Conductive PPy nanograins were embedded in insulating PLGA and PU matrices. • PLGA was chosen for providing biodegradability and PU for toughness and elasticity. • The layers conductivities reached 10{sup −2} S/cm for PPy loadings of 1:10 weight ratios. • The layers promoted osteoblast viability, proliferation and mineralization. - Abstract: We report on biocompatible, electrically conductive layers of polypyrrole (PPy)-based composites obtained by Matrix Assisted Pulsed Laser Evaporation (MAPLE) for envisioned bone regeneration. In order to preserve the conductivity of the PPy while overcoming its lack of biodegradability and low mechanical resilience, conductive PPy nanograins were embedded in two biocompatible, insulating polymeric matrices, i.e. poly(lactic-co-glycolic)acid (PLGA) and polyurethane (PU). PLGA offers the advantage of full biodegradability into non-toxic products, while PU provides toughness and elasticity. The PPy nanograins formed micro-domains and networks within the PLGA and PU matrices, in a compact spatial arrangement favorable for electrical percolation. The proposed approach allowed us to obtain PPy-based composite layers with biologically meaningful conductivities up to 10{sup −2} S/cm for PPy loadings as low as 1:10 weight ratios. Fluorescent staining and viability assays showed that the MG63 osteoblast-like cells cultured on the PPy-based layers deposited by MAPLE were viable and retained their capacity to proliferate. The performance of the proposed method was demonstrated by quantitative evaluation of the calcium phosphate deposits from the cultured cells, as indicative for cell mineralization. Electrical stimulation using 200 μA currents passing through the PPy-based layers, during a time interval of 4 h, enhanced the osteogenesis in the cultured cells. Despite their lowest conductivity, the PPy/PU layers showed the best

  19. Fungi in Ontario maple syrup & some factors that determine the presence of mold damage.

    Science.gov (United States)

    Frasz, Samantha L; Miller, J David

    2015-08-17

    Maple syrup is a high value artisanal product produced mainly in Canada and a number of States primarily in the northeast USA. Mold growth (Wallemia sebi) on commercial product was first reported in syrup in 1908. Since then, few data have been published. We conducted a systematic examination for fungi in maple syrup from 68 producers from all of the syrup-producing areas of Ontario, Canada. The mean pH of the samples was pH 6.82, sugar content averaged 68.0±0.89 °Brix and aw averaged 0.841±0.011. Some 23 species of fungi were isolated based on morphology and molecular techniques. The most common fungus in the maple syrup samples was Eurotium herbariorum, followed by Penicillium chrysogenum, Aspergillus penicillioides, Aspergillus restrictus, Aspergillus versicolor and two species of Wallemia. Cladosporium cladosporioides was also common but only recovered when fungi known from high sugar substrates were also present in the mold damaged sample. The rarely reported yeast Citeromyces matrinsis was found in samples from three producers. There appear to be three potential causes for mold damage observed. High aw was associated with about one third of the mold damage. Independently, cold packing (bottling at ~25 °C) was a risk factor. However, syrup of good quality and quite low aw values was contaminated. We hypothesize that sanitation in the bottling line and other aspects of the bottling process may be partial explanations. Clarifying this requires further study. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. [SADE] a Maple package for the symmetry analysis of differential equations

    Science.gov (United States)

    Rocha Filho, Tarcísio M.; Figueiredo, Annibal

    2011-02-01

    We present the package SADE (Symmetry Analysis of Differential Equations) for the determination of symmetries and related properties of systems of differential equations. The main methods implemented are: Lie, nonclassical, Lie-Bäcklund and potential symmetries, invariant solutions, first-integrals, Nöther theorem for both discrete and continuous systems, solution of ordinary differential equations, order and dimension reductions using Lie symmetries, classification of differential equations, Casimir invariants, and the quasi-polynomial formalism for ODE's (previously implemented by the authors in the package QPSI) for the determination of quasi-polynomial first-integrals, Lie symmetries and invariant surfaces. Examples of use of the package are given. Program summaryProgram title: SADE Catalogue identifier: AEHL_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEHL_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC license, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 27 704 No. of bytes in distributed program, including test data, etc.: 346 954 Distribution format: tar.gz Programming language: MAPLE 13 and MAPLE 14 Computer: PCs and workstations Operating system: UNIX/LINUX systems and WINDOWS Classification: 4.3 Nature of problem: Determination of analytical properties of systems of differential equations, including symmetry transformations, analytical solutions and conservation laws. Solution method: The package implements in MAPLE some algorithms (discussed in the text) for the study of systems of differential equations. Restrictions: Depends strongly on the system and on the algorithm required. Typical restrictions are related to the solution of a large over-determined system of linear or non-linear differential equations. Running time: Depends strongly on the order, the complexity of the differential

  1. Flexible heterostructures based on metal phthalocyanines thin films obtained by MAPLE

    Energy Technology Data Exchange (ETDEWEB)

    Socol, M., E-mail: cela@infim.ro [National Institute of Material Physics, 105 bis Atomistilor Street, PO Box MG-7, 077125 Bucharest-Magurele (Romania); Preda, N.; Rasoga, O. [National Institute of Material Physics, 105 bis Atomistilor Street, PO Box MG-7, 077125 Bucharest-Magurele (Romania); Breazu, C. [National Institute of Material Physics, 105 bis Atomistilor Street, PO Box MG-7, 077125 Bucharest-Magurele (Romania); University of Bucharest, Faculty of Physics, 405 Atomistilor Street, PO Box MG-11, 077125 Bucharest-Magurele (Romania); Stavarache, I. [National Institute of Material Physics, 105 bis Atomistilor Street, PO Box MG-7, 077125 Bucharest-Magurele (Romania); Stanculescu, F. [University of Bucharest, Faculty of Physics, 405 Atomistilor Street, PO Box MG-11, 077125 Bucharest-Magurele (Romania); Socol, G.; Gherendi, F.; Grumezescu, V.; Popescu-Pelin, G. [National Institute for Lasers, Plasma and Radiation Physics, 409 Atomistilor Street, PO Box MG-36, 077125 Bucharest-Magurele (Romania); Girtan, M. [Laboratoire de Photonique d’Angers, Université d’Angers, 2, Bd. Lavoisier, 49045 Angers (France); Stefan, N. [National Institute for Lasers, Plasma and Radiation Physics, 409 Atomistilor Street, PO Box MG-36, 077125 Bucharest-Magurele (Romania)

    2016-06-30

    Highlights: • Organic heterostructures prepared by MAPLE having a large absorbtion domain. • Photogeneration process is evidenced in the structure with ZnPc:TPyP mixed layer. • An increase in current value is observed in the structure with MgPc:TPyP mixed layer. - Abstract: Heterostructures based on zinc phthalocyanine (ZnPc), magnesium phthalocyanine (MgPc) and 5,10,15,20-tetra(4-pyrydil)21H,23H-porphine (TPyP) were deposited on ITO flexible substrates by Matrix Assisted Pulsed Laser Evaporation (MAPLE) technique. Organic heterostructures containing (TPyP/ZnPc(MgPc)) stacked or (ZnPc(MgPc):TPyP) mixed layers were characterized by X-ray diffraction-XRD, photoluminescence-PL, UV–vis and FTIR spectroscopy. No chemical decomposition of the initial materials was observed. The investigated structures present a large spectral absorption in the visible range making them suitable for organic photovoltaics applications (OPV). Scanning electron microscopy-SEM and atomic force microscopy-AFM revealed morphologies typical for the films prepared by MAPLE. The current–voltage characteristics of the investigated structures, measured in dark and under light, present an improvement in the current value (∼3 order of magnitude larger) for the structure based on the mixed layer (Al/MgPc:TPyP/ITO) in comparison with the stacked layer (Al/MgPc//TPyP/ITO). A photogeneration process was evidenced in the case of structures Al/ZnPc:TPyP/ITO with mixed layers.

  2. [Acute encephalopathy due to late-onset maple syrup urine disease in a school boy].

    Science.gov (United States)

    Qu, Su-Qing; Yang, Li-Cai; Luan, Zuo; Du, Kan; Yang, Hui

    2012-03-01

    Maple syrup urine disease is a common amino acids metabolic disease. In most patients, onset occurs in the neonatal period and infancy. In this study, the case of a school boy with acute encephalopathy due to late-onset maple syrup urine disease is summarized. The boy (8.5 years) was admitted because of acute encephalopathy after suffering from infection for two days at the age of eight and a half years. Metabolic acidosis, hyperuricemia and decreased protein level in cerebrospinal fluid were found by general laboratory tests. Magnetic resonance imaging of the brain revealed signal intensity abnormalities in the bilateral cerebellum dentate nucleus, brainstem, thalamus, putamen, caudate nucleus and cortex of the cerebral hemispheres. On T1WI and T2WI scanning, hyperintensive signal was found. Blood leucine and valine were significantly elevated. Urinary 2-hydroxy isovaleric acid, 3-hydroxybutyric acid, 2-keto isovaleric acid, and 2-keto acid also increased. Both the blood amino acid and urine organic acid profiles led to the diagnosis of maple syrup urine disease. In the acute period, the patient was treated with a large dose of vitamin B1, glucose, L-carnitine and a protein-restrict diet. The patient's condition improved significantly after five days of treatment, and he recovered completely two days later. Afterwards, treatment with vitamin B1, L-carnitine and a protein-restrict diet (1 g/kg/day) was continued. One and a half months later, blood amino acids and urine organic acids returned to normal. Magnetic resonance imaging of the brain also indicated a great improvement. It was concluded that inborn metabolic disease should be considered in the patients with an onset similar to acute encephalopathy. Early diagnosis and proper treatment can prevent brain damage and improve prognosis.

  3. Shelf Life Extension of Maple pea (Pisum sativum var. arvense L. Spread Using Sous Vide

    Directory of Open Access Journals (Sweden)

    Ķirse Asnate

    2016-12-01

    Full Text Available The aim of this study was to determine the effect of sous vide packaging on the shelf life of maple pea (Pisum sativum var. arvense L. spread. Pea spreads were made of ground re-hydrated cooked maple peas ‘Bruno’ (Pisum sativum var. arvense L., to which salt, citric acid, oil, and spices were added. Pea spread was stored in polyamide/polyethylene (PA/PE film pouches, packaged in vacuum and hermetically sealed. Pea spread pouches were heat treated in a water bath, then rapidly cooled in ice-water and stored at 4.0 ± 0.5 °C. Sous vide was applied in three different heat regimens +(65.0; 80.0 and 100.0 ± 0.5 °C with cooking times 5, 10, 15, 20, 25, and 30 min at a constant temperature. Total plate count was determined according to ISO 4833-1:2014 on Plate Count Agar and Enterobacteriaceae determination was performed in accordance with ISO 21528-2:2004 on Violet Red Bile Glucose Agar. Total plate count in pea spread without thermal treatment was 3.41 log10 CFU g−1, in all sous vide packaged pea spread samples microbial contamination was significantly lower (p < 0.05. Enterobacteriaceae were not detected in any samples. It is possible to extend the shelf life of sous vide maple pea spread up to 14 weeks when stored at 4.0 ± 0.5 °C.

  4. Microbial colonization of biopolymeric thin films containing natural compounds and antibiotics fabricated by MAPLE

    Energy Technology Data Exchange (ETDEWEB)

    Cristescu, R., E-mail: rodica.cristescu@inflpr.ro [National Institute for Lasers, Plasma and Radiation Physics, Lasers Department, PO Box MG-36, Bucharest-Magurele (Romania); Surdu, A.V.; Grumezescu, A.M.; Oprea, A.E.; Trusca, R.; Vasile, O. [Faculty of Applied Chemistry and Materials Science, Department of Science and Engineering of Oxide Materials and Nanomaterials, Politehnica University of Bucharest, Polizu Street No. 1–7, 011061 Bucharest (Romania); Dorcioman, G.; Visan, A.; Socol, G.; Mihailescu, I.N. [National Institute for Lasers, Plasma and Radiation Physics, Lasers Department, PO Box MG-36, Bucharest-Magurele (Romania); Mihaiescu, D. [Faculty of Applied Chemistry and Materials Science, Department of Organic Chemistry, Politehnica University of Bucharest, 1–7 Polizu Street, 011061 Bucharest (Romania); Enculescu, M. [National Institute of Materials Physics, PO Box MG-7, Bucharest-Magurele (Romania); Chifiriuc, M.C. [Microbiology Immunology Department, Faculty of Biology, Research Institute of the University of Bucharest—ICUB, Research Institute of the University of Bucharest, 77206 Bucharest (Romania); Boehm, R.D.; Narayan, R.J. [Biomedical Engineering, University of North Carolina, Chapel Hill, NC (United States); Chrisey, D.B. [Department of Physics and Engineering Physics, Tulane University, New Orleans, LA (United States)

    2015-05-01

    Highlights: • We deposited thin composite quercetin/polyvinylpyrrolidone/antibiotic films with close resemblance to the starting/drop-cast composition by MAPLE. • Quercetin flavonoid shows an anti-biofilm activity comparable to that of the tested large-spectrum antibiotics (norfloxacin or cefuroxime), especially in case of 72 h biofilms. • These results could account for the possible use of quercetin as an alternative to antibiotics to combat the mature biofilms developed on different substrates. • MAPLE may be used to produce implantable medical devices that provide a relatively long term in vitro stability and resistance to the growth of microorganisms. - Abstract: Although a great number of antibiotics are currently available, they are often rendered ineffective by the ability of microbial strains to develop genetic resistance and to grow in biofilms. Since many antimicrobial agents poorly penetrate biofilms, biofilm-associated infections often require high concentrations of antimicrobial agents for effective treatment. Among the various strategies that may be used to inhibit microbial biofilms, one strategy that has generated significant interest involves the use of bioactive surfaces that are resistant to microbial colonization. In this respect, we used matrix assisted pulsed laser evaporation (MAPLE) involving a pulsed KrF* excimer laser source (λ = 248 nm, τ = 25 ns, ν = 10 Hz) to obtain thin composite biopolymeric films containing natural (flavonoid) or synthetic (antibiotic) compounds as bioactive substances. Chemical composition and film structures were investigated by Fourier transform infrared spectroscopy and X-ray diffraction. Films morphology was studied by scanning electron microscopy and transmission electron microscopy. The antimicrobial assay of the microbial biofilms formed on these films was assessed by the viable cell counts method. The flavonoid-containing thin films showed increased resistance to microbial colonization

  5. Analysis of plastic residues in maple sap and syrup collected from tubing systems sanitized with isopropyl alcohol

    Directory of Open Access Journals (Sweden)

    Luc Lagacé

    2017-05-01

    Full Text Available A plastic tubing system operated under vacuum is usually used to collect sap from maple trees during spring time to produce maple syrup. This system is commonly sanitized with isopropyl alcohol (IPA to remove microbial contamination colonizing the system during the sugar season. Questions have been raised whether IPA would contribute to the leaching of plastic residues in maple sap and syrup coming from sanitized systems. First, an extraction experiment was performed in the lab on commercial plastic tubing materials that were submitted to IPA under harsh conditions. The results of the GC-MS analysis revealed the presence of many compounds that served has target for further tests. Secondly, tests were done on early and mid-season maple sap and syrup coming from many sugarbushes using IPA or not to determine potential concentrations of plastic residues. Results obtained from sap and syrup samples showed that no quantifiable (< 1–75 μg/L concentration of any plastic molecules tested was determined in all samples coming from IPA treated or not treated systems. However, some samples of first sap run used as a rinse solution to be discarded before the season start and that were coming from non sanitized or IPA sanitized systems, showed quantifiable concentrations of chemical residue such as ultraviolet protector (octabenzone. These results show that IPA can be safely used to sanitize maple sap collection system in regards to the leaching of plastic residues in maple sap and syrup and reinforced the need to thoroughly rinse the tubing system at the beginning of the season for both sanitized and non sanitized systems.

  6. Potts Model on Maple Leaf Lattice with Pure Three-Site Interaction

    Institute of Scientific and Technical Information of China (English)

    WANG Zhou-Fei; CHEN Li

    2005-01-01

    We use Monte Carlo method to study three-state Potts model on maple leaf lattice with pure three-site interaction. The critical behavior of both ferromagnetic and antiferromagnetic cases is studied. Our results confirm that the critical behavior of the ferromagnetic model is independent of the lattice details and lies in the universality class of the three-state ferromagnetic Potts model. For the antiferromagnetic case the transition is of the first order. We have calculated the energy jump and critical temperature in this area. We find there is a tricritical point separating the first order and second order phases for this system.

  7. O uso do software maple no ensino do cálculo diferencial e integral

    OpenAIRE

    Kaiber, Carmen; Pacheco, Sandra

    2006-01-01

    Este artigo apresenta resultados parciais do projeto de pesquisa “Investigando o potencial de utilização do software Maple no ensino do Cálculo Diferencial e Integral” que objetiva investigar possibilidades de utilização do referido software no desenvolvimento teórico e prático do Cálculo Diferencial e Integral. Metodologicamente, o projeto fundamenta-se nos princípios da Engenharia Didática que, segundo Artigue (1995), se caracteriza por ser um esquema experimental baseado nas realizações di...

  8. Gravity, torsion, Dirac field and computer algebra using MAPLE and REDUCE

    CERN Document Server

    Vulcanov, D N

    2002-01-01

    The article presents computer algebra procedures and routines applied to the study of the Dirac field on curved spacetimes. The main part of the procedures is devoted to the construction of Pauli and Dirac matrices algebra on an anholonomic orthonormal reference frame. Then these procedures are used to compute the Dirac equation on curved spacetimes in a sequence of special dedicated routines. A comparative review of such procedures obtained for two computer algebra platforms (REDUCE + EXCALC and MAPLE + GRTensorII) is carried out. Applications for the calculus of Dirac equation on specific examples of spacetimes with or without torsion are pointed out.

  9. Calculation of the Dirac equation in curved spacetimes with possible torsion using MAPLE and REDUCE

    Science.gov (United States)

    Vulcanov, Dumitru N.

    2003-08-01

    The article presents computer algebra procedures and routines applied to the study of the Dirac field on curved spacetimes. The main part of the procedures is devoted to the construction of Pauli and Dirac matrices algebra on an anholonomic orthonormal reference frame. Then these procedures are used to compute the Dirac equation on curved spacetimes in a sequence of special dedicated routines. A comparative review of such procedures obtained for two computer algebra platforms (REDUCE+EXCALC and MAPLE+GRTensorII) is carried out. Applications for the calculus of Dirac equation on specific examples of spacetimes with or without torsion are pointed out.

  10. Multiple Representations for Systems of Linear Equations Via the Computer Algebra System Maple

    Directory of Open Access Journals (Sweden)

    Dann G. Mallet

    2007-02-01

    Full Text Available A number of different representational methods exist for presenting the theory of linear equations and associated solution spaces. Discussed in this paper are the findings of a case study where first year undergraduate students were exposed to a new (to the department method of teaching linear systems which used visual, algebraic and data-based representations constructed using the computer algebra system Maple. Positive and negative impacts on the students are discussed as they apply to representational translation and perceived learning.

  11. Deposition of matrix-free fullerene films with improved morphology by matrix-assisted pulsed laser evaporation (MAPLE)

    DEFF Research Database (Denmark)

    Canulescu, Stela; Schou, Jørgen; Fæster, Søren;

    2013-01-01

    Thin films of C60 were deposited by matrix-assisted pulsed laser evaporation (MAPLE) from a frozen target of anisole with 0.67 wt% C60. Above a fluence of 1.5 J/cm2 the C60 films are strongly non-uniform and are resulting from transfer of matrix-droplets containing fullerenes. At low fluence...... the fullerene molecules in the films are intact, the surface morphology is substantially improved and there are no measurable traces of the matrix molecules in the film. This may indicate a regime of dominant evaporation at low fluence which merges into the MAPLE regime of liquid ejection of the host matrix...

  12. Diversity of seedling responses to drought

    NARCIS (Netherlands)

    Slot, M.; Poorter, L.

    2007-01-01

    Drought is an important seedling mortality agent in dry and moist tropical forests, and more severe and frequent droughts are predicted in the future. The effect of drought on leaf gas exchange and seedling survival was tested in a dry-down experiment with four tree species from dry and moist forest

  13. Calcium supplementation improves Na+/K+ ratio, antioxidant defense and glyoxalase systems in salt-stressed rice seedlings

    Directory of Open Access Journals (Sweden)

    Anisur eRahman

    2016-05-01

    Full Text Available The present study investigates the regulatory role of exogenous calcium (Ca in developing salt stress tolerance in rice seedlings. Hydroponically grown 13-d-old rice (Oryza sativa L. cv. BRRI dhan47 seedlings were exposed to 200 mM NaCl alone and combined with 2 mM CaCl2 and 2 mM ethylene glycol tetraacetic acid (EGTA, a Ca scavenger for three days. The salt stress caused growth inhibition, chlorosis and water shortage in the rice seedlings. The salt-induced stress disrupted ion homeostasis through Na+ influx and K+ efflux, and decreased other mineral nutrient uptake. Salt-induced stress caused oxidative stress in rice seedlings through lipid peroxidation, loss of plasma membrane integrity, higher reactive oxygen species (ROS production and methylglyoxal (MG formation. The salt-stressed rice seedlings supplemented with exogenous Ca recovered from water loss, chlorosis and growth inhibition. Calcium supplementation in the salt-stressed rice seedlings improved ion homeostasis by inhibition of Na+ influx and K+ leakage. Exogenous Ca also improved ROS and MG detoxification by improving the antioxidant defense and glyoxalase systems, respectively. On the other hand, applying EGTA along with salt and Ca again negatively affected the rice seedlings as EGTA negated Ca activity. It confirms that, the positive responses in salt-stressed rice seedlings to exogenous Ca were for Ca mediated improvement of ion homeostasis, antioxidant defense and glyoxalase system.

  14. Calcium Supplementation Improves Na+/K+ Ratio, Antioxidant Defense and Glyoxalase Systems in Salt-Stressed Rice Seedlings

    Science.gov (United States)

    Rahman, Anisur; Nahar, Kamrun; Hasanuzzaman, Mirza; Fujita, Masayuki

    2016-01-01

    The present study investigates the regulatory role of exogenous calcium (Ca) in developing salt stress tolerance in rice seedlings. Hydroponically grown 13-day-old rice (Oryza sativa L. cv. BRRI dhan47) seedlings were exposed to 200 mM NaCl alone and combined with 2 mM CaCl2 and 2 mM ethylene glycol tetraacetic acid (EGTA, a Ca scavenger) for 3 days. The salt stress caused growth inhibition, chlorosis and water shortage in the rice seedlings. The salt-induced stress disrupted ion homeostasis through Na+ influx and K+ efflux, and decreased other mineral nutrient uptake. Salt stress caused oxidative stress in seedlings through lipid peroxidation, loss of plasma membrane integrity, higher reactive oxygen species (ROS) production and methylglyoxal (MG) formation. The salt-stressed seedlings supplemented with exogenous Ca recovered from water loss, chlorosis and growth inhibition. Calcium supplementation in the salt-stressed rice seedlings improved ion homeostasis by inhibition of Na+ influx and K+ leakage. Exogenous Ca also improved ROS and MG detoxification by improving the antioxidant defense and glyoxalase systems, respectively. On the other hand, applying EGTA along with salt and Ca again negatively affected the seedlings as EGTA negated Ca activity. It confirms that, the positive responses in salt-stressed rice seedlings to exogenous Ca were for Ca mediated improvement of ion homeostasis, antioxidant defense and glyoxalase system. PMID:27242816

  15. Seed Size, the Only Factor Positively Affecting Direct Seeding Success in an Abandoned Field in Quebec, Canada

    Directory of Open Access Journals (Sweden)

    Annick St-Denis

    2013-06-01

    Full Text Available Direct tree seeding is potentially an economical technique for restoring forests on abandoned fields. However, the success of tree establishment depends on many factors related to species and seed characteristics, environmental conditions, competition and predation. We compared seedling emergence, survival and growth of six tree species of different seed sizes in a forest restoration project of abandoned fields. Species were seeded in plots with and without herbaceous vegetation and with and without protection from bird and mammal predation. Yellow birch (Betula alleghaniensis did not emerge in all treatments, paper birch (Betula papyrifera and tamarack (Larix laricina had a seedling emergence rate lower than 1%, and sugar maple (Acer saccharum had a low overall emergence rate of 6%. Seedling emergence reached 57% for northern red oak (Quercus rubra and 34% for red pine (Pinus resinosa, but survival of oak after one year was much higher (92% than pine seedlings (16%. Overall, protection from birds and mammals and elimination of the herbaceous vegetation cover had no detectable effects on seedling emergence, survival and height. Nonetheless, red oak seedlings growing in the presence of vegetation had a smaller diameter and shoot biomass and a larger specific leaf area. We conclude that only large seeded species, such as oak, should be used for forest restoration of abandoned fields by direct seeding in our region.

  16. 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.

  17. Production and development of eucalyptus seedlings in function of doses of phosphorus

    Directory of Open Access Journals (Sweden)

    José Henrique Tertulino Rocha

    2013-12-01

    Full Text Available This study evaluated the effect of phosphorus (P on the survival in the nursery and early development in the field of clonal Eucalyptus urophylla x Eucalyptus grandis seedlings. The experimental design was completely randomized with four treatments and five replicates of 30 plants per replicate. At the end of the cycle (90 days, 15 seedlings were used for determining the dry matter accumulation and nutrient concentration in the shoot. The rest was planted in the field to determine the percentage of survival and early development. The treatments consisted of four doses of P fertilization (0.0, 1.3, 2.6 and 5.2 mg plant-1. To obtain high quality seedlings in conditions similar to this experiment it is required doses of P in the range from 3.6 to 3.8 mg plant-1. Doses greater than 4 mg plant-1 affect the development and quality of eucalyptus seedlings. An adequate phosphorus fertilization of eucalyptus seedlings increase, by about 30%, the percentage of surviving seedlings in the field.

  18. Spring leaf phenology and the diurnal temperature range in a temperate maple forest

    Science.gov (United States)

    Hanes, Jonathan M.

    2014-03-01

    Spring leaf phenology in temperate climates is intricately related to numerous aspects of the lower atmosphere [e.g., surface energy balance, carbon flux, humidity, the diurnal temperature range (DTR)]. To further develop and improve the accuracy of ecosystem and climate models, additional investigations of the specific nature of the relationships between spring leaf phenology and various ecosystem and climate processes are required in different environments. This study used visual observations of maple leaf phenology, below-canopy light intensities, and micrometeorological data collected during the spring seasons of 2008, 2009, and 2010 to examine the potential influence of leaf phenology on a seasonal transition in the trend of the DTR. The timing of a reversal in the DTR trend occurred near the time when the leaves were unfolding and expanding. The results suggest that the spring decline in the DTR can be attributed primarily to the effect of canopy closure on daily maximum temperature. These findings improve our understanding of the relationship between leaf phenology and the diurnal temperature range in temperate maple forests during the spring. They also demonstrate the necessity of incorporating accurate phenological data into ecosystem and climate models and warrant a careful examination of the extent to which canopy phenology is currently incorporated into existing models.

  19. Spring leaf phenology and the diurnal temperature range in a temperate maple forest.

    Science.gov (United States)

    Hanes, Jonathan M

    2014-03-01

    Spring leaf phenology in temperate climates is intricately related to numerous aspects of the lower atmosphere [e.g., surface energy balance, carbon flux, humidity, the diurnal temperature range (DTR)]. To further develop and improve the accuracy of ecosystem and climate models, additional investigations of the specific nature of the relationships between spring leaf phenology and various ecosystem and climate processes are required in different environments. This study used visual observations of maple leaf phenology, below-canopy light intensities, and micrometeorological data collected during the spring seasons of 2008, 2009, and 2010 to examine the potential influence of leaf phenology on a seasonal transition in the trend of the DTR. The timing of a reversal in the DTR trend occurred near the time when the leaves were unfolding and expanding. The results suggest that the spring decline in the DTR can be attributed primarily to the effect of canopy closure on daily maximum temperature. These findings improve our understanding of the relationship between leaf phenology and the diurnal temperature range in temperate maple forests during the spring. They also demonstrate the necessity of incorporating accurate phenological data into ecosystem and climate models and warrant a careful examination of the extent to which canopy phenology is currently incorporated into existing models.

  20. Lipase immobilization for catalytic applications obtained using fumed silica deposited with MAPLE technique

    Science.gov (United States)

    Bloisi, Francesco; Califano, Valeria; Perretta, Giuseppe; Nasti, Libera; Aronne, Antonio; Di Girolamo, Rocco; Auriemma, Finizia; De Rosa, Claudio; Vicari, Luciano R. M.

    2016-06-01

    Lipases are enzymes used for catalyzing reactions of acylglycerides in biodiesel production from lipids, where enzyme immobilization on a substrate is required. Silica nanoparticles in different morphologies and configurations are currently used in conjunction with biological molecules for drug delivery and catalysis applications, but up to date their use for triglycerides has been limited by the large size of long-chain lipid molecules. Matrix assisted pulsed laser evaporation (MAPLE), a laser deposition technique using a frozen solution/suspension as a target, is widely used for deposition of biomaterials and other delicate molecules. We have carried out a MAPLE deposition starting from a frozen mixture containing fumed silica and lipase in water. Deposition parameters were chosen in order to increase surface roughness and to promote the formation of complex structures. Both the target (a frozen thickened mixture of nanoparticles/catalyst in water) and the deposition configuration (a small target to substrate distance) are unusual and have been adopted in order to increase surface contact of catalyst and to facilitate access to long-chain molecules. The resulting innovative film morphology (fumed silica/lipase cluster level aggregation) and the lipase functionality (for catalytic biodiesel production) have been studied by FESEM, FTIR and transesterification tests.

  1. Flexible heterostructures based on metal phthalocyanines thin films obtained by MAPLE

    Science.gov (United States)

    Socol, M.; Preda, N.; Rasoga, O.; Breazu, C.; Stavarache, I.; Stanculescu, F.; Socol, G.; Gherendi, F.; Grumezescu, V.; Popescu-Pelin, G.; Girtan, M.; Stefan, N.

    2016-06-01

    Heterostructures based on zinc phthalocyanine (ZnPc), magnesium phthalocyanine (MgPc) and 5,10,15,20-tetra(4-pyrydil)21H,23H-porphine (TPyP) were deposited on ITO flexible substrates by Matrix Assisted Pulsed Laser Evaporation (MAPLE) technique. Organic heterostructures containing (TPyP/ZnPc(MgPc)) stacked or (ZnPc(MgPc):TPyP) mixed layers were characterized by X-ray diffraction-XRD, photoluminescence-PL, UV-vis and FTIR spectroscopy. No chemical decomposition of the initial materials was observed. The investigated structures present a large spectral absorption in the visible range making them suitable for organic photovoltaics applications (OPV). Scanning electron microscopy-SEM and atomic force microscopy-AFM revealed morphologies typical for the films prepared by MAPLE. The current-voltage characteristics of the investigated structures, measured in dark and under light, present an improvement in the current value (∼3 order of magnitude larger) for the structure based on the mixed layer (Al/MgPc:TPyP/ITO) in comparison with the stacked layer (Al/MgPc//TPyP/ITO). A photogeneration process was evidenced in the case of structures Al/ZnPc:TPyP/ITO with mixed layers.

  2. Variation and correlation of properties in different grades of maple syrup.

    Science.gov (United States)

    Singh, Amritpal S; Jones, A Maxwell P; Saxena, Praveen K

    2014-03-01

    Thirty five commercial maple syrups from twelve producers in Southern Ontario were evaluated for properties including light transmittance, autofluorescence, density, pH, total soluble solids (TSS), glucose and fructose content, total phenol content, antioxidant potential and mineral content (Mg, Mn, P, Zn, Ca, K, Fe and Pb). A high degree of variability was found in many characteristics, often exceeding an order of magnitude. Syrups were categorized based on light transmission at 560 nm into amber (12), dark (13) and very dark (10) using International Maple Syrup Institute (IMSI) guidelines. No statistical differences were found among grades of syrup for density, pH, TSS, glucose, fructose, total reducing sugars, glucose:fructose ratio, magnesium, manganese or potassium. Darker syrups showed significantly higher autofluorescence, total phenol content, antioxidant potential, phosphorous, calcium and total mineral content. Significant negative correlations of percent transmission with total phenol content, antioxidant potential and total mineral content are reported. Significant positive correlations among total phenol content, antioxidant potential and total mineral content are also described. The results from this study suggest that darker syrups tend to contain more beneficial traits and may be applied in developing functional foods and value added products.

  3. MAPLE-based method to obtain biodegradable hybrid polymeric thin films with embedded antitumoral agents.

    Science.gov (United States)

    Dinca, Valentina; Florian, Paula E; Sima, Livia E; Rusen, Laurentiu; Constantinescu, Catalin; Evans, Robert W; Dinescu, Maria; Roseanu, Anca

    2014-02-01

    In this work, antitumor compounds, lactoferrin [recombinant iron-free (Apo-rLf)], cisplatin (Cis) or their combination were embedded within a biodegradable polycaprolactone (PCL) polymer thin film, by a modified approach of a laser-based technique, matrix-assisted pulsed laser evaporation (MAPLE). The structural and morphological properties of the deposited hybrid films were analyzed by Fourier-transform infrared spectroscopy (FTIR) and atomic force microscopy (AFM). The in vitro effect on the cells' morphology and proliferation of murine melanoma B16-F10 cells was investigated and correlated with the films' surface chemistry and topography. Biological assays revealed decreased viability and proliferation, lower adherence, and morphological modifications in the case of melanoma cells cultured on both Apo-rLf and Cis thin films. The antitumor effect was enhanced by deposition of Apo-rLf with Cis within the same film. The unique capability of the new approach, based on MAPLE, to embed antitumor active factors within a biodegradable matrix for obtaining novel biodegradable hybrid platform with increased antitumor efficiency has been demonstrated.

  4. m-DOPA addition in MAPLE immobilization of lipase for biosensor applications

    Directory of Open Access Journals (Sweden)

    Valeria Califano

    2015-12-01

    Full Text Available Matrix Assisted Pulsed Laser Evaporation (MAPLE is a thin film deposition technique which uses a pulsed laser beam impinging, inside a high vacuum chamber, on a frozen target containing the guest molecules in a volatile matrix to induce fast “evaporation” of the matrix, and ejection of the guest molecules. Lipase, an enzyme acting as a catalyst in hydrolysis of lipids, is widely used in biosensors for detection of triglycerides in blood serum. A key action to this purpose is lipase immobilization on a substrate. In a recent paper, we have shown that MAPLE technique is able to deposit lipase on a substrate in an active form. Here we show that addition to the guest/matrix target of a small amount of m-DOPA (3-(3,4-dihydroxyphenyl-2-methyl-l-alanine in order to improve adhesion and protect lipase secondary structure, also allows the lowering the laser pulse energy required for matrix evaporation and therefore the risk of damaging the enzyme.

  5. Interactions between organic matter and mineral surfaces along an earthworm invasion gradient in a sugar maple forest of Minnesota

    Science.gov (United States)

    Lyttle, A.; Yoo, K.; Aufdenkampe, A. K.; Sebestyen, S. D.; Hale, C.

    2012-12-01

    Sorption of organic matter on mineral surface is critical for protection of organic carbon (C) against decomposition and thus may potentially increase the capacity of soils to store C. Such sorption, however, requires physical contacts between organic matter and available mineral surfaces. This study attempts to better understand how bioturbation by invasive earthworms influences the contacts between organic matter and mineral surface, and affects sorption of organic matter on mineral surface. Vertical soil mixing is a direct consequence of the introduction of invasive earthworms in natural forests previously devoid of native earthworm populations. Here we focus on an intensively studied earthworm invasion chronosequence in a glaciated sugar maple forest in northern Minnesota. With the advance of invasive earthworms, leaf litter disappears while the A horizon expands at the expense of the overlying litter layer and the underlying wind blown silt materials. Earthworms' biomasses and functional group compositions, depth profiles of soil C contents, and total and organic matter-covered mineral surface areas are determined at different stages of invasion. We found that minerals' specific surface areas (SSA) in the A horizons decrease with greater degree of earthworm invasion. Furthermore, less fractions of mineral SSA were found to be coated with organic C in the soils with active earthworm populations. These observations appear to contradict another finding that amounts of crystalline Fe oxide and organically-complexed Fe increase with the greater earthworm population. The overall trend shows that earthworms' active mixing resulting in incorporating silt materials with low SSA from the underlying E horizons to the A horizons. We are currently investigating whether the increased crystalline Fe oxides and organically-complexed Fe pools with increasing earthworm population helped reducing the gradient of overall trend. Our study highlights the importance of earthworm

  6. Negative and positive interactions among plants: effects of competitors and litter on seedling emergence and growth of forest and grassland species.

    Science.gov (United States)

    Loydi, A; Donath, T W; Otte, A; Eckstein, R L

    2015-05-01

    Living plant neighbours, but also their dead aboveground remains (i.e. litter), may individually exert negative or positive effects on plant recruitment. Although living plants and litter co-occur in most ecosystems, few studies have addressed their combined effects, and conclusions are ambivalent. Therefore, we examined the response in terms of seedling emergence and growth of herbaceous grassland and forest species to different litter types and amounts and the presence of competitors. We conducted a pot experiment testing the effects of litter type (grass, oak), litter amount (low, medium, high) and interspecific competition (presence or absence of four Festuca arundinacea individuals) on seedling emergence and biomass of four congeneric pairs of hemicryptophytes from two habitat types (woodland, grassland). Interactions between litter and competition were weak. Litter presence increased competitor biomass. It also had positive effects on seedling emergence at low litter amounts and negative effects at high litter amounts, while competition had no effect on seedling emergence. Seedling biomass was negatively affected by the presence of competitors, and this effect was stronger in combination with high amounts of litter. Litter affected seedling emergence while competition determined the biomass of the emerged individuals, both affecting early stages of seedling recruitment. High litter accumulation also reduced seedling biomass, but this effect seemed to be additive to competitor effects. This suggests that live and dead plant mass can affect species recruitment in natural systems, but the mechanisms by which they operate and their timing differ.

  7. Spectral Evidence of In-Situ Regulatory Mechanisms on Chemical Speciation of Lead/Cadmium Affected by Dissolved Organic Matter Extracted from Rhizosphere Loess of Calendula Officinalis Seedling%金盏菊根际圈黄土溶解性有机质对Pb/Cd赋存形态原位调控机制的光谱学证据

    Institute of Scientific and Technical Information of China (English)

    范春辉; 徐慧荟; 张颖超

    2016-01-01

    The various characteristics of DOM have great impact on the transformation process of contaminants in soil due to the generation of the feedback regulation in cycles of plant,Rhizosphere soil and environmental contaminants.Currently,more at-tention was paid on contaminants behaviors of adsorption,transformation,accumulation and detoxification than DOM derived from Rhizosphere soil.The chemical speciation of lead/cadmium and growth efficiency related variations were revealed in the growth process of Calendulaofficinalis seedlings,and the spectral characteristics of DOM in Rhizosphere loess were discussed with UV,FT-IR and 3D-EEMs spectra.The results showed:the dominant contents of lead/cadmium are in residual and ex-changeable speciation,and the exchangeable contents increase greatly after the growth of Calendula officinalis seedlings.It causes negative effects on the height and emergency rate of Calendulaofficinalis seedlings with lead/cadmium,and the Calen-dulaofficinalis is able to positively improve loess characteristics.The root of Calendulaofficinalis appears to be longer,thin-ner and flexuous.The maximum absorption band of DOM in UV spectra locates in 200~240 nm,and the sharper and greater in-tensity of peaks can be detected under lead/cadmium stress.The absorption peaks in FT-IR spectra move from 3 444 and 1 637 to 3 440 and 1 645 cm-1 ,respectively,indicating the combination effects between metal ions and functional groups of—OH and C—O .The dominant fluorescence peaks of DOM are found to be aroundλex/em=240/430,described as fulvic-acid like compo-nents,and metals in loess affect more on peaks intensity than locations.The characteristics of DOM in Rhizosphere loess of Calendula officinalis seedlings contain much micro-eco-environmental information,and the spectral approaches are efficient to reveal the relationship between DOM and chemical speciation of lead/cadmium.%在污染场地植物修复过程中,植物根系通过释放活性分泌物主动

  8. Fungi of the genus Fusarium as pathogens of soybean seedlings

    Directory of Open Access Journals (Sweden)

    Joanna Marcinkowska

    2013-12-01

    Full Text Available Twenty isolates of fungi of the genus Fusarium collected in the period 1980-1982 from various organs of diseased soybean plants were investigated. Eight of them proved pathogenic to soybean seedlings. The species F. culmorum was most numerously represented among the isolated (4 of 8 pathogens. Isolates of F. sambucinum were also pathogenic (2 of 4 and those of F. soloni (1 of 3, too. The only isolate of F. avenaceum also caused seedling blight. Two isolates of F. oxysporum and two of F. arthrosporioides were not pathogenic. Numerous isolates affected seed gernination and one greatly inhibited growth of the infected seedlings. Pathogenicity was tested in the laboratory in Petri plates on isolate cultures and on filter paper imbibed with fungal inoculum and, in the greenhouse on a peat and perlite substrate. The degree of infection and the character of the disease symptoms depended on the experimental conditions. The results of experiments in plates and in the greenhouse supplemented one another.

  9. GAS EXCHANGE AND CARBOHYDRATE PARTITIONING IN COFFEE SEEDLINGS UNDER WATERLOGGING

    Directory of Open Access Journals (Sweden)

    Helbert Rezende de Oliveira Silveira

    2015-04-01

    Full Text Available Irrigation has enhanced coffee production in several regions of Brazil. However, with the increase in irrigated crop areas, problems related to the frequent and poorly planned usage of irrigation may arise. Since there are few studies related to the physiological alterations in coffee plants exposed to water excess, we evaluated the effects of waterlogging on metabolism and partitioning of carbohydrates, levels of photosynthetic pigments and gas exchange in seedlings of two commercial coffee cultivars (Mundo Novo and Catuaí. After acclimation, seedlings with eight pairs of fully expanded leaves were cultivated under three water availability conditions: field capacity, intermittent waterlogging and continuous waterlogging. Gas exchange and the levels of chlorophyll, carotenoids and carbohydrates were evaluated during the five months after the beginning of the treatments. Waterlogging reduced the rates of photosynthesis and transpiration, leading to lower activity of the carboxylative step of photosynthesis and culminating in the reduction of carbohydrate partitioning in coffee seedlings. Although many physiological parameters were affected by waterlogging, the cultivars in our study survived for five months under stressful conditions.

  10. Controlled release fertilizer improves quality of container longleaf pine seedlings

    Science.gov (United States)

    R. Kasten Dumroese; Jeff Parkhurst; James P. Barnett

    2005-01-01

    In an operational trial, increasing the amount of nitrogen (N) applied to container longleaf pine seedlings by incorporating controlled release fertilizer (CRF) into the media improved seedling growth and quality. Compared with control seedlings that received 40 mg N, seedlings receiving 66 mg N through CRF supplemented with liquid fertilizer had needles that were 4 in...

  11. Evaluation of spectral light management on growth of container-grown willow oak, nuttall oak and summer red maple

    Science.gov (United States)

    Plant response to blue, red, gray or black shade cloth was evaluated with willow oak (Quercus phellos L.), Nuttall oak (Quercus nuttallii Palmer, Nuttall) and Summer Red maple (Acer rubrum L. ‘Summer Red’) liners. Light transmitted through the colored shade cloth had no influence on germination of ...

  12. Linking environmental gradients, species composition, and vegetation indicators of sugar maple health in the northeastern United States

    Science.gov (United States)

    Stephen B. Horsley; Scott W. Bailey; Todd E. Ristau; Robert P. Long; Richard A. Hallett

    2008-01-01

    Sugar maple (Acer saccharum Marsh.) decline has occurred throughout its range over the past 50 years, although decline symptoms are minimal where nutritional thresholds of Ca, Mg, and Mn are met. Here, we show that availability of these elements also controls vascular plant species composition in northern hardwood stands and we identify indicator...

  13. Relationship between Tree Value, Diameter, and Age in High-Quality Sugar Maple (Acer saccharum) on the Menominee Reservation, Wisconsin

    Science.gov (United States)

    Daniel C. Dey; John Dwyer; Jan Wiedenbeck

    2017-01-01

    Guidelines for managing sugar maple-dominated forests by the single-tree selection method are well established and widely adopted. The forests of the Menominee Tribe in Wisconsin provide an opportunity to validate current guidelines by testing tree value and size/age relationships in forests that have substantially older and larger high-quality trees than can be found...

  14. Surface morphology of polyethylene glycol films produced by matrix-assisted pulsed laser evaporation (MAPLE): Dependence on substrate temperature

    DEFF Research Database (Denmark)

    Rodrigo, K.; Czuba, P.; Toftmann, B.;

    2006-01-01

    The dependence of the surface morphology on the substrate temperature during film deposition was investigated for polyethylene glycol (PEG) films by matrix-assisted pulsed laser evaporation (MAPLE). The surface structure was studied with a combined technique of optical imaging and AFM measurements...

  15. High fluence deposition of polyethylene glycol films at 1064 nm by matrix assisted pulsed laser evaporation (MAPLE)

    DEFF Research Database (Denmark)

    Purice, Andreea; Schou, Jørgen; Kingshott, P.;

    2007-01-01

    Matrix assisted pulsed laser evaporation (MAPLE) has been applied for deposition of thin polyethylene glycol (PEG) films with infrared laser light at 1064 nm. We have irradiated frozen targets (of 1 wt.% PEG dissolved in water) and measured the deposition rate in situ with a quartz crystal 2...

  16. Acute O 3 damage on first year coppice sprouts of aspen and maple sprouts in an open-air experiment.

    Science.gov (United States)

    Darbah, Joseph N T; Jones, Wendy S; Burton, Andrew J; Nagy, John; Kubiske, Mark E

    2011-09-01

    We studied the effect of high ozone (O(3)) concentration (110-490 nmol mol(-1)) on regenerating aspen (Populus tremuloides) and maple (Acer saccharum) trees at an open-air O(3) pollution experiment near Rhinelander WI USA. This study is the first of its kind to examine the effects of acute O(3) exposure on aspen and maple sprouts after the parent trees, which were grown under elevated O(3) and/or CO(2) for 12 years, were harvested. Acute O(3) damage was not uniform within the crowns of aspen suckers; it was most severe in the mature, fully expanded photosynthesizing leaves. Young expanding leaves showed no visible signs of acute O(3) damage contrary to expectations. Stomatal conductance played a primary role in the severity of acute O(3) damage as it directly controlled O(3) uptake. Maple sprouts, which had lower stomatal conductance, smaller stomatal aperture, higher stomatal density and larger leaf surface area, were tolerant of acute O(3) exposure. Moreover, elevated CO(2) did not ameliorate the adverse effects of acute O(3) dose on aspen and maple sprouts, in contrast to its ability to counteract the effects of long-term chronic exposure to lower O(3) levels.

  17. Acute O3 damage on first year coppice sprouts of aspen and maple sprouts in an open-air experiment

    Energy Technology Data Exchange (ETDEWEB)

    Darbah, J.N.; Nagy, J.; Jones, W. S.; Burton, A. J.; Kubiske, M. E.

    2011-10-01

    We studied the effect of high ozone (O{sub 3}) concentration (110-490 nmol mol{sup -1}) on regenerating aspen (Populus tremuloides) and maple (Acer saccharum) trees at an open-air O{sub 3} pollution experiment near Rhinelander WI USA. This study is the first of its kind to examine the effects of acute O{sub 3} exposure on aspen and maple sprouts after the parent trees, which were grown under elevated O{sub 3} and/or CO{sub 2} for 12 years, were harvested. Acute O{sub 3} damage was not uniform within the crowns of aspen suckers; it was most severe in the mature, fully expanded photosynthesizing leaves. Young expanding leaves showed no visible signs of acute O{sub 3} damage contrary to expectations. Stomatal conductance played a primary role in the severity of acute O{sub 3} damage as it directly controlled O{sub 3} uptake. Maple sprouts, which had lower stomatal conductance, smaller stomatal aperture, higher stomatal density and larger leaf surface area, were tolerant of acute O{sub 3} exposure. Moreover, elevated CO{sub 2} did not ameliorate the adverse effects of acute O{sub 3} dose on aspen and maple sprouts, in contrast to its ability to counteract the effects of long-term chronic exposure to lower O{sub 3} levels.

  18. Costs, yields, and revenues associated with thinning and clearcutting 60-year-old cherry-maple stands

    Science.gov (United States)

    Gary W. Miller; Raymond L. Sarles; Raymond L. Sarles

    1986-01-01

    Logging costs, product yields, and harvest revenues were determined for three thinning treatments (75, 60, and 45 percent residual stocking) and clearcutting in 60-year-old cherry-maple stands. The study area was logged by a three-man crew using chain saws and a wheeled skidder. Time study and yield data indicated that production rates and costs were similar among the...

  19. Wind-dispersed seed deposition patterns and seedling recruitment of Artemisia halodendron in a moving sandy land.

    Science.gov (United States)

    Li, Feng-Rui; Wang, Tao; Zhang, Ai-Sheng; Zhao, Li-Ya; Kang, Ling-Fen; Chen, Wen

    2005-07-01

    Artemisia halodendron is a native sub-shrub that occurs mainly in moving and semi-fixed sandy lands in Inner Mongolia, China. Information on the spatial patterns of wind-dispersed seed deposition and seedling recruitment of A. halodendron inhabiting moving sandy lands is very limited. The aim of this study was to examine wind-dispersed seed deposition patterns and post-dispersal recruitment of A. halodendron seedlings. * The spatial patterns of wind-dispersed seed deposition and seedling recruitment of A. halodendron were examined by investigating the numbers of deposited seeds, emerged and surviving seedlings using sampling points at a range of distances from the parent plant in eight compass directions for two consecutive growing seasons. * Wind-dispersed seed deposition showed considerable variation between directions and years. Wind transported A. halodendron seeds only a few meters away from the parent plant in all eight directions. Seedling emergence and establishment also showed between-direction and between-year variability, but the spatial pattern of seedling distribution differed from that of seed deposition. Only a very small fraction (seeds emerged in the field and survived for long enough to be included in our seedling censuses at the end of the growing season. * The spatial variation in wind speed and frequency strongly affects the pattern of seed deposition, although the variation in seed deposition does not determine the spatial pattern of seedling recruitment. Seeds of A. halodendron are not dispersed very well by wind. The low probability of recruitment success for A. halodendron seedlings suggests that this species does not rely on seedling recruitment for its persistence and maintenance of population.

  20. Cucumber Seedling Indoleacetaldehyde Oxidase 1

    Science.gov (United States)

    Bower, Peter J.; Brown, Hugh M.; Purves, William K.

    1978-01-01

    Extracts of light-grown Cucumis sativus L. seedlings catalyzed the oxidation of indole-3-acetaldehyde to indole-3-acetic acid. No added cofactors were required. Inhibitor studies indicated that the enzyme is a metalloflavoprotein. While indole-3-aldehyde, benzaldehyde, and phenylacetaldehyde partially inhibited the oxidation of indole-3-acetaldehyde, suggesting that they may serve as alternative substrates, it is proposed that indoleacetaldehyde is the major substrate in vivo. 2,4-Dichlorophenoxyacetic acid strongly inhibited the indoleacetaldehyde oxidase activity, and it is proposed that this enzyme may be subject in vivo to feedback inhibition by indole-3-acetic acid. The enzyme was activated by brief heating or by treatment with mercaptoethanol. PMID:16660220

  1. Effects of prolonged drought stress on Scots pine seedling carbon allocation.

    Science.gov (United States)

    Aaltonen, Heidi; Lindén, Aki; Heinonsalo, Jussi; Biasi, Christina; Pumpanen, Jukka

    2016-12-14

    As the number of drought occurrences has been predicted to increase with increasing temperatures, it is believed that boreal forests will become particularly vulnerable to decreased growth and increased tree mortality caused by the hydraulic failure, carbon starvation and vulnerability to pests following these. Although drought-affected trees are known to have stunted growth, as well as increased allocation of carbon to roots, still not enough is known about the ways in which trees can acclimate to drought. We studied how drought stress affects belowground and aboveground carbon dynamics, as well as nitrogen uptake, in Scots pine (Pinus sylvestris L.) seedlings exposed to prolonged drought. Overall 40 Scots pine seedlings were divided into control and drought treatments over two growing seasons. Seedlings were pulse-labelled with (13)CO2 and litter bags containing (15)N-labelled root biomass, and these were used to follow nutrient uptake of trees. We determined photosynthesis, biomass distribution, root and rhizosphere respiration, water potential, leaf osmolalities and carbon and nitrogen assimilation patterns in both treatments. The photosynthetic rate of the drought-induced seedlings did not decrease compared to the control group, the maximum leaf specific photosynthetic rate being 0.058 and 0.045 µmol g(-1) s(-1) for the drought and control treatments, respectively. The effects of drought were, however, observed as lower water potentials, increased osmolalities as well as decreased growth and greater fine root-to-shoot ratio in the drought-treated seedlings. We also observed improved uptake of labelled nitrogen from soil to needles in the drought-treated seedlings. The results indicate acclimation of seedlings to long-term drought by aiming to retain sufficient water uptake with adequate allocation to roots and root-associated mycorrhizal fungi. The plants seem to control water potential with osmolysis, for which sufficient photosynthetic capability is needed.

  2. Antimicrobial activity of biopolymeric thin films containing flavonoid natural compounds and silver nanoparticles fabricated by MAPLE: A comparative study

    Energy Technology Data Exchange (ETDEWEB)

    Cristescu, R., E-mail: rodica.cristescu@inflpr.ro [National Institute for Lasers, Plasma & Radiation Physics, Lasers Department, P.O. Box MG-36, Bucharest-Magurele (Romania); Visan, A.; Socol, G. [National Institute for Lasers, Plasma & Radiation Physics, Lasers Department, P.O. Box MG-36, Bucharest-Magurele (Romania); Surdu, A.V.; Oprea, A.E.; Grumezescu, A.M. [Faculty of Applied Chemistry and Materials Science, Politehnica University of Bucharest, 1–7 Polizu Street, Bucharest, 011061 Romania (Romania); Chifiriuc, M.C. [Microbiology Immunology Department, Faculty of Biology, Research Institute of the University of Bucharest - ICUB, Bucharest, 77206 (Romania); Boehm, R.D.; Yamaleyeva, D.; Taylor, M.; Narayan, R.J. [Department of Biomedical Engineering, University of North Carolina, Chapel Hill, NC (United States); Chrisey, D.B. [Department of Physics and Engineering Physics, Tulane University, New Orleans, LA (United States)

    2016-06-30

    Highlights: • We successfully deposited composite quercetin dehydrate-, resveratrol- and silver nanoparticle-polyvinylpyrrolidone thin coatings with chemical structure close to that of the starting materials by MAPLE. • Thin film morphology studies revealed a uniform surface without aggregates or grains on the top of the surface. • MAPLE-deposited thin films exhibited antibacterial activity against Gram-positive and Gram-negative bacterial strains. • We demonstrated the potential use of these hybrid systems and MAPLE deposition method for the development of new harmless, ecological antimicrobial strategies. - Abstract: The purpose of this study was to investigate the interactions between microorganisms, including the planktonic and adherent organisms, and biopolymer (polyvinylpyrrolidone), flavonoid (quercetin dihydrate and resveratrol)-biopolymer, and silver nanoparticles-biopolymer composite thin films that were deposited using matrix assisted pulsed laser evaporation (MAPLE). A pulsed KrF{sup *} excimer laser source was used to deposit the aforementioned composite thin films, which were characterized using Fourier transform infrared spectroscopy (FT-IR), infrared microscopy (IRM), scanning electron microscopy (SEM), Grazing incidence X-ray diffraction (GIXRD) and atomic force microscopy (AFM). The antimicrobial activity of thin films was quantified using an adapted disk diffusion assay against Gram-positive and Gram-negative bacteria strains. FT-IR, AFM and SEM studies confirmed that MAPLE may be used to fabricate thin films with chemical properties corresponding to the input materials as well as surface properties that are appropriate for medical use. The silver nanoparticles and flavonoid-containing films exhibited an antimicrobial activity both against Gram-positive and Gram-negative bacterial strains demonstrating the potential use of these hybrid systems for the development of novel antimicrobial strategies.

  3. Seed Mucilage Improves Seedling Emergence of a Sand Desert Shrub

    OpenAIRE

    Xuejun Yang; Baskin, Carol C.; Baskin, Jerry M.; Guangzheng Liu; Zhenying Huang

    2012-01-01

    The success of seedling establishment of desert plants is determined by seedling emergence response to an unpredictable precipitation regime. Sand burial is a crucial and frequent environmental stress that impacts seedling establishment on sand dunes. However, little is known about the ecological role of seed mucilage in seedling emergence in arid sandy environments. We hypothesized that seed mucilage enhances seedling emergence in a low precipitation regime and under conditions of sand buria...

  4. [Effects of aboveground and belowground competition between grass and tree on elm seedlings growth in Horqin Sandy Land].

    Science.gov (United States)

    Tang, Yi; Jiang, De-ming; Chen, Zhuo; Toshio, Oshida

    2011-08-01

    Elm sparse woodland steppe plays an important role in vegetation restoration and landscape protection in Horqin Sandy Land. In this paper, a two-factor and two-level field experiment was conducted to explore the effects of aboveground and belowground competition between grass and tree on the growth of elm seedlings in the Sandy Land. Five aspects were considered, i.e., seedling biomass, belowground biomass/aboveground biomass, stem height, ratio of root to stem, and leaf number. For the one-year-old elm seedlings, their biomass showed a trend of no competition > aboveground competition > full competition > belowground competition, belowground biomass / aboveground biomass showed a trend of belowground competition > full competition > no competition > aboveground competition, stem height showed a trend of aboveground competition > no competition > full competition > belowground competition, root/stem ratio showed a trend of belowground competition > full competition > no competition > aboveground competition, and leaf number showed a trend of aboveground competition > no competition > belowground competition > full competition. Belowground competition had significant effects on the growth of one-year-old elm seedlings, while aboveground competition did not have. Neither belowground competition nor aboveground competition had significant effects on the growth of two-year-old elm seedlings. It was suggested that in Horqin Sandy Land, grass affected the growth of elm seedlings mainly via below-ground competition, but the belowground competition didn' t affect the resource allocation of elm seedlings. With the age increase of elm seedlings, the effects of grass competition on the growth of elm seedlings became weaker.

  5. Physiological responses of seeds and seedlings of lettuce submitted to Philodendron bipinnatifidum extract

    Directory of Open Access Journals (Sweden)

    Tiago Zanatta Aumonde

    2013-12-01

    Full Text Available The work was conducted to evaluate the effect of different Philodendron bipinnatifidum Schott. extract concentrations on the physiology and enzymatic metabolism of lettuce seeds and seedlings. The treatments extracts of mature leaves at concentrations of 0, 6, 12, 25 and 50%. Were evaluated the germination, first count germination, speed and germination speed index, length of shoot and primary root, seedling total dry mass, electrical conductivity, chlorophyll content, activity of the enzymes ?-amilase, superoxide dismutase, catalase and ascorbarto peroxidase, lipid peroxidation, hydrogen peroxide content and seedling emergence, length of shoot and total dry mass of emerged seedlings. There was a reduction of germination, germination speed index and total dry mass by increasing the concentration of the extract. While the content of hydrogen peroxide, lipid peroxidation and activity of superoxide dismutase, catalase and peroxidase ascorbarto increased with concentration. The increasing of concentration the leaf extracts of the P. bipinnatifidum negatively affects the activity of the enzyme ?-amylase and causes increase in the activity of antioxidant enzymes, affecting the physiologic performance and growth of lettuce seedlings.

  6. Effects of rhizobacteria on the respiration and growth of Cerasus sachalinensis Kom. seedlings

    Energy Technology Data Exchange (ETDEWEB)

    Qin, S.; Zhou, W.; Li, Z.; Lyu, D.

    2016-11-01

    In this study, we investigated the influence of rhizosphere microorganisms on seed germination and root metabolism in Cerasus sachalinensis Kom. We inoculated C. sachalinensis plants with suspensions of dominant bacterial strains isolated from their rhizosphere. Four bacterial strains each with significant growth-promoting or growth-inhibiting effects were screened from the efficient root-colonizing microorganisms. The number of actinomycetes increased and that of fungi decreased significantly in the seedling rhizospheres after rhizobacteria treatment. The growth-promoting bacteria slightly affected the respiration rates and respiratory pathway enzymes, but significantly improved root viability, root carbohydrate concentration and seedling growth. Bacillus cereus, Staphylococcus sp. and Pseudomonas fluorescens were identified as the growth-promoting rhizobacteria; one strain could not be identified. After inoculation with the growth-inhibiting bacteria, the number of fungal colonies in the seedling rhizospheres increased and root viability and respiration rate as well as starch and sucrose accumulation in the roots significantly decreased. The glycolysis, pentose phosphate and alternative oxidase pathways became the major pathways of respiratory metabolism after inoculation with the growth-inhibiting bacteria. The height, leaf number, growth and dry weight of the seedlings decreased significantly in plants inoculated with the growth-inhibiting bacteria. Inoculation of C. sachalinensis rhizosphere with growth-promoting and growth-inhibiting bacteria affected the soil environmental factors such as microbial group composition, nutrient concentration and seedling biomass. (Author)

  7. Effects of rhizobacteria on the respiration and growth of Cerasus sachalinensis Kom. seedlings

    Directory of Open Access Journals (Sweden)

    Sijun Qin

    2016-06-01

    Full Text Available In this study, we investigated the influence of rhizosphere microorganisms on seed germination and root metabolism in Cerasus sachalinensis Kom. We inoculated C. sachalinensis plants with suspensions of dominant bacterial strains isolated from their rhizosphere. Four bacterial strains each with significant growth-promoting or growth-inhibiting effects were screened from the efficient root-colonizing microorganisms. The number of actinomycetes increased and that of fungi decreased significantly in the seedling rhizospheres after rhizobacteria treatment. The growth-promoting bacteria slightly affected the respiration rates and respiratory pathway enzymes, but significantly improved root viability, root carbohydrate concentration and seedling growth. Bacillus cereus, Staphylococcus sp. and Pseudomonas fluorescens were identified as the growth-promoting rhizobacteria; one strain could not be identified. After inoculation with the growth-inhibiting bacteria, the number of fungal colonies in the seedling rhizospheres increased and root viability and respiration rate as well as starch and sucrose accumulation in the roots significantly decreased. The glycolysis, pentose phosphate and alternative oxidase pathways became the major pathways of respiratory metabolism after inoculation with the growth-inhibiting bacteria. The height, leaf number, growth and dry weight of the seedlings decreased significantly in plants inoculated with the growth-inhibiting bacteria. Inoculation of C. sachalinensis rhizosphere with growth-promoting and growth-inhibiting bacteria affected the soil environmental factors such as microbial group composition, nutrient concentration and seedling biomass.

  8. Ostryopsis davidiana seedlings inoculated with ectomycorrhizal fungi facilitate formation of mycorrhizae on Pinus tabulaeformis seedlings.

    Science.gov (United States)

    Bai, Shu-Lan; Li, Guo-Lei; Liu, Yong; Kasten Dumroese, R; Lv, Rui-Heng

    2009-08-01

    Reforestation in China is important for reversing anthropogenic activities that degrade the environment. Pinus tabulaeformis is desired for these activities, but survival and growth of seedlings can be hampered by lack of ectomycorrhizae. When outplanted in association with Ostryopsis davidiana plants on reforestation sites, P. tabulaeformis seedlings become mycorrhizal and survival and growth are enhanced; without O. davidiana, pines often remain without mycorrhizae and performance is poorer. To better understand this relationship, we initiated an experiment using rhizoboxes that restricted root and tested the hypothesis that O. davidiana seedlings facilitated ectomycorrhizae formation on P. tabulaeformis seedlings through hyphal contact. We found that without O. davidiana seedlings, inocula of five indigenous ectomycorrhizal fungi were unable to grow and associate with P. tabulaeformis seedlings. Inocula placed alongside O. davidiana seedlings, however, resulted in enhanced growth and nutritional status of O. davidiana and P. tabulaeformis seedlings, and also altered rhizosphere pH and phosphatase activity. We speculate that these species form a common mycorrhizal network and this association enhances outplanting performance of P. tabulaeformis seedlings used for forest restoration.

  9. Effect of Acinetobacter sp on metalaxyl degradation and metabolite profile of potato seedlings (Solanum tuberosum L. alpha variety.

    Directory of Open Access Journals (Sweden)

    Fabiola G Zuno-Floriano

    Full Text Available One of the most serious diseases in potato cultivars is caused by the pathogen Phytophthora infestans, which affects leaves, stems and tubers. Metalaxyl is a fungicide that protects potato plants from Phytophthora infestans. In Mexico, farmers apply metalaxyl 35 times during the cycle of potato production and the last application is typically 15 days before harvest. There are no records related to the presence of metalaxyl in potato tubers in Mexico. In the present study, we evaluated the effect of Acinetobacter sp on metalaxyl degradation in potato seedlings. The effect of bacteria and metalaxyl on the growth of potato seedlings was also evaluated. A metabolite profile analysis was conducted to determine potential molecular biomarkers produced by potato seedlings in the presence of Acinetobacter sp and metalaxyl. Metalaxyl did not affect the growth of potato seedlings. However, Acinetobacter sp strongly affected the growth of inoculated seedlings, as confirmed by plant length and plant fresh weights which were lower in inoculated potato seedlings (40% and 27%, respectively compared to the controls. Acinetobacter sp also affected root formation. Inoculated potato seedlings showed a decrease in root formation compared to the controls. LC-MS/MS analysis of metalaxyl residues in potato seedlings suggests that Acinetobacter sp did not degrade metalaxyl. GC-TOF-MS platform was used in metabolic profiling studies. Statistical data analysis and metabolic pathway analysis allowed suggesting the alteration of metabolic pathways by both Acinetobacter sp infection and metalaxyl treatment. Several hundred metabolites were detected, 137 metabolites were identified and 15 metabolic markers were suggested based on statistical change significance found with PLS-DA analysis. These results are important for better understanding the interactions of putative endophytic bacteria and pesticides on plants and their possible effects on plant metabolism.

  10. Above-Ground Dimensions and Acclimation Explain Variation in Drought Mortality of Scots Pine Seedlings from Various Provenances

    OpenAIRE

    2016-01-01

    Seedling establishment is a critical part of the life cycle, thus seedling survival might be even more important for forest persistence under recent and future climate change. Scots pine forests have been disproportionally more affected by climate change triggered forest-dieback. Nevertheless, some Scots pine provenances might prove resilient to future drought events because of the species’ large distributional range, genetic diversity, and adaptation potential. However, there is a lack of kn...

  11. Effect of Acinetobacter sp on metalaxyl degradation and metabolite profile of potato seedlings (Solanum tuberosum L.) alpha variety.

    Science.gov (United States)

    Zuno-Floriano, Fabiola G; Miller, Marion G; Aldana-Madrid, Maria L; Hengel, Matt J; Gaikwad, Nilesh W; Tolstikov, Vladimir; Contreras-Cortés, Ana G

    2012-01-01

    One of the most serious diseases in potato cultivars is caused by the pathogen Phytophthora infestans, which affects leaves, stems and tubers. Metalaxyl is a fungicide that protects potato plants from Phytophthora infestans. In Mexico, farmers apply metalaxyl 35 times during the cycle of potato production and the last application is typically 15 days before harvest. There are no records related to the presence of metalaxyl in potato tubers in Mexico. In the present study, we evaluated the effect of Acinetobacter sp on metalaxyl degradation in potato seedlings. The effect of bacteria and metalaxyl on the growth of potato seedlings was also evaluated. A metabolite profile analysis was conducted to determine potential molecular biomarkers produced by potato seedlings in the presence of Acinetobacter sp and metalaxyl. Metalaxyl did not affect the growth of potato seedlings. However, Acinetobacter sp strongly affected the growth of inoculated seedlings, as confirmed by plant length and plant fresh weights which were lower in inoculated potato seedlings (40% and 27%, respectively) compared to the controls. Acinetobacter sp also affected root formation. Inoculated potato seedlings showed a decrease in root formation compared to the controls. LC-MS/MS analysis of metalaxyl residues in potato seedlings suggests that Acinetobacter sp did not degrade metalaxyl. GC-TOF-MS platform was used in metabolic profiling studies. Statistical data analysis and metabolic pathway analysis allowed suggesting the alteration of metabolic pathways by both Acinetobacter sp infection and metalaxyl treatment. Several hundred metabolites were detected, 137 metabolites were identified and 15 metabolic markers were suggested based on statistical change significance found with PLS-DA analysis. These results are important for better understanding the interactions of putative endophytic bacteria and pesticides on plants and their possible effects on plant metabolism.

  12. Effect of Acinetobacter sp on Metalaxyl Degradation and Metabolite Profile of Potato Seedlings (Solanum tuberosum L.) Alpha Variety

    Science.gov (United States)

    Zuno-Floriano, Fabiola G.; Miller, Marion G.; Aldana-Madrid, Maria L.; Hengel, Matt J.; Gaikwad, Nilesh W.; Tolstikov, Vladimir; Contreras-Cortés, Ana G.

    2012-01-01

    One of the most serious diseases in potato cultivars is caused by the pathogen Phytophthora infestans, which affects leaves, stems and tubers. Metalaxyl is a fungicide that protects potato plants from Phytophthora infestans. In Mexico, farmers apply metalaxyl 35 times during the cycle of potato production and the last application is typically 15 days before harvest. There are no records related to the presence of metalaxyl in potato tubers in Mexico. In the present study, we evaluated the effect of Acinetobacter sp on metalaxyl degradation in potato seedlings. The effect of bacteria and metalaxyl on the growth of potato seedlings was also evaluated. A metabolite profile analysis was conducted to determine potential molecular biomarkers produced by potato seedlings in the presence of Acinetobacter sp and metalaxyl. Metalaxyl did not affect the growth of potato seedlings. However, Acinetobacter sp strongly affected the growth of inoculated seedlings, as confirmed by plant length and plant fresh weights which were lower in inoculated potato seedlings (40% and 27%, respectively) compared to the controls. Acinetobacter sp also affected root formation. Inoculated potato seedlings showed a decrease in root formation compared to the controls. LC-MS/MS analysis of metalaxyl residues in potato seedlings suggests that Acinetobacter sp did not degrade metalaxyl. GC–TOF–MS platform was used in metabolic profiling studies. Statistical data analysis and metabolic pathway analysis allowed suggesting the alteration of metabolic pathways by both Acinetobacter sp infection and metalaxyl treatment. Several hundred metabolites were detected, 137 metabolites were identified and 15 metabolic markers were suggested based on statistical change significance found with PLS-DA analysis. These results are important for better understanding the interactions of putative endophytic bacteria and pesticides on plants and their possible effects on plant metabolism. PMID:22363586

  13. [Effect of synthetic cyclopentane beta,beta'-triketones on amino acid metabolism in roots of buckwheat (Fagopyrum esculentum Moench.) seedlings].

    Science.gov (United States)

    Demina, E A; Tishchenko, L Ia; Shestak, O P; Novikov, V L; Anisimov, M M

    2009-01-01

    Germination of buckwheat seeds in solutions of synthetic mono- and tricyclic cyclopentane-containing beta,beta'-triketones of various concentrations was accompanied by inhibition of seedling root growth and changes in the contents of glutamate, gamma-aminobutyric acid, proline, glutamine, and alanine. The monocyclic triketone also affected the amount of isoleucine. It is likely that the increase in proline content is a nonspecific response significant for enhancing stress tolerance in seedlings.

  14. Low Temperature Affects Stem Cell Maintenance in Brassica oleracea Seedlings

    NARCIS (Netherlands)

    Jonge, de Jennifer; Kodde, Jan; Severing, Edouard I.; Bonnema, Guusje; Angenent, Gerco C.; Immink, Richard G.H.; Groot, Steven P.C.

    2016-01-01

    Most of the above ground tissues in higher plants originate from stem cells located in the shoot apical meristem (SAM). Several plant species can suffer from spontaneous stem cell arrest resulting in lack of further shoot development. In Brassica oleracea this SAM arrest is known as blindness and oc

  15. Effect of petroleum products on mangrove seedlings

    Digital Repository Service at National Institute of Oceanography (India)

    Jagtap, T.G.; Untawale, A.G.

    seen. General damage in both the species were burning, yellowing and wilting of the leaves associated with root damage causing retardation of growth. Extensive leaf fall in Avicennia seedlings resulted in its mortality...

  16. Virulence of Fusarium species to alfalfa seedlings

    Directory of Open Access Journals (Sweden)

    Krnjaja Vesna

    2005-01-01

    Full Text Available In in vitro conditions, virulence of 91 isolates of species Fusarium genus (F. oxysporum, F. solani, F. acuminatum, F. equiseti, F. arthrosporioides, F. prolifera- tum, F. avenaceum, F. semitectum, F. tricinctum, F. sporotrichioides and F. graminearum towards alfalfa seedlings was investigated. Isolates of investigated species originated from diseased alfalfa plants collected at four locations in Serbia based on symptoms of wilting caused by Fusarium and root rotting. Pathogenicity and virulence of investigated isolates of Fusarium spp. were determined by visual evaluation of inoculated seedlings of cultivar K28 in laboratory conditions. All isolated of investigated species had pathogenic effect on alfalfa seedlings which expressed symptoms such as necrosis of root, moist rotting and "melting of seedlings". Colour of necrotic root tissue varied from light brown, brown lipstick red to explicit black, depending on the Fusarium species. Strong virulence was established in 48 isolates, medium virulence in 31 and weak virulence in 12 isolates.

  17. Virulence of Fusarium species to alfalfa seedlings

    Directory of Open Access Journals (Sweden)

    Krnjaja Vesna

    2005-01-01

    Full Text Available In in vitro conditions, virulence of 91 isolates of species Fusarium genus (F. oxysporum, F. solani, F. acuminatum, F. equiseti, F. arthrosporioides, F. proliferatum, F. avenaceum, F. semitectum, F. tricinctum, F. sporotrichioides and F. graminearum towards alfalfa seedlings was investigated. Isolates of investigated species originated from diseased alfalfa plants collected on four locations in Serbia based on symptoms of wilting caused by fusarium and root rotting. Pathogenicity and virulence of investigated isolates of Fusarium spp. were determined by visual evaluation of inoculated seedlings of cultivars K28 in laboratory conditions. All isolated of investigated species had pathogenic effect on alfalfa seedlings, which expressed symptoms such as necrosis of root, moist rotting and "melting of seedlings". Colour of necrotic root tissue varied from light brown, brown, lipstick red to explicit black, depending on the Fusarium species. Strong virulence was established in 48 isolates, medium virulence in 31 and weak virulence in 12 isolates.

  18. Morphoanatomy of Serjania communis Cambess. seedling (Sapindaceae

    Directory of Open Access Journals (Sweden)

    Willian Adriano Lira Lopes

    2015-07-01

    Full Text Available Serjania communis Cambess. (Sapindaceae is a plant with climbing habit and occurs relatively often in Paraná State, Brazil. The fruits were collected at the 'Parque dos Pioneiros' a remnant of subtropical forest in Maringá, Paraná State, Brazil. The seedlings obtained in the greenhouse were described according to traditional techniques in plant morphology. Seedlings were embedded in historesin and sectioned in rotation microtome. The fruit is the samaroid type, the seeds have about 3 mm in length and brown color. Seedlings are epigeal phanerocotylar. The seedlings have a hairy hypocotyl, foliaceous cotyledons, reduced epicotyl, and two opposite eophylls. The root is diarch, the hypocotyl shows root-stem transition structure, stem epicotyl, and dorsiventral and hypostomatous cotyledons and eophylls. 'Tirodendros' with 45 days of age do not develop cambial variant.

  19. Morphoanatomy of Serjania communis Cambess. seedling (Sapindaceae)

    OpenAIRE

    2015-01-01

    Serjania communis Cambess. (Sapindaceae) is a plant with climbing habit and occurs relatively often in Paraná State, Brazil. The fruits were collected at the 'Parque dos Pioneiros' a remnant of subtropical forest in Maringá, Paraná State, Brazil. The seedlings obtained in the greenhouse were described according to traditional techniques in plant morphology. Seedlings were embedded in historesin and sectioned in rotation microtome. The fruit is the samaroid type, the seeds have about 3 mm in l...

  20. High laser-fluence deposition of organic materials in water ice matrices by ''MAPLE''

    DEFF Research Database (Denmark)

    Christensen, Bo Toftmann; Rodrigo, K.; Schou, Jørgen

    2005-01-01

    Matrix assisted pulsed laser evaporation (MAPLE) is a deposition technique for organic material. Water ice was used as a matrix for the biotechnologically important guest material, polyethylene glycol (PEG), for concentrations from 0.5 to 4 wt.%. The target was irradiated with 6 ns laser pulses...... at 355 nm at a fluence of 2.5-12 J/cm(2). Even at this high fluence, Fourier transform infrared spectroscopy (FTIR) indicates a chemical structure of the deposit close to that of the un-irradiated PEG. Matrix assisted laser desorption and ionization (MALDI) and gel permeation chromatography (GPC) show...... that the mass distribution of the deposited PEG is similar to that of the starting material. Optical pictures of the films show particle structures of PEG of a size up to 5-10 mu m. The deposition rate measured with a quartz crystal microbalance is typically of the order of 1 ng/ (cm(2) shot). (c) 2005 Elsevier...

  1. A Maple package to find first order differential invariants of 2ODEs via a Darboux approach

    Science.gov (United States)

    Avellar, J.; Duarte, L. G. S.; da Mota, L. A. C. P.

    2014-01-01

    Here we present an implementation of a semi-algorithm to find elementary first order differential invariants (elementary first integrals) of a class of rational second order ordinary differential equations (rational 2ODEs). The algorithm was developed in Duarte and da Mota (2009) [18]; it is based on a Darboux-type procedure, and it is an attempt to construct an analog (generalization) of the method built by Prelle and Singer (1983) [6] for rational first order ordinary differential equations (rational 1ODEs). to deal, this time, with 2ODEs. The FiOrDi package presents a set of software routines in Maple for dealing with rational 2ODEs. The package presents commands permitting research investigations of some algebraic properties of the ODE that is being studied.

  2. MAPLE deposition of Mn(III) metalloporphyrin thin films: Structural, topographical and electrochemical investigations

    Science.gov (United States)

    Cristescu, R.; Popescu, C.; Popescu, A. C.; Grigorescu, S.; Mihailescu, I. N.; Ciucu, A. A.; Iordache, S.; Andronie, A.; Stamatin, I.; Fagadar-Cosma, E.; Chrisey, D. B.

    2011-04-01

    We report the deposition by MAPLE of metallized nanostructured (5,10,15,20-tetraphenyl)porphinato manganese(III) chloride thin films onto gold screen-printed electrodes, or Si substrates. The deposited nanostructures were characterized by atomic force microscopy and exhibited globular structures with average diameters decreasing with laser fluence. Raman spectroscopy showed that no major decomposition appeared. We have investigated the Mn(III)-metalloporphyrin thin films by cyclic voltammetry in order to evaluate the potential bio/chemosensing activity on dopamine neurotransmitter analyte. We have found that the manganese(III)-porphyrin is appropriate as a single mediator for dopamine sensing in the specific case of gold screen-printed electrodes.

  3. MAPLE deposition of Mn(III) metalloporphyrin thin films: Structural, topographical and electrochemical investigations

    Energy Technology Data Exchange (ETDEWEB)

    Cristescu, R., E-mail: rodica.cristescu@inflpr.ro [National Institute for Lasers, Plasma and Radiation Physics, Lasers Department, P.O. Box MG-36, Bucharest, Magurele (Romania); Popescu, C.; Popescu, A.C.; Grigorescu, S.; Mihailescu, I.N. [National Institute for Lasers, Plasma and Radiation Physics, Lasers Department, P.O. Box MG-36, Bucharest, Magurele (Romania); Ciucu, A.A. [University of Bucharest, Faculty of Chemistry, Bucharest (Romania); Iordache, S.; Andronie, A.; Stamatin, I. [University of Bucharest, 3Nano-SAE Research Center, P.O. Box MG-38, Bucharest, Magurele (Romania); Fagadar-Cosma, E. [Institute of Chemistry Timisoara of Romanian Academy, Department of Organic Chemistry, 300223 Timisoara (Romania); Chrisey, D.B. [Rensselaer Polytechnic Institute, Department of Materials Science and Engineering, Troy 12180-3590, NY (United States)

    2011-04-01

    We report the deposition by MAPLE of metallized nanostructured (5,10,15,20-tetraphenyl)porphinato manganese(III) chloride thin films onto gold screen-printed electrodes, or <1 1 1> Si substrates. The deposited nanostructures were characterized by atomic force microscopy and exhibited globular structures with average diameters decreasing with laser fluence. Raman spectroscopy showed that no major decomposition appeared. We have investigated the Mn(III)-metalloporphyrin thin films by cyclic voltammetry in order to evaluate the potential bio/chemosensing activity on dopamine neurotransmitter analyte. We have found that the manganese(III)-porphyrin is appropriate as a single mediator for dopamine sensing in the specific case of gold screen-printed electrodes.

  4. Two consecutive partial liver transplants in a patient with Classic Maple Syrup Urine Disease

    Directory of Open Access Journals (Sweden)

    H.L. Chin

    2015-09-01

    Full Text Available Maple syrup urine disease is caused by a deficiency in the branched chain ketoacid dehydrogenase (BCKAD complex. This results in the accumulation of branched chain amino acids (BCAA and branched chain ketoacids in the body. Even when aggressively treated with dietary restriction of BCAA, patients experience long term cognitive, neurological and psychosocial problems. Liver transplantation from deceased donors has been shown to be an effective modality in introducing adequate BCKAD activity, attaining a metabolic cure for patients. Here, we report the clinical course of the first known patient with classic MSUD who received two consecutive partial liver grafts from two different living non-carrier donors and his five year outcome posttransplant. We also show that despite the failure of the first liver graft, and initial acute cellular rejection of the second liver graft in our patient, his metabolic control remained good without metabolic decompensation.

  5. BAHAN AJAR KALKULUS 2 MENGGUNAKAN MACROMEDIA FLASH DAN MAPLE DI STKIP PGRI LUBUKLINGGAU

    Directory of Open Access Journals (Sweden)

    Retni Paradesa

    2013-09-01

    Full Text Available This research purposes to result calculus II instructional material using valid, practical, and has potential effect Macromedia Flash and Maple toward student’s learning result. Valid can be described from the validity assessment result based on content (in accordance with calculus II subject and construct (in accordance with media producing rule. It is practically described from the small group test result. Data collecting was carried out by document analysis and test. It was development research consist of three stages, i.e. analysis, design, and evaluation stage. The subject of the research was 28 second semester students in mathematics education program in STKIP PGRI Lubuklinggau. From the test teaching material potential effect towards the result can be gained 81.2 average welled categories.  Finally it can be concluded the effective developed teaching material in mathematic learning. Key Word: development research, calculus II

  6. Multifunctional thin films of lactoferrin for biochemical use deposited by MAPLE technique

    Science.gov (United States)

    Constantinescu, Catalin; Palla-Papavlu, Alexandra; Rotaru, Andrei; Florian, Paula; Chelu, Florica; Icriverzi, Madalina; Nedelcea, Anca; Dinca, Valentina; Roseanu, Anca; Dinescu, Maria

    2009-03-01

    Lactoferrin (Lf) is an iron-binding glycoprotein present in almost all mammalian secretions which plays an important role in host defense against microbial and viral infections. The protein has been reported to also have anti-inflammatory activity and antitumoral effects in vitro and in vivo. Thin films of Lf were deposited on silicon, quartz and Thermanox plastic coverslip substrates by Matrix Assisted Pulsed Laser Evaporation (MAPLE) technique, using a Nd:YAG laser working at 266 nm, at different laser fluences (0.1-0.8 J cm -2). The deposited layers have been characterized by Fourier Transformed Infra-Red spectroscopy (FTIR), and the morphology of the various substrates was investigated by Atomic Force Microscopy (AFM). The biocompatibility of lactoferrin thin films was evaluated for each substrate, by in vitro biochemical tests.

  7. Morphometric characteristics of the leaves of Greek maple (Acer heldreichii Orph in central Serbia

    Directory of Open Access Journals (Sweden)

    Perović Marko

    2007-01-01

    Full Text Available The taxonomic characteristics of Greek maple (Acer heldreichii Orph were studied based on the analysis of leaf characteristics, by comparative-morphological method. The study was performed at three localities in central Serbia: Goč, Jastrebac and Rudnik. 30 normally developed trees were selected per each locality, and 30 leaves were selected from each tree for the analysis. The study includes 8 measured and 15 derived characteristics of leaves. The study results were statistically processed by correlation analysis, analysis of variance and cluster-analysis. It is concluded that there are two varieties, var. heldreichii and var. macropterum. Four forms are set aside in the variety macropterum: f. typicum f. dissectum, f. Equiloba and f. rotundiloba. The populations are relatively homogeneous, and both varieties occur at all three localities in significant numbers.

  8. Optimization of ethanol production from hot-water extracts of sugar maple chips

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Jian; Liu, Shijie [Department of Paper and Bioprocess Engineering, College of Environmental Science and Forestry, State University of New York, 1 Forestry Drive, Syracuse, NY 13210 (United States)

    2009-11-15

    Hot-water extracts from sugar maple chips prior to papermaking was employed in this study to produce ethanol by Pichia stipitis 58784. The effects of several factors, seed culture age, fermentation time, inoculum quantity, agitation rate, percent extract, concentration of inorganic nitrogen source (NH{sub 4}){sub 2}SO{sub 4} and pH value, on ethanol production were investigated by orthogonal experiments. Orthogonal analysis shows that the optimal fermentation was obtained in the condition of 48-h seed culture, 120-h fermentation, 16% inoculum, 180 rpm, containing 30% extracts, 8% ammonium sulphate supplement and pH 5. This optimal condition was verified at 800-mL level in a 1.3 L fermentor. The ethanol yield reached 82.27% of the theoretical (20.57 g/L) after 120 h. (author)

  9. Damage reduction to ponderosa pine seedlings from northern pocket gophers by vegetation management through grass seeding and herbicide treatment

    Science.gov (United States)

    Engeman, Richard M.; Barnes, V.G.; Anthony, R.M.; Krupa, Heather W.

    1998-01-01

    2,4-D herbicide treatment was applied to 2 treatment units to remove the forbs that are the preferred food of pocket gophers. One of these units also was seeded with grasses prior to the 2,4-D treatment. The effect of 2,4-D and grass seeding plus 2,4-D treatments were compared to an untreated control unit. Long-term monitoring (7 yr) was conducted on the 3 units for vegetative cover (7 yr), pocket gopher activity, and individual survival times and time until gopher damage for 2 cohorts of seedlings (5 and 6 yrs). The 2,4-D treatments greatly reduced vegetative cover of the forbs and seeding increased grass cover on the unit receiving that treatment. Pocket gopher activity was reduced somewhat on the unit receiving only the 2,4-D treatment and more so on the unit receiving grass seeding and 2,4-D, although gophers remained active to some degree throughout the study. Both cohorts of seedlings for both treatments units showed greater average times until gopher damage over seedlings on the control unit. However, seedling survival from all sources of mortality was not positively affected by the treatments for the first cohort of seedlings. The 2,4-D treatment appeared to have killed some of the seedlings; however, seedlings that survived the treatment were in a situation where they were less likely to be damaged by gophers and seemed to have improved growth rates.

  10. Seedling diversity and spatially related regenaration dynamics in holly woodlands and surrounding habitats

    Directory of Open Access Journals (Sweden)

    S. Arrieta

    2001-06-01

    Full Text Available Spatial patterns of seedling distribution and diversity were analysed in small fragments of holly Ilex aquifolium L. woodlands and in their surrounding areas. Two sampling locations with similar structure were selected for this study: Oncala and Robregordo. They consist of nearly monospecific Ilex stands surrounded by grasslands with high scrub abundance.

    The seedling appearance of woody species was quantified from March to November 1998. Sampled areas were: 1 closed holly canopy; 2 open holly canopy or small forest gaps; 3 holly woodland edge; 4 surrounding grassland; 5 under isolated fleshy-fruited shrubs scattered over the grassland; 6 under dry-fruited shrubs and 7 the closest forest to the holly woodland. Additionally, a pine forest at a distance of 20 km from Oncala was sampled. In every area ten permanent 50 × 50 cm quadrats were fixed for monthly seedling control.

    The highest germination density occurs under the holly woodland, especially in closed canopy areas. Nevertheless, these closed woodlands neither maintain a great quantity of surviving seedlings nor a high diversity. Seedling density is considerable in canopy gaps, shrubs and forest edge, and these habitats have greater diversity values than understorey habitats. Fleshy-fruited shrubs maintain higher seedling densities and diversity than dry-fruited shrubs. Woody seedlings are rare over the grassland. The three non-holly forests studied have very similar seedling densities and diversity values, higher than those under closed-canopy holly.

    Regional differences are important for the numbers of seedlings surviving from previous years, which are scareer in Robregordo. However, little difference is observed in spatial patterns of seedling diversity between the two locations.

    We discuss a number of processes affecting seed rain density and differential mortality rates that could account for these spatial patterns, namely competition

  11. Nuclear microsatellite markers for population genetic studies in sugar maple (Acer saccharum Marsh.

    Directory of Open Access Journals (Sweden)

    Sudhir Khodwekar

    2015-12-01

    Full Text Available A set of seven new nuclear microsatellite markers (nSSRs was developedfor sugar maple (Acer saccharum Marsh. using paired-end Illumina sequencing. Out of 96 primers screened in a panel of six unrelated individuals, seven markers amplified polymorphic products. The utility of these markers, in addition to six already published microsatellites, for genetic variation and gene flow studies was assessed. Out of the seven newly developed markers, three amplified multiple fragments and were interpreted as dominant (absence/presence markers, while four markers amplified a maximum of two amplification products per sample. The six published microsatellites and three of the four newly developed markers showed regular segregation in an open-pollinated single tree progeny. Observed heterozygosity (Ho and expected heterozygosity (He in 48 individuals from one population ranged from 0.436 to 0.917 and from 0.726 to 0.894, respectively. Dominant markers revealed 64 variable positions and moderate genetic variation within the population (He = 0.102, Shannon’s I = 0.193. Paternity analyses in the program CERVUS at co-dominant markers showed effective dispersal of pollen in the sugar maple population both at 95% and 80% confidence levels. Dependent on the confidence level, the mean pollen dispersal distance within the population ranged from 33.25 m to 38.75 m and gene flow from utside the stand from 78% to 82%. The absence of fine-scale Spatial Genetic Structure (SGS suggested effective dispersal of both seeds and pollen.

  12. Soybean cultivars 'Williams 82' and 'Maple Arrow' produce both urea and ammonia during ureide degradation.

    Science.gov (United States)

    Todd, Christopher D; Polacco, Joe C

    2004-04-01

    The ability of two soybean (Glycine max L. [Merrill]) cultivars, 'Williams 82' and 'Maple Arrow', which were reported to use different ureide degradation pathways, to degrade the ureides allantoin and allantoate was investigated. Protein fractions and total leaf homogenates from the fourth trifoliate leaves of both cultivars were examined for the ability to evolve either (14)CO(2) or [(14)C]urea from (14)C-labelled ureides in the presence of various inhibitors. (14)CO(2) evolution from [2,7-(14)C]allantoate was catalysed by 25-50% saturated ammonium sulphate fractions of both cultivars. This activity was inhibited by acetohydroxamate (AHA), which has been used to inhibit plant ureases, but not by phenylphosphorodiamidate (PPD), a more specific urease inhibitor. Thus, in both cultivars, allantoate may be metabolized by allantoate amidohydrolase. This activity was sensitive to EDTA, consistent with previous reports demonstrating that allantoate amidohydrolase requires manganese for full activity. Total leaf homogenates of both cultivars evolved both (14)CO(2) and [(14)C]urea from [2,7-(14)C] (ureido carbon labelled) allantoin, not previously reported in either 'Williams 82' or in 'Maple Arrow'. In situ leaf degradation of (14)C-labelled allantoin confirmed that both urea and CO(2)/NH(3) are direct products of ureide degradation. Growth of plants in the presence of PPD under fixing and non-fixing conditions caused urea accumulation in both cultivars, but did not have a significant impact on total seed nitrogen. Urea levels were higher in N-fixing plants of both cultivars. Contrary to previous reports, no significant biochemical difference was found in the ability of these two cultivars to degrade ureides under the conditions used.

  13. PSsolver: A Maple implementation to solve first order ordinary differential equations with Liouvillian solutions

    Science.gov (United States)

    Avellar, J.; Duarte, L. G. S.; da Mota, L. A. C. P.

    2012-10-01

    We present a set of software routines in Maple 14 for solving first order ordinary differential equations (FOODEs). The package implements the Prelle-Singer method in its original form together with its extension to include integrating factors in terms of elementary functions. The package also presents a theoretical extension to deal with all FOODEs presenting Liouvillian solutions. Applications to ODEs taken from standard references show that it solves ODEs which remain unsolved using Maple's standard ODE solution routines. New version program summary Program title: PSsolver Catalogue identifier: ADPR_v2_0 Program summary URL: http://cpc.cs.qub.ac.uk/summaries/ADPR_v2_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 2302 No. of bytes in distributed program, including test data, etc.: 31962 Distribution format: tar.gz Programming language: Maple 14 (also tested using Maple 15 and 16). Computer: Intel Pentium Processor P6000, 1.86 GHz. Operating system: Windows 7. RAM: 4 GB DDR3 Memory Classification: 4.3. Catalogue identifier of previous version: ADPR_v1_0 Journal reference of previous version: Comput. Phys. Comm. 144 (2002) 46 Does the new version supersede the previous version?: Yes Nature of problem: Symbolic solution of first order differential equations via the Prelle-Singer method. Solution method: The method of solution is based on the standard Prelle-Singer method, with extensions for the cases when the FOODE contains elementary functions. Additionally, an extension of our own which solves FOODEs with Liouvillian solutions is included. Reasons for new version: The program was not running anymore due to changes in the latest versions of Maple. Additionally, we corrected/changed some bugs/details that were hampering the smoother functioning of the routines. Summary

  14. Contribution of the diffusion-weighted MRI in the diagnosis and follow-up of encephalopathy caused by maple syrup urine disease in a full-term newborn

    Energy Technology Data Exchange (ETDEWEB)

    Ferraz-Filho, Jose Roberto Lopes; Floriano, Valdeci Helio; Quirici, Marcelo Bianco; Souza, Antonio Soares [Faculdade de Medicina de Sao Jose do Rio Preto (FAMERP), SP (Brazil). Dept. de Radiologia; Albuquerque, Regina Pires de [Faculdade de Medicina de Sao Jose do Rio Preto (FAMERP), SP (Brazil). Dept. de Pediatria

    2009-07-01

    The purpose of this case report is to show conventional MRI and diffusion-weighted imaging (DWI) findings of the different evolutionary phases in MSUD (Maple syrup urine disease) of a newborn that evolved with brain white matter lesions (author)

  15. Sensitivity of cold acclimation to elevated autumn temperature in field-grown Pinus strobus seedlings

    Directory of Open Access Journals (Sweden)

    Christine Yao-Yun Chang

    2015-03-01

    Full Text Available Climate change will increase autumn air temperature, while photoperiod decrease will remain unaffected. We assessed the effect of increased autumn air temperature on timing and development of cold acclimation and freezing resistance in Eastern white pine (EWP, Pinus strobus under field conditions. For this purpose we simulated projected warmer temperatures for southern Ontario in a Temperature Free-Air-Controlled Enhancement (T-FACE experiment and exposed EWP seedlings to ambient (Control or elevated temperature (ET, +1.5°C/+3°C during day/night. Photosynthetic gas exchange, chlorophyll fluorescence, photoprotective pigments, leaf non-structural carbohydrates (NSC, and cold hardiness were assessed over two consecutive autumns. Nighttime temperature below 10°C and photoperiod below 12h initiated downregulation of assimilation in both treatments. When temperature further decreased to 0°C and photoperiod became shorter than 10h, downregulation of the light reactions and upregulation of photoprotective mechanisms occurred in both treatments. While ET seedlings did not delay the timing of the downregulation of assimilation, stomatal conductance in ET seedlings was decreased by 20-30% between August and early October. In both treatments leaf NSC composition changed considerably during autumn but differences between Control and ET seedlings were not significant. Similarly, development of freezing resistance was induced by exposure to low temperature during autumn, but the timing was not delayed in ET seedlings compared to Control seedlings. Our results indicate that EWP is most sensitive to temperature changes during October and November when downregulation of photosynthesis , enhancement of photoprotection, synthesis of cold-associated NSCs and development of freezing resistance occur. However, we also conclude that the timing of the development of freezing resistance in EWP seedlings is not affected by moderate temperature increases used in our

  16. Seedling establishment in a masting desert shrub parallels the pattern for forest trees

    Science.gov (United States)

    Meyer, Susan E.; Pendleton, Burton K.

    2015-05-01

    The masting phenomenon along with its accompanying suite of seedling adaptive traits has been well studied in forest trees but has rarely been examined in desert shrubs. Blackbrush (Coleogyne ramosissima) is a regionally dominant North American desert shrub whose seeds are produced in mast events and scatter-hoarded by rodents. We followed the fate of seedlings in intact stands vs. small-scale disturbances at four contrasting sites for nine growing seasons following emergence after a mast year. The primary cause of first-year mortality was post-emergence cache excavation and seedling predation, with contrasting impacts at sites with different heteromyid rodent seed predators. Long-term establishment patterns were strongly affected by rodent activity in the weeks following emergence. Survivorship curves generally showed decreased mortality risk with age but differed among sites even after the first year. There were no detectable effects of inter-annual precipitation variability or site climatic differences on survival. Intraspecific competition from conspecific adults had strong impacts on survival and growth, both of which were higher on small-scale disturbances, but similar in openings and under shrub crowns in intact stands. This suggests that adult plants preempted soil resources in the interspaces. Aside from effects on seedling predation, there was little evidence for facilitation or interference beneath adult plant crowns. Plants in intact stands were still small and clearly juvenile after nine years, showing that blackbrush forms cohorts of suppressed plants similar to the seedling banks of closed forests. Seedling banks function in the absence of a persistent seed bank in replacement after adult plant death (gap formation), which is temporally uncoupled from masting and associated recruitment events. This study demonstrates that the seedling establishment syndrome associated with masting has evolved in desert shrublands as well as in forests.

  17. Fertility-dependent effects of ectomycorrhizal fungal communities on white spruce seedling nutrition.

    Science.gov (United States)

    Smith, Alistair J H; Potvin, Lynette R; Lilleskov, Erik A

    2015-11-01

    Ectomycorrhizal fungi (EcMF) typically colonize nursery seedlings, but nutritional and growth effects of these communities are only partly understood. To examine these effects, Picea glauca seedlings collected from a tree nursery naturally colonized by three dominant EcMF were divided between fertilized and unfertilized treatments. After one growing season seedlings were harvested, ectomycorrhizas identified using DNA sequencing, and seedlings analyzed for leaf nutrient concentration and content, and biomass parameters. EcMF community structure-nutrient interactions were tested using nonmetric multidimensional scaling (NMDS) combined with vector analysis of foliar nutrients and biomass. We identified three dominant species: Amphinema sp., Atheliaceae sp., and Thelephora terrestris. NMDS + envfit revealed significant community effects on seedling nutrition that differed with fertilization treatment. PERMANOVA and regression analyses uncovered significant species effects on host nutrient concentration, content, and stoichiometry. Amphinema sp. had a significant positive effect on phosphorus (P), calcium and zinc concentration, and P content; in contrast, T. terrestris had a negative effect on P concentration. In the unfertilized treatment, percent abundance of the Amphinema sp. negatively affected foliar nitrogen (N) concentration but not content, and reduced foliar N/P. In fertilized seedlings, Amphinema sp. was positively related to foliar concentrations of N, magnesium, and boron, and both concentration and content of manganese, and Atheliaceae sp. had a negative relationship with P content. Findings shed light on the community and species effects on seedling condition, revealing clear functional differences among dominants. The approach used should be scalable to explore function in more complex communities composed of unculturable EcMF.

  18. Effects of methyl jasmonate on accumulation of flavonoids in seedlings of common buckwheat (Fagopyrum esculentum Moench).

    Science.gov (United States)

    Horbowicz, M; Wiczkowski, W; Koczkodaj, Danuta; Saniewski, M

    2011-09-01

    The jasmonates, which include jasmonic acid and its methyl ester (MJ), play a central role in regulating the biosynthesis of many secondary metabolites, including flavonoids, and also are signaling molecules in environmental stresses. Synthesis of anthocyanins pigments is a final part of flavonoids pathway route. Accumulation of the pigments in young seedlings is stimulated by various environmental stresses, such as high-intensity light, wounding, pathogen attack, drought, sugar and nutrient deficiency. The anthocyanins take part in defense system against excess of light and UV-B light, and therefore it is probably main reason why young plant tissues accumulate enlarged levels of the pigments. The effects of exogenously applied MJ on level of anthocyanins, glycosides of apigenin, luteolin, quercetin and proanthocyanidins in seedlings of common buckwheat (Fagopyrum esculentum Moench) were studied. MJ decreased contents of all the found cyanidin glycosides and its aglycone in hypocotyls of buckwheat seedlings. However contents of particular anthocyanins in cotyledons of buckwheat seedlings treated with the plant hormone were not significantly different from the control. Applied doses of MJ did not affect levels of quercetin, apigenin and luteolin glycosides in the analyzed parts of buckwheat seedlings: cotyledons and hypocotyls. On the other hand, treatment of buckwheat seedlings with MJ clearly stimulated of proanthocyanidins biosynthesis in hypocotyls. We suggest that methyl jasmonate induces in hypocotyls of buckwheat seedlings the leucocyanidin reductase or anthocyanidin reductase, possible enzymes in proanthocyanidins synthesis, and/or inhibits anthocyanidin synthase, which transforms leucocyanidin into cyanidin. According to our knowledge this is the first report regarding the effect of methyl jasmonate on enhancing the accumulation of proanthocyanidins in cultivated plants.

  19. Herbivore-induced shifts in carbon and nitrogen allocation in red oak seedlings

    Science.gov (United States)

    Christopher J. Frost; Mark D. Hunter

    2008-01-01

    A dual-isotope, microcosm experiment was conducted with Quercus rubra (red oak) seedlings to test the hypothesis that foliar herbivory would increase belowground carbon allocation (BCA), carbon (C) rhizodeposition and nitrogen (N) uptake. Plant BCA links soil ecosystems to aboveground processes and can be affected by insect herbivores, though the...

  20. In Vivo Effects of Barbituates on Seed Germination and Seedling Growth.

    Science.gov (United States)

    Kordan, H. A.

    1984-01-01

    A simple, low-cost experimental system can be used to demonstrate the "in vivo" effects of barbituates on seed germination and seedling growth behavior in different plant species. Lipid solubility and concentration of individual barbituates both affect the response. List of materials needed, procedures used, and typical results obtained are…

  1. In Vivo Effects of Barbituates on Seed Germination and Seedling Growth.

    Science.gov (United States)

    Kordan, H. A.

    1984-01-01

    A simple, low-cost experimental system can be used to demonstrate the "in vivo" effects of barbituates on seed germination and seedling growth behavior in different plant species. Lipid solubility and concentration of individual barbituates both affect the response. List of materials needed, procedures used, and typical results obtained are…

  2. HEAVY METALS IN MAPLE AND DANDELION LEAVES FROM DIFERENT LAND-USE AREAS IN MOSCOW ’S EASTERN DISTRICT

    Directory of Open Access Journals (Sweden)

    Dmitry V. Vlasov

    2015-01-01

    Full Text Available This article is based on extensive biogeochemical research conducted in Moscow’s Eastern Administrative District, where motor-vehicle traffic and heavy industry have resulted in some of the highest levels of pollution in the city. For this study, 26 samples of maple leaves (Acer platanoides and 49 samples of dandelion leaves (Taraxacum officinalewere collected on a regular grid at 500–700 m intervals. Concentrations of Fe, Mn, Mo, Cd, Pb, Zn, Cu, As and Sb in these plants were measured using atomic absorption spectrometry after washing, drying and HNO3 + H2O2 digestion. Maples accumulated Sb9,7As4,6Mo2,2Fe2,0Zn1,5 Pb1,4Cu1,2, while dandelions accumulated Mo12,7Pb4,9Cd4,4Fe4,3As3,9Sb2,7Cu1,4 — normalized to concentrations in background samples from an unpolluted site west from Moscow. The plants’ geochemical specialization was detected and compared in the following land-use areas: industrial, traffic, recreational, agricultural, and high-, mid-, and low-rise residential development. For maples, the highest concentration factor levels were found in industrial areas, with accumulations of Sb19As2,4Mo1,7Zn1,7Fe1,5Cu1,4Pb1,4. These levels were 2–5 timeslower for maples in other land-use areas. Dandelions and maples do not accumulate Mnbecause of antagonism between Zn, Mo and Mn in soils. Copper is not concentrated byherbaceous species because of antagonism between Mo and Cu. Differences in  eochemical specialization were shown using the Sb/Mo ratio: in dandelions this was 5 times lower than in background samples, while in maples it was 4.5 times higher. A Zv ratio was used to evaluate the intensity of biogeochemical transformation in urban plants. The highest Zv ratios were found in plants near industrial zones and large roads.

  3. Co-existence of phenylketonuria either with maple syrup urine disease or Sandhoff disease in two patients from Iran: emphasizing the role of consanguinity.

    Science.gov (United States)

    Abiri, Maryam; Talebi, Saeed; Uitto, Jouni; Youssefian, Leila; Vahidnezhad, Hassan; Shirzad, Tina; Salehpour, Shadab; Zeinali, Sirous

    2016-10-01

    Most inborn errors of metabolism (IEMs) are inherited in an autosomal recessive manner. IEMs are one of the major concerns in Iran due to its extensive consanguineous marriages. Herein, we report two patients with two co-existent IEMs: a girl affected by classic phenylketonuria (PKU) and maple syrup urine disease (MSUD) and a male patient affected with Sandhoff disease and PKU, where Sandhoff disease was suspected due to the presence of a cherry-red spot in the eyes at 6 months which is unrelated to PKU. Sequencing of candidate genes in the first patient revealed one novel and three recurrent compound heterozygous mutations of p.Ser231Pro and p.Ala300Ser in the PAH gene and p.Glu330Lys and p.Arg170Cys mutations in the BCKDHB gene. Genetic testing results in the second patient showed previously reported homozygous mutations of p.Arg261Gln in the PAH and p.Arg533Cys mutation in the HEXB gene. Genetic testing confirmed the clinical diagnosis of both diseases in both patients. To the best of our knowledge; this is the first report of the co-existence of two distinct genetic disorders in two individuals from Iran. Co-existent different IEMs in patients complicated the clinical diagnosis and management of the diseases.

  4. Above-Ground Dimensions and Acclimation Explain Variation in Drought Mortality of Scots Pine Seedlings from Various Provenances.

    Science.gov (United States)

    Seidel, Hannes; Menzel, Annette

    2016-01-01

    Seedling establishment is a critical part of the life cycle, thus seedling survival might be even more important for forest persistence under recent and future climate change. Scots pine forests have been disproportionally more affected by climate change triggered forest-dieback. Nevertheless, some Scots pine provenances might prove resilient to future drought events because of the species' large distributional range, genetic diversity, and adaptation potential. However, there is a lack of knowledge on provenance-specific survival under severe drought events and on how acclimation alters survival rates in Scots pine seedlings. We therefore conducted two drought-induced mortality experiments with potted Scots pine seedlings in a greenhouse. In the first experiment, 760 three-year-old seedlings from 12 different provenances of the south-western distribution range were subjected to the same treatment followed by the mortality experiment in 2014. In the second experiment, we addressed the question of whether acclimation to re-occurring drought stress events and to elevated temperature might decrease mortality rates. Thus, 139 four-year-old seedlings from France, Germany, and Poland were subjected to different temperature regimes (2012-2014) and drought treatments (2013-2014) before the mortality experiment in 2015. Provenances clearly differed in their hazard of drought-induced mortality, which was only partly related to the climate of their origin. Drought acclimation decreased the hazard of drought-induced mortality. Above-ground dry weight and height were the main determinants for the hazard of mortality, i.e., heavier and taller seedlings were more prone to mortality. Consequently, Scots pine seedlings exhibit a considerable provenance-specific acclimation potential against drought mortality and the selection of suitable provenances might thus facilitate seedling establishment and the persistence of Scots pine forest.

  5. Ecophysiological variation in two provenances of Pinus flexilis seedlings across an elevation gradient from forest to alpine.

    Science.gov (United States)

    Reinhardt, Keith; Castanha, Cristina; Germino, Matthew J; Kueppers, Lara M

    2011-06-01

    Climate change is predicted to cause upward shifts in forest tree distributions, which will require seedling recruitment beyond current forest boundaries. However, predicting the likelihood of successful plant establishment beyond current species' ranges under changing climate is complicated by the interaction of genetic and environmental controls on seedling establishment. To determine how genetics and climate may interact to affect seedling establishment, we transplanted recently germinated seedlings from high- and low-elevation provenances (HI and LO, respectively) of Pinus flexilis in common gardens arrayed along an elevation and canopy gradient from subalpine forest into the alpine zone and examined differences in physiology and morphology between provenances and among sites. Plant dry mass, projected leaf area and shoot:root ratios were 12-40% greater in LO compared with HI seedlings at each elevation. There were no significant changes in these variables among sites except for decreased dry mass of LO seedlings in the alpine site. Photosynthesis, carbon balance (photosynthesis/respiration) and conductance increased >2× with elevation for both provenances, and were 35-77% greater in LO seedlings compared with HI seedlings. There were no differences in dark-adapted chlorophyll fluorescence (Fv/Fm) among sites or between provenances. Our results suggest that for P. flexilis seedlings, provenances selected for above-ground growth may outperform those selected for stress resistance in the absence of harsh climatic conditions, even well above the species' range limits in the alpine zone. This indicates that forest genetics may be important to understanding and managing species' range adjustments due to climate change.

  6. Influence of plant-parasitic nematodes on longleaf pine seedlings.

    Science.gov (United States)

    Ruehle, J L

    1973-01-01

    Seedlings of longleaf pine (Pinus palustris) were grown in 20-cm pots for 5 to 7 months in the greenhouse following inoculation with a high or low level of one of seven species of plant-parasitic nematodes. Belonolaimus longicaudatus and Helicotylenchus dihystera had no effect on seedling growth. High inoculum densities of Hoplolaimus galeatus and Tylenchorhynchus claytoni caused a significant reduction of fresh weight of seedling roots. Root and top weights of seedlings grown in soil infested with Meloidodera floridensis or Pratylenchus brachyurus were significantly less than those of seedlings in noninfested soil. Root growth of seedlings was stimulated by the higher inoculum density of Scutellonema brachyurum.

  7. Variation Analysis of Seed and Seedling Traits of Cross Combination Progenies in Populus

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Twenty-five species and hybrids in Populus were used as parents, and 26 cross combinations, including more than 5 000 seedlings, were obtained by artificial cross breeding. The length of infructescence, number of seeds per infructescence, thousand-seed weight, germination rate of seeds among these cross combinations were tested. The results indicated that the cross combinational effects were significant for these traits, and demonstrated that the length of infructescence, thousand-seed weight were positively affected by female parent. In addition, seedling height, diameter above ground, diameter at breast height (DBH) of 17 cross combination progenies were investigated. The analysis of mean and standard deviation of these three traits showed that seedling height, diameter above ground, DBH had extensive variation among combinations and individuals within combination. Variance analysis and estimate of heritability indicated that the three traits had wide variation and were controlled by heredity. It was feasible to select superior cross combinations and seedlings. Further more, the result of multiple comparison showed that P. deltoides 'Lux' × P. deltoides 'D324', P. ussuriensis cl. 'U4' × P. deltoides 'T66', P. ussuriensis cl. 'U4' × P. deltoides 'T26', P. deltoides 'Lux' × P. ussuriensis cl. 'U3', (P. tomentosa × P. bolleana) × (P. alba × P. glandulosa), (P. alba × P. tomentosa) × (P. alba × P. glandulosa ), and (P. alba × P. glandulosa 'No. 2') × P. tomentosa 'Lumao 50' were superior cross combinations with higher growth rate. Finally, 123 elite seedlings were selected for further test.

  8. Germination and Seedling Development of Seeds from Different Parkia biglobosa (Jacq G. Don Trees

    Directory of Open Access Journals (Sweden)

    Christiana O. ADEYEMI

    2013-02-01

    Full Text Available The effect of daylight, continuous illumination and acid scarification on the seed germination and seedling vegetative growth (epicotyl and hypocotyl lengths, and number of secondary roots of different Parkia biglobosawere investigated in the Plant Physiology Laboratory University of Ilorin, Ilorin Kwara State Nigeria. Seeds from two out of the twenty six Parkia tree samples (trees B and T germinated within 24 hours of planting in the daylight germination study while seeds from another tree (Q did not germinate until the third week after planting (3WAP. Some seeds have higher germination percentage both in the daylight (preliminary germination study and in the continuous light (illuminated study. The treatment with concentrated Sulphric acid (conc. H2SO4was effective in breaking the seed dormancy as seeds from eight (8 trees produced one hundred percent (100% germination. At p= 0.05 the length of epicotyl and hypocoty1 lengths were significantly different as seedling vegetative growth were long in the seedlings from the daylight experiment than the continuous light experiment. The vegetative growths of the seedlings from the scarified seed were longer at 15min of scarification in all except in trees F and Z. It was observed that the time of scarification affect the both seed germination and seedling development.

  9. Growth of Scots Pine and Silver Birch Seedlings on Different Nursery Container Media

    Directory of Open Access Journals (Sweden)

    Fahrettin TILKI

    2014-12-01

    Full Text Available Peat has been the most common growing medium in tree nurseries, either alone or as a component of growing media mixes. However, as a result of increasing costs and decreasing amount of peat, seedling-growers are seeking more local growing medium components. In this study, container seedlings of Scots pine (Pinus sylvestris L. and silver birch (Betula pendula Roth were grown in pure peat and peat mixtures containing perlite and zeolite.  Physical parameters (height, shoot diameter, root dry weight, shoot dry weight, total dry weight were measured along with several morphological parameters (sturdiness quotient, height/diameter, shoot/root ratio. The zeolite additive in peat changed some media properties, and significant relation was established between some morphological attributes of seedlings and some medium properties in both species. On average, the seedlings grew best in pure peat, but zeolite additions to peat did not affect some morphological parameters negatively. The results suggest that zeolite has potential to be used as a component of peat based growing medium mixtures, and addition of zeolite to peat container medium in proportions of 10% by volume in Scots pine and up to 20% in silver birch was shown to be a feasible material for growing Scots pine and silver birch seedlings.

  10. Effect of seed mass on emergence and seedling development in Ptero-carpus marsupium Roxb

    Institute of Scientific and Technical Information of China (English)

    Yogeshwar Mishra; Rimi Rawat; P.K.Rana; M.K.Sonkar; Naseer Mohammad

    2014-01-01

    We investigated the effect of seed mass on emergence, seed-ling survival and growth of Pterocarpus marsupium Roxb., a medium to large, commercially valuable and deciduous tree species. Among the three size classes viz. small (10-12 mm), medium (13-15 mm) and large (16-17 mm), the maximum proportion of seed by number (54.12%) and dry weight (51.87%) was recorded in the medium size seed class. Seed length and seed width were greatest in the large seed class (16.50 mm, 7.33 mm) followed by medium (13.50 mm, 5.60 mm) and small (11.37 mm, 3.66 mm). Similarly, hundred seed weight (100 sw) varied from a maximum of 12.92 g in the large seed class to intermediate 10.95 g in the medium seed class and minimum of 7.02 g in the small seed class. The large seed size showed maximum emergence and shoot length over the medium and small seed class. After six months of growth, significant variations due to seed size were also observed for the growth and dry weight of P. marsupium seedlings. Seedling vigour, expressed in terms of height, collar diameter, number of leaves and dry biomass, was sig-nificantly affected by seed class. Seedlings that emerged from large seeds showed better growth and produced heavier seedlings as compared to medium and small seeds.

  11. Effect of a longitudinally applied voltage upon the growth of Zea mays seedlings

    Science.gov (United States)

    Desrosiers, M. F.; Bandurski, R. S.

    1988-01-01

    The electrical parameters that affect young seedling growth were investigated. Voltages ranging from 5 to 40 volts were applied longitudinally along the mesocotyl region of 4-day old Zea mays L. (cv Silver Queen) seedlings for periods of 3 or 4 hours. It was determined that: (a) making the tips of the seedlings electrically positive relative to the base strongly inhibited shoot growth at 5 volts, whereas the reverse polarity had no effect; (b) at higher voltages, making the tip of the seedlings negative caused less growth inhibition than the reverse polarity at each voltage level; (c) the higher the applied voltage the greater the degree of inhibition; and, (d) the more growth inhibition experienced by the plants the poorer, and slower, their recovery. Previous observations of a relationship between the amount of free indole-3-acetic acid in the mesocotyl cortex and the growth rate of the mesocotyl and of gravitropism-induced movement of labeled indole-3-acetic acid from the seed to the shoot lead to the prediction of a voltage-dependent gating of the movement of indole-3-acetic acid from the stele to the cortex. This provided the basis for attempting to alter the growth rate of seedlings by means of an applied voltage.

  12. Combined effects of lead and acid rain on photosynthesis in soybean seedlings.

    Science.gov (United States)

    Hu, Huiqing; Wang, Lihong; Liao, Chenyu; Fan, Caixia; Zhou, Qing; Huang, Xiaohua

    2014-10-01

    To explore how lead (Pb) and acid rain simultaneously affect plants, the combined effects of Pb and acid rain on the chlorophyll content, chlorophyll fluorescence reaction, Hill reaction rate, and Mg(2+)-ATPase activity in soybean seedlings were investigated. The results indicated that, when soybean seedlings were treated with Pb or acid rain alone, the chlorophyll content, Hill reaction rate, Mg(2+)-ATPase activity, and maximal photochemical efficiency (F(v)/F(m)) were decreased, while the initial fluorescence (F 0) and maximum quantum yield (Y) were increased, compared with those of the control. The combined treatment with Pb and acid rain decreased the chlorophyll content, Hill reaction rate, Mg(2+)-ATPase activity, F(v)/F(m), and Y and increased F 0 in soybean seedlings. Under the combined treatment with Pb and acid rain, the two factors showed additive effects on the chlorophyll content in soybean seedlings and exhibited antagonistic effects on the Hill reaction rate. Under the combined treatment with high-concentration Pb and acid rain, the two factors exhibited synergistic effects on the Mg(2+)-ATPase activity, F 0, F v/F m, as well as Y. In summary, the inhibition of the photosynthetic process is an important physiological basis for the simultaneous actions of Pb and acid rain in soybean seedlings.

  13. Relationships between xanthoxin, phototropism, and elongation growth in the sunflower seedling Helianthus annuus L.

    Science.gov (United States)

    Franssen, J M; Bruinsma, J

    1981-04-01

    For phototropic curvature of a green sunflower seedling, only the hypocotyl has to be illuminated; the tip and cotyledons are not involved in stimulus perception. The etiolated seedling is phototropically insensitive, illumination of only the hypocotyl renders it sensitive. It is concluded that the photoreceptor is located within the responding organ. In curving seedlings, the endogenous indoleacetic acid (IAA) remains evenly distributed. However, the inhibitor, xanthoxin (Xa), accumulates on the illuminated side. The degree of phototropic response is generally related to the concentration of Xa. The amount of phototropic curvature is independent of the rate of elongation growth, the former can be changed without affecting the latter, and vice versa. The data conflict with the Cholodny-Went theory, whereas they support the hypothesis of Blaauw that the phototropic reaction is caused by the local accumulation of a growth-inhibiting substance on the irradiated side.

  14. Effect of saline water irrigation on seed germination and early seedling growth of the halophyte quinoa

    DEFF Research Database (Denmark)

    Panuccio, M.R.; Jacobsen, Sven-Erik; Saleem Akhtar, Saqib;

    2014-01-01

    been carried out to investigate the mechanisms used by quinoa, a facultative halophytic species, in order to cope with high salt levels at various stages of its develop- ment. Quinoa is regarded as one of the crops that might sustain food security in this century, grown primarily for its edible seeds...... of SW and different salts on seed germination, seedling emergence and the antioxidative pathway of quinoa. Seeds were germi- nated in Petri dishes and seedlings grown in pots with SW solutions (25, 50, 75 and 100 %) and NaCl, CaCl2, KCl and MgCl2 individually, at the concentrations in which...... parameters affected were root and shoot length, root morphology, fresh and dry weight, and water content. An efficient antioxidant mechanism was present in quinoa, activated by salts during germination and early seedling growth, as shown by the activities of antioxidant enzymes. Total antioxidant capacity...

  15. GROWTH AND NODULATION OF LEUCAENA AND PROSOPIS SEEDLINGS IN SOIL PLUS TANNERY SLUDGE

    Directory of Open Access Journals (Sweden)

    Ademir Sérgio Ferreira de Araújo

    2006-01-01

    Full Text Available The objective of this paper was to evaluate the growth and nodulation of Leucaena and Prosopis seedlings in soil plus tannery sludge. The study was conducted in a greenhouse, using bags containing soil plus tannery sludge. Seedlings of Leucaena and Prosopis inoculated with Bradyrhizobium sp were used. Results were evaluated 90 days after plant emergency. The application of tannery sludge, in the rate of 11.250 kg per hectare significantly increased plant height, stem diameter, and above ground dry mass ofLeucaena. Regarding Prosopis, there were no significant increases in these variables with tannery sludge application, except for aerial dry mass. No significant differences were seen between the treatments with sludge and inoculated with Bradyrhizobium sp. as to nodule number and dry mass. Tannery sludge evaluated in this work did not affect nodulation, besides favoring Leucaena and Prosopis seedling growth.

  16. Adult trees cause density-dependent mortality in conspecific seedlings by regulating the frequency of pathogenic soil fungi.

    Science.gov (United States)

    Liang, Minxia; Liu, Xubing; Gilbert, Gregory S; Zheng, Yi; Luo, Shan; Huang, Fengmin; Yu, Shixiao

    2016-12-01

    Negative density-dependent seedling mortality has been widely detected in tropical, subtropical and temperate forests, with soil pathogens as a major driver. Here we investigated how host density affects the composition of soil pathogen communities and consequently influences the strength of plant-soil feedbacks. In field censuses of six 1-ha permanent plots, we found that survival was much lower for newly germinated seedlings that were surrounded by more conspecific adults. The relative abundance of pathogenic fungi in soil increased with increasing conspecific tree density for five of nine tree species; more soil pathogens accumulated around roots where adult tree density was higher, and this greater pathogen frequency was associated with lower seedling survival. Our findings show how tree density influences populations of soil pathogens, which creates plant-soil feedbacks that contribute to community-level and population-level compensatory trends in seedling survival.

  17. The effects of heat treatment on technological properties in Red-bud maple (Acer trautvetteri Medw.) wood.

    Science.gov (United States)

    Korkut, Süleyman; Kök, M Samil; Korkut, Derya Sevim; Gürleyen, Tuğba

    2008-04-01

    Heat treatment is often used to improve the dimensional stability of wood. In this study, the effects of heat treatment on technological properties of Red-bud maple (Acer trautvetteri Medw.) wood were examined. Samples obtained from Düzce Forest Enterprises, Turkey, were subjected to heat treatment at varying temperatures (120 degrees C, 150 degrees C and 180 degrees C) and for varying durations (2h, 6h and 10h). The technological properties of heat-treated wood samples and control samples were tested. Compression strength parallel to grain, bending strength, modulus of elasticity in bending, janka-hardness, impact bending strength, and tension strength perpendicular to grain were determined. The results showed that technological strength values decreased with increasing treatment temperature and treatment times. Red-bud maple wood could be utilized by using proper heat treatment techniques with minimal losses in strength values in areas where working, and stability such as in window frames, are important factors.

  18. Numerical Solution and Simulation of Second-Order Parabolic PDEs with Sinc-Galerkin Method Using Maple

    Directory of Open Access Journals (Sweden)

    Aydin Secer

    2013-01-01

    Full Text Available An efficient solution algorithm for sinc-Galerkin method has been presented for obtaining numerical solution of PDEs with Dirichlet-type boundary conditions by using Maple Computer Algebra System. The method is based on Whittaker cardinal function and uses approximating basis functions and their appropriate derivatives. In this work, PDEs have been converted to algebraic equation systems with new accurate explicit approximations of inner products without the need to calculate any numeric integrals. The solution of this system of algebraic equations has been reduced to the solution of a matrix equation system via Maple. The accuracy of the solutions has been compared with the exact solutions of the test problem. Computational results indicate that the technique presented in this study is valid for linear partial differential equations with various types of boundary conditions.

  19. When Does Choice of Downscaling Method Matter in Decision Making? A Case Study with Maple Syrup Production

    Science.gov (United States)

    Bryan, A. M.; Kearney, E.; Rapp, J. M.; Karmalkar, A.; Morelli, T. L.

    2016-12-01

    When planning and preparing for climate change, practitioners rely on climate models to help them make informed decisions. All climate change model data ultimately derive from global-scale models, which are typically too coarse for local-scale decision making; thus, these models are often "downscaled" in order to resolve finer details within the decision space. A few downscaling approaches exist, each with a unique set of strengths and limitations, yet their implications on any particular decision are not always clear to decision makers. Using maple syrup production as a case study, we demonstrate a possible method of evaluating the sensitivity of a specific decision to downscaling method selection. We compare two downscaling techniques (dynamical and statistical) and two training methods within the statistical downscaling approach (bias-corrected spatial disaggregation, or BCSD, and bias corrected constructed analogs, or BCCA) with respect to their ability to capture daily freeze- thaw cycles, the driver of sapflow in maple syrup production. For each downscaling approach, we evaluate simulations of historical freeze-thaw patterns using gridded temperature observations, and compare projected changes in freeze-thaw patterns by mid-century. We discuss the implications of our results on the decision of "when to tap" faced by maple syrup producers, as well as similar decisions in other industries. Our results reveal which downscaling technique(s) is (are) best suited for helping maple syrup producers make plans toward adapting their tapping practices for climate change. In addition, our results provide producers with a plausible range of optimal tapping dates by mid-century, based on the most skilled downscaling approach. Finally, we highlight insights relevant to the climate modeling community, and lessons learned toward making climate science actionable.

  20. MaPLE: A MapReduce Pipeline for Lattice-based Evaluation and Its Application to SNOMED CT.

    Science.gov (United States)

    Zhang, Guo-Qiang; Zhu, Wei; Sun, Mengmeng; Tao, Shiqiang; Bodenreider, Olivier; Cui, Licong

    2014-10-01

    Non-lattice fragments are often indicative of structural anomalies in ontological systems and, as such, represent possible areas of focus for subsequent quality assurance work. However, extracting the non-lattice fragments in large ontological systems is computationally expensive if not prohibitive, using a traditional sequential approach. In this paper we present a general MapReduce pipeline, called MaPLE (MapReduce Pipeline for Lattice-based Evaluation), for extracting non-lattice fragments in large partially ordered sets and demonstrate its applicability in ontology quality assurance. Using MaPLE in a 30-node Hadoop local cloud, we systematically extracted non-lattice fragments in 8 SNOMED CT versions from 2009 to 2014 (each containing over 300k concepts), with an average total computing time of less than 3 hours per version. With dramatically reduced time, MaPLE makes it feasible not only to perform exhaustive structural analysis of large ontological hierarchies, but also to systematically track structural changes between versions. Our change analysis showed that the average change rates on the non-lattice pairs are up to 38.6 times higher than the change rates of the background structure (concept nodes). This demonstrates that fragments around non-lattice pairs exhibit significantly higher rates of change in the process of ontological evolution.

  1. Finding higher symmetries of differential equations using the MAPLE package DESOLVII

    Science.gov (United States)

    Vu, K. T.; Jefferson, G. F.; Carminati, J.

    2012-04-01

    We present and describe, with illustrative examples, the MAPLE computer algebra package DESOLVII, which is a major upgrade of DESOLV. DESOLVII now includes new routines allowing the determination of higher symmetries (contact and Lie-Bäcklund) for systems of both ordinary and partial differential equations. Catalogue identifier: ADYZ_v2_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADYZ_v2_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 10 858 No. of bytes in distributed program, including test data, etc.: 112 515 Distribution format: tar.gz Programming language: MAPLE internal language Computer: PCs and workstations Operating system: Linux, Windows XP and Windows 7 RAM: Depends on the type of problem and the complexity of the system (small ≈ MB, large ≈ GB) Classification: 4.3, 5 Catalogue identifier of previous version: ADYZ_v1_0 Journal reference of previous version: Comput. Phys. Comm. 176 (2007) 682 Does the new version supersede the previous version?: Yes Nature of problem: There are a number of approaches one may use to find solutions to systems of differential equations. These include numerical, perturbative, and algebraic methods. Unfortunately, approximate or numerical solution methods may be inappropriate in many cases or even impossible due to the nature of the system and hence exact methods are important. In their own right, exact solutions are valuable not only as a yardstick for approximate/numerical solutions but also as a means of elucidating the physical meaning of fundamental quantities in systems. One particular method of finding special exact solutions is afforded by the work of Sophus Lie and the use of continuous transformation groups. The power of Lie's group theoretic method lies in its ability to unify a number of ad hoc

  2. Simulated drought influences oxidative stress in Zea mays seedlings ...

    African Journals Online (AJOL)

    Simulated drought influences oxidative stress in Zea mays seedlings. ... Bayero Journal of Pure and Applied Sciences. Journal Home · ABOUT ... Seedlings were grown for 8 weeks in nursery bags filled with sandy-loam soil in two categories.

  3. The fungi causin damping-off of carrot seedlings

    Directory of Open Access Journals (Sweden)

    Bogdan Nowicki

    2013-12-01

    Full Text Available When 136 samples of dying carrot seedlings from several fields were analyzed Alternaria rudicina proved to be the most common seedling pathogen (41%, followed by some Fusarium species (27%, mostly F. avenaceum.The less common seedling pathogens were Pythium spp. (13%, Phoma spp.(2,5% and Botrytis cinerea (1,4%. Some other fungi (Bipolaris sorokiniana, Sclerotinia sclerotiorum, Stemphylium botryosym and Ulocladium consortiale were found in less than 1% of seedlings examined.

  4. Growth and nutrient uptake of Citrus rootstock varieties as affected ...

    African Journals Online (AJOL)

    Growth and nutrient uptake of Citrus rootstock varieties as affected poultry manure and NPK fertilizer in Ibadan, Southwestern Nigeria. ... Since plant height and stem diameter determine the quality of rootstock seedlings, poultry manure at 9 ...

  5. Containers of Attalea funifera fibers to produce eucalyptus seedlings

    Directory of Open Access Journals (Sweden)

    Andrea Vita Reis Mendonça

    2016-09-01

    Full Text Available The aim of this study was to assess the technical feasibility of using biodegradable containers made of fiber waste of Attalea funifera Martius to produce seedling of Eucalyptus camaldulensis Dehnh. The work was carried out in three stages: manufacture of piassava fiber containers, seedling production and field simulation. The experiment of seedling production was in completely randomized design, with two treatments (polyethylene tube and biodegradable container and 10 repetitions, with 64 seedlings per repetition. After 93 days, seedlings were evaluated based on quality variables. The simuation of initial growth of seedlings in the field consisted in planting seedlings in containers of 11L, in completely randomized design, with three treatments: seedlings produced in polyethylene tubes; seedlings produced in biodegradable containers, without removal of the container during planting; and seedlings produced in biodegradable containers, with removal of the container at planting, with ten repetitions, with one seedling by repetition. The biodegradable container withstood the production cycle and resulted in seedlings within acceptable standards quality. The use of biodegradable container, made of palm fibers, waived the removal of this vessel in the final planting.

  6. Containers of Attalea funifera fibers to produce eucalyptus seedlings

    Directory of Open Access Journals (Sweden)

    Andrea Vita Reis Mendonça

    2016-09-01

    Full Text Available The aim of this study was to assess the technical feasibility of using biodegradable containers made of fiber waste of Attalea funifera Martius to produce seedling of Eucalyptus camaldulensis Dehnh. The work was carried out in three stages: manufacture of piassava fiber containers, seedling production and field simulation. The experiment of seedling production was in completely randomized design, with two treatments (polyethylene tube and biodegradable container and 10 repetitions, with 64 seedlings per repetition. After 93 days, seedlings were evaluated based on quality variables. The simuation of initial growth of seedlings in the field consisted in planting seedlings in containers of 11L, in completely randomized design, with three treatments: seedlings produced in polyethylene tubes; seedlings produced in biodegradable containers, without removal of the container during planting; and seedlings produced in biodegradable containers, with removal of the container at planting, with ten repetitions, with one seedling by repetition. The biodegradable container withstood the production cycle and resulted in seedlings within acceptable standards quality. The use of biodegradable container, made of palm fibers, waived the removal of this vessel in the final planting.

  7. [Influence of seedling assortment on Panax notoginseng growth and yield].

    Science.gov (United States)

    Cui, X; Wang, C; Chen, Z

    1998-02-01

    Making Panax notoginseng seedling assortment according to seedling size before transplanting, the result shows that the influence is better, the yield of root tuber and fruit is higher. Culturing good seedling is the fundamental measure to increase yield of P. notoginseng.

  8. Polyembryony and identification of Volkamerian lemon zygotic and nucellar seedlings using RAPD Poliembrionia e identificação de seedlings zigóticos e nucelares de limão volkameriano com RAPD

    Directory of Open Access Journals (Sweden)

    María Andrade-Rodríguez

    2004-06-01

    Full Text Available The objectives of this work were to evaluate the frequency of polyembryony, and to identify zygotic and nucellar seedlings of Citrus volkameriana using RAPD. Twenty-five polyembryonic and eight monoembryonic seeds were cultivated in vitrofor six months. DNA from seedlings was extracted and used in combination with five RAPD primers to identify zygotic or nucellar origin of the seedlings. Environmental conditions of the year affected significantly (POs objetivos deste trabalho foram avaliar a freqüência da poliembrionia e indentificar os seedlings zigóticos e nucelares de Citrus volkameriana usando RAPD. Cultivaram-se in vitro 25 sementes poliembriônicas e 8 monoembriônicas, por seis meses. Extraiu-se o DNA dos seedlings e usou-se em combinação com cinco primers RAPD para identificar a origem zigótica e nucelar das plântulas. Os resultados mostraram que as condições ambientais do ano afetaram significativamente (P<0,05 as características morfológicas dos frutos e o número de embriões por semente. Os índices de sementes poliembriônicas variaram nos três anos de avaliação (30,9%, 44,8% e 54,4%. As características morfológicas não se correlacionaram com a poliembrionia. A cultura in vitro possibilita que todos os embriões de cada semente cresçam, favorecendo os seedlings identificados como zigóticos. Nas sementes poliembriônicas e monoembriônicas, 25,9% e 87,5% dos seedlings, respectivamente, originaram-se sexualmente. Nem todos os seedlings zigóticos foram produzidos por embriões localizados no micrófilo das sementes poliembriônicas.

  9. Foliar δ15N is affected by foliar nitrogen uptake, soil nitrogen, and mycorrhizae along a nitrogen deposition gradient.

    Science.gov (United States)

    Vallano, Dena M; Sparks, Jed P

    2013-05-01

    Foliar nitrogen isotope (δ(15)N) composition patterns have been linked to soil N, mycorrhizal fractionation, and within-plant fractionations. However, few studies have examined the potential importance of the direct foliar uptake of gaseous reactive N on foliar δ(15)N. Using an experimental set-up in which the rate of mycorrhizal infection was reduced using a fungicide, we examined the influence of mycorrhizae on foliar δ(15)N in potted red maple (Acer rubrum) seedlings along a regional N deposition gradient in New York State. Mycorrhizal associations altered foliar δ(15)N values in red maple seedlings from 0.06 to 0.74 ‰ across sites. At the same sites, we explored the predictive roles of direct foliar N uptake, soil δ(15)N, and mycorrhizae on foliar δ(15)N in adult stands of A. rubrum, American beech (Fagus grandifolia), black birch (Betula lenta), and red oak (Quercus rubra). Multiple regression analysis indicated that ambient atmospheric nitrogen dioxide (NO2) concentration explained 0, 69, 23, and 45 % of the variation in foliar δ(15)N in American beech, red maple, red oak, and black birch, respectively, after accounting for the influence of soil δ(15)N. There was no correlation between foliar δ(13)C and foliar %N with increasing atmospheric NO2 concentration in most species. Our findings suggest that total canopy uptake, and likely direct foliar N uptake, of pollution-derived atmospheric N deposition may significantly impact foliar δ(15)N in several dominant species occurring in temperate forest ecosystems.

  10. Third year effects of cloudwater and ozone on red spruce seedlings

    Energy Technology Data Exchange (ETDEWEB)

    Pier, P.A.; Thornton, F.C.; McDuffie, C. Jr. (Tennessee Valley Authority, Muscle Shoals, AL (United States))

    1991-05-01

    The reduction in growth of high elevation red spruce in the eastern US has been attributed in part to greater exposure to atmospheric pollution which occurs at high elevation. The authors objective was to evaluate the impact of ambient ozone and cloudwater deposition on the growth of red spruce seedlings at a high elevation site. Potted native and Phyton-grown (Phyton Technologies) red spruce seedlings were exposed in open-top field chambers at Whitetop Mountain, Virginia (elevation 1,680) for the third season to treatments of: (1) exclusion of clouds and 50% reduction in ambient O{sub 3} (COE), (2) O{sub 3} with clouds excluded (CO), (3) exposure to clouds and O{sub 3}, as control chambers (CC), and (4) open plots (AA). Plant biomass components and diameter increment growth for both seedling types were not affected by treatments. Photosynthesis was not enhanced by removal of cloudwater and O{sub 3}. Respiration (R{sub d}) generally was not affected by treatments; however, R{sub d} in native seedling needles of previous year and two-year previous growth was significantly greater in CC than CO and COE on several sampling dates, indicating that cloudwater and O{sub 3} may be causing higher R{sub d}.

  11. The APX4 locus regulates seed vigor and seedling growth in Arabidopsis thaliana.

    Science.gov (United States)

    Wang, Ya-Ying; Hecker, Amanda G; Hauser, Bernard A

    2014-04-01

    The amino acid sequence of APX4 is similar to other ascorbate peroxidases (APXs), a group of proteins that protect plants from oxidative damage by transferring electrons from ascorbate to detoxify peroxides. In this study, we characterized two apx4 mutant alleles. Translational fusions with GFP indicated APX4 localizes to chloroplasts. Both apx4 mutant alleles formed chlorotic cotyledons with significantly reduced chlorophyll a, chlorophyll b and lutein. Given the homology of APX to ROS-scavenging proteins, this result is consistent with APX4 protecting seedling photosystems from oxidation. The growth of apx4 seedlings was stunted early in seedling development. In addition, APX4 altered seed quality by affecting seed coat formation. While apx4 seed development appeared normal, the seed coat was darker and more permeable than the wild type. In addition, accelerated aging tests showed that apx4 seeds were more sensitive to environmental stress than the wild-type seeds. If APX4 affects seed pigment biosynthesis or reduction, the seed coat color and permeability phenotypes are explained. apx4 mutants had cotyledon chlorosis, increased H₂O₂ accumulation, and reduced soluble APX activity in seedlings. These results indicate that APX4 is involved in the ROS-scavenging process in chloroplasts.

  12. Development of cork oak (Quercus suber L.) seedlings in response to tree shelters and mulching in northwestern Tunisia

    Institute of Scientific and Technical Information of China (English)

    Taher Mechergui; Marta Pardos; Naceur Boussaidi; Brahim Hasnaoui; Douglass F.Jacobs

    2013-01-01

    The need for reforestation in cork oak (Quercus suber L.)areas is challenged by difficulties.Principal among these is herbivory of young plants,vegetative competition,and slow growth rates of cork oak seedlings.We evaluated the early development of cork oak seedlings treated using tree shelters and mulching in northwestern Tunisia.We tested three tree shelter treatments (non-vented,vented,and control) to shield seedlings from animal damage and five mulch types to control competing vegetation (Italian Stone Pine,Lentisk,combination of Italian Stone Pine and Lentisk (organic mulches),gravel (inorganic mulch) and no mulch).At the end of the two-year experiment,sheltered seedlings were 89-99% taller than unsheltered seedlings and had higher numbers and lengths of shoot growth flushes.In contrast,both stem diameter growth and dry weight biomass (from samples extracted after two years)were significantly reduced inside tree shelters.Root-to-shoot ratio was not significantly different in sheltered vs.unsheltered seedlings,suggesting that tree shelters do not adversely affect this parameter.Mulching alone did not favour growth,but could be beneficial when combined with tree shelters.The combination of vented tree shelters and gravel mulch was the most effective treatment for promoting diameter,height and stem volume growth.

  13. Seed size variation in the palm Euterpe edulis and the effects of seed predators on germination and seedling survival

    Science.gov (United States)

    Pizo, Marco A.; Von Allmen, Christiane; Morellato, L. Patricia C.

    2006-05-01

    Intraspecific variation in seed size is common in wild plant populations and has important consequences for the reproductive success of individual plants. Multiple, often conflicting evolutionary forces mediated by biotic as well as abiotic agents may maintain such a variation. In this paper we assessed seed size variation in a population of the threatened, commercially important palm Euterpe edulis in southeast Brazil. We investigated (i) how this variation affects the probability of attack by vertebrate and invertebrate post-dispersal seed predators, and (ii) if seed size influences the outcome of seeds damaged by beetles in terms of seed germination and early survival of seedlings. Euterpe edulis seeds varied in diameter from 8.3 to 14.1 mm. Neither insects nor rodents selected the seeds they preyed upon based on seed size. Seed germination and total, shoot and root biomasses of one-year seedlings were significantly and positively affected by seed size. Root biomass and seedling survival were negatively affected by seed damage caused by a scolytid beetle ( Coccotrypes palmarum) whose adults bore into seeds to consume part of the endosperm, but do not oviposit on them. Seed size had a marginally significant effect on seedling survival. Therefore, if any advantage is accrued by E. edulis individuals producing large seeds, this is because of greater seed germination success and seedling vigor. If this is so, even a relatively narrow range of variation in seed size as observed in the E. edulis population studied may translate into differential success of individual plants.

  14. Do mycorrhizal network benefits to survival and growth of interior Douglas-fir seedlings increase with soil moisture stress?

    Science.gov (United States)

    Bingham, Marcus A; Simard, Suzanne W

    2011-11-01

    Facilitation of tree establishment by ectomycorrhizal (EM) networks (MNs) may become increasingly important as drought stress increases with climate change in some forested regions of North America. The objective of this study was to determine (1) whether temperature, CO(2) concentration ([CO(2)]), soil moisture, and MNs interact to affect plant establishment success, such that MNs facilitate establishment when plants are the most water stressed, and (2) whether transfer of C and water between plants through MNs plays a role in this. We established interior Douglas-fir (Pseudotsuga menziesiivar.glauca) seedlings in root boxes with and without the potential to form MNs with nearby conspecific seedlings that had consistent access to water via their taproots. We varied temperature, [CO(2)], and soil moisture in growth chambers. Douglas-fir seedling survival increased when the potential existed to form an MN. Growth increased with MN potential under the driest soil conditions, but decreased with temperature at 800 ppm [CO(2)]. Transfer of (13)C to receiver seedlings was unaffected by potential to form an MN with donor seedlings, but deuterated water (D(2)O) transfer increased with MN potential under ambient [CO(2)]. Chlorophyll fluorescence was reduced when seedlings had the potential to form an MN under high [CO(2)] and cool temperatures. We conclude that Douglas-fir seedling establishment in laboratory conditions is facilitated by MN potential where Douglas-fir seedlings have consistent access to water. Moreover, this facilitation appears to increase as water stress potential increases and water transfer via networks may play a role in this. These results suggest that conservation of MN potential may be important to forest regeneration where drought stress increases with climate change.

  15. Effect of benfluralin on Pinus pinea seedlings mycorrhized with Pisolithus tinctorius and Suillus bellinii--study of plant antioxidant response.

    Science.gov (United States)

    Franco, Albina R; Pereira, Sofia I A; Castro, Paula M L

    2015-02-01

    In this study, Pinus pinea seedlings mycorrhized with selected ectomycorrhizal fungi (ECMF), Pisolithus tinctorius and Suillus bellinii, were exposed to the herbicide benfluralin. Non-mycorrhized P. pinea seedlings and seedlings mycorrhized with ECMF were transferred to benfluralin-spiked soils at levels of 0.165, 1.65 and 16.5 mg kg(-1). Plant growth and the fungal role on plant antioxidant response were assessed. In the presence of benfluralin, higher plant growth was observed in mycorrhized plants compared to non-mycorrhized plants, but ECMF colonisation and nutrient uptake were affected by the herbicide. Benfluralin showed no effect on lipid peroxidation in P. pinea seedlings. However, seedlings mycorrhized with S. bellinii showed higher levels of lipid peroxidation when compared to non-mycorrhized ones, both in the presence and absence of benfluralin. The increase of lipid peroxidation could be related to seedling growth induced by the fungus and not to benfluralin toxicity. A similar trend was observed in seedlings mycorrhized with P. tinctorius when exposed to higher benfluralin concentrations, suggesting that the antioxidant response to benfluralin is related not only to fungus species, but also to the level of stress applied in the soil. The higher amount of superoxide dismutase activity in P. pinea seedlings tissues exposed to benfluralin could indicate a plant adaptative response to benfluralin toxicity. Catalase activity showed no increase with benfluralin exposure. Pre-established P. tinctorius mycorrhization conferred root protection and enhanced plant growth in benfluralin spiked soil, inferring that P. tinctorius - P. pinea association could advantageous for plant growth in soils contaminated with pesticides.

  16. Roseomonas aceris sp. nov. isolated from a mono maple tree in the Shirakami Mountains in Japan.

    Science.gov (United States)

    Tonouchi, Akio; Tazawa, Daisuke

    2014-01-01

    A novel bacterial strain belonging to the genus Roseomonas was isolated from the trunk surface of a mono maple (Acer mono) tree growing in the Shirakami Mountains. The strain, designated R-1(T), was Gram-negative, non-motile, and oval-rod, and formed reddish colonies on agar plates, as has previously been described for Roseomonas species. Although motility was not observed, cells were peritrichously flagellated. Strain R-1(T) preferred organic acids over carbohydrates as growth substrates. The major cellular fatty acid was C₁₈:₁ ω7c (48.79%). Ubiquinone-10 was the major respiratory quinone. Strain R-1(T) demonstrated the highest 16S rRNA gene sequence similarity with Roseomonas pecuniae N75(T) (96.9%). Phylogenetic analysis based on 16S rRNA gene sequences confirmed that strain R-1(T) was a member of the genus Roseomonas and formed a cluster with R. pecuniae N75(T). DNA-DNA hybridization between strain R-1(T) and R. pecuniae N75(T) yielded 21.7% relatedness. On the basis of its phenotypic, phylogenetic, and chemotaxonomic char-acteristics, strain R-1(T) represents a novel species within the genus Roseomonas, for which the name Roseomonas aceris sp. nov. has been proposed. The type strain is R-1(T) (NBRC 109410(T) = DSM 26554 (T)).

  17. MAPLE Fabricated Fe3O4@Cinnamomum verum Antimicrobial Surfaces for Improved Gastrostomy Tubes

    Directory of Open Access Journals (Sweden)

    Alina Georgiana Anghel

    2014-06-01

    Full Text Available Cinnamomum verum-functionalized Fe3O4 nanoparticles of 9.4 nm in size were laser transferred by matrix assisted pulsed laser evaporation (MAPLE technique onto gastrostomy tubes (G-tubes for antibacterial activity evaluation toward Gram positive and Gram negative microbial colonization. X-ray diffraction analysis of the nanoparticle powder showed a polycrystalline magnetite structure, whereas infrared mapping confirmed the integrity of C. verum (CV functional groups after the laser transfer. The specific topography of the deposited films involved a uniform thin coating together with several aggregates of bio-functionalized magnetite particles covering the G-tubes. Cytotoxicity assays showed an increase of the G-tube surface biocompatibility after Fe3O4@CV treatment, allowing a normal development of endothelial cells up to five days of incubation. Microbiological assays on nanoparticle-modified G-tube surfaces have proved an improvement of anti-adherent properties, significantly reducing both Gram negative and Gram positive bacteria colonization.

  18. Phylogenetic test of speciation by host shift in leaf cone moths (Caloptilia) feeding on maples (Acer).

    Science.gov (United States)

    Nakadai, Ryosuke; Kawakita, Atsushi

    2016-07-01

    The traditional explanation for the exceptional diversity of herbivorous insects emphasizes host shift as the major driver of speciation. However, phylogenetic studies have often demonstrated widespread host plant conservatism by insect herbivores, calling into question the prevalence of speciation by host shift to distantly related plants. A limitation of previous phylogenetic studies is that host plants were defined at the family or genus level; thus, it was unclear whether host shifts predominate at a finer taxonomic scale. The lack of a statistical approach to test the hypothesis of host-shift-driven speciation also hindered studies at the species level. Here, we analyze the radiation of leaf cone moths (Caloptilia) associated with maples (Acer) using a newly developed, phylogeny-based method that tests the role of host shift in speciation. This method has the advantage of not requiring complete taxon sampling from an entire radiation. Based on 254 host plant records for 14 Caloptilia species collected at 73 sites in Japan, we show that major dietary changes are more concentrated toward the root of the phylogeny, with host shift playing a minor role in recent speciation. We suggest that there may be other roles for host shift in promoting herbivorous insect diversification rather than facilitating speciation per se.

  19. Maple syrup urine disease in Brazil: a panorama of the last two decades

    Directory of Open Access Journals (Sweden)

    Silvani Herber

    2015-06-01

    Full Text Available OBJECTIVE: To characterize a sample of Brazilian patients with maple syrup urine disease (MSUD diagnosed between 1992 and 2011. METHODS: In this retrospective study, patients were identified through a national reference laboratory for the diagnosis of MSUD and through contact with other medical genetics services across Brazil. Data were collected by means of a chart review. RESULTS: Eighty-three patients from 75 families were enrolled in the study (median age, 3 years; interquartile range [IQR], 0.57-7. Median age at onset of symptoms was 10 days (IQR 5-30, whereas median age at diagnosis was 60 days (IQR 29-240, p = 0.001. Only three (3.6% patients were diagnosed before the onset of clinical manifestations. A comparison between patients with (n = 12 and without (n = 71 an early diagnosis shows that early diagnosis is associated with the presence of positive family history and decreased prevalence of clinical manifestations at the time of diagnosis, but not with a better outcome. Overall, 98.8% of patients have some psychomotor or neurodevelopmental delay. CONCLUSION: In Brazil, patients with MSUD are usually diagnosed late and exhibit neurological involvement and poor survival even with early diagnosis. We suggest that specific public policies for diagnosis and treatment of MSUD should be developed and implemented in the country.

  20. [Allelopathy of different plants on wheat, cucumber and radish seedlings].

    Science.gov (United States)

    Shen, Huimin; Guo, Hongru; Huang, Gaobao

    2005-04-01

    By means of bioassay in laboratory and field, this paper studied the allelopathy of 18 kinds of plants in Gansu Province on the seedlings of wheat, cucumber and radish. The results showed that the aqueous extract of the stems and leaves of Artemisia annua, Solanum nigrum and Datura stramonium had the strongest allelopathy on test receptor plants, and their synthetic inhibitory effect (SE) was 47.66%, 32.89% and 26.63%, respectively. The SE of Xanthium sibiricum, Portulaca oleraca, Cephalanoplos segetum, and Chenopodium album was 21.71%, 20.93%, 20.83% and 20.2%, respectively, while Vicia amoena (SE 3.5%), Setaria viridis (SE 2.2%), and Cymamchum chinense (SE 1.97%) had a weaker allelopathy. Chenopodium ambrosioides (SE - 1.03%), Polygonum caespitosum (SE - 1.63%) and Avena fatua (SE 5.33%) had no evident allelopathy, but Artemisia annua affected the seedling height and fresh weight of radish, cucumber, wheat and maize, with the SE being 54.07%, 38.46%, 33.35% and 20.88%, respectively. Artemisia annua had a 44.70% of SE on wheat growth, and thus, had a certain value to develop and use.

  1. Arsenic toxicity in soybean seedlings and their attenuation mechanisms.

    Science.gov (United States)

    Armendariz, Ana L; Talano, Melina A; Travaglia, Claudia; Reinoso, Herminda; Wevar Oller, Ana L; Agostini, Elizabeth

    2016-01-01

    Even though vast areas contaminated with arsenic (As) are under soybean (Glycine max) cultivation, little is known about the growth and intrinsic antioxidant metabolism of soybean in response to As exposure. Thus, an evaluation was carried out of plant growth, root anatomy, antioxidant system and photosynthetic pigment content under arsenate (As(V)) and arsenite (As(III)) treatment. Soybean seedling growth was significantly affected at 25 μM or higher concentrations of As(V) or As(III), and the toxic effect on root growth was associated with cell death of root tips. Microscopic analysis of cross-sections of As-treated root showed a reduction in the cortex area, dark deposits in cortex cells and broken cells in the outer layer. Similarly, in the vascular cylinder, dark deposits within xylem vessel elements and phloem cell walls were observed. In all the analyzed parameters, the deleterious effect was more evident under As(III) than As(V) treatment. Arsenic-treated soybean seedlings showed increased activity of antioxidant enzymes [total peroxidases (Px) and superoxide dismutase (SOD)] in root and shoot harvested after 2 and 5 d of treatment. However, a reduction in chlorophyll content and an increase in membrane lipids peroxidation were observed. It is suggested that root structural alterations induced by As, such as the particular pattern of dark depositions in the vascular system, could be associated with an adaptation or detoxification mechanism to prevent As translocation to the aboveground tissues.

  2. Physiological Responses of Cotton at Seedling Stage to Waterlogged Stress

    Directory of Open Access Journals (Sweden)

    Kai-wen Liu

    2012-12-01

    Full Text Available In Jianghan plain as well as south China, cotton at seedling stage often encounter waterlogged stress, by which normal growth of cotton plants is affected, the purpose of the study is to analyze the responses to Waterlogging stress. Therefore flooding experiments of cotton in the seedling stage was made and a series of physiological indices were observed such as Chlorophyll Relative value (RC, chlorophyll fluorescence (F0, Fm, Malondialdehyde (MDA, nomadic Proline (Pro, Dissoluble Sugar (DS, Peroxidase (POD and Superoxide Dismutase (SOD, Analytic results indicated that, after Waterlogging, chlorophyll hydrolysis rate was higher in the first 3 days, the peak value of chlorophyll fluorescence decrease occurred between the 6th to 9th day. It figured that stagnant water on the field should be drained off in 3 days after Waterlogging stress, to avoid the photosynthetic efficiency being strongly inhibited. The balance of normal physiological metabolic process in cotton leaf was broken after Waterlogging, some new negative changes occurred, as MDA content increasing and the activity of SOD decline. Some other positive changes were accompanied, as the increasing of DS and Pro content and the activity of POD, for protecting active tissues. These physiological indices appeared regularly changing characterized by fastslow- fast, which can be simulated in unary cubic regression curve model.

  3. Cadmium interferes with maintenance of auxin homeostasis in Arabidopsis seedlings.

    Science.gov (United States)

    Hu, Yan Feng; Zhou, Guoying; Na, Xiao Fan; Yang, Lijing; Nan, Wen Bin; Liu, Xu; Zhang, Yong Qiang; Li, Jiao Long; Bi, Yu Rong

    2013-07-15

    Auxin and its homeostasis play key roles in many aspects of plant growth and development. Cadmium (Cd) is a phytotoxic heavy metal and its inhibitory effects on plant growth and development have been extensively studied. However, the underlying molecular mechanism of the effects of Cd stress on auxin homeostasis is still unclear. In the present study, we found that the root elongation, shoot weight, hypocotyl length and chlorophyll content in wild-type (WT) Arabidopsis seedlings were significantly reduced after exposure to Cd stress. However, the lateral root (LR) formation was markedly promoted by Cd stress. The level and distribution of auxin were both greatly altered in primary root tips and cotyledons of Cd-treated plants. The results also showed that after Cd treatment, the IAA content was significantly decreased, which was accompanied by increases in the activity of the IAA oxidase and alteration in the expression of several putative auxin biosynthetic and catabolic genes. Application of the auxin transport inhibitor, 1-naphthylphthalamic acid (NPA) and 1-naphthoxyacetic acid (1-NOA), reversed the effects of Cd on LR formation. Additionally, there was less promotion of LR formation by Cd treatment in aux1-7 and pin2 mutants than that in the WT. Meanwhile, Cd stress also altered the expression of PINs and AUX1 in Arabidopsis roots, implying that the auxin transport pathway is required for Cd-modulated LR development. Taken together, these findings suggest that Cd stress disturbs auxin homeostasis through affecting auxin level, distribution, metabolism, and transport in Arabidopsis seedling.

  4. Proteomic Study for Responses to Cadmium Stress in Rice Seedlings

    Institute of Scientific and Technical Information of China (English)

    GE Cai-lin; WANG Ze-gang; WAN Ding-zhen; DING Yan; WANG Yu-long; SHANG Qi; LUO Shi-shi

    2009-01-01

    A proteomic approach including two-dimensional electrophoresis and mass spectrometric (MALDI-TOF MS) analyses was used to investigate the responses to cadmium (Cd) stress in seedlings of rice (Oryza sativa L.) varieties Shanyou 63 and Aizaizhan. Cd stress significantly inhibited root and shoot growth, and affected the global proteome in rice roots and leaves, which induced or upregulated the expression of corresponding proteins in rice roots and leaves when rice seedlings were exposed to 0.1 or 1.0 mmol/L Cd. The Cd-induced proteins are involved in chelation and compartmentation of Cd, elimination of active oxygen free radicals, detoxification of toxic substances, degradation of denatured proteins or inactivated enzymes, regulation of physiologic metabolism and induction of pathogenesis-related proteins. Comparing the Cd-induced proteins between the two varieties, the β-glucosidase and pathogenesis-related protein family 10 proteins were more drastically induced by Cd stress in roots and leaves of Aizaizhan, and the UDP-glucose protein transglucosylase and translational elongation factor Tu were induced by 0.1 mmol/L Cd stress in roots of Shanyou 63. This may be one of the important mechanisms for higher tolerance to Cd stress in Shanyou 63 than in Aizaizhan.

  5. Effects of Post-Fire Plant Cover in the Performance of Two Cordilleran Cypress ( Austrocedrus chilensis) Seedling Stocktypes Planted in Burned Forests of Northeastern Patagonia, Argentina

    Science.gov (United States)

    Urretavizcaya, María F.; Gonda, Héctor E.; Defossé, Guillermo E.

    2017-03-01

    Cordilleran cypress ( Austrocedrus chilensis [D.Don] Pic. Serm. et Bizarri) forests occupy 140,000 ha along a sharp environmental gradient of central Andean-Patagonia in Argentina. Every summer, about 3200 ha of these forests are affected by wildfires, taking thereafter long time to recover. To accelerate forest recovery, we determined in xeric and mesic cypress stands burned 5 and 2 year before whether survival and growth of two planted cypress seedling stocktypes are affected by plant cover and contrasting precipitation conditions. Two experiments were conducted on each site, involving 100 replicates of two seedling stocktypes, having each significantly different morphological attributes. The experiments comprised a dry and humid growing season on each site. Both stocktypes performed similarly within stands, but differently between stands. In the xeric stand, plant cover had neutral effects on seedling survival, favored seedling height growth in the dry season, and was negative on collar diameter and stem growth. In the mesic site, high plant cover favored survival and height growth, but was inconsequential for collar diameter and stem growth. In this short-term post-fire period, and independent of precipitation received during both seasons (dry or humid), plant cover appears as playing a facilitative role, having neutral or even positive effects on survival and growth of planted seedlings. During the early post-fire successional stages, and besides seedling stocktype, there was a synergistic balance between light and soil moisture that seems to benefit planted seedling performance in burned cypress forests, and especially in mesic sites.

  6. Characterization of rhizobacteria associated with weed seedlings.

    Science.gov (United States)

    Kremer, R J; Begonia, M F; Stanley, L; Lanham, E T

    1990-06-01

    Rhizobacteria were isolated from seedlings of seven economically important weeds and characterized for potential phytopathogenicity, effects on seedling growth, and antibiosis to assess the possibility of developing deleterious rhizobacteria as biological control agents. The abundance and composition of rhizobacteria varied among the different weed species. For example, fluorescent pseudomonads represented from 11 to 42% of the total rhizobacterial populations from jimsonweed and lambsquarters, respectively. Other bacteria frequently isolated were nonfluorescent pseudomonads, Erwinia herbicola, Alcaligenes spp., and Flavobacterium spp. Only 18% of all isolates were potentially phytopathogenic, based on an Escherichia coli indicator bioassay. However, the proportion of isolates that inhibited growth in seedling assays ranged from 35 to 65% depending on the weed host. Antibiosis was most prevalent among isolates of fluorescent Pseudomonas spp., the activity of which was due to siderophore production in over 75% of these isolates. Overall, rhizobacterial isolates exhibited a complex array of properties that were inconsistent with accepted definitions for plant growth-promoting and deleterious rhizobacteria. It is suggested that for development of effective biological control agents for weed control, deleterious rhizobacteria must be screened directly on host seedlings and must possess several properties including high colonizing ability, specific phytotoxin production, and resistance or tolerance to antibiotics produced by other rhizosphere microorganisms, and they must either synthesize or utilize other bacterial siderophores.

  7. Factors affecting seedling regeneration of Liquidambar formosana in the L.formosana forests in hilly regions of Southeast Hubei,China%鄂东南低丘地区枫香林下枫香幼苗更新限制因子

    Institute of Scientific and Technical Information of China (English)

    王传华; 李俊清; 陈芳清; 杨莹

    2011-01-01

    Aims Liquidambarformosana is an important canopy tree species widely distributed in the plains and mountains from the north-subtropical zone to the tropical zone in China. Full understanding of the natural regeneration processes of tree seedling and limiting factors is important for plant population conservation and forest management. Our objective is to investigate the factors that limit seedling regeneration ofL. formosana under canopies of Formosan sweetgum forests in hilly regions of Southeast Hubei, China.Methods Seedling regeneration of L. formosana occurs sporadically under canopies of mixed pine forests but poorly under Formosan sweetgum canopy. In 2008, we carried out a series of experiments to study factors limiting seedling regeneration of L. formosana under mixed pine forests and Formosan sweetgum forests and tested: (1) effects of lower temperature and soil moisture on seed longevity, (2) effects of forest type, soil type and litter cover on seed survival, (3) litter allelopathy effects on seed longevity and germination, and (4) effects of light intensity under canopies on seedling survival.Important findings Dispersed seeds of L. formosana could germinate immediately at lower temperatures (4-8℃), although such temperatures were fatal to seedling establishment. Contrary to our prediction, soil type, litter leachate and litter cover had no effects on L. formosana seed viability and could not be used to explain poor seedling regeneration under canopies of Formosan sweetgum forest. We also did not find any litter leachate inhibition or promotion effects on seed germination, although a short germination lag effect was found with leachate of pine needles and sweetgum leaves. Shading first-year seedlings of L. formosana indicated that about 90% would die under the canopy of the Formosan sweetgum forest (with its 3% transmittance of open-sky light). In general, our experiments suggested that non-dormant seed and shade-intolerant seedlings of L

  8. Deposition of antibacterial of poly(1,3-bis-(p-carboxyphenoxy propane)-co-(sebacic anhydride)) 20:80/gentamicin sulfate composite coatings by MAPLE

    Energy Technology Data Exchange (ETDEWEB)

    Cristescu, R., E-mail: rodica.cristescu@inflpr.ro [National Institute for Lasers, Plasma and Radiation Physics, Lasers Department, Atomistilor 409, P.O. Box MG-36, RO-077125 Bucharest-Magurele (Romania); Popescu, C.; Socol, G.; Visan, A.; Mihailescu, I.N. [National Institute for Lasers, Plasma and Radiation Physics, Lasers Department, Atomistilor 409, P.O. Box MG-36, RO-077125 Bucharest-Magurele (Romania); Gittard, S.D.; Miller, P.R. [Joint Department of Biomedical Engineering, North Carolina State University, Raleigh, NC 27695 (United States); Joint Department of Biomedical Engineering, University of North Carolina, Chapel Hill, NC 27514 (United States); Martin, T.N. [Joint Department of Biomedical Engineering, North Carolina State University, Raleigh, NC 27695 (United States); Narayan, R.J. [Joint Department of Biomedical Engineering, North Carolina State University, Raleigh, NC 27695 (United States); Joint Department of Biomedical Engineering, University of North Carolina, Chapel Hill, NC 27514 (United States); Andronie, A.; Stamatin, I. [University of Bucharest, 3 Nano-SAE Research Center, P.O. Box MG-38, Bucharest-Magurele (Romania); Chrisey, D.B. [Rensselaer Polytechnic Institute, Department of Materials Science and Engineering, Troy, 12180-3590 NY (United States)

    2011-04-01

    We report on thin film deposition of poly(1,3-bis-(p-carboxyphenoxy propane)-co-sebacic anhydride)) 20:80 thin films containing several gentamicin concentrations by matrix assisted pulsed laser evaporation (MAPLE). A pulsed KrF* excimer laser was used to deposit the polymer-drug composite thin films. Release of gentamicin from these MAPLE-deposited polymer conjugate structures was assessed. Fourier transform infrared spectroscopy was used to demonstrate that the functional groups of the MAPLE-transferred materials were not changed by the deposition process nor were new functional groups formed. Scanning electron microscopy confirmed that MAPLE may be used to fabricate thin films of good morphological quality. The activity of gentamicin-doped films against Escherichia coli and Staphylococcus aureus bacteria was demonstrated using disk diffusion and antibacterial drop test. Our studies indicate that deposition of polymer-drug composite thin films prepared by MAPLE is a suitable technique for performing controlled drug delivery. Antimicrobial thin film coatings have several medical applications, including use for indwelling catheters and implanted medical devices.

  9. Impact of Resonant Infrared Matrix-Assisted Pulsed Laser Evaporation (RIR-MAPLE) on Morphology and Charge Conduction in Conjugated Polymer and Bulk Heterojunction Thin Films

    Science.gov (United States)

    Stiff-Roberts, Adrienne; McCormick, Ryan; Atewologun, Ayomide

    2014-03-01

    An approach to improve organic photovoltaic efficiency is to increase vertical charge conduction by promoting out-of-plane π- π stacking in conjugated polymers. Resonant infrared matrix-assisted pulsed laser evaporation (RIR-MAPLE) features multiple growth parameters that can be varied to achieve a desired organic thin film property. In addition, RIR-MAPLE enables nanoscale domains in blended polymeric films and multi-layer polymeric films regardless of constituent solubility. Thus, RIR-MAPLE deposition is compared to solution-cast films as a possible approach to increase out-of-plane charge transport in polymers and bulk heterojunctions. Two common, solar cell polymers are investigated: P3HT and PCPDTBT. Materials characterization includes grazing-incidence, wide angle x-ray scattering (GIWAXS) for structural information and two techniques to determine hole mobility: organic field effect transistors to measure in-plane mobility and charge extraction by linearly increasing voltage to measure out-of-plane mobility. Initial indications are that the RIR-MAPLE films have a fundamentally different morphology compared to solution-cast films. In the case of P3HT, an enhancement in out-of-plane π- π stacking was observed by GIWAXS in RIR-MAPLE films compared to solution-cast films. A portion of this research was conducted at CNMS at ORNL.

  10. The effect of ammonium ions on the activity of glutamate dehydrogenase, alanine aminotransferase and aspartate aminotransferase in Cucumis sativus L. seedlings

    Directory of Open Access Journals (Sweden)

    Genowefa Kubiak-Dobosz

    2014-02-01

    Full Text Available Changes in the activity of glutamate dehydrogenase (GDH, alanine aminotransferase (GPT and aspartate aminotransferase (GOT were studied in various organs of Cucumis sativus L. seedlings in relation to the uptake of mineral nitrogen (in form of N03- or NH4+ from the medium. Activity of GDH, GPT, and GOT was higher in young leaves and roots of cucumber seedlings if the plants developed- in an ammonium medium. No similar changes of aminotransferases activity were noted in the cotyledons. Factors affecting varying effect of ammonium ions upon GPT and GOT activity are discussed for particular organs of cucumber seedlings.

  11. Water management in hardening Maytenus ilicifolia (Schrad. Planch. seedlings

    Directory of Open Access Journals (Sweden)

    João Alexandre Lopes Dranski

    2017-02-01

    Full Text Available This study evaluated the effects of seedling height and irrigation management on M. ilicilofia seedlings. The experiment used a completely randomized design in a 2 x 3 factorial arrangement. Seedlings of two height classes (greater than or less than 18.0 cm were subjected to three irrigation regimes (daily irrigation, irrigation every other day, and gradual reduction of irrigation. After eight weeks, the morphophysiological and performance attributes of the seedlings were quantified. Gradual reduction of irrigation promoted the highest rate of net carbon assimilation. Irrigating every other day resulted in greater secondary growth rate, biomass accumulation in the shoot and root tissues, and lower electrolyte leakage rate. After planting, these treatments maintained higher leaf relative water content (RWC. RWC in seedlings smaller than 18 cm was significantly higher until the third week after planting. Therefore, larger seedlings submitted to hardening by gradually reducing irrigation improves seedling quality.

  12. Dying piece by piece: carbohydrate dynamics in aspen seedlings under severe carbon stress and starvation

    Science.gov (United States)

    Wiley, Erin; Chow, Pak; Landhäusser, Simon

    2016-04-01

    Carbon stress and starvation remain poorly understood in trees, despite their potential role in mortality from a variety of agents. To explore the effects of carbon stress on nonstructural carbohydrate (NSC) dynamics and recovery potential and to examine the process of starvation, we grew aspen seedlings under one of three levels of shade: 40% (light shade), 8% (medium shade), and 4% (dark shade) of full sunlight. We then exposed seedlings to 24 hours darkness at either 20° or 28° C until trees had died. Periodically, seedlings were harvested for NSC analysis and to measure stem and root respiration. In addition, some seedlings were moved back into the light to determine if recovery was possible at certain points during starvation. Specifically, we sought to address the following questions: 1) Do NSC concentrations or mass influence tree survival under carbon stress? 2) At what carbohydrate levels do trees fail to recover and starve? 3) Does temperature affect the NSC level at which trees starve? Increasing shade reduced growth, but surprisingly did not reduce NSC levels, except in a portion of deep shade seedlings that experienced dieback. Once in darkness, leaves died first, with final NSC levels ranging from ~4% (Medium shade, 28 degrees) to 7.5% (Light shade). Stem death generally occurred gradually down the stem. Stem tissues retained ~1-2% NSC when dead. Recovery was still possible when only the upper half of the stem had died; at this point, seedlings had relatively high root NSC levels in their remaining roots (7-10%), with 1-3% starch. No trees recovered after the whole stem had died, at which point, some trees root systems were completely dead. However, most retained substantial amounts of live roots, averaging 5-6% NSC, with 0.25-1.5% starch. Despite the initially similar NSC concentrations, light shade seedlings took longer to reach half stem and whole stem death than seedlings from medium and dark shade. Longer survival times were associated with

  13. Challenges in forest reclamation of marginal lands: a balance between site conditions and seedling quality

    Science.gov (United States)

    Landhäusser, Simon

    2017-04-01

    Forest loss and degradation is occurring worldwide, but at the same time efforts in forest restoration are ever increasing. While approaches to restoration often follow specific stakeholder objectives, regional climates and the degree of site degradation also play an important role in the prioritization of restoration efforts. Often the restoration of degraded lands can satisfy only few measurable objectives; however, to design and restore resistant and resilient ecosystems that can adapt to changing conditions, there is a need for new and adaptive management approaches. Mining and other resource extraction industries are affecting more and more forested areas worldwide. A priority in the reclamation and certification of forest lands disturbed by industrial activity is their expeditious redevelopment to functioning forests. To rehabilitate these heavily disturbed areas back to forest ecosystems, planting of trees remains one of the most effective strategies for the redevelopment of a continuous tree canopy on a site. It is well understood that access to good quality seedling stock is essential to achieve establishment success and early growth of seedlings. However, most reclamation areas have challenging initial site conditions and these conditions are often not a single factor but a combination of factors that can be additive or synergistic. Therefore successful forest restoration on degraded lands needs to consider multiple objectives and approaches to minimize trade-offs in achieving these objectives. To meet these demands, new methods for the production and evaluation of seedling stock types are needed to ensure that that seedlings are fit to grow on a wide range of site conditions or are particularly designed to grow in very specific conditions. Generally, defining seedling quality is difficult as it is species specific and results have been mixed; likely influenced by site conditions, further reiterating the need to carefully evaluate sites allowing

  14. Effects of Different Pretreatments to the Seed on Seedling Emergence and Growth of Acacia polyacantha

    Directory of Open Access Journals (Sweden)

    Edward Missanjo

    2014-01-01

    Full Text Available Acacia polyacantha Willd. is a multipurpose tree species prioritised as one of the agroforestry tree species in Malawi. However, its use in agroforestry practices is limited by the low seedling growth and survival at the nursery stage. A study was conducted to evaluate the seedling growth and survival of Acacia polyacantha as affected by different pretreatments on the seeds at Malawi College of Forestry and Wildlife nursery, Malawi. Seeds were subjected to five presowing seed treatments methods, namely, immersion in cold water at room temperature for 24 hours, immersion in hot water (100°C for 5 minutes, immersion in concentrated sulfuric acid (0.3 M H2SO4 for 20 minutes, scarification by mechanically nicking using secateurs, and a control where seeds were sown without any treatment. The results indicate that presowing seed treatments have positive influence on the seedling growth and survival percentage. Nicked seeds exhibited the highest significant (P<0.001 performance for vegetative characteristics of height, root collar diameter, number of leaves, and survival percentage compared to other pretreatments. Therefore, it is suggested to use nicking as a pretreatment method on Acacia polyacantha seeds in order to enhance the speed and the amount of early seedling growth at the nursery stage.

  15. Seed vigor, antioxidant metabolism and initial growth characteristics of red rice seedlings under different light intensities

    Directory of Open Access Journals (Sweden)

    Tiago Zanatta Aumonde

    2013-06-01

    Full Text Available This work aimed to evaluate the effect that different intensities of light have on the physiological attributes of red rice seeds and seedlings. Before and after emergence, seedlings were exposed to light levels of 35%; 65% and 100% in a greenhouse. We evaluated shoots and roots, in terms of length and dry mass, as well as leaf area and content of chlorophyll (a,b and total. In leaves and roots, we quantified the activity of superoxide dismutase (SOD, ascorbate peroxidase (APX, catalase (CAT and guaiacol peroxidase (POX. We determined the leaf area ratio (F A, leaf mass ratio (F W, specific leaf area (S A, and shoot/root ratio (P W. At higher light intensities, shoot length decreased, whereas root length, dry mass and number of tillers increased. Leaf area was greatest in seedlings exposed to a 65% light level. The F A, F W, S A and P W were lowest at a light intensity of 100%. Differences in light intensity had qualitative and quantitative effects on chlorophyll contents. The activity of SOD and CAT was higher at lower light levels, whereas the inverse was true for APX and POX activity. Extremes of light availability alter the activity of antioxidant enzymes, negatively affecting the initial growth characteristics and photosynthetic pigments of red rice seedlings.

  16. Water Level Effects on Growth of Melaleuca Seedlings from Lake Okeechobee (Florida, USA) Littoral Zone.

    Science.gov (United States)

    LOCKHART; AUSTIN; AUMEN

    1999-05-01

    / The invasive exotic wetland tree, Melaleuca quinquenervia, is expanding rapidly throughout seasonally wet areas of southern Florida (USA), including the littoral zone of Lake Okeechobee. Natural resource managers are concerned that a lower lake level regulation schedule under consideration for Lake Okeechobee, while potentially beneficial to overall ecosystem health, might increase the rate of Melaleuca expansion. To investigate this possibility, Melaleuca saplings (harvested from the littoral zone) and 7-week-old seedlings (grown from harvested seeds) were subjected to various hydroperiod treatments in replicated mesocosms. Hydroperiod treatments were selected based on a simulation of historical water level variations. Saplings grew taller under longer hydroperiods with fluctuating water levels, including periods of submersion. Time since germination affected the response of seedlings to inundation. Submersed 7-week-old seedlings grew slower and had less biomass than submersed 12-week-old seedlings, yet mortality was low at both ages. Melaleuca's plasticity allows it to adapt to hypoxic, aquatic conditions by means of aquatic heterophylly and adventitious roots. Algae and drought also increased mortality. Based on faster growth of Melaleuca under longer hydroperiods and its adaptability to seasonal flooding, a lower lake regulation schedule may not stimulate its expansion. Therefore, water levels should not be manipulated only to control Melaleuca. Control of Melaleuca should continue using current practices such as manual removal or chemical treatment. KEY WORDS: Melaleuca; Lake Okeechobee; Littoral zone; Water level; Regulation schedule

  17. Eco-physiological Characteristics of Alfalfa Seedlings in Response to Various Mixed Salt-alkaline Stresses

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Soil salinization and alkalization frequently co-occur in nature, but little is known about the mixed effects of salt-alkaline stresses on plants. An experiment with mixed salts (NaCl, Na2SO4, NaHCO3 and Na2CO3) and 30 salt-alkaline combinations(salinity 24-120 mmol/L and pH 7.03-10.32) treating Medicago sativa seedlings was conducted. The results demonstrated that salinity and alkalinity significantly affected total biomass and biomass components of seedlings. There were interactive effects of salt composition and concentration on biomass (P ≤ 0.001). The interactions between salinity and alkalinity stresses led to changes in the root activity along the salinity gradient (P ≤ 0.001). The effects of alkalinity on seedling survival rate were more significant than those of salinity, and the seedlings demonstrated some physiological responses(leaf electrolyte leakage rate and proline content) in order to adapt to mixed salt-alkaline stresses. It was concluded that the mixed salt-alkaline stresses, which differ from either salt or alkali stress, emphasize the significant interaction between salt concentration (salinity) and salt component (alkalinity). Further, the effects of the interaction between high alkalinity and salinity are more severe than those of either salt or alkali stress, and such a cooperative interaction results in more sensitive responses of ecological and physiological characteristics in plants.

  18. Effects of soil nitrogen:phosphorus ratio on growth rate of Artemisia ordosica seedlings

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    To address how the ratios of nitrogen and phosphorus (N:P ratios) in soil affect plant growth, we performed a two-factor (soil available N:P ratios and plant density) randomized block pot experiment to examine the relationships between soil N:P ratios, and the N:P ratios and growth rate of Artemisia ordosica seedlings. Under moderate water stress and adequate nutrient status, both soil N:P and plant density influenced the N:P ratios and growth rates of A. ordosica. With the increase of soil N:P ratios, the growth rates of A. ordosica seedlings decreased significantly. With the increase of soil N:P ratios, N:P ratios in A. ordosica seedlings increased significantly. While the nitrogen concentrations in the plant increased slightly, the phosphorus concentrations significantly decreased. With the increase of plant density, the shoot N:P ratios and growth rates significantly decreased, which resulted from soil N:P ratios. Thus, soil N:P ratios influenced the N:P ratios in A. ordosica seedlings, and hence, influenced its growth. Our results suggest that, under adequate nutrient environment, soil N:P ratios can be a limiting factor for plant growth.

  19. On the biomechanics of seedling anchorage

    Science.gov (United States)

    Crouzy, Benoît; Edmaier, Katharina; Perona, Paolo

    2014-05-01

    We propose a minimal model for the response of vegetation to pullout constraints at early development stage. We try to capture both the average mechanical properties of the root system and the stochastic component of the uprooting process of seedlings. We identify a minimal set of relevant physical components in the purpose of quantifying the uprooting process: length of the root fibres, elastic response of the fibres and adhesion between the roots and the soil matrix. We present for validation a dataset extracted from Edmaier et al. (under revision), accounting for 98 uprooting experiments using Avena sativa L. seedlings (common oat), growing in non-cohesive sediment under controlled conditions. The corresponding root system has a very simple architecture, with three root fibres of different lengths. The response of the system to the constraint is however complex: the stress-strain signal presents sudden jumps followed by partial elastic recoveries. The analysis of the jumps and partial recoveries gives an insight into the resilience of the system. The anchorage of less mature seedlings rapidly collapses after the peak force has been reached, while more mature seedlings usually recover from partial failures. We explore this crossover with our validation dataset. The type of seedlings we study has been used in flume experiments investigating the feedbacks between the vegetation and the river morphodynamics (see for example Perona et al. (2012)). An understanding of the characteristics of the uprooting curve (maximal uprooting force and total uprooting work) of such vegetation reveals the ability of seedlings to withstand environmental constraints in terms of duration or intensity (see Edmaier et al., under revision), and is therefore helpful for planning future experiments. REFERENCES - P. Perona, P. Molnar, B. Crouzy, E. Perucca, Z. Jiang, S. McLelland, D. Wüthrich, K. Edmaier, R. Francis, C. Camporeale, et al., Biomass selection by floods and related timescales

  20. The MaPLE device of Saha Institute of Nuclear Physics: construction and its plasma aspects.

    Science.gov (United States)

    Pal, Rabindranath; Biswas, Subir; Basu, Subhasis; Chattopadhyay, Monobir; Basu, Debjyoti; Chaudhuri, Manis; Chowdhuri, Manis

    2010-07-01

    The Magnetized Plasma Linear Experimental (MaPLE) device is a low cost laboratory plasma device at Saha Institute of Nuclear Physics fabricated in-house with the primary aim of studying basic plasma physics phenomena such as plasma instabilities, wave propagation, and their nonlinear behavior in magnetized plasma regime in a controlled manner. The machine is specially designed to be a versatile laboratory device that can provide a number of magnetic and electric scenario to facilitate such studies. A total of 36 number of 20-turn magnet coils, designed such as to allow easy handling, is capable of producing a uniform, dc magnetic field of about 0.35 T inside the plasma chamber of diameter 0.30 m. Support structure of the coils is planned in an innovative way facilitating straightforward fabrication and easy positioning of the coils. Further special feature lies in the arrangement of the spacers between the coils that can be maneuvered rather easily to create different magnetic configurations. Various methods of plasma production can be suitably utilized according to the experimental needs at either end of the vacuum vessel. In the present paper, characteristics of a steady state plasma generated by electron cyclotron resonance method using 2.45 GHz microwave power are presented. Scans using simple probe drives revealed that a uniform and long plasma column having electron density approximately 3-5x10(10) cm(-3) and temperature approximately 7-10 eV, is formed in the center of the plasma chamber which is suitable for wave launching experiments.

  1. Forest floor community metatranscriptomes identify fungal and bacterial responses to N deposition in two maple forests

    Directory of Open Access Journals (Sweden)

    Cedar N Hesse

    2015-04-01

    Full Text Available Anthropogenic N deposition alters patterns of C and N cycling in temperate forests, where forest floor litter decomposition is a key process mediated by a diverse community of bacteria and fungi. To track forest floor decomposer activity we generated metatranscriptomes that simultaneously surveyed the actively expressed bacterial and eukaryote genes in the forest floor, to compare the impact of N deposition on the decomposers in two natural maple forests in Michigan, USA, where replicate field plots had been amended with N for 16 years. Site and N amendment responses were compared using about 75,000 carbohydrate active enzyme transcript sequences (CAZymes in each metatranscriptome. Parallel ribosomal RNA surveys of bacterial and fungal biomass and taxonomic composition showed no significant differences in either biomass or OTU richness between the two sites or in response to N. Site and N amendment were not significant variables defining bacterial taxonomic composition, but they were significant for fungal community composition, explaining 17 and 14% of the variability, respectively. The relative abundance of expressed bacterial and fungal CAZymes changed significantly with N amendment in one of the forests, and N-response trends were also identified in the second forest. Although the two ambient forests were similar in community biomass, taxonomic structure and active CAZyme profile, the shifts in active CAZyme profiles in response to N-amendment differed between the sites. One site responded with an over-expression of bacterial CAZymes, and the other site responded with an over-expression of both fungal and different bacterial CAZymes. Both sites showed reduced representation of fungal lignocellulose degrading enzymes in N-amendment plots. The metatranscriptome approach provided a holistic assessment of eukaryote and bacterial gene expression and is applicable to other systems where eukaryotes and bacteria interact.

  2. Light drives vertical gradients of leaf morphology in a sugar maple (Acer saccharum) forest.

    Science.gov (United States)

    Coble, Adam P; Cavaleri, Molly A

    2014-02-01

    Leaf mass per area (LMA, g m(-2)) is an essential trait for modeling canopy function due to its strong association with photosynthesis, respiration and leaf nitrogen. Leaf mass per area, which is influenced by both leaf thickness and density (LMA = thickness × density), generally increases from the bottom to the top of tree canopies, yet the mechanisms behind this universal pattern are not yet resolved. For decades, the light environment was assumed to be the most influential driver of within-canopy variation in LMA, yet recent evidence has shown hydrostatic gradients to be more important in upper canopy positions, especially in tall evergreen trees in temperate and tropical forests. The aim of this study was to disentangle the importance of various environmental drivers on vertical LMA gradients in a mature sugar maple (Acer saccharum Marshall) forest. We compared LMA, leaf density and leaf thickness relationships with height, light and predawn leaf water potential (ΨPre) within a closed and an exposed canopy to assess leaf morphological traits at similar heights but different light conditions. Contrary to our expectations and recent findings in the literature, we found strong evidence that light was the primary driver of vertical gradients in leaf morphology. At similar heights (13-23 m), LMA was greater within the exposed canopy than the closed canopy, and light had a stronger influence over LMA compared with ΨPre. Light also had a stronger influence over both leaf thickness and density compared with ΨPre; however, the increase in LMA within both canopy types was primarily due to increasing leaf thickness with increasing light availability. This study provides strong evidence that canopy structure and crown exposure, in addition to height, should be considered as a parameter for determining vertical patterns in LMA and modeling canopy function.

  3. Forest floor community metatranscriptomes identify fungal and bacterial responses to N deposition in two maple forests.

    Science.gov (United States)

    Hesse, Cedar N; Mueller, Rebecca C; Vuyisich, Momchilo; Gallegos-Graves, La Verne; Gleasner, Cheryl D; Zak, Donald R; Kuske, Cheryl R

    2015-01-01

    Anthropogenic N deposition alters patterns of C and N cycling in temperate forests, where forest floor litter decomposition is a key process mediated by a diverse community of bacteria and fungi. To track forest floor decomposer activity we generated metatranscriptomes that simultaneously surveyed the actively expressed bacterial and eukaryote genes in the forest floor, to compare the impact of N deposition on the decomposers in two natural maple forests in Michigan, USA, where replicate field plots had been amended with N for 16 years. Site and N amendment responses were compared using about 74,000 carbohydrate active enzyme transcript sequences (CAZymes) in each metatranscriptome. Parallel ribosomal RNA (rRNA) surveys of bacterial and fungal biomass and taxonomic composition showed no significant differences in either biomass or OTU richness between the two sites or in response to N. Site and N amendment were not significant variables defining bacterial taxonomic composition, but they were significant for fungal community composition, explaining 17 and 14% of the variability, respectively. The relative abundance of expressed bacterial and fungal CAZymes changed significantly with N amendment in one of the forests, and N-response trends were also identified in the second forest. Although the two ambient forests were similar in community biomass, taxonomic structure and active CAZyme profile, the shifts in active CAZyme profiles in response to N-amendment differed between the sites. One site responded with an over-expression of bacterial CAZymes, and the other site responded with an over-expression of both fungal and different bacterial CAZymes. Both sites showed reduced representation of fungal lignocellulose degrading enzymes in N-amendment plots. The metatranscriptome approach provided a holistic assessment of eukaryote and bacterial gene expression and is applicable to other systems where eukaryotes and bacteria interact.

  4. Large-Scale Variations in Lumber Value Recovery of Yellow Birch and Sugar Maple in Quebec, Canada.

    Directory of Open Access Journals (Sweden)

    Mariana Hassegawa

    Full Text Available Silvicultural restoration measures have been implemented in the northern hardwoods forests of southern Quebec, Canada, but their financial applicability is often hampered by the depleted state of the resource. To help identify sites most suited for the production of high quality timber, where the potential return on silvicultural investments should be the highest, this study assessed the impact of stand and site characteristics on timber quality in sugar maple (Acer saccharum Marsh. and yellow birch (Betula alleghaniensis Britt.. For this purpose, lumber value recovery (LVR, an estimate of the summed value of boards contained in a unit volume of round wood, was used as an indicator of timber quality. Predictions of LVR were made for yellow birch and sugar maple trees contained in a network of more than 22000 temporary sample plots across the Province. Next, stand-level variables were selected and models to predict LVR were built using the boosted regression trees method. Finally, the occurrence of spatial clusters was verified by a hotspot analysis. Results showed that in both species LVR was positively correlated with the stand age and structural diversity index, and negatively correlated with the number of merchantable stems. Yellow birch had higher LVR in areas with shallower soils, whereas sugar maple had higher LVR in regions with deeper soils. The hotspot analysis indicated that clusters of high and low LVR exist across the province for both species. Although it remains uncertain to what extent the variability of LVR may result from variations in past management practices or in inherent site quality, we argue that efforts to produce high quality timber should be prioritized in sites where LVR is predicted to be the highest.

  5. Supplement Analysis for the Transmission System Vegetation Management Program FEIS (DOE/EIS-0285/SA-62) - Rocky Reach - Maple Valley

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Mark A. [Bonneville Power Administration (BPA), Portland, OR (United States)

    2002-04-16

    Vegetation Management along the Rocky Reach – Maple Valley No. 1 Transmission Line ROW from structure 98/2 to structure 110/1. The transmission line is a 500 kV line. BPA proposes to clear targeted vegetation along access roads and around tower structures that may impede the operation and maintenance of the subject transmission line. BPA plans to conduct vegetation management along existing access road and around structure landings for the purpose of maintaining access to structures site. All work will be in accordance with the National Electrical Safety Code and BPA standards.

  6. A Maple Package on Symbolic Computation of Conserved Densities for (1+1)-Dimensional Nonlinear Evolution Systems

    Institute of Scientific and Technical Information of China (English)

    YANG Xu-Dong; RUAN Hang-Yu; LOU Sen-Yue

    2007-01-01

    A new algorithm for symbolic computation of polynomial-type conserved densities for nonlinear evolution systems is presented. The algorithm is implemented in Maple. The improved algorithm is more efficient not only in removing the redundant terms of the general form of the conserved densities but also in solving the conserved densities with the associated flux synchronously without using Euler operator. Furthermore, the program conslaw. mpl can be used to determine the preferences for a given parameterized nonlinear evolution systems. The code is tested on several well-known nonlinear evolution equations from the soliton theory.

  7. Supplement Analysis for the Transmission System Vegetation Management Program FEIS (DOE/EIS-0285/SA-60) - Rocky Reach - Maple Valley No. 1

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Mark A. [Bonneville Power Administration (BPA), Portland, OR (United States)

    2002-04-15

    Vegetation Management along the Rocky Reach – Maple Valley No. 1 Transmission Line ROW from structure 110/1 to the Maple Valley Substation. The transmission line is a 500 kV line. BPA proposes to clear targeted vegetation along access roads and around tower structures that may impede the operation and maintenance of the subject transmission line. BPA plans to conduct vegetation management along existing access road and around structure landings for the purpose of maintaining access to structures site. All work will be in accordance with the National Electrical Safety Code and BPA standards.

  8. Multiple amine oxidases in cucumber seedlings.

    Science.gov (United States)

    Percival, F W; Purves, W K

    1974-10-01

    Cell-free extracts of cucumber (Cucumis sativus L. cv. National Pickling) seedlings were found to have amine oxidase activity when assayed with tryptamine as a substrate. Studies of the effect of lowered pH on the extract indicated that this activity was heterogeneous, and three amine oxidases could be separated by ion exchange chromatography. The partially purified enzymes were tested for their activities with several substrates and for their sensitivities to various amine oxidase inhibitors. One of the enzymes may be a monoamine oxidase, although it is inhibited by some diamine oxidase inhibitors. The other two enzymes have properties more characteristic of the diamine oxidases. The possible relationship of the amine oxidases to indoleacetic acid biosynthesis in cucumber seedlings is discussed.

  9. Fungi causing dying out of heather seedlings

    Directory of Open Access Journals (Sweden)

    Maria Kowalik

    2012-12-01

    Full Text Available The aim of the study was to determine the fungi causing dying out of one-yearold heather seedlings. Observations were carried out on: 'Amethyst', 'Annemarie', 'Colette', 'Perestroika' and 'Reini'. The shoots revealing necrotic symptoms were plated on PDA medium. 25 species of fungi were isolated. Among them Pestalotia sydowiana, Alternaria alternata, Cylindrocarpon destructans, Leptosphaeria coniothyrium and Epicoccum purpurascens were dominant, while Mammaria echinobotryoides, Phoma leveillei, Kaissleriella subalpina, Botrytis cinerea and Phytophthora cinnamomi occurred less frequently.

  10. Fungi causing dying out of heather seedlings

    OpenAIRE

    Maria Kowalik; Agnieszka Wandzel

    2012-01-01

    The aim of the study was to determine the fungi causing dying out of one-yearold heather seedlings. Observations were carried out on: 'Amethyst', 'Annemarie', 'Colette', 'Perestroika' and 'Reini'. The shoots revealing necrotic symptoms were plated on PDA medium. 25 species of fungi were isolated. Among them Pestalotia sydowiana, Alternaria alternata, Cylindrocarpon destructans, Leptosphaeria coniothyrium and Epicoccum purpurascens were dominant, while Mammaria echinobotryoides, Phoma leveille...

  11. Pathogenicity of P. terrestris on Maize Seedlings

    Directory of Open Access Journals (Sweden)

    Jelena Lević

    2012-01-01

    Full Text Available Pathogenicity of P. terrestris was determined by the Knop’s medium slants method intest tubes. Isolates originated from the roots of maize (Zea mays L., barley (Hordeum vulgareL., Johnson grass (Sorghum halepense Pers., sorghum (Sorghum bicolour (L. Moench., garlic(Allium sativum L., onion (Allium cepa L., barnyard millet (Echinochloa crus-galli (L. P.Beauv.and green foxtail (Setaria viridis (L. P.B.. A fragment of a fungal colony, cultivated on PDA,was placed on the bottom of Knop’s medium slant in each test tube and then steriliseda maize seed was placed 2 cm away from the inoculum. After 21-day inoculation of seeds,the intensity of the development of symptoms on maize seedlings was estimated. The reddishor dark pigment on the root, mesocotyl and/or coleoptyl of seedlings was an indicatorfor the infection by the fungus under in vitro conditions. Based on the pathogenicity test,the isolates were classified into the following three groups: slightly (3 isolates, moderately(6 isolates and very pathogenic (6 isolates to maize seedlings. The obtained results showthat P. terrestris, originating from different hosts, can be a maize pathogen. These resultscan explain the high frequency and high incidence of this fungus on maize roots in Serbia.

  12. Frost heaving of planted tree seedlings in the boreal forest of northern Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Goulet, France

    2000-07-01

    Frost heaving can be a leading cause of tree seedling mortality in many places in the boreal forest of Northern Sweden. The aim of this investigation was to improve our understanding of frost heaving of planted tree seedlings as related to snow cover, scarification, planting methods and soil types. The thesis is based on a review paper, three field experiments and one laboratory experiment. The experiments focus on different methods to control frost heaving of forest tree seedlings and on a number of factors affecting the extent of frost heaving. The review paper identifies the many aspects of frost heaving of forest tree seedlings and agricultural crops based on an intensive review of the research contributions made during the last century. Even if many investigations have been carried out with the aim to decrease the extent of frost heaving, very little quantitative results are available for tree seedlings. In a field experiment, the choice of planting positions was effective in decreasing frost heaving of planted seedlings following mounding or disc-trenching. Seedlings planted in the depressions were largely affected by frost heaving with a maximal vertical displacement of 5.4 cm while frost heaving did not occur on the top of the mound. On the other hand, the planting time and planting depth had no influence on the extent of frost heaving. In another field experiment the size of the scarified patches was strongly correlated to frost heaving which reached between 7.6 and 11.5 cm in 4 and 8-dm patches compared to between 4.4 and 5.3 in non-scarified soil and in a 1-dm patch. Ground vegetation probably decreases the diurnal temperature variation and the number of freezing-thawing cycles. The duration and magnitude of frost temperatures, the frost hour sum, increased with patch size. The difference between the 8-dm and 1-dm patch increased to 2064 hour-degrees at the end of the winter. In larger patches, the planting depth seemed to be effective in reducing the

  13. Nutrient partitioning and seedling development in the genus Leucaena

    Energy Technology Data Exchange (ETDEWEB)

    Dovel, R.L.

    1987-01-01

    Slow establishment of the genus Leucaena from seed has been attributed to law seedling vigor and late nodulation. Observation of early seedling growth indicated that partitioning of a large proportion of resources to the root of young Leucaena seedlings could account, in part, for the slow initial shoot growth observed in this genus. Therefore, a series of experiments were conducted to examine the partitioning of stored seed reserves, photosynthate, and nitrogen in developing Leucaena seedlings. The effects of nodulation and nitrogen fertilization on partitioning of nutrients in the seedling were also examined. Seed reserves were initially used for radicle growth in dark grown seedlings; however, partitioning soon shifted to the hypocotyl. By four days after imbibition, hypocotyl weight exceeded radicle weight in both species tested (L. leucocephala and L. retusa), at all temperatures above 20/sup 0/C. Two experiments were conducted examining the carbon partitioning of L. leucocephala cultivar K-8 using /sup 14/CO/sub 2/ pulse labeling techniques.

  14. Propagation of Cucumber Seedlings in Different Organic and Inorganic Media

    Directory of Open Access Journals (Sweden)

    H. Cinkilİc

    2008-05-01

    Full Text Available The objective of this study is to investigate the possibility of using grape marc and cinder an alternative media to peat for cucumber propagation and find out the results.In the study;normal grape marc, normal grape marc+25% süper coarse perlite, ground grape marc+25% süper coarse perlite, cinder+25% süper coarse perlite, peat+25% süper coarse perlite and peat were used, the best results were obtained from grape marc + 25% super coarse perlite in stem diameter, number of true leaves, weight of seedling, width of seedling, length of leaves and width of leaves; from peat + 25% super coarse perlite in length of seedling, length of seedling with root, weight of root, weight of seedling with root and length of root. The cinder which is the residue of burned coal, gave the worst results in all seedling properties.

  15. Steam treatment of forest ground vegetation to improve tree seedling establishment and growth

    Energy Technology Data Exchange (ETDEWEB)

    Norberg, Gisela [Swedish Univ. of Agricultural Sciences, Umeaa (Sweden). Dept. of Forest Vegetation Ecology

    2000-07-01

    Mechanical soil scarification is the commonly used site preparation technique in Sweden today and there is a need for alternative site preparation methods to fulfil some environmental goals in Swedish forestry. Thermal vegetation control could be an alternative method that reduces the competing forest ground vegetation with minimal disturbance to the mineral soil and ground floor. The aim with this work has been to investigate if it is possible to control forest ground vegetation by steam treatment as an alternative site preparation method before planting or seeding. Studies were conducted on four sites, each representing main Swedish forest vegetation types, i.e. the ground vegetation was dominated by crowberry (Empetrum hermaphroditum Hagerup), bilberry (Vaccinium myrtillus L.), heather (Calluna vulgaris (L.) Hull) and wavy hair grass (Deschampsia flexuosa (L.) Trin). Steam generally controlled recolonization of vegetation on all investigated sites for a longer time than soil scarification. Especially in controlling grass vegetation steam treatment was much more effective than soil scarification. The establishment and growth of seeded Scots pine seedlings also improved after vegetation control by steam treatment compared to that in intact vegetation. For all sites, both steam treatment and soil scarification improved seedling height growth compared to seedlings planted in intact vegetation. In the bilberry and heather dominated sites seedling growth in steam treated plots was even better than for seedlings planted in mechanical soil scarified plots. Further, key biological soil processes such as microbial activity and mycorrhizal colonisation were not negatively affected by steam treatment. The conclusion made from these studies is that steam treatment has the potential to be used as an alternative site preparation method especially on sites dominated by ericaceous vegetation. However, the method requires some further technical development before it may be used

  16. Seed treatment with Trichoderma harzianum alleviates biotic, abiotic, and physiological stresses in germinating seeds and seedlings.

    Science.gov (United States)

    Mastouri, Fatemeh; Björkman, Thomas; Harman, Gary E

    2010-11-01

    Trichoderma spp. are endophytic plant symbionts that are widely used as seed treatments to control diseases and to enhance plant growth and yield. Although some recent work has been published on their abilities to alleviate abiotic stresses, specific knowledge of mechanisms, abilities to control multiple plant stress factors, their effects on seed and seedlings is lacking. We examined the effects of seed treatment with T. harzianum strain T22 on germination of seed exposed to biotic stress (seed and seedling disease caused by Pythium ultimum) and abiotic stresses (osmotic, salinity, chilling, or heat stress). We also evaluated the ability of the beneficial fungus to overcome physiological stress (poor seed quality induced by seed aging). If seed were not under any of the stresses noted above, T22 generally had little effect upon seedling performance. However, under stress, treated seed germinated consistently faster and more uniformly than untreated seeds whether the stress was osmotic, salt, or suboptimal temperatures. The consistent response to varying stresses suggests a common mechanism through which the plant-fungus association enhances tolerance to a wide range of abiotic stresses as well as biotic stress. A common factor that negatively affects plants under these stress conditions is accumulation of toxic reactive oxygen species (ROS), and we tested the hypothesis that T22 reduced damages resulting from accumulation of ROS in stressed plants. Treatment of seeds reduced accumulation of lipid peroxides in seedlings under osmotic stress or in aged seeds. In addition, we showed that the effect of exogenous application of an antioxidant, glutathione, or application of T22, resulted in a similar positive effect on seed germination under osmotic stress or in aged seed. This evidence supports the model that T. harzianum strain T22 increases seedling vigor and ameliorates stress by inducing physiological protection in plants against oxidative damage.

  17. Uptake and translocation of phytochemical 2-benzoxazolinone (BOA) in radish seeds and seedlings.

    Science.gov (United States)

    Chiapusio, Geneviève; Pellissier, François; Gallet, Christiane

    2004-07-01

    The molecular aspects of phytochemical interactions between plants, especially the process of phytochemical translocation by the target plant, remain challenging for those studying allelopathy. 2-Benzoxazolinone (BOA) is a natural chemical produced by rye (Secale cereale) and is known to have phytotoxic effects on weed seeds and seedlings. The translocation of BOA into target plants has been poorly investigated. Therefore, the total absorption of [ring U 14C] BOA was estimated by oxidizing whole seedlings of Raphanus sativus cv. for 8 days and quantifying the radioactivity. Non-radiolabelled BOA in seedlings was also estimated by HPLC. BOA applied at 10(-3) M was readily taken up by germinated radish at a rate of 1556 nmol g(-1) FW. At these same concentrations, BOA reduced radish germination by 50% and caused a delay in radicle elongation. Exogenous BOA was responsible for the observed germination inhibition. At a concentration of 10(-5) M, BOA was taken up by germinated seeds (31 nmol g(-1) FW), but this quantity did not affect radish germination. Labelled BOA was not mineralized in the culture medium during seedling growth as no 14CO2 was recovered. Both 10(-3) and 10(-5) M BOA were translocated into radish organs, mainly into roots and cotyledons. These organs were then identified as potential physiological target sites. Cotyledons remained the target sink (44% of the total radioactivity). The kinetics of BOA uptake at 10(-3) and 10(-5) M in radish seedlings was identical: BOA accumulation was proportional to its initial concentration. A comparison between radioactivity and HPLC quantification for 10(-3) M BOA indicated that BOA (along with some metabolites) could effectively be recovered in radish organs using chromatography.

  18. Longleaf pine bud development: influence of seedling nutrition

    Science.gov (United States)

    J. P. Barnett; D. P. Jackson; R. K. Dumroese

    2010-01-01

    A subset of seedlings from a larger study (Jackson and others 2006, 2007) were selected and evaluated for two growing seasons to relate bud development, and root-collar diameter (RCD), and height growth with three nursery fertilization rates. We chose seedlings in the 0.5 (lowest), 2.0 (mid-range), and 4.0 (highest) mg of nitrogen per seedling treatments. Buds moved...

  19. Containers of Attalea funifera fibers to produce eucalyptus seedlings

    OpenAIRE

    Andrea Vita Reis Mendonça; Lucas Gonçalves Ribeiro; José Roque Azevedo Assunção; Teresa Aparecida Soares de Freitas; Josival Santos Souza

    2016-01-01

    The aim of this study was to assess the technical feasibility of using biodegradable containers made of fiber waste of Attalea funifera Martius to produce seedling of Eucalyptus camaldulensis Dehnh. The work was carried out in three stages: manufacture of piassava fiber containers, seedling production and field simulation. The experiment of seedling production was in completely randomized design, with two treatments (polyethylene tube and biodegradable container) and 10 repetitions, with 64 s...

  20. The effects of heat treatment on physical properties and surface roughness of red-bud maple (Acer trautvetteri Medw.) wood.

    Science.gov (United States)

    Korkut, Derya Sevim; Guller, Bilgin

    2008-05-01

    Heat treatment is often used to improve the dimensional stability of wood. In this study, the effects of heat treatment on physical properties and surface roughness of red-bud maple (Acer trautvetteri Medw.) wood were examined. Samples obtained from Düzce Forest Enterprises, Turkey, were subjected to heat treatment at varying temperatures and durations. The physical properties of heat-treated samples were compared against controls in order to determine their; oven-dry density, air-dry density, and swelling properties. A stylus method was employed to evaluate the surface characteristics of the samples. Roughness measurements, using the stylus method, were made in the direction perpendicular to the fiber. Three main roughness parameters; mean arithmetic deviation of profile (Ra), mean peak-to-valley height (Rz), and maximum roughness (Rmax) obtained from the surface of wood, were used to evaluate the effect of heat treatment on the surface characteristics of the specimens. Significant differences were determined (p>0.05) between surface roughness parameters (Ra, Rz, Rmax) at three different temperatures and three periods of heat treatment. The results showed that the values of density, swelling and surface roughness decreased with increasing temperature treatment and treatment times. Red-bud maple wood could be utilized successfully by applying proper heat treatment techniques without any losses in investigated parameters. This is vital in areas, such as window frames, where working stability and surface smoothness are important factors.

  1. Ethanol production from hot-water sugar maple wood extract hydrolyzate: fermentation media optimization for Escherichia coli FBWHR

    Directory of Open Access Journals (Sweden)

    Yang Wang

    2015-04-01

    Full Text Available We report the first time statistical study of the optimization for ethanol production from hot-water sugar maple hemicellulosic wood hydrolyzate by Escherichia coli FBWHR. Response surface methodology was employed to investigate the effect of fermentation media on the ethanol production from concentrated hot-water sugar maple hemicellulosic wood extract hydrolyzate by Escherichia coli FBWHR. The critical media components were firstly selected according to Plackett–Burman design and further optimized by central composite design. Based on the response surface analysis, the optimum concentrations of the significant components were obtained: yeast extract, 10.19 g/L; tryptone, 14.55 g/L; Na2HPO4•7H2O, 23.21 g/L; KH2PO4, 5 g/L and NH4Cl, 2 g/L. An ethanol concentration of 15.23 ± 0.21 g/L was achieved under the optimized media, which agreed with the predicted value. Ethanol production was enhanced to 22.18 ± 0.13 g/L by scaling up the fermentation from shaker flask to 1.3 L bioreactor.

  2. Antimicrobial activity of biopolymeric thin films containing flavonoid natural compounds and silver nanoparticles fabricated by MAPLE: A comparative study

    Science.gov (United States)

    Cristescu, R.; Visan, A.; Socol, G.; Surdu, A. V.; Oprea, A. E.; Grumezescu, A. M.; Chifiriuc, M. C.; Boehm, R. D.; Yamaleyeva, D.; Taylor, M.; Narayan, R. J.; Chrisey, D. B.

    2016-06-01

    The purpose of this study was to investigate the interactions between microorganisms, including the planktonic and adherent organisms, and biopolymer (polyvinylpyrrolidone), flavonoid (quercetin dihydrate and resveratrol)-biopolymer, and silver nanoparticles-biopolymer composite thin films that were deposited using matrix assisted pulsed laser evaporation (MAPLE). A pulsed KrF* excimer laser source was used to deposit the aforementioned composite thin films, which were characterized using Fourier transform infrared spectroscopy (FT-IR), infrared microscopy (IRM), scanning electron microscopy (SEM), Grazing incidence X-ray diffraction (GIXRD) and atomic force microscopy (AFM). The antimicrobial activity of thin films was quantified using an adapted disk diffusion assay against Gram-positive and Gram-negative bacteria strains. FT-IR, AFM and SEM studies confirmed that MAPLE may be used to fabricate thin films with chemical properties corresponding to the input materials as well as surface properties that are appropriate for medical use. The silver nanoparticles and flavonoid-containing films exhibited an antimicrobial activity both against Gram-positive and Gram-negative bacterial strains demonstrating the potential use of these hybrid systems for the development of novel antimicrobial strategies.

  3. Conspecific Leaf Litter-Mediated Effect of Conspecific Adult Neighborhood on Early-Stage Seedling Survival in A Subtropical Forest

    Science.gov (United States)

    Liu, Heming; Shen, Guochun; Ma, Zunping; Yang, Qingsong; Xia, Jianyang; Fang, Xiaofeng; Wang, Xihua

    2016-11-01

    Conspecific adults have strong negative effect on the survival of nearby early-stage seedlings and thus can promote species coexistence by providing space for the regeneration of heterospecifics. The leaf litter fall from the conspecific adults, and it could mediate this conspecific negative adult effect. However, field evidence for such effect of conspecific leaf litter remains absent. In this study, we used generalized linear mixed models to assess the effects of conspecific leaf litter on the early-stage seedling survival of four dominant species (Machilus leptophylla, Litsea elongate, Acer pubinerve and Distylium myricoides) in early-stage seedlings in a subtropical evergreen broad-leaved forest in eastern China. Our results consistently showed that the conspecific leaf litter of three species negatively affected the seedling survival. Meanwhile, the traditional conspecific adult neighborhood indices failed to detect this negative conspecific adult effect. Our study revealed that the accumulation of conspecific leaf litter around adults can largely reduce the survival rate of nearby seedlings. Ignoring it could result in underestimation of the importance of negative density dependence and negative species interactions in the natural forest communities.

  4. The value of trophic interactions for ecosystem function: dung beetle communities influence seed burial and seedling recruitment in tropical forests.

    Science.gov (United States)

    Griffiths, Hannah M; Bardgett, Richard D; Louzada, Julio; Barlow, Jos

    2016-12-14

    Anthropogenic activities are causing species extinctions, raising concerns about the consequences of changing biological communities for ecosystem functioning. To address this, we investigated how dung beetle communities influence seed burial and seedling recruitment in the Brazilian Amazon. First, we conducted a burial and retrieval experiment using seed mimics. We found that dung beetle biomass had a stronger positive effect on the burial of large than small beads, suggesting that anthropogenic reductions in large-bodied beetles will have the greatest effect on the secondary dispersal of large-seeded plant species. Second, we established mesocosm experiments in which dung beetle communities buried Myrciaria dubia seeds to examine plant emergence and survival. Contrary to expectations, we found that beetle diversity and biomass negatively influenced seedling emergence, but positively affected the survival of seedlings that emerged. Finally, we conducted germination trials to establish the optimum burial depth of experimental seeds, revealing a negative relationship between burial depth and seedling emergence success. Our results provide novel evidence that seed burial by dung beetles may be detrimental for the emergence of some seed species. However, we also detected positive impacts of beetle activity on seedling recruitment, which are probably because of their influence on soil properties. Overall, this study provides new evidence that anthropogenic impacts on dung beetle communities could influence the structure of tropical forests; in particular, their capacity to regenerate and continue to provide valuable functions and services.

  5. Effect of temperature on biomass allocation in seedlings of two contrasting genotypes of the oilseed crop Ricinus communis.

    Science.gov (United States)

    Ribeiro, Paulo R; Zanotti, Rafael F; Deflers, Carole; Fernandez, Luzimar G; Castro, Renato D de; Ligterink, Wilco; Hilhorst, Henk W M

    2015-08-01

    Ricinus communis is becoming an important crop for oil production, and studying the physiological and biochemical aspects of seedling development may aid in the improvement of crop quality and yield. The objective of this study was to assess the effect of temperature on biomass allocation in two R. communis genotypes. Biomass allocation was assessed by measuring dry weight of roots, stems, and cotyledons of seedlings grown at three different temperatures. Root length of each seedling was measured. Biomass allocation was strongly affected by temperature. Seedlings grown at 25°C and 35°C showed greater biomass than seedlings grown at 20°C. Cotyledon and stem dry weight increased for both genotypes with increasing temperature, whereas root biomass allocation showed a genotype-dependent behavior. Genotype MPA11 showed a continuous increase in root dry weight with increasing temperature, while genotype IAC80 was not able to sustain further root growth at higher temperatures. Based on metabolite and gene expression profiles, genotype MPA11 increases its level of osmoprotectant molecules and transcripts of genes encoding for antioxidant enzymes and heat shock proteins to a higher extent than genotype IAC80. This might be causal for the ability to maintain homeostasis and support root growth at elevated temperatures in genotype MPA11. Copyright © 2015 Elsevier GmbH. All rights reserved.

  6. Methyl jasmonate stimulates biosynthesis of 2-phenylethylamine, phenylacetic acid and 2-phenylethanol in seedlings of common buckwheat.

    Science.gov (United States)

    Horbowicz, Marcin; Wiczkowski, Wiesław; Sawicki, Tomasz; Szawara-Nowak, Dorota; Sytykiewicz, Hubert; Mitrus, Joanna

    2015-01-01

    Methyl jasmonate has a strong effect on secondary metabolizm in plants, by stimulating the biosynthesis a number of phenolic compounds and alkaloids. Common buckwheat (Fagopyrum esculentum Moench) is an important source of biologically active compounds. This research focuses on the detection and quantification of 2-phenylethylamine and its possible metabolites in the cotyledons, hypocotyl and roots of common buckwheat seedlings treated with methyl jasmonate. In cotyledons of buckwheat sprouts, only traces of 2-phenylethylamine were found, while in the hypocotyl and roots its concentration was about 150 and 1000-times higher, respectively. Treatment with methyl jasmonate resulted in a 4-fold increase of the 2-phenylethylamine level in the cotyledons of 7-day buckwheat seedlings, and an 11-fold and 5-fold increase in hypocotyl and roots, respectively. Methyl jasmonate treatment led also to about 4-fold increase of phenylacetic acid content in all examined seedling organs, but did not affect the 2-phenylethanol level in cotyledons, and slightly enhanced in hypocotyl and roots. It has been suggested that 2-phenylethylamine is a substrate for the biosynthesis of phenylacetic acid and 2-phenylethanol, as well as cinnamoyl 2-phenethylamide. In organs of buckwheat seedling treated with methyl jasmonate, higher amounts of aromatic amino acid transaminase mRNA were found. The enzyme can be involved in the synthesis of phenylpyruvic acid, but the presence of this compound could not be confirmed in any of the examined organs of common buckwheat seedling.

  7. AVOCADO SEEDLINGS MULTIPLE STEMS PRODUCTION

    Directory of Open Access Journals (Sweden)

    MARCUS VINICIUS SANDOVAL PAIXÃO

    2016-01-01

    Full Text Available ABSTRACT This study aimed to evaluate the potential of multi-stems in avocado seeds according to their mass as well as the adventitious rooting of multi-stem budding with or without the use of auxin. The research was carried out at the Vegetation House of Federal Institute of Espírito Santo, Campus Santa Teresa -ES, with seeds of different masses: 100 g, in which each experimental unit was made of five seeds, distributed within five repetitions, under a completely randomized design. The seeds were put to germinate and the percentage number of emergence and multiple stems were evaluated. After 150 days, the following evaluations were carried out: survival of rooted cuttings; number of leaves; stem diameter; root length; root volume; root and shoot fresh mass; root and shoot dry mass; shoot height; absolute growth and shoot growth rate; shoot dry weight/root dry mass ratio; shoot height/stem diameter ratio; shoot height/root length and Dickson's quality index ratio. Avocado seeds with mass over 100 g and between 81-100 g presented higher percentage of multiple stems. Rods over 20 cm that were not treated with IBA (indole-3-butyric acid resulted on avocado plants of better quality. The use of IBA (2000 mg L-1 does not affect the rooting and growth of avocado's multi-stem plants.

  8. Contrasting nurse plants and nurse rocks: The spatial distribution of seedlings of two sub-Antarctic species

    Science.gov (United States)

    Haussmann, N. S.; McGeoch, M. A.; Boelhouwers, J. C.

    2010-05-01

    Positive plant interactions, such as those associated with nurse plants, have been suggested to dominate over negative interactions in environments with high abiotic stress. Here we demonstrate that the sub-Antarctic cushion plant species, Azorella selago (Apiaceae), positively affects the distribution of both its own seedlings and those of the perennial grass, Agrostis magellanica (Poaceae). As a result of the light weight and small size of seeds of both species, coupled with strong winds experienced in the study area, we consider it unlikely that these patterns are the result of very localized seed dispersal from the study cushions themselves. Instead, we suggest that both cushions and rocks act as seed traps, trapping seeds dispersed by wind, runoff and/or downslope sediment transport through frost creep. In addition, increased A. selago seedling numbers around cushions, but not around rocks, suggest that cushions provide a biological nurse effect, such as improving soil nutrient status or providing mychorrizae, to seedlings of their own kind.

  9. Traditional uses, phytochemistry, and pharmacology of the genus Acer (maple): A review.

    Science.gov (United States)

    Bi, Wu; Gao, Ying; Shen, Jie; He, Chunnian; Liu, Haibo; Peng, Yong; Zhang, Chunhong; Xiao, Peigen

    2016-08-02

    The genus Acer (Aceraceae), commonly known as maple, comprises approximately 129 species that primarily grow in the northern hemisphere, especially in the temperate regions of East Asia, eastern North America, and Europe. These plants have been traditionally used to treat a wide range of diseases in East Asia and North America. Moreover, clinical studies have shown that medicinal plants belonging to Acer are highly effective in the treatment of rheumatism, bruises, hepatic disorders, eye disease, and pain, and in detoxification. This review provides a systematic and constructive overview of the traditional uses, chemical constituents, and pharmacological activities of plants of the genus Acer. This review is based on a literature study of scientific journals and books from libraries and electronic sources such as SciFinder, ScienceDirect, Springer, PubMed, CNKI, Google Scholar, Baidu Scholar, and Web of Science. The literature in this review related to chemical constituents and pharmacological activities dates from 1922 to the end of October 2015. Furthermore, ethnopharmacological information on this genus was obtained from libraries and herbaria in China and USA. In traditional medicine, 40 species, 11 subspecies, and one varieta of the genus Acer are known to exhibit a broad spectrum of biological activities. To date, 331 compounds have been identified from 34 species of the genus Acer, including flavonoids, tannins, phenylpropanoids, diarylheptanoids, terpenoids, benzoic acid derivatives, and several other types of compounds, such as phenylethanoid glycosides and alkaloids. Preliminary pharmacological studies have shown that the extracts and compounds isolated from this genus exhibit a broad spectrum of biological activities such as antioxidant, antitumor, anti-inflammatory, antidiabetic, hepatoprotective, and antiobesity activities, as well as promoting osteoblast differentiation. To date, reports on the toxicity of Acer species to humans are very limited, and

  10. Interactive effects of juvenile defoliation, light conditions, and interspecific competition on growth and ectomycorrhizal colonization of Fagus sylvatica and Pinus sylvestris seedlings.

    Science.gov (United States)

    Trocha, Lidia K; Weiser, Ewa; Robakowski, Piotr

    2016-01-01

    Seedlings of forest tree species are exposed to a number of abiotic (organ loss or damage, light shortage) and biotic (interspecific competition) stress factors, which may lead to an inhibition of growth and reproduction and, eventually, to plant death. Growth of the host and its mycorrhizal symbiont is often closely linked, and hence, host damage may negatively affect the symbiont. We designed a pot experiment to study the response of light-demanding Pinus sylvestris and shade-tolerant Fagus sylvatica seedlings to a set of abiotic and biotic stresses and subsequent effects on ectomycorrhizal (ECM) root tip colonization, seedling biomass, and leaf nitrogen content. The light regime had a more pronounced effect on ECM colonization than did juvenile damage. The interspecific competition resulted in higher ECM root tip abundance for Pinus, but this effect was insignificant in Fagus. Low light and interspecific competition resulted in lower seedling biomass compared to high light, and the effect of the latter was partially masked by high light. Leaf nitrogen responded differently in Fagus and Pinus when they grew in interspecific competition. Our results indicated that for both light-demanding (Pinus) and shade-tolerant (Fagus) species, the light environment was a major factor affecting seedling growth and ECM root tip abundance. The light conditions favorable for the growth of seedlings may to some extent compensate for the harmful effects of juvenile organ loss or damage and interspecific competition.

  11. Exogenous Spermidine Alleviates Low Temperature Injury in Mung Bean (Vigna radiata L. Seedlings by Modulating Ascorbate-Glutathione and Glyoxalase Pathway

    Directory of Open Access Journals (Sweden)

    Kamrun Nahar

    2015-12-01

    Full Text Available The role of exogenous spermidine (Spd in alleviating low temperature (LT stress in mung bean (Vigna radiata L. cv. BARI Mung-3 seedlings has been investigated. Low temperature stress modulated the non-enzymatic and enzymatic components of ascorbate-glutathione (AsA-GSH cycle, increased H2O2 content and lipid peroxidation, which indicate oxidative damage of seedlings. Low temperature reduced the leaf relative water content (RWC and destroyed leaf chlorophyll, which inhibited seedlings growth. Exogenous pretreatment of Spd in LT-affected seedlings significantly increased the contents of non-enzymatic antioxidants of AsA-GSH cycle, which include AsA and GSH. Exogenous Spd decreased dehydroascorbate (DHA, increased AsA/DHA ratio, decreased glutathione disulfide (GSSG and increased GSH/GSSG ratio under LT stress. Activities of AsA-GSH cycle enzymes such as ascorbate peroxidase (APX, monodehydroascorbate reductase (MDHAR, dehydroascorbate reductase (DHAR and glutathione reductase (GR increased after Spd pretreatment in LT affected seedlings. Thus, the oxidative stress was reduced. Protective effects of Spd are also reflected from reduction of methylglyoxal (MG toxicity by improving glyoxalase cycle components, and by maintaining osmoregulation, water status and improved seedlings growth. The present study reveals the vital roles of AsA-GSH and glyoxalase cycle in alleviating LT injury.

  12. The effects of fire severity on ectomycorrhizal colonization and morphometric features in Pinus pinaster Ait. seedlings

    Directory of Open Access Journals (Sweden)

    Pablo Vásquez-Gassibe

    2016-04-01

    Full Text Available Aim of the study: Mycorrhizal fungi in Mediterranean forests play a key role in the complex process of recovery after wildfires. A broader understanding of an important pyrophytic species as Pinus pinaster and its fungal symbionts is thus necessary for forest restoration purposes. This study aims to assess the effects of ectomycorrhizal symbiosis on maritime pine seedlings and how fire severity affects fungal colonization ability.Area of study: Central Spain, in a Mediterranean region typically affected by wildfires dominated by Pinus pinaster, a species adapted to fire disturbance.Material and Methods: We studied P. pinaster root apexes from seedlings grown in soils collected one year after fire in undisturbed sites, sites moderately affected by fire and sites highly affected by fire. Natural ectomycorrhization was observed at the whole root system level as well as at two root vertical sections (0-10 cm and 10-20 cm. We also measured several morphometric traits (tap root length, shoot length, dry biomass of shoots and root/shoot ratio, which were used to test the influence of fire severity and soil chemistry upon them.Main results: Ectomycorrhizal colonization in undisturbed soils for total and separated root vertical sections was higher than in soils that had been affected by fire to some degree. Inversely, seedling vegetative size increased according to fire severity.Research highlights: Fire severity affected soil properties and mycorrhizal colonization one year after occurrence, thus affecting plant development. These findings can contribute to a better knowledge of the factors mediating successful establishment of P. pinaster in Mediterranean forests after wildfires. 

  13. The effects of fire severity on ectomycorrhizal colonization and morphometric features in Pinus pinaster Ait. seedlings

    Energy Technology Data Exchange (ETDEWEB)

    Vásquez-Gassibe, P.; Oria-de-Rueda, J.A.; Santos-del-Blanco, L.; Martín-Pinto, P.

    2016-07-01

    Aim of study: Mycorrhizal fungi in Mediterranean forests play a key role in the complex process of recovery after wildfires. A broader understanding of an important pyrophytic species as Pinus pinaster and its fungal symbionts is thus necessary for forest restoration purposes. This study aims to assess the effects of ectomycorrhizal symbiosis on maritime pine seedlings and how fire severity affects fungal colonization ability. Area of study: Central Spain, in a Mediterranean region typically affected by wildfires dominated by Pinus pinaster, a species adapted to fire disturbance. Material and Methods: We studied P. pinaster root apexes from seedlings grown in soils collected one year after fire in undisturbed sites, sites moderately affected by fire and sites highly affected by fire. Natural ectomycorrhization was observed at the whole root system level as well as at two root vertical sections (0-10 cm and 10-20 cm). We also measured several morphometric traits (tap root length, shoot length, dry biomass of shoots and root/shoot ratio), which were used to test the influence of fire severity and soil chemistry upon them. Main results: Ectomycorrhizal colonization in undisturbed soils for total and separated root vertical sections was higher than in soils that had been affected by fire to some degree. Inversely, seedling vegetative size increased according to fire severity. Research highlights: Fire severity affected soil properties and mycorrhizal colonization one year after occurrence, thus affecting plant development. These findings can contribute to a better knowledge of the factors mediating successful establishment of P. pinaster in Mediterranean forests after wildfires. (Author)

  14. Potent endogenous allelopathic compounds in Lepidium sativum seed exudate: effects on epidermal cell growth in Amaranthus caudatus seedlings.

    Science.gov (United States)

    Iqbal, Amjad; Fry, Stephen C

    2012-04-01

    Many plants exude allelochemicals--compounds that affect the growth of neighbouring plants. This study reports further studies of the reported effect of cress (Lepidium sativum) seed(ling) exudates on seedling growth in Amaranthus caudatus and Lactuca sativa. In the presence of live cress seedlings, both species grew longer hypocotyls and shorter roots than cress-free controls. The effects of cress seedlings were allelopathic and not due to competition for resources. Amaranthus seedlings grown in the presence of cress allelochemical(s) had longer, thinner hypocotyls and shorter, thicker roots--effects previously attributed to lepidimoide. The active principle was more abundant in cress seed exudate than in seedling (root) exudates. It was present in non-imbibed seeds and releasable from heat-killed seeds. Release from live seeds was biphasic, starting rapidly but then continuing gradually for 24 h. The active principle was generated by aseptic cress tissue and was not a microbial digestion product or seed-treatment chemical. Crude seed exudate affected hypocotyl and root growth at ~25 and ~450 μg ml(-1) respectively. The exudate slightly (28%) increased epidermal cell number along the length of the Amaranthus hypocotyl but increased total hypocotyl elongation by 129%; it resulted in a 26% smaller hypocotyl circumference but a 55% greater epidermal cell number counted round the circumference. Therefore, the effect of the allelochemical(s) on organ morphology was imposed primarily by regulation of cell expansion, not cell division. It is concluded that cress seeds exude endogenous substances, probably including lepidimoide, that principally regulate cell expansion in receiver plants.

  15. Water availability influences morphology, mycorrhizal associations, PSII efficiency and polyamine metabolism at early growth phase of Scots pine seedlings.

    Science.gov (United States)

    Muilu-Mäkelä, Riina; Vuosku, Jaana; Läärä, Esa; Saarinen, Markku; Heiskanen, Juha; Häggman, Hely; Sarjala, Tytti

    2015-03-01

    Scots pine (Pinus sylvestris L.) is adapted to various soil types with diverse water availabilities. However, Scots pine seedlings are vulnerable to abiotic stress during the early growth, when they may be exposed to both dry and wet conditions. Here, we focused on the above and below ground coping strategies of Scots pine seedlings under controlled wet, optimal and dry soil conditions by investigating morphological traits including seedling biomass, number of root tips, proportion of mycorrhizal root tips and brown needles. In addition, we studied metabolic and physiological responses including gene expression involved in biosynthesis and catabolism of polyamines (PA), PSII efficiency and the expression of the catalase (CAT) late-embryogenesis abundant protein (LEA), pyruvate decarboxylase (PDC), glutamate-cysteine ligase (GCL) and glutathione synthetase (GS) genes. We found that seedlings invested in shoots by maintaining stable shoot water content and high PSII efficiency under drought stress. Free and soluble conjugated putrescine (Put) accumulated in needles under drought stress, suggesting the role of Put in protection of photosynthesizing tissues. However, the expression of the PA biosynthesis genes, arginine decarboxylase (ADC), spermidine synthase (SPDS) and thermospermine synthase (ACL5) was not affected under drought stress whereas catabolizing genes diamino oxidase (DAO) and polyamine oxidase (PAO) were down-regulated in shoots. The morphology of the roots was affected by peat water content. Furthermore, both drought stress and water excess restricted the seedling ability to sustain a symbiotic relationship. The consistent pattern of endogenous PAs seems to be advantageous to the Scots pine seedlings also under stress conditions.

  16. Long-term calcium addition increases growth release, wound closure, and health of sugar maple (Acer saccharum) trees at the Hubbard Brook Experimental Forest

    Science.gov (United States)

    Brett A. Huggett; Paul G. Schaberg; Gary J. Hawley; Christopher Eager

    2007-01-01

    We surveyed and wounded forest-grown sugar maple (Acer saccharum Marsh.) trees in a long-term, replicated Ca manipulation study at the Hubbard Brook Experimental Forest in New Hampshire, USA. Plots received applications of Ca (to boost Ca availability above depleted ambient levels) or A1 (to compete with Ca uptake and further reduce Ca availability...

  17. On the Least-Squares Fitting of Slater-Type Orbitals with Gaussians: Reproduction of the STO-NG Fits Using Microsoft Excel and Maple

    Science.gov (United States)

    Pye, Cory C.; Mercer, Colin J.

    2012-01-01

    The symbolic algebra program Maple and the spreadsheet Microsoft Excel were used in an attempt to reproduce the Gaussian fits to a Slater-type orbital, required to construct the popular STO-NG basis sets. The successes and pitfalls encountered in such an approach are chronicled. (Contains 1 table and 3 figures.)

  18. Cold-season patterns of reserve and soluble carbohydrates in sugar maple and ice-damaged trees of two age classes following drought

    Science.gov (United States)

    B. L. Wong; K. L. Baggett; A. H. Rye

    2009-01-01

    This study examines the effects of summer drought on the composition and profiles of cold-season reserve and soluble carbohydrates in sugar maple (Acer saccharum Marsh.) trees (50-100 years old or ~200 years old) in which the crowns were nondamaged or damaged by the 1998 ice storm. The overall cold season reserve...

  19. Enhancing Stand Structure through Snag Creation in Northeastern U.S. Forests: Using Ethanol Injections and Bark Beetle Pheromones to Artificially Stress Red Maple and White Pine

    Directory of Open Access Journals (Sweden)

    Kevin J. Dodds

    2016-06-01

    Full Text Available We investigated two methods to create white pine and red maple snags in a forested setting. The first involved injecting trees with ethanol at two times (single Ethanol (ETOH and double ETOH injections to increase attractiveness to insects and elicit attacks on trees. The second method was unique to white pines and involved both injection treatments in combination with baiting trees with Ips-specific pheromones. Three of five white pines from the double ETOH treatment died in the second year. Species including Ips pini (Say, Ips grandicollis Eichhoff, Orthotomicus caelatus Eichhoff, Crypturgus borealis Swaine and Monochamus notatus (Drury responded more strongly to at least one of the treatments over control trees. However, there were no differences found in individual Scolytinae or Cerambycidae species response to treatments in red maple. Fitness (FV/FM and vitality (PIabs were both significantly reduced in both ETOH treatments compared to controls in white pine. In red maple, fitness was reduced in the double ETOH treated trees but the final mean FV/FM values were within the approximate optimal of health. Ethanol injections, in combination with Ips-specific semiochemicals, show promise for creating standing coarse woody debris (CWD in white pine. Injecting ethanol was not effective for stressing red maple.

  20. On the Least-Squares Fitting of Slater-Type Orbitals with Gaussians: Reproduction of the STO-NG Fits Using Microsoft Excel and Maple

    Science.gov (United States)

    Pye, Cory C.; Mercer, Colin J.

    2012-01-01

    The symbolic algebra program Maple and the spreadsheet Microsoft Excel were used in an attempt to reproduce the Gaussian fits to a Slater-type orbital, required to construct the popular STO-NG basis sets. The successes and pitfalls encountered in such an approach are chronicled. (Contains 1 table and 3 figures.)

  1. Effect of peat-based container media on establishment of Scots pine, Norway spruce and silver birch seedlings after transplanting in contrasting water conditions

    Energy Technology Data Exchange (ETDEWEB)

    Heiskanen, Juha; Rikala, Risto [Finnish Forest Research Inst., Suonenjoki (Finland). Suonenjoki Research Station

    2000-07-01

    Container seedlings were grown in pure sphagnum peat and peat mixtures containing coarse perlite and/or fine sand 25% by volume. Soil-water availability and rooting of the seedlings into the surrounding sandy soil after transplanting were studied in contrasting soil-water conditions in a greenhouse and a field experiment. No clear benefit was found for seedling rooting and establishment after planting by adding the used constituents to peat container medium. In fact, rooting of pine and birch was greatest in pure peat medium. Weakened seedlings occurred most frequently in media containing fine sand with lower water retention (in the matric potential range - 1 to - 10 kPa) than in pure peat or peat containing perlite. Preplanting and postplanting watering clearly affected soil-water relations and seedling performance. Wet container media were found to release the most easily retained water into the soil within hours after planting. The amount of water released into coarse planting soil was less than that released into fine soil. Dry container media absorbed water from the soil for several days after planting, but still remained drier for a few days than those watered prior to planting. Preplanting watering decreased the mortality of conifer seedlings, and promoted their rooting into the soil, height growth and needle mass, but did not do so for birch. Postplanting watering did not affect mortality, but it promoted height growth and needle and leaf mass of all three species and rooting of birch. The results emphasize the importance of the water-retention characteristics of container media and of watering seedlings before outplanting for seedling establishment, especially in dry growth conditions.

  2. Habitat-related variation in seedling recruitment of Gentiana pannonica

    Science.gov (United States)

    Ekrtová, Ester; Košnar, Jan

    2012-11-01

    Differences in seedling recruitment of Gentiana pannonica were investigated between the primary (relict) and the secondary (semi-natural) forest-free habitats of the Bohemian Forest (870-1200 m a.s.l.) and of the Alps (1045-1935 m a.s.l.) to understand the factors promoting the seedling recruitment of G. pannonica and their importance for species distribution, population structure, and conservation. In the communities with adult plants of G. pannonica, we recorded environmental variables (the slope, the altitude, and the covers of bare ground, litter, and rocks), estimated parameters of the vegetation (the covers of herbs, bryophytes, and dwarf shrubs), and counted the seedlings of G. pannonica. In a field experiment, we investigated seedling survival under different soil moisture regimes. We also observed seasonal dynamics of seedling recruitment in permanent plots over the course of three years. In the primary habitats of both regions, G. pannonica grew in a relatively wide range of communities, and its seedlings occurred in each area. In the secondary habitats of the Bohemian Forest, a very low frequency of the seedlings was recorded. The number of seedlings increased with the covers of the moss layer and of bare soil and decreased with the cover of the herb layer, especially of graminoids. The seedling mortality was significantly lower in the plots with higher soil moistures, and the emergence of new-born seedlings was concentrated in the spring season, when the soil received a high water supply due to melting of snow. For the successful generative reproduction of G. pannonica, our findings highlight the critical importance of the microsites with low levels of competition and of sufficient soil moisture G. pannonica. It seems that because of the long-term lack of grazing disturbances, the structures of the secondary habitats of G. pannonica in the Bohemian Forest have become unfavourable for seedling establishment and generative reproduction of this threatened

  3. Tolerance of Mycorrhiza infected pistachio (Pistacia vera L.) seedling to drought stress under glasshouse conditions.

    Science.gov (United States)

    Abbaspour, H; Saeidi-Sar, S; Afshari, H; Abdel-Wahhab, M A

    2012-05-01

    The influence of Glomus etunicatum colonization on plant growth and drought tolerance of 3-month-old Pistacia vera seedlings in potted culture was studied in two different water treatments. The arbuscular mycorrhiza (AM) inoculation and plant growth (including plant shoot and root weight, leaf area, and total chlorophyll) were higher for well-watered than for water-stressed plants. The growth of AM-treated seedlings was higher than non-AM-treatment regardless of water status. P, K, Zn and Cu contents in AM-treated shoots were greater than those in non-AM shoots under well-watered conditions and drought stress. N and Ca content were higher under drought stress, while AM symbiosis did not affect the Mg content. The contents of soluble sugars, proteins, flavonoid and proline were higher in mycorrhizal than non-mycorrhizal-treated plants under the whole water regime. AM colonization increased the activities of peroxidase enzyme in treatments, but did not affect the catalase activity in shoots and roots under well-watered conditions and drought stress. We conclude that AM colonization improved the drought tolerance of P. vera seedlings by increasing the accumulation of osmotic adjustment compounds, nutritional and antioxidant enzyme activity. It appears that AM formation enhanced the drought tolerance of pistachio plants, which increased host biomass and plant growth.

  4. Effects of submergence in water on seed germination and vigor of the Copaifera lucens (Fabaceae) seedlings

    Institute of Scientific and Technical Information of China (English)

    Daniela Baldez Vidal; Isis Leite Andrade; Marcelo Schramm Mielke

    2014-01-01

    We analyzed the tolerance of Copaifera lucens seeds to sub-mersion in water to assess the use of this species for direct seeding in riparian forest restoration programs. Seeds were submerged in water for 2, 4, 8, 16 and 32 days or not submerged (control = 0 days of submer-gence). For the control and at the end of each period of submersion, germination and seedling vigor tests were carried out. For germination tests, seeds were sown in plastic pots containing sand and kept in labora-tory conditions. The percentage of seed germination, the germination rate and the average germination time were analyzed. For seedlings, total biomass, leaf area, leaf mass per area and leaf area ratio were analyzed. Submersion time drastically affected the dissolved oxygen content and seed germination. Between 4 and 8 days of submersion there was a de-crease from 83.8% to 15.6% in the germination percentage. No seed germination occurred after 16 days of submersion. Although there was a significant decrease in the percentage of seed germination between 4 and 8 days of submersion, seedling vigor was not affected. Seeds of this species were partially tolerant to submersion in water, suggesting that C. lucens is a promising species for direct seeding in riparian forest restora-tion projects.

  5. Hormonal control of endoreduplication in sugar beet (Beta vulgaris L.) seedlings growing in vitro.

    Science.gov (United States)

    Lukaszewska, E; Virden, R; Sliwinska, E

    2012-01-01

    The effect on endoreduplication in sugar beet (Beta vulgaris L.) seedlings of five plant hormones in MS medium, ethylene, 24-epibrassinolide (EBR), gibberellic acid (GA(3) ), kinetin and 1-naphthaleneacetic acid (NAA), as well as a combination of kinetin and NAA at two different concentrations, was studied using flow cytometry. Analyses of DNA content in nuclei of the root, hypocotyl and cotyledons of seedlings growing in vitro were performed during their early development, starting from when the root was 0.5-1.0 cm long until expansion of the first pair of leaves. The proportions of nuclei with different DNA contents were established and the mean C-value calculated. The presence of exogenous plant hormones changed endoreduplication intensity, although to different extents, depending on the organ and developmental stage. Ethylene and NAA stimulated the process, while EBR and kinetin suppressed it and GA did not clearly affect it.

  6. Germination success and seedling development of Argania spinosa under different climatic conditions and browsing intensity.

    Science.gov (United States)

    Zunzunegui, María; Jáuregui, Juan; Ain-Lhout, Fatima; Boutaled, Said; Alvarez-Cansino, Leonor; Esquivias, Maripaz

    2013-01-01

    The present study assesses whether the germination and establishment success of Argania spinosa seeds are affected by the environmental conditions under which the mother plant has grown. Seeds from three populations with different climatic conditions and herbivory intensity were collected and sown in the laboratory after different treatments. Our study suggests that the seed germination process and initial stages of seedling growth are adaptive. Seeds from the population of Agadir with the highest herbivory pressure and high air relative humidity in summer (due to the proximity to the sea) were stimulated by acid treatment, and showed a lower root/stem ratio, which allows them to take advantage of the atmospheric water resources. Seeds from the Mountain population, where the most arid environmental conditions were found, produced early-germinating seeds with the highest root/stem ratio that would facilitate seedling establishment when the harshest environmental conditions appear in summer.

  7. Factors related to establishment of Prosopis caldenia Burk. seedlings in central rangelands of Argentina

    Science.gov (United States)

    de Villalobos, A. E.; Peláez, D. V.; Elia, O. R.

    2005-03-01

    Prosopis caldenia Burk. is one of the woody species that is increasing in abundance due to poor grazing management in the semi-arid phytogeographic region of central Argentina, commonly known as the Caldenal. The objective of this study was to evaluate the effect of herbaceous cover, cattle dung, soil disturbance, and water supply on emergence and survival of P. caldenia seedlings on sites with different grazing histories: (i) a site exposed to long-term continuous grazing by cattle (grazed site), and (ii) a long-term exclosure to domestic livestock (ungrazed site). Removal of grass cover, addition of cattle dung, and water supply enhanced seedling emergence and survival, especially in the grazed site. Results suggest that factors (direct and indirect) associated with prolonged grazing history markedly affect P. caldenia establishment. This in turn alters the grass-woody plant balance, which might reduce the potential capacity of livestock production in the Caldenal.

  8. Quality of tomato seedling in application bioproducts

    OpenAIRE

    BOTEVA, Hriska

    2014-01-01

    The study was performed during the period 2009 - 2011 in the “Maritsa” Vegetable Crops Research Institute, Plovdiv. The effect of organic products Baikal EM – 1У, Bioglobin and Biolan on the quality of seedlings from tomato, variety Yana was studied in unheated glasshouses ro-ON type. Plants were grown on two substrates: peat-perlite substrate and substrate with Lumbrikal. The post-effect of the applied bioproducts on the plant productivity was studied in field conditions. Tomato seeds from Y...

  9. Climate and soil factors influencing seedling recruitment of plant species used for dryland restoration

    Science.gov (United States)

    Muñoz-Rojas, Miriam; Erickson, Todd E.; Martini, Dylan C.; Dixon, Kingsley W.; Merritt, David J.

    2016-06-01

    Land degradation affects 10-20 % of drylands globally. Intensive land use and management, large-scale disturbances such as extractive operations, and global climate change, have contributed to degradation of these systems worldwide. Restoring these damaged environments is critical to improving ecosystem services and functions, conserve biodiversity, and contribute to climate resilience, food security, and landscape sustainability. Here, we present a case study on plant species of the mining intensive semi-arid Pilbara region in Western Australia that examines the effects of climate and soil factors on the restoration of drylands. We analysed the effects of a range of rainfall and temperature scenarios and the use of alternative soil materials on seedling recruitment of key native plant species from this area. Experimental studies were conducted in controlled environment facilities where conditions simulated those found in the Pilbara. Soil from topsoil (T) stockpiles and waste materials (W) from an active mine site were mixed at different proportions (100 % T, 100 % W, and two mixes of topsoil and waste at 50 : 50 and 25 : 75 ratios) and used as growth media. Our results showed that seedling recruitment was highly dependent on soil moisture and emergence was generally higher in the topsoil, which had the highest available water content. In general, responses to the climate scenarios differed significantly among the native species which suggest that future climate scenarios of increasing drought might affect not only seedling recruitment but also diversity and structure of native plant communities. The use of waste materials from mining operations as growth media could be an alternative to the limited topsoil. However, in the early stages of plant establishment successful seedling recruitment can be challenging in the absence of water. These limitations could be overcome by using soil amendments but the cost associated to these solutions at large landscape scales

  10. Evaluation of Promalin to promote growth of young mangosteen seedlings

    Science.gov (United States)

    A major impediment to the development of a mangosteen (Garcinia mangostana L.) industry is the long pre-bearing stage that seedlings take to produce fruits. A field study was conducted to determine the effect of Promalin on the growth of mangosteen seedlings. Promalin was applied as a foliar spray...

  11. Fusarium resistance in Gladiolus: selection in seedling populations

    NARCIS (Netherlands)

    Straathof, Th.P.; Jansen, J.; Roebroeck, E.J.A.; Löffler, H.J.M.

    1997-01-01

    A test to select Fusarium resistant seedlings of Gladiolus is described. Seedlings of 37 populations, obtained from an incomplete diallel between eight parents with different levels of Fusarium resistance, were used. Significant differences in Fusarium infection between and within populations were d

  12. Coumarin pretreatment alleviates salinity stress in wheat seedlings.

    Science.gov (United States)

    Saleh, Ahmed Mahmoud; Madany, M M Y

    2015-03-01

    The potentiality of COU to improve plant tolerance to salinity was investigated. Wheat grains were primed with COU (50 ppm) and then grown under different levels of NaCl (50, 100, 150 mM) for two weeks. COU pretreatment improved the growth of wheat seedling under salinity, relative to COU-untreated seedlings, due to the accumulation of osmolytes such as soluble sugars and proline. Moreover, COU treatment significantly improved K(+)/Na(+) ratio in the shoots of both salt stressed and un-stressed seedlings. However, in the roots, this ratio increased only under non-salinity. In consistent with phenylalanine ammonia lyase (PAL), phenolics and flavonoids were accumulated in COU-pretreated seedlings under the higher doses of salinity, relative to COU-untreated seedlings. COU primed seedlings showed higher content of the coumarin derivative, scopoletin, and salicylic, chlorogenic, syringic, vanillic, gallic and ferulic acids, under both salinity and non-salinity conditions. Salinity stress significantly improved the activity of peroxidase (POD) in COU-pretreated seedlings. However, the effect of COU on the total antioxidant capacity (TAC) was only obtained at the highest dose of NaCl (150 mM). The present results suggest that COU pretreatment could alleviate the adverse effect of salinity on the growth of wheat seedlings through enhancing, at least partly, the osmoregulation process and antioxidant defense system.

  13. Photoreceptive sites in the photocontrol of oat seedling growth

    Directory of Open Access Journals (Sweden)

    Kazimierz Madela

    2014-01-01

    Full Text Available The influence of red light on the growth of coleoptiles and mesocotyles of etiolated and pre-irradiated oat seedlings was investigated. Red light (15 min. applied on whole seedlings stimulated the elongation of coleoptiles and inhibited the growth of mesocotyles both in etiolated and in pre-irradiated plants. Irradiation with red light (2 min of various 2-mm-long regions of etiolated and pre-irradiated oat seedlings was carried out in order to locate their light reception regions. On the basis of growth reactions after such treatment it was found that in completely etiolated seedlings the light reception sites involved in the stimulation of coleoptile elongation and inhibition of mesocotyle growth lie directly above and below the seedling node, whereas in pre-irradiated seedlings, in the top of the seedling. These results point to the existence of different growth photoregulation systems in etiolated and pre-irradiated oat seedlings. The role of phytochrome in these phenomena is discussed.

  14. Control damage by seedling debarking weevil. Technical note No. 271

    Energy Technology Data Exchange (ETDEWEB)

    Eidt, D.C.; Weaver, C.A.A.

    1993-01-01

    Technical note describing a method of controlling the damage to seedlings by the seedling debarking weevil by using nematodes. Information is given on the damage involved, the nematodes to be used, treatment methods, planting procedures, benefits and costs, and results of earlier trials.

  15. Provenances and fertilizer on early growth cedar seedlings

    Directory of Open Access Journals (Sweden)

    Marcio Carlos Navroski

    2016-03-01

    Full Text Available The aim of the study was to evaluate the initial development of different provenances and the influence of base fertilizer and coverage on growth of Cedrela fissilis seedlings. Provenances of seeds were collected in Lapa, PR, Fernandes Pinheiro, PR and Itaara, RS. After germination, the seedlings were transplanted to plastic bags of 500 cm³, filled with commercial substrate. Total height (h, stem diameter (sd, and ratio h/sd seedlings were measured after 150 days of transplanting. Seedlings of Fernandes Pinheiro received basic fertilization after transplantation (0, 2, 4, 6 and 8 g dm-3  Osmocote® and cover (3 and 6 g L-1, respectively, of Peter’s® and urea. The provenance and doses of controlled-release fertilizer influenced early development of Cedrela fissilis seedlings. Itaara provenance showed better seedlings growth. Cedar seedlings showed good growth when incorporated into the substrate 5 g dm-3 Osmocote® and, in addition, applied in topdressing 3 g L-1 of Peter’s®. Urea topdressing is rarely recommended for cedar seedlings.

  16. Evolutionary history and distance dependence control survival of dipterocarp seedlings.

    Science.gov (United States)

    Bagchi, Robert; Press, Malcolm C; Scholes, Julie D

    2010-01-01

    One important hypothesis to explain tree-species coexistence in tropical forests suggests that increased attack by natural enemies near conspecific trees gives locally rare species a competitive advantage. Host ranges of natural enemies generally encompass several closely related plant taxa suggesting that seedlings should also do poorly around adults of closely related species. We investigated the effects of adult Parashorea malaanonan on seedling survival in a Bornean rain forest. Survival of P. malaanonan seedlings was highest at intermediate distances from parent trees while heterospecific seedlings were unaffected by distance. Leaf herbivores did not drive this relationship. Survival of seedlings was lowest for P. malaanonan, and increased with phylogenetic dissimilarity from this species, suggesting that survival of close relatives of common species is reduced. This study suggests that distance dependence contributes to species coexistence and highlights the need for further investigation into the role of shared plant enemies in community dynamics.

  17. Light Regulation of Gibberellins Metabolism in Seedling Development

    Institute of Scientific and Technical Information of China (English)

    Xiao-Ying Zhao; Xu-Hong Yu; Xuan-Ming Liu; Chen-Tao Lin

    2007-01-01

    Light affects many aspects of plant development, including seed germination, stem elongation, and floral initiation. How photoreceptors control photomorphogenic processes is not yet fully understood. Because phytohormones are chemical regulators of plant development, it may not be surprising that light affects,directly or indirectly, cellular levels and signaling processes of various phytohormones, such as auxin,gibberellins (GA), cytokinin, ethylene, abscisic acid (ABA), and brassinosteroids (BR). Among those phytohormones, light regulation of GA metabolism has probably attracted more attention among photobiologists and it is arguably the most extensively studied plant hormone at present with respect to its role in photomorphogenesis. It has become increasingly clear that phytochromes and cryptochromes are the major photoreceptors mediating light regulation of GA homeostasis. This short article attempts to examine some recent developments in our understanding of how light and photoreceptors regulate GA biosynthesis and catabolism during seedling development. It is not our intention to carry out a comprehensive review of the field, and readers are referred to recent review articles for a more complete view of this area of study (Kamiya and Garcia-Martinez 1999; Hedden and Phillips 2000; Garcia-Martinez and Gil 2001; Olszewski et al. 2002; Halliday and Fankhauser 2003; Sun and Gubler 2004).

  18. Screening cotton genotypes for seedling drought tolerance

    Directory of Open Access Journals (Sweden)

    Penna Julio C. Viglioni

    1998-01-01

    Full Text Available The objectives of this study were to adapt a screening method previously used to assess seedling drought tolerance in cereals for use in cotton (Gossypium hirsutum L. and to identify tolerant accessions among a wide range of genotypes. Ninety genotypes were screened in seven growth chamber experiments. Fifteen-day-old seedlings were subjected to four 4-day drought cycles, and plant survival was evaluated after each cycle. Three cycles are probably the minimum required in cotton work. Significant differences (at the 0.05 level or lower among entries were obtained in four of the seven experiments. A "confirmation test" with entries previously evaluated as "tolerant" (high survival and "susceptible" (low survival was run. A number of entries duplicated their earlier performance, but others did not, which indicates the need to reevaluate selections. Germplasms considered tolerant included: `IAC-13-1', `IAC-RM4-SM5', `Minas Sertaneja', `Acala 1517E-1' and `4521'. In general, the technique is simple, though time-consuming, with practical value for screening a large number of genotypes. Results from the screening tests generally agreed with field information. The screening procedure is suitable to select tolerant accessions from among a large number of entries in germplasm collections as a preliminary step in breeding for drought tolerance. This research also demonstrated the need to characterize the internal lack of uniformity in growth chambers to allow for adequate designs of experiments.

  19. Effect of high pressure processing and storage on the free amino acids in seedlings of Brussels sprouts

    DEFF Research Database (Denmark)

    Barba Orellana, Francisco Jose; Poojary, Mahesha Manjunatha; Wang, Jia

    2017-01-01

    The potential of high pressure (HP) to affect the content of free amino acids (FAA) using seedlings of Brussels sprouts as a simple non-chopped vegetable system was examined. Firstly, the effect on FAA composition during growth was assessed and it was found that the composition of total free amino...... acids (TFAA) and individual FAA changed dramatically during growth of the seeds to the seedling at 7 days with the highest content of TFAA. Secondly, 7-day-old seedlings were HP-treated at various pressure levels (200–800 MPa for 3 min at 5 °C). As expected the HP-treatment did not affect the amino......, His, Ile, Lys, Thr, and Val) concluding that the short pressure time (3 min) was insufficient to activate indigenous proteolytic enzymes. Furthermore, changes in the FAA content and composition of HP-treated seedlings during storage (0, 1, 2, and 4 days at 4 ± 2 °C) were evaluated in order to assess...

  20. Functionalized antibiofilm thin coatings based on PLA–PVA microspheres loaded with usnic acid natural compounds fabricated by MAPLE

    Energy Technology Data Exchange (ETDEWEB)

    Grumezescu, Valentina [National Institute for Lasers, Plasma and Radiation Physics, Lasers Department, PO Box MG-36, Bucharest-Magurele, Bucharest (Romania); University Politehnica of Bucharest, Faculty of Applied Chemistry and Materials Science, Department of Science and Engineering of Oxidic Materials and Nanomaterials, Polizu Street no 1-7, 011061 Bucharest (Romania); Socol, Gabriel [National Institute for Lasers, Plasma and Radiation Physics, Lasers Department, PO Box MG-36, Bucharest-Magurele, Bucharest (Romania); Grumezescu, Alexandru Mihai, E-mail: grumezescu@yahoo.com [University Politehnica of Bucharest, Faculty of Applied Chemistry and Materials Science, Department of Science and Engineering of Oxidic Materials and Nanomaterials, Polizu Street no 1-7, 011061 Bucharest (Romania); Holban, Alina Maria [Faculty of Biology, University of Bucharest, Microbiology Immunology Department, Aleea Portocalelor 1-3, Sector 5, 77206 Bucharest (Romania); Ficai, Anton [University Politehnica of Bucharest, Faculty of Applied Chemistry and Materials Science, Department of Science and Engineering of Oxidic Materials and Nanomaterials, Polizu Street no 1-7, 011061 Bucharest (Romania); Truşcǎ, Roxana [S.C. Metav-CD S.A., 31Rosetti Str., 020015 Bucharest (Romania); Bleotu, Coralia [Stefan S Nicolau Institute of Virology, Bucharest (Romania); Balaure, Paul Cǎtǎlin [Department of Organic Chemistry, Faculty of Applied Chemistry and Materials Science, Politehnica Universitiy of Bucharest, Polizu Street no 1-7, 011061 Bucharest (Romania); Cristescu, Rodica [National Institute for Lasers, Plasma and Radiation Physics, Lasers Department, PO Box MG-36, Bucharest-Magurele, Bucharest (Romania); Chifiriuc, Mariana Carmen [Faculty of Biology, University of Bucharest, Microbiology Immunology Department, Aleea Portocalelor 1-3, Sector 5, 77206 Bucharest (Romania)

    2014-05-01

    We report the fabrication of thin coatings of PLA–PVA microspheres loaded with usnic acid by matrix assisted pulsed laser evaporation (MAPLE) onto Ti substrate. The obtained coatings have been physico-chemically characterized by scanning electron microscopy (SEM) and infrared microscopy (IRM). In vitro biological assays have been performed in order to evaluate the influence of fabricated microsphere thin coatings on the Staphylococcus aureus biofilm development as well as their biocompatibility. SEM micrographs have revealed a uniform morphology of thin coatings, while IRM investigations have proved both the homogeneity and functional groups integrity of prepared thin coatings. The obtained microsphere-based thin coatings have proved to be efficient vehicles for usnic acid natural compound with antibiofilm activity, as demonstrated by the inhibitory activity on S. aureus mature biofilm development, opening new perspectives for the prevention and therapy associated to biofilm related infections.

  1. A NEW PULP YIELD PREDICTION METHOD APPLIED TO KRAFT,KRAFT-AQ,POLYSULFIDE AND PSAQ PULPING OF ROCK MAPLE

    Institute of Scientific and Technical Information of China (English)

    Adriaan van Heiningen; Yang Gao; Mehmet Sefik Tunc

    2004-01-01

    Pulp yield has a major impact on the competitiveness of a mill. In order to optimize pulp yield, for example by changing operating conditions, a mill must be able to monitor the yield accurately. In our previous work,a new method was presented for prediction of pulp yield. The method is based on a fundamental relationship derived from the kinetics of the alkaline hydrolysis, peeling and stopping reactions of cellulose and the cellulose mass balance during pulping. In this paper the application of the pulp yield prediction equation for pulping of Rock Maple is investigated. The effect of different operating conditions, such as H-factor, temperature, alkali charge, sulfidity, and the presence of anthraquinone and polysulfide are described.

  2. CdS thin films obtained by thermal treatment of cadmium(II) complex precursor deposited by MAPLE technique

    Energy Technology Data Exchange (ETDEWEB)

    Rotaru, Andrei [INFLPR - National Institute for Laser, Plasma and Radiation Physics, PPAM - Lasers Department, 409 Atomistilor Bvd., Magurele RO-077125, Bucharest (Romania); Mietlarek-Kropidlowska, Anna [Gdansk University of Technology, Chemistry Faculty, 11/12 G. Narutowicza Str., PL-90-233 Gdansk (Poland); Constantinescu, Catalin, E-mail: catalin.constantinescu@inflpr.ro [INFLPR - National Institute for Laser, Plasma and Radiation Physics, PPAM - Lasers Department, 409 Atomistilor Bvd., Magurele RO-077125, Bucharest (Romania); Scarisoreanu, Nicu; Dumitru, Marius [INFLPR - National Institute for Laser, Plasma and Radiation Physics, PPAM - Lasers Department, 409 Atomistilor Bvd., Magurele RO-077125, Bucharest (Romania); Strankowski, Michal [Gdansk University of Technology, Chemistry Faculty, 11/12 G. Narutowicza Str., PL-90-233 Gdansk (Poland); Rotaru, Petre [University of Craiova, Faculty of Physics, 13 A.I. Cuza St., Craiova RO-200585, Dolj (Romania); Ion, Valentin [INFLPR - National Institute for Laser, Plasma and Radiation Physics, PPAM - Lasers Department, 409 Atomistilor Bvd., Magurele RO-077125, Bucharest (Romania); Vasiliu, Cristina [INOE 2000 - National Institute for Optoelectronics, 1 Atomistilor Bvd., Magurele RO-077125, Bucharest (Romania); Becker, Barbara [Gdansk University of Technology, Chemistry Faculty, 11/12 G. Narutowicza Str., PL-90-233 Gdansk (Poland); Dinescu, Maria [INFLPR - National Institute for Laser, Plasma and Radiation Physics, PPAM - Lasers Department, 409 Atomistilor Bvd., Magurele RO-077125, Bucharest (Romania)

    2009-05-15

    Thin films of [Cd{l_brace}SSi(O-Bu{sup t}){sub 3}{r_brace}(S{sub 2}CNEt{sub 2})]{sub 2}, precursor for semiconducting CdS layers, were deposited on silicon substrates by Matrix-Assisted Pulsed Laser Evaporation (MAPLE) technique. Structural analysis of the obtained films by Fourier transform infrared spectroscopy (FTIR) confirmed the viability of the procedure. After the deposition of the coordination complex, the layers are manufactured by appropriate thermal treatment of the system (thin film and substrate), according to the thermal analysis of the compound. Surface morphology of the thin films was investigated by atomic force microscopy (AFM) and spectroscopic-ellipsometry (SE) measurements.

  3. A lousa digital e o uso do maple no cálculo diferencial e integral: potencialidades mediativas

    OpenAIRE

    Kaiber, Carmen; Vecchia, Rodrigo

    2013-01-01

    As potencialidades das Tecnologias de Informação e Comunicação (TIC) para com o processo de ensino e a aprendizagem da Matemática é uma linha de investigação que vem se consolidando dentro do campo da Educação Matemática. Nesse universo é de nosso interesse investigar a relação entre a lousa digital e o uso do software Maple no estudo do Cálculo Diferencial e Integral. O trabalho apresentado visa investigar como o ambiente informático constituído pela presença da lousa digital pode contribuir...

  4. Functionalized antibiofilm thin coatings based on PLA-PVA microspheres loaded with usnic acid natural compounds fabricated by MAPLE

    Science.gov (United States)

    Grumezescu, Valentina; Socol, Gabriel; Grumezescu, Alexandru Mihai; Holban, Alina Maria; Ficai, Anton; Truşcǎ, Roxana; Bleotu, Coralia; Balaure, Paul Cǎtǎlin; Cristescu, Rodica; Chifiriuc, Mariana Carmen

    2014-05-01

    We report the fabrication of thin coatings of PLA-PVA microspheres loaded with usnic acid by matrix assisted pulsed laser evaporation (MAPLE) onto Ti substrate. The obtained coatings have been physico-chemically characterized by scanning electron microscopy (SEM) and infrared microscopy (IRM). In vitro biological assays have been performed in order to evaluate the influence of fabricated microsphere thin coatings on the Staphylococcus aureus biofilm development as well as their biocompatibility. SEM micrographs have revealed a uniform morphology of thin coatings, while IRM investigations have proved both the homogeneity and functional groups integrity of prepared thin coatings. The obtained microsphere-based thin coatings have proved to be efficient vehicles for usnic acid natural compound with antibiofilm activity, as demonstrated by the inhibitory activity on S. aureus mature biofilm development, opening new perspectives for the prevention and therapy associated to biofilm related infections.

  5. Allelopathy of Sage and White Wormwood on Purslane Germination and Seedling Growth

    Directory of Open Access Journals (Sweden)

    Alireza PIRZAD

    2010-09-01

    Full Text Available A bioassay run was carried out in the incubator to evaluate possible allelopathic effects of water extracts of sage and white wormwood on germination and seedling growth of purslane. Results showed that the type of extract and its concentration (0, 5, 10, 15 and 20% significantly influenced final germination percentage, germination rate and index, root and shoot length, root/shoot ratio, fresh and dry weight of seedling of purslane. The interaction between these two experimental factors was always significant, producing different results according to the different combination levels. The statistical comparison of means indicated that the maximum germination percentage and germination rate (respectively 68% and 11.4% d-1 were obtained from the untreated control (0% extract, while the lowest values for the same two characters occurred with 15% of sage (respectively 45% and 6.4% d-1 and 20% of white wormwood (38% and 7.5% d-1. Concerning germination indexes, the highest (55 and the lowest (32 values were observed respectively on the control and with 15% of sage extract or 20% of white wormwood extract. The longest (4.5 cm and the shortest (1.3 cm root of purslane were obtained with 5% of white wormwood and 20% of sage extracts, respectively. Changes in shoot length with sage and white wormwood extracts were similar to those in root length, even though shoot length was less affected by the concentration of extracts. Root and shoot length changes brought to maximum (22.0 and minimum (8.9 values for the root/shoot length ratio, respectively with 5% of white wormwood and 20% of sage extracts. The maximum fresh (2.111 g and dry (0.338 g seedling weight of purslane were obtained from untreated control, producing the same seedling weight with 5% of sage, 5 and 10% of white wormwood extract. While the minimum fresh (0.692 g and dry (0.111 g seedling weight were obtained from 15% of white wormwood extract, so that there is no significant differences between

  6. Impacts of Climate Change on the Timing of the Production Season of Maple Syrup in Eastern Canada.

    Directory of Open Access Journals (Sweden)

    Daniel Houle

    Full Text Available Maple syrup production is an important economic activity in north-eastern North-America. The beginning and length of the production season is linked to daily variation in temperature. There are increasing concerns about the potential impact of climatic change on this industry. Here, we used weekly data of syrup yield for the 1999-2011 period from 121 maple stands in 11 regions of Québec (Canada to predict how the period of production may be impacted by climate warming. The date at which the production begins is highly variable between years with an average range of 36 days among the regions. However, the average start date for a given region, which ranged from Julian day 65 to 83, was highly predictable (r2 = 0.88 using the average temperature from January to April (TJ-A. A logistic model predicting the weekly presence or absence of production was also developed. Using the inputs of 77 future climate scenarios issued from global models, projections of future production timing were made based on average TJ-A and on the logistic model. The projections of both approaches were in very good agreement and suggest that the sap season will be displaced to occur 15-19 days earlier on average in the 2080-2100 period. The data also show that the displacement in time will not be accompanied by a greater between years variability in the beginning of the season. However, in the southern part of Québec, very short periods of syrup production due to unfavourable conditions in the spring will occur more frequently in the future although their absolute frequencies will remain low.

  7. Design and experiment on transplanter pot seedling disk conveying and positioning control system%苗盘钵苗自动识别及控制装置的设计与试验

    Institute of Scientific and Technical Information of China (English)

    吴俭敏; 张小超; 金鑫; 刘忠军; 朱立成; 孙星; 邹卓然; 刘邦司

    2015-01-01

    identification rate was improved. The system was only carried out in the laboratory test, but field test has not yet performed. In field operation, some factor may affect the automatic recognition and seedling fetching device reliability and stability, such as vibration of machines, interference of the sensor by sunshine outdoor. These need further test and examination. More field experiment needs to be tested for the influences of machine vibration and sunlight to the photoelectric sensor.

  8. Hunting alters seedling functional trait composition in a Neotropical forest.

    Science.gov (United States)

    Kurten, Erin L; Wright, S Joseph; Carson, Walter P

    2015-07-01

    Defaunation alters trophic interactions between plants and vertebrates, whichmay disrupt trophic cascades, thereby favoring a subset of plant species and reducing diversity. If particular functional traits characterize the favored plant species,.then defaunation may alter community-wide patterns of functional trait composition. Changes in plant functional traits occurring with defaunation may help identify the species interactions affected by defaunation and the potential for other cascading effects of defaunation. We tested the hypotheses that defaunation would (1) disrupt seed dispersal, thereby favoring species whose dispersal agents are not affected (e.g., small birds, bats, and abiotic agents), (2) reduce seed predation, thereby favoring larger-seeded species, and (3) reduce herbivory, thereby favoring species with lower leaf mass per area (LMA), leaf toughness, and wood density. We examined how these six traits responded to vertebrate defaunation caused by hunters or by experimental exclosures among more than-30 000 woody seedlings in a lowland tropical moist forest. Exclosures reduced terrestrial frugivores, granivores, and herbivores, while hunters also reduced volant and arboreal frugivores and granivores. The comparison of exclosures and hunting allowed us to parse the impacts of arboreal and volant species (reduced by hunters only) and terrestrial species (reduced by both hunters and exclosures). The loss of terrestrial vertebrates alone had limited effects on plant trait composition. The additional loss of volant and arboreal vertebrates caused significant shifts in plant species composition towards communities with more species dispersed abiotically, including lianas and low wood-density tree species, and fewer species dispersed by large vertebrates. In contrast to previous studies, community seed mass did not decline significantly in hunted sites. Our exclosure results suggest this is because reducing seed predators disproportionately benefits large

  9. Effects of open-field experimental warming on the growth of two-year-old Pinus densiflora and Abies holophylla seedlings

    Science.gov (United States)

    Han, S.; Son, Y.; Lee, S.; Jo, W.; Yoon, T.; Park, C.; Ko, S.; Kim, J.; Han, S.; Jung, Y.

    2012-12-01

    Temperature increase due to climate change is expected to affect tree growth and distribution [Way and Oren, 2010]. The responses of trees to warming vary with tree species, ontogenic stages, tree life forms, and biomes. Especially, seedling stage is a vulnerable period for tree survival and competition [Saxe et al., 2007] and thus research on effects of temperature increase on seedling stage is needed. We aimed to examine the responses of coniferous seedlings to future temperature increase by conducting an open-field warming experiment. An experimental warming set-up using infra-red heater was built in 2011 and the temperature in warming plots has been regulated to 3°C higher than that of control plots constantly. The seeds of Pinus densiflora and Abies holophylla were planted in each 1 m × 1 m plot (n=3) in April, 2012. Seedling growth, root collar diameter (RCD) and height of 45 individuals of each plot were measured in June and July, 2012. The survival rate of seedlings was also measured. Survival rate of P. densiflora was lower in warming plots (93.3%) than in control plots (100.0%, pdensiflora seedlings were not significantly different between control and warming plots, however, height of A. holophylla was significantly higher in warming plots in June and July (p<0.01). Comparatively, RCD of A. holophylla was only higher in control plots in June. While there is still a lack of case studies on the growth of seedlings under experimental warming, a few studies reported increased seedling growth [Yin et al., 2008] or and no difference [Han et al., 2009] in warming plots. Different responses of seedling growth between two species of the current study might be derived from species-specific acclimation to temperature increase and/or other limiting factors [Way and Oren, 2010]. This result is, to our knowledge, unprecedented and will contribute to the knowledge of species-specific growth response of tree species and to development of model predicting species

  10. Denied density-dependent seedling recruitment in a fragmented forest does not decrease seedling diversity El denegado reclutamiento denso-dependiente de plántulas en un bosque fragmentado no disminuye la diversidad de plántulas

    Directory of Open Access Journals (Sweden)

    CARLOS E VALDIVIA

    2011-06-01

    Full Text Available Negative density-dependent relationships in plant communities are currently claimed as an important mechanism for the maintenance of plant diversity. However, anthropogenic perturbations such as forest fragmentation might modify such relationships. We evaluated density-dependent relationships between seed and seedling abundance of a tree assemblage in a fragmented forest for estimating seed-to-seedling transitions and their effects on seedling richness. In continuous forest, two out of four and one out of four species presented significant or a tendency to exhibit negative seedling recruitment which is in agreement with other temperate and tropical forests. In forest fragments (1-6 ha, however, this relationship was uncoupled. Seedling richness and diversity, assessed through Shannon-Wiener Index, did not differ between both types of sites. Therefore, forest fragmentation negatively affected seedling recruitment by uncoupling seed-to-seedling transitions, but not by diminishing seedling diversity. This leads to considering the role of density-dependent relationships for the maintenance of plant diversity in communities and claims for including forest fragments into conservation programmes.Las relaciones denso-dependientes negativas en las comunidades vegetales son actualmente señaladas como un importante mecanismo para la mantención de la diversidad de plantas. Sin embargo, las perturbaciones antropogénicas como la fragmentación del bosque podrían modificar este tipo de relaciones. Evaluamos las relaciones denso-dependientes entre las abundancias de semillas y plántulas en un ensamble de árboles en un bosque fragmentado para estimar las transiciones de semillas a plántulas y sus efectos sobre la riqueza de plántulas. En el bosque continuo tres de cuatro especies presentaron reclutamientos de plántulas negativos, lo cual se condice con otros bosques templados y tropicales. En los fragmentos de bosque (1-6 ha, no obstante, estas

  11. Microencapsulation of seed-coating tebuconazole and its effects on physiology and biochemistry of maize seedlings.

    Science.gov (United States)

    Yang, Daibin; Wang, Na; Yan, Xiaojing; Shi, Jie; Zhang, Min; Wang, Zhenying; Yuan, Huizhu

    2014-02-01

    Tebuconazole is a triazole systemic fungicide that is commonly used to treat fungal pathogens of crops, but at high doses can reduce seed germination. Seeds with microcapsulated tebuconazole were investigated to determine effects of this method on maize seedlings and the bioefficacy against maize head smut (Sphacelotheca reiliana). The ethyl cellulose (EC)-based microcapsules had encapsulation efficiency of 90.6%, and average size of 1.6 μm. A release kinetic study revealed that tebuconazole release from EC-based microcapsules fits the model (Mt/Mz=kt(n)+C). Glasshouse studies indicated that maize seedling emergence and growth were negatively affected in an exponential manner as predicted by model Y=A+B×e((-x/k)). However, microencapsulation could induce tebuconazole's growth promoting effects by increasing emergence, shoot fresh weight, root fresh weight, carotenoid and chlorophyll content. Phytohormone analysis indicated the beneficial effects of microencapsulated tebuconazole were due to the sustained release of tebuconazole that appeared to influence the balance of phytohormones in maize seedlings. Contrary to conventional tebuconazole, microencapsulated seed-coated tebuconazole can lead to slightly increased gibberellins (GA) level and disappearance of abscisic acid (ABA) accumulation in maize. In addition, microcapsule formulation of tebuconazole was found to provide better protection against maize head smut when compared to conventional formulation.

  12. Removal of a combination of endocrine disruptors from aqueous systems by seedlings of radish and ryegrass.

    Science.gov (United States)

    Gattullo, C Eliana; Cunha, Bruno Barboza; Rosa, André H; Loffredo, Elisabetta

    2013-01-01

    Endocrine disruptors (EDs) are widespread in the environment, especially aquatic systems, and cause dangerous effects on wildlife and humans. This work was aimed to assess the capacity of radish (Raphanus sativus L.) and ryegrass (Lolium perenne L.) seedlings to tolerate and remove two combinations of EDs containing bisphenol A (BPA), 17alpha-ethynilestradiol (EE2), and linuron from four aqueous media: distilled water, a solution of natural organic matter (NOM), a lake water and a river water. Seeds of the two species were germinated in each contaminated medium and, at the end of germination, the seedling growth was evaluated by biometric measurements and residual EDs were quantified by chromatographic analysis. Biometric measurements revealed that the phytotoxicity of the two combinations of EDs depended on the medium used. Radish showed a discrete tolerance in distilled water and lake water but was inhibited in the solution of NOM and river water. Ryegrass was negatively affected mainly in river water. The concentration of each ED appeared significantly reduced in all media in the presence of seedlings of both species, but not in the blanks without plants. In 5 days, radish removed up to 88% of BPA, 100% of EE2 and 42% of linuron, and in 6 days ryegrass removed up to 92% of BPA, 74% of EE2 and 16% of linuron. The considerable removal capacity of radish and ryegrass in all media tested encourages the use of phytoremediation to remove EDs from waters.

  13. Asymmetric distribution of glucose and indole-3-acetyl-myo-inositol in geostimulated Zea mays seedlings

    Science.gov (United States)

    Momonoki, Y. S.; Bandurski, R. S. (Principal Investigator)

    1988-01-01

    Indole-3-acetyl-myo-inositol occurs in both the kernel and vegetative shoot of germinating Zea mays seedlings. The effect of a gravitational stimulus on the transport of [3H]-5-indole-3-acetyl-myo-inositol and [U-14C]-D-glucose from the kernel to the seedling shoot was studied. Both labeled glucose and labeled indole-3-acetyl-myo-inositol become asymmetrically distributed in the mesocotyl cortex of the shoot with more radioactivity occurring in the bottom half of a horizontally placed seedling. Asymmetric distribution of [3H]indole-3-acetic acid, derived from the applied [3H]indole-3-acetyl-myo-inositol, occurred more rapidly than distribution of total 3H-radioactivity. These findings demonstrate that the gravitational stimulus can induce an asymmetric distribution of substances being transported from kernel to shoot. They also indicate that, in addition to the transport asymmetry, gravity affects the steady state amount of indole-3-acetic acid derived from indole-3-acetyl-myo-inositol.

  14. Differential expression of superoxide dismutase genes in aphid-stressed maize (Zea mays L.) seedlings.

    Science.gov (United States)

    Sytykiewicz, Hubert

    2014-01-01

    The aim of this study was to compare the expression patterns of superoxide dismutase genes (sod2, sod3.4, sod9 and sodB) in seedling leaves of the Zea mays L. Tasty Sweet (susceptible) and Ambrozja (relatively resistant) cultivars infested with one of two hemipteran species, namely monophagous Sitobion avenae F. (grain aphid) or oligophagous Rhopalosiphum padi L. (bird cherry-oat aphid). Secondarily, aphid-elicited alternations in the antioxidative capacity towards DPPH (1,1-diphenyl-2-picrylhydrazyl) radical in insect-stressed plants were evaluated. Comprehensive comparison of expression profiles of the four sod genes showed that both insect species evoked significant upregulation of three genes sod2, sod3.4 and sod9). However, aphid infestation affected non-significant fluctuations in expression of sodB gene in seedlings of both maize genotypes. The highest levels of transcript accumulation occurred at 8 h (sod2 and sod3.4) or 24 h (sod9) post-infestation, and aphid-induced changes in the expression of sod genes were more dramatic in the Ambrozja cultivar than in the Tasty Sweet variety. Furthermore, bird cherry-oat aphid colonization had a more substantial impact on levels of DPPH radical scavenging activity in infested host seedlings than grain aphid colonization. Additionally, Ambrozja plants infested by either hemipteran species showed markedly lower antioxidative capacity compared with attacked Tasty Sweet plants.

  15. Production of gherkin seedlings in coconut fiber fertirrigated with different nutrient solutions

    Directory of Open Access Journals (Sweden)

    Francisco de Assis de Oliveira

    Full Text Available ABSTRACT Seedling quality is a key factor to achieve success in vegetable production. The present work aimed to evaluate the production of gherkin seedlings in substrate of coconut fiber fertirrigated with different concentrations of nutrients. The experimental design was completely randomized in a 3 × 5 factorial with four replications. The treatments consisted of combinations of three cultivars of gherkin (Do Norte, Liso de Calcutá, e Liso Gibão with five concentrations of nutrients in the solution (0, 25, 50, 75, and 100%. The nutrient solution, considered standard, matches the recommended solution for melon in hydroponic systems. We evaluated the variables: chlorophyll index, shoot length, number of leaves, stem diameter, main root length, dry weight of leaves, roots, and stem, mass of total dry matter, leaf area, specific leaf area, and leaf area ratio. All variables were affected by the ionic concentration in nutrient solutions. The use of coconut fiber in the production of gherkin seedlings is more efficient with nutrient solutions in concentrations ranging from 75 to 100% of the recommended solution for melon cultivation.

  16. Differential expression of superoxide dismutase genes in aphid-stressed maize (Zea mays L. seedlings.

    Directory of Open Access Journals (Sweden)

    Hubert Sytykiewicz

    Full Text Available The aim of this study was to compare the expression patterns of superoxide dismutase genes (sod2, sod3.4, sod9 and sodB in seedling leaves of the Zea mays L. Tasty Sweet (susceptible and Ambrozja (relatively resistant cultivars infested with one of two hemipteran species, namely monophagous Sitobion avenae F. (grain aphid or oligophagous Rhopalosiphum padi L. (bird cherry-oat aphid. Secondarily, aphid-elicited alternations in the antioxidative capacity towards DPPH (1,1-diphenyl-2-picrylhydrazyl radical in insect-stressed plants were evaluated. Comprehensive comparison of expression profiles of the four sod genes showed that both insect species evoked significant upregulation of three genes sod2, sod3.4 and sod9. However, aphid infestation affected non-significant fluctuations in expression of sodB gene in seedlings of both maize genotypes. The highest levels of transcript accumulation occurred at 8 h (sod2 and sod3.4 or 24 h (sod9 post-infestation, and aphid-induced changes in the expression of sod genes were more dramatic in the Ambrozja cultivar than in the Tasty Sweet variety. Furthermore, bird cherry-oat aphid colonization had a more substantial impact on levels of DPPH radical scavenging activity in infested host seedlings than grain aphid colonization. Additionally, Ambrozja plants infested by either hemipteran species showed markedly lower antioxidative capacity compared with attacked Tasty Sweet plants.

  17. Pretreating dogwood seedlings with simulated acidic precipitation increases dogwood anthracnose symptoms in greenhouse-laboratory trials

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, R.L.; Knighten, J. (USDA Forest Service, Resistance Screening Center, Asheville, NC (United States)); Berrange, P.; Lawton, K.A. (USDA Forest Service, Center for Forest Environmental Studies, Dry Branch, GA (United States)); Britton, K.O. (USDA Forest Service, Southeastern Forest Experiment Station, Athens, GA (United States))

    1993-01-01

    Dogwood anthracnose is the most damaging disease of flowering dogwood (Cornus florida L.) in a large part of the tree's natural range. It is caused by Discula destructiva infection. Previous attempts to inoculate C. florida to produce anthracnose symptoms have met with limited success except when the leaves were pretreated with acidic water, suggesting that acidic precipitation may predispose dogwoods to the disease. This hypothesis was tested in two greenhouse-laboratory studies in which year-old C. florida seedlings were randomly assigned to four treatments of simulated rain (pH 2.5, 3.5, 4.5, and 5.5) in 1989 and 1990. After 10 applications over a 42-d period, the seedlings were moved to a temperature-controlled laboratory, placed in plastic bags, humidified, and sprayed with a spore suspension of five D. destructiva isolates. About 30 d layter, the seedlings were examined for the percentage of leaves exhibiting anthracnose symptoms and disease severity on affected leaves. Both trials showed that as the acidity of the simulated rain increased, the incidence and severity of anthracnose leaf symptoms increased. The 1989 study included a soil lime treatment that showed the same trend but the overall occurrence and severity of symptoms was higher. 17 refs., 5 tabs.

  18. Characterization of nutrient deficiency in Hancornia speciosa Gomes seedlings by omitting micronutrients from the nutrient solution

    Directory of Open Access Journals (Sweden)

    Layara Alexandre Bessa

    2013-06-01

    Full Text Available Hancornia speciosa Gomes (Mangaba tree is a fruit tree belonging to the Apocynaceae family and is native to Brazil. The production of seedlings of this species is limited by a lack of technical and nutritional expertise. To address this deficiency, this study aimed to characterize the visual symptoms of micronutrient deficiency and to assess growth and leaf nutrient accumulation in H. speciosa seedlings supplied with nutrient solutions that lack individual micronutrients. H. speciosa plants were grown in nutrient solution in a greenhouse according to a randomized block design, with four replicates. The treatments consisted of a group receiving complete nutrient solution and groups treated with a nutrient solution lacking one of the following micronutrients: boron (B, copper (Cu, iron (Fe, manganese (Mn, zinc (Zn, and molybdenum (Mo. The visual symptoms of nutrient deficiency were generally easy to characterize. Dry matter production was affected by the omission of micronutrients, and the treatment lacking Fe most limited the stem length, stem diameter, root length, and number of leaves in H. speciosa seedlings as well as the dry weight of leaves, the total dry weight, and the relative growth in H. speciosa plants. The micronutrient contents of H. speciosa leaves from plants receiving the complete nutrient solution treatment were, in decreasing order, Fe>Mn>Cu>Zn>B.

  19. Effects of "short" photoperiods on seedling growth of Pinus brutia.

    Science.gov (United States)

    Iakovoglou, V; Radoglou, K; K