WorldWideScience

Sample records for shooting range soil

  1. Lead Pollution of Shooting Range Soils

    African Journals Online (AJOL)

    NICOLAAS

    range. Most of the shooting range soils contained high levels of Pb in the range above 2000 mg kg–1 far exceeding the United States ... N. Sehube, R. Kelebemang, O. Totolo, M. Laetsang, O. Kamwi and P. Dinake,. 21 ..... Eng. Sci., 1999, 16,.

  2. Lead pollution of shooting range soils | Sehube | South African ...

    African Journals Online (AJOL)

    Atotal of eight military shooting ranges were used for this study. Soil samples were collected at each of the eight shooting ranges at the berm, target line, 50 and 100 m from berm. In all of the shooting ranges investigated the highest total lead (Pb) concentrations were found in the bermsoils. Elevated Pb concentrations of 38 ...

  3. Soil pollution at outdoor shooting ranges: Health effects, bioavailability and best management practices.

    Science.gov (United States)

    Fayiga, A O; Saha, U K

    2016-09-01

    The total lead (Pb) concentrations of the surface soil, sub surface soil, vegetation and surface waters of outdoor shooting ranges are extremely high and above regulatory limits. Lead is dangerous at high concentrations and can cause a variety of serious health problems. Shooters and range workers are exposed to lead dust and can even take Pb dust home to their families while some animals around the shooting range can ingest the Pb bullets. The toxicity of Pb depends on its bioavailability which has been determined to be influenced greatly by the geochemical properties of each site. The bioavailability of Pb in shooting ranges has been found to be higher than other metal contaminated soils probably because of its very low residual Pb (soil, migration of Pb within shooting ranges and offsite has been reported in literature. Best management practices to reduce mobility of Pb in shooting ranges involve an integrated Pb management program which has been described in the paper. The adoption of the non-toxic "green bullet" which has been developed to replace Pb bullets may reduce or prevent environmental pollution at shooting ranges. However, the contaminated soil resulting from decades of operation of several shooting ranges still needs to be restored to its natural state. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Stabilizing lead bullets in shooting range soil by phosphate-based surface coating

    Directory of Open Access Journals (Sweden)

    Bin Hua

    2016-08-01

    Full Text Available Soil lead (Pb is well known as a threat to human health and ecosystem. Although relatively insoluble, lead bullets in shooting range soil can be readily released into soluble forms through natural weathering processes and thus pose significant human and environmental risks. In this study, laboratory experiments were conducted to investigate if the Pb bullets in shooting range soil can be stabilized through surface coating of phosphate-based materials. Results indicated that FePO4 or AlPO4 coatings, insoluble metal phosphates, have been successfully formed on the surface of the Pb bullets. The EPA Toxicity Characteristic Leaching Procedure (TCLP test showed that FePO4 or AlPO4 surface coating would effectively reduce the Pb solubility or leachability of the bullets. The surface coating under pH of <5.5 for 7 days could achieve 92–100% reduction, with 85–98% by FePO4 coating and 77–98% by AlPO4 coating as compared with the non-coating. Leachable Pb concentration in the contaminated shooting range soil was reduced by 85–98% or 77–98% as a result of the FePO4 or AlPO4 solution treatment. This study demonstrated that the FePO4 or AlPO4–based surface coating on lead bullets can effectively inhibit the Pb weathering and significantly reduce the Pb release from soil through in situ chemical stabilization, which could be potentially applicable as a cost-effective and environmental-sound technology for the remediation of Pb-contaminated shooting range soil.

  5. Immobilization of lead in shooting range soil using biochar from ...

    African Journals Online (AJOL)

    Spent mushroom substrate (SMS) was pyrolyzed at 450°C for 2 hours and characterized using elemental analyzer and Boehm titration. Shooting range soil was incubated with 2.5% w/w and 5.0% w/w of SMSB for four weeks and the soil were characterized on the elemental composition, pH, electric conductivity (EC) and ...

  6. Can the soil fauna of boreal forests recover from lead-derived stress in a shooting range area?

    Science.gov (United States)

    Selonen, Salla; Liiri, Mira; Setälä, Heikki

    2014-04-01

    The responses of soil faunal communities to lead (Pb) contamination in a shooting range area and the recovery of these fauna after range abandonment were studied by comparing the communities at an active shotgun shooting range, an abandoned shooting range, and a control site, locating in the same forest. Despite the similar overall Pb pellet load at the shooting ranges, reaching up to 4 kg m(-2), Pb concentrations in the top soil of the abandoned range has decreased due to the accumulation of detritus on the soil surface. As a consequence, soil animal communities were shown to recover from Pb-related disturbances by utilizing the less contaminated soil layer. Microarthropods showed the clearest signs of recovery, their numbers and community composition being close to those detected at the control site. However, in the deepest organic soil layer, the negative effects of Pb were more pronounced at the abandoned than at the active shooting range, which was detected as altered microarthropod and nematode community structures, reduced abundances of several microarthropod taxa, and the total absence of enchytraeid worms. Thus, although the accumulation of fresh litter on soil surface can promote the recovery of decomposer communities in the top soil, the gradual release of Pb from corroding pellets may pose a long-lasting risk for decomposer taxa deeper in the soil.

  7. Immobilization of lead in shooting range soils by means of cement, quicklime, and phosphate amendments.

    Science.gov (United States)

    Cao, Xinde; Dermatas, Dimitris; Xu, Xuanfeng; Shen, Gang

    2008-03-01

    Lead (Pb) contamination at shooting range sites is increasingly under environmental concern. Controlling Pb leachability from shooting range soil media is an important step to minimize Pb exposure to the surrounding environment. This study investigated stabilization of Pb in shooting range soils treated with cement, quicklime, and phosphate. Two soils were used and collected from two shooting ranges, referred to as SR1 and SR2. The treatment additives were applied to the soils at rates from 2.5% to 10% (w/w). The effectiveness of each treatment was evaluated by Pb (w/w). The effectiveness of each treatment was evaluated by Pb leachability, measured by the Toxicity Characteristic Leaching Procedure (TCLP). The possible mechanisms for Pb immobilization were elucidated using X-ray powder diffraction (XRPD). Cement and quicklime treatments were effective in immobilizing Pb in SR1 soil, with reduction of Pb concentration in TCLP leachate (TCLP-Pb) to be below the U.S. EPA non-hazardous regulatory limit of 5 mg L(-1) at application rates of > or =5% and 28-d incubation. By contrast, cement and quicklime amendments were less effective for Pb stabilization in SR2 soil because the TCLP-Pb levels in the treated soil were still higher than the limit of 5 mg L(-1) at all application rates, although they were significantly reduced in comparison with the untreated soil. Phosphate application was most effective in reducing Pb leach ing in both soils. Even at an application rate as low as 5% and 1-d incubation, phosphate could reduce TCLP-Pb to be below the limit of 5 mg L(-1) in both soils. Immobilization of Pb in the SR1 soil amended with cement and quicklime was attributed to the formation of pozzolanic minerals (e.g., calcium silicate hydrate C-S-H and ettringite) that could encapsulate soil Pb. The pozzolanic reaction was limited in the SR2 soil upon the application of cement and quicklime. Reduction of the TCLP-Pb might result from complexation of Pb on the surface of the

  8. The effects of heavy metal contamination on the soil arthropod community of a shooting range

    International Nuclear Information System (INIS)

    Migliorini, Massimo; Pigino, Gaia; Bianchi, Nicola; Bernini, Fabio; Leonzio, Claudio

    2004-01-01

    Soils in clay pigeon shooting ranges can be seriously contaminated by heavy metals. The pellets contained in ammunition are composed of Pb, Sb, Ni, Zn, Mn and Cu. The total concentrations of these metals in soils, and the effects of their increasing levels on the arthropod community were investigated at seven sampling sites in a clay pigeon shooting range and compared with two controls. Research revealed that the spatial distribution of Pb and Sb contamination in the shot-fall area was strongly correlated with the flight path of the pellets. Ordination obtained through Redundance Analysis showed that Collembola, Protura and Diplura were positively correlated with major detected contaminants (Pb, Sb), while Symphyla showed a negative correlation with these pollutants. Determination of the soluble lead fraction in soil, and of its bioaccumulation in the saprophagous Armadillidium sordidum (Isopoda) and the predator Ocypus olens (Coleoptera), showed that a significant portion of metallic Pb from spent pellets is bioavailable in the soil and can be bioaccumulated by edaphic organisms, entering the soil trophic network, but without biomagnification. - Significant relationships were found between lead accumulation in soil from a shooting range and inhabiting arthropod communities

  9. Plant uptake and availability of antimony, lead, copper and zinc in oxic and reduced shooting range soil.

    Science.gov (United States)

    Hockmann, Kerstin; Tandy, Susan; Studer, Björn; Evangelou, Michael W H; Schulin, Rainer

    2018-03-19

    Shooting ranges polluted by antimony (Sb), lead (Pb), copper (Cu) and zinc (Zn) are used for animal grazing, thus pose a risk of contaminants entering the food chain. Many of these sites are subject to waterlogging of poorly drained soils. Using field lysimeter experiments, we compared Sb, Pb, Cu and Zn uptake by four common pasture plant species (Lolium perenne, Trifolium repens, Plantago lanceolata and Rumex obtusifolius) growing on a calcareous shooting range soil under waterlogged and drained conditions. To monitor seasonal trends, the same plants were collected at three times over the growing season. Additionally, variations in soil solution concentrations were monitored at three depths over the experiment. Under reducing conditions, soluble Sb concentrations dropped from ∼50 μg L -1 to ∼10 μg L -1 , which was attributed to the reduction of Sb(V) to Sb(III) and the higher retention of the trivalent species by the soil matrix. Shoot Sb concentrations differed by a factor of 60 between plant species, but remained at levels <0.3 μg g -1 . Despite the difference in soil solution concentrations between treatments, total Sb accumulation in shoots for plants collected on the waterlogged soil did not change, suggesting that Sb(III) was much more available for plant uptake than Sb(V), as only 10% of the total Sb was present as Sb(III). In contrast to Sb, Pb, Cu and Zn soil solution concentrations remained unaffected by waterlogging, and shoot concentrations were significantly higher in the drained treatment for many plant species. Although showing an increasing trend over the season, shoot metal concentrations generally remained below regulatory values for fodder plants (40 μg g -1  Pb, 150 μg g -1 Zn, 15-35 μg g -1 Cu), indicating a low risk of contaminant transfer into the food chain under both oxic and anoxic conditions for the type of shooting range soil investigated in this study. Copyright © 2018 Elsevier Ltd. All rights

  10. Lead pollution of soil and groundwater in clay-pigeon shooting ranges

    International Nuclear Information System (INIS)

    Hahn, R.

    1990-01-01

    Within the framework of the exemplary investigation of soil and groundwater pollution with lead on clay-pigeon shooting ranges, three facilities were sampled. The analyses for depth distribution in the main area of the ammunition deposition showed that the dissolved lead amounts are as a rule smaller than the limiting value of the Sewage Sludge Regulation (100 mg/kg). In two groundwater samples, no lead could be found. Considerable amounts of small lead balls are found on the soil surface, but only a very small part appears to be washed out and adsorbed by the soil matrix. (orig.) [de

  11. Immobilization of lead in a Korean military shooting range soil using eggshell waste: An integrated mechanistic approach

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, Mahtab [Department of Biological Environment, Kangwon National University, Chuncheon 200-701 (Korea, Republic of); Hashimoto, Yohey [Department of Bioresource Science, Mie University, 1577 Kurima-machiya, Mie 514-8507 (Japan); Moon, Deok Hyun [Department of Environmental Engineering, Chosun University, Gwangju 501-759 (Korea, Republic of); Lee, Sang Soo, E-mail: sslee97@kangwon.ac.kr [Department of Biological Environment, Kangwon National University, Chuncheon 200-701 (Korea, Republic of); Ok, Yong Sik, E-mail: soilok@kangwon.ac.kr [Department of Biological Environment, Kangwon National University, Chuncheon 200-701 (Korea, Republic of)

    2012-03-30

    Highlights: Black-Right-Pointing-Pointer Eggshell and calcined eggshell immobilized Pb in the shooting range soil. Black-Right-Pointing-Pointer Calcined eggshell was more effective on Pb immobilization compared to eggshell. Black-Right-Pointing-Pointer Exchangeable Pb fractions were transformed to carbonate bound fractions. Black-Right-Pointing-Pointer Calcined eggshell stabilized Pb by enwrapping into calcium silicate hydrate. Black-Right-Pointing-Pointer Soil Pb toxicity can be reduced by applying eggshell and calcined eggshell. - Abstract: This study evaluated the effectiveness of eggshell and calcined eggshell on lead (Pb) immobilization in a shooting range soil. Destructive and non-destructive analytical techniques were employed to determine the mechanism of Pb immobilization. The 5% additions of eggshell and calcined eggshell significantly decreased the TCLP-Pb concentration by 68.8% due mainly to increasing soil pH. Eggshell and calcined-eggshell amendments decreased the exchangeable Pb fraction to {approx}1% of the total Pb in the soil, while the carbonate-associated Pb fraction was increased to 40.0-47.1% at >15% application rates. The thermodynamic modeling on Pb speciation in the soil solution predicted the precipitation of Pb-hydroxide [Pb(OH){sub 2}] in soils amended with eggshell and calcined eggshell. The SEM-EDS, XAFS and elemental dot mapping revealed that Pb in soil amended with calcined eggshell was associated with Si and Ca, and may be immobilized by entrapping into calcium-silicate-hydrate. Comparatively, in the soil amended with eggshell, Pb was immobilized via formation of Pb-hydroxide or lanarkite [Pb{sub 2}O(SO{sub 4})]. Applications of amendments increased activities of alkaline phosphatase up to 3.7 times greater than in the control soil. The use of eggshell amendments may have potential as an integrated remediation strategy that enables Pb immobilization and soil biological restoration in shooting range soils.

  12. Immobilization of lead in a Korean military shooting range soil using eggshell waste: An integrated mechanistic approach

    International Nuclear Information System (INIS)

    Ahmad, Mahtab; Hashimoto, Yohey; Moon, Deok Hyun; Lee, Sang Soo; Ok, Yong Sik

    2012-01-01

    Highlights: ► Eggshell and calcined eggshell immobilized Pb in the shooting range soil. ► Calcined eggshell was more effective on Pb immobilization compared to eggshell. ► Exchangeable Pb fractions were transformed to carbonate bound fractions. ► Calcined eggshell stabilized Pb by enwrapping into calcium silicate hydrate. ► Soil Pb toxicity can be reduced by applying eggshell and calcined eggshell. - Abstract: This study evaluated the effectiveness of eggshell and calcined eggshell on lead (Pb) immobilization in a shooting range soil. Destructive and non-destructive analytical techniques were employed to determine the mechanism of Pb immobilization. The 5% additions of eggshell and calcined eggshell significantly decreased the TCLP-Pb concentration by 68.8% due mainly to increasing soil pH. Eggshell and calcined-eggshell amendments decreased the exchangeable Pb fraction to ∼1% of the total Pb in the soil, while the carbonate-associated Pb fraction was increased to 40.0–47.1% at >15% application rates. The thermodynamic modeling on Pb speciation in the soil solution predicted the precipitation of Pb-hydroxide [Pb(OH) 2 ] in soils amended with eggshell and calcined eggshell. The SEM-EDS, XAFS and elemental dot mapping revealed that Pb in soil amended with calcined eggshell was associated with Si and Ca, and may be immobilized by entrapping into calcium-silicate-hydrate. Comparatively, in the soil amended with eggshell, Pb was immobilized via formation of Pb-hydroxide or lanarkite [Pb 2 O(SO 4 )]. Applications of amendments increased activities of alkaline phosphatase up to 3.7 times greater than in the control soil. The use of eggshell amendments may have potential as an integrated remediation strategy that enables Pb immobilization and soil biological restoration in shooting range soils.

  13. The weathering and transformation process of lead in China's shooting ranges.

    Science.gov (United States)

    Li, Yeling; Zhu, Yongbing; Zhao, Sanping; Liu, Xiaodong

    2015-09-01

    Corroding steel-core bullets from three shooting ranges in different climate zones of China were collected. Multiple technical methods (EMPA, SEM, XRD, and ICP-OES) were applied to investigate the structure, morphology, and weathering product of this type of bullet in China to analyze the weathering mechanisms in different types of soils. A scanning electron microscope (SEM) was used to view the morphology and microstructure of corrosion layers. On the corroded lead layer surface, unevenness, micro cracks, and spallation were usually present. Around the micro cracks, many types of euhedral and subhedral crystals of the secondary products of lead were formed, most of which were composed of cerussite (PbCO3), while hydrocerussite (Pb3(CO3)2(OH)2) was predominant in the bullet collected from the humid environment. X-ray power diffraction (XRD) results show that the secondary weathering products in the three shooting range soils are clearly different. In the Fangyan shooting range, which has a neutral and semi-arid soil, the lead weathering product was mainly hydrocerussite (Pb3(CO3)2(OH)2), while no substantial amount of crystal phase of lead compound could be found in acidic, damp soils from the Fenghuang shooting range, possibly due to the enhanced dissolution and mobilization of lead compounds at lower pH and higher content of organic matter in the soil. In hot and arid environment of the Baicheng shooting range, cerussite might have undergone thermal decomposition, thus generating shannonite (Pb2O(CO3)). These results indicate that the formation of secondary Pb minerals is largely affected by the climatic zone or the soil properties, which may have implications for range management practices.

  14. Immobilization of lead in a Korean military shooting range soil using eggshell waste: an integrated mechanistic approach.

    Science.gov (United States)

    Ahmad, Mahtab; Hashimoto, Yohey; Moon, Deok Hyun; Lee, Sang Soo; Ok, Yong Sik

    2012-03-30

    This study evaluated the effectiveness of eggshell and calcined eggshell on lead (Pb) immobilization in a shooting range soil. Destructive and non-destructive analytical techniques were employed to determine the mechanism of Pb immobilization. The 5% additions of eggshell and calcined eggshell significantly decreased the TCLP-Pb concentration by 68.8% due mainly to increasing soil pH. Eggshell and calcined-eggshell amendments decreased the exchangeable Pb fraction to ≈ 1% of the total Pb in the soil, while the carbonate-associated Pb fraction was increased to 40.0-47.1% at >15% application rates. The thermodynamic modeling on Pb speciation in the soil solution predicted the precipitation of Pb-hydroxide [Pb(OH)(2)] in soils amended with eggshell and calcined eggshell. The SEM-EDS, XAFS and elemental dot mapping revealed that Pb in soil amended with calcined eggshell was associated with Si and Ca, and may be immobilized by entrapping into calcium-silicate-hydrate. Comparatively, in the soil amended with eggshell, Pb was immobilized via formation of Pb-hydroxide or lanarkite [Pb(2)O(SO(4))]. Applications of amendments increased activities of alkaline phosphatase up to 3.7 times greater than in the control soil. The use of eggshell amendments may have potential as an integrated remediation strategy that enables Pb immobilization and soil biological restoration in shooting range soils. Copyright © 2012 Elsevier B.V. All rights reserved.

  15. Effects of soil dilution and amendments (mussel shell, cow bone, and biochar) on Pb availability and phytotoxicity in military shooting range soil.

    Science.gov (United States)

    Ahmad, Mahtab; Soo Lee, Sang; Yang, Jae E; Ro, Hee-Myong; Han Lee, Young; Sik Ok, Yong

    2012-05-01

    Bioavailability and bioaccessibility determine the level of metal toxicity in the soils. Inorganic soil amendments may decrease metal bioavailability and enhance soil quality. This study used mussel shell, cow bone, and biochar to reduce lead (Pb) toxicity in the highly contaminated military shooting range soil in Korea. Water-soluble and 1-M ammonium nitrate extractions, and a modified physiologically based extraction test (PBET) were performed to determine Pb bioavailability and bioaccessibility in the soil, respectively. Active C in the soil was also measured to evaluate the effects of the amendments on biological soil quality. The Pb contaminated soil was diluted in serial with uncontaminated soil for the bioassays. Seed germination and root elongation tests using lettuce (Lactuca sativa) showed increases in germination percentage and root length in soil treated with the amendments. Biochar was most effective and increased seed germination by 360% and root length by 189% compared to the unamended soil. Up to 20% soil dilution resulted in more than 50% seed germination. Bioavailability and bioaccessibility of Pb in the soils were decreased by 92.5% and 48.5% with mussel shell, by 84.8% and 34.5% with cow bone, and by 75.8% and 12.5% with biochar, respectively, compared to the unamended soil. We found that the Pb availability in the military shooting range soil can be reduced effectively by the tested amendments or soil dilution alternately, thereby decreasing the risk of ecotoxicity. Furthermore, the increasing active C from the amendments revitalized the soil contaminated with Pb. Copyright © 2012 Elsevier Inc. All rights reserved.

  16. Apatite ore mine tailings as an amendment for remediation of a lead-contaminated shooting range soil.

    Science.gov (United States)

    Venäläinen, Salla H

    2011-10-01

    This study investigated the use of tailings from apatite ore beneficiation in the remediation of a heavily contaminated shooting range soil. The tailings originating in Siilinjärvi carbonatite complex, Finland, consist of apatite residues accompanied by phlogopite and calcite. In a pot experiment, organic top layer of a boreal forest soil predisposed to pellet-derived lead (Pb) was amended with tailings of various particle-sizes (Ø>0.2mm, Øremediation technique at polluted sites. Copyright © 2011 Elsevier B.V. All rights reserved.

  17. Chemical Speciation and Quantitative Evaluation of Heavy Metal Pollution Hazards in Two Army Shooting Range Backstop Soils.

    Science.gov (United States)

    Islam, Mohammad Nazrul; Nguyen, Xuan Phuc; Jung, Ho-Young; Park, Jeong-Hun

    2016-02-01

    The chemical speciation and ecological risk assessment of heavy metals in two shooting range backstop soils in Korea were studied. Both soils were highly contaminated with Cd, Cu, Pb, and Sb. The chemical speciation of heavy metals reflected the present status of contamination, which could help in promoting management practices. We-rye soil had a higher proportion of exchangeable and carbonate bound metals and water-extractable Cd and Sb than the Cho-do soil. Bioavailable Pb represented 42 % of the total Pb content in both soils. A significant amount of Sb was found in the two most bioavailable fractions, amounting to ~32 % in the soil samples, in good agreement with the batch leaching test using water. Based on the values of ecological risk indices, both soils showed extremely high potential risk and may represent serious environmental problems.

  18. Extreme soil acidity from biodegradable trap and skeet targets increases severity of pollution at shooting ranges.

    Science.gov (United States)

    McTee, Michael R; Mummey, Daniel L; Ramsey, Philip W; Hinman, Nancy W

    2016-01-01

    Lead pollution at shooting ranges overshadows the potential for contamination issues from trap and skeet targets. We studied the environmental influence of targets sold as biodegradable by determining the components of the targets and sampling soils at a former sporting clay range. Targets comprised approximately 53% CaCO3, 41% S(0), and 6% modifiers, and on a molar basis, there was 2.3 times more S(0) than CaCO3. We observed a positive correlation between target cover and SO4(2-) (ρ=0.82, Psoil pH (ρ=0.62, P=0.006). For sites that had pH values below 3, 24tons of lime per 1000tons of soil would be required to raise soil pH to 6.5. Lime-facilitated pH increases would be transitory because S(0) would continue to oxidize to H2SO4 until the S(0) is depleted. This study demonstrates that biodegradable trap and skeet targets can acidify soil, which has implications for increasing the mobility of Pb from shotgun pellets. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Lead and copper immobilization in a shooting range soil using soybean stover- and pine needle-derived biochars: Chemical, microbial and spectroscopic assessments

    International Nuclear Information System (INIS)

    Ahmad, Mahtab; Ok, Yong Sik; Rajapaksha, Anushka Upamali; Lim, Jung Eun; Kim, Byung-Yong; Ahn, Jae-Hyung; Lee, Young Han; Al-Wabel, Mohammad I; Lee, Sung-Eun; Lee, Sang Soo

    2016-01-01

    Highlights: • Biochar immobilizes Pb and Cu in a contaminated shooting range soil. • Soybean stover-biochar is an efficient metal immobilizer than pine needle-biochar. • Biochar produced at 700 °C showed significant potential of sequestering C in soil. • Biochar showed less impact on the bacterial community than feedstock biomass. - Abstract: Biochar (BC) could be a potential candidate for the remediation of metal contaminated soil. Mechanistic understandings are needed for the appropriate selection of BC and investigating molecular microbial ecological interactions. The soybean stover-derived BCs were more effective in immobilizing Pb (88%) and Cu (87%) than the pine needle-derived BCs in a contaminated shooting range soil. The sequential chemical extractions indicated that BCs stimulated the geochemical transformation of metal species. Spectroscopic investigations using scanning electron microscopic elemental dot mapping and extended X-ray absorption fine structure spectroscopic measurements showed that Pb in the BCs amended soils was immobilized by the formation of stable chloropyromorphite. Soil organic C and microbial activity were also enhanced by BC. The non-labile C fraction in the soil amended with BCs produced at 700 °C was increased. Biochars showed less impact on the bacterial community than feedstock biomass as promulgated by the pyrosequencing of 16S rRNA gene. The feedstock type (namely soybean stover and pine needles) was the main factor influencing the BCs efficacy on metals’ (im) mobilization and bacterial health in soils.

  20. Lead and copper immobilization in a shooting range soil using soybean stover- and pine needle-derived biochars: Chemical, microbial and spectroscopic assessments

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, Mahtab [Korea Biochar Research Center & Department of Biological Environment, Kangwon National University, Chuncheon 200-701 (Korea, Republic of); Soil Sciences Department, College of Food and Agricultural Sciences, King Saud University, PO Box 2460, Riyadh 11451 (Saudi Arabia); Ok, Yong Sik; Rajapaksha, Anushka Upamali; Lim, Jung Eun [Korea Biochar Research Center & Department of Biological Environment, Kangwon National University, Chuncheon 200-701 (Korea, Republic of); Kim, Byung-Yong; Ahn, Jae-Hyung [Agricultural Microbiology Division, National Academy of Agricultural Science, Rural Development Administration, Wanju 565-851 (Korea, Republic of); Lee, Young Han [Division of Plant Environment Research, Gyeongsangnam-do Agricultural Research and Extension Service, Jinju 660-360 (Korea, Republic of); Al-Wabel, Mohammad I [Soil Sciences Department, College of Food and Agricultural Sciences, King Saud University, PO Box 2460, Riyadh 11451 (Saudi Arabia); Lee, Sung-Eun, E-mail: selpest@knu.ac.kr [School of Applied Biosciences, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Lee, Sang Soo, E-mail: sslee97@kangwon.ac.kr [Korea Biochar Research Center & Department of Biological Environment, Kangwon National University, Chuncheon 200-701 (Korea, Republic of)

    2016-01-15

    Highlights: • Biochar immobilizes Pb and Cu in a contaminated shooting range soil. • Soybean stover-biochar is an efficient metal immobilizer than pine needle-biochar. • Biochar produced at 700 °C showed significant potential of sequestering C in soil. • Biochar showed less impact on the bacterial community than feedstock biomass. - Abstract: Biochar (BC) could be a potential candidate for the remediation of metal contaminated soil. Mechanistic understandings are needed for the appropriate selection of BC and investigating molecular microbial ecological interactions. The soybean stover-derived BCs were more effective in immobilizing Pb (88%) and Cu (87%) than the pine needle-derived BCs in a contaminated shooting range soil. The sequential chemical extractions indicated that BCs stimulated the geochemical transformation of metal species. Spectroscopic investigations using scanning electron microscopic elemental dot mapping and extended X-ray absorption fine structure spectroscopic measurements showed that Pb in the BCs amended soils was immobilized by the formation of stable chloropyromorphite. Soil organic C and microbial activity were also enhanced by BC. The non-labile C fraction in the soil amended with BCs produced at 700 °C was increased. Biochars showed less impact on the bacterial community than feedstock biomass as promulgated by the pyrosequencing of 16S rRNA gene. The feedstock type (namely soybean stover and pine needles) was the main factor influencing the BCs efficacy on metals’ (im) mobilization and bacterial health in soils.

  1. Sound propagation from a semi-open shooting range

    NARCIS (Netherlands)

    Eerden, F.J.M. van der; Berg, F. van den

    2011-01-01

    Semi-open shooting ranges, in contrast to a fully open shooting range, are often used in the densely populated area of the Netherlands. The Ministry of Defense operates a number of these ranges. In these shooting ranges above the line of fire a number of screens are situated for safety precautions

  2. Chemical stabilisation of lead in shooting range soils with phosphate and magnesium oxide: Synchrotron investigation

    International Nuclear Information System (INIS)

    Sanderson, Peter; Naidu, Ravi; Bolan, Nanthi; Lim, Jung Eun; Ok, Yong Sik

    2015-01-01

    Highlights: • Quantitative speciation of Pb by XAS as a result of Phosphate and MgO treatment revealed Pb converted to pyromorphite was limited. • Subsequent MgO addition increased pyromorphite formation. • Pb was precipitated on the surface of MgO as PbO. • Bioaccessibility of Pb decreased with P treatments, but not with MgO only. - Abstract: Three Australian shooting range soils were treated with phosphate and magnesium oxide, or a combination of both to chemically stabilize Pb. Lead speciation was determined after 1 month ageing by X-ray absorption spectroscopy combined with linear combination fitting in control and treated soils. The predominant Pb species in untreated soils were iron oxide bound Pb, humic acid bound Pb and the mineral litharge. Treatment with phosphate resulted in substantial pyromorphite formation in two of the soils (TV and PE), accounting for up to 38% of Pb species present, despite the addition of excess phosphate. In MgO treated soils only, up to 43% of Pb was associated with MgO. Litharge and Pb hydroxide also formed as a result of MgO addition in the soils. Application of MgO after P treatment increased hydroxypyromorphite/pyromorphite formation relative to soils teated with phosphate only. X-ray diffraction and Scanning electron microscopy revealed PbO precipitate on the surface of MgO. Soil pH, (5.3–9.3) was an important parameter, as was the solubility of existing Pb species. The use of direct means of determination of the stabilisation of metals such as by X-ray absorption spectroscopy is desirable, particularly in relation to understanding long term stability of the immobilised contaminants.

  3. Chemical stabilisation of lead in shooting range soils with phosphate and magnesium oxide: Synchrotron investigation

    Energy Technology Data Exchange (ETDEWEB)

    Sanderson, Peter [Centre for Environmental Risk Assessment and Remediation and CRC for Contamination Assessment and Remediation of the Environment (CRC CARE), University of South Australia, University Parade, 5095 Mawson Lakes (Australia); Naidu, Ravi, E-mail: ravi.naidu@crccare.com [Centre for Environmental Risk Assessment and Remediation and CRC for Contamination Assessment and Remediation of the Environment (CRC CARE), University of South Australia, University Parade, 5095 Mawson Lakes (Australia); Bolan, Nanthi [Centre for Environmental Risk Assessment and Remediation and CRC for Contamination Assessment and Remediation of the Environment (CRC CARE), University of South Australia, University Parade, 5095 Mawson Lakes (Australia); Lim, Jung Eun; Ok, Yong Sik [Korea Biochar Research Center & Department of Biological Environment, Kangwon National University, Chuncheon 200-701 (Korea, Republic of)

    2015-12-15

    Highlights: • Quantitative speciation of Pb by XAS as a result of Phosphate and MgO treatment revealed Pb converted to pyromorphite was limited. • Subsequent MgO addition increased pyromorphite formation. • Pb was precipitated on the surface of MgO as PbO. • Bioaccessibility of Pb decreased with P treatments, but not with MgO only. - Abstract: Three Australian shooting range soils were treated with phosphate and magnesium oxide, or a combination of both to chemically stabilize Pb. Lead speciation was determined after 1 month ageing by X-ray absorption spectroscopy combined with linear combination fitting in control and treated soils. The predominant Pb species in untreated soils were iron oxide bound Pb, humic acid bound Pb and the mineral litharge. Treatment with phosphate resulted in substantial pyromorphite formation in two of the soils (TV and PE), accounting for up to 38% of Pb species present, despite the addition of excess phosphate. In MgO treated soils only, up to 43% of Pb was associated with MgO. Litharge and Pb hydroxide also formed as a result of MgO addition in the soils. Application of MgO after P treatment increased hydroxypyromorphite/pyromorphite formation relative to soils teated with phosphate only. X-ray diffraction and Scanning electron microscopy revealed PbO precipitate on the surface of MgO. Soil pH, (5.3–9.3) was an important parameter, as was the solubility of existing Pb species. The use of direct means of determination of the stabilisation of metals such as by X-ray absorption spectroscopy is desirable, particularly in relation to understanding long term stability of the immobilised contaminants.

  4. Exposure to lead in South African shooting ranges

    International Nuclear Information System (INIS)

    Mathee, Angela; Jager, Pieter de; Naidoo, Shan; Naicker, Nisha

    2017-01-01

    Introduction: Lead exposure in shooting ranges has been under scrutiny for decades, but no information in this regard is available in respect of African settings, and in South Africa specifically. The aim of this study was to determine the blood lead levels in the users of randomly selected private shooting ranges in South Africa's Gauteng province. Methods: An analytical cross sectional study was conducted, with participants recruited from four randomly selected shooting ranges and three archery ranges as a comparator group. Results: A total of 118 (87 shooters and 31 archers) were included in the analysis. Shooters had significantly higher blood lead levels (BLL) compared to archers with 36/85 (42.4%) of shooters versus 2/34 (5.9%) of archers found to have a BLL ≥10 μg/dl (p<0.001). Conclusion: Shooting ranges may constitute an import site of elevated exposure to lead. Improved ventilation, low levels of awareness of lead hazards, poor housekeeping, and inadequate personal hygiene facilities and practices at South African shooting ranges need urgent attention. - Highlights: • This is the first study, to our knowledge, of lead exposure in shooting ranges in an African setting. • This study indicates highly elevated lead exposure amongst the users of certain private shooting ranges in South Africa. • Lead exposure may be a serious, yet under-studied, source of adult lead exposure in South Africa, and possibly elsewhere on the African continent.

  5. Exposure to lead in South African shooting ranges

    Energy Technology Data Exchange (ETDEWEB)

    Mathee, Angela [South African Medical Research Council, Environment & Health Research Unit, PO Box 87373, Houghton 2041 (South Africa); University of the Witwatersrand (School of Public Health), PO Box Wits, Johannesburg 2050 (South Africa); University of Johannesburg (Environmental Health Department, Faculty of Health Sciences), PO Box 524, Auckland Park, Johannesburg 2006 (South Africa); Jager, Pieter de [University of the Witwatersrand (School of Public Health), PO Box Wits, Johannesburg 2050 (South Africa); National Health Laboratory Service (Epidemiology and Surveillance Unit, National Institute for Occupational Health), PO Box 4788, Johannesburg 2000 (South Africa); Naidoo, Shan [University of the Witwatersrand (School of Public Health), PO Box Wits, Johannesburg 2050 (South Africa); Naicker, Nisha [South African Medical Research Council, Environment & Health Research Unit, PO Box 87373, Houghton 2041 (South Africa); University of the Witwatersrand, School of Public Health, PO Box Wits, Johannesburg 2050 (South Africa); University of Johannesburg, Environmental Health Department, Faculty of Health Sciences, PO Box 524, Auckland Park, Johannesburg 2006 (South Africa)

    2017-02-15

    Introduction: Lead exposure in shooting ranges has been under scrutiny for decades, but no information in this regard is available in respect of African settings, and in South Africa specifically. The aim of this study was to determine the blood lead levels in the users of randomly selected private shooting ranges in South Africa's Gauteng province. Methods: An analytical cross sectional study was conducted, with participants recruited from four randomly selected shooting ranges and three archery ranges as a comparator group. Results: A total of 118 (87 shooters and 31 archers) were included in the analysis. Shooters had significantly higher blood lead levels (BLL) compared to archers with 36/85 (42.4%) of shooters versus 2/34 (5.9%) of archers found to have a BLL ≥10 μg/dl (p<0.001). Conclusion: Shooting ranges may constitute an import site of elevated exposure to lead. Improved ventilation, low levels of awareness of lead hazards, poor housekeeping, and inadequate personal hygiene facilities and practices at South African shooting ranges need urgent attention. - Highlights: • This is the first study, to our knowledge, of lead exposure in shooting ranges in an African setting. • This study indicates highly elevated lead exposure amongst the users of certain private shooting ranges in South Africa. • Lead exposure may be a serious, yet under-studied, source of adult lead exposure in South Africa, and possibly elsewhere on the African continent.

  6. Potential value of phosphate compounds in enhancing immobilization and reducing bioavailability of mixed heavy metal contaminants in shooting range soil.

    Science.gov (United States)

    Seshadri, B; Bolan, N S; Choppala, G; Kunhikrishnan, A; Sanderson, P; Wang, H; Currie, L D; Tsang, Daniel C W; Ok, Y S; Kim, G

    2017-10-01

    Shooting range soils contain mixed heavy metal contaminants including lead (Pb), cadmium (Cd), and zinc (Zn). Phosphate (P) compounds have been used to immobilize these metals, particularly Pb, thereby reducing their bioavailability. However, research on immobilization of Pb's co-contaminants showed the relative importance of soluble and insoluble P compounds, which is critical in evaluating the overall success of in situ stabilization practice in the sustainable remediation of mixed heavy metal contaminated soils. Soluble synthetic P fertilizer (diammonium phosphate; DAP) and reactive (Sechura; SPR) and unreactive (Christmas Island; CPR) natural phosphate rocks (PR) were tested for Cd, Pb and Zn immobilization and later their mobility and bioavailability in a shooting range soil. The addition of P compounds resulted in the immobilization of Cd, Pb and Zn by 1.56-76.2%, 3.21-83.56%, and 2.31-74.6%, respectively. The reactive SPR significantly reduced Cd, Pb and Zn leaching while soluble DAP increased their leachate concentrations. The SPR reduced the bioaccumulation of Cd, Pb and Zn in earthworms by 7.13-23.4% and 14.3-54.6% in comparison with earthworms in the DAP and control treatment, respectively. Bioaccessible Cd, Pb and Zn concentrations as determined using a simplified bioaccessibility extraction test showed higher long-term stability of P-immobilized Pb and Zn than Cd. The differential effect of P-induced immobilization between P compounds and metals is due to the variation in the solubility characteristics of P compounds and nature of metal phosphate compounds formed. Therefore, Pb and Zn immobilization by P compounds is an effective long-term remediation strategy for mixed heavy metal contaminated soils. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Effects of Microbial and Phosphate Amendments on the Bioavailability of Lead (Pb) in Shooting Range Soil

    Energy Technology Data Exchange (ETDEWEB)

    Brigmon, Robin; Wilson, Christina; Knox, Anna; Seaman, John; Smith, Garriet

    2005-06-16

    , or U and contains about 27% total phosphate, most of which is available. FA and NCA are two types of rock phosphates that release small amounts of phosphate over time. Total phosphate is around 30% with only 1-2% phosphate available (Knox et al. 2005). In this study, we describe the influence of combining the two microbial and three phosphate amendments on reducing lead bioavailability in shooting range soil.

  8. Counter-current acid leaching process for the removal of Cu, Pb, Sb and Zn from shooting range soil.

    Science.gov (United States)

    Lafond, Stéphanie; Blais, Jean-François; Mercier, Guy; Martel, Richard

    2013-01-01

    This research explores the performance of a counter-current leaching process (CCLP) for Cu, Pb, Sb and Zn extraction in a polluted shooting range soil. The initial metal concentrations in the soil were 1790 mg Cu/kg, 48,300 mg Pb/kg, 840 mg Sb/kg and 368 mg Zn/kg. The leaching process consisted of five one-hour acid leaching steps, which used 1 M H2SO4 + 4 M NaCl (20 degrees C, soil suspension = 100 g/L) followed by two water rinsing steps. Ten counter-current remediation cycles were completed and the average metal removal yields were 98.3 +/- 0.3% of Cu, 99.5 +/- 0.1% of Pb, 75.5 +/- 5.1% of Sb and 29.1 +/- 27.2% of Zn. The quality of metal leaching did not deteriorate throughout the 10 remediation cycles completed for this study. The CCLP reduced acid and salt use by approximately 68% and reduced water consumption by approximately 60%, exceeding reductions achieved by a standard acid leaching process.

  9. Plant uptake of trace elements on a Swiss military shooting range: Uptake pathways and land management implications

    Energy Technology Data Exchange (ETDEWEB)

    Robinson, Brett H. [Swiss Federal Institute of Technology (ETH), Universitaetstrasse 16, CH-8092 Zuerich (Switzerland)], E-mail: brett.robinson@env.ethz.ch; Bischofberger, Simone; Stoll, Andreas; Schroer, Dirk; Furrer, Gerhard; Roulier, Stephanie; Gruenwald, Anna; Attinger, Werner; Schulin, Rainer [Swiss Federal Institute of Technology (ETH), Universitaetstrasse 16, CH-8092 Zuerich (Switzerland)

    2008-06-15

    Over 400 tons of Pb enters Swiss soils annually at some 2000 military shooting ranges (MSRs). We measured elements in the leaves of 10 plant species and associated rhizospheric soil on the stop butt of a disused MSR. The geometric mean concentrations of Pb, Sb, Cu, Ni in rhizospheric soils were 10,171 mg/kg, 5067 mg/kg, 4125 mg/kg and 917 mg/kg. Some species contained Pb, Cu and Ni, above concentrations (30 mg/kg, 25 mg/kg and 50 mg/kg) shown to be toxic to livestock. Most contaminants in leaves resulted from surface deposition. However, at soil Pb concentrations >60,000 mg/kg, Equisetum arvense and Tussilago farfara took up >1000 mg/kg Pb into the leaves. These plants are not hyperaccumulators, having <100 mg/kg Pb in leaves at lower soil concentrations. Removal of soil with more than 30,000 Pb, from which one could smelt this metal to offset remediation costs, followed by revegetation, would minimise dust and hence leaf-borne contaminants. - Establishment of a complete vegetation cover on shooting ranges would reduce the contamination of plant leaves by toxic trace elements.

  10. Capability of selected crop plants for shoot mercury accumulation from polluted soils: phytoremediation perspectives.

    Science.gov (United States)

    Rodriguez, Luis; Rincón, Jesusa; Asencio, Isaac; Rodríguez-Castellanos, Laura

    2007-01-01

    High-biomass crops can be considered as an alternative to hyperaccumulator plants to phytoremediate soils contaminated by heavy metals. In order to assess their practical capability for the absorption and accumulation of Hg in shoots, barley, white lupine, lentil, and chickpea were tested in pot experiments using several growth substrates. In the first experimental series, plants were grown in a mixture of vermiculite and perlite spiked with 8.35 microg g(-1) d.w. of soluble Hg. The mercury concentration of the plants' aerial tissues ranged from 1.51 to 5.13 microg g(-1) d.w. with lentil and lupine showing the highest values. In a second experiment carried out using a Hg-polluted soil (32.16 microg g(-1) d.w.) collected from a historical mining area (Almadén, Spain), the crop plants tested only reached shoot Hg concentration up to 1.13 microg g(-1) d.w. In the third experimental series, the Almadén soil was spiked with 1 microg g(-1) d.w. of soluble Hg; as a result, mercury concentrations in the plant shoots increased approximately 6 times for lupine, 5 times for chickpea, and 3.5 times for barley and lentil, with respect to those obtained with the original soil without Hg added. This marked difference was attributed to the low availability of Hg in the original Almadin soil and its subsequent increase in the Hg-spiked soil. The low mercury accumulation yields obtained for all plants do not make a successful decontamination of the Almadén soils possible byphytoremediation using crop plants. However, since the crops tested can effectively decrease the plant-available Hg level in this soil, their use could, to some extent, reduce the environmental risk of Hg pollution in the area.

  11. THE PRELIMINARY STUDIES ON THE INFLUENCE OF SHOOTING RANGES ON ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    Karolina Wodnik

    2017-08-01

    Full Text Available The aim of the study was to assess the impact of the shooting activity on the environment. The studies were conducted in the area of the sports shooting range. The invertebrates assemblages were identified to the family level as well as morphospecies. The second method do not require the proficiency in identification. The following indices of the biodiversity were used for the assessment of the impact of sports shooting ranges: Simpson, Shannon-Wiener, Margalef, Berger-Parker and Menhinick. A decreased biodiversity was observed at two studied sites comparing to the reference site what proves the influence of shooting activity on the biodiversity and suggest disturbance of the ecosystem integrity because of shooting activity.

  12. The effect of tillage intensity on soil structure and winter wheat root/shoot growth

    DEFF Research Database (Denmark)

    Munkholm, Lars Juhl; Hansen, Elly Møller; Olesen, Jørgen E

    2008-01-01

    was followed during the growing seasons using spectral reflectance and mini-rhizotron measurements, respectively. A range of soil physical properties were measured. We found decreased early season shoot and root growth with decreasing tillage intensity. Differences diminished later in the growing season...... of this study was to investigate the effect of tillage intensity on crop growth dynamics and soil structure. A tillage experiment was established in autumn 2002 on two Danish sandy loams (Foulum and Flakkebjerg) in a cereal-based crop rotation. The tillage systems included in this study were direct drilling (D...... with decreasing tillage intensity for the first year winter wheat at Foulum. In general ploughing resulted in the highest grain yields. This study highlights the important interaction between soil structure and crop growth dynamics....

  13. A Hybrid Finite Element/Helmholtz-Kirchhoff-Integral Model for Shooting Range Sound Prediction

    NARCIS (Netherlands)

    Nijhof, M.J.J.; Eerden, F.J.M. van der

    2013-01-01

    National legislation enforces a limit on the Sound Levels of outdoor military shooting ranges observed in nearby residential areas. These restrictions directly influence the number of shots that may be fired at a specific shooting range, which may conflict with the required/ scheduled training

  14. The dependence of water potential in shoots of Picea abies on air and soil water status

    Directory of Open Access Journals (Sweden)

    A. Sellin

    Full Text Available Where there is sufficient water storage in the soil the water potential (Ψx in shoots of Norway spruce [Picea abies (L. Karst.] is strongly governed by the vapour pressure deficit of the atmosphere, while the mean minimum values of Ψx usually do not drop below –1.5 MPa under meteorological conditions in Estonia. If the base water potential (Ψb is above –0.62 MPa, the principal factor causing water deficiency in shoots of P. abies may be either limited soil water reserves or atmospheric evaporative demand depending on the current level of the vapour pressure deficit. As the soil dries the stomatal control becomes more efficient in preventing water losses from the foliage, and the leaf water status, in turn, less sensitive to atmospheric demand. Under drought conditions, if Ψb falls below –0.62 MPa, the trees' water stress is mainly caused by low soil water availability. Further declines in the shoot water potential (below –1.5 MPa can be attributed primarily to further decreases in the soil water, i.e. to the static water stress.Key words. Hydrology (evapotranspiration · plant ecology · soil moisture.

  15. An investigation of inorganic antimony species and antimony associated with soil humic acid molar mass fractions in contaminated soils

    International Nuclear Information System (INIS)

    Steely, Sarah; Amarasiriwardena, Dulasiri; Xing Baoshan

    2007-01-01

    The presence of antimony compounds is often suspected in the soil of apple orchards contaminated with lead arsenate pesticide and in the soil of shooting ranges. Nitric acid (1 M) extractable Sb from the shooting range (8300 μg kg -1 ) and the apple orchard (69 μg kg -1 ) had considerably higher surface Sb levels than the control site ( -1 ), and Sb was confined to the top ∼30 cm soil layer. Sb(V) was the principal species in the shooting range and the apple orchard surface soils. Size exclusion chromatography-inductively coupled plasma-mass spectrometry (SEC-ICP-MS) analysis of humic acids isolated from the two contaminated soils demonstrated that Sb has complexed to humic acid molar mass fractions. The results also indicate that humic acids have the ability to arrest the mobility of Sb through soils and would be beneficial in converting Sb(III) to a less toxic species, Sb(V), in contaminated areas. - The soil surface and depth distribution Sb(V) and Sb(III) species in a contaminated apple orchard and a shooting range, and the effect soil humic acids on inorganic antimony species is reported

  16. Shoot organogenesis in oleaster (Elaeagnus angustifolia L.)

    African Journals Online (AJOL)

    STORAGESEVER

    2009-02-04

    Feb 4, 2009 ... Regenerated plantlets were acclimatized and successfully transplanted to soil. Key words: shoot organogenesis, callus, ... saline and alkaline soils (Economou and Maloupa, 1995). Its fruits have been used as a .... cally inert compounds as reported by Kaminek (1992). Direct shoot organogenesis without ...

  17. Cover crop root, shoot, and rhizodeposit contributions to soil carbon in a no- till corn bioenergy cropping system

    Science.gov (United States)

    Austin, E.; Grandy, S.; Wickings, K.; McDaniel, M. D.; Robertson, P.

    2016-12-01

    Crop residues are potential biofuel feedstocks, but residue removal may result in reduced soil carbon (C). The inclusion of a cover crop in a corn bioenergy system could provide additional biomass and as well as help to mitigate the negative effects of residue removal by adding belowground C to stable soil C pools. In a no-till continuous corn bioenergy system in the northern portion of the US corn belt, we used 13CO2 pulse labeling to trace C in a winter rye (secale cereale) cover crop into different soil C pools for two years following rye termination. Corn stover contributed 66 (another 163 was in harvested corn stover), corn roots 57, rye shoot 61, rye roots 59, and rye rhizodeposits 27 g C m-2 to soil C. Five months following cover crop termination, belowground cover crop inputs were three times more likely to remain in soil C pools and much of the root-derived C was in mineral- associated soil fractions. Our results underscore the importance of cover crop roots vs. shoots as a source of soil C. Belowground C inputs from winter cover crops could substantially offset short term stover removal in this system.

  18. Plant-induced changes in soil chemistry do not explain differences in uranium transfer

    International Nuclear Information System (INIS)

    Duquene, L.; Vandenhove, H.; Tack, F.; Avoort, E. van der; Hees, M. van; Wannijn, J.

    2006-01-01

    A greenhouse experiment was set up with maize, ryegrass, Indian mustard, wheat and pea to evaluate to what extent differences in uranium (U) transfer factors can be explained by root-mediated changes in selected soil properties. The experiment involved an acid and an alkaline soil contaminated with 238 U. U soil-to-shoot transfer factors (TFs) ranged between 0.0005 and 0.021 on the acid soil and between 0.007 and 0.179 on the alkaline soil. Indian mustard showed the highest U uptake in shoots and maize the lowest. The root TFs, only available for the acid soil, ranged from 0.58 for maize and Indian mustard to 1.38 for ryegrass. The difference in U uptake between the two soils and the five plants was only partially explained by the different initial U concentrations in soil solution or differences in soil properties in the two soils. However, we obtained a significant relation for differences in shoot TFs observed between the two soils when relating shoot TFs with concentration of UO 2 2+ and uranyl carbonate complexes in soil solution (R 2 = 0.88). The physiological mechanisms by which root-to-shoot U transfer is inhibited or promoted seemed at least as important as the plant-induced changes in soil characteristics in determining soil-to-shoot TFs

  19. The effect of environmental conditions and soil physicochemistry on phosphate stabilisation of Pb in shooting range soils.

    Science.gov (United States)

    Sanderson, Peter; Naidu, Ravi; Bolan, Nanthi

    2016-04-01

    The stabilisation of Pb in the soil by phosphate is influenced by environmental conditions and physicochemical properties of the soils to which it is applied. Stabilisation of Pb by phosphate was examined in four soils under different environmental conditions. The effect of soil moisture and temperature on stabilisation of Pb by phosphate was examined by measurement of water extractable and bioaccessible Pb, sequential fractionation and X-ray absorption spectroscopy. The addition of humic acid, ammonium nitrate and chloride was also examined for inhibition or improvement of Pb stability with phosphate treatment. The effect of moisture level varied between soils. In soil MB and DA a soil moisture level of 50% water holding capacity was sufficient to maximise stabilisation of Pb, but in soil TV and PE reduction in bioaccessible Pb was inhibited at this moisture level. Providing moisture at twice the soil water holding capacity did not enhance the effect of phosphate on Pb stabilisation. The difference of Pb stability as a result of incubating phosphate treated soils at 18 °C and 37 °C was relatively small. However wet-dry cycles decreased the effectiveness of phosphate treatment. The reduction in bioaccessible Pb obtained was between 20 and 40% with the most optimal treatment conditions. The reduction in water extractable Pb by phosphate was substantial regardless of incubation conditions and the effect of different temperature and soil moisture regimes was not significant. Selective sequential extraction showed phosphate treatment converted Pb in fraction 1 (exchangeable, acid and water soluble) to fraction 2 (reducible). There were small difference in fraction 4 (residual) Pb and fraction 1 as a result of treatment conditions. X-ray absorption spectroscopy of stabilised PE soil revealed small differences in Pb speciation under varying soil moisture and temperature treatments. The addition of humic acid and chloride produced the greatest effect on Pb speciation in

  20. Evaluation of soil metal bioavailability estimates using two plant species (L. perenne and T. aestivum) grown in a range of agricultural soils treated with biosolids and metal salts

    International Nuclear Information System (INIS)

    Black, Amanda; McLaren, Ronald G.; Reichman, Suzanne M.; Speir, Thomas W.; Condron, Leo M.

    2011-01-01

    Few studies have quantified the accuracy of soil metal bioavailability assays using large datasets. A meta-analysis from experiments spanning 6 months to 13 years on 12 soil types, compared bioavailability estimate efficiencies for wheat and ryegrass. Treatments included biosolids ± metals, comparing total metal, Ca(NO 3 ) 2 , EDTA, soil solution, DGT and free ion activity. The best correlations between soil metal bioavailability and shoot concentrations were for Ni using Ca(NO 3 ) 2 (r 2 = 0.72) which also provided the best estimate of Zn bioavailability (r 2 = 0.64). DGT provided the best estimate of Cd bioavailability, accounting for 49% of shoot Cd concentrations. There was no reliable descriptor of Cu bioavailability, with less than 35% of shoot Cu concentrations defined. Thus interpretation of data obtained from many soil metal bioavailability assays is unreliable and probably flawed, and there is little justification to look beyond Ca(NO 3 ) 2 for Ni and Zn, and DGT for Cd. - Highlights: → A meta-analysis evaluated the efficacy of soil metal bioavailability assays. → DGT could explain 49% of shoot Cd concentration. → There is little justification to look beyond Ca(NO 3 ) 2 for Ni and Zn. - A meta-analysis of soil metal bioavailability estimates for 12 soil types concluded that there is little justification to look beyond Ca(NO 3 ) 2 for Ni and Zn, and DGT for Cd.

  1. Influence of fertilizer placements on the root and shoot growth of soybean

    International Nuclear Information System (INIS)

    Sisworo, E.L.

    1983-01-01

    Two experiments have been carried out to obtain data of soybean growth in relation to fertilizer placements in the soil. Treatments in these two experiments were: fertilizer (N, P, and K) placements at the soil surface, 5, 10, and 15 cm beneath the soil surface and the plants were harvested at the age of 51, 58, and 65 days after seed planting, in the first experiment, and in the second experiment plants were harvested at the age of 37, 44, and 51 days after seed planting. The parameter for root growth was the percentage of roots in soil depths at: 0-5, 5-10, 10-15, and 15-20 cm, respectively, while for shoot growth the parameters were the dry weight of the shoot, plant height, and number of flowers and pods. Data obtained from these two experiments showed that fertilizer placements at several soil depths have no influence on the growth of root and shoot. The highest shoot growth was at 0-5 cm soil depth, but this does not cause highest shoot growth. Different harvest time do not effect root growth, but it has a highly siginificant on shoot growth. The soybean plants were planted in PVC pots with a 6 kg soil capacity, and the pots were placed outside the green house. (author)

  2. Arsenic speciation in moso bamboo shoot - A terrestrial plant that contains organoarsenic species

    Energy Technology Data Exchange (ETDEWEB)

    Zhao Rui [Department of Chemistry, Key laboratory for Atomic and Molecular Nanosciences of Education Ministry, Tsinghua University, Beijing 100084, P.R. China (China); Zhao Mengxia [Department of Chemistry, Key laboratory for Atomic and Molecular Nanosciences of Education Ministry, Tsinghua University, Beijing 100084 (China); Wang Hui [Department of Chemistry, Key laboratory for Atomic and Molecular Nanosciences of Education Ministry, Tsinghua University, Beijing 100084 (China); Taneike, Yasuhito [Shimadzu Co Ltd, Spectroscopy Business Unit Analytical Instruments Div, Nakagyo Ku, Kyoto, 6048511 (Japan); Zhang Xinrong [Department of Chemistry, Key laboratory for Atomic and Molecular Nanosciences of Education Ministry, Tsinghua University, Beijing 100084 (China)]. E-mail: xrzhang@chem.tsinghua.edu.cn

    2006-12-01

    Arsenic is predominantly found as an inorganic species in most terrestrial plants. However, we found that a significant proportion of organic arsenic was present in moso bamboo (Phyllostachys pubescens Mazel) shoot in a market survey of arsenic species in edible terrestrial plants. Moso bamboo shoots from different producing areas in China were collected for analysis to confirm the ubiquity of methylated arsenic species. The total arsenic concentrations of bamboo shoots were determined by hydride generation coupled atomic fluorescence spectrometry (HG-AFS), ranging from 27.7 to 94.0 {mu}g/kg. Information about arsenic species was acquired from cold trap-hydride generation-atomic absorption spectrometry (CT-HG-AAS). Dimethylarsinic acid (DMA) was present in the amount of 13.9% to 44.9% of sum of the arsenic species in all these samples. Monomethylarsonic acid (MMA) and trimethylarsine oxide (TMAO) were also detected in certain samples in the range of 4.2-16.5% and 11.8-18.4%, respectively. In addition, bamboo shoots collected in winter were found to have more total arsenic and organic arsenic than those collected in spring. To investigate the source of the organic arsenic in moso bamboo shoots, arsenic species in the rhizosphere soils of the plants were examined. The absence of organic arsenic in soils would suggest the possibility of formation of methylated arsenic in the plants. In addition, studies of arsenic speciation in the peel and core of winter bamboo shoots showed that all the cores contained organic arsenic while no organic arsenic was detected in the peels. The study provides useful information for better understanding of the distribution of arsenic species in terrestrial plants.

  3. Evaluation of soil metal bioavailability estimates using two plant species (L. perenne and T. aestivum) grown in a range of agricultural soils treated with biosolids and metal salts

    Energy Technology Data Exchange (ETDEWEB)

    Black, Amanda, E-mail: amanda.black@lincoln.ac.nz [Department of Soil and Physical Sciences, Faculty of Agriculture and Life Sciences, Lincoln University, PO Box 84, Lincoln 7647, Christchurch (New Zealand); McLaren, Ronald G. [Department of Soil and Physical Sciences, Faculty of Agriculture and Life Sciences, Lincoln University, PO Box 84, Lincoln 7647, Christchurch (New Zealand); Reichman, Suzanne M. [School of Civil, Environmental and Chemical Engineering, RMIT University, GPO Box 2476, Melbourne 3001 (Australia); Speir, Thomas W. [Institute of Environmental Science and Research Ltd (ESR), PO Box 50348, Porirua 5240 (New Zealand); Condron, Leo M. [Department of Soil and Physical Sciences, Faculty of Agriculture and Life Sciences, Lincoln University, PO Box 84, Lincoln 7647, Christchurch (New Zealand)

    2011-06-15

    Few studies have quantified the accuracy of soil metal bioavailability assays using large datasets. A meta-analysis from experiments spanning 6 months to 13 years on 12 soil types, compared bioavailability estimate efficiencies for wheat and ryegrass. Treatments included biosolids {+-} metals, comparing total metal, Ca(NO{sub 3}){sub 2}, EDTA, soil solution, DGT and free ion activity. The best correlations between soil metal bioavailability and shoot concentrations were for Ni using Ca(NO{sub 3}){sub 2} (r{sup 2} = 0.72) which also provided the best estimate of Zn bioavailability (r{sup 2} = 0.64). DGT provided the best estimate of Cd bioavailability, accounting for 49% of shoot Cd concentrations. There was no reliable descriptor of Cu bioavailability, with less than 35% of shoot Cu concentrations defined. Thus interpretation of data obtained from many soil metal bioavailability assays is unreliable and probably flawed, and there is little justification to look beyond Ca(NO{sub 3}){sub 2} for Ni and Zn, and DGT for Cd. - Highlights: > A meta-analysis evaluated the efficacy of soil metal bioavailability assays. > DGT could explain 49% of shoot Cd concentration. > There is little justification to look beyond Ca(NO{sub 3}){sub 2} for Ni and Zn. - A meta-analysis of soil metal bioavailability estimates for 12 soil types concluded that there is little justification to look beyond Ca(NO{sub 3}){sub 2} for Ni and Zn, and DGT for Cd.

  4. Release of carbon and nitrogen from fodder radish (Raphanus sativus) shoots and roots incubated in soils with different management history

    DEFF Research Database (Denmark)

    Hu, Teng; Olesen, Jørgen Eivind; Christensen, Bent Tolstrup

    2018-01-01

    and roots from fodder radish (Raphanus sativus oleiformis L.), a widely used cover crop, on the release of their C and N after addition to soil. Shoots and roots were incubated for 180 d at 20°C using four soils with different management histories (organic versus mineral fertiliser, with and without use...

  5. Mass propagation of shoots of Stevia rebaudiana using a large scale bioreactor.

    Science.gov (United States)

    Akita, M; Shigeoka, T; Koizumi, Y; Kawamura, M

    1994-01-01

    A procedure for the mass propagation of multiple shoots of Stevia rebaudiana is described. Isolated shoot primordia were used as the inoculum to obtain clusters of shoot primordia. Such clusters were grown in a 500 liter bioreactor to obtain shoots. A total of 64.6 Kg of shoots were propagated from 460 g of the inoculated shoot primordia. These shoots were easily acclimatized in soil.

  6. Water deficit stress effects on corn (Zea mays, L.) root: shoot ratio

    Science.gov (United States)

    A study was conducted at Akron, CO, USA, on a Weld silt loam in 2004 to quantify the effects of water deficit stress on corn (Zea mays, L.) root and shoot biomass. Corn plants were grown under a range of soil bulk density and water conditions caused by previous tillage, crop rotation, and irrigation...

  7. Characterizing the Suitability of Selected Indigenous Soil Improving Legumes in a Humid Tropical Environment Using Shoot and Root Attributes

    Directory of Open Access Journals (Sweden)

    Anikwe, MAN.

    2003-01-01

    Full Text Available We studied the biomass accumulation, root length, nodulation, and chemical composition of roots and shoot of ten indigenous soil improving legumes in a humid tropical ecosystem with the view to selecting species for soil improvement programmes. Two cultivars of Vigna unguiculata, and one each of Glycine max, Arachis hypogaea, Crotararia ochroleuca, Cajanus cajan, Pueraria phaseoloides, Lablab purpureus, Mucuna pruriens and Vigna subterranea as treatments were planted in 20 kg pots containing soil from an Oxic paleustalf in Nigeria. The pots were arranged in randomized complete block layout with three replications in a greenhouse at IITA Ibadan, Nigeria. Results from the work show that M. pruriens and C. cajan produced the highest quantity of biomass. Root elongation was highest in M. pruriens whereas A. hypogaea produced the most root nodules with native rhizobia. The highest quantity of nodule dry weight was produced by A. hypogaea and P. phaseoloides whereas most of the legumes except G. max and P. phaseoloides had high and statistically comparable N content of between 2.36 and 3.34 mg.kg-1 N. The results show that the legumes have different root and shoot characteristics, which should be taken into consideration when selecting species for soil improvement programmes.

  8. In vitro regeneration of Salix nigra from adventitious shoots.

    Science.gov (United States)

    Lyyra, Satu; Lima, Amparo; Merkle, Scott A

    2006-07-01

    Black willow (Salix nigra Marsh.) is the largest and only commercially important willow species in North America. It is a candidate for phytoremediation of polluted soils because it is fast-growing and thrives on floodplains throughout eastern USA. Our objective was to develop a protocol for the in vitro regeneration of black willow plants that could serve as target material for gene transformation. Unexpanded inflorescence explants were excised from dormant buds collected from three source trees and cultured on woody plant medium (WPM) supplemented with one of: (1) 0.1 mg l(-1) thidiazuron (TDZ); (2) 0.5 mg l(-1) 6-benzoaminopurine (BAP); or (3) 1 mg l(-1) BAP. All plant growth regulator (PGR) treatments induced direct adventitious bud formation from the genotypes. The percentage of explants producing buds ranged from 20 to 92%, depending on genotype and treatment. Although most of the TDZ-treated inflorescences produced buds, these buds failed to elongate into shoots. Buds on explants treated with BAP elongated into shoots that were easily rooted in vitro and further established in potting mix in high humidity. The PGR treatments significantly affected shoot regeneration frequency (P < 0.01). The highest shoot regeneration frequency (36%) was achieved with Genotype 3 cultured on 0.5 mg l(-1) BAP. Mean number of shoots per explant varied from one to five. The ability of black willow inflorescences to produce adventitious shoots makes them potential targets for Agrobacterium-mediated transformation with heavy-metal-resistant genes for phytoremediation.

  9. Fractionation and distribution of risk elements in soil profiles at a Czech shooting range

    Czech Academy of Sciences Publication Activity Database

    Ash, C.; Tejnecký, V.; Šebek, O.; Němeček, K.; Žahourová-Dubová, L.; Bakardjieva, Snejana; Drahota, P.; Drábek, O.

    2013-01-01

    Roč. 59, č. 3 (2013), s. 121-129 ISSN 1214-1178 Institutional support: RVO:61388980 Keywords : lead * inorganic contaminants * BCR sequential extraction * soil probe * alkaline soil Subject RIV: CA - Inorganic Chemistry Impact factor: 1.113, year: 2013

  10. Soil nutrient patchiness and genotypes interact on the quantity, quality and decomposition of roots versus shoots of Triticum aestivum.

    NARCIS (Netherlands)

    He, W.M.; Shen, Y.; Cornelissen, J.H.C.

    2012-01-01

    Aims: The purpose of this study was to test the hypotheses that soil nutrient patchiness can differentially benefit the decomposition of root and shoot litters and that this facilitation depends on plant genotypes. Methods: We grew 15 cultivars (i. e. genotypes) of winter wheat (Triticum aestivum

  11. Transcriptomic Analysis of Soil-Grown Arabidopsis thaliana Roots and Shoots in Response to a Drought Stress

    Directory of Open Access Journals (Sweden)

    Sultana eRasheed

    2016-02-01

    Full Text Available Drought stress has a negative impact on crop yield. Thus, understanding the molecular mechanisms responsible for plant drought stress tolerance is essential for improving this beneficial trait in crops. In the current study, a transcriptional analysis was conducted of gene regulatory networks in roots of soil-grown Arabidopsis plants in response to a drought stress treatment. A microarray analysis of drought-stressed roots and shoots was performed at 0, 1, 3, 5, 7 and 9 days. Results indicated that the expression of many drought stress-responsive genes and abscisic acid biosynthesis-related genes was differentially regulated in roots and shoots from days 3 to 9. The expression of cellular and metabolic process-related genes was up-regulated at an earlier time-point in roots than in shoots. In this regard, the expression of genes involved in oxidative signaling, chromatin structure, and cell wall modification also increased significantly in roots compared to shoots. Moreover, the increased expression of genes involved in the transport of amino acids and other solutes; including malate, iron, and sulfur, was observed in roots during the early time points following the initiation of the drought stress. These data suggest that plants may utilize these signaling channels and metabolic adjustments as adaptive responses in the early stages of a drought stress. Collectively, the results of the present study increases our understanding of the differences pertaining to the molecular mechanisms occurring in roots versus shoots in response to a drought stress. Furthermore, these findings also aid in the selection of novel genes and promoters that can be used to potentially produce crop plants with increased drought tolerance.

  12. The effects of increased phosphorus application on shoot dry matter ...

    African Journals Online (AJOL)

    The effects of increased phosphorus application on shoot dry matter, shoot P and Zn concentrations in wheat ( Triticum durum L.) and maize ( Zea mays L.)wheat ( Triticum durum L.) and maize ( Zea mays L.) grown in a calcareous soil.

  13. Uptake of polychlorinated biphenyls and organochlorine pesticides from soil and air into radishes (Raphanus sativus)

    Energy Technology Data Exchange (ETDEWEB)

    Mikes, Ondrej; Cupr, Pavel [RECETOX, Research Centre for Environmental Chemistry and Ecotoxicology, Masaryk University, Kamenice 126/3, 625 00 Brno (Czech Republic); Trapp, Stefan [Department of Environmental Engineering, Technical University of Denmark, Miljoevej 113, DK-2800 Kgs. Lyngby (Denmark); Klanova, Jana [RECETOX, Research Centre for Environmental Chemistry and Ecotoxicology, Masaryk University, Kamenice 126/3, 625 00 Brno (Czech Republic)], E-mail: klanova@recetox.muni.cz

    2009-02-15

    Uptake of organochlorine pesticides and polychlorinated biphenyls from soil and air into radishes was measured at a heavily contaminated field site. The highest contaminant concentrations were found for DDT and its metabolites, and for {beta}-hexachlorocyclohexane. Bioconcentration factor (BCF, defined as a ratio between the contaminant concentration in the plant tissue and concentration in soil) was determined for roots, edible bulbs and shoots. Root BCF values were constant and not correlated to log K{sub OW}. A negative correlation between BCF and log K{sub OW} was found for edible bulbs. Shoot BCF values were rather constant and varied between 0.01 and 0.22. Resuspended soil particles may facilitate the transport of chemicals from soil to shoots. Elevated POP concentrations found in shoots of radishes grown in the control plot support the hypothesis that the uptake from air was more significant for shoots than the one from soil. The uptake of POPs from air was within the range of theoretical values predicted from log K{sub OA}. - Uptake from air represented for majority of persistent organochlorines a dominant pathway into shoots while uptake from soil was dominant for roots.

  14. Optimization of aerodynamic form of projectile for solving the problem of shooting range increasing

    Science.gov (United States)

    Lipanov, Alexey M.; Korolev, Stanislav A.; Rusyak, Ivan G.

    2017-10-01

    The article is devoted to the development of methods for solving the problem of external ballistics using a more complete system of motion equation taken into account the rotation and oscillation about the mass center and using aerodynamic coefficients of forces and moments which are calculated on the basis of modeling the hydrodynamics of flow around the projectile. Developed methods allows to study the basic ways of increasing the shooting range or artillery.

  15. Consideration on the delay of radiocesium concentration decrease in bamboo shoots

    International Nuclear Information System (INIS)

    Tagami, Keiko; Uchida, Shigeo

    2012-01-01

    After the large releases of radionuclides due to the nuclear power plant accident in March 2011, trees in wide areas were directly contaminated. The contaminated leaves (mostly ever green trees) fell in the late spring to early summer, newly emerged leaves contained some radiocesium which were translocated from tree branches and trunks, and from soil through roots. The concentrations of radiocesium in tree leaves are decreasing due to dilution effect. However, for the case of bamboo shoots, decrease in radiocesium concentration was not observed in some areas when 2011 and 2012 samples were compared. In order to understand the fate of radiocesium in bamboos, 137 Cs concentration changes in leaves and branches from bamboos and litter layer and soil samples in a bamboo forest were measured. It was found that the concentration was higher in the following order: litter > leaves > branches > soil on 9 May 2011, however, the order changed to litter > soil >> leaves, branches on 20 October 2011. Removal of contaminated leaves from the bamboo trees and decomposition of the litter layer to soil organic matter was suggested from the results. Since the root zone of bamboo shoots was in the soil organic layer, radiocesium was taken up through roots to the shoots, and thus the concentration would be high. (author)

  16. Potential for phytoextraction of PCBs from contaminated soils using weeds.

    Science.gov (United States)

    Ficko, Sarah A; Rutter, Allison; Zeeb, Barbara A

    2010-07-15

    A comprehensive investigation of the potential of twenty-seven different species of weeds to phytoextract polychlorinated biphenyls (PCBs) from contaminated soil was conducted at two field sites (Etobicoke and Lindsay) in southern Ontario, Canada. Soil concentrations were 31 microg/g and 4.7 microg/g at each site respectively. All species accumulated PCBs in their root and shoot tissues. Mean shoot concentrations at the two sites ranged from 0.42 microg/g for Chenopodium album to 35 microg/g for Vicia cracca (dry weight). Bioaccumulation factors (BAF=[PCB](plant tissue)/[PCB](mean soil)) at the two sites ranged from 0.08 for Cirsium vulgare to 1.1 for V. cracca. Maximum shoot extractions were 420 microg for Solidago canadensis at the Etobicoke site, and 120 microg for Chrysanthemum leucanthemum at the Lindsay site. When plant density was taken into account with a theoretical density value, seventeen species appeared to be able to extract a similar or greater quantity of PCBs into the shoot tissue than pumpkins (Curcurbita pepo ssp. pepo) which are known PCB accumulators. Therefore, some of these weed species are promising candidates for future phytoremediation studies. Crown Copyright 2010. Published by Elsevier B.V. All rights reserved.

  17. Lead poisoning in shooting-range workers in Gauteng Province ...

    African Journals Online (AJOL)

    Background. Lead exposure constitutes a major public health concern globally. Relative to developed nations, lead exposure is understudied and poorly addressed in Africa, and there is a dearth of information available to inform lead poisoning prevention strategies, even in highrisk groups such as workers in shooting ...

  18. Initiation and growth of shoots of Gongronema latifolia Benth stem ...

    African Journals Online (AJOL)

    There was significant reduction in number of days to shoot initiation and growth in sawdust medium in the wet season. Sawdust and soil gave a better performance of the cuttings in opening of apical buds, initiation of shoots, percentage of rooted cuttings, number of vines, vine length and number of opposite leaves on vines ...

  19. Tea shoot production in relation to rainfall, solar radiation, and temperature in Pagilaran tea estate, Batang

    International Nuclear Information System (INIS)

    Yudono, P.

    2000-01-01

    Tea shoot production pattern in PT Pagilaran tea estate, Batang, is studied in relation to rainfall, solar radiation, and temperature. Pagilaran tea estate is located at 700-1,500 m above the sea level, with temperature of 15-30 deg. C and rainfall ranging from 4,500 mm to 7,000 mm per year. However, the area is also characterized by two up to three dry months for every three years. Monthly data of rainfall, solar radiation, and temperature were collected and were related to tea shoot production using correlation and regression analysis. The results indicated that there was no significant different pattern of tea shoot production form the three estate units (Kayulandak, Pagilaran, and Andongsili). Monthly shoots production increases during October up to December, and then goes down in January up to February. It fluctuated at a lesser degree in the upper units (Kayulandak and Andongsili) which might be attributed to better soil moisture available in the area. They are right below a forests area which understandably serves as rainfall catchment area and maintains soil moisture of the area below in a better condition. Weak to moderate correlation was obtained when monthly tea shoot production was correlated to amount of rainfall (r = -0.3771), days of rainfall (r = -0.3512), maximum temperature (r = -0.3502), minimum temperature (r = -0.2786), and solar radiation (r=0.6607) of the same month. On regressing monthly tea shoot production to those variables, rainfall and duration of solar radiation turned out to be the two significant factors through the following equation y = 759.5616-0.1802 xi-1 + 0.1057 xi-2 + 0.5239 zi-1 (R at the power of 2 = 0.3398), where y = tea shoots production, x=amount of monthly rainfall, z=duration of solar radiation, and i refer to month [in

  20. Antimony sinks in the weathering crust of bullets from Swiss shooting ranges

    International Nuclear Information System (INIS)

    Ackermann, Sonia; Giere, Reto; Newville, Matthew; Majzlan, Juraj

    2009-01-01

    Shooting ranges represent sites heavily polluted by Pb, Sb, Cu, Ni, and Zn, which are released during the weathering of bullets. The pristine bullets are made of a Pb-Sb core, Fe mantle, and minor amounts of Cu, Ni, and Zn in an interlayer between the core and mantle. At two selected sampling sites (Losone and Lucerne, both in Switzerland), corroding bullets were collected to determine the sinks of Sb within the weathering crust of the bullets. Bulk Sb concentrations in the crust were found to be as high as 1.3 wt.%. The oxalate-extractable fraction of Fe showed that the amorphous Fe oxides (e.g., ferrihydrite) prevail over goethite and lepidocrocite, which were identified by bulk X-ray diffraction experiments. Crystalline Pb phases are litharge (only found by X-ray diffraction) and cerussite, which result from weathering of the Pb core. No distinct Sb minerals were identified by X-ray diffraction. Investigations with electron microprobe (EMP) showed that Sb is mostly accumulated in those regions in the weathering crust where there is also a high concentration of Fe. In the weathering crust from Losone, such Fe-rich regions with Sb are represented by material that cements or rims silicate mineral grains. The cement was identified as lepidocrocite by micro-Raman analysis. At Lucerne, Sb is found in Fe-oxide aggregates, in sawdust particles where it may be bound to organic matter, or in aggregates enriched in Pb and depleted in Fe. Bulk EXAFS experiments suggested that the Fe oxides are the most important sink for Sb. Our modelling of Sb next-nearest neighbours suggests two types of inner-sphere complexes on the surfaces of Fe oxides. These are edge- and corner-sharing adsorption complexes. Hence, the predominant sink of Sb in the weathering crust of the bullets at the selected shooting ranges is Fe oxides, amorphous or crystalline

  1. Arbuscular mycorrhizal fungi can decrease the uptake of uranium by subterranean clover grown at high levels of uranium in soil

    International Nuclear Information System (INIS)

    Rufyikiri, Gervais; Huysmans, Lien; Wannijn, Jean; Hees, May van; Leyval, Corinne; Jakobsen, Iver

    2004-01-01

    Subterranean clover inoculated or not with the arbuscular mycorrhizal (AM) fungus Glomus intraradices was grown on soil containing six levels of 238 U in the range 0-87 mg kg -1 . Increasing U concentration in soil enhanced the U concentration in roots and shoots of both mycorrhizal and nonmycorrhizal plants but had no significant effects on plant dry matter production or root AM colonization. Mycorrhizas increased the shoot dry matter and P concentration in roots and shoots, while in most cases, it decreased the Ca, Mg and K concentrations in plants. The AM fungus influenced U concentration in plants only in the treatment receiving 87 mg U kg -1 soil. In this case, U concentration in shoots of nonmycorrhizal plants was 1.7 times that of shoots of mycorrhizal plants. These results suggested that mycorrhizal fungi can limit U accumulation by plants exposed to high levels of U in soil. - Plant mycorrhization may decrease U concentration in shoots of plants grown at high level of U in soil

  2. Lead and Antimony Speciation in Shooting Range Soils: Molecular Scale Analysis, Temporal Trends and Mobility

    Science.gov (United States)

    2017-11-20

    years is shown in Figure 12. The steel and Cu jacket partially separated from one another, leaving the Pb/Sb slug exposed. While Pb comprises the bulk...crust appears to act as a cement between the bullet fragments and surrounding soil particles as well as between individual soil particles. Similar...few hundred micrometers from the weathering crust (Vantelon et al., 2005). The distribution of Sb is discontinuous in the bullet alloy and cemented

  3. Bioavailability of barium to plants and invertebrates in soils contaminated by barite.

    Science.gov (United States)

    Lamb, Dane T; Matanitobua, Vitukawalu P; Palanisami, Thavamani; Megharaj, Mallavarapu; Naidu, Ravi

    2013-05-07

    Barium (Ba) is a nonessential element to terrestrial organisms and is known to be toxic at elevated concentrations. In this study, the bioavailability and toxicity of Ba in barite (BaSO4) contaminated soils was studied using standard test organisms (Lactuca sativa L. "Great Lakes", Eisenia fetida). Contamination resulted from barite mining activities. Barium concentrations in contaminated soils determined by X-ray fluorescence were in the range 0.13-29.2%. Barite contaminated soils were shown to negatively impact both E. fetida and L. sativa relative to control soil. For E. fetida, pore-water concentrations and acid extractable Ba were linearly related to % body weight loss. In L. sativa, pore-water Ba and exchangeable Ba were both strongly related to shoot Ba and shoot biomass production. A negative linear relationship was observed between shoot Ba content and shoot weight (P Barium concentrations in pore-water were lower than predicted from barite solubility estimates but strongly related to exchangeable Ba, indicating an influence of ion exchange on Ba solubility and toxicity to E. fetida and L. sativa.

  4. Microbiome and ecotypic adaption of Holcus lanatus (L.) to extremes of its soil pH range, investigated through transcriptome sequencing.

    Science.gov (United States)

    Young, Ellen; Carey, Manus; Meharg, Andrew A; Meharg, Caroline

    2018-03-20

    Plants can adapt to edaphic stress, such as nutrient deficiency, toxicity and biotic challenges, by controlled transcriptomic responses, including microbiome interactions. Traditionally studied in model plant species with controlled microbiota inoculation treatments, molecular plant-microbiome interactions can be functionally investigated via RNA-Seq. Complex, natural plant-microbiome studies are limited, typically focusing on microbial rRNA and omitting functional microbiome investigations, presenting a fundamental knowledge gap. Here, root and shoot meta-transcriptome analyses, in tandem with shoot elemental content and root staining, were employed to investigate transcriptome responses in the wild grass Holcus lanatus and its associated natural multi-species eukaryotic microbiome. A full factorial reciprocal soil transplant experiment was employed, using plant ecotypes from two widely contrasting natural habitats, acid bog and limestone quarry soil, to investigate naturally occurring, and ecologically meaningful, edaphically driven molecular plant-microbiome interactions. Arbuscular mycorrhizal (AM) and non-AM fungal colonization was detected in roots in both soils. Staining showed greater levels of non-AM fungi, and transcriptomics indicated a predominance of Ascomycota-annotated genes. Roots in acid bog soil were dominated by Phialocephala-annotated transcripts, a putative growth-promoting endophyte, potentially involved in N nutrition and ion homeostasis. Limestone roots in acid bog soil had greater expression of other Ascomycete genera and Oomycetes and lower expression of Phialocephala-annotated transcripts compared to acid ecotype roots, which corresponded with reduced induction of pathogen defense processes, particularly lignin biosynthesis in limestone ecotypes. Ascomycota dominated in shoots and limestone soil roots, but Phialocephala-annotated transcripts were insignificant, and no single Ascomycete genus dominated. Fusarium-annotated transcripts were

  5. Plantlets from encapsulated shoot buds of Catalpa ovata G. Don

    Directory of Open Access Journals (Sweden)

    Halina Wysokińska

    2014-01-01

    Full Text Available Shoot buds isolated from in vitro shoot cultures of Catalpa ovata G. Don were encapsulated using 3% sodium alginate with sucrose (3% and 50 mM calcium chloride. The morphogenic response of encapsulated buds was affected by such factors, like composition of the media and the presence of growth regulators. The highest frequency of plantlet germination from encapsulated buds (70% within 4 weeks was obtained on Woody Plant medium (WP (Lloyd and McCown 1980 containing indole-3-butyric acid (IBA (1 mg/l. The process was substantially inhibited by cold-storage (4oC of encapsulated buds. In this case, the frequency response ranged from 3% to 22% dependent on storage period (28 or 42 days and the presence of the paraffin coat covering the alginate capsules. The plantlets developed from both unstored and stored encapsulated buds of C. ovata were transplanted to soil and grew in pots to phenotypically normal plants.

  6. Morphological and functional responses of a metal-tolerant sunflower mutant line to a copper-contaminated soil series.

    Science.gov (United States)

    Kolbas, Aliaksandr; Kolbas, Natallia; Marchand, Lilian; Herzig, Rolf; Mench, Michel

    2018-04-02

    The potential use of a metal-tolerant sunflower mutant line for biomonitoring Cu phytoavailability, Cu-induced soil phytotoxicity, and Cu phytoextraction was assessed on a Cu-contaminated soil series (13-1020 mg Cu kg -1 ) obtained by fading a sandy topsoil from a wood preservation site with a similar uncontaminated soil. Morphological and functional plant responses as well as shoot, leaf, and root ionomes were measured after a 1-month pot experiment. Hypocotyl length, shoot and root dry weight (DW) yields, and leaf area gradually decreased as soil Cu exposure rose. Their dose-response curves (DRC) plotted against indicators of Cu exposure were generally well fitted by sigmoidal curves. The half-maximal effective concentration (EC 50 ) of morphological parameters ranged between 203 and 333 mg Cu kg -1 soil, corresponding to 290-430 μg Cu L -1 in the soil pore water, and 20 ± 5 mg Cu kg -1 DW in the shoots. The EC 10 for shoot Cu concentration (13-15 mg Cu kg -1 DW) coincided to 166 mg Cu kg -1 soil. Total chlorophyll content and total antioxidant capacity (TAC) were early biomarkers (EC 10 : 23 and 51 mg Cu kg -1 soil). Their DRC displayed a biphasic response. Photosynthetic pigment contents, e.g., carotenoids, correlated with TAC. Ionome was changed in Cu-stressed roots, shoots, and leaves. Shoot Cu removal peaked roughly at 280 μg Cu L -1 in the soil pore water.

  7. Copper bioavailability and extractability as related to chemical properties of contaminated soils from a vine-growing area

    International Nuclear Information System (INIS)

    Chaignon, V.; Sanchez-Neira, I.; Herrmann, P.; Jaillard, B.; Hinsinger, P.

    2003-01-01

    Root Cu concentration is a good indicator of soil Cu bioavailability. - Vineyard soils have been contaminated by Cu as a consequence of the long-term use of Cu salts as fungicides against mildew. This work aimed at identifying which soil parameters were the best related to Cu bioavailability, as assessed by measuring the concentrations of Cu in shoots and roots of tomato cropped (in lab conditions) over a range of 29 (24 calcareous and five acidic) Cu-contaminated topsoils from a vine-growing area (22-398 mg Cu kg -1 ). Copper concentrations in tomato shoots remained in the adequate range and were independent of soil properties and soil Cu content. Conversely, strong, positive correlations were found between root Cu concentration, total soil Cu, EDTA- or K-pyrophosphate-extractable Cu and organic C contents in the 24 calcareous soils, suggesting a prominent role of organic matter in the retention and bioavailability of Cu. Such relations were not observed when including the five acidic soils in the investigated population, suggesting a major pH effect. Root Cu concentration appeared as a much more sensitive indicator of soil Cu bioavailability than shoot Cu concentration. Simple extractions routinely used in soil testing procedures (total and EDTA-extractable Cu) were adequate indicators of Cu bioavailability for the investigated calcareous soils, but not when different soil types were considered (e.g. acidic versus calcareous soils)

  8. Shoot and root responses of Trifolium vesiculosum to boron fertilization in an acidic Brazilian soil

    Directory of Open Access Journals (Sweden)

    Nerilde Favaretto

    2007-07-01

    Full Text Available To analyze the influence of boron fertilization on shoot and root growth of Trifolium vesiculosum (arrowleaf clover, an acid soil profile (60 cm depth with 67% Al saturation was recreated in a column (three layers of 20 cm each. Lime and fertilizer (P and K were incorporated into the top 20 cm. The treatments consisted of six boron rates where boric acid was mixed throughout the profile. Addition of boron to soil with low pH and high Al increased the root and shoot growth, independent of the rate applied. Boron inhibited Al toxicity, but no effect was observed in the root length when Al was not present in the soil. It was also observed that there was more root growth below the plow layer (0-20 cm, suggesting better root distribution in the soil profile which could be important for the plant growth, especially under drought conditions.Estudos têm mostrado que o boro (B afeta o crescimento das raízes em solo ácido reduzindo a toxidez do alumínio (Al. Para analisar a influência do boro no crescimento da parte aérea e raízes do Trifolium Vesiculosum (trevo vesiculoso um perfil de solo ácido (60 cm de profundidade com 67% de saturação de Al foi recriado em uma coluna (três camadas com 20 cm cada. Calcário e adubos (P e K foram incorporados na camada de 0-20 cm. Os tratamentos consistiram de seis doses de boro sendo o ácido bórico incorporado em todo o perfil. A adubação com boro em solo com baixo pH e elevado Al aumentou o crescimento da parte aérea e raízes, no entanto, independente da dose aplicada. Boro pode inibir a toxidez de Al, porém não observou-se efeito no comprimento de raízes sem a presença de Al no solo. Observou-se também um grande aumento no crescimento de raízes abaixo da camada arável (0-20 cm, fornecendo uma melhor distribuição de raízes no perfil do solo, o que pode ser importante para o crescimento da planta especialmente em condição de seca.

  9. Phyto extraction Of Cadmium And Zinc From Contaminated Soils

    International Nuclear Information System (INIS)

    Lotfy, S.M.; Mostafa, A.Z.; Abdel Sabour, M. F.

    2012-01-01

    A trial was made to study the use of different plant species to extract heavy metals out of contaminated soils. Four Kg of each air-dried surface soil sample (0-20 cm) were packed in plastic containers in three replicates. Five plant species tested in this study namely, Panikum (Panicum antidotal) and napier grass (Bennisetum purpureum), squash (Cucurbita pepo), cotton (Gossypium hirsutum), sunflower (Helianthus annuus); were grown on two different polluted soil types (Mostorud Clayey soil, irrigated with contaminated water for more than 30 years and El-Gabal EL-Asfar sandyloam soil, subjected to sewage effluent irrigation for more than 50 years) in a complete randomized block experimental design to study the mobility and fate of selected heavy metals and evaluate the efficiency of the tested plant species to extract Cadmium and Zinc out of polluted soils. Data indicated that sunflower and cotton shoots accumulated the highest Cd content among the five tested plant species, Shoot concentrations of Cd were as high as 9.6 mg/kg dry matter of sunflower, followed by panikum and napier grass, cotton then squash with a range of Cd between 9.6 to 1.6 mg/kg dry matter in case of the alluvium soil. However in the sandy soil, sunflower Cd -shoots were > penakium> napier grass > cotton> Squash with a lower order of magnitude which could be explained by the lower Cd -content in sandy soil compared to the alluvial soil .Calculation of recovery percentage based on Cd and Zn removed from the soil after cultivation ranged between 5.9 to 27.4 % and 16.1 to 49.1% of total initial Cd and Zn, Respectively. However, The percentage of Cd and Zn -removed by plant shoots from the initial total varied between 27.6 to 37.5% and 25.3 and 36.8 % of the removed Cd and Zn, Respectively, whereas the lowest values were observed in case of squash for Cd and Zn. As expected plant roots exhibited higher Cd and Zn accumulation than in shoots by 2-3 folds. Sunflower roots showed the highest Cd

  10. Radiographing roots and shoots

    International Nuclear Information System (INIS)

    Shariffah Noor Khamseah Al Idid

    1985-01-01

    The effect of seed orientation on germination time and on shoot and root growth patterns is studied. Neutron radiography is used to observe the development of 4 types of plants, maize, greenpea, soya bean and padi. These plants were grown in varying orientations; sand sizes, sand thicknesses, and level of water content. Radiography of the seeds and plants were obtained for time exposure ranging from 3-12 hours and at reactor thermal power level, ranging from 500-750 kilowatts. Results obtained showed that seeds planted in varying orientations need different length of time for shoot emergence. Neutron radiography is now developed to other areas of non-industrial applications in Malaysia. (A.J.)

  11. Influence of soil properties and phosphate addition on arsenic uptake from polluted soils by velvetgrass (Holcus lanatus).

    Science.gov (United States)

    Lewińska, K; Karczewska, A

    2013-01-01

    Four kinds of soil material were used in a pot experiment with velvetgrass (Holcus lanatus). Two unpolluted soils: sand (S) and loam (L) were spiked with sodium arsenite (As II) and arsenate (As V), to obtain total arsenic (As) concentrations of 500 mg As kg(-1). Two other soils (ZS I, ZS III), containing 3320 and 5350 mg As kg(-1), were collected from Zloty Stok where gold and arsenic ores were mined and processed for several centuries. The effects of phosphate addition on plants growth and As uptake were investigated. Phosphate was applied to soils in the form of NH4H2PO4 at the rate 0.2 g P/kg. Average concentrations of arsenic in the shoots of velvetgrass grown in spiked soils S and L without P amendment were in the range 18-210 mg As kg(-1) d.wt., whereas those in plants grown on ZS I and ZS II soils were considerably lower, and varied in the range 11-52 mg As kg(-1) d.wt. The addition of phosphate caused a significant increase in plant biomass and therefore the total amounts of As taken up by plants, however, the differences in As concentrations in the shoots of velvetgrass amended and non-amended with phosphate were not statistically significant.

  12. Improvement of the soil nitrogen content and maize growth by earthworms and arbuscular mycorrhizal fungi in soils polluted by oxytetracycline.

    Science.gov (United States)

    Cao, Jia; Wang, Chong; Ji, Dingge

    2016-11-15

    Interactions between earthworms (Eisenia fetida) and arbuscular mycorrhizal fungi (Rhizophagus intraradices, AM fungi) have been suggested to improve the maize nitrogen (N) content and biomass and were studied in soils polluted by oxytetracycline (OTC). Maize was planted and amended with AMF and/or earthworms (E) in the soil with low (1mgkg(-1) soil DM) or high (100mgkg(-1) soil DM) amounts of OTC pollution in comparison to soil without OTC. The root colonization, shoot and root biomass, shoot and root N contents, soil nitrogen forms, ammonia-oxidizing bacteria (AOB) and archaea (AOA) were measured at harvest. The results indicated that OTC decreased maize shoot and root biomass (psoil urease activity and AOB and AOA abundance, which resulted in a lower N availability for maize roots and shoots. There was a significant interaction between earthworms and AM fungi on the urease activity in soil polluted by OTC (ppolluted soil by increasing the urease activity and relieving the stress from OTC on the soil N cycle. AM fungi and earthworms interactively increased maize shoot and root biomass (ppolluted soils through their regulation of the urease activity and the abundance of ammonia oxidizers, resulting in different soil NH4(+)-N and NO3(-)-N contents, which may contribute to the N content of maize shoots and roots. Earthworms and AM fungi could be used as an efficient method to relieve the OTC stress in agro-ecosystems. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Assessing Lead, Nickel, and Zinc Pollution in Topsoil from a Historic Shooting Range Rehabilitated into a Public Urban Park.

    Science.gov (United States)

    Urrutia-Goyes, Ricardo; Argyraki, Ariadne; Ornelas-Soto, Nancy

    2017-06-30

    Soil contamination is a persistent problem in the world. The redevelopment of a site with a historical deposition of metals might conceal the threat of remaining pollution, especially when the site has become a public place. In this study, human health risk assessment is performed after defining the concentrations of Pb, Ni, and Zn in the topsoil of a former shooting range rehabilitated into a public park in the Municipality of Kesariani (Athens, Greece). A methodology that uses inductively coupled plasma mass spectrometry (ICP-MS, 13 samples), another that uses portable X-ray fluorescence (XRF) following a dense sample design (91 samples), and a hybrid approach that combines both, were used to obtain the concentrations of the trace elements. The enrichment factor and geoacummulation index were calculated to define the degree of pollution of the site. The hazard quotient and cancer risk indicators were also computed to find the risk to which the population is exposed. The present study reveals high non-carcinogenic health risk due to Pb pollution with ingestion as the main exposure pathway. The carcinogenic risk for Pb is within tolerable limits, but the definition of land use might alter such a statement. Lastly, regarding Ni and Zn, the site is unpolluted and there is insignificant carcinogenic and non-carcinogenic risks.

  14. Mechanisms of waterlogging tolerance in wheat - a review of root and shoot physiology

    DEFF Research Database (Denmark)

    Herzog, Max; Striker, Gustavo G; Colmer, Timothy D

    2016-01-01

    :shoot ratio. Genotypes differ in seminal root anoxia tolerance, but mechanisms remain to be established; ethanol production rates do not explain anoxia tolerance. Root tip survival is short-term, and thereafter, seminal root re-growth upon re-aeration is limited. Genotypes differ in adventitious root numbers....... Although photosynthesis declines, sugars typically accumulate in shoots of waterlogged plants. Mn or Fe toxicity might occur in shoots of wheat on strongly acidic soils, but probably not more widely. Future breeding for waterlogging tolerance should focus on root internal aeration and better N...

  15. Effect of Soil Aging on the Phytoremediation Potential of Zea mays in Chromium and Benzo[a]Pyrene Contaminated Soils.

    Science.gov (United States)

    Chigbo, Chibuike

    2015-06-01

    This study compared the phytoremediation potential of Zea mays in soil either aged or freshly amended with chromium (Cr) and benzo[a]pyrene (B[a]P). Z. mays showed increased shoot biomass in aged soils than in freshly spiked soils. The shoot biomass in contaminated soils increased by over 50% in aged soil when compared to freshly amended soils, and over 29% more Cr was accumulated in the shoot of Z. mays in aged soil than in freshly amended soil. Planting Z. mays in aged soil helped in the dissipation of more than 31% B[a]P than in freshly spiked soil, but in the absence of plants, there seemed to be no difference between the dissipation rates of B[a]P in freshly and aged co-contaminated soil. Z. mays seemed to enhance the simultaneous removal of Cr and B[a]P in aged soil than in freshly spiked soil and hence can be a good plant choice for phytoremediation of co-contaminated soils.

  16. Shooting Mechanisms in Nature: A Systematic Review.

    Directory of Open Access Journals (Sweden)

    Aimée Sakes

    Full Text Available In nature, shooting mechanisms are used for a variety of purposes, including prey capture, defense, and reproduction. This review offers insight into the working principles of shooting mechanisms in fungi, plants, and animals in the light of the specific functional demands that these mechanisms fulfill.We systematically searched the literature using Scopus and Web of Knowledge to retrieve articles about solid projectiles that either are produced in the body of the organism or belong to the body and undergo a ballistic phase. The shooting mechanisms were categorized based on the energy management prior to and during shooting.Shooting mechanisms were identified with projectile masses ranging from 1·10-9 mg in spores of the fungal phyla Ascomycota and Zygomycota to approximately 10,300 mg for the ballistic tongue of the toad Bufo alvarius. The energy for shooting is generated through osmosis in fungi, plants, and animals or muscle contraction in animals. Osmosis can be induced by water condensation on the system (in fungi, or water absorption in the system (reaching critical pressures up to 15.4 atmospheres; observed in fungi, plants, and animals, or water evaporation from the system (reaching up to -197 atmospheres; observed in plants and fungi. The generated energy is stored as elastic (potential energy in cell walls in fungi and plants and in elastic structures in animals, with two exceptions: (1 in the momentum catapult of Basidiomycota the energy is stored in a stalk (hilum by compression of the spore and droplets and (2 in Sphagnum energy is mainly stored in compressed air. Finally, the stored energy is transformed into kinetic energy of the projectile using a catapult mechanism delivering up to 4,137 J/kg in the osmotic shooting mechanism in cnidarians and 1,269 J/kg in the muscle-powered appendage strike of the mantis shrimp Odontodactylus scyllarus. The launch accelerations range from 6.6g in the frog Rana pipiens to 5,413,000g in

  17. Jatropha curcas L. Root Structure and Growth in Diverse Soils

    Science.gov (United States)

    Valdés-Rodríguez, Ofelia Andrea; Sánchez-Sánchez, Odilón; Pérez-Vázquez, Arturo; Caplan, Joshua S.; Danjon, Frédéric

    2013-01-01

    Unlike most biofuel species, Jatropha curcas has promise for use in marginal lands, but it may serve an additional role by stabilizing soils. We evaluated the growth and structural responsiveness of young J. curcas plants to diverse soil conditions. Soils included a sand, a sandy-loam, and a clay-loam from eastern Mexico. Growth and structural parameters were analyzed for shoots and roots, although the focus was the plasticity of the primary root system architecture (the taproot and four lateral roots). The sandy soil reduced the growth of both shoot and root systems significantly more than sandy-loam or clay-loam soils; there was particularly high plasticity in root and shoot thickness, as well as shoot length. However, the architecture of the primary root system did not vary with soil type; the departure of the primary root system from an index of perfect symmetry was 14 ± 5% (mean ± standard deviation). Although J. curcas developed more extensively in the sandy-loam and clay-loam soils than in sandy soil, it maintained a consistent root to shoot ratio and root system architecture across all types of soil. This strong genetic determination would make the species useful for soil stabilization purposes, even while being cultivated primarily for seed oil. PMID:23844412

  18. Jatropha curcas L. root structure and growth in diverse soils.

    Science.gov (United States)

    Valdés-Rodríguez, Ofelia Andrea; Sánchez-Sánchez, Odilón; Pérez-Vázquez, Arturo; Caplan, Joshua S; Danjon, Frédéric

    2013-01-01

    Unlike most biofuel species, Jatropha curcas has promise for use in marginal lands, but it may serve an additional role by stabilizing soils. We evaluated the growth and structural responsiveness of young J. curcas plants to diverse soil conditions. Soils included a sand, a sandy-loam, and a clay-loam from eastern Mexico. Growth and structural parameters were analyzed for shoots and roots, although the focus was the plasticity of the primary root system architecture (the taproot and four lateral roots). The sandy soil reduced the growth of both shoot and root systems significantly more than sandy-loam or clay-loam soils; there was particularly high plasticity in root and shoot thickness, as well as shoot length. However, the architecture of the primary root system did not vary with soil type; the departure of the primary root system from an index of perfect symmetry was 14 ± 5% (mean ± standard deviation). Although J. curcas developed more extensively in the sandy-loam and clay-loam soils than in sandy soil, it maintained a consistent root to shoot ratio and root system architecture across all types of soil. This strong genetic determination would make the species useful for soil stabilization purposes, even while being cultivated primarily for seed oil.

  19. Jatropha curcas L. Root Structure and Growth in Diverse Soils

    Directory of Open Access Journals (Sweden)

    Ofelia Andrea Valdés-Rodríguez

    2013-01-01

    Full Text Available Unlike most biofuel species, Jatropha curcas has promise for use in marginal lands, but it may serve an additional role by stabilizing soils. We evaluated the growth and structural responsiveness of young J. curcas plants to diverse soil conditions. Soils included a sand, a sandy-loam, and a clay-loam from eastern Mexico. Growth and structural parameters were analyzed for shoots and roots, although the focus was the plasticity of the primary root system architecture (the taproot and four lateral roots. The sandy soil reduced the growth of both shoot and root systems significantly more than sandy-loam or clay-loam soils; there was particularly high plasticity in root and shoot thickness, as well as shoot length. However, the architecture of the primary root system did not vary with soil type; the departure of the primary root system from an index of perfect symmetry was 14±5% (mean ± standard deviation. Although J. curcas developed more extensively in the sandy-loam and clay-loam soils than in sandy soil, it maintained a consistent root to shoot ratio and root system architecture across all types of soil. This strong genetic determination would make the species useful for soil stabilization purposes, even while being cultivated primarily for seed oil.

  20. Shoot and root biomass allocation and competitive hierarchies of ...

    African Journals Online (AJOL)

    Shoot and root biomass allocation and competitive hierarchies of four South African grass species on light, soil resources and cutting gradients. ... Aristida junciformis, produced nearly double the biomass of taller species such as Hyparrhenia hirta and Eragrostis curvula in the low-nutrient treatments, with the reverse being ...

  1. Arbuscular mycorrhizal strategy for zinc mycoremediation and diminished translocation to shoots and grains in wheat

    Science.gov (United States)

    2017-01-01

    Mycoremediation is an on-site remediation strategy, which employs fungi to degrade or sequester contaminants from the environment. The present work focused on the bioremediation of soils contaminated with zinc by the use of a native mycorrhizal fungi (AM) called Funneliformis geosporum (Nicol. & Gerd.) Walker & Schüßler. Experiments were performed using Triticum aestivum L. cv. Gemmeza-10 at different concentrations of Zn (50, 100, 200 mg kg-1) and inoculated with or without F. geosporum. The results showed that the dry weight of mycorrhizal wheat increased at Zn stressed plants as compared to the non-Zn-stressed control plants. The concentrations of Zn also had an inhibitory effect on the yield of dry root and shoot of non-mycorrhizal wheat. The photosynthetic pigment fractions were significantly affected by Zn treatments and mycorrhizal inoculation, where in all treatments, the content of the photosynthetic pigment fractions decreased as the Zn concentration increased in the soil. However, the level of minerals of shoots, roots, and grains was greatly influenced by Zn-treatment and by inoculation with F. geosporum. Treatment with Zn in the soil increased Cu and Zn concentrations in the root, shoot and grains, however, other minerals (P, S, K, Ca and Fe) concentration was decreased. Inoculation of wheat with AM fungi significantly reduced the accumulation of Zn and depressed its translocation in shoots and grains of wheat. In conclusion, inoculation with a native F. geosporum-improves yields of wheat under higher levels of Zn and is possible to be applied for the improvement of zinc contaminated soil. PMID:29145471

  2. Soybean growth on fly ash-amended strip mine soils

    Energy Technology Data Exchange (ETDEWEB)

    Fail, Jr, J L; Wochok, Z S

    1977-01-01

    The use of fly ash as an amendment for strip mine soils has been studied under field conditions. Soils ranging in pH from 4.0 to 6.0 were tested. The addition of fly ash in all cases was effective as an acid soil neutralizer and substantially enhanced the growth and development of all experimental plants. The parameters used in growth analyses were plant height, dry weight, root/shoot ratios, nodulation, pod production, and nitrogen fixing capacity for legumes.

  3. Studies on the tissue culture of Stevia rebaudiana and its components; (II). Induction of shoot primordia.

    Science.gov (United States)

    Miyagawa, H; Fujioka, N; Kohda, H; Yamasaki, K; Taniguchi, K; Tanaka, R

    1986-08-01

    Shoot primordia, which were able to propagate vegetatively with a very high rate and to redifferentiate easily to new plants, were induced from shoot tips of Stevia rebaudiana Bertoni on Gamborg B5 medium containing 6-benzylaminopurine (BAP) and alpha-naphthaleneacetic acid (NAA) under light. The propagation of the shoot primordia of Stevia rebaudiana is rapid, and they are highly stable in chromosome number and karyotype. The shoot primordia can propagate at a high rate for a long time without differentiation. At any time, the shoot primordia readily developed into plantlets with shoots and roots within 2 or 3 weeks in static culture on B5 medium containing 0.02 mg/l BAP and 2% sucrose. The plantlets were transplanted to sterilized soil to grow to normal adult plants.

  4. Variation in shoot tolerance mechanisms not related to ion toxicity in barley

    KAUST Repository

    Tilbrook, Joanne

    2017-09-27

    Soil salinity can severely reduce crop growth and yield. Many studies have investigated salinity tolerance mechanisms in cereals using phenotypes that are relatively easy to measure. The majority of these studies measured the accumulation of shoot Na+ and the effect this has on plant growth. However, plant growth is reduced immediately after exposure to NaCl before Na+ accumulates to toxic concentrations in the shoot. In this study, nondestructive and destructive measurements are used to evaluate the responses of 24 predominately Australian barley (Hordeum vulgare L.) lines at 0, 150 and 250mMNaCl. Considerable variation for shoot tolerance mechanisms not related to ion toxicity (shoot ion-independent tolerance) was found, withsome lines being able to maintain substantial growth rates under salt stress, whereas others stopped growing. Hordeum vulgare spp. spontaneum accessions and barley landraces predominantly had the best shoot ion independent tolerance, although two commercial cultivars, Fathom and Skiff, also had high tolerance. The tolerance of cv. Fathom may be caused by a recent introgression from H. vulgare L. spp. spontaneum. This study shows that the most salt-tolerant barley lines are those that contain both shoot ion-independent tolerance and the ability to exclude Na+ from the shoot (and thus maintain high K+: Na+ ratios).

  5. Variation in shoot tolerance mechanisms not related to ion toxicity in barley

    KAUST Repository

    Tilbrook, Joanne; Schilling, Rhiannon K.; Berger, Bettina; Garcia, Alexandre F.; Trittermann, Christine; Coventry, Stewart; Rabie, Huwaida; Brien, Chris; Nguyen, Martin; Tester, Mark A.; Roy, Stuart J.

    2017-01-01

    Soil salinity can severely reduce crop growth and yield. Many studies have investigated salinity tolerance mechanisms in cereals using phenotypes that are relatively easy to measure. The majority of these studies measured the accumulation of shoot Na+ and the effect this has on plant growth. However, plant growth is reduced immediately after exposure to NaCl before Na+ accumulates to toxic concentrations in the shoot. In this study, nondestructive and destructive measurements are used to evaluate the responses of 24 predominately Australian barley (Hordeum vulgare L.) lines at 0, 150 and 250mMNaCl. Considerable variation for shoot tolerance mechanisms not related to ion toxicity (shoot ion-independent tolerance) was found, withsome lines being able to maintain substantial growth rates under salt stress, whereas others stopped growing. Hordeum vulgare spp. spontaneum accessions and barley landraces predominantly had the best shoot ion independent tolerance, although two commercial cultivars, Fathom and Skiff, also had high tolerance. The tolerance of cv. Fathom may be caused by a recent introgression from H. vulgare L. spp. spontaneum. This study shows that the most salt-tolerant barley lines are those that contain both shoot ion-independent tolerance and the ability to exclude Na+ from the shoot (and thus maintain high K+: Na+ ratios).

  6. THE EFFICIENCY OF SHOOT AND PLANTLET FORMATION OF Cephaelis ipecacuanha AFTER THREE SUBCULTURES IN VITRO

    Directory of Open Access Journals (Sweden)

    Osmar Alves Lameira

    1994-12-01

    Full Text Available Multiple adventitious shoot formed from internodal segments of Cephaelis ipecacuanha cultured 25 days on Gamborg basal medium (GAMBORG et al., 1968 supplemented with 6.66mM 6-benzylaminopurine there was a maximum of nine shoots per segment and an average of five shoots per segment formed. The presence of gibberellic acid in the subculture media promoted shoot elongation in all treatments. The shoots attained 3cm in height and rooting of 100% after 35 days of culturing upon Murashige and Skoog's basal medium (MS, added with 4.92mM indole-3-butyric acid, 0.87m gibberellic acid and 0.1% activated charcoal. Further growth was accelerated after the transfer to 1/2 MS without growth regulators. Rooted plantlets transferred to potting soil could be successfully established.

  7. Shoot regeneration and embryogenesis in lily shoot tips cryopreserved by droplet vitrification

    Science.gov (United States)

    Shoot regeneration and embryogenesis were, for the first time, achieved directly in shoot tips of Lilium Oriental hybrid ‘Siberia’ following cryopreservation by droplet-vitrification. Shoot tips (2 mm in length) including 2-3 leaf primordia were excised from 4-week-old adventitious shoots directly r...

  8. Effect of Hormones on Direct Shoot Regeneration in Hypocotyl Explants of Tomato

    Directory of Open Access Journals (Sweden)

    Rizwan RASHID

    2010-03-01

    Full Text Available This study was conducted for developing a high frequency regeneration system in two genotypes of tomato (Lycopersicon esculentum Mill., �Punjab Upma� and �IPA-3� for direct shoot regeneration from hypocotyl explants. The explants were excised from in vitro tomato seedlings and cultured on MS medium supplemented with different concentrations and combinations of hormones. Direct regeneration was significantly influenced by the genotype hormones combination and concentrations. The MS medium supplemented with (Kinetin 0.5 mg/l and (BAP 0.5 mg/l was found optimum for inducing direct shoot regeneration and number of shoots per explant from hypocotyl explants on this medium. Shoot regeneration per cent in �Punjab Upma� and �IPA-3� per cent was recorded to be highest i.e (86.02 and (82.57 respectively. Besides this, average number shoots per explant was also highest i.e (3.16 in case of �Punjab Upma� and (2.93 in case of �IPA-3�. A significant decline was observed in percent shoot regeneration and average number of shoots per explant with increase in the hormonal concentration. Shoots were obtained and transferred to the elongation medium (MS + BAP 0.3 mg/l. Hundred per cent rooting was induced in separated shoots upon culturing on MS and � MS basal media. Hardening on moist cotton showed maximum plantlet survival rate in case of both genotypes. After hardening, plants were transferred to soil. Thus, a tissue culture base line was established in tomato for obtaining direct regeneration using hypocotyl as explants.

  9. Effect of Hormones on Direct Shoot Regeneration in Hypocotyl Explants of Tomato

    Directory of Open Access Journals (Sweden)

    Rizwan RASHID

    2010-03-01

    Full Text Available This study was conducted for developing a high frequency regeneration system in two genotypes of tomato (Lycopersicon esculentum Mill., Punjab Upma and IPA-3 for direct shoot regeneration from hypocotyl explants. The explants were excised from in vitro tomato seedlings and cultured on MS medium supplemented with different concentrations and combinations of hormones. Direct regeneration was significantly influenced by the genotype hormones combination and concentrations. The MS medium supplemented with (Kinetin 0.5 mg/l and (BAP 0.5 mg/l was found optimum for inducing direct shoot regeneration and number of shoots per explant from hypocotyl explants on this medium. Shoot regeneration per cent in Punjab Upma and IPA-3 per cent was recorded to be highest i.e (86.02 and (82.57 respectively. Besides this, average number shoots per explant was also highest i.e (3.16 in case of Punjab Upma and (2.93 in case of IPA-3. A significant decline was observed in percent shoot regeneration and average number of shoots per explant with increase in the hormonal concentration. Shoots were obtained and transferred to the elongation medium (MS + BAP 0.3 mg/l. Hundred per cent rooting was induced in separated shoots upon culturing on MS and MS basal media. Hardening on moist cotton showed maximum plantlet survival rate in case of both genotypes. After hardening, plants were transferred to soil. Thus, a tissue culture base line was established in tomato for obtaining direct regeneration using hypocotyl as explants.

  10. Tolerance to high soil temperature in foxtail millet (Setaria italica L.) is related to shoot and root growth and metabolism.

    Science.gov (United States)

    Aidoo, Moses Kwame; Bdolach, Eyal; Fait, Aaron; Lazarovitch, Naftali; Rachmilevitch, Shimon

    2016-09-01

    Roots play important roles in regulating whole-plant carbon and water relations in response to extreme soil temperature. Three foxtail millet (Setaria italica L.) lines (448-Ames 21521, 463-P1391643 and 523-P1219619) were subjected to two different soil temperatures (28 and 38 °C). The gas exchange, chlorophyll fluorescence, root morphology and central metabolism of leaves and roots were studied at the grain-filling stage. High soil temperature (38 °C) significantly influenced the shoot transpiration, stomatal conductance, photosynthesis, root growth and metabolism of all lines. The root length and area were significantly reduced in lines 448 and 463 in response to the stress, while only a small non-specific reduction was observed in line 523 in response to the treatment. The shift of root metabolites in response to high soil temperature was also genotype specific. In response to high soil temperature, glutamate, proline and pyroglutamate were reduced in line 448, and alanine, aspartate, glycine, pyroglutamate, serine, threonine and valine were accumulated in line 463. In the roots of line 523, serine, threonine, valine, isomaltose, maltose, raffinose, malate and itaconate were accumulated. Root tolerance to high soil temperature was evident in line 523, in its roots growth potential, lower photosynthesis and stomatal conductance rates, and effective utilization and assimilation of membrane carbon and nitrogen, coupled with the accumulation of protective metabolites. Copyright © 2016. Published by Elsevier Masson SAS.

  11. Differential TOR activation and cell proliferation in Arabidopsis root and shoot apexes.

    Science.gov (United States)

    Li, Xiaojuan; Cai, Wenguo; Liu, Yanlin; Li, Hui; Fu, Liwen; Liu, Zengyu; Xu, Lin; Liu, Hongtao; Xu, Tongda; Xiong, Yan

    2017-03-07

    The developmental plasticity of plants relies on the remarkable ability of the meristems to integrate nutrient and energy availability with environmental signals. Meristems in root and shoot apexes share highly similar molecular players but are spatially separated by soil. Whether and how these two meristematic tissues have differential activation requirements for local nutrient, hormone, and environmental cues (e.g., light) remain enigmatic in photosynthetic plants. Here, we report that the activation of root and shoot apexes relies on distinct glucose and light signals. Glucose energy signaling is sufficient to activate target of rapamycin (TOR) kinase in root apexes. In contrast, both the glucose and light signals are required for TOR activation in shoot apexes. Strikingly, exogenously applied auxin is able to replace light to activate TOR in shoot apexes and promote true leaf development. A relatively low concentration of auxin in the shoot and high concentration of auxin in the root might be responsible for this distinctive light requirement in root and shoot apexes, because light is required to promote auxin biosynthesis in the shoot. Furthermore, we reveal that the small GTPase Rho-related protein 2 (ROP2) transduces light-auxin signal to activate TOR by direct interaction, which, in turn, promotes transcription factors E2Fa,b for activating cell cycle genes in shoot apexes. Consistently, constitutively activated ROP2 plants stimulate TOR in the shoot apex and cause true leaf development even without light. Together, our findings establish a pivotal hub role of TOR signaling in integrating different environmental signals to regulate distinct developmental transition and growth in the shoot and root.

  12. DDT uptake by arbuscular mycorrhizal alfalfa and depletion in soil as influenced by soil application of a non-ionic surfactant

    International Nuclear Information System (INIS)

    Wu Naiying; Zhang Shuzhen; Huang Honglin; Shan Xiaoquan; Christie, Peter; Wang Youshan

    2008-01-01

    A greenhouse pot experiment was conducted to investigate the colonization of alfalfa roots by the arbuscular mycorrhizal (AM) fungus Glomus etunicatum and application of the non-ionic surfactant Triton X-100 on DDT uptake by alfalfa and depletion in soil. Mycorrhizal colonization led to an increase in the accumulation of DDT in roots but a decrease in shoots. The combination of AM inoculation and Triton X-100 application enhanced DDT uptake by both the roots and shoots. Application of Triton X-100 gave much lower residual concentrations of DDT in the bulk soil than in the rhizosphere soil or in the bulk soil without Triton X-100. AM colonization significantly increased bacterial and fungal counts and dehydrogenase activity in the rhizosphere soil. The combined AM inoculation of plants and soil application of surfactant may have potential as a biotechnological approach for the decontamination of soil polluted with DDT. - Combined colonization of alfalfa roots by an arbuscular mycorrhizal fungus and addition of non-ionic surfactant to the soil promoted root and shoot uptake and soil dissipation of DDT

  13. DDT uptake by arbuscular mycorrhizal alfalfa and depletion in soil as influenced by soil application of a non-ionic surfactant

    Energy Technology Data Exchange (ETDEWEB)

    Wu Naiying [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing 100085 (China); Zhang Shuzhen [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing 100085 (China)], E-mail: szzhang@rcees.ac.cn; Huang Honglin; Shan Xiaoquan [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing 100085 (China); Christie, Peter [Agricultural and Environmental Science Department, Queen' s University Belfast, Newforge Lane, Belfast BT9 5PX (United Kingdom); Wang Youshan [Municipal Academy of Agriculture and Forestry, Institute of Plant Nutrition and Resources, Beijing 100097 (China)

    2008-02-15

    A greenhouse pot experiment was conducted to investigate the colonization of alfalfa roots by the arbuscular mycorrhizal (AM) fungus Glomus etunicatum and application of the non-ionic surfactant Triton X-100 on DDT uptake by alfalfa and depletion in soil. Mycorrhizal colonization led to an increase in the accumulation of DDT in roots but a decrease in shoots. The combination of AM inoculation and Triton X-100 application enhanced DDT uptake by both the roots and shoots. Application of Triton X-100 gave much lower residual concentrations of DDT in the bulk soil than in the rhizosphere soil or in the bulk soil without Triton X-100. AM colonization significantly increased bacterial and fungal counts and dehydrogenase activity in the rhizosphere soil. The combined AM inoculation of plants and soil application of surfactant may have potential as a biotechnological approach for the decontamination of soil polluted with DDT. - Combined colonization of alfalfa roots by an arbuscular mycorrhizal fungus and addition of non-ionic surfactant to the soil promoted root and shoot uptake and soil dissipation of DDT.

  14. Soil Compressibility Models for a Wide Stress Range

    KAUST Repository

    Chong, Song-Hun

    2016-03-03

    Soil compressibility models with physically correct asymptotic void ratios are required to analyze situations that involve a wide stress range. Previously suggested models and other functions are adapted to satisfy asymptotic void ratios at low and high stress levels; all updated models involve four parameters. Compiled consolidation data for remolded and natural clays are used to test the models and to develop correlations between model parameters and index properties. Models can adequately fit soil compression data for a wide range of stresses and soil types; in particular, models that involve the power of the stress σ\\'β display higher flexibility to capture the brittle response of some natural soils. The use of a single continuous function avoids numerical discontinuities or the need for ad hoc procedures to determine the yield stress. The tangent stiffness-readily computed for all models-should not be mistaken for the small-strain constant-fabric stiffness. © 2016 American Society of Civil Engineers.

  15. Sirococcus Shoot Blight

    Science.gov (United States)

    Thomas H. Nicholls; Kathryn Robbins

    1984-01-01

    Sirococcus shoot blight, caused by the fungus Sirococcus strobilinus Preuss, affects conifers in the Northern United States and southern Canada. The fungus infects the new shoots; diseased seedlings and saplings are especially affected. In the United States, sirococcus shoot blight has become increasingly widespread since the early 1970's. When favorable...

  16. PERBANDINGAN JUMP SHOOT DENGAN AWALAN DAN TANPA AWALAN TERHADAP PENINGKATAN KETEPATAN SHOOTING DALAM PERMAINAN BOLABASKET

    OpenAIRE

    I Gusti Ngurah Agung Cahya Prananta; N. Adiputra; I P G Adiatmika

    2015-01-01

    The effectiveness of  jump-shoot technique step jump shoot and still jump shoot in a game is still questionable,  because many different assumptions arise. One opinion stated that step jump shoot was more effective and the other stated that and still jump shoot was more efective. Therefore it is necessary to do research on the analysis of the results of step jump shoot and and still jump shoot to improve the accuracy of shooting in a basketball. The experimental research had been conducted on...

  17. Chlordecone Transfer and Distribution in Maize Shoots.

    Science.gov (United States)

    Pascal-Lorber, Sophie; Létondor, Clarisse; Liber, Yohan; Jamin, Emilien L; Laurent, François

    2016-01-20

    Chlordecone (CLD) is a persistent organic pollutant (POP) that was mainly used as an insecticide against banana weevils in the French West Indies (1972-1993). Transfer of CLD via the food chain is now the major mechanism for exposure of the population to CLD. The uptake and the transfer of CLD were investigated in shoots of maize, a C4 model plant growing under tropical climates, to estimate the exposure of livestock via feed. Maize plants were grown on soils contaminated with [(14)C]CLD under controlled conditions. The greatest part of the radioactivity was associated with roots, nearly 95%, but CLD was detected in whole shoots, concentrations in old leaves being higher than those in young ones. CLD was thus transferred from the base toward the plant top, forming an acropetal gradient of contaminant. In contrast, results evidenced the existence of a basipetal gradient of CLD concentration within leaves whose extremities accumulated larger amounts of CLD because of evapotranspiration localization. Extractable residues accounted for two-thirds of total residues both in roots and in shoots. This study highlighted the fact that the distribution of CLD contamination within grasses resulted from a conjunction between the age and evapotranspiration rate of tissues. CLD accumulation in fodder may be the main route of exposure for livestock.

  18. Modeling soil evaporation efficiency in a range of soil and atmospheric conditions using a meta-analysis approach

    OpenAIRE

    Merlin , O; Stefan , V ,; Amazirh , A; Chanzy , A; Ceschia , E; Er-Raki , S; Gentine , P; Tallec , T; Ezzahar , J; Bircher , S; Beringer , J; Khabba , S

    2016-01-01

    International audience; A meta-analysis data-driven approach is developed to represent the soil evaporative efficiency (SEE) defined as the ratio of actual to potential soil evaporation. The new model is tested across a bare soil database composed of more than 30 sites around the world, a clay fraction range of 0.02-0.56, a sand fraction range of 0.05-0.92, and about 30,000 acquisition times. SEE is modeled using a soil resistance ($r_{ss}$) formulation based on surface soil moisture ($\\theta...

  19. Branch architecture in Ginkgo biloba: wood anatomy and long shoot-short shoot interactions.

    Science.gov (United States)

    Little, Stefan A; Jacobs, Brooke; McKechnie, Steven J; Cooper, Ranessa L; Christianson, Michael L; Jernstedt, Judith A

    2013-10-01

    Ginkgo, centrally placed in seed plant phylogeny, is considered important in many phylogenetic and evolutionary studies. Shoot dimorphism of Ginkgo has been long noted, but no work has yet been done to evaluate the relationships between overall branch architecture and wood ring characters, shoot growth, and environmental conditions. • Branches, sampled from similar canopy heights, were mapped with the age of each long shoot segment determined by counting annual leaf-scar series on its short shoots. Transverse sections were made for each long shoot segment and an adjacent short shoot; wood ring thickness, number of rings, and number of tracheids/ring were determined. Using branch maps, we identified wood rings for each long shoot segment to year and developmental context of each year (distal short shoot growth only vs. at least one distal long shoot). Climate data were also analyzed in conjunction with developmental context. • Significantly thicker wood rings occur in years with distal long shoot development. The likelihood that a branch produced long shoots in a given year was lower with higher maximum annual temperature. Annual maximum temperature was negatively correlated with ring thickness in microsporangiate trees only. Annual minimum temperatures were correlated differently with ring thickness of megasporangiate and microsporangiate trees, depending on the developmental context. There were no significant effects associated with precipitation. • Overall, developmental context alone predicts wood ring thickness about as well as models that include temperature. This suggests that although climatic factors may be strongly correlated with wood ring data among many gymnosperm taxa, at least for Ginkgo, correlations with climate data are primarily due to changes in proportions of shoot developmental types (LS vs. SS) across branches.

  20. Influence of triethyl phosphate on phosphatase activity in shooting range soil: Isolation of a zinc-resistant bacterium with an acid phosphatase.

    Science.gov (United States)

    Story, Sandra; Brigmon, Robin L

    2017-03-01

    Phosphatase-mediated hydrolysis of organic phosphate may be a viable means of stabilizing heavy metals via precipitation as a metal phosphate in bioremediation applications. We investigated the effect of triethyl phosphate (TEP) on soil microbial-phosphatase activity in a heavy-metal contaminated soil. Gaseous TEP has been used at subsurface sites for bioremediation of organic contaminants but not applied in heavy-metal contaminated areas. Little is known about how TEP affects microbial activity in soils and it is postulated that TEP can serve as a phosphate source in nutrient-poor groundwater and soil/sediments. Over a 3-week period, TEP amendment to microcosms containing heavy-metal contaminated soil resulted in increased activity of soil acid-phosphatase and repression of alkaline phosphatase, indicating a stimulatory effect on the microbial population. A soil-free enrichment of microorganisms adapted to heavy-metal and acidic conditions was derived from the TEP-amended soil microcosms using TEP as the sole phosphate source and the selected microbial consortium maintained a high acid-phosphatase activity with repression of alkaline phosphatase. Addition of 5mM zinc to soil-free microcosms had little effect on acid phosphatase but inhibited alkaline phosphatase. One bacterial member from the consortium, identified as Burkholderia cepacia sp., expressed an acid-phosphatase activity uninhibited by high concentrations of zinc and produced a soluble, indigo pigment under phosphate limitation. The pigment was produced in a phosphate-free medium and was not produced in the presence of TEP or phosphate ion, indicative of purple acid-phosphatase types that are pressed by bioavailable phosphate. These results demonstrate that TEP amendment was bioavailable and increased overall phosphatase activity in both soil and soil-free microcosms supporting the possibility of positive outcomes in bioremediation applications. Copyright © 2016. Published by Elsevier Inc.

  1. Induction of shoot regeneration in cotyledon explants of the oilseed crop Sesamum indicum L.

    Directory of Open Access Journals (Sweden)

    Masochon Zimik

    2017-12-01

    Full Text Available Sesamum indicum is an ancient oilseed crop known for its high quality edible oil and its medicinally important lignans. The crop is said to be recalcitrant to plant tissue culture thus limiting the use of modern biotechnology for its genetic improvement. We present here a protocol describing plant regeneration through adventitious shoot formation from cotyledons dissected from sesame seeds soaked for four hours in water. Subculturing of the cotyledons after two weeks of culture on to a fresh Murashige and Skoog medium leads to differentiation of adventitious shoots from the proximal cut end of the explant. Culture of cotyledons on a medium containing 9% sucrose for a couple of weeks prior to transfer to MS medium supplemented with 3% sucrose induced a higher frequency of shoot regeneration. The highest frequency of 25% adventitious shoot regeneration was observed for S. indicum variety UMA. This variety also turned out to be the best among the ten genotypes tested for shoot regeneration through tissue culture. While addition of IAA marginally improved regeneration, silver nitrate was found essential for enhancing the frequency of shoot regeneration. The regenerated shoots formed roots on full strength MS medium supplemented with 1 mg/l IBA and the rooted plants were established in soil.

  2. The relative influence of electrokinetic remediation design on the removal of As, Cu, Pb and Sb from shooting range soils

    DEFF Research Database (Denmark)

    Pedersen, Kristine B.; Jensen, Pernille Erland; Ottosen, Lisbeth M.

    2018-01-01

    to simultaneously optimise the removal by applying a stirred set-up, placement of the anode directly in the soil suspension, sieving the soil (analysis is a valuable tool for evaluating remediation measures depending soil...... and analysis was applied for assessing the efficiency of electrodialytic remediation treatment and variable importance varied for each of the studied metals. In general, applying a stirred set-up improved the metal removal, acidification time and reduced the energy consumption. The placement of the anode...... directly in the soil did not significantly influence the removal of Al, Mg, Mn, As and Pb, while moderately influencing the removal of Cu. Multivariate analysis (projections onto latent structures) revealed similar variable importance and optimal settings for removal of Cu and Pb. It is hence possible...

  3. [Effects of loess soil stabilization on Lolium perenne L. growth and root activity].

    Science.gov (United States)

    Liu, Yue-mei; Zhang, Xing-chang; Wang, Dan-dan

    2011-10-01

    Taking the loess soils with bulk density 1.2 g cm(-3), 1.3 g cm(-3), and 1.4 g cm(-3) from Ansai, Shaanxi Province as test objects, a pot experiment was conducted to study the effects of different amendment amount of soil stabilizer (EN-1 stabilizer) on the growth and root activity of ryegrass (Lolium perenne L.). Within the range of the bulk densities, the leaf chlorophyll content, root activity, root/shoot ratio, root biomass, and plant biomass of L. perenne all decreased with increasing soil bulk density, and were higher under the amendment of EN-1 stabilizer, as compared with the control. With increasing amendment amount of EN-1 stabilizer, the leaf chlorophyll content, root activity, root/shoot ratio, root biomass, and plant biomass had a trend of increased first and decreased then. Soil bulk density and stabilizer amendment amount had significant interactive effect on the root biomass and plant biomass. Overall, the values of the test indices were the highest under 1.3 g cm(-3) soil bulk density and 0.15% EN-1 stabilizer amendment amount.

  4. Remediation of lead and cadmium-contaminated soils.

    Science.gov (United States)

    Salama, Ahmed K; Osman, Khaled A; Gouda, Neama Abdel-Razeek

    2016-01-01

    The research was designated to study the ability of plants to bio-accumulate, translocate and remove the heavy metals, lead and cadmium from contaminated soil. The herbal plant ryegrass, Lolium multiflorum was investigated as a bio-accumulator plant for these metals. The translocation of these heavy metals in the herbal plant was compared considering root to shoot transport and redistribution of metals in the root and shoot system. The trace metal contents from root and shoot parts were determined using atomic absorption spectrometer. The results showed that the percent of lead and cadmium transferred to ryegrass plant were averaged as 51.39, and 74.57%, respectively, while those remained in the soil were averaged as 48.61 and 25.43% following 60 days of treatment. The soil-plant transfer index in root and shoot system of ryegrass was found to be 0.32 and 0.20 for lead, and 0.50 and 0.25 for cadmium. These findings indicated that the herbal plant ryegrass, Lolium multiflorum is a good accumulator for cadmium than lead. The soil-plant transfer factor (the conc. of heavy metal in plant to the conc. in soil) indicated that the mechanism of soil remedy using the investigated plant is phytoextraction where the amounts of heavy metals transferred by plant roots into the above ground portions were higher than that remained in the soil. The method offers green technology solution for the contamination problem since it is effective technology with minimal impact on the environment and can be easily used for soil remedy.

  5. PERBANDINGAN JUMP SHOOT DENGAN AWALAN DAN TANPA AWALAN TERHADAP PENINGKATAN KETEPATAN SHOOTING DALAM PERMAINAN BOLABASKET

    Directory of Open Access Journals (Sweden)

    I Gusti Ngurah Agung Cahya Prananta

    2015-01-01

    Full Text Available The effectiveness of  jump-shoot technique step jump shoot and still jump shoot in a game is still questionable,  because many different assumptions arise. One opinion stated that step jump shoot was more effective and the other stated that and still jump shoot was more efective. Therefore it is necessary to do research on the analysis of the results of step jump shoot and and still jump shoot to improve the accuracy of shooting in a basketball. The experimental research had been conducted on 20samples of people whowere selected randomly from the men's basketball club of the Faculty of Physical Educationand Health of Teacher Training Institute PGRI Bali. Samples were divided into two groups each  consisting of 10 people. Group I was given training step  jump shoot four sets of 10 reps  and Group II training still jump shoot four sets of 10 reps. The data before and after treatment were tested by SPSS computer program. The data were normally distributed and homogeneous so further tested using pairedt-test to compare the average values?? before and after training between each group, while the independent t-test was used to determine differences in mean values?? between the two groups. Paired t-test resulted the obtained data were significantly increased in both treatment groups p=0,001 in Group I and p=0,000 in Group II (p <0.05. Results of independent t-test found that both groups before training did not differ significantly p=0,926 (p>0.05 and after training both groups equally improve the accuracy of shooting because p=0,133 (p>0.05. It was concluded that botht raining improved the shooting accuracy and there was no difference between the effect of step jumps hoot and still jump shoot toward the shooting accuracy. It was suggested to improve the shooting accuracy in basketball used step jump shoot training and still jump shoot training four sets of 10 reps with a training frequency of 4 times a week for 6 weeks

  6. Germination and initial growth of Campomanesia xanthocarpa O. Berg. (Myrtaceae, in petroleum-contaminated soil and bioremediated soil

    Directory of Open Access Journals (Sweden)

    AM. Gogosz

    Full Text Available In 2000 there was an oil spill at the Getúlio Vargas Refinery (REPAR in Paraná. Nearly five years after contamination and the use of bioremediation, a study was carried out to identify the effects of the contaminated soil and the bioremediated soil on the germination and initial growth of C. xanthocarpa. The experiment was established with soil from REPAR, with three treatment groups: contaminated soil (C, bioremediated soil (B and uncontaminated soil (U; with five repetitions of 50 seeds each. There was no significant difference in the percentage of germination and the speed of germination index. The production of total biomass (30 - 60 days and shoot biomass (60 days was greater in the bioremediated soil compared to the other treatments. The averages for the root biomass were lower in the contaminated soil than in the bioremediated soil. The shoot length and the total length of the seedling in the contaminated soil and uncontaminated soil were lower than in the bioremediated soil.

  7. Influence of diesel contamination in soil on growth and dry matter partitioning of Lactuca sativa and Ipomoea batatas.

    Science.gov (United States)

    Fatokun, Kayode; Zharare, Godfrey Elijah

    2015-09-01

    Phytotoxic effect of diesel contaminated soil was investigated on growth and dry matter partitioning in Lactuca sativa and Ipomoea batatas in greenhouse pot experiment at two concentration range (0-30 ml and 0-6 ml diesel kg(-1) soil) for 14 weeks. The results indicated thatwhole plant biomass, stem length, root length, number of leaves and leaf chlorophyll in two plants were negatively correlated with increasing diesel concentrations. The critical concentration of diesel associated with 10% decrease in plant growth was 0.33 ml for lettuce and 1.50 ml for sweet potato. Thus, growth of lettuce in diesel contaminated soil was more sensitive than sweet potato. The pattern of dry matter partitioning between root and shoot in both plants were similar. In 0-6 ml diesel contamination range, allocation of dry matter to shoot system was favoured resulting in high shoot: root ratio of 4.54 and 12.91 for lettuce and sweet potato respectively. However, in 0-30 ml diesel contamination range, allocation of dry matter to root was favoured, which may have been an adaptive mechanism in which the root system was used for storage in addition to increasing the capacity for foraging for mineral nutrients and water. Although lettuce accumulated more metals in its tissue than sweet potato, the tissue mineral nutrients in both species did not vary to great extent. The critical diesel concentration for toxicity suggested that the cause of mortality and poor growth of sweet potato and lettuce grown in diesel contaminated soil was due to presence of hydrocarbons in diesel.

  8. Lead phytotoxicity in soils and nutrient solutions is related to lead induced phosphorus deficiency

    International Nuclear Information System (INIS)

    Cheyns, Karlien; Peeters, Sofie; Delcourt, Dorien; Smolders, Erik

    2012-01-01

    This study was set up to relate lead (Pb) bioavailability with its toxicity to plants in soils. Tomato and barley seedlings were grown in six different PbCl 2 spiked soils (pH: 4.7–7.4; eCEC: 4.2–41.7 cmol c /kg). Soils were leached and pH corrected after spiking to exclude confounding factors. Plant growth was halved at 1600–6500 mg Pb/kg soil for tomato and at 1900–8300 mg Pb/kg soil for barley. These soil Pb threshold were unrelated to soil pH, organic carbon, texture or eCEC and neither soil solution Pb nor Pb 2+ ion activity adequately explained Pb toxicity among soils. Shoot phosphorus (P) concentrations significantly decreased with increasing soil Pb concentrations. Tomato grown in hydroponics at either varying P supply or at increasing Pb (equal initial P) illustrated that shoot P explained growth response in both scenarios. The results suggest that Pb toxicity is partially related to Pb induced P deficiency, likely due to lead phosphate precipitation. - Highlights: ► Tomato and barley shoot growth was affected by Pb toxicity in six different soils. ► Soil properties did not explain differences in plant Pb toxicity among soils. ► Neither soil solution Pb nor Pb 2+ ion activity explained Pb toxicity among soils. ► Shoot phosphorus concentration decreased with increasing soil Pb concentrations. ► Lead induced a P deficiency in plants, likely due to lead phosphate precipitation. - Soil properties did not explain differences in plant lead toxicity among different soils. Shoot phosphorus concentration decreased with increasing soil lead concentrations.

  9. Diversity of soil fungi in North 24 Parganas and their antagonistic potential against Leucinodes orbonalis Guen. (Shoot and fruit borer of brinjal).

    Science.gov (United States)

    Pal, Sujoy; Ghosh, Swapan Kumar

    2014-12-01

    Soil samples were collected from agricultural fields and gardens in North 24 Parganas, West Bengal, and fungi species were isolated from them. Thirty-one fungal species were isolated with 19 found in agricultural soil and 28 in garden soil. Twenty-eight out of 31 were identified using cultural and microscopic characters, and three were unidentified. The diversity of isolated fungi was calculated by Simpson's diversity index. The garden soil possessed more fungal colonies (750) than agricultural soil (477). In agricultural soil, the dominant fungi were Aspergillus niger, Rhizopus oryzae, and Penicillium expansum, and the dominant fungi of garden soil were A. niger and Fusarium moniliforme. Simpson's diversity index indicated that garden soil had more fungal diversity (0.939) than agricultural soil (0.896). The entomopathogenic capacity of the isolated fungi was tested against the brinjal shoot and fruit borer (Leucinodes orbonalis Guen) which is the major insect pest of brinjal. The isolated fungi were screened against larva of L. orbonalis for their entomopathogenic potential. Beauveria bassiana, A. niger, and P. expansum showed appreciable antagonism to L. orbonalis, and their lethal doses with 50 % mortality (LD50s) were 4.0 × 10(7), 9.06 × 10(7), and 1.50 × 10(8) spore/mL, respectively, and their times taken to reach 50 % mortality (LT50s) were 9.77, 10.56, and 10.60 days, respectively. This work suggests the restriction of chemical pesticide application in agricultural fields to increase fungal diversity. The entomopathogenic efficacy of B. bassiana could be used in agricultural fields to increase fugal diversity and protect the brinjal crop.

  10. The Level of Vision Necessary for Competitive Performance in Rifle Shooting: Setting the Standards for Paralympic Shooting with Vision Impairment.

    Science.gov (United States)

    Allen, Peter M; Latham, Keziah; Mann, David L; Ravensbergen, Rianne H J C; Myint, Joy

    2016-01-01

    The aim of this study was to investigate the level of vision impairment (VI) that would reduce performance in shooting; to guide development of entry criteria to visually impaired (VI) shooting. Nineteen international-level shooters without VI took part in the study. Participants shot an air rifle, while standing, toward a regulation target placed at the end of a 10 m shooting range. Cambridge simulation glasses were used to simulate six different levels of VI. Visual acuity (VA) and contrast sensitivity (CS) were assessed along with shooting performance in each of seven conditions of simulated impairment and compared to that with habitual vision. Shooting performance was evaluated by calculating each individual's average score in every level of simulated VI and normalizing this score by expressing it as a percentage of the baseline performance achieved with habitual vision. Receiver Operating Characteristic curves were constructed to evaluate the ability of different VA and CS cut-off criteria to appropriately classify these athletes as achieving 'expected' or 'below expected' shooting results based on their performance with different levels of VA and CS. Shooting performance remained relatively unaffected by mild decreases in VA and CS, but quickly deteriorated with more moderate losses. The ability of visual function measurements to classify shooting performance was good, with 78% of performances appropriately classified using a cut-off of 0.53 logMAR and 74% appropriately classified using a cut-off of 0.83 logCS. The current inclusion criteria for VI shooting (1.0 logMAR) is conservative, maximizing the chance of including only those with an impairment that does impact performance, but potentially excluding some who do have a genuine impairment in the sport. A lower level of impairment would include more athletes who do have a genuine impairment but would potentially include those who do not actually have an impairment that impacts performance in the sport. An

  11. Relationships between soil properties and toxicity of copper and nickel to bok choy and tomato in Chinese soils.

    Science.gov (United States)

    Li, Bo; Zhang, Hongtao; Ma, Yibing; McLaughlin, Mike J

    2013-10-01

    The toxicity of copper (Cu) and nickel (Ni) to bok choy and tomato shoot growth was investigated in a wide range of Chinese soils with and without leaching with artificial rainwater. The results showed that the variations of Ni toxicity induced by soil properties were wider than those of Cu toxicity to both tomato and bok choy plant growth. Leaching generally decreased the toxicity of Cu and Ni added to soils, which also depended on soils, metals, and test plant species. Soil factors controlling metal phytotoxicity were found to be soil pH and soil organic carbon content for Cu, and soil pH for Ni. It was also found that soil pH had stronger effects on Ni toxicity than on Cu toxicity. Predictive toxicity models based on these soil factors were developed. These toxicity models for Cu and Ni toxicity to tomato plant growth were validated using an independent data set for European soils. These models could be applied to predict the Cu and Ni phytotoxicity in not only Chinese soils but also European soils. © 2013 SETAC.

  12. Phytoextraction and estimating optimal time for remediation of Cd-contaminated soils by Spinach

    Directory of Open Access Journals (Sweden)

    Somayyeh Eisazadeh Lazarjan

    2016-05-01

    Full Text Available The so-called phytoextraction in which hyperaccumulator plants are used to remediate the contaminated soils is proven to be an efficient method. The objective of this study was to investigate the capability of Spinach for phytoremediation of cadmium from Cd-contaminated soils and determine the efficiency extent of spinach for phytoremediation. For this purpose, a randomized block experimental design whit five treatments including 0, 15, 30, 60 and 120 mg Cd/ kg soil and three replications was established in the greenhouse. After contamination the soils with different levels of cadmium, spinach seeds were planted. When plants were fully developed, plants were harvested and their cadmium contents in shoot and roots as well as the soil-cadmium were measured. The results indicated that by increasing Cd concentration in soil, the major Cd accumulation was occurred in the roots rather than shoots. Maximum cadmium concentration within the shoots and roots was 73.7 and 75.86 mg/kg soil, respectively. According to Spinach ability to absorb high concentration of cadmium in the root zone and its high biomass and capability of Cadmium accumulation in shoots, Spinach can be used as hyperaccumulator plant to remediate cadmium from Cd-contaminated soils. But, according to minimum remediation time and maximum dry matter for the 30 mg Cd/ kg soil, maximum Cd extracted by shoots in hectare/year was in 30 mg Cd/ kg soil. It can be concluded that Spinach is a suitable plant for phytoremediation of slightly and to moderately cadmium contaminated soils.

  13. Photosynthesis of a scots pine shoot: the effect of shoot inclination on the photosynthetic response of a shoot subjected to direct radiation

    International Nuclear Information System (INIS)

    Oker-Blom, P.; Kellomaki, S.; Smolander, H.

    1983-01-01

    A set of photosynthetic responses of a Scots pine (Pinus sylvestris L.) shoot to light was derived from the shoot geometry and the photosynthetic response of a single needle. Computations showed that the shape of the photosynthesis light-curves varies substantially depending on the direction of radiation relative to the shoot position. Differences in the initial and maximum rates of photosynthesis were due to changes in the effective projection area and the irradiated fraction of the shoot, respectively

  14. Phytoextraction of lead from firing range soils with Vetiver grass

    Science.gov (United States)

    E. W. Wilde; R. L. Brigmon; D. L. Dunn; M. A. Heitkamp; D. C. Dagnan

    2007-01-01

    Vetiver grass (Vetiveria zizanoides) along with soil amendments were evaluated for phytoextraction of lead and other metals (zinc, copper, and iron) from the soil of an active firing range at the Savannah River Site, SC. Lead-contaminated soil (300-4,500 ppm/kg) was collected, dried, placed in pots, fertilized, and used as a medium for growing...

  15. School Shootings and Student Performance

    OpenAIRE

    Panu Poutvaara; Olli Ropponen

    2010-01-01

    In this paper, we study how high school students reacted to the shocking news of a school shooting. The shooting coincided with national high-school matriculation exams. As there were exams both before and after the shooting, we can use a difference-in-differences analysis to uncover how the school shooting affected the test scores compared to previous years. We find that the average performance of young men declined due to the school shooting, whereas we do not observe a similar pattern for ...

  16. Shoot regeneration from cotyledonary leaf explants of jatropha curcas: A biodiesel plant

    KAUST Repository

    Kumar, Nitish Chandramohana

    2010-03-07

    A simple, high frequency, and reproducible method for plant regeneration through direct organogenesis from cotyledonary leaf explants of Jatropha curcas was developed using Murashige and Skoog (MS) medium supplemented with different concentrations of thidiazuron (TDZ) or 6-benzyl aminopurine (BAP). Medium containing TDZ has greater influence on regeneration as compared to BAP. The induced shoot buds were transferred to MS medium containing 10 lM kinetin (Kn), 4.5 lM BAP, and 5.5 lM a-naphthaleneacetic acid (NAA) for shoot proliferation. The proliferated shoots could be elongated on MS medium supplemented with different concentrations and combinations of BAP, indole-3-acetic acid (IAA), NAA, and indole-3-butyric acid (IBA). MS medium with 2.25 lM BAP and 8.5 lM IAA was found to be the best combination for shoot elongation. However, significant differences in plant regeneration and shoot elongation were observed among the genotypes studied. Rooting was achieved when the basal cut end of elongated shoots were dipped in half strength MS liquid medium containing dif- ferent concentrations and combinations of IBA, IAA, and NAA for 4 days, followed by transfer to growth regulators free half strength MS medium supplemented 0.25 mg l-1 activated charcoal. Elongated shoot treated with 15 lM IBA, 5.7 lM IAA, and 11 lM NAA resulted in highest percent rooting. The rooted plants could be established in soil with more than 90% survival rate. The method developed may be useful in improvement of J. curcas through genetic modification. © Franciszek Górski Institute of Plant Physiology, Polish Academy of Sciences, Kraków 2010.

  17. Shoot regeneration from cotyledonary leaf explants of jatropha curcas: A biodiesel plant

    KAUST Repository

    Kumar, Nitish Chandramohana; Vijay Anand, K. G.; Reddy, Muppala P.

    2010-01-01

    A simple, high frequency, and reproducible method for plant regeneration through direct organogenesis from cotyledonary leaf explants of Jatropha curcas was developed using Murashige and Skoog (MS) medium supplemented with different concentrations of thidiazuron (TDZ) or 6-benzyl aminopurine (BAP). Medium containing TDZ has greater influence on regeneration as compared to BAP. The induced shoot buds were transferred to MS medium containing 10 lM kinetin (Kn), 4.5 lM BAP, and 5.5 lM a-naphthaleneacetic acid (NAA) for shoot proliferation. The proliferated shoots could be elongated on MS medium supplemented with different concentrations and combinations of BAP, indole-3-acetic acid (IAA), NAA, and indole-3-butyric acid (IBA). MS medium with 2.25 lM BAP and 8.5 lM IAA was found to be the best combination for shoot elongation. However, significant differences in plant regeneration and shoot elongation were observed among the genotypes studied. Rooting was achieved when the basal cut end of elongated shoots were dipped in half strength MS liquid medium containing dif- ferent concentrations and combinations of IBA, IAA, and NAA for 4 days, followed by transfer to growth regulators free half strength MS medium supplemented 0.25 mg l-1 activated charcoal. Elongated shoot treated with 15 lM IBA, 5.7 lM IAA, and 11 lM NAA resulted in highest percent rooting. The rooted plants could be established in soil with more than 90% survival rate. The method developed may be useful in improvement of J. curcas through genetic modification. © Franciszek Górski Institute of Plant Physiology, Polish Academy of Sciences, Kraków 2010.

  18. Anomalous needle numbers on dwarf shoots of Pinus mugo and P. uncinata (Pinaceae

    Directory of Open Access Journals (Sweden)

    Krystyna Boratyńska

    2011-01-01

    Full Text Available The frequency of occurrence of abnormal, three- (or more needle dwarf shoots of most southern and central European two-needle pine (Pinus species were studied. No specimens with more than two-needle dwarf shoots were found in a population of P. nigra Arnold subsp. salzmannii (Dunal Franco from the Iberian Peninsula and in two populations of P. uliginosa Neumann from the Sudeten Mountains in Central Europe. Single specimens were found within one population of P. pinaster Aiton from the Iberian Peninsula and among six populations of P. sylvestris L. from the Iberian Peninsula and Central Europe. Abnormal dwarf shoots mostly with three, but also four, five or six needles were found among 24 of 25 surveyed populations of P. mugo Turra and P. uncinata Ramond. The average frequency of specimens with at least one three-needle dwarf shoot was 24% for P. mugo and 20% for P. uncinata. The frequencies of occurrence varied significantly among studied populations and were highest in samples collected from the upper elevational range limits of the species in the mountains and near the northern limits of their ranges. The frequency of abnormal dwarf shoots in the same populations was significantly high in 2-3 consecutive years. Needles from three-needle dwarf shoots were not significantly shorter than those of two-needle shoots.

  19. Estimates of matter yield and N-uptake in sorghum grown on saline and non-saline soils manured with dhaincha (sesbania aculeata) plant residues utilizing 15N tracer techniques

    International Nuclear Information System (INIS)

    Kurdali, F.

    2002-11-01

    Pot experiments were conducted to study the effect of manuring with three types of plant residues (roots, shoots or roots plus shoots) of Dhaincha (Sesbania aculeata Pers.) on the yield and N-uptake of Sorghum bicolor grown in saline and non-saline soils. For measuring various sources of N-uptake, two isotopic dilution techniques were utilized by adding to these soils either 15 N-labelled inorganic N-fertilizer (indirect method) or 15 N-labelled sesbania leaves (direct method). For the indirect method, both soils manured with each type of sesbania residue, received four split applications of 15 N-labelled ammonium sulphate. Results indicated that each type of sesbania residue, applied as a green manure, resulted in significant increases in both dry matter yield and N-uptake of sorghum as compared with the un manured control. Moreover, sesbania residues decreased the harmful effect of salinity on plant growth. Percentages of N derived from residues (%Ndfr) in sorghum grown in non saline soil ranged between 3.9 and 33%; whereas, in saline soil, the observed values ranged between 4.9 and 19.8%. N recoveries in sorghum grown in non saline soil were 61, 45 and 37% of the total amount contained in the sesbania root, shoot and root plus shoot; whereas, values in sorghum grown in saline soils were 48, 14,8 and 15.7%, respectively. The beneficial effects of sesbania residues have been attributed not only to the additional N availability to the plants, but also to its effects on the enhancement of soil N uptake. Percentages and amounts of Ndfr calculated using the indirect method were not significantly different from those obtained by the direct method indicating that the indirect method used herein is feasible and simple for measuring N release from organic residues. It is suggested that the use of Sesbania aculeata residues, particularly the shoots, as a green manure, can provide a substantial portion of total N in sorghum. Moreover, the use of sesbania green manure in

  20. The Level of Vision Necessary for Competitive Performance in Rifle Shooting: Setting the Standards for Paralympic Shooting With Vision Impairment

    Directory of Open Access Journals (Sweden)

    Peter M Allen

    2016-11-01

    Full Text Available The aim of this study was to investigate the level of vision impairment that would reduce performance in shooting; to guide development of entry criteria to visually impaired (VI shooting. Nineteen international-level shooters without vision impairment took part in the study. Participants shot an air rifle, while standing, towards a regulation target placed at the end of a 10m shooting range. Cambridge simulation glasses were used to simulate six different levels of vision impairment. Visual acuity (VA and contrast sensitivity (CS were assessed along with shooting performance in each of seven conditions of simulated impairment and compared to that with habitual vision. Shooting performance was evaluated by calculating each individual’s average score in every level of simulated vision impairment and normalising this score by expressing it as a percentage of the baseline performance achieved with habitual vision. Receiver Operating Characteristic (ROC curves were constructed to evaluate the ability of different VA and CS cut-off criteria to appropriately classify these athletes as achieving ‘expected’ or ‘below expected’ shooting results based on their performance with different levels of VA and CS. Shooting performance remained relatively unaffected by mild decreases in VA and CS, but quickly deteriorated with more moderate losses. The ability of visual function measurements to classify shooting performance was good, with 78% of performances appropriately classified using a cut-off of 0.53 logMAR and 74% appropriately classified using a cut-off of 0.83 logCS. The current inclusion criteria for VI shooting (1.0 logMAR is conservative, maximising the chance of including only those with an impairment that does impact performance, but potentially excluding some who do have a genuine impairment in the sport. A lower level of impairment would include more athletes who do have a genuine impairment but would potentially include those who do not

  1. Soil-borne microorganisms and soil-type affect pyrrolizidine alkaloids in Jacobaea vulgaris

    NARCIS (Netherlands)

    Joosten, L.; Mulder, P.P.J.; Klinkhamer, P.G.L.; Van Veen, J.A.

    2009-01-01

    Secondary metabolites like pyrrolizidine alkaloids (PAs) play a crucial part in plant defense. We studied the effects of soil-borne microorganisms and soil-type on pyrrolizidine alkaloids in roots and shoots of Jacobaea vulgaris. We used clones of two genotypes from a dune area (Meijendel),

  2. Pore-water chemistry explains zinc phytotoxicity in soil.

    Science.gov (United States)

    Kader, Mohammed; Lamb, Dane T; Correll, Ray; Megharaj, Mallavarapu; Naidu, Ravi

    2015-12-01

    Zinc (Zn) is a widespread soil contaminant arising from a numerous anthropogenic sources. However, adequately predicting toxicity of Zn to ecological receptors remains difficult due to the complexity of soil characteristics. In this study, we examined solid-solution partitioning using pore-water data and toxicity of Zn to cucumber (Cucumis sativus L.) in spiked soils. Pore-water effective concentration (ECx, x=10%, 20% and 50% reduction) values were negatively related to pH, indicating lower Zn pore water concentration were needed to cause phytotoxicity at high pH soils. Total dissolved zinc (Znpw) and free zinc (Zn(2+)) in soil-pore water successfully described 78% and 80.3% of the variation in relative growth (%) in the full dataset. When the complete data set was used (10 soils), the estimated EC50pw was 450 and 79.2 µM for Znpw and Zn(2+), respectively. Total added Zn, soil pore water pH (pHpw) and dissolve organic carbon (DOC) were the best predictors of Znpw and Zn(2+) in pore-water. The EC10 (total loading) values ranged from 179 to 5214 mg/kg, depending on soil type. Only pH measurements in soil were related to ECx total Zn data. The strongest relationship to ECx overall was pHca, although pHw and pHpw were in general related to Zn ECx. Similarly, when a solution-only model was used to predict Zn in shoot, DOC was negatively related to Zn in shoot, indicating a reduction in uptake/ translocation of Zn from solution with increasing DOC. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Multiple vantage points on the mental health effects of mass shootings.

    Science.gov (United States)

    Shultz, James M; Thoresen, Siri; Flynn, Brian W; Muschert, Glenn W; Shaw, Jon A; Espinel, Zelde; Walter, Frank G; Gaither, Joshua B; Garcia-Barcena, Yanira; O'Keefe, Kaitlin; Cohen, Alyssa M

    2014-09-01

    The phenomenon of mass shootings has emerged over the past 50 years. A high proportion of rampage shootings have occurred in the United States, and secondarily, in European nations with otherwise low firearm homicide rates; yet, paradoxically, shooting massacres are not prominent in the Latin American nations with the highest firearm homicide rates in the world. A review of the scientific literature from 2010 to early 2014 reveals that, at the individual level, mental health effects include psychological distress and clinically significant elevations in posttraumatic stress, depression, and anxiety symptoms in relation to the degree of physical exposure and social proximity to the shooting incident. Psychological repercussions extend to the surrounding affected community. In the aftermath of the deadliest mass shooting on record, Norway has been in the vanguard of intervention research focusing on rapid delivery of psychological support and services to survivors of the "Oslo Terror." Grounded on a detailed review of the clinical literature on the mental health effects of mass shootings, this paper also incorporates wide-ranging co-author expertise to delineate: 1) the patterning of mass shootings within the international context of firearm homicides, 2) the effects of shooting rampages on children and adolescents, 3) the psychological effects for wounded victims and the emergency healthcare personnel who care for them, 4) the disaster behavioral health considerations for preparedness and response, and 5) the media "framing" of mass shooting incidents in relation to the portrayal of mental health themes.

  4. Can we predict uranium bioavailability based on soil parameters? Part 2: soil solution uranium concentration is not a good bioavailability index.

    Science.gov (United States)

    Vandenhove, H; Van Hees, M; Wannijn, J; Wouters, K; Wang, L

    2007-01-01

    The present study aimed to quantify the influence of soil parameters on uranium uptake by ryegrass. Ryegrass was established on eighteen distinct soils, spiked with (238)U. Uranium soil-to-plant transfer factors (TF) ranged from 0.0003 to 0.0340kgkg(-1). There was no significant relation between the U soil-to-plant transfer (or total U uptake or flux) and the uranium concentration in the soil solution or any other soil factor measured, nor with the U recovered following selective soil extractions. Multiple linear regression analysis resulted in a significant though complex model explaining up to 99% of variation in TF. The influence of uranium speciation on uranium uptake observed was featured: UO(2)(+2), uranyl carbonate complexes and UO(2)PO(4)(-) seem the U species being preferentially taken up by the roots and transferred to the shoots. Improved correlations were obtained when relating the uranium TF with the summed soil solution concentrations of mentioned uranium species.

  5. Evaluation of Soil Loss and Erosion Control Measures on Ranges and Range Structures at Installations in Temperate Climates

    Science.gov (United States)

    2006-06-01

    Soil Loss Equation ( USLE ) and the Revised Universal Soil Loss Equation (RUSLE) continue to be widely accepted methods for estimating sediment loss...range areas. Therefore, a generalized design methodology using the Universal Soil Loss Equation ( USLE ) is presented to accommodate the variations...constructed use the slope most suitable to the area topography (3:1 or 4:1). Step 4: Using the Universal Soil Loss equation, USLE , find the values of A

  6. The propagation of a soil H218O labeling through the atmosphere-plant-soil system under drought using H218O and C18OO as two independent proxies

    Science.gov (United States)

    Barthel, Matthias; Sturm, Patrick; Hammerle, Albin; Siegwolf, Rolf; Gentsch, Lydia; Buchmann, Nina; Knohl, Alexander

    2013-04-01

    Above- and belowground processes in plants are tightly coupled via carbon and water flows through the atmosphere-plant-soil system. While recent studies elucidated the influence of drought on the carbon flow through plant and soil using 13C, much less is known about the propagation of 18O. Therefore, this study aimed to examine the timing and intensity of 18O enrichment in soil and shoot CO2 and H2O vapor fluxes of European beech saplings (Fagus sylvatica L.) after applying 18O-labeled water to the soil. A custom-made chamber system, separating shoot from soil compartments, allowed independent measurements of shoot and soil related processes in a controlled climate chamber environment. Gas-exchange of oxygen stable isotopes in CO2 and H2O-vapor served as the main tool for investigation and was monitored in real-time using laser spectroscopy. This is the first study measuring concurrently and continuously the enrichment of 18O in CO2 and H2O in shoot- and soil gas-exchange after applying 18O-labeled water to the soil. Photosynthesis (A) and stomatal conductance (gs) of drought-stressed plants showed an immediate coinciding small increase to the H218O irrigation event after only ~30 min. This rapid information transfer, however, was not accompanied by the arrival of 18O labeled water molecules within the shoot. The actual label induced 18O enrichment in transpired water and CO2 occurred not until ~4h after labeling. Further, the timing of the enrichment of 18O in the transpirational flux was similar in both treatments, thus pointing to similar transport rates. However, drought reduced the 18O exchange rate between H2O and CO2at the shoot level, likely caused by a smaller leaf CO2retroflux. Moreover, 18O exchange between H2O and CO2 occurred also in the soil. However, the there was no difference observed between the treatments.

  7. Soil ecotoxicity assessment using cadmium sensitive plants

    Energy Technology Data Exchange (ETDEWEB)

    An, Youn-Joo

    2004-01-01

    The crop plants, sorghum and cucumber, can be used as indicator species to assess ecotoxicity of soils contaminated by cadmium. - Four crop plant species (sweet corn, Zea may; wheat, Triticum aestivum; cucumber, Cucumis sativus; and sorghum, Sorghum bicolor) were tested to assess an ecotoxicity in cadmium-amended soils. The measurement endpoints used were seed germination and seedling growth (shoot and root). The presence of cadmium decreased the seedling growth. The medium effective concentration values (EC50) for shoot or root growth were calculated by the Trimmed Spearman-Karber method. Due to the greater accumulation of Cd to the roots, root growth was a more sensitive endpoint than shoot growth. Bioavailability and transport of Cd within plant were related to concentration and species. The ratio of bioaccumulation factor (BAF) in the shoots to the roots indicated high immobilization of Cd in the roots. Seed germination was insensitive to Cd toxicity, and is not recommended for a suitable assay. Among the test plants and test endpoints, root growth of sorghum and cucumber appears to be a good protocol to assess ecotoxicity of soils contaminated by Cd.

  8. Soil ecotoxicity assessment using cadmium sensitive plants

    International Nuclear Information System (INIS)

    An, Youn-Joo

    2004-01-01

    The crop plants, sorghum and cucumber, can be used as indicator species to assess ecotoxicity of soils contaminated by cadmium. - Four crop plant species (sweet corn, Zea may; wheat, Triticum aestivum; cucumber, Cucumis sativus; and sorghum, Sorghum bicolor) were tested to assess an ecotoxicity in cadmium-amended soils. The measurement endpoints used were seed germination and seedling growth (shoot and root). The presence of cadmium decreased the seedling growth. The medium effective concentration values (EC50) for shoot or root growth were calculated by the Trimmed Spearman-Karber method. Due to the greater accumulation of Cd to the roots, root growth was a more sensitive endpoint than shoot growth. Bioavailability and transport of Cd within plant were related to concentration and species. The ratio of bioaccumulation factor (BAF) in the shoots to the roots indicated high immobilization of Cd in the roots. Seed germination was insensitive to Cd toxicity, and is not recommended for a suitable assay. Among the test plants and test endpoints, root growth of sorghum and cucumber appears to be a good protocol to assess ecotoxicity of soils contaminated by Cd

  9. Soil Compressibility Models for a Wide Stress Range

    KAUST Repository

    Chong, Song-Hun; Santamarina, Carlos

    2016-01-01

    Soil compressibility models with physically correct asymptotic void ratios are required to analyze situations that involve a wide stress range. Previously suggested models and other functions are adapted to satisfy asymptotic void ratios at low

  10. Range expansion potential of two co-occurring invasive vines to marginal habitats in Turkey

    Science.gov (United States)

    Farooq, Shahid; Tad, Sonnur; Onen, Huseyin; Gunal, Hikmet; Caldiran, Ugur; Ozaslan, Cumali

    2017-10-01

    Niche distribution models accurately predict the potential distribution range of invasive plants into new habitats based on their climatic requirements in the native regions. However, these models usually ignore the marginal habitats which can limit the distribution of exotic plants. We therefore tested the seedling survival, growth and nutrient acquisition capabilities of two co-occurring invasive vines [Persicaria perfoliata (L.) H. Gross and Sicyos angulatus L.] in three different manipulative greenhouse experiments to infer their range expansion potential to marginal habitats in Turkey. First experiment included five different moisture availability regimes (100, 75, 50, 25 and 12.5% available water), second experiment consisted of four different salinity levels (0, 3, 6 and 12 dSm-1 soil salinity) and third experiment had four different soil textures (clay-1, clay-2, sandy loam and silt-clay-loam). Seedling mortality was only observed under extreme moisture deficiency in both plant species, while most of the transplanted seedlings of both species did not survive under 6 and 12 dSm-1 salinity levels. Soil textures had no effect on seedling survival. POLPE better tolerated low moisture availability and high salinity compared to SIYAN. Biomass production in both plant species was linearly reduced with increasing salinity and moisture deficiency. SIYAN invested more resources towards shoot, accumulated higher K and P, whereas POLPE maintained higher root-to-shoot ratio under all experimental conditions. Both plant species employed different strategies to cope with adverse environmental conditions, but failed to persist under high soil salinity and moisture deficiency. Our study suggest that both plant species have limited potential of range expansion to marginal habitats and will be limited to moist and humid areas only. Therefore, further research activities should be concentrated in these regions to develop effective management strategies against both species.

  11. [Effects of soil pH on the competitive uptake of amino acids by maize and microorganisms].

    Science.gov (United States)

    Ma, Qing Xu; Wang, Jun; Cao, Xiao Chuang; Sun, Yan; Sun, Tao; Wu, Liang Huan

    2017-07-18

    Organic nitrogen can play an important role in plant growth, and soil pH changed greatly due to the over-use of chemical fertilizers, but the effects of soil pH on the competitive uptake of amino acids by plants and rhizosphere microorganisms are lack of detailed research. To study the effects of soil pH on the uptake of amino acids by maize and soil microorganisms, two soils from Hangzhou and Tieling were selected, and the soil pH was changed by the electrokinesis, then the 15 N-labeled glycine was injected to the centrifuge tube with a short-term uptake of 4 h. Soil pH had a significant effect on the shoot and root biomass, and the optimal pH for maize shoot growth was 6.48 for Hangzhou red soil, while it was 7.65 for Tieling brown soil. For Hangzhou soil, the 15 N abundance of maize shoots under pH=6.48 was significantly higher than under other treatments, and the uptake amount of 15 N-glycine was also much higher. However, the 15 N abundance of maize shoots and roots under pH=7.65 Tieling soil was significantly lower than it under pH=5.78, but the uptake amount of 15 N-glycine under pH=7.65 was much higher. The microbial biomass C was much higher in pH=6.48 Hangzhou soil, while it was much lower in pH=7.65 Tieling soil. According to the results of root uptake, root to shoot transportation, and the competition with microorganisms, we suggested that although facing the fierce competition with microorganisms, the maize grown in pH=6.48 Hangzhou soil increased the uptake of glycine by increasing its root uptake and root to shoot transportation. While in pH=7.65 Tieling soil, the activity of microorganisms was decreased, which decreased the competition with maize for glycine, and increased the uptake of glycine by maize.

  12. performance of sorghum grown on a salt affected soil manured with dhaincha plant residues using a 15N isotopic dilution technique

    International Nuclear Information System (INIS)

    Kurdali, F.; Al-Ain, F.; Razok, A.; Al-Shamma, M.

    2008-01-01

    A field experiment was conducted on a salt-affected soil to determine the effect of application of three types of Dhaincha (Sesbania aculeata pers.) residues (R, roots; L, shoots; L+R, shoots plus roots) of on the performance of sorghum (Sorghum bicolor L.) using the indirect 15 N isotopic dilution technique. Results indicated that Sesbania residues (L and L+R), used as green manures significantly increased grain yield, dry matter production, N uptake, and water use efficiency of sorghum. Percentages of N derived from residues (%Ndfr) in sorghum ranged from 6.4 to 28%. The N recoveries in sorghum were 52, 19. and 19.7% of the total amount contained in Sesbania roots, shoots and roots plus shoots, respectively. The beneficial effects of Sesbania residues are attributed not only to the additional N availability to the plants, but also to effects on the enhancement of soil N uptake, particularly in the L+R treatment. The findings suggest that the use of Sesbania aculeata residues, as a green manure, can provide a substantial portion of total N in sorghum. In addition, the use of Sesbania green manure in salt-affected soils, as a bio-reclaiming material, can be a promising approach for enhancing plant growth on a sustainable basis. (author)

  13. Successful range-expanding plants experience less above-ground and below-ground enemy impact.

    Science.gov (United States)

    Engelkes, Tim; Morriën, Elly; Verhoeven, Koen J F; Bezemer, T Martijn; Biere, Arjen; Harvey, Jeffrey A; McIntyre, Lauren M; Tamis, Wil L M; van der Putten, Wim H

    2008-12-18

    Many species are currently moving to higher latitudes and altitudes. However, little is known about the factors that influence the future performance of range-expanding species in their new habitats. Here we show that range-expanding plant species from a riverine area were better defended against shoot and root enemies than were related native plant species growing in the same area. We grew fifteen plant species with and without non-coevolved polyphagous locusts and cosmopolitan, polyphagous aphids. Contrary to our expectations, the locusts performed more poorly on the range-expanding plant species than on the congeneric native plant species, whereas the aphids showed no difference. The shoot herbivores reduced the biomass of the native plants more than they did that of the congeneric range expanders. Also, the range-expanding plants developed fewer pathogenic effects in their root-zone soil than did the related native species. Current predictions forecast biodiversity loss due to limitations in the ability of species to adjust to climate warming conditions in their range. Our results strongly suggest that the plants that shift ranges towards higher latitudes and altitudes may include potential invaders, as the successful range expanders may experience less control by above-ground or below-ground enemies than the natives.

  14. Source-pathway-receptor investigation of the fate of trace elements derived from shotgun pellets discharged in terrestrial ecosystems managed for game shooting

    International Nuclear Information System (INIS)

    Sneddon, Jennifer; Clemente, Rafael; Riby, Philip; Lepp, Nicholas W.

    2009-01-01

    Spent shotgun pellets may contaminate terrestrial ecosystems. We examined the fate of elements originating from shotgun pellets in pasture and woodland ecosystems. Two source-receptor pathways: i) soil-soil pore water-plant and ii) whole earthworm/worm gut contents - washed and unwashed small mammal hair were investigated. Concentrations of Pb and associated contaminants were higher in soils from shot areas than controls. Arsenic and lead concentrations were positively correlated in soils, soil pore water and associated biota. Element concentrations in biota were below statutory levels in all locations. Bioavailability of lead to small mammals, based on concentrations in washed body hair was low. Lead movement from soil water to higher trophic levels was minor compared to lead adsorbed onto body surfaces. Lead was concentrated in earthworm gut and some plants. Results indicate that managed game shooting presents minimal risk in terms of element transfer to soils and their associated biota. - Source-receptor pathway analysis of a managed game shooting site showed no environmental risk of trace element transfer.

  15. Source-pathway-receptor investigation of the fate of trace elements derived from shotgun pellets discharged in terrestrial ecosystems managed for game shooting

    Energy Technology Data Exchange (ETDEWEB)

    Sneddon, Jennifer [School of Natural Sciences and Psychology, Liverpool John Moores University, Byrom Street, Liverpool L3 3AF (United Kingdom); Clemente, Rafael, E-mail: rclemente@cebas.csic.e [School of Natural Sciences and Psychology, Liverpool John Moores University, Byrom Street, Liverpool L3 3AF (United Kingdom); Riby, Philip [School of Pharmacy and Chemistry, Liverpool John Moores University, Liverpool L3 3AF (United Kingdom); Lepp, Nicholas W., E-mail: n.w.lepp@ljmu.ac.u [School of Natural Sciences and Psychology, Liverpool John Moores University, Byrom Street, Liverpool L3 3AF (United Kingdom)

    2009-10-15

    Spent shotgun pellets may contaminate terrestrial ecosystems. We examined the fate of elements originating from shotgun pellets in pasture and woodland ecosystems. Two source-receptor pathways: i) soil-soil pore water-plant and ii) whole earthworm/worm gut contents - washed and unwashed small mammal hair were investigated. Concentrations of Pb and associated contaminants were higher in soils from shot areas than controls. Arsenic and lead concentrations were positively correlated in soils, soil pore water and associated biota. Element concentrations in biota were below statutory levels in all locations. Bioavailability of lead to small mammals, based on concentrations in washed body hair was low. Lead movement from soil water to higher trophic levels was minor compared to lead adsorbed onto body surfaces. Lead was concentrated in earthworm gut and some plants. Results indicate that managed game shooting presents minimal risk in terms of element transfer to soils and their associated biota. - Source-receptor pathway analysis of a managed game shooting site showed no environmental risk of trace element transfer.

  16. Screening for new accumulator plants in Andes Range mines

    Science.gov (United States)

    Bech, Jaume; Roca, Núria

    2016-04-01

    Toxic metal pollution of waters and soils is a major environmental problem, and most conventional remediation approaches do not provide acceptable solutions. The use of plants or plant products to restore or stabilize contaminated sites, collectively known as phytoremediation, takes advantage of the natural abilities of plants to take up, accumulate, store, or degrade organic and inorganic substances. Although not a new concept, phytoremediation is currently being re-examined as an environmentally friendly, cost-effective means of reducing metal contaminated soil. Plants growing on naturally metal-enriched soils are of particular interest in this regard, since they are genetically tolerant to high metal concentrations and have an excellent adaptation to this multi-stress environment. Processes include using plants that tolerate and accumulate metals at high levels (phytoextraction) and using plants that can grow under conditions that are toxic to other plants while preventing, for example, soil erosion (phytostabilization). Soil and plant samples were taken at polymetallic mines in Peru, Ecuador and Chile. It is suggested that Plantago orbignyana Steinheil is a Pb hyperaccumulator. Moreover, unusually elevated concentrations of Pb (over 1000 mg kg-1) and Translocation Factor (TF) greater than one were also detected in shoots of 6 different plants species (Ageratina sp., Achirodine alata, Cortaderia apalothica, Epilobium denticulatum, Taraxacum officinalis and Trifolium repens) of a Caroline mine in Perú. Among the grass species (Poaceae), the highest shoot As concentration were found in Paspalum sp. (>1000 μg g-1) and Eriochola ramose (460 μg g-1) from the Cu mine in Peru and in Holcus lanatus and Pennisetum clandestinum (>200 μg g-1) from the silver mine in Ecuador. The shoot accumulation of Zn was highest in Baccharis amdatensis (>1900 μg g-1) and in Rumex crispus (1300 μg g-1) from the Ag mine in Ecuador (Bech et al., 2002). Paspalum racemosum also

  17. Inhibition of tomato shoot growth by over-irrigation is linked to nitrogen deficiency and ethylene.

    Science.gov (United States)

    Fiebig, Antje; Dodd, Ian C

    2016-01-01

    Although physiological effects of acute flooding have been well studied, chronic effects of suboptimal soil aeration caused by over-irrigation of containerized plants have not, despite its likely commercial significance. By automatically scheduling irrigation according to soil moisture thresholds, effects of over-irrigation on soil properties (oxygen concentration, temperature and moisture), leaf growth, gas exchange, phytohormone [abscisic acid (ABA) and ethylene] relations and nutrient status of tomato (Solanum lycopersicum Mill. cv. Ailsa Craig) were studied. Over-irrigation slowly increased soil moisture and decreased soil oxygen concentration by 4%. Soil temperature was approximately 1°C lower in the over-irrigated substrate. Over-irrigating tomato plants for 2 weeks significantly reduced shoot height (by 25%) and fresh weight and total leaf area (by 60-70%) compared with well-drained plants. Over-irrigation did not alter stomatal conductance, leaf water potential or foliar ABA concentrations, suggesting that growth inhibition was not hydraulically regulated or dependent on stomatal closure or changes in ABA. However, over-irrigation significantly increased foliar ethylene emission. Ethylene seemed to inhibit growth, as the partially ethylene-insensitive genotype Never ripe (Nr) was much less sensitive to over-irrigation than the wild type. Over-irrigation induced significant foliar nitrogen deficiency and daily supplementation of small volumes of 10 mM Ca(NO3 )2 to over-irrigated soil restored foliar nitrogen concentrations, ethylene emission and shoot fresh weight of over-irrigated plants to control levels. Thus reduced nitrogen uptake plays an important role in inhibiting growth of over-irrigated plants, in part by stimulating foliar ethylene emission. © 2015 Scandinavian Plant Physiology Society.

  18. Chinese tallow trees (Triadica sebifera) from the invasive range outperform those from the native range with an active soil community or phosphorus fertilization.

    Science.gov (United States)

    Zhang, Ling; Zhang, Yaojun; Wang, Hong; Zou, Jianwen; Siemann, Evan

    2013-01-01

    Two mechanisms that have been proposed to explain success of invasive plants are unusual biotic interactions, such as enemy release or enhanced mutualisms, and increased resource availability. However, while these mechanisms are usually considered separately, both may be involved in successful invasions. Biotic interactions may be positive or negative and may interact with nutritional resources in determining invasion success. In addition, the effects of different nutrients on invasions may vary. Finally, genetic variation in traits between populations located in introduced versus native ranges may be important for biotic interactions and/or resource use. Here, we investigated the roles of soil biota, resource availability, and plant genetic variation using seedlings of Triadica sebifera in an experiment in the native range (China). We manipulated nitrogen (control or 4 g/m(2)), phosphorus (control or 0.5 g/m(2)), soil biota (untreated or sterilized field soil), and plant origin (4 populations from the invasive range, 4 populations from the native range) in a full factorial experiment. Phosphorus addition increased root, stem, and leaf masses. Leaf mass and height growth depended on population origin and soil sterilization. Invasive populations had higher leaf mass and growth rates than native populations did in fresh soil but they had lower, comparable leaf mass and growth rates in sterilized soil. Invasive populations had higher growth rates with phosphorus addition but native ones did not. Soil sterilization decreased specific leaf area in both native and exotic populations. Negative effects of soil sterilization suggest that soil pathogens may not be as important as soil mutualists for T. sebifera performance. Moreover, interactive effects of sterilization and origin suggest that invasive T. sebifera may have evolved more beneficial relationships with the soil biota. Overall, seedlings from the invasive range outperformed those from the native range, however

  19. EPICORMIC SHOOTS INDUCTION AND ROOTING CUTTINGS OF Calophyllum brasiliense

    Directory of Open Access Journals (Sweden)

    Dagma Kratz

    2016-12-01

    Full Text Available Calophyllum brasiliense is present in a wide natural distribution range in Brazil and its monopodial growth, with a rectilinear stem and a moderately dense timber has attracted the attention from the logging industry in recent decades. In the meantime, the lack of efficient rescue and vegetative propagation methods of adult plants has been a narrowing condition for the selection of superior genotypes in breeding programs of the species. Therefore, we evaluate epicormic shoots induction methods and the rooting cuttings of 14 year-old Calophyllum brasiliense trees. From this scope, three methods of epicormic shoots induction were evaluated: coppicing, girdling and partial girdling. We evaluate the number of produced sprouts and the percentage of sprouted trees at 06, 12 and 15 months’ after the experiment installation. Results have indicated the feasibility of Calophyllum brasiliense vegetative rescue by cuttings method using epicormic shoots induced by coppicing and girdling. In contrast, partial girdling was not effective in epicormic shoots emission. Concerning adventitious roots, the sprouting technique had no influence in the rooting of cuttings, showing variation among the different stock plants.

  20. A study on zinc distribution in calcareous soils for cowpea (Vigna Unguiculata L.) and barely ( Hordeum Vulgare L.)

    Science.gov (United States)

    Boroomand, Naser; Maleki, Mohammad Reza

    2010-05-01

    Compared to other cereals, such as wheat and barley cultivars which have low sensitivity to Zn deficiency, cowpea is sensitive to zinc (Zn) deficiency, however it extensively grows even in soils with deficient in Zn. A 8-week greenhouse experiment was conducted to study the response of cowpea and barely to Zn in calcareous soils with different DTPA- Zn. The soil samples were taken from soil surface up to 0.3 m in which their DTPA- Zn ranged from 0.5 to 3.5 mg kg-1. Shoot dry matter, concentration and uptake of Zn were found to be significantly correlated with soil DTPA- Zn in cowpea and barely. Critical deficiency level of Zn in cowpea was 1.3 mg kg-1 in soil and 28.5 mg kg-1 in shoot dry matter, however, to barely symptoms of Zn deficiency was not observed and concentration of Zn was higher than the critical level reported in literatures. Organic carbon (OC), calcium carbonate equivalent (CCE), pH and field capacity soil moisture content(FC) were significantly correlated with plant responses to Zn which were the most influenced characteristics to Zn uptake by plants.

  1. Violence and school shootings.

    Science.gov (United States)

    Flannery, Daniel J; Modzeleski, William; Kretschmar, Jeff M

    2013-01-01

    Multiple-homicide school shootings are rare events, but when they happen they significantly impact individuals, the school and the community. We focus on multiple-homicide incidents and identified mental health issues of shooters. To date, studies of school shootings have concluded that no reliable profile of a shooter exists, so risk should be assessed using comprehensive threat assessment protocols. Existing studies primarily utilize retrospective case histories or media accounts. The field requires more empirical and systematic research on all types of school shootings including single victim incidents, those that result in injury but not death and those that are successfully averted. We discuss current policies and practices related to school shootings and the role of mental health professionals in assessing risk and supporting surviving victims.

  2. PEMBELAJARAN LAY UP SHOOT MENGGUNAKAN MEDIA AUDIO VISUAL BASIC LAY UP SHOOT UNTUK MENINGKATKAN HASILBELAJAR LAY UP SHOOT PADA SISWA KELAS VIIIA SMP KANISIUS PATI TAHUN 2013/2014

    Directory of Open Access Journals (Sweden)

    Frendy Nurochwan Febryanto

    2015-01-01

    Full Text Available The purpose of this study was to determine the learning lay up shoot using basic audiovisual media shoot lay ups can improve learning outcomes shoot lay ups in class VIIIA Starch Canisius junior year 2013/2014 . This study uses Classroom Action Research ( CAR. The technique of collecting data through observation and assessment of learning outcomes shoot basketball lay up. Data analysis techniques used in this research is descriptive . At the end of the first cycle activity of teachers in teaching basic techniques lay up shoot using audio-visual media reaches 76.19%, whereas at the end of the first cycle of student activity during the learning process lay up shoot using audio-visualmediareaches78.57%. At the end of the second cycle of activity of teachers in teaching basic techniques lay up shoot using audio-visual media reaches 85.71%, whereas at the end of the second cycle of activity of students during the learning process lay up shoot using audio-visual media reaches 92.86%. Based on the results of the study it can be concluded that learning the lay-up shoot using basic audiovisual media shoot lay ups can improve student learning outcomes at Canisius junior class VIIIA Pati year 2013/2014.

  3. Adolescent mass shootings: developmental considerations in light of the Sandy Hook shooting.

    Science.gov (United States)

    Rice, Timothy R; Hoffman, Leon

    2015-05-01

    Adolescent mass shootings are a special subset of mass killings, which continue despite significant preventative public health efforts. It is often held that these individuals have few salient warning signs that could have been identified. This piece proposes that mass shootings committed by adolescent and post-adolescent young males must be understood from a developmental perspective. The hypothesis proposed in this paper is that such killings occur as the result of the adolescent's frustrated effort to progress along normative development. The goal of normative separation from maternal figures by the boy is presented as a potential risk factor when this goal is thwarted. Childhood case material from the perpetrator of a recent adolescent mass shooting, the Sandy Hook shooting, is discussed as an illustration of this hypothesis. Implications for public health measures and for individualized treatment are presented and developed.

  4. Effect of compost and humic acid in mobility and concentration of cadmium and chromium in soil and plant

    Directory of Open Access Journals (Sweden)

    A. Chaab

    2016-12-01

    Full Text Available The effect of compost and humic acid in mobility and concentration of cadmium and chromium in contaminated soil were investigated. Experiment was carried out with three levels of soil cadmium and chromium and two organic matters (compost and humic acid. The study was performed in a randomized complete block design with 3 replicates. Results indicated that application of organic substances enhanced movement of cadmium and chromium in soil column. Humic acid is more effective than compost on the mobility of cadmium and chromium in soil. Mobility of cadmium and chromium in the lower depths of soil column were increased. Cadmium and chromium concentration in shoots and roots enhanced due to increasing those concentration in soil and application of organic substances. Increase in cadmium in shoots can be attributed to the high mobility of this element in maize plant. Maize root chromium concentration was greater than shoot chromium concentration. Humic acid was more effective than compost as cadmium and chromium concentration in root and shoot was concerned. Low mobility of chromium in plant and accumulation of chromium in roots can be reasons of decreasing of chromium concentration in shoot of plant and its bioaccumulation.

  5. Effect of chickpea in association with Rhizobium to crop productivity and soil fertility

    Directory of Open Access Journals (Sweden)

    Botir Khaitov

    2016-04-01

    Full Text Available The growth, development and yield of chickpea (Cicer ariеtinum L. is strongly influenced by abiotic factors such as salinity and drought in the arid conditions. The use of efficient plant growth promoting bacteria in chickpea production is the best solution to overcome those stresses. In the present study, 10 chickpea rhizobial strains were isolated and purified from the nodules of chickpea genotype grown on middle salinated soils with different chickpea cultivation histories, 3 of them were more efficient in salt tolerance and showed higher nodulation abilities. Local chickpea genotype Uzbekistan-32 was inoculated with selected Rhizobium bacterial strains before planting them to the field condition. Inoculation of plants with strains Rhizobium sp. R4, R6 and R9 significantly increased shoot, root dry matter, and nodule number by 17, 12, and 20% above the uninoculated plants, respectively. The shoot length increased by 52%, root length by 43%, shoot dry weight by 36%, and root dry weight by 64%. Inoculation significantly increased the pod number by 28% and yield up to 55% as compared to control plant. The effective indigenous rhizobial strains isolated in this study from chickpeas on middle salinated soils of Uzbekistan have the characters of broad host range, high nodulation efficiency, efficient N fixation, great salt tolerance. Soil nitrogen, phosphorus and carbon content of the soil at the end of experiments were positive in all the treatments compare control. In this study, we are focused with consideration of the relationship between chickpea and its symbiotic nitrogen-fixing root nodule bacterial strains and how it functions to influence plant productivity and soil fertility.

  6. The use of 32P to study root growth of soybean as affected by soil compaction

    International Nuclear Information System (INIS)

    Sisworo, Elsje L.; Sisworo, Widjang H.; Syaukat, Sri Harti; Wemay, Johannis; Haryanto

    1996-01-01

    Two greenhouse and two field experiments have been conducted to study the effect of soil compaction on root and plant growth of soybean, by using 32 P in the form of carrier free KH 2 32 PO 4 solution. In the greenhouse experiment it was clearly shown that by increasing soil compaction the growth of roots and shoots was increasingly inhibited. The growth of roots was expressed in √% arcsin converted from 32 P activity (counts per minute, cpm) in the shoots and 32 P activity in the shoots (cpm) without convertion. Plant growth was expressed in plant height, number of leaves, dry weight of pods and shoots. In the field experiment, it was shown distinctively that root growth in the 15 cm soil depth was inhibited whith the increase of soil compaction. Similar with the greenhouse experiments the of plants of roots was expressed in cpm 32 P of roots, shoots, and pods, while, the growth of plants was expressed in plant height, number of pods, and dry weight of pods, seeds, and stover. (author). 19 refs, 4 tabs, 6 figs

  7. Shoot cuttings propagation of giant reed (Arundo donax L.) in water and moist soil: The path forward?

    Energy Technology Data Exchange (ETDEWEB)

    Ceotto, Enrico; Di Candilo, Mario [C.R.A. - Centro di Ricerca per le Colture Industriali, Via di Corticella 133, 40128 Bologna (Italy)

    2010-11-15

    Giant reed (Arundo donax L.) is a perennial rhizomatous grass that can be regarded as an ideal crop for bioenergy production, owing to several intrinsic characteristics. Despite to the promising yield results obtained in many plot experiments, the cultivation of giant reed at field scale is still a challenge. Owing to the floral sterility of the species, rhizome propagation has been predominantly used to establish field plots experiments, although this method is unpractical and monetarily expensive. Giant reed is a hydrophytic plant that typically spread in riparian systems by flood-mediated fragmentation and dispersal of vegetative propagules. Since giant reed propagation is strictly dependent on temporary abundance of water, this plant characteristic might be exploited for fostering the diffusion of giant reed as a bioenergy field crop. The objectives of this paper were: i) to disseminate some techniques for shoot cutting propagation of giant reed in water and in moist soil; ii) to address the critical points that remain to be solved for a widespread diffusion of this species as a bioenergy field crop. (author)

  8. Hydrolytic and ligninolytic enzyme activities in the Pb contaminated soil inoculated with litter-decomposing fungi.

    Science.gov (United States)

    Kähkönen, Mika A; Lankinen, Pauliina; Hatakka, Annele

    2008-06-01

    The impact of Pb contamination was tested to five hydrolytic (beta-glucosidase, beta-xylosidase, beta-cellobiosidase, alpha-glucosidase and sulphatase) and two ligninolytic (manganese peroxidase, MnP and laccase) enzyme activities in the humus layer in the forest soil. The ability of eight selected litter-degrading fungi to grow and produce extracellular enzymes in the heavily Pb (40 g Pb of kg ww soil(-1)) contaminated and non-contaminated soil in the non-sterile conditions was also studied. The Pb content in the test soil was close to that of the shooting range at Hälvälä (37 g Pb of kg ww soil(-1)) in Southern Finland. The fungi were Agaricus bisporus, Agrocybe praecox, Gymnopus peronatus, Gymnopilus sapineus, Mycena galericulata, Gymnopilus luteofolius, Stropharia aeruginosa and Stropharia rugosoannulata. The Pb contamination (40 g Pb of kg ww soil(-1)) was deleterious to all five studied hydrolytic enzyme activities after five weeks of incubation. All five hydrolytic enzyme activities were significantly higher in the soil than in the extract of the soil indicating that a considerable part of enzymes were particle bound in the soils. Hydrolytic enzyme activities were higher in the non-contaminated soil than in the Pb contaminated soil. Fungal inocula increased the hydrolytic enzyme activities beta-cellobiosidase and beta-glucosidase in non-contaminated soils. All five hydrolytic enzyme activities were similar with fungi and without fungi in the Pb contaminated soil. This was in line that Pb contamination (40 g Pb of kg ww soil(-1)) depressed the growth of all fungi compared to those grown without Pb in the soil. Laccase and MnP activities were low in both Pb contaminated and non-contaminated soil cultures. MnP activities were higher in soil cultures containing Pb than without Pb. Our results showed that Pb in the shooting ranges decreased fungal growth and microbial functioning in the soil.

  9. In-vitro morphogenesis of corn (Zea mays L.) : I. Differentiation of multiple shoot clumps and somatic embryos from shoot tips.

    Science.gov (United States)

    Zhong, H; Srinivasan, C; Sticklen, M B

    1992-07-01

    In-vitro methods have been developed to regenerate clumps of multiple shoots and somatic embryos at high frequency from shoot tips of aseptically-grown seedlings as well as from shoot apices of precociously-germinated immature zygotic embryos of corn (Zea mays L.). About 500 shoots were produced from a shoot tip after eight weeks of culture (primary culture and one subculture of four weeks) in darkness on Murashige and Skoog basal medium (MS) supplemented with 500 mg/L casein hydrolysate (CH) and 9 μM N(6)-benzyladenine (BA). In this medium, shoots formed in shoot tips as tightly packed "multiple shoot clumps" (MSC), which were composed of some axillary shoots and many adventitious shoots. When the shoot tips were cultured on MS medium containing 500 mg/L CH, 9 μM BA and 2.25 μM 2,4-dichlorophenoxyacetic acid (2,4-D), most of the shoots in the clumps were adventitious in origin. Similar shoot tips cultured on MS medium containing 500 mg/L CH, 4.5 μM BA and 2.25 μM 2,4-D regenerated many somatic embryos within eight weeks of culture. Somatic embryos were produced either directly from the shoot apical meristems or from calli derived from the shoots apices. Both the MSC and the embryos produced normal shoots on MS medium containing 2.25 μM BA and 1.8 μM indole-3-butyric acid (IBA). These shoots were rooted on MS medium containing 3.6 μM IBA, and fertile corn plants were grown in the greenhouse. The sweet-corn genotype, Honey N Pearl, was used for the experiments described above, but shoot-tip cultures from all of 19 other corn genotypes tested also formed MSC on MS medium containing 500 mg/L CH and 9 μM BA.

  10. Current perspectives on shoot branching regulation

    Directory of Open Access Journals (Sweden)

    Cunquan YUAN,Lin XI,Yaping KOU,Yu ZHAO,Liangjun ZHAO

    2015-03-01

    Full Text Available Shoot branching is regulated by the complex interactions among hormones, development, and environmental factors. Recent studies into the regulatory mecha-nisms of shoot branching have focused on strigolactones, which is a new area of investigation in shoot branching regulation. Elucidation of the function of the D53 gene has allowed exploration of detailed mechanisms of action of strigolactones in regulating shoot branching. In addition, the recent discovery that sucrose is key for axillary bud release has challenged the established auxin theory, in which auxin is the principal agent in the control of apical dominance. These developments increase our understan-ding of branching control and indicate that regulation of shoot branching involves a complex network. Here, we first summarize advances in the systematic regulatory network of plant shoot branching based on current information. Then we describe recent developments in the synthesis and signal transduction of strigolactones. Based on these considerations, we further summarize the plant shoot branching regulatory network, including long distance systemic signals and local gene activity mediated by strigolactones following perception of external envi-ronmental signals, such as shading, in order to provide a comprehensive overview of plant shoot branching.

  11. Soil type affects Pinus ponderosa var. scopulorum (Pinaceae) seedling growth in simulated drought experiments.

    Science.gov (United States)

    Lindsey, Alexander J; Kilgore, Jason S

    2013-08-01

    Effects of drought stress and media type interactions on growth of Pinus ponderosa var. scopulorum germinants were investigated. • 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. • 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.

  12. Improvement in soil and sorghum health following the application of polyacrylate polymers to a Cd-contaminated soil

    International Nuclear Information System (INIS)

    Guiwei, Q.; Varennes, A. de; Martins, L.L.; Mourato, M.P.; Cardoso, A.I.; Mota, A.M.; Pinto, A.P.; Goncalves, M.L.

    2010-01-01

    Contamination of soils with cadmium (Cd) is a serious global issue due to its high mobility and toxicity. We investigated the application of insoluble polyacrylate polymers to improve soil and plant health. Sorghum was grown in a Cd-contaminated sandy soil. Polyacrylate polymers at 0.2% (w/w) were added to half of the soil. Control soil without plants was also included in the experiment. Growth of sorghum was stimulated in the polymer-amended soil. The concentration of Cd in the shoots, and the activities of catalase and ascorbate peroxidase decreased in plants from polymer-amended soil compared with unamended control. The amount of CaCl 2 -extractable Cd in the polymer-amended soil was 55% of that in the unamended soil. The Cd extracted in sorghum shoots was 0.19 mg per plant grown on soil without polymer and 0.41 mg per plant grown on polymer-amended soil. The total amount of Cd removed from each pot corresponded to 1.5 and more than 6% of soil CaCl 2 -extractable Cd in unamended and polymer-amended soil, respectively. The activities of soil acid phosphatase, β-glucosidase, urease, protease and cellulase were greatest in polymer-amended soil with sorghum. In conclusion, the application of polyacrylate polymers to reduce the bioavailable Cd pool seems a promising method to enhance productivity and health of plants grown on Cd-contaminated soils.

  13. Phytoextraction of excess soil phosphorus

    International Nuclear Information System (INIS)

    Sharma, Nilesh C.; Starnes, Daniel L.; Sahi, Shivendra V.

    2007-01-01

    In the search for a suitable plant to be used in P phytoremediation, several species belonging to legume, vegetable and herb crops were grown in P-enriched soils, and screened for P accumulation potentials. A large variation in P concentrations of different plant species was observed. Some vegetable species such as cucumber (Cucumis sativus) and yellow squash (Cucurbita pepo var. melopepo) were identified as potential P accumulators with >1% (dry weight) P in their shoots. These plants also displayed a satisfactory biomass accumulation while growing on a high concentration of soil P. The elevated activities of phosphomonoesterase and phytase were observed when plants were grown in P-enriched soils, this possibly contributing to high P acquisition in these species. Sunflower plants also demonstrated an increased shoot P accumulation. This study shows that the phytoextraction of phosphorus can be effective using appropriate plant species. - Crop plants such as cucumber, squash and sunflower accumulate phosphorus and thus can be used in the phytoextraction of excess phosphorus from soils

  14. Phytoextraction of excess soil phosphorus

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Nilesh C. [Department of Biology, Western Kentucky University, 1906 College Heights Boulevard 11080, Bowling Green, KY 42101-1080 (United States); Starnes, Daniel L. [Department of Biology, Western Kentucky University, 1906 College Heights Boulevard 11080, Bowling Green, KY 42101-1080 (United States); Sahi, Shivendra V. [Department of Biology, Western Kentucky University, 1906 College Heights Boulevard 11080, Bowling Green, KY 42101-1080 (United States)]. E-mail: shiv.sahi@wku.edu

    2007-03-15

    In the search for a suitable plant to be used in P phytoremediation, several species belonging to legume, vegetable and herb crops were grown in P-enriched soils, and screened for P accumulation potentials. A large variation in P concentrations of different plant species was observed. Some vegetable species such as cucumber (Cucumis sativus) and yellow squash (Cucurbita pepo var. melopepo) were identified as potential P accumulators with >1% (dry weight) P in their shoots. These plants also displayed a satisfactory biomass accumulation while growing on a high concentration of soil P. The elevated activities of phosphomonoesterase and phytase were observed when plants were grown in P-enriched soils, this possibly contributing to high P acquisition in these species. Sunflower plants also demonstrated an increased shoot P accumulation. This study shows that the phytoextraction of phosphorus can be effective using appropriate plant species. - Crop plants such as cucumber, squash and sunflower accumulate phosphorus and thus can be used in the phytoextraction of excess phosphorus from soils.

  15. The Value Range of Contact Stiffness Factor between Pile and Soil Based on Penalty Function

    Science.gov (United States)

    Chen, Sandy H. L.; Wu, Xinliu

    2018-03-01

    The value range of contact stiffness factor based on penalty function is studied when we use finite element software ANSYS to analyze contact problems, take single pile and soil of a certain project for example, the normal contact between pile and soil is analyzed with 2D simplified model in horizontal load. The study shows that when adopting linear elastic model to simulate soil, the maximum contact pressure and penetration approach steady value as the contact stiffness factor increases. The reasonable value range of contact stiffness factor reduces as the underlying element thickness decreases, but the rule reverses when refers to the soil stiffness. If choose DP model to simulate soil, the stiffness factor should be magnified 100 times compares to the elastic model regardless of the soil bears small force and still in elastic deformation stage or into the plastic deformation stage. When the soil bears big force and into plastic deformation stage, the value range of stiffness factor relates to the plastic strain range of the soil, and reduces as the horizontal load increases.

  16. Root-shoot relationships in four strains of field-grown Erianthus arundinaceus at seedling stage

    Directory of Open Access Journals (Sweden)

    Fumitaka Shiotsu

    2016-01-01

    Full Text Available The production of cellulosic bioethanol from non-edible plants is a potential countermeasure against global warming. Erianthus species provide cellulosic raw material for bioethanol because they have high biomass productivity and high tolerance to environmental stress, associated with their large, deep root systems. However, it is difficult to select Erianthus species for breeding by direct observation of their root systems because the roots are widely dispersed in the soil. Instead, we examined shoot morphological traits that could be closely related to root morphology to find effective reference indices for selection. The potential to evaluate root structure and function in Erianthus according to bleeding rate was also examined. An analysis of root–shoot relationships in seedlings indicated that root number and mean length were closely related to stem number and diameter, respectively. These results suggest that root–shoot relationships may provide useful criteria for selective breeding of root systems in Erianthus.

  17. Giant panda foraging and movement patterns in response to bamboo shoot growth.

    Science.gov (United States)

    Zhang, Mingchun; Zhang, Zhizhong; Li, Zhong; Hong, Mingsheng; Zhou, Xiaoping; Zhou, Shiqiang; Zhang, Jindong; Hull, Vanessa; Huang, Jinyan; Zhang, Hemin

    2018-03-01

    Diet plays a pivotal role in dictating behavioral patterns of herbivorous animals, particularly specialist species. The giant panda (Ailuropoda melanoleuca) is well-known as a bamboo specialist. In the present study, the response of giant pandas to spatiotemporal variation of bamboo shoots was explored using field surveys and GPS collar tracking. Results show the dynamics in panda-bamboo space-time relationships that have not been previously articulated. For instance, we found a higher bamboo stump height of foraged bamboo with increasing elevation, places where pandas foraged later in spring when bamboo shoots become more fibrous and woody. The time required for shoots to reach optimum height for foraging was significantly delayed as elevation increased, a pattern which corresponded with panda elevational migration patterns beginning from the lower elevational end of Fargesia robusta distribution and gradually shifting upward until the end of the shooting season. These results indicate that giant pandas can respond to spatiotemporal variation of bamboo resources, such as available shoots. Anthropogenic interference of low-elevation F. robusta habitat should be mitigated, and conservation attention and increased monitoring should be given to F. robusta areas at the low- and mid-elevation ranges, particularly in the spring shooting season.

  18. Influence of Soil Based Growing Media on Vegetative Propagation of Selected Cultivars of Olea Europaea

    International Nuclear Information System (INIS)

    Ahmed, M. I.; Ashraf, M. I.; Malik, S. U.; Husaain, Q.

    2016-01-01

    Pothwar region of Pakistan is a natural habitat of Olea spp. There is a high demand of certified olive plants to establish olive orchids in the region, because native wild species are non-fruit bearing. Plants of certified fruit bearing olive (Olea europaea L.) cultivars are rarely available. Vegetative propagation of olive is highly responsive to texture of soil based growing media. This study examined the effect of growing media composition (soil texture and nutrients) on vegetative propagation of five cultivars of olive. The experiment was carried out in randomized complete block design (RCBD) with two factors factorial having 25 repeats of each four treatments. Plant growth and survival data were collected and analyzed for the influence of soil attributes. In sandy loam soil, cv. Bari-1 had 82 percent plant survival, highest number of roots per plant (3.5), and longest root length (13.01 cm). Highest number of shoots per plant (4.25) and maximum shoot length (15.64 cm) were also recorded for Bari-1 with sandy loam growing media. Silt loam soil is least suitable growing media for vegetative propagation of olive. In the silt loam soil, plants survival rate was 59 percent for cv. Gemlik, number of roots per plant was 1.5 for cv. Ottobrattica, minimum root length 5.65 cm, minimum number of shoots per plant one, and minimum shoot length 7.42 cm were recorded for cv. Pendolino with silt loam soil. Results suggested that sandy loam growing media is better than the others for vegetative propagation of olive. Cultivar Bari-1 performed better than the others examined in this study by indicating highest (1) survival percentage, (2) root and shoot length, and (3) number of roots and shoots produced within a specific period of time. (author)

  19. Highly charged swelling mica reduces Cu bioavailability in Cu-contaminated soils

    Energy Technology Data Exchange (ETDEWEB)

    Stuckey, Jason W. [Department of Crop and Soil Sciences, Pennsylvania State University, 116 ASI Building, University Park, PA 16802 (United States); Neaman, Alexander [Facultad de Agronomia, P. Universidad Catolica de Valparaiso, Centro Regional de Estudios en Alimentos Saludables (Chile); Ravella, Ramesh; Komarneni, Sridhar [Department of Crop and Soil Sciences, Pennsylvania State University, 116 ASI Building, University Park, PA 16802 (United States); Martinez, Carmen Enid [Department of Crop and Soil Sciences, Pennsylvania State University, 116 ASI Building, University Park, PA 16802 (United States)], E-mail: cem17@psu.edu

    2009-01-15

    This is the first test of a highly charged swelling mica's (Na-2-mica) ability to reduce the plant-absorbed Cu in Cu-contaminated soils from Chile. Perennial ryegrass (Lolium perenne L.) was grown in two acid soils (Sector 2: pH 4.2, total Cu = 172 mg Cu kg{sup -1} and Sector 3: pH 4.2, total Cu = 112 mg Cu kg{sup -1}) amended with 0.5% and 1% (w/w) mica, and 1% (w/w) montmorillonite. At 10 weeks of growth, both mica treatments decreased the shoot Cu of ryegrass grown in Sector 2 producing shoot Cu concentrations above 21-22 mg Cu kg{sup -1} (the phytotoxicity threshold for that species), yet the mica treatments did not reduce shoot Cu concentrations when grown in Sector 3, which were at a typical level. The mica treatments improved shoot growth in Sector 3 by reducing free and extractable Cu to low enough levels where other nutrients could compete for plant absorption and translocation. In addition, the mica treatments improved root growth in both soils, and the 1% mica treatment reduced root Cu in both soils. This swelling mica warrants further testing of its ability to assist re-vegetation and reduce Cu bioavailability in Cu-contaminated surface soils. - In situ remediation of Cu-contaminated soils with a synthetic mica (Na-2-mica) will aid in re-vegetative efforts.

  20. Shooting mechanisms in nature

    NARCIS (Netherlands)

    Sakes, Aimée; Wiel, van der Marleen; Henselmans, Paul W.J.; Leeuwen, van Johan L.; Dodou, Dimitra; Breedveld, Paul

    2016-01-01

    Background In nature, shooting mechanisms are used for a variety of purposes, including prey capture, defense, and reproduction. This review offers insight into the working principles of shooting mechanisms in fungi, plants, and animals in the light of the specific functional demands that these

  1. Empirical models in the description of prickly pear shoot (Nopal drying kinetics

    Directory of Open Access Journals (Sweden)

    Emmanuel M. Pereira

    Full Text Available ABSTRACT The objective of this study was to describe the technological process involved in the drying kinetics of fresh-cut prickly pear shoots through numerical and analytical solutions. Shoots of two different prickly pear species were used, ‘Gigante’ and ‘Miúda’. Drying was performed at different temperatures (50, 60, 70 and 80 °C and weighing procedures were made continuously. The experimental data were expressed as moisture ratio. The Page model showed the best fit to the drying kinetics of minimally processed ‘Gigante’ and ‘Miúda’ prickly pear shoots, with the best coefficients of determination and Chi-square. Peleg and Wang & Singh models can not be used to simulate the drying of ‘Gigante’ and ‘Miúda’ prickly pear shoots within the evaluated range of temperatures, showing an incoherent graphic pattern.

  2. Phytoremediation of cadmium contaminated soils by tuberose

    International Nuclear Information System (INIS)

    Ramana, S.; Biswas, A.K.; Singh, A.B.; Ajay; Ahirwar, N.K.; Behera, S.K.; Subba Rao, A.; Naveen Kumar, P.

    2012-01-01

    The potential of three varieties of tuberose (Prajwal, Shringar and Mexican single) for phytoremediation of soil contaminated with cadmium was evaluated by subjecting the plants to five levels of Cd (0, 25, 50, 75 and 100 mg kg -1 soil). Applied Cd did not produce any toxic symptoms in all the three varieties of tuberose except marginal reduction in the photosynthesis rate and total dry weight beyond 50 mg Cd kg -1 soil. The study showed that tuberose possessed the typical ability of Cd hyper accumulator characterized by (1) accumulation of Cd in the shoots of the plant exceeding the critical judging standard i.e., 100 μg g -1 DW and (2) ratio of Cd in the shoots to bulbs >1. It was concluded that tuberose may be an effective accumulator plant for phytoremediation of cadmium polluted soils. (author)

  3. 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.

  4. Mass shooting and mass media : does media coverage of mass shootings inspire copycat crimes?

    OpenAIRE

    Mesoudi, A.

    2013-01-01

    In December 2012, twenty elementary school children and six adult staff members were shot and killed by a single individual at a school in Connecticut. Although this horrific event was met with widespread shock, Americans are sadly all too familiar with such mass shootings. From Columbine in 1999, to Virginia Tech in 2007, to the Colorado cinema shootings earlier in 2012, mass shootings seem to occur with alarming regularity. And although they appear to afflict the United States more than mos...

  5. Effects of gamma irradiation on the shoot length of Cicer seeds

    International Nuclear Information System (INIS)

    Toker, Cengiz; Uzun, Bulent; Canci, Huseyin; Oncu Ceylan, F.

    2005-01-01

    The effects of radiation on the shoot and root lengths of germinated seedling of irradiated seeds of Cicer species, i.e. three kabuli types and four desi types of cultivated chickpea (Cicer arietinum Ladiz.) and 2 annual wild types (C. reticulatum Ladiz. and C. bijugum K.H. Rech.) were investigated. The seeds were irradiated with a 60 Co gamma source using 0, 200, 300 and 400 Gy doses at 1.66 kGy h -1 . At 200 Gy minor effects could be observed, but at 400 Gy an obvious depression of shoot length was observed. The kabuli types were more affected than the desi ones. The critical dose that prevented the shoot and root elongation varied among species and also ranged from genotypes to genotype within species

  6. Effects of different fertilizers on growth and nutrient uptake of Lolium multiflorum grown in Cd-contaminated soils.

    Science.gov (United States)

    Liu, Mohan; Li, Yang; Che, Yeye; Deng, Shaojun; Xiao, Yan

    2017-10-01

    This study aimed to explore the effects of different fertilizers and their combinations on growth and nutrient and Cd uptake of Lolium multiflorum. Compared with control treatment, chemical fertilizer, organic manure, and their conjunctions with biofertilizer increased shoot biomass. Biofertilizers were found to cause significant reductions in shoot biomass of plants grown in organic manure-treated and control soil. Decreased soil-available N and P and shoot N and K concentrations in biofertilizer amendment treatments indicated that plant growth and nutrient absorption might be negatively affected under nutrient deficiency conditions. Elevated shoot biomasses contributed to the highest shoot Cd contents in chemical fertilizer and chemical fertilizer + biofertilizer treatments among all treatments. But the maximum translocation efficiency occurred in biofertilizer + chemical fertilizer + organic manure treatment, followed by organic manure and chemical fertilizer + organic manure treatments. Based on the results, we can conclude that the application of only the biofertilizer Bacillus subtilis should be avoided in nutrient-limited soils. Chemical fertilizer application could benefit the amount of Cd in shoots, and organic manure application and its combinations could result in the higher translocation efficiency.

  7. Mineral concentrations of forage legumes and grasses grown in acidic soil amended with flue gas desulfurization products

    Energy Technology Data Exchange (ETDEWEB)

    Clark, R.B.; Baligar, V.C. [USDA ARS, Beltsville, MD (USA). Beltsville Agricultural Research Center West

    2003-07-01

    Considerable quantities of flue gas desulfurization products (FGDs) are generated when coal is burned for production of electricity, and these products have the potential to be reused rather than discarded. Use of FGDs as soil amendments could be important in overall management of these products, especially on acidic soils. Glasshouse studies were conducted to determine shoot concentrations of calcium (Ca), sulfur (S), potassium (K), magnesium (Mg), phosphorus (P), boron (B), zinc (Zn), copper (Cu), manganese (Mn), iron (Fe), aluminum (Al), sodium (Na), molybdenum (Mo), nickel (Ni), cadmium (Cd), chromium (Cr), and lead (Pb) in alfalfa (Medicago sativa), white clover (Trifolium repens), orchardgrass (Dacrylis glomerata), tall fescue (Festuca arundinacea), switchgrass (Panicum virgatum), and eastern gamagrass (Tripsacum dactyloides) grown in acidic (pH 4) soil (Typic Hapludult) amended with various levels of three FGDs and the control compounds CaCO{sub 3}, CaSO{sub 3}, and CaSO{sub 4}. Shoot concentrations of Ca, S, Mg, and B generally increased as levels of soil applied FGD increased. Concentrations of Mn, Fe, Zn, Cu were lower in shoots, especially when soil pH was high ({gt}7). Shoot concentrations of the trace elements Mo, Ni, Cd, Cr, and Pb were not above those reported as normal for foliage. Overall concentrations of most minerals remained near normal for shoots when plants were grown in FGD amended acidic soil.

  8. Growth of cowpea plants inoculated with Rhizobium in a saline-sodic soil after application of gypsum

    Directory of Open Access Journals (Sweden)

    Angela Jessyka Pereira Brito Fontenele

    Full Text Available Two experiments were carried out with the aim of evaluating the growth of cowpea cultivated in saline-sodic soils corrected with gypsum: one experiment in the laboratory, to identify the best level of gypsum for the correction of the saline-sodic soils of the state of Pernambuco, Brazil; and the other in a greenhouse, after correction of the soils. As the test plant, the cowpea cultivar pele de moça, inoculated with Rhizobium strain BR3267 was used. The experiments were arranged in a randomised block design in a 2 x 5 factorial arrangement, two soils and five levels of the gypsum requirement (GR, equivalent to 50, 100, 150, 200 and 250% of the GR of the soil, as determined by the Schoonover M-1 method, with five replications. The following were evaluated: electrical conductivity of the soil saturation extract (EC, soil exchangeable sodium and percentage of soil exchangeable sodium (ESP, number of nodules (NN, nodule dry weight (NDW, shoot dry weight (SDW, shoot height (PH and nitrogen concentration (N in the shoots. Application of 100% of the GR, followed by the enough water for leaching, was effective for the correction of soil sodicity. The application of increasing levels of soil GR resulted in an increase in the number of nodules, dry weight of the nodules and shoots, and the height and levels of N absorbed by the plants in soil S2. In soil S1, the use of levels of 200 and 250% of soil the GR caused a decrease in all the variables under study.

  9. Improved recovery of cryotherapy-treated shoot tips following thermotherapy of in vitro-grown stock shoots of raspberry (Rubus idaeus L.).

    Science.gov (United States)

    Wang, Qiaochun; Valkonen, Jari P T

    2009-01-01

    Raspberry bushy dwarf virus (RBDV) can be efficiently eradicated from raspberry plants (Rubus idaeus) by a procedure combining thermotherapy and cryotherapy. However, the bottleneck of this procedure is that, following thermotherapy, cryopreserved shoot tips become chlorotic during regrowth and eventually die after several subcultures. In addition, survival of heat-treated stock shoots and recovery of cryopreserved shoot tips following thermotherapy are low. The present study focused towards improving regrowth of cryopreserved raspberry shoot tips following thermotherapy. Results showed that preconditioning stock shoots with salicylic acid (SA; 0.01-0.1 mM) markedly increased survival of stock shoots after 4 weeks of thermotherapy. Regrowth of cryopreserved shoot tips following thermotherapy was also significantly enhanced when SA (0.05-0.1 mM) was used for preconditioning stock shoots. Addition of either Fe-ethylenediaminetetracetic acid (Fe-EDTA, 50 mg per L) or Fe-ethylenediaminedi(o)hydroxyphenylacetic acid (Fe-EDDHA, 50 mg per L) to post-culture medium strongly promoted regrowth and totally prevented chlorosis of shoots regenerated from cryopreserved shoot tips following thermotherapy. Using the parameters optimized in the present study, about 80 percent survival of heat-treated stock shoots and about 33 percent regrowth of cryopreserved shoot tips following thermotherapy were obtained. Morphology of plants regenerated from cryopreserved shoot tips following thermotherapy was identical to that of control plants, based on observations of leaf shape and size, internode length and plant height. Optimization of the thermotherapy procedure followed by cryotherapy will facilitate the wider application of this technique to eliminate viruses which can invade meristems.

  10. High Frequency Multiple Shoot Induction of Curculigo orchioides Gaertn.: Shoot Tip V/S Rhizome Disc

    Directory of Open Access Journals (Sweden)

    K. S. Nagesh

    2008-09-01

    Full Text Available Curculigo orchioides Gaertn. is an endangered medicinal plant with anticancer properties. The rhizome and tuberous roots of the plant have been used extensively in India in indigenous medicine. Due to its multiple uses, the demand for Curculigo orchioides is constantly on the rise; however, the supply is rather erratic and inadequate. Destructive harvesting, combined with habitat destruction in the form of deforestation has aggravated the problem. The plant is now considered ‘endangered’ in its natural habitat. Therefore, the need for conservation of this plant is crucial. Here, we describe a successful protocol for multiple shoot induction of C. orchioides using shoot tip and rhizome disc. We find that proximal rhizome discs are optimal for high frequency shoot bud formation than shoot tip and distal rhizome disc. We observed a synergistic effect between 6-benzylaminopurine (BAP and kinetin (KN (each at 1 mg/L on the regeneration of shoot buds from proximal rhizome disc than shoot tip explant. Optimum root induction was achieved on half-strength MS liquid medium supplemented with 1 mg/L of indole-3-butyric acid (IBA. The in vitro raised plantlets were acclimatized in green house and successfully transplanted to natural condition with 90% survival.

  11. EDDS and EDTA-enhanced phytoextraction of metals from artificially contaminated soil and residual effects of chelant compounds

    Energy Technology Data Exchange (ETDEWEB)

    Luo Chunling [Department of Civil and Structural Engineering, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong (China); Shen Zhenguo [Department of Civil and Structural Engineering, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong (China); College of Life Sciences, Nanjing Agricultural University, Nanjing 210095 (China); Lou Laiqing [College of Life Sciences, Nanjing Agricultural University, Nanjing 210095 (China); Li Xiangdong [Department of Civil and Structural Engineering, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong (China)]. E-mail: cexdli@polyu.edu.hk

    2006-12-15

    The potential of 18 different plants to be used in the chemically enhanced phytoextraction of Cu, Pb, Zn and Cd was assessed using pot experiments. Chrysanthemum coronarium L. was the species most sensitive to the application of EDTA, and had the highest enhancement of Cu and Pb concentrations in its shoots. Compared with EDTA, EDDS was more effective in enhancing the concentration of Cu in the shoots of Chrysanthemum coronarium L. and Zea mays L. grown on multi-metal contaminated soils. The EDTA-treated soil still had a significant ability to enhance the concentrations of Cu and Pb in the shoots of Zea mays L. six months after the chelant treatment. However, the EDDS-treated soil did not have any effect in enhancing the concentrations of metals in the shoots of Zea mays L. in the second crop test. The results may indicate that EDDS biodegrades more rapidly than EDTA in soil and is better in limiting potential metal leaching. - Chrysanthemum coronarium L. was the most sensitive species to the application of chelants, and EDDS biodegrades much more rapidly than EDTA in soil.

  12. EDDS and EDTA-enhanced phytoextraction of metals from artificially contaminated soil and residual effects of chelant compounds

    International Nuclear Information System (INIS)

    Luo Chunling; Shen Zhenguo; Lou Laiqing; Li Xiangdong

    2006-01-01

    The potential of 18 different plants to be used in the chemically enhanced phytoextraction of Cu, Pb, Zn and Cd was assessed using pot experiments. Chrysanthemum coronarium L. was the species most sensitive to the application of EDTA, and had the highest enhancement of Cu and Pb concentrations in its shoots. Compared with EDTA, EDDS was more effective in enhancing the concentration of Cu in the shoots of Chrysanthemum coronarium L. and Zea mays L. grown on multi-metal contaminated soils. The EDTA-treated soil still had a significant ability to enhance the concentrations of Cu and Pb in the shoots of Zea mays L. six months after the chelant treatment. However, the EDDS-treated soil did not have any effect in enhancing the concentrations of metals in the shoots of Zea mays L. in the second crop test. The results may indicate that EDDS biodegrades more rapidly than EDTA in soil and is better in limiting potential metal leaching. - Chrysanthemum coronarium L. was the most sensitive species to the application of chelants, and EDDS biodegrades much more rapidly than EDTA in soil

  13. Salinization/sodification of soil and physiological dynamics of sunflower irrigated with saline–sodic water amending by potassium and farm yard manure

    Directory of Open Access Journals (Sweden)

    M. Ashraf

    2017-12-01

    Full Text Available Sunflower (Helianthus annuus L. plants were grown with saline–sodic water (SSW by treating with potassium (K @ 100 and 200 mg K2O kg−1 soil and farm yard manure (FYM @ 5 and 10% of soil, w/w. Irrigation with untreated SSW caused soil salinization/sodification, leading to an increase in electrical conductivity (EC of 165% and sodium adsorption ratio (SAR 100% with the subsequent increase of 736% in shoot Na+, a decrease of 52% in shoot K+ and 94% in shoot K+:Na+ratio compared to canal water. SSW also decreased physiological activities: 31% relative water content (RWC, 34% membrane stability index (MSI, 51% protein, 33% chlorophyll and 58% photosynthetic rate compared to canal water. Integrated application of K and FYM, at higher level, decreased soil EC by 54% and SAR 43%, and shoot Na+ 57% with a corresponding improvement in soil organic matter 166%, shoot K+ 360%, shoot K+:Na+ratio 987%, RWC 34%, MSI 37%, protein 60%, photosynthetic rate 102%, superoxide dismutase 92%, peroxidase 78% and catalase 52% compared to SSW without K and/or FYM. In conclusion, exogenous application of K and FYM could be a promising approach to use brackish water in agriculture on a sustainable basis.

  14. Soil type affects Pinus ponderosa var. scopulorum (Pinaceae) seedling growth in simulated drought experiments1

    Science.gov (United States)

    Lindsey, Alexander J.; Kilgore, Jason S.

    2013-01-01

    • 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. PMID:25202578

  15. Role of Streptomyces pactum in phytoremediation of trace elements by Brassica juncea in mine polluted soils.

    Science.gov (United States)

    Ali, Amjad; Guo, Di; Mahar, Amanullah; Wang, Zhen; Muhammad, Dost; Li, Ronghua; Wang, Ping; Shen, Feng; Xue, Quanhong; Zhang, Zengqiang

    2017-10-01

    The industrial expansion, smelting, mining and agricultural practices have increased the release of toxic trace elements (TEs) in the environment and threaten living organisms. The microbe-assisted phytoremediation is environmentally safe and provide an effective approach to remediate TEs contaminated soils. A pot experiment was conducted to test the potential of an Actinomycete, subspecies Streptomyces pactum (Act12) along with medical stone compost (MSC) by growing Brassica juncea in smelter and mines polluted soils of Feng County (FC) and Tongguan (TG, China), respectively. Results showed that Zn (7, 28%), Pb (54, 21%), Cd (16, 17%) and Cu (8, 10%) uptake in shoot and root of Brassica juncea was pronounced in FC soil. Meanwhile, the Zn (40, 14%) and Pb (82, 15%) uptake in the shoot and root were also increased in TG soil. Shoot Cd uptake remained below detection, while Cu decreased by 52% in TG soil. The Cd and Cu root uptake were increased by 17% and 33%, respectively. Results showed that TEs uptake in shoot increased with increasing Act12 dose. Shoot/root dry biomass, chlorophyll and carotenoid content in Brassica juncea were significantly influenced by the application of Act12 in FC and TG soil. The antioxidant enzymatic activities (POD, PAL, PPO and CAT) in Brassica juncea implicated enhancement in the plant defense mechanism against the TEs induced stress in contaminated soils. The extraction potential of Brasssica was further evaluated by TF (translocation factor) and MEA (metal extraction amount). Based on our findings, further investigation of Act12 assisted phytoremediation of TEs in the smelter and mines polluted soil and hyperaccumulator species are suggested for future studies. Copyright © 2017. Published by Elsevier Inc.

  16. Micropore surface area of alkali-soluble plant macromolecules (humic acids) drives their decomposition rates in soil.

    Science.gov (United States)

    Papa, Gabriella; Spagnol, Manuela; Tambone, Fulvia; Pilu, Roberto; Scaglia, Barbara; Adani, Fabrizio

    2010-02-01

    Previous studies suggested that micropore surface area (MSA) of alkali-soluble bio-macromolecules of aerial plant residues of maize constitutes an important factor that explains their humification in soil, that is, preservation against biological degradation. On the other hand, root plant residue contributes to the soil humus balance, as well. Following the experimental design used in a previous paper published in this journal, this study shows that the biochemical recalcitrance of the alkali-soluble acid-insoluble fraction of the root plant material, contributed to the root maize humification of both Wild-type maize plants and its corresponding mutant brown midrib (bm3), this latter characterized by reduced lignin content. Humic acids (HAs) existed in root (root-HAs) were less degraded in soil than corresponding HAs existed in shoot (shoot-HAs): shoot-HAs bm3 (48%)>shoot-HAs Wild-type (37%)>root-HAs Wild-type (33%)>root-HAs bm3 (22%) (degradability shown in parenthesis). These differences were related to the MSA of HAs, that is, root-HAs having a higher MSA than shoot-HAs: shoot-HAs bm3 (41.43+/-1.2m(2)g(-1))<shoot-HAs Wild-type (43.43+/-1.7m(2)g(-1))shoots and the results of this study, it was possible to find a very good correlation between degradability of HAs and HA-MSAs (r=-0.88, P<0.08, n=4), confirming that MSA was able to explain bio-macromolecules recalcitrance in soil.

  17. ROLE OF SOME CHEMICAL MATERIALS ON THE PHYTO-EXTRACTION OF HEAVY METALS FROM CONTAMINATED SOILS WITH SUNFLOWER PLANTS (HELIANTHUS ANNUUS)

    International Nuclear Information System (INIS)

    ABD EL-BARY, S.A.; EL-NAKA, E.A.; RIZK, M.A.; LOTFY, S.M.

    2009-01-01

    Chelation and complexation of heavy metals were evaluated as practical ways to solubilize, detoxify and enhance heavy metals accumulation by plants. Sunflower (Helianthus annuus) was selected as potential heavy metals accumulator for metals phyto-extraction in two selected soils (clayey and sandy). To enhance metals phyto-extraction, ammonium nitrate and organic chelates such as EDTA and citric acid were added to soils at the rates from 0 to 20 mmol/kg soil as extracting solutions and applied to the soil by mixing thoroughly before planting. Dry matter production and metals concentrations in shoots and roots and soil pH were measured after 60 days.Plant dry matter production and metals accumulation were varied with soil contamination, chelate / organic acid form and rate, and soil type. The highest metals concentration was obtained in plants grown on clayey soil, however, the lowest content was observed in case of sandy soil. Addition of citric acid increased metals accumulation and translocation to the shoots significantly. Addition of 20 mmol/kg of citric acid to clayey soils increased metals concentration in shoots several folds of magnitude, but addition of ammonium nitrate had little effect on metal translocation to shoots. Citric acid was the most effective chelate in plant accumulation of tested metals.

  18. Multiple Shooting and Time Domain Decomposition Methods

    CERN Document Server

    Geiger, Michael; Körkel, Stefan; Rannacher, Rolf

    2015-01-01

    This book offers a comprehensive collection of the most advanced numerical techniques for the efficient and effective solution of simulation and optimization problems governed by systems of time-dependent differential equations. The contributions present various approaches to time domain decomposition, focusing on multiple shooting and parareal algorithms.  The range of topics covers theoretical analysis of the methods, as well as their algorithmic formulation and guidelines for practical implementation. Selected examples show that the discussed approaches are mandatory for the solution of challenging practical problems. The practicability and efficiency of the presented methods is illustrated by several case studies from fluid dynamics, data compression, image processing and computational biology, giving rise to possible new research topics.  This volume, resulting from the workshop Multiple Shooting and Time Domain Decomposition Methods, held in Heidelberg in May 2013, will be of great interest to applied...

  19. Cesium-137 in soil texture fractions and its impact on Cesium-137 soil-to-plant transfer

    International Nuclear Information System (INIS)

    Gerzabek, M.H.; Mohamad, S.A.; Mueck, K.

    1992-06-01

    Field studies at two sites contaminated by the Chernobyl fallout showed 137 Cesium (Cs) soil-to-plant transfer factors in wheat, rye and potato. Transfer values ranged from 0.0017 (potato tuber) to 0.07 (wheat straw). Generally transfer coefficients in cereal grains and potato tubers were significantly below the values of the shoots. A comparison of the two sites led to the conclusion that for all plants investigated 137 Cs transfer factors were higher in Lower Austria (Calcic Chernozem) than in Upper Austria (Eutric Cambisol). The specific activities of the texture fractions of the two soil types increased from sand to silt and clay. In the Calcic Chernozem the ratio of the 137 Cs activity in the silt fraction to the total activity in the soil was considerably higher than in the Eutric Cambisol. At the same time extractability of 137 Cs from the silt fraction of the latter soil was clearly lower. Both results mainly were attributed to the differences between the soils according to the organic matter content of the silt fractions, the Calcic Chernozem being seven times higher. Therefore, the differences in the 137 Cs-soil-to-plant transfer can be attributed partly to these soil characteristics. (authors)

  20. SPATIAL CORRELATION BETWEEN PHYSICAL PROPERTIES OF SOIL AND WEEDS IN TWO MANAGEMENT SYSTEMS

    Directory of Open Access Journals (Sweden)

    Valter Roberto Schaffrath

    2015-02-01

    Full Text Available The spatial correlation between soil properties and weeds is relevant in agronomic and environmental terms. The analysis of this correlation is crucial for the interpretation of its meaning, for influencing factors such as dispersal mechanisms, seed production and survival, and the range of influence of soil management techniques. This study aimed to evaluate the spatial correlation between the physical properties of soil and weeds in no-tillage (NT and conventional tillage (CT systems. The following physical properties of soil and weeds were analyzed: soil bulk density, macroporosity, microporosity, total porosity, aeration capacity of soil matrix, soil water content at field capacity, weed shoot biomass, weed density, Commelina benghalensis density, and Bidens pilosa density. Generally, the ranges of the spatial correlations were higher in NT than in CT. The cross-variograms showed that many variables have a structure of combined spatial variation and can therefore be mapped from one another by co-kriging. This combined variation also allows inferences about the physical and biological meanings of the study variables. Results also showed that soil management systems influence the spatial dependence structure significantly.

  1. Iron Availability in Tropical Soils and Iron Uptake by Plants

    Directory of Open Access Journals (Sweden)

    Guilherme Furlan Mielki

    Full Text Available ABSTRACT Given the increase in crop yields and the expansion of agriculture in low fertility soils, deficiency of micronutrients, such as iron, in plants grown in tropical soils has been observed. The aim of this study was to evaluate Fe availability and Fe uptake by corn (Zea mays L. plants in 13 different soils, at two depths. Iron was extracted by Mehlich-1, Mehlich-3, and CaCl2 (Fe-CC and was fractionated in forms related to low (Feo and high (Fed crystallinity pedogenic oxyhydroxides, and organic matter (Fep using ammonium oxalate, dithionite-citrate, and sodium pyrophosphate, respectively. In order to relate Fe availability to soil properties and plant growth, an experiment was carried out in a semi-hydroponic system in which part of the roots developed in a nutrient solution (without Fe and part in the soil (the only source of Fe. Forty-five days after seeding, we quantified shoot dry matter and leaf Fe concentration and content. Fed levels were high, from 5 to 132 g kg-1, and Feo and Fe-CC levels were low, indicating the predominance of Fe as crystalline oxyhydroxides and a low content of Fe readily available to plants. The extraction solutions showed significant correlations with various soil properties, many common to both, indicating that they act similarly. The correlation between the Mehlich-1 and Mehlich-3 extraction solutions was highly significant. However, these two extraction methods were inefficient in predicting Fe availability to plants. There was a positive correlation between dry matter and Fe levels in plant shoots, even within the ranges considered adequate in the soil and in the plant. Dry matter production and leaf Fe concentration and content were positively correlated with Fep concentration, indicating that the Fe fraction related to soil organic matter most contributes to Fe availability to plants.

  2. The Binomial Distribution in Shooting

    Science.gov (United States)

    Chalikias, Miltiadis S.

    2009-01-01

    The binomial distribution is used to predict the winner of the 49th International Shooting Sport Federation World Championship in double trap shooting held in 2006 in Zagreb, Croatia. The outcome of the competition was definitely unexpected.

  3. Effect of soil acidification on root growth, nutrient and water uptake

    International Nuclear Information System (INIS)

    Marschner, H.

    1989-01-01

    Soil acidification poses various types of stress to plants, especially Al and H + toxicity in roots and Mg and Ca deficiency in roots and shoots. The importance of the various types of stress varies with plant species, location and time. Average data of the chemical composition of the bulk soil or of the molar Ca/Al or Mg/Al ratios in the soil solution without consideration of the Al species are of limited value for precise conclusions of the actual, or for predictions of the potential risk of soil-acidity-induced inhibition of root growth and of nutritional imbalances. The root-induced changes in the rhizosphere and the consequences for Al toxicity and nutrient acquisition by plants deserve more attention. Further it should be considered that roots are not only required for anchoring higher plants in the soil and for nutrient and water uptake. Roots are also important sites for synthesis of phytohormones, cytokinins and abscisic acid in particular, which are transported into the shoots and act either as signals for the water status at the soil-root interface (ABA) or as compounds required for growth and development. Inhibition in root growth may therefore affect shoot growth by means other than water and nutrient supply. (orig./vhe)

  4. Potential of vetiver (vetiveria zizanioides l.) grass in removing selected pahs from diesel contaminated soil

    International Nuclear Information System (INIS)

    Nisa, W.U.; Rashid, A.

    2015-01-01

    Phytoremediation has been renowned as an encouraging technology for the remediation of polycyclic aromatic hydrocarbon (PAH)-contaminated soils, little is known about how plant species behave during the process of PAH phytoremediation. Therefore, the aim of this study was to investigate the effectiveness of vetiver (Vetiveria zizanioides L.) plant in PAH phytoremediation and extraction potential of Vetiveria zizanioides for selected PAHs from the diesel contaminated soil. The field soil samples were spiked with varying concentrations (0.5% and 1%) of diesel and used for pot experiment which was conducted in greenhouse. Vetiver grass was used as experimental plant. Physico-chemical analysis of soil was performed before and after the experiment. Concentration of selected PAHs i.e. phenanthrene, pyrene and benzo(a)pyrene in soil was determined using HPLC. Plant parameters such as root/shoot length and dry mass were compared after harvest. Concentrations of PAHs were also determined in plant material and in soils after harvesting. Result showed that initial concentration of phenanthrene was significantly different from final concentration in treatments in which soil was spiked with diesel. Initial and final concentration of pyrene in soil was also significantly different from each other in two treatments in which soil was spiked with 1% diesel. Pyrene concentration was significantly different in roots and shoots of plants while benzo(a)pyrene concentration in treatments in which soil was spiked with diesel was also significantly different from roots and shoots. Phenanthrene was less extracted by the plant in all the treatments and it was present in higher concentration in soil as compared to plant. Our results indicate that vetiver grass has effectively removed PAHs from soil consequently a significantly higher root and shoot uptake of PAHs was observed than control treatments. Study concludes Vetiveria zizanioides as potentially promising plant specie for the removal

  5. Behavior of Eucalyptus urophylla and Eucalyptus citriodora Seedlings Grown in Soil Contaminated by Arsenate

    Directory of Open Access Journals (Sweden)

    Roseli Freire Melo

    2016-01-01

    Full Text Available ABSTRACT Persistent areas of tailings and deposits from coal and gold mining may present high levels of arsenic (As, mainly in the arsenate form, endangering the environment and human health. The establishment of vegetation cover is a key step to reclaiming these environments. Thus, this study aimed to evaluate the potential of Eucalyptus urophylla and E. citriodora seedlings for use in phytoremediation programs of arsenate-contaminated areas. Soil samples were incubated at increasing rates (0, 50, 100, 200 and 400 mg dm-3 of arsenic (arsenate form, using Na2HAsO4 for 15 days. The seedlings were produced in a substrate (vermiculite + sawdust and were transplanted to the pots with soil three months after seed germination. The values of plant height and diameter were taken during transplanting and 30, 60 and 90 days after transplanting. In the last evaluation, the total leaf area and biomass of shoots and roots were also determined. The values of available As in soil which caused a 50 % dry matter reduction (TS50%, the As translocation index (TI from the roots to the shoot of the plants, and its bioconcentration factor (BF were also calculated. Higher levels of arsenate in the soil significantly reduced the dry matter production of roots and shoots and the height of both species, most notably in E. urophylla plants. The highest levels of As were found in the root, with higher values for E. citriodora (ranging from 253.86 to 400 mg dm-3. The TI and BF were also reduced with As doses, but the values found in E. citriodora were significantly higher than in E. urophylla. E. citriodora plants presented a higher capacity to tolerate As and translocate it to the shoot than E. urophylla. Although these species cannot be considered as hyperaccumulators of As, E. citriodora presented the potential to be used in phytoremediation programs in arsenate-contaminated areas due to the long-term growth period of this species.

  6. Study on remediation for uranium contaminated soils enhanced by chelator using brassica mustard

    International Nuclear Information System (INIS)

    Wan Qinfang; Pan Ning; Jin Yongdong; Xia Chuanqin

    2012-01-01

    Screening of perfect hyperaccumulators is the key to the application of this technology. Through the previous stage study, mustard was found to be good at absorption and accumulation of uranium among 51 species, the plant grows fast with wide adaptability and large biomass. Researches will focus on the following two aspects: 1. Simulating U- contaminated soils was prepared by two different ways to add uranium. (1). UO 2 (NO 3 ) 2 . 6H 2 O solution was sprayed into soil when the plant was grown in the soil; (2). Above U-contaminated soils after planting and placed for a year. Study on whether the way of adding uranium can effect mustard accumulate uranium. Results found: in the first Phytoremediation, U-contaminated concentration at 100 mg/kg, U concentration in shoots reaches 1103.42 mg/kg, roots reach 1909.49 mg/kg, annual removal rate is 7.81%; in the second Phytoremediation, U-contaminated concentration at 100 mg/kg, U concentration in shoots reach 295.83 mg/kg, roots reach 268.42 mg/kg, annual removal rate is 2.52%. Led to the difference between the twice remediation is the speciation of uranium m soils has changed, respectively, Tessier-five step continuous extraction method for determination of uranium speciation in soils and found available uranium (exchangeable uranium, uranium carbonate) in the soil of the first phytoremediation was 52% higher than the second phytoremediation. 2. Study on chelators (Citric acids, Malic acids) and soil amendments (Organic fertilizer, microbe fertilizer. Humic acid organic fertilizer, Urea) whether effect mustard accumulate uranium, found organic fertilizer can reduce shoots accumulate uranium, Citric acid and microbe fertilizer increase shoots enrichment of uranium. (authors)

  7. Phytoremediation of Lead and Cadmium Contaminated Soils using Sunflower Plant

    Directory of Open Access Journals (Sweden)

    Nasser Sewalem

    2014-03-01

    Full Text Available Phytremediation has emerged as a practical approach to clean up metal-polluted soils. In this study the role of sunflower (Helianthus annuus L. plants as a potential phytoremediator to soils contaminated with cadmium (Cd and lead (Pb was investigated. Our results showed that the effect of Cd was stronger on the growth of the roots, while the effect of Pb was stronger on the shoots of sunflower seedlings. At the physiological level, Cd treatment was found to induce low levels of lipid peroxidation and membrane leakage with less affected photosynthesis in the leaves of the treated sunflower seedlings compared to the effects of Pb. The results presented here showed that a high amount of the total absorbed Cd (88.84% was accumulated in roots, while a high amount of the total absorbed Pb (71.39 was tranlocated to shoots of sunflower seedlings. Similar trends of Cd and Pb allocation between roots and shoots at the yield stage were recorded. We suggest here that sunflower plants may remediate Cd contaminated soils through phytostabilization, while may remediate Pb contaminated soils through phytoextraction. Finaly, the trace amounts of Cd and Pb that were accumulated in seeds recommends sunflower plants to be used safely and economically for cleaning up soils contaminated with Cd and/or Pb.

  8. Phytoremediation of anthracene- and fluoranthene contaminated soil by Luffa acutangula

    Directory of Open Access Journals (Sweden)

    Khanitta Somtrakoon

    2014-09-01

    Full Text Available Phytoremediation of soil contaminated with anthracene and fluoranthene, either alone or together, by ridge gourd (Luffa acutangula was investigated through laboratory pot experiments in a greenhouse for 45 days. The i nitial concentration of anthracene or fluoranthene was 100 mg kg -1 when each was spiked alone. When spiked together, the initial concentration of each hydrocarbon was 50 mg kg -1 . The ridge gourd grew normally in anthracene-contaminated soil based on assessment of shoot growth at the end of the experiment. Fluoranthene spiked either alone or together with anthracene was toxic to the plant as shown by significantly reduced shoot and root growth, especiall y on day 45 after transplantation. Planting of ridge gourd was more effective in decreasing the amount of anthracene and fluoranthene from soil than un-planted control during the 45-day experiment. Only 0.5-1.8% and 3.1-14.1% of anthracene and fluoranthene respectively were detected in planted soil on day 45. In contrast, 27.7-48.2% and 46.9-73.8% of anthracene and fluoranthene respectively, spiked alone or together, remained in the control un-planted soil during the same period. The two aromatic hydrocarbons were neither detected in the shoot nor root tissue of the ridge gourd, which suggests that phytostimulation may be the most likely mechanism by which these hydrocarbons were removed from soil.

  9. Date of shoot collection, genotype, and original shoot position affect early rooting of dormant hardwood cuttings of Populus

    Science.gov (United States)

    R. S., Jr. Zalesny; A.H. Wiese

    2006-01-01

    Identifying superior combinations among date of dormant- season shoot collection, genotype, and original shoot position can increase the rooting potential of Populus cuttings. Thus, the objectives of our study were to: 1) evaluate variation among clones in early rooting from hardwood cuttings processed every three weeks from shoots collected...

  10. Effects of soil treatment with abattoir effluent on morphological and ...

    African Journals Online (AJOL)

    The effects of abattoir wastewater treated soil on morphological and biochemical profiles of cowpea seedlings (Vigna unguiculata) grown in gasoline polluted soil was studied. Percentage germination, shoot length, root length and leaf area of cowpea seedlings grown in gasoline treated soil decreased significantly (P ...

  11. Lead Accumulation by Tall Fescue (Festuca arundinacea Schreb. Grown on a Lead-Contaminated Soil

    Directory of Open Access Journals (Sweden)

    D. Gilliard

    2005-08-01

    Full Text Available Phytoextraction is gaining acceptance as a cost-effective and environmentally friendly phytoremediation strategy for reducing toxic metal levels from contaminated soils. Cognizant of the potential of this phytoremediation technique as an alternative to expensive engineering-based remediation technologies, experiments were conducted to evaluate the suitability of some plants as phytoextraction species. From one of our preliminary studies, we found that tall fescue (Festuca arundinacea Schreb. cv. Spirit can tolerate and accumulate significant amounts of lead (Pb in its shoots when grown in Pb-amended sand. To further evaluate the suitability of tall fescue as one of the potential crop rotation species for phytoextraction, a study was conducted to determine whether the addition of ethylenediaminetetraacetic acid (EDTA alone or in combination with acetic acid can further enhance the shoot uptake of Pb. Seeds were planted in 3.8 L plastic pots containing top soil, peat, and sand (4:2:1, v:v:v spiked with various levels (0,1000, 2000 mg Pb/kg dry soil of lead. At six weeks after planting, aqueous solutions (0, 5 mmol/kg dry soil of EDTA and acetic acid (5 mmol/kg dry soil were applied to the root zone, and all plants were harvested a week later. Results revealed that tall fescue was relatively tolerant to moderate levels of Pb as shown by non-significant differences in root and shoot biomass among treatments. An exception to this trend however, was the slight reduction in root and shoot biomass of plants exposed to the highest Pb level in combination with the two chelates. Root Pb concentration increased with increasing level of soil-applied Pb. Further increases in root Pb concentrations were attributed to chelate amendments. Translocation index, which is a measure of the partitioning of the metal to the shoots, was significantly enhanced with chelate addition especially when both EDTA and acetic acid were used. Chelate-induced increases in

  12. Tungsten Speciation in Firing Range Soils

    Science.gov (United States)

    2011-01-01

    satisfactorily, such as: which tungsten mineral phase is present in soil and to what extent is adsorption important in regu- lating soil solution concentrations... soil solution rather than discrete mineral phases. Information provided in this report will assist the following organizations in future decision...the soil solution ERDC TR-11-1 43 must affect tungsten speciation in other ways. The precipitation of soil minerals also would limit tungsten

  13. Optoelectronics applications in multimedia shooting training systems: SPARTAN

    Science.gov (United States)

    Glogowski, Tomasz; Hlosta, Pawel; Stepniak, Slawomir; Swiderski, Waldemar

    2017-10-01

    Multimedia shooting training systems are increasingly being used in the training of security staff and uniformed services. An advanced practicing-training system SPARTAN for simulation of small arms shooting has been designed and manufactured by Autocomp Management Ltd. and Military Institute of Armament Technology for the Polish Ministry of National Defence. SPARTAN is a stationary device designed to teach, monitor and evaluate the targeting of small arms and to prepare soldiers for: • firing the live ammunition at open ranges for combat targets and silhouettes • detection, classification and engagement of real targets upon different terrains, weather conditions and periods during the day • team work as a squad during the mission by using different types of arms • suitable reactions in untypical scenarios. Placed in any room the training set consists of: • the projection system that generates realistic 3D imaging of the battlefield (such as combat shooting range) in high-resolution • system that tracks weapons aiming points • sound system which delivers realistic mapping of acoustic surroundings • operator station with which the training is conducted and controlled • central processing unit based on PC computers equipped with specialist software realizing individual system functions • units of smart weapons equipped with radio communication modules, injection laser diodes and pneumatic reloading system. The system make possible training by firing in dynamic scenarios, using combat weapons and live ammunition against visible targets moving on a screen. The use of infrared camera for detecting the position of impact of a projectile.

  14. Risk assessment of potentially toxic elements in agricultural soils and maize tissues from selected districts in Tanzania

    International Nuclear Information System (INIS)

    Marwa, Ernest M.M.; Meharg, Andrew A.; Rice, Clive M.

    2012-01-01

    A field survey was conducted to investigate the contamination of potentially toxic elements (PTEs) arsenic (As), lead (Pb), chromium (Cr), and nickel (Ni) in Tanzanian agricultural soils and to evaluate their uptake and translocation in maize as proxy to the safety of maize used for human and animal consumption. Soils and maize tissues were sampled from 40 farms in Tanzania and analyzed using inductively coupled plasma-mass spectrometry in the United Kingdom. The results showed high levels of PTEs in both soils and maize tissues above the recommended limits. Nickel levels of up to 34.4 and 56.9 mg kg −1 respectively were found in some maize shoots and grains from several districts. Also, high Pb levels >0.2 mg kg −1 were found in some grains. The grains and shoots with high levels of Ni and Pb are unfit for human and animal consumption. Concentrations of individual elements in maize tissues and soils did not correlate and showed differences in uptake and translocation. However, Ni showed a more efficient transfer from soils to shoots than As, Pb and Cr. Transfer of Cr and Ni from shoots to grains was higher than other elements, implying that whatever amount is assimilated in maize shoots is efficiently mobilized and transferred to grains. Thus, the study recommended to the public to stop consuming and feeding their animals maize with high levels of PTEs for their safety. - Highlights: ► High Ni and Pb levels above the allowable limits were found in maize grains. ► Also maize shoots unfit for animal use were found with high Ni concentrations. ► Mining activities were among the sources of soil contamination. ► The public advised to stop consuming maize with potentially toxic elements.

  15. Investigation of Sensitivity of Some Pulses and Agronomic Crops to Soil Residue of Idosulfuron-mesosulfurun Herbicide

    Directory of Open Access Journals (Sweden)

    E. Izadi-Darbandi

    2013-03-01

    Full Text Available To study the sensitivity of chick pea, bean, lentil, rapeseed, sugarbeet and tomato to soil residual concentration of Idosulfuron-mesosulfurun herbicide, an experiment was carried out under controlled conditions at the College of Agriculture, Ferdowsi University of Mashhad, Iran, in 2010. The studied factors were the 6 mentioned crops, and 7 levels of soil residual concentration of Idosulfuron-mesosulfurun herbicide (0, 0.0015, 0.0037, 0.0079, 0.015, 0.031 and 0.047 mg per kg of soil. The factorial experiment was carried out as a completely randomized design with three replications. Crops' emergence percentage was determined one week after their emergence. Plants' survival percentage and shoot and root biomass production were measured 30 days after their emergence. Results showed that all mentioned characteristics decreased significantly (P<0.01 in the presence of soil residue of the herbicide. Increasing Idosulfuron-mesosulfurun residual concentration in soil decreased emergence and shoot and root biomass production. Bean had the lowest shoot (44% and root (66.78% biomass loss and tomato had the highest shoot (96.38% and root (89.64% biomass loss. Based on ED50 index, pea (0.0079 mg/kg soil was the most tolerant and tomato (0.0003 mg/kg soil was the most susceptible crop to soil residues of Idosulfuron-mesosulfurun, and other crops ranked in between as: tomato< sugarbeet< rapeseed< lentil< bean< pea. In general, these results showed that soil residue of Idosulfuron-mesosulfurun can injure rotation crops and it is important to consider their sensitivity in rotation programming.

  16. Long-term Cu stabilization and biomass yields of Giant reed and poplar after adding a biochar, alone or with iron grit, into a contaminated soil from a wood preservation site.

    Science.gov (United States)

    Oustriere, Nadège; Marchand, Lilian; Lottier, Nathalie; Motelica, Mikael; Mench, Michel

    2017-02-01

    A 2-year pot experiment was carried out to examine the aging effect of biochar (B), alone or combined with iron grit (Z), on Cu stabilization and plant growth in a contaminated soil (964mg Cu kg -1 ) from a wood preservation site. The experiment consisted in 3 soil treatments, either planted with Arundo donax L. (Ad) or Populus nigra L. (Pn): (1) untreated Cu-contaminated soil (Ad, Pn); (2) Unt+1% (w/w) B (AdB, PnB), and (3) Unt+1% B+1% Z (AdBZ, PnBZ). After 22months, the soil pore water (SPW) was sampled and roots and shoots were harvested. The SPW compositions at 3 and 22months were compared, showing that the SPW Cu 2+ concentration increased again in the PnB and PnBZ soils. Cultivation of A. donax enhanced the dissolved organic matter concentration in the SPW, which decreased its Cu 2+ concentration but promoted its total Cu concentration in the Ad and AdB soils. Adding Z with B reduced both SPW Cu 2+ and Cu concentrations in the pots cultivated by A. donax and P. nigra as compared to B alone. The B and BZ treatments did not enhance root and shoot yields of both plant species as compared to the Unt soil but their shoot Cu concentrations were in the range of common values. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Training visual control in wheelchair basketball shooting

    NARCIS (Netherlands)

    Oudejans, R.R.D.; Heubers, S.; Ruitenbeek, J-R.J.A.C.; Janssen, T.W.J.

    2012-01-01

    We examined the effects of visual control training on expert wheelchair basketball shooting, a skill more difficult than in regular basketball, as players shoot from a seated position to the same rim height. The training consisted of shooting with a visual constraint that forced participants to use

  18. Long-range alpha detection applied to soil surface monitoring

    International Nuclear Information System (INIS)

    Caress, R.W.; Allander, K.S.; Bounds, J.A.; Catlett, M.M.; MacArthur, D.W.; Rutherford, D.A.

    1992-01-01

    The long-range alpha detection (LRAD) technique depends on the detection of ion pairs generated by alpha particles losing energy in air rather than on detection of the alpha particles themselves. Typical alpha particles generated by uranium will travel less than 3 cm in air. In contrast, the ions have been successfully detected many inches or feet away from the contamination. Since LRAD detection systems are sensitive to all ions simultaneously, large LRAD soil surface monitors (SSMS) can be used to collect all of the ions from a large sample. The LRAD SSMs are designed around the fan-less LRAD detector. In this case a five-sided box with an open bottom is placed on the soil surface. Ions generated by alpha decays on the soil surface are collected on a charged copper plate within the box. These ions create a small current from the plate to ground which is monitored with a sensitive electrometer. The current measured is proportional to the number of ions in the box, which is, in turn, proportional to the amount of alpha contamination on the surface of the soil. This report includes the design and construction of a 1-m by 1-m SSM as well as the results of a study at Fernald, OH, as part of the Uranium in Soils Integrated Demonstration

  19. Absorption, distribution and utilization of soil-applied 10B in apple trees

    International Nuclear Information System (INIS)

    Peng Futian; He Chengshun; Gu Manru

    1998-01-01

    10 B utilization rate was 7.0% and 10 B distribution rate in roots, trunks and newly emerged organs of pot cultured apple tree (cv. 'liao fu'/Malus ptunifolia Borkh.) was 24.4%, 46.6% and 29.0%, respectively, in one month after soil-application of 10 B during shoot rapid growth period. As the aerial newly emerged organs were concerned, Bdff% in long shoots and its leaves were higher than that in other shoots and leaves, suggesting that long shoots and its leaves had stronger ability of up taking 10 B. At beginning of boron application, total boron amount and Bdff% in leaves increased fast, but 10 B accumulating speed in shoot, particularly in its cortex, was higher than that in leaves in the later growing season, indicating that distribution center changed with growing period. The reserved boron in root and trunk played a mediative role in boron supply to newly emerged organs, a part of reserved mobile boron could transport to newly emerged organs when roots could not absorb any boron. With soil-applied 10 B of 2μg·g -1 in autumn, Bdff% in soil was found less than 5% in the spring of the third year, but Bdff% in newly emerged organs was still 20%∼30%, which suggested that a part of reserved 10 B could be reused

  20. Effects of mulching tolerant plant straw on soil surface on growth and cadmium accumulation of Galinsoga parviflora.

    Directory of Open Access Journals (Sweden)

    Lijin Lin

    Full Text Available Pot and field experiments were conducted to study the effects of mulching with straw of cadmium (Cd tolerant plants (Ranunculus sieboldii, Mazus japonicus, Clinopodium confine and Plantago asiatica on growth and Cd accumulation of Galinsoga parviflora in Cd-contaminated soil. In the pot experiment, mulching with M. japonicus straw increased the root biomass, stem biomass, leaf biomass, shoot biomass, plant height and activities of antioxidant enzymes (superoxide dismutase, peroxidase and catalase of G. parviflora compared with the control, whereas mulching with straws of R. sieboldii, C. confine and P. asiatica decreased these parameters. Straws of the four Cd-tolerant plants increased the Cd content in roots of G. parviflora compared with the control. However, only straws of M. japonicus and P. asiatica increased the Cd content in shoots of G. parviflora, reduced the soil pH, and increased the soil exchangeable Cd concentration. Straw of M. japonicus increased the amount of Cd extraction in stems, leaves and shoots of G. parviflora by 21.11%, 29.43% and 24.22%, respectively, compared with the control, whereas straws of the other three Cd-tolerant plants decreased these parameters. In the field experiment, the M. japonicus straw also increased shoot biomass, Cd content in shoots, and amount of Cd extraction in shoots of G. parviflora compared with the control. Therefore, straw of M. japonicus can be used to improve the Cd extraction ability of G. parviflora from Cd-contaminated soil.

  1. Influence of substrate and mycorrhizal fungus on the root and shoot architecture of coffee-shading walnut (Cordia alliodora [Ruiz et Pav.] Oken

    Directory of Open Access Journals (Sweden)

    Rodriguez Pérez Loyla

    2012-04-01

    Full Text Available

    Cordia alliodora (coffee-shading walnut is a species of economic importance to Colombia because of its multiple uses for farmers and for reforestation as a timber and industrial resources, mainly in the central coffee region of the country. The aim of this research was to study parameters of C. alliodora shoot and root system architecture over the first year of development. Plants were established in Pacho municipality (Cundinamarca at an 2,150 m a.s.l. A split plot design with a randomized complete block and three replicates was applied. Within the main plot, we evaluated the substrates (soil, husk and compost 2:1:1; soil and husk 3:2; soil and husk 3:1, and withing the subplot, the mycorrhizal fungus (without fungus, Kuklospora colombiana, Glomus manihotis and Acaulospora lacunosa. Substrate type affected C. alliodora root and shoot architectural parameters. Plants transplanted into soil, husk and compost 2:1:1 had the best responses in architectural parameters: diameter of the base of the root (7.82 mm, number of secondary roots (48.4, root dry weight (5.38 g, number of leaves (47.33, dry weight of shoots (7.71 g, shoot length (72.64 g and leaf dry weight (6.28 g at 384 days after transplant. Since no fertilizer was applied to coffee-shading walnut plants, we conclude that the mycorrhizal fungi facilitated a better use and development of mineral elements present in the substrates.

  2. Compactação do solo e manejo da água. I: efeitos sobre a absorção de N, P, K, massa seca de raízes e parte aérea de plantas de arroz Soil compaction and water management. I: effects upon uptake of N, P, K, root and shoot dry matter of rice plants

    Directory of Open Access Journals (Sweden)

    Roberto Dantas de Medeiros

    2005-10-01

    Full Text Available Com o presente trabalho objetivou-se avaliar os efeitos de seis níveis de compactação, associados a diferentes manejos de água, sobre a absorção de nitrogênio (N, fósforo (P e potássio (K, o desenvolvimento do sistema radicular e parte aérea de plantas de arroz. O experimento foi conduzido no período de setembro de 2002 a janeiro de 2003 em casa- de-vegetação da UFLA, em Lavras-MG. Testou-se seis níveis de compactação do solo: 0%, 16%, 32%, 48%, 64% e 80% da amplitude de variação da densidade do solo (0,25 kg dm-3, combinado com três teores de água no solo: solo saturado, irrigado quando eram consumidos de 25% a 30% e de 50% a 60% da água disponível, respectivamente. O manejo com maior disponibilidade de água no solo favoreceu as médias dos teores de P e de K na parte aérea das plantas, a produção de massa seca da raiz, o número de perfilhos por vaso e a massa seca da parte aérea das plantas de arroz, independentemente dos níveis de compactação do solo. Por outro lado, a compactação do solo diminuiu as médias de todas características avaliadas, independentemente do manejo de água. Entretanto, o manejo de água teve efeito mais limitante sobre a absorção dos nutrientes e a produção de massa seca da parte aérea das plantas do que a compactação do solo.The present work had as objective to evaluate the effects six compaction levels, associated with different water managements upon uptake of nitrogen (N, phosphorus (P and potassium (K, the development of root and shoot of rice plants. The experiment was conducted during the period of September 2002 to January 2003 in a greenhouse at UFLA university, in Lavras- MG. Six compaction levels were tested: 0%, 16%, 32%, 48%, 64% and 80% in a range of variation of soil density (0.25 kg dm-3, combined with three soil water contents: saturated soil, irrigated when were consumed from 25% to 30% and from 50% to 60% of available water, respectively. The management with

  3. Soil feedback and pathogen activity in Prunus serotina throughout its native range

    Science.gov (United States)

    Kurt O. Reinhart; Alejandro Royo; Wim H. Van der Putten; Keith Clay

    2005-01-01

    1 Oomycete soil pathogens are known to have a negative effect on Prunus serotina seedling establishment and to promote tree diversity in a deciduous forest in Indiana, USA. Here, we investigate whether negative feedbacks operate widely in its native range in eastern USA. 2 In laboratory experiments, soil sterilization was used to test the...

  4. Rampage shootings: an historical, empirical, and theoretical overview.

    Science.gov (United States)

    Rocque, Michael; Duwe, Grant

    2018-02-01

    Rampage shootings is a relatively new term to describe a phenomenon that has a long history. Rampage shootings are mass shootings (generally defined as involving four or more victims), taking place in a public location, with victims chosen randomly or for symbolic purposes. These shootings are isolated events, meaning they are not connected to another criminal act (such as robbery or terrorism). Research suggests that rampage shootings are not a new phenomenon, but have occurred throughout the US since the early 1900s. There is some evidence of an increase in recent years, but definitional differences across studies and data sources make interpreting trends somewhat tenuous. Theories regarding the perpetration of rampage shootings center on masculinity, mental illness, and contagion effects. Policies aimed at preventing rampage shootings remain somewhat controversial and not well-tested in the literature. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Modeling shoot-tip temperature in the greenhouse environment

    International Nuclear Information System (INIS)

    Faust, J.E.; Heins, R.D.

    1998-01-01

    An energy-balance model is described that predicts vinca (Catharanthus roseus L.) shoot-tip temperature using four environmental measurements: solar radiation and dry bulb, wet bulb, and glazing material temperature. The time and magnitude of the differences between shoot-tip and air temperature were determined in greenhouses maintained at air temperatures of 15, 20, 25, 30, or 35 °C. At night, shoot-tip temperature was always below air temperature. Shoot-tip temperature decreased from 0.5 to 5 °C below air temperature as greenhouse glass temperature decreased from 2 to 15 °C below air temperature. During the photoperiod under low vapor-pressure deficit (VPD) and low air temperature, shoot-tip temperature increased ≈4 °C as solar radiation increased from 0 to 600 W·m -2 . Under high VPD and high air temperature, shoot-tip temperature initially decreased 1 to 2 °C at sunrise, then increased later in the morning as solar radiation increased. The model predicted shoot-tip temperatures within ±1 °C of 81% of the observed 1-hour average shoot-tip temperatures. The model was used to simulate shoot-tip temperatures under different VPD, solar radiation, and air temperatures. Since the rate of leaf and flower development are influenced by the temperature of the meristematic tissues, a model of shoot-tip temperature will be a valuable tool to predict plant development in greenhouses and to control the greenhouse environment based on a plant temperature setpoint. (author)

  6. Author Details

    African Journals Online (AJOL)

    Immobilization of lead in shooting range soil using biochar from spent mushroomsubstrateImmobilization of lead in shooting range soil using biochar from spent mushroomsubstrate. Abstract PDF · Vol 9, No 6S (2017) - Articles Sorption of malachite green (MG) by cassava stem biochar (CSB) kinetic and isotherm studies

  7. Regrowth of Cirsium arvense from intact roots and root fragments at different soil depths

    Directory of Open Access Journals (Sweden)

    Thomsen, Mette Goul

    2014-02-01

    Full Text Available In the present work we measured the shoot rate from intact roots and from root fragments of Cirsium arvense at different digging depths and the number of leaves were used as estimate of minimum regenerative capacity. The experiments were performed on four sites with three or four repetitions of each treatment. On each site plot, the soil was removed down to a given depth within a 1 x 1 m square. All plant parts was excavated from the soil and the soil was either replaced without any root material, or roots of C. arvense was cut into 10 cm long fragments and replaced into the source hole. Shoot number, aboveground biomass and number of leaves were measured. Digging depth and time explained 50% - 60% of the variation in biomass (P<0.001. Replacement of root fragments increased the shoot number in one out of four treatments but did not affect biomass produced compared to production from undisturbed root systems. Number of leaves showed that shoots from all digging depths passed the level of minimum regenerative capacity. We conclude that the intact root system from all depths was able to regenerate within one season and it has a high contribution to the produced biomass compared with root fragments in the upper soil layers.

  8. Shoot regeneration of limau purut (citrus hystrix) using shoot tip: assessment of calcium gluconate and silver nitrate in overcoming premature leaf senescence

    International Nuclear Information System (INIS)

    Eng, W.H.; Aziz, M.A.; Sinniah, U.R.

    2014-01-01

    This study was carried out to establish an optimum In vitro shoot multiplication system using shoot tip explants derived from 7 week-old seedlings of Citrus hystrix. In the first experiment, shoot tips were cultured on Murashige and Skoog (MS) medium supplemented with 0-13.33 mu M 6-benzylaminopurine (BAP) for 8 weeks. Shoot tips cultured on 2.22 mu M BAP produced the highest mean number of shoots (3.42 shoots) but the shoots had low number of leaves (1.14 leaves) due to the occurrence of premature leaf senescence and callus formation. Meanwhile, the medium devoid of BAP produced the lowest mean number of shoots (1.50 shoots) but highest mean number of leaves (5.41 leaves) indicating that BAP was likely responsible for the premature leaf senescence. In order to overcome the occurrence of premature leaf senescence on medium with BAP, a second experiment was carried out whereby shoot tips were cultured on medium containing 2.22 micro M BAP fortified with 2.00, 4.00 and 6.00 mM calcium gluconate (Ca-glu) and a control treatment with 2.22 mu M BAP. The shoot and leaf numbers were increased with the addition of 4.00 and 6.00 mM Ca-glu. The presence of Ca-glu reduced premature leaf senescence and callus formation to some extent. In the third experiment, the addition of silver nitrate (AgNO/sub 3/) at 10-80 micro M in media with 2.22 micro M BAP and 2.22 micro M BAP + 4 mM Ca-glu could totally overcome premature leaf senescence and callus formation. Media supplemented with 2.22 mirco M BAP + 4 mM Ca-glu + 20 micro M AgNOsub 3/ significantly induced among the highest mean number of shoots and highest mean number of leaves per shoot. (author)

  9. Effects of salinity and Cu on total uptake of micronutrient in shoot and root of pistachio cultivars (Pistacia vera L.)

    OpenAIRE

    S. Eskandari; V. Mozaffari

    2013-01-01

    To study the effects of soil Cu and salinity levels on uptake of micronutrients by shoots and roots of pistachio seedlings, a factorial experiment was carried out as completely randomized design with three replications in greenhouse of College of Agriculture, Vali-e-Asr University of Rafsanjan, Iran, in May 2008. Treatments consisted of five salinity levels (0, 800, 1600, 2400 and 3200 mg NaCl per kg soil), four Cu levels (0, 2.5, 5 and 7.5 mg Cu per kg soil) and two pistachio cultivars (Bada...

  10. Competition increases sensitivity of wheat (Triticum aestivum) to biotic plant-soil feedback.

    Science.gov (United States)

    Hol, W H Gera; de Boer, Wietse; ten Hooven, Freddy; van der Putten, Wim H

    2013-01-01

    Plant-soil feedback (PSF) and plant competition play an important role in structuring vegetation composition, but their interaction remains unclear. Recent studies suggest that competing plants could dilute pathogenic effects, whereas the standing view is that competition may increase the sensitivity of the focal plant to PSF. In agro-ecosystems each of these two options would yield contrasting outcomes: reduced versus enhanced effects of weeds on crop biomass production. To test the effect of competition on sensitivity to PSF, we grew Triticum aestivum (Common wheat) with and without competition from a weed community composed of Vicia villosa, Chenopodium album and Myosotis arvensis. Plants were grown in sterilized soil, with or without living field inoculum from 4 farms in the UK. In the conditioning phase, field inocula had both positive and negative effects on T. aestivum shoot biomass, depending on farm. In the feedback phase the differences between shoot biomass in T. aestivum monoculture on non-inoculated and inoculated soils had mostly disappeared. However, T. aestivum plants growing in mixtures in the feedback phase were larger on non-inoculated soil than on inoculated soil. Hence, T. aestivum was more sensitive to competition when the field soil biota was present. This was supported by the statistically significant negative correlation between shoot biomass of weeds and T. aestivum, which was absent on sterilized soil. In conclusion, competition in cereal crop-weed systems appears to increase cereal crop sensitivity to soil biota.

  11. Training Visual Control in Wheelchair Basketball Shooting

    Science.gov (United States)

    Oudejans, Raoul R. D.; Heubers, Sjoerd; Ruitenbeek, Jean-Rene J. A. C.; Janssen, Thomas W. J.

    2012-01-01

    We examined the effects of visual control training on expert wheelchair basketball shooting, a skill more difficult than in regular basketball, as players shoot from a seated position to the same rim height. The training consisted of shooting with a visual constraint that forced participants to use target information as late as possible.…

  12. Radiosensitivity of in vitro Cultured Banana Shoot-Tips

    International Nuclear Information System (INIS)

    Elagamawy, M.R.

    2002-01-01

    Longitudinally dissected shoot apices of Grand Nain, Williams and Maghrabi banana cultivars were exposed to gamma irradiation with Cobalt 60 source at the doses of 0, 20, 40 and 60 Gy and immediately placed into proliferation medium. A number of micropropagation cycles after irradiation were necessary up to M1 V2 to M1 V4 stage to let mutated sectors developing into non-chimeric shoots. Radiosensitivity was evaluated by the rate of shoot proliferation and by the shoot fresh weight increase. Increasing gamma doses caused reduction in survival rates and average number of shoots. Grand Nain exhibited the highest multiplication- rate (3.1). The lower dose (20 Gy) enhanced shoot multiplication ratio specially in Williams and Maghrabi, which however decreased with increased doses. The doses of 20-40 Gy yielded Ld50, with sensible degree of shoot multiplication, which occurred hardly ever beyond 40 Gy. The dose of 60 Gy resulted 80% lethal shoot growth. Linear decrease in fresh weight was observed in post-irradiation recovery, notably in the Maghrabi. In contradictory vulnerable damage was observed in Williams which showed the highest fresh weight value. Shoot proliferation appeared generally on the surface of the corm. Root formation was observed without additional hormone. The roots were dark colored and was decreased with the increased of dosage

  13. Screening of a new cadmium hyperaccumulator, Galinsoga parviflora, from winter farmland weeds using the artificially high soil cadmium concentration method.

    Science.gov (United States)

    Lin, Lijin; Jin, Qian; Liu, Yingjie; Ning, Bo; Liao, Ming'an; Luo, Li

    2014-11-01

    A new method, the artificially high soil cadmium (Cd) concentration method, was used to screen for Cd hyperaccumulators among winter farmland weeds. Galinsoga parviflora was the most promising remedial plant among 5 Cd accumulators or hyperaccumulators. In Cd concentration gradient experiments, as soil Cd concentration increased, root and shoot biomass decreased, and their Cd contents increased. In additional concentration gradient experiments, superoxide dismutase and peroxidase activities increased with soil Cd concentrations up to 75 mg kg(-1) , while expression of their isoenzymes strengthened. Catalase (CAT) activity declined and CAT isoenzyme expression weakened at soil Cd concentrations less than 50 mg kg(-1) . The maxima of Cd contents in shoots and roots were 137.63 mg kg(-1) and 105.70 mg kg(-1) , respectively, at 100 mg kg(-1) Cd in soil. The root and shoot bioconcentration factors exceeded 1.0, as did the translocation factor. In a field experiment, total extraction of Cd by shoots was 1.35 mg m(-2) to 1.43 mg m(-2) at soil Cd levels of 2.04 mg kg(-1) to 2.89 mg kg(-1) . Therefore, the artificially high soil Cd concentration method was effective for screening Cd hyperaccumulators. Galinsoga parviflora is a Cd hyperaccumulator that could be used to efficiently remediate Cd-contaminated farmland soil. © 2014 SETAC.

  14. Assessment of soil-gas, seep, and soil contamination at the North Range Road Landfill, Fort Gordon, Georgia, 2008-2009

    Science.gov (United States)

    Landmeyer, James E.; Falls, W. Fred; Ratliff, W. Hagan; Wellborn, John B.

    2011-01-01

    Soil gas, seeps, and soil were assessed for contaminants at the North Range Road Landfill at Fort Gordon, Georgia, from October 2008 to September 2009. The assessment included delineating organic contaminants present in soil-gas samples beneath the area estimated to be the landfill and in water samples collected from three seeps at the base of the landfill. Inorganic contaminants were determined in three seep samples and in soil samples. This assessment was conducted to provide environmental contamination data to Fort Gordon pursuant to requirements for the Resource Conservation and Recovery Act Part B Hazardous Waste Permit process.

  15. Root-zone temperatures affect phenology of bud break, flower cluster development, shoot extension growth and gas exchange of 'Braeburn' (Malus domestica) apple trees.

    Science.gov (United States)

    Greer, Dennis H; Wünsche, Jens N; Norling, Cara L; Wiggins, Harry N

    2006-01-01

    We investigated the effects of root-zone temperature on bud break, flowering, shoot growth and gas exchange of potted mature apple (Malus domestica (Borkh.)) trees with undisturbed roots. Soil respiration was also determined. Potted 'Braeburn' apple trees on M.9 rootstock were grown for 70 days in a constant day/night temperature regime (25/18 degrees C) and one of three constant root-zone temperatures (7, 15 and 25 degrees C). Both the proportion and timing of bud break were significantly enhanced as root-zone temperature increased. Rate of floral cluster opening was also markedly increased with increasing root-zone temperature. Shoot length increased but shoot girth growth declined as root-zone temperatures increased. Soil respiration and leaf photosynthesis generally increased as root-zone temperatures increased. Results indicate that apple trees growing in regions where root zone temperatures are or = 15 degrees C. The effect of root-zone temperature on shoot performance may be mediated through the mobilization of root reserves, although the role of phytohormones cannot be discounted. Variation in leaf photosynthesis across the temperature treatments was inadequately explained by stomatal conductance. Given that root growth increases with increasing temperature, changes in sink activity induced by the root-zone temperature treatments provide a possible explanation for the non-stomatal effect on photosynthesis. Irrespective of underlying mechanisms, root-zone temperatures influence bud break and flowering in apple trees.

  16. Comparative analysis of tannery-effluent contaminated soil and mixed culture bacterial inoculation on helianthus annuus L. growth

    International Nuclear Information System (INIS)

    Yasin, M.; Faisal, M.

    2012-01-01

    Here we reported the effect of four strains Bacillus pumilus-CrK08, Cellulosimicrobium cellulans-CrK16, Exiguobacterium-CrK19 and Bacillus cereus-CrK20 and tannery contaminated soil on Helianthus annuus L. var Hysun-33 growth parameters. Plants growing in tannery effluent contaminated soil have shown slowed leaf growth, reduced shoot length, burning of leaf margins and tips compared to plants growing in normal garden soil. The inoculated plants had shown overall increase in root length (15%), shoot length (33%) and fresh weight shoot (135%) compared to un-inoculated plants growing in stress conditions. Plants growing in tannery contaminated soil have shown increase in soluble proteins contents (9%), acid phosphatase activity (200%), peroxidase activity (203%) and decrease in chlorophyll a (39%), chlorophyll b (23%) and carotenoids contents (28%) compare to plants growing in normal control soil. Inoculated plants grown in contaminated soil have shown an increased in peroxidase activity, soluble proteins contents, acid phosphatase activity, chlorophyll a, b and carotenoid contents compare to respective un-inoculated plants. (author)

  17. Auxin-cytokinin synergism in vitro for producing genetically stable plants of Ruta graveolens using shoot tip meristems

    Directory of Open Access Journals (Sweden)

    Mohammad Faisal

    2018-02-01

    Full Text Available An efficient micropropagation protocol was developed for Ruta graveolens Linn. using shoot tip meristems derived from a 4-month-old field grown plant. In vitro shoot regeneration and proliferation was accomplished on Murashige and Skoogs (MS semi-solid medium in addition to different doses of cytokinins viz.6- benzyl adenine (BA, Kinetin (Kn or 2-isopetynyl adenine (2iP, singly or in combination with auxins viz. indole-3-acetic acid (IAA, indole-3-butyric acid (IBA or α-naphthalene acetic acid (NAA. Highest regeneration frequency (27.6% was obtained on (MS medium composed of BA (10 µM with maximum number (9.4 of shoots and 4.3 cm shoot length after 4 weeks of incubation. Among various combinations tried best regeneration frequency (71% of multiple shoot formation with highest number (12.6 of shoots per shoot tip explants were achieved in MS medium augmented with a combination BA (10.0 µM and NAA (2.5 µM after 4 weeks of incubation. The optimum frequency (97% of rhizogenesis was achieved on half-strength MS medium having 0.5 µM IBA after 4 weeks of incubation. Tissue culture raised plantlets with 5–7 fully opened leaves with healthy root system were successfully acclimatized off in Soilrite™ with 80% survival rate followed by transportation to normal soil under natural light. Genetic stability among in vitro raised progeny was evaluated by ISSR and RAPD markers. The entire banding pattern revealed from in vitro regenerated plants was monomorphic to the donor. The present protocol provides an alternative option for commercial propagation and fruitful setting up of genetically uniform progeny for sustainable utilization and germplasm preservation.

  18. Quantifying Cr(VI) Production and Export from Serpentine Soil of the California Coast Range.

    Science.gov (United States)

    McClain, Cynthia N; Fendorf, Scott; Webb, Samuel M; Maher, Kate

    2017-01-03

    Hexavalent chromium (Cr(VI)) is generated in serpentine soils and exported to surface and groundwaters at levels above health-based drinking water standards. Although Cr(VI) concentrations are elevated in serpentine soil pore water, few studies have reported field evidence documenting Cr(VI) production rates and fluxes that govern Cr(VI) transport from soil to water sources. We report Cr speciation (i) in four serpentine soil depth profiles derived from the California Coast Range serpentinite belt and (ii) in local surface waters. Within soils, we detected Cr(VI) in the same horizons where Cr(III)-minerals are colocated with biogenic Mn(III/IV)-oxides, suggesting Cr(VI) generation through oxidation by Mn-oxides. Water-extractable Cr(VI) concentrations increase with depth constituting a 7.8 to 12 kg/km 2 reservoir of Cr(VI) in soil. Here, Cr(VI) is produced at a rate of 0.3 to 4.8 kg Cr(VI)/km 2 /yr and subsequently flushed from soil during water infiltration, exporting 0.01 to 3.9 kg Cr(VI)/km 2 /yr at concentrations ranging from 25 to 172 μg/L. Although soil-derived Cr(VI) is leached from soil at concentrations exceeding 10 μg/L, due to reduction and dilution during transport to streams, Cr(VI) levels measured in local surface waters largely remain below California's drinking water limit.

  19. Uptake of heavy metals by plants from airborne deposition and polluted soils

    Directory of Open Access Journals (Sweden)

    T. YLÄRANTA

    2008-12-01

    Full Text Available The concentrations of sulphur, zinc, copper, lead and cadmium in spring wheat grain and straw, Italian rye grass, timothy and lettuce were studied in a three-year field experiment conducted in southern Finland near a copper-nickel smelter and at nonpolluted control sites. A pot experiment with copper- and nickel-contaminated soils and with a nonpolluted soil as the control was conducted to determine the copper and nickel concentrations in soils phytotoxic for plants. Forty, 200 or 1000 mg of copper or nickel as cloride was added to 2 litres of soil. The nickel and copper concentrations in the shoots of oats were measured. The zinc, copper, lead, cadmium and nickel concentrations varied between different plant species and also between experimental years. Near the smelter, the uptake of nickel by different plant species was very effective, as was copper uptake by lettuce, timothy and Italian rye grass. The same applied to the zinc and cadmium uptake of plants grown on plots. Nickel, cadmium and copper were easily accumulated by plants from air deposition. In the pot experiment, high nickel concentrations in soil were more phytotoxic for oats than were high copper concentrations. In acidic soil, nickel and copper concentrations lower than 20 and 100 mg/kg of soil, respectively, decreased the dry matter yield of oats shoots. Liming clearly decreased copper and nickel phytotoxity. In the most highly contaminated soil, the addition of Cu 20 mg/kg of soil decreased the yield of oats shoots.;

  20. A School Shooting Plot Foiled

    Science.gov (United States)

    Swezey, James A.; Thorp, Kimberly A.

    2010-01-01

    Dinkes, Cataldi, and Lin-Kelly (2007) claims that 78% of public schools reported one or more violent incidents during the 2005/2006 school year. School shootings are a rare but real threat on school campuses. Shootings at private schools are even less frequent with only a few recorded examples in the United States. This case study examines how a…

  1. Lithosequence of soils and associated vegetation on subalpine range of the Wasatch Plateau, Utah.

    Science.gov (United States)

    James O. Klemmedson; Arthur R. Tiedemann

    1998-01-01

    On degraded subalpine range in Utah, the authors examined the role of soil and parent material nutrients and organic carbon (Corg) in the development of soil and plants on a transect across six strata that formed visible concentric alternating bands of high and low productivity. Relations for soil and parent material phosphorus (P) and sulfur (S) were of particular...

  2. Infection of non-host model plant species with the narrow-host-range Cacao swollen shoot virus.

    Science.gov (United States)

    Friscina, Arianna; Chiappetta, Laura; Jacquemond, Mireille; Tepfer, Mark

    2017-02-01

    Cacao swollen shoot virus (CSSV) is a major pathogen of cacao (Theobroma cacao) in Africa, and long-standing efforts to limit its spread by the culling of infected trees have had very limited success. CSSV is a particularly difficult virus to study, as it has a very narrow host range, limited to several tropical tree species. Furthermore, the virus is not mechanically transmissible, and its insect vector can only be used with difficulty. Thus, the only efficient means to infect cacao plants that have been experimentally described so far are by particle bombardment or the agroinoculation of cacao plants with an infectious clone. We have genetically transformed three non-host species with an infectious form of the CSSV genome: two experimental hosts widely used in plant virology (Nicotiana tabacum and N. benthamiana) and the model species Arabidopsis thaliana. In transformed plants of all three species, the CSSV genome was able to replicate, and, in tobacco, CSSV particles could be observed by immunosorbent electron microscopy, demonstrating that the complete virus cycle could be completed in a non-host plant. These results will greatly facilitate the preliminary testing of CSSV control strategies using plants that are easy to raise and to transform genetically. © 2016 BSPP AND JOHN WILEY & SONS LTD.

  3. Concentration- and Time-Dependent Effects of Isothiocyanates Produced from Brassicaceae Shoot Tissues on the Pea Root Rot Pathogen Aphanomyces euteiches

    NARCIS (Netherlands)

    Hossain, S.; Bergkvist, G.; Berglund, K.; Glinwood, R.; Kabouw, P.; Martensson, A.; Persson, P.

    2014-01-01

    Isothiocyanates (ITCs) hydrolyzed from glucosinolates (GSLs) in Brassicaceae tissue are toxic to soil organisms. In this study, the effect of aliphatic and aromatic ITCs from hydrated dry Brassicaceae shoot tissues on the mycelium and oospores of the pea root rot pathogen Aphanomyces euteiches was

  4. Effect of tillage on soil physical properties, growth and yield of ...

    African Journals Online (AJOL)

    ... ploughing plus harrowing plus bedding (PHB), on soil physical properties, growth and shoot yield of large-green leafy amaranth (Amaranth sp.). Soil moisture retention and infiltration rates were also measured in two cropping seasons. Soil moisture retention did not reflect any significant differences in the first and second ...

  5. Phytoremediation of Soil Trace Elements

    Science.gov (United States)

    Phytoremediation includes several distinct approaches to using plants to achieve soil remediation goals. Phytoextraction uses rare hyperaccumulator plants to accumulate in their shoots enough metals per year to achieve decontamination goals. Phytomining uses hyperaccumulators and biomass burn to pro...

  6. Phytoremediation modelling - phytoextraction of 137Cs, 133Ba, and 90Sr from liquid media and artificially contaminated soil

    International Nuclear Information System (INIS)

    Smrcek, S.; Masnerova, G.

    2002-01-01

    The phytoremediation model based on experiments with plants cultivated in vitro in media supplemented with radionuclide salts was investigated. The plant species Brassica napus, Sinapis alba, Helianthus annuus, Zea mays and Pisum sativum were cultivated on the Murashige-Skoog basal salt mixture enriched with salts of 137 Cs, 133 Ba, and 90 Sr in aseptic conditions. The time-dependent radioactivity decrease in the medium was determined using LSC, and the phytoextraction curves were plotted. Radioactivity in the plant roots and shoots was measured and the efficiency of phytoextraction and the distribution between the roots and shoots as a measure of radionuclide transport in the plant tissues were calculated for each of the plants used. Cultivation experiments were also performed on artificially contaminated soil. Seeds of the plants were placed into contaminated soil and cultivated for 2 months in conditions similar to those of the in vitro experiments. The extracted radioactivity and distribution between roots and shoots were determined. The in vitro experiments simulated extraction of the radionuclide salt from solution analogously to real extraction from the soil solution, while the processes occurring in the rhizosphere were eliminated. The phytoextraction efficiency in terms of the percentage of the starting radioactivity ranged from 12 to 31 % for 90 Sr, 8 to 24% for 137 Cs, and 12 to 17 % for 133 Ba in a cultivation cycle. The root/shoot radioactivity ratios demonstrate that the plant species used may be suitable for real phytoremediation. The experiments in which the plants were cultivated from seeds in artificial contaminated substrate showed that the ability of roots to extract radionuclide salts from their environment remains unchanged. The relative efficiency values were lower than for the extraction from solutions (3 to 11.5 % for 90 Sr, 1.5 to 4 % for 137 Cs, and 1 to 6.2 %, for 133 Ba), but in this process, the equilibrium between the soil particles

  7. Anti-transpirant activity in xylem sap from flooded tomato (Lycopersicon esculentum Mill.) plants is not due to pH-mediated redistributions of root- or shoot-sourced ABA.

    Science.gov (United States)

    Else, Mark A; Taylor, June M; Atkinson, Christopher J

    2006-01-01

    In flooded soils, the rapid effects of decreasing oxygen availability on root metabolic activity are likely to generate many potential chemical signals that may impact on stomatal apertures. Detached leaf transpiration tests showed that filtered xylem sap, collected at realistic flow rates from plants flooded for 2 h and 4 h, contained one or more factors that reduced stomatal apertures. The closure could not be attributed to increased root output of the glucose ester of abscisic acid (ABA-GE), since concentrations and deliveries of ABA conjugates were unaffected by soil flooding. Although xylem sap collected from the shoot base of detopped flooded plants became more alkaline within 2 h of flooding, this rapid pH change of 0.5 units did not alter partitioning of root-sourced ABA sufficiently to prompt a transient increase in xylem ABA delivery. More shoot-sourced ABA was detected in the xylem when excised petiole sections were perfused with pH 7 buffer, compared with pH 6 buffer. Sap collected from the fifth oldest leaf of "intact" well-drained plants and plants flooded for 3 h was more alkaline, by approximately 0.4 pH units, than sap collected from the shoot base. Accordingly, xylem [ABA] was increased 2-fold in sap collected from the fifth oldest petiole compared with the shoot base of flooded plants. However, water loss from transpiring, detached leaves was not reduced when the pH of the feeding solution containing 3-h-flooded [ABA] was increased from 6.7 to 7.1 Thus, the extent of the pH-mediated, shoot-sourced ABA redistribution was not sufficient to raise xylem [ABA] to physiologically active levels. Using a detached epidermis bioassay, significant non-ABA anti-transpirant activity was also detected in xylem sap collected at intervals during the first 24 h of soil flooding.

  8. Mass Shootings, Mental Illness, and Gun Control.

    Science.gov (United States)

    Philpott-Jones, Sean

    2018-03-01

    In the wake of the Stoneman Douglas School shooting, Republican and Democratic leaders-like the American electorate they represent-remain sharply divided in their responses to gun violence. They are united in their condemnation of these mass shootings, but they disagree about whether stricter or looser gun control laws are the answer. Those on the right side of the political aisle suggest that the issue is one of mental illness rather than gun control. Conversely, those who are more liberal or progressive in their political learnings are quick to condemn attempts to reframe the issue of mass shootings as a mental health problem. Both sides are wrong. Mass shootings are indeed partially a mental health problem, albeit one poorly addressed by our current laws and policies. But the solution to mass shootings also needs to consider strategies that may reduce gun violence in general. © 2018 The Hastings Center.

  9. Least limiting water range of Udox soil under degraded pastures on different sun-exposed faces

    Science.gov (United States)

    Passos, Renato Ribeiro; Marciano da Costa, Liovando; Rodrigues de Assis, Igor; Santos, Danilo Andrade; Ruiz, Hugo Alberto; Guimarães, Lorena Abdalla de Oliveira Prata; Andrade, Felipe Vaz

    2017-07-01

    The efficient use of water is increasingly important and proper soil management, within the specificities of each region of the country, allows achieving greater efficiency. The South and Caparaó regions of Espírito Santo, Brazil are characterized by relief of `hill seas' with differences in the degree of pasture degradation due to sun exposure. The objective of this study was to evaluate the least limiting water range in Udox soil under degraded pastures with two faces of exposure to the sun and three pedoenvironments. In each pedoenvironment, namely Alegre, Celina, and Café, two areas were selected, one with exposure on the North/West face and the other on the South/East face. In each of these areas, undisturbed soil samples were collected at 0-10 cm depth to determine the least limiting water range. The exposed face of the pasture that received the highest solar incidence (North/West) presented the lowest values in least limiting water range. The least limiting water range proved to be a physical quality indicator for Udox soil under degraded pastures.

  10. Growth and nutrient concentrations of maize in pressmud treated saline-sodic soils

    Directory of Open Access Journals (Sweden)

    D. Muhammad

    2009-05-01

    Full Text Available n open-air pot experiment was conducted to investigate effects of pressmud (PM on saline-sodic soil reclamation, mitigating the adverse effects of saline irrigation and increase of maize (Zea mays L. growth. Pressmud was added at the rate of 0, 5, 10 and 20 Mg ha-1 to pots containing 6.8 kg air dried surface (0-20 cm soil collected from two sites. The increasing levels of PM enhanced maize plant height, shoots and roots biomass in both soils. However, the Soil 2, with initial EC and SAR of 5.43 dS m-1 and 18.67(m mol L-11/2, respectively, produced comparatively more biomass at all PM levels than Soil 1 [silty-clay loam, EC = 6.22 dS m-1, SAR = 20.72 (m mol L- 1 1/2]. The [P] in shoots was maximum at the highest PM in both the soils but the [K] increased with PM levels in Soil 1 and decreased in Soil 2 due to the dilution effect. The Soil 1 maintained several folds more [Na] in shoots and consequently lower K:Na ratio than Soil 2. The post harvest soil pH, Na, Ca+Mg and SAR in saturation extracts decreased with increasing levels of PM as compared to control. Soil 2 released more volume of leachate as compared to Soil 1 but the leachate EC and [Na] were comparable while [Ca+Mg] were relatively higher in Soil 2. The higher removal of total salts from Soil 2 resulted in lower soil pH, EC and SAR in this soil as compared to Soil 1. The increases in crop growth with each increment of PM up to 20 Mg ha-1 in the present study proved the benefits of PM in increasing crop yields and suggested that doses higher than 20 Mg PM ha-1 could be applied to the saline-sodic soils ofthe area to get maximum possible crop yields depending on soil and water quality

  11. Effect of chloride in soil solution on the plant availability of biosolid-borne cadmium.

    Science.gov (United States)

    Weggler, Karin; McLaughlin, Michael J; Graham, Robin D

    2004-01-01

    Increasing chloride (Cl) concentration in soil solution has been shown to increase cadmium (Cd) concentration in soil solution and Cd uptake by plants, when grown in phosphate fertilizer- or biosolid-amended soils. However, previous experiments did not distinguish between the effect of Cl on biosolid-borne Cd compared with soil-borne Cd inherited from previous fertilizer history. A factorial pot experiment was conducted with biosolid application rates of 0, 20, 40, and 80 g biosolids kg(-1) and Cl concentration in soil solution ranging from 1 to 160 mM Cl. The Cd uptake of wheat (Triticum aestivum L. cv. Halberd) was measured and major cations and anions in soil solution were determined. Cadmium speciation in soil solution was calculated using GEOCHEM-PC. The Cd concentration in plant shoots and soil solution increased with biosolid application rates up to 40 g kg(-1), but decreased slightly in the 80 g kg(-1) biosolid treatment. Across biosolid application rates, the Cd concentration in soil solution and plant shoots was positively correlated with the Cl concentration in soil solution. This suggests that biosolid-borne Cd is also mobilized by chloride ligands in soil solution. The soil solution CdCl+ activity correlated best with the Cd uptake of plants, although little of the variation in plant Cd concentrations was explained by activity of CdCl+ in higher sludge treatments. It was concluded that chlorocomplexation of Cd increased the phytoavailability of biosolid-borne Cd to a similar degree as soil (fertilizer) Cd. There was a nonlinear increase in plant uptake and solubility of Cd in biosolid-amended soils, with highest plant Cd found at the 40 g kg(-1) rate of biosolid application, and higher rates (80 g kg(-1)) producing lower plant Cd uptake and lower Cd solubility in soil. This is postulated to be a result of Cd retention by CaCO3 formed as a result of the high alkalinity induced by biosolid application.

  12. SHOOT2.0: An indirect grid shooting package for optimal control problems, with switching handling and embedded continuation

    OpenAIRE

    Martinon , Pierre; Gergaud , Joseph

    2010-01-01

    The SHOOT2.0 package implements an indirect shooting method for optimal control problems. It is specifically designed to handle control discontinuities, with an automatic switching detection that requires no assumptions concerning the number of switchings. Special care is also devoted to the computation of the Jacobian matrix of the shooting function, using the variational system instead of classical finite differences. The package also features an embedded continuation method and an automati...

  13. Soil zymography - A novel technique for mapping enzyme activity in the rhizosphere

    Science.gov (United States)

    Spohn, Marie

    2014-05-01

    The effect plant roots on microbial activity in soil at the millimeter scale is poorly understood. One reason for this is that spatially explicit methods for the study of microbial activity in soil are limited. Here we present a quantitative in situ technique for mapping the distribution of exoenzymes in soil along with some results about the effects of roots on exoenzyme activity in soil. In the first study we showed that both acid and alkaline phosphatase activity were up to 5.4-times larger in the rhizosphere of Lupinus albus than in the bulk soil. While acid phosphatase activity (produced by roots and microorganisms) was closely associated with roots, alkaline phosphatase activity (produced only by microorganisms) was more widely distributed, leading to a 2.5-times larger area of activity of alkaline than of acid phosphatase. These results indicate a spatial differentiation of different ecophysiological groups of organic phosphorus mineralizing organisms in the rhizosphere which might alleviate a potential competition for phosphorus between them. In a second study cellulase, chitinase and phosphatase activities were analyzed in the presence of living Lupinus polyphyllus roots and dead/dying roots (in the same soils 10, 20 and 30 days after cutting the L. polyphyllus shoots). The activity of all three enzymes was 9.0 to 13.9-times higher at the living roots compared to the bulk soil. Microhotspots of cellulase, chitinase and phosphatase activity in the soil were found up to 60 mm away from the living roots. 10 days after shoot cutting, the areas of high activities of cellulase and phosphatase activity were extend up to 55 mm away from the next root, while the extension of the area of chitinase activity did not change significantly. At the root, cellulase and chitinase activity increased first at the root tips after shoot cutting and showed maximal activity 20 days after shoot cutting. The number and activity of microhotspots of chitinase activity was maximal 10

  14. Modeling soil evaporation efficiency in a range of soil and atmospheric conditions using a meta-analysis approach

    Science.gov (United States)

    Merlin, O.; Stefan, V. G.; Amazirh, A.; Chanzy, A.; Ceschia, E.; Er-Raki, S.; Gentine, P.; Tallec, T.; Ezzahar, J.; Bircher, S.; Beringer, J.; Khabba, S.

    2016-05-01

    A meta-analysis data-driven approach is developed to represent the soil evaporative efficiency (SEE) defined as the ratio of actual to potential soil evaporation. The new model is tested across a bare soil database composed of more than 30 sites around the world, a clay fraction range of 0.02-0.56, a sand fraction range of 0.05-0.92, and about 30,000 acquisition times. SEE is modeled using a soil resistance (rss) formulation based on surface soil moisture (θ) and two resistance parameters rss,ref and θefolding. The data-driven approach aims to express both parameters as a function of observable data including meteorological forcing, cut-off soil moisture value θ1/2 at which SEE=0.5, and first derivative of SEE at θ1/2, named Δθ1/2-1. An analytical relationship between >(rss,ref;θefolding) and >(θ1/2;Δθ1/2-1>) is first built by running a soil energy balance model for two extreme conditions with rss = 0 and rss˜∞ using meteorological forcing solely, and by approaching the middle point from the two (wet and dry) reference points. Two different methods are then investigated to estimate the pair >(θ1/2;Δθ1/2-1>) either from the time series of SEE and θ observations for a given site, or using the soil texture information for all sites. The first method is based on an algorithm specifically designed to accomodate for strongly nonlinear SEE>(θ>) relationships and potentially large random deviations of observed SEE from the mean observed SEE>(θ>). The second method parameterizes θ1/2 as a multi-linear regression of clay and sand percentages, and sets Δθ1/2-1 to a constant mean value for all sites. The new model significantly outperformed the evaporation modules of ISBA (Interaction Sol-Biosphère-Atmosphère), H-TESSEL (Hydrology-Tiled ECMWF Scheme for Surface Exchange over Land), and CLM (Community Land Model). It has potential for integration in various land-surface schemes, and real calibration capabilities using combined thermal and microwave

  15. Effect of different soil washing solutions on bioavailability of residual arsenic in soils and soil properties.

    Science.gov (United States)

    Im, Jinwoo; Yang, Kyung; Jho, Eun Hea; Nam, Kyoungphile

    2015-11-01

    The effect of soil washing used for arsenic (As)-contaminated soil remediation on soil properties and bioavailability of residual As in soil is receiving increasing attention due to increasing interest in conserving soil qualities after remediation. This study investigates the effect of different washing solutions on bioavailability of residual As in soils and soil properties after soil washing. Regardless of washing solutions, the sequential extraction revealed that the residual As concentrations and the amount of readily labile As in soils were reduced after soil washing. However, the bioassay tests showed that the washed soils exhibited ecotoxicological effects - lower seed germination, shoot growth, and enzyme activities - and this could largely be attributed to the acidic pH and/or excessive nutrient contents of the washed soils depending on washing solutions. Overall, this study showed that treated soils having lower levels of contaminants could still exhibit toxic effects due to changes in soil properties, which highly depended on washing solutions. This study also emphasizes that data on the As concentrations, the soil properties, and the ecotoxicological effects are necessary to properly manage the washed soils for reuses. The results of this study can, thus, be utilized to select proper post-treatment techniques for the washed soils. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Cytokinin induced shoot regeneration and flowering of Scoparia dulcis L. (Scrophulariaceae)-an ethnomedicinal herb.

    Science.gov (United States)

    Premkumar, G; Sankaranarayanan, R; Jeeva, S; Rajarathinam, K

    2011-06-01

    To develop an improved protocol for micropropagation of ethnomedicinally important Scoparia dulcis (S. dulcis) L. Explants were inoculated on MS basal medium supplemented with kinetin and 6-benzylaminopurine for shoot bud induction. To enhance the shoot induction, various auxins like 3-indoleacetic acid or 3-indolebutyric acid or α-naphthylacetic acid were tested along with 2.32 M KI and 4.44 µM BAP. The regenerated shoots were rooted in half strength MS medium supplemented with various concentrations of IAA, IBA or NAA. After roots were developed, the plantlets were transplanted to pots filled with vermiculate and sand and kept in growth chamber with 70%-80% humidity under 16 h photoperiod. After acclimatization, the plantlets were transferred to the garden and survival percentage was calculated. Data were statistically analyzed and means were compared using Duncan's multiple range test (Pdulcis. Shoot induction on young leaf explants was most successful in MS medium supplemented with combination of two cytokinins (2.32 µM KI and 4.44 µM BAP) 2.85 µM IAA, 10% CM and 1 483.79 µM adenine sulfate. A single young leaf explant was capable of producing 59 shoots after 13 days of culture. Flower was induced in medium supplemented with combination of KI and BAP. Cytokinins are the key factor to induce the direct shoot regeneration and flowering of S. dulcis.

  17. School shootings: law enforcement and school district networking

    OpenAIRE

    Topadzhikyan, Tigran

    2013-01-01

    CHDS State/Local School shootings have happened in the past and will happen again. The history of school shootings prompts all stakeholders to look at ways to prevent them from happening, and if they do happen, to be resilient. Change is needed in the prevention of school shootings. The case studies of Virginia Tech, Sandy Hook, E. O. Green Junior High, and Beslan school shootings reveal that the lack of information sharing and lack of communication were flaws; and the incidents might have...

  18. [Effects of Different Kinds of Organic Materials on Soil Heavy Metal Phytoremediation Efficiency by Sedum alfredii Hance].

    Science.gov (United States)

    Yao, Gui-hua; Xu, Hai-zhou; Zhu, Lin-gang; Ma, Jia-wei; Liu, Dan; Ye, Zheng-qian

    2015-11-01

    In this study, a pot experiment was conducted to investigate the effect of clean organic materials i. e., biogas residue (BR), mushroom residue (MR), and bamboo shell (BS) on phytoextraction remediation of two heavy metal contaminated soils (collected from Wenzhou and Fuyang, which referred to "Wenzhou soil" and "Fuyang soil", respectively.) using a cadmium (Cd) and zinc (Zn) hyperaccumulator Sedum alfredii Hance. The results indicated that the effects of organic materials on availabilities of soil heavy metals were different due to different kinds of heavy metals, organic materials, and the application rates of the organic materials. Addition with 5% BR showed the greatest activation to copper (Cu), Zn in Wenzhou soil, and in Fuyang soil 1% BS had the highest activation for Cu, Zn, lead ( Ph) and Cd. Growth of shoot biomass of Sedum alfredii Hance increased with the addition rate of organic materials, and the plant dry weights were increased by 23.7%-93.0%. In Wenzhou soil, only 1% BS treatment had the best effect on Cd uptake and accumulation in shoots of Sedum alfredii Hance, increased by 22.6%, while other treatments were inferior to the control. For Zn, MR treatments were inferior to the control, while other treafments were superior to the control, of which 5% BR, 1% BS and 5% BS exceeded the control by 39. 6%, 32.6% and 23.8%, respectively. In Fuyang soil, for Cd, the treatment effects of 5% BS, 1% BR and 5% BR were the greatest, of which Cd accumulation in shoots exceeded the control by 12.9%, 12.8% and 6.2%, respectively, while Cd accumulations in shoots in all other treatments were less than that of control. For Zn, the treatments of adding organic materials promoted Zn accumulation in shoots of Sedum alfredii Hance, and the best treatments were as follows: 5% BS. 5% BR and 5% MR, exceeded the control by 38.4%, 25.7% and 22.4%, respectively.

  19. Phytoextraction with Brassica napus L.: A tool for sustainable management of heavy metal contaminated soils

    International Nuclear Information System (INIS)

    Grispen, Veerle M.J.; Nelissen, Hans J.M.; Verkleij, Jos A.C.

    2006-01-01

    Phytoextraction is a promising tool to extract metals from contaminated soils and Brassica napus L. seems to be a possible candidate species for this purpose. To select accessions with the ability to accumulate cadmium, hydroponically grown 21 day old seedlings of 77 B. napus L. accessions were exposed to 0.2 μM CdSO 4 for an additional 10 days. The effects of Cd on several parameters were quantified i.e.; shoot Cd concentration ([Cd] shoot ), total amount of Cd in shoots (Total Cd) and the shoot to root Cd concentration ratio (S/R ratio). Though generally natural variation was low for [Cd] shoot , Total Cd and S/R ratio, a number of accessions could be selected. Our results indicated that Total Cd and S/R ratio are independent parameters for Cd accumulation and translocation. The selected varieties were then tested in field experiments on two locations nearby metal smelters. The two locations differed in extractable soil Cd, Zn, Ca concentration and pH levels. On both locations B. napus L. accessions showed significant differences in [Cd] shoot and Total Cd. Furthermore we found significant correlations between Cd and Zn accumulation in shoots. There were site-specific effects with respect to Cd accumulation in the B. napus L. accessions, however, two accessions seem to perform equally well on both sites. The results of the field experiment suggest that certain B. napus L. accessions are suitable for phytoextraction of moderately heavy metal contaminated soils. - A screening for natural variation in Cd accumulated by 77 Brassica napus L. yielded candidate phytoextraction accessions for agricultural practice

  20. Phytoextraction with Brassica napus L.: A tool for sustainable management of heavy metal contaminated soils

    Energy Technology Data Exchange (ETDEWEB)

    Grispen, Veerle M.J. [Department of Ecology and Physiology of Plants, Vrije Universiteit, De Boelelaan 1085, NL-1081 HV Amsterdam (Netherlands); Nelissen, Hans J.M. [Department of Ecology and Physiology of Plants, Vrije Universiteit, De Boelelaan 1085, NL-1081 HV Amsterdam (Netherlands); Verkleij, Jos A.C. [Department of Ecology and Physiology of Plants, Vrije Universiteit, De Boelelaan 1085, NL-1081 HV Amsterdam (Netherlands)]. E-mail: jos.verkleij@falw.vu.nl

    2006-11-15

    Phytoextraction is a promising tool to extract metals from contaminated soils and Brassica napus L. seems to be a possible candidate species for this purpose. To select accessions with the ability to accumulate cadmium, hydroponically grown 21 day old seedlings of 77 B. napus L. accessions were exposed to 0.2 {mu}M CdSO{sub 4} for an additional 10 days. The effects of Cd on several parameters were quantified i.e.; shoot Cd concentration ([Cd]{sub shoot}), total amount of Cd in shoots (Total Cd) and the shoot to root Cd concentration ratio (S/R ratio). Though generally natural variation was low for [Cd]{sub shoot}, Total Cd and S/R ratio, a number of accessions could be selected. Our results indicated that Total Cd and S/R ratio are independent parameters for Cd accumulation and translocation. The selected varieties were then tested in field experiments on two locations nearby metal smelters. The two locations differed in extractable soil Cd, Zn, Ca concentration and pH levels. On both locations B. napus L. accessions showed significant differences in [Cd]{sub shoot} and Total Cd. Furthermore we found significant correlations between Cd and Zn accumulation in shoots. There were site-specific effects with respect to Cd accumulation in the B. napus L. accessions, however, two accessions seem to perform equally well on both sites. The results of the field experiment suggest that certain B. napus L. accessions are suitable for phytoextraction of moderately heavy metal contaminated soils. - A screening for natural variation in Cd accumulated by 77 Brassica napus L. yielded candidate phytoextraction accessions for agricultural practice.

  1. The effect of short-range spatial variability on soil sampling uncertainty

    Energy Technology Data Exchange (ETDEWEB)

    Perk, Marcel van der [Department of Physical Geography, Utrecht University, P.O. Box 80115, 3508 TC Utrecht (Netherlands)], E-mail: m.vanderperk@geo.uu.nl; De Zorzi, Paolo; Barbizzi, Sabrina; Belli, Maria [Agenzia per la Protezione dell' Ambiente e per i Servizi Tecnici (APAT), Servizio Laboratori, Misure ed Attivita di Campo, Via di Castel Romano, 100-00128 Roma (Italy); Fajgelj, Ales; Sansone, Umberto [International Atomic Energy Agency (IAEA), Agency' s Laboratories Seibersdorf, A-1400 Vienna (Austria); Jeran, Zvonka; Jacimovic, Radojko [Jozef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia)

    2008-11-15

    This paper aims to quantify the soil sampling uncertainty arising from the short-range spatial variability of elemental concentrations in the topsoils of agricultural, semi-natural, and contaminated environments. For the agricultural site, the relative standard sampling uncertainty ranges between 1% and 5.5%. For the semi-natural area, the sampling uncertainties are 2-4 times larger than in the agricultural area. The contaminated site exhibited significant short-range spatial variability in elemental composition, which resulted in sampling uncertainties of 20-30%.

  2. The effect of short-range spatial variability on soil sampling uncertainty.

    Science.gov (United States)

    Van der Perk, Marcel; de Zorzi, Paolo; Barbizzi, Sabrina; Belli, Maria; Fajgelj, Ales; Sansone, Umberto; Jeran, Zvonka; Jaćimović, Radojko

    2008-11-01

    This paper aims to quantify the soil sampling uncertainty arising from the short-range spatial variability of elemental concentrations in the topsoils of agricultural, semi-natural, and contaminated environments. For the agricultural site, the relative standard sampling uncertainty ranges between 1% and 5.5%. For the semi-natural area, the sampling uncertainties are 2-4 times larger than in the agricultural area. The contaminated site exhibited significant short-range spatial variability in elemental composition, which resulted in sampling uncertainties of 20-30%.

  3. Coal Waste Powder Amendment and Arbuscular Mycorrhizal Fungi Enhance the Growth of Jabon (Anthocephalus cadamba Miq Seedling in Ultisol Soil Medium

    Directory of Open Access Journals (Sweden)

    Sri Wilarso Budi

    2013-03-01

    Full Text Available Coal powder waste application on low nutrient media is expected to be able to increase plant growth and to improve Arbuscular mycorrhizal fungi (AMF development. The objective of this research was to determine the effect of coal waste powder on the growth of Anthocephallus cadamba Jack and AMF development grown on ultisol soil. Two factors in a completely randomised experimental design was conducted under greenhouse conditions and Duncan Multiple Range Test was used to analyse of the effect the treatment. The first factor was ultisol soil ammended with coal waste powder (control, soil amanded with coal waste 5%, soil amanded with coal waste 10% and soil amanded with coal waste 15% and the second factor was AMF inoculation (uninoculated control, inoculated with Gigaspora margarita. Plant height, diameter, shoot dry weight, percentage of AMF colonization and nutrient uptake were measured in this experiment. Results of this study showed that coal amendment and AMF when applied separately significantly increased height, diameter, shoot dry weight, root dry weight and nutrient uptake of 12 weeks A. cadamba seedling, but when the coal waste powder and AMF were combined the plant growth parameters were lower than those applied separately but significantly higher than control. The application of coal waste powder or AMF in ultisol soil could increase A. cadamba growth and development.

  4. Phytoremediation potential of weeds in heavy metal contaminated soils of the Bassa Industrial Zone of Douala, Cameroon.

    Science.gov (United States)

    Lum, A Fontem; Ngwa, E S A; Chikoye, D; Suh, C E

    2014-01-01

    Phytoremediation is a promising option for reclaiming soils contaminated with toxic metals, using plants with high potentials for extraction, stabilization and hyperaccumulation. This study was conducted in Cameroon, at the Bassa Industrial Zone of Douala in 2011, to assess the total content of 19 heavy metals and 5 other elements in soils and phytoremediation potential of 12 weeds. Partial extraction was carried out in soil, plant root and shoot samples. Phytoremediation potential was evaluated in terms of the Biological Concentration Factor, Translocation Factor and Biological Accumulation Coefficient. The detectable content of the heavy metals in soils was Cu:70-179, Pb:8-130, Zn:200-971, Ni:74-296, Co:31-90, Mn:1983-4139, V:165-383, Cr:42-1054, Ba:26-239, Sc:21-56, Al:6.11-9.84, Th:7-22, Sr:30-190, La:52-115, Zr:111-341, Y:10-49, Nb:90-172 in mg kg(-1), and Ti:2.73-4.09 and Fe:12-16.24 in wt%. The contamination index revealed that the soils were slightly to heavily contaminated while the geoaccumulation index showed that the soils ranged from unpolluted to highly polluted. The concentration of heavy metals was ranked as Zn > Ni > Cu > V > Mn > Sc > Co > Pb and Cr in the roots and Mn > Zn > Ni > Cu > Sc > Co > V > Pb > Cr > Fe in the shoots. Dissotis rotundifolia and Kyllinga erecta had phytoextraction potentials for Pb and Paspalum orbicularefor Fe. Eleusine indica and K. erecta had phytostabilisation potential for soils contaminated with Cu and Pb, respectively.

  5. [Effects of combined pollution of lead and benzo[a] pyrene on seed growth of wheat in soils].

    Science.gov (United States)

    Wang, Hong-Qi; Wang, Shuai; Ning, Shao-Wei; Sun, Yan-Ling; Hou, Ze-Qing

    2011-03-01

    Seed germination, root elongation, shoot elongation and ratio of shoot to root of wheat in soils polluted by lead (Pb) and benzo (a)pyrene (B[a] P) with medium-low concentrations were studied to reveal the ecological effects of combined pollution and screen the indicative markers. Results indicated that seed germination was not sensitive to single or combined pollution of Pb or B[a] P. Root elongation was inhibited by single pollution of Pb or B[a]P to different extents. Extensive interactions between Pb and B[a]P occurred to root elongation of wheat, including synergistic-stimulatory effect and antagonistic-inhibitory effect. The joint action was mainly antagonistic. Single pollution of B [a] P had an inhibitory effect on shoot elongation. Under combined pollution conditions, the shoot elongation of wheat correlated well with Pb contents (p pollutants had little effect on shoot elongation of wheat. The joint action on shoot elongation was consistently antagonistic. The response pattern of the ratio of shoot to root was similar to the response pattern of shoot elongation. However, the former had better correlation than the latter, indicating it as a more suitable indicative marker for Pb pollution. If lead acetate was employed instead of lead nitrate, longer root elongation, shorter shoot elongation and no effect on ratio of shoot to root were found. Therefore, the forms of Pb salt had significant influence on seed growth of wheat in soils.

  6. The selection of hyperaccumulators for phytoremediation of uranium-contaminated soils and their uranium-accumulating characters

    International Nuclear Information System (INIS)

    Tang Li; Ren Yamin; Xu Jun; Yao Zhongwei; Xia Chuanqin; Bo Yun; Deng Dachao

    2009-01-01

    A pot experiment was conducted to investigate the possibility for phytoremediation of U-contaminated soils. The plants of cruciferae (8 species), malvaceae or compositae were planted for 55 days in the U-contaminated soils (100 mg·kg -1 ). The samples were analyzed using an inductively-coupled plasma atomic emission spectrometer (ICP-AES). The results showed that U concentration was the highest in shoots of Chinese mustard (var.Texuanzhacai, 1115 mg·kg -1 ), the highest U removal from U-contaminated soils to plants occurred in the shoots of Artemisia argyi(1113 μg per pot). For the Chinese mustard (var.Paoqingcai, var. Texuanzhacai), uranium concentration in shoots was higher than in roots, and bioaccumulation factors (BFs) and transfer factors (TFs) were more than one. They showed better suitability for phytoremediation of U than other plants due to their high U accumulation in the aboveground tissues. (authors)

  7. Using Plants for the Bioremediation (Phyto-remediation) of Chromium-Contaminated Soils

    International Nuclear Information System (INIS)

    Abdel-Sabour, M.F.; Al-Salama, Y.J.

    2003-01-01

    A trial was made to study the use of hyper accumulator plant species to extract Cr out of contaminated soils. Three soils (A,B, and C) were selected in this experiment, Soil A: Polluted soil from El-Gabal El-Asfer farm. (subjected to sewage effluent irrigation for more than 75 years). Soil B: Polluted soil from Bahtem area (subjected to sewage effluent irrigation for more than 30 years). Soil C: Polluted soil from Mostorud area (irrigated with contaminated water for more than 30 years due to direct discharge of industrial wastewater to irrigation water canals). Four Kg of each air-dried surface soil sample (0-20 cm) were packed in plastic containers in three replicates. Four plant species tested in this study namely, Sorghum (Sorghum Vulgar L.), Clover (Trifolium Pretense L.), Panikum (Panicum antidotal) and Canola (Brassica Napous.); were grown on each tested soil in a complete randomized block experimental design. Plant shoots were harvested every 60 days (three cuts) for sorghum, clover and panikum. In case of canola plants, the shoots were harvested after 60 days (vegetative stage) and 85 days(fruiting stage). The roots of all species were collected after the final cut. Initial and final soil samples were taken for Cr analyses using neutron activation analyses technique (NAA)

  8. Water Status Related Root-to-Shoot Communication Regulates the Chilling Tolerance of Shoot in Cucumber (Cucumis sativus L.) Plants.

    Science.gov (United States)

    Zhang, Zi-Shan; Liu, Mei-Jun; Gao, Hui-Yuan; Jin, Li-Qiao; Li, Yu-Ting; Li, Qing-Ming; Ai, Xi-Zhen

    2015-10-16

    Although root-to-shoot communication has been intensively investigated in plants under drought, few studies have examined root-to-shoot communication under chilling. Here we explored whether root-to-shoot communication contributes to the chilling-light tolerance of cucumber shoots and clarified the key signal involves in this communication. After leaf discs chilling-light treatment, the photoinhibitions of Photosystem I (PSI) and Photosystem II (PSII) were similar in leaf discs of two cucumber varieties (JY-3 and JC-4). When the whole plants, including roots, were chilled under light, the photosynthetic performances in JC-4 leaves decreased more seriously than that in JY-3 leaves. However, when the water status of leaves was maintained by warming roots or floating the attached leaves on water, the PSII activity and amount of PSI in the leaves of the two varieties were similar after chilling-light treatment. In addition, the differences of PSII activities and amount of PSI between the two varieties under whole plant chilling-light treatment were independent of ABA pretreatment. Above results indicate that (1) the better water status in leaves under chilling contributes to the higher chilling tolerance of JY-3; (2) the water status, rather than an ABA signal, dominates root-to-shoot communication under chilling and the chilling tolerance of cucumber shoot.

  9. Acid drainage from coal mining: Effect on paddy soil and productivity of rice.

    Science.gov (United States)

    Choudhury, Burhan U; Malang, Akbar; Webster, Richard; Mohapatra, Kamal P; Verma, Bibhash C; Kumar, Manoj; Das, Anup; Islam, Mokidul; Hazarika, Samarendra

    2017-04-01

    Overburden and acid drainage from coal mining is transforming productive agricultural lands to unproductive wasteland in some parts of Northeast India. We have investigated the adverse effects of acid mine drainage on the soil of rice paddy and productivity by comparing them with non-mined land and abandoned paddy fields of Jaintia Hills in Northeast India. Pot experiments with a local rice cultivar (Myngoi) as test crop evaluated biological productivity of the contaminated soil. Contamination from overburden and acid mine drainage acidified the soil by 0.5 pH units, increased the exchangeable Al 3+ content 2-fold and its saturation on clay complexes by 53%. Available sulfur and extractable heavy metals, namely Fe, Mn and Cu increased several-fold in excess of critical limits, while the availability of phosphorus, potassium and zinc contents diminished by 32-62%. The grain yield of rice was 62% less from fields contaminated with acid mine drainage than from fields that have not suffered. Similarly, the amounts of vegetation, i.e. shoots and roots, in pots filled with soil from fields that received acid mine drainage were 59-68% less than from uncontaminated land (average shoot weight: 7.9±2.12gpot -1 ; average root weight: 3.40±1.15gpot -1 ). Paddy fields recovered some of their productivity 4years after mining ceased. Step-wise multiple regression analysis affirmed that shoot weight in the pots and grain yield in field were significantly (p<0.01) and positively influenced by the soil's pH and its contents of K, N and Zn, while concentration of S in excess of threshold limits in contaminated soil significantly (p<0.01) reduced the weight of shoots in the pots and grain yield in the field. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Irradiated Sewage Sludge for Production of Fennel Plants in Sandy Soil

    International Nuclear Information System (INIS)

    El-Motaium, R. A.; Abo El-Seoud, M. A.

    2004-01-01

    Irradiated sewage sludge (SS) has proved to be a useful organic fertilizer particularly for sandy soil. The objective of this study is to compare the response of fennel (Foeniculum vulgare L.) plants growing in sandy soil to different fertilizer regimes, organic vs. mineral. In a field experiment four levels (20, 40, 60, 80 t/ha) of irradiated and non-irradiated sewage sludge were incorporated into sandy soil, in addition to the control treatment (mineral fertilizer). Samples analysis included the biomass production at the vegetative and flowering stages, chlorophyll content, total and reducing sugars and heavy metals content of the shoots. The data indicate that the biomass production has dramatically increased as the sludge application rate increased in both irradiated and non-irradiated plots. However, the increase was significantly higher under all irradiated treatments than the corresponding rates of non-irradiated treatments at both the vegetative and flowering stages. Also, the biomass production at all levels of application was higher than the control, receiving mineral fertilizer. At the vegetative stage, the biomass values ranged from 3.1 g/plant for the control to 10.2 and 34.1 g/plant at 80 t/ha for non-irradiated and irradiated sewage sludge, respectively. Whereas, at the flowering stage the values ranged from 9.8 g/plant for the control to 23.9 and 65.1 g/plant at 80 t/ha for non-irradiated and irradiated sewage sludge, respectively. Total sugars, reducing sugar, non-reducing sugar, and chlorophyll content has increased as the sludge application rate increased. At 80t/ha application rate of irradiated sludge, the reducing sugars content was 29.39 mg/g DW at the vegetative stage and 37.85 mg/g DW at the flowering stage. Reducing sugars recorded lower values in the control plants, 14.54 mg/g DW at the vegetative stage and 18.78 mg/g DW at the flowering stage. Heavy metals (Zn, Fe, Pb, Cd) of the shoots was also determined. Sewage sludge was a good

  11. Arsenic contamination of soils and agricultural plants through irrigation water in Nepal

    International Nuclear Information System (INIS)

    Dahal, B.M.; Fuerhacker, M.; Mentler, A.; Karki, K.B.; Shrestha, R.R.; Blum, W.E.H.

    2008-01-01

    This study monitored the influence of arsenic-contaminated irrigation water on alkaline soils and arsenic uptake in agricultural plants at field level. The arsenic concentrations in irrigation water ranges from -1 where the arsenic concentrations in the soils were measured from 6.1 to 16.7 mg As kg -1 . The arsenic content in different parts of plants are found in the order of roots > shoots > leaves > edible parts. The mean arsenic content of edible plant material (dry weight) were found in the order of onion leaves (0.55 mg As kg -1 ) > onion bulb (0.45 mg As kg -1 ) > cauliflower (0.33 mg As kg -1 ) > rice (0.18 mg As kg -1 ) > brinjal (0.09 mg As kg -1 ) > potato ( -1 ). - The arsenic content in soil and plants is influenced by the degree of arsenic amount in irrigated water

  12. Initial growth of Schizolobium parahybae in Brazilian Cerrado soil under liming and mineral fertilization

    Directory of Open Access Journals (Sweden)

    Ademilson Coneglian

    Full Text Available ABSTRACT High prices and the scarcity of hardwoods require the use of alternative wood sources, such as the Guapuruvu (Schizolobium parahybae, an arboreal species native to the Atlantic Forest, which has fast growth and high market potential. However, there is no information on its cultivation in the Brazilian Cerrado. Thus, this study aimed to analyze the contribution of mineral fertilization and liming in a Cerrado soil on the initial growth of Schizolobium parahybae. The experiment was set in a randomized block design, with 4 treatments (Cerrado soil; soil + liming; soil + fertilizer; and soil + fertilizer + liming and 15 replicates. The following variables were analyzed: plant height, stem diameter, number of leaves, total, shoot, leaf, root and stem dry matter, and root/shoot ratio. The obtained data were subjected to the analysis of variance, Tukey test and regression analysis. During the initial growth, Schizolobium parahybae can be cultivated in a Brazilian Cerrado soil only under mineral fertilization, with no need for soil liming.

  13. Assessing the Effect of Prometryn Soil Residue on Soil Microbial Biomass and Different Crops using Bioassay Test

    Directory of Open Access Journals (Sweden)

    mohamad taghi alebrahim

    2016-09-01

    after germination. The pots were kept for 30 days under controlled conditions. Shoot and root biomass production was measured 30 days after emergence. At harvest, growth parameters including the dry weight of shoots and roots were determined. The data were subjected to analysis of variance by computer facilities, using Mstatc software. Plant response to prometryn residues was fitted with sigmoidal 3 and 4 parametric equations to the shoot biomass data as a function of the herbicide residue concentrations and was used to calculate the doses for 50% inhibition of shoot growth (ED50. In another experiment the effect of prometryn concentrations (0, 0.0033, 0.0166, 0.033, 0.066, 0.1 and 0.166 mg. kg-1soil on soil microbial activity was determined using titration method in controlled conditions. Results and Discussion: Plant response to increasing concentration of prometryn, in general, followed a classical dose response relationship. The logistic model fitted well to the root and shoot plants response herbicide concentrations. Results showed that the shoot and root dry matter were significantly affected by increasing prometryn soil residue in all crops (plettuce>beet>barely. Based on the mechanism of action of prometryn and its best efficiency on board leaf plants control, the least biomass reduction obtained for barley is understandable. In general, this is safe to plant a susceptible species if the plant-available residue were less than the species ED10 value, and there would be a great risk for different levels of crop damage if the plant-available residue were higher than ED50 values of the species. Comparisons between species allow the safe selection of a crop that has a critical ED50 level lower than the residue level in the soil. Alternatively, planting a sensitive species could be delayed until the residue level in the soil is less than the critical level. In the Southwest areas of Iran, these crops are often sown few months after the application of a residual

  14. Pilot scale aided-phytoremediation of a co-contaminated soil.

    Science.gov (United States)

    Marchand, Charlotte; Mench, Michel; Jani, Yahya; Kaczala, Fabio; Notini, Peter; Hijri, Mohamed; Hogland, William

    2018-03-15

    A pilot scale experiment was conducted to investigate the aided-phytoextraction of metals and the aided-phytodegradation of petroleum hydrocarbons (PHC) in a co-contaminated soil. First, this soil was amended with compost (10% w/w) and assembled into piles (Unp-10%C). Then, a phyto-cap of Medicago sativa L. either in monoculture (MS-10%C) or co-cropped with Helianthus annuus L. as companion planting (MSHA-10%C) was sown on the topsoil. Physico-chemical parameters and contaminants in the soil and its leachates were measured at the beginning and the end of the first growth season (after five months). In parallel, residual soil ecotoxicity was assessed using the plant species Lepidium sativum L. and the earthworm Eisenia fetida Savigny, 1826, while the leachate ecotoxicity was assessed using Lemna minor L. After 5months, PH C10-C40, PAH-L, PAH-M PAH-H, Pb and Cu concentrations in the MS-10%C soil were significantly reduced as compared to the Unp-10%C soil. Metal uptake by alfalfa was low but their translocation to shoots was high for Mn, Cr, Co and Zn (transfer factor (TF) >1), except for Cu and Pb. Alfalfa in monoculture reduced electrical conductivity, total organic C and Cu concentration in the leachate while pH and dissolved oxygen increased. Alfalfa co-planting with sunflower did not affect the extraction of inorganic contaminants from the soil, the PAH (M and H) degradation and was less efficient for PH C10-C40 and PAH-L as compared to alfalfa monoculture. The co-planting reduced shoot and root Pb concentrations. The residual soil ecotoxicity after 5months showed a positive effect of co-planting on L. sativum shoot dry weight (DW) yield. However, high contaminant concentrations in soil and leachate still inhibited the L. sativum root DW yield, earthworm development, and L. minor growth rate. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Characteristics of schools in which fatal shootings occur.

    Science.gov (United States)

    de Apodaca, Roberto Flores; Brighton, Lauren M; Perkins, Ashley N; Jackson, Kiana N; Steege, Jessica R

    2012-04-01

    School-based violence, and fatal school shootings in particular, have gained increased attention in the media and psychological literature. Most reports have focused on the characteristics of perpetrators, but there is a growing awareness that school-related factors may also influence the occurrence of fatal school shootings. The current study examined several key characteristics of all schools where random (38) and targeted (96) fatal shootings occurred in the United States between 1966 and 2009. These were compared with a group (138) of schools randomly selected to represent the population of all schools in the United States. The size of a school's enrollment, urban or suburban locale, public funding, and predominantly non-white enrollment were positively associated with fatal shootings. Universities and colleges were disproportionately associated with random shootings and high schools with targeted ones. It was proposed that characteristics of schools that allow feelings of anonymity or alienation among students may help create environmental conditions associated with fatal school shootings. Implications for future research and interventions are considered.

  16. Differences between height- and light-dependent changes in shoot traits in five deciduous tree species.

    Science.gov (United States)

    Osada, Noriyuki; Okabe, Yoshihiko; Hayashi, Daisuke; Katsuyama, Tomonori; Tokuchi, Naoko

    2014-01-01

    The effects of tree height on shoot traits may in some cases differ in magnitude and direction from the effects of light. Nevertheless, general patterns of change in shoot traits in relation to variations in height and light have not so far been revealed. A comprehensive analysis of the differences between the effects of height and light on a range of leaf and shoot traits is important for the scaling of these traits to individual trees. We investigated the biomass allocation and structure of current-year shoots at the top of the crowns of five deciduous tree species in Japan. Height effect was investigated by comparing shoot traits among trees of different heights growing under a high light environment. The effects of light were examined by comparing saplings growing in high- and low-light environments. The effects of light were significant for most traits, while those of height were not significant for some traits. The magnitudes of the effects of light were larger than those of height for most traits related to biomass allocation. There was an extreme difference between the effects of height and light in the direction of change in the length of current-year shoots and in the number of standing leaves. The measures of both parameters increased with the increase in light, but decreased with the increase in tree height. Thus, the effects of height and light on diverse traits at the level of current-year shoots were not always similar. These results suggest that great care must be taken when scaling shoot traits from small trees to tall trees because the effects of height and light can be complex.

  17. Assessment of Soil-Gas and Soil Contamination at the Former Military Police Range, Fort Gordon, Georgia, 2009-2010

    Science.gov (United States)

    Falls, W. Fred; Caldwell, Andral W.; Guimaraes, Wladmir B.; Ratliff, W. Hagan; Wellborn, John B.; Landmeyer, James E.

    2011-01-01

    Soil gas and soil were assessed for organic and inorganic contaminants at the former military police range at Fort Gordon, Georgia, from May to September 2010. The assessment evaluated organic contaminants in soil-gas samplers and inorganic contaminants in soil samples. This assessment was conducted to provide environmental contamination data to Fort Gordon pursuant to requirements of the Resource Conservation and Recovery Act Part B Hazardous Waste Permit process. Soil-gas samplers deployed and collected from May 20 to 24, 2010, identified masses above method detection level for total petroleum hydrocarbons, gasoline-related and diesel-related compounds, and chloroform. Most of these detections were in the southwestern quarter of the study area and adjacent to the road on the eastern boundary of the site. Nine of the 11 chloroform detections were in the southern half of the study area. One soil-gas sampler deployed adjacent to the road on the southern boundary of the site detected a mass of tetrachloroethene greater than, but close to, the method detection level of 0.02 microgram. For soil-gas samplers deployed and collected from September 15 to 22, 2010, none of the selected organic compounds classified as chemical agents and explosives were detected above method detection levels. Inorganic concentrations in the five soil samples collected at the site did not exceed the U.S. Environmental Protection Agency regional screening levels for industrial soil and were at or below background levels for similar rocks and strata in South Carolina.

  18. Changes in soil solution Zn and pH and uptake of Zn by arbuscular mycorrhizal red clover in Zn-contaminated soil.

    Science.gov (United States)

    Li, X; Christie, P

    2001-01-01

    Red clover plants inoculated with Glomus mosseae were grown in a sterile pasture soil containing 50 mg Zn kg(-1) in 'Plexiglas' (acrylic) containers with nylon net partitions (30 microm mesh) designed to separate the soil into a central root zone and two outer zones for hyphal growth with no root penetration. Two porous plastic soil moisture samplers were installed in each pot, one in the root compartment and the other in one of the hyphal compartments. The soil in the outer compartments was amended with one of the four application rates of Zn (as ZnSO4) ranging from 0 to 1000 mg kg(-1). Non-mycorrhizal controls were included, and there were five replicates of each treatment in a randomised block in a glasshouse. Uninoculated plants received supplementary P to avoid yield limitation due to low soil P status. Plants grew in the central compartment for nine weeks. Soil moisture samples were collected 4, 24 and 62 days after sowing to monitor changes in the Zn concentration and pH of the soil solution. At harvest, the mean mycorrhizal infection rate of inoculated plants ranged from 29% to 34% of total root length and was little affected by Zn application. Root and shoot yields were not affected by mycorrhizal infection. Plant Zn concentration and uptake were lower in mycorrhizal plants than non-mycorrhizal controls, and this effect was more pronounced with increasing Zn application rate to the soil. Soil solution Zn concentrations were lower and pH values were higher in mycorrhizal treatments than non-mycorrhizal controls and the mycorrhiza effect was more pronounced at higher Zn application rates. The protective effect of mycorrhiza against plant Zn uptake may have been associated with changes in Zn solubility mediated by changes in the soil solution pH, or by immobilisation of Zn in the extraradical mycelium.

  19. Liquid shoot culture of Salvia officinalis L. for micropropagation and production of antioxidant compounds; effect of triacontanol

    Directory of Open Access Journals (Sweden)

    Izabela Grzegorczyk

    2011-01-01

    Full Text Available Liquid shoot culture of Salvia officinalis L. in MS medium containing IAA (0.1 mg l-1 and BAP (0.45 mg l-1 was developed and evaluated in relation to shoot multiplication and antioxidant compound (carnosic acid, carnosol and rosmarinic acid accumulation. In the liquid medium, on average, 3 new shoots per explant (shoot tip were obtained within 3 weeks. The shoots produced 8.2±0.02 mg of diterpenoids and 31.2±0.29 mg of rosmarinic acid per gram of dry weight. Shoot proliferation and diterpenoid content increased when triacontanol (5, 10 or 20 pg l-1 was added to the liquid medium. In optimum conditions (at 20 pg l-1 TRIA almost 7 shoots were formed per explant after 3 weeks. An increase in diterpenoid production (expressed as the sum of carnosol and carnosic acid ranged from 30% to 50% and dependended on triacontanol concentration tested. The level of diterpenoids in triacontanol-treated shoots was similar to the content of compounds in commercial herbal product (dried leaves of S. officinalis (10-12 mg g-1 dry wt. Triacontanol did not increase rosmarinic acid production, but the content of the phenolic as compound in shoots grown in liquid culture (31 mg g-1 dry wt was even 24 times higher compared to samples of dried leaves of S. officinalis plants. We also demonstrated that the highest amounts of CA, Car and RA were accumulated in young, top parts of sage shoots. This observation could be useful for improving the selection of material for the extraction of natural antioxidants from S. officinalis.

  20. Al-Fe interactions and growth enhancement in Melastoma malabathricum and Miscanthus sinensis dominating acid sulphate soils.

    Science.gov (United States)

    Watanabe, Toshihiro; Jansen, Steven; Osaki, Mitsuru

    2006-12-01

    Plants growing in acid sulphate soils are subject to high levels of Al availability, which may have effects on the growth and distribution of these species. Although Fe availability is also high in acid sulphate soils, little is known about the effect of Fe on the growth of native plants in these soils. Two species dominating this soil type in Asia, viz. Melastoma malabathricum and Miscanthus sinensis were grown hydroponically in a nutrient solution with different concentrations of Al and Fe. Melastoma malabathricum is found to be sensitive to Fe (40 and 100 microm). Application of 500 microm Al, however, completely ameliorates Fe toxicity and is associated with a decrease of Fe concentration in shoots and roots. The primary reason for the Al-induced growth enhancement of M. malabathricum is considered to be the Al-induced reduction of toxic Fe accumulation in roots and shoots. Therefore, Al is nearly essential for M. malabathricum when growing in acid sulphate soils. In contrast, application of both Fe and Al does not reduce the growth of M. sinensis, and Al application does not result in lower shoot concentrations of Fe, suggesting that this grass species has developed different mechanisms for adaptation to acid sulphate soils.

  1. Root~Shoot Growth Interactions of Sorghmn (Sorghwn Bicolor L ...

    African Journals Online (AJOL)

    growth. Studies on root-shoot intera'ctions in relation to mechanical impedance have only investigated the effect on shoots of ... growth regulators that may be responsible. Studies of root-shoot ... of germinating seeds to MI leaving roots in rela-.

  2. Effect of arbuscular mycorrhizal fungi on trace metal uptake by sunflower plants grown on cadmium contaminated soil.

    Science.gov (United States)

    Hassan, Saad Eldin; Hijri, Mohamed; St-Arnaud, Marc

    2013-09-25

    Trace metal (TM) pollution of soil is a worldwide problem that threatens the quality of human and environmental health. Phytoremediation using plants and their associated microbes has been increasingly used as a green technology for cleaning up TM-polluted soils. In this study, we investigated the effect of inoculating two arbuscular mycorrhizal fungal isolates, Rhizophagus irregularis and Funneliformis mosseae, on trace metal uptake by sunflower plants grown in soils contaminated with three different Cd concentrations in a greenhouse trial. Root colonization, plant dry mass, and plant tissue cadmium (Cd), zinc (Zn), and copper (Cu) concentrations in roots and shoots were determined after sunflower harvesting. We found that root mycorrhizal colonization rates were not significantly affected by Cd treatments. At low soil Cd concentration, R. irregularis-inoculated plants had significantly higher shoot Cd and Zn concentrations than plants inoculated with F. mosseae and non-inoculated plants. However, at high soil Cd concentrations, F. mosseae-inoculated plants had significantly lower shoot Cd and Zn concentrations and biological concentration factor (BCF) values than plants inoculated with R. irregularis and non-inoculated plants. Cadmium was mainly translocated in shoot tissues of R. irregularis-inoculated plants and sequestered in the rhizosphere of F. mosseae-inoculated plants. The results indicate that these AMF strains mediate different tolerance strategies to alleviate TM toxicity in their host plants and that inoculation with the R. irregularis strain can be used for Cd phytoextraction, whereas this F. mosseae strain can be useful for Cd and Zn phytostabilization of contaminated soil. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Protocol optimization for in vitro shoot multiplication of Jackfruit ...

    African Journals Online (AJOL)

    Jemal

    2017-01-11

    Jan 11, 2017 ... Protocol optimization for in vitro shoot multiplication of ... shoot length and leaf number, whereby 2 mg/L BAP alone was found to be the best with a mean shoot .... Analysis of variance showed that the interaction between.

  4. Evaluation of Different Levels of Nitrogen and Phosphorus Fertilizers on Shoot and Root Characteristics of Echinacea purpurea

    Directory of Open Access Journals (Sweden)

    morteza Goldani

    2017-09-01

    to the soil before planting and one month after transplanting seedlings and phosphorus fertilizer was added to the soil after transplanting. Results and Discussion: A difference in plant height at different levels of nitrogen was significant. By increasing the amount of nitrogen to 1 gr, plant height from 69.44 increased to 81.11 cm. Number of lateral shoots wasn’t significant in any levels of nitrogen and phosphorus. Increasing of nitrogen from 0 to 2 grams per kg of soil increased leaf weight from 2.4 to 7.5 g. However, with increasing levels of phosphorus, weight and leaf area increased. So that the treatment without phosphorus, dry weight was 4.37 grams and in 1.5 grams of phosphorus was the highest leaf dry weight with 5.77 gr. With increasing levels of nitrogen from 0 to 1 gram, shoot dry weight increased and with increasing nitrogen from 1 to 2 grams of weight shoot dry weight was low. Treatment with 1 gr of nitrogen per kilogram of soil had the highest stem dry weight per plant with 8.7 grams and showed significant differences with other treatment. Based on the results, the effect of nitrogen fertilizer treatments in the number of flowers and flower dry weight was significant at 1%, the effect of phosphorus on flower dry weight was significant. But the interaction of nitrogen and phosphorus fertilizer treatments in any levels was not significant. The highest SPAD index in1.5 gr of phosphorus and lowest (53.74 in the treatment without phosphorus was observed. Different levels of nitrogen fertilizer had not significant effect on the length and diameter of the root but a significant effect of phosphorus on root length was showed. It seems nitrogen in 1 gr per kg is related to increase photosynthesis and the growth of organs. Nitrogen with increasing in meristem cell division can increase vegetative growth and plant size. Zeinali et al (1387 reported that phosphorus can increase carbohydrates and mineral combinations in the shoots, flowers and roots. As a

  5. Nutrient and mineral composition during shoot growth in seven species of Phyllostachys and Pseudosasa bamboo consumed by giant panda.

    Science.gov (United States)

    Christian, A L; Knott, K K; Vance, C K; Falcone, J F; Bauer, L L; Fahey, G C; Willard, S; Kouba, A J

    2015-12-01

    During the annual period of bamboo shoot growth in spring, free-ranging giant pandas feed almost exclusively on the shoots while ignoring the leaves and full- height culm. Little is known about the nutritional changes that occur during bamboo shoot growth, if nutritional changes differ among species, or how these changes might influence forage selection. Our objective was to examine the nutrient and mineral composition during three phases of shoot growth (180 cm) for seven species of bamboo (Phyllostachys (P.) aurea, P. aureosulcata, P. bissetii, P. glauca, P. nuda, P. rubromarginata, Pseudosasa japonica) fed to captive giant pandas at the Memphis Zoo. Total dietary fiber content of bamboo shoots increased (p 180 cm, while crude protein, fat and ash exhibited significant declines (p panda diets when available. Journal of Animal Physiology and Animal Nutrition © 2015 Blackwell Verlag GmbH.

  6. Fresh organic matter of municipal solid waste enhances phytoextraction of heavy metals from contaminated soil

    Energy Technology Data Exchange (ETDEWEB)

    Salati, S.; Quadri, G.; Tambone, F. [Dipartimento di Produzione Vegetale, Universita degli Studi di Milano, Via Celoria 2, 20133 Milano (Italy); Adani, F., E-mail: fabrizio.adani@unimi.i [Dipartimento di Produzione Vegetale, Universita degli Studi di Milano, Via Celoria 2, 20133 Milano (Italy)

    2010-05-15

    In this study, the ability of the organic fraction of municipal solid wastes (OFMSW) to enhance heavy metal uptake of maize shoots compared with ethylenediamine disuccinic acid (EDDS) was tested on soil contaminated with heavy metals. Soils treated with OFMSW and EDDS significantly increased the concentration of heavy metals in maize shoots (increments of 302%, 66%, 184%, 169%, and 23% for Cr, Cu, Ni, Zn, and Pb with respect to the control and increments of 933%, 482%, 928%, 428%, and 5551% for soils treated with OFMSW and EDDS, respectively). In soil treated with OFMSW, metal uptake was favored because of the high presence of dissolved organic matter (DOM) (41.6x than soil control) that exhibited ligand properties because of the high presence of carboxylic acids. Because of the toxic effect of EDDS on maize plants, soil treated with OFMSW achieved the highest extraction of total heavy metals. - Organic fraction of MSW affects the bioavailability of heavy metals in soil.

  7. Fresh organic matter of municipal solid waste enhances phytoextraction of heavy metals from contaminated soil

    International Nuclear Information System (INIS)

    Salati, S.; Quadri, G.; Tambone, F.; Adani, F.

    2010-01-01

    In this study, the ability of the organic fraction of municipal solid wastes (OFMSW) to enhance heavy metal uptake of maize shoots compared with ethylenediamine disuccinic acid (EDDS) was tested on soil contaminated with heavy metals. Soils treated with OFMSW and EDDS significantly increased the concentration of heavy metals in maize shoots (increments of 302%, 66%, 184%, 169%, and 23% for Cr, Cu, Ni, Zn, and Pb with respect to the control and increments of 933%, 482%, 928%, 428%, and 5551% for soils treated with OFMSW and EDDS, respectively). In soil treated with OFMSW, metal uptake was favored because of the high presence of dissolved organic matter (DOM) (41.6x than soil control) that exhibited ligand properties because of the high presence of carboxylic acids. Because of the toxic effect of EDDS on maize plants, soil treated with OFMSW achieved the highest extraction of total heavy metals. - Organic fraction of MSW affects the bioavailability of heavy metals in soil.

  8. Micropropagation of Asparagus by in vitro shoot culture.

    Science.gov (United States)

    Stajner, Nataša

    2013-01-01

    Asparagus officinalis is most extensively studied species within the genus Asparagus, which is well known as garden asparagus. This species is dioecious with unisexual flowers, which means that generative propagation gives roughly equal number of male and female plants. Male plants are high yielders and preferred commercially over female plants. Tissue culture techniques could efficiently promote vegetative propagation of male plants and pave the way for efficient plant breeding.This chapter describes an efficient micropropagation protocol for developing rapid growing in vitro Asparagus shoot cultures. The source of explants, inoculation, and shoot proliferation, followed by shoot propagation, rooting, and acclimatization is described. The optimal medium for Asparagus micropropagation described in this chapter is composed of MS macro- and microelements and a combination of auxins and cytokinins. Plant growth regulators NAA, kinetin, and BA were used in various concentrations. Three different media representing the whole micropropagation protocol of Asparagus are described; medium for shoot initiation, medium for shoot multiplication, and medium for root formation. By in vitro propagation of Asparagus, root initiation is difficult, but can be promoted by adding growth retardant ancymidol which also greatly promotes shoot development and suppresses callus formation.

  9. Regeneration of okra ( Abelmoschus esculentus L.) via apical shoot ...

    African Journals Online (AJOL)

    Abelmoschus esculentus L. Monech) via apical shoot culture system. The study of apical shoot culture system was found effective for regeneration of apical shoots. The okra (A. esculentus L. Monech) N-550 line evolved at R&D, Nirmal Seeds Pvt. Ltd., ...

  10. Is it possible to determine firearm calibre and shooting range from the examination of gunshot residue in close range gunshot wounds? An experimental study

    Directory of Open Access Journals (Sweden)

    Anisa Gradaščević

    2013-12-01

    Full Text Available Introduction: The aim of the study was determining the type of weapon and shooting distance depending on chemical analysis of inorganic gunshot residue from the skin gunshot wounds in experimental animals (pigs.Methods: Experimental study was conducted in order to determine components and their percentage in gunshot residue (GSR. In 60 samples, pig skin was shot by fi ring projectiles from four different weapons and from three different distances (contact wound and near contact wound from 5 cm and 10 cm. The methodology included determining the presence of inorganic material: antimony, barium, lead, nickel, zinc and copper in the skin and subcutaneous tissue using atomic absorption spectrophotometry (AAS.Results: Formula for determining weapon type was provided cutt-off points for different weapons, with 78.6% of original grouped cases being correctly classifi ed. Formula for determining weapon type was provided cutt-off points for different distances, with 58.9% of original grouped cases being correctly classified, which was slightly less reliable compared to weapon type discrimination analysis.Conclusion: The presented study showed that chemical analysis of GSR in entrance wound with AAS could be useful in determining the type of weapon, as well as the shooting distance, i.e. in our study, determiningwhether the wound is contact or near contact. This could be particularly useful in postmortally putrefi ed or charred bodies with gunshot wounds.

  11. Light requirement for shoot regeneration in horseradish hairy roots.

    Science.gov (United States)

    Saitou, T; Kamada, H; Harada, H

    1992-08-01

    Hairy roots of horseradish (Armoracia rusticana) were induced by inoculation with Agrobacterium rhizogenes harboring Ri plasmid and cultured on phytohormone-free Murashige and Skoog medium after eliminating the bacteria. Hairy roots grew vigorously and sometimes formed yellowish calli under dark conditions. On the other hand, growth of hairy roots stopped after several weeks of culture with light, then shoots were regenerated. Frequency of shoot formation from hairy roots increased as the culture period in light lengthened and the light intensity increased. The shoot regeneration was induced by treatment with white or red light, but not with far-red light. Shoot regeneration by red light was inhibited by following treatment with far-red light. Red and far-red light reversibly affected shoot regeneration. Excised roots of nontransformed plants grew quite slowly on phytohormone-free Murashige and Skoog medium and occasionally formed shoots under white light conditions.

  12. Symbiotic efficiency of autochthonous arbuscular mycorrhizal fungus (G. mosseae) and Brevibacillus sp. isolated from cadmium polluted soil under increasing cadmium levels

    International Nuclear Information System (INIS)

    Vivas, A.; Voeroes, I.; Biro, B.; Campos, E.; Barea, J.M.; Azcon, R.

    2003-01-01

    Selected ubiquitous microorganisms are important components of Cd tolerance in plants. - The effect of inoculation with indigenous naturally occurring microorganisms [an arbuscular mycorrhizal (AM) fungus and rhizosphere bacteria] isolated from a Cd polluted soil was assayed on Trifolium repens growing in soil contaminated with a range of Cd. One of the bacterial isolate showed a marked PGPR effect and was identified as a Brevibacillus sp. Mycorrhizal colonization also enhanced Trifolium growth and N, P, Zn and Ni content and the dually inoculated (AM fungus plus Brevibacillus sp.) plants achieved further growth and nutrition and less Cd concentration, particularly at the highest Cd level. Increasing Cd level in the soil decreased Zn and Pb shoot accumulation. Coinoculation of Brevibacillus sp. and AM fungus increased shoot biomass over single mycorrhizal plants by 18% (at 13.6 mg Cd kg -1 ), 26% (at 33.0 mg Cd kg -1 ) and 35% (at 85.1 mg Cd kg -1 ). In contract, Cd transfer from soil to plants was substantially reduced and at the highest Cd level Brevibacillus sp. lowered this value by 37.5% in AM plants. Increasing Cd level highly reduced plant mycorrhization and nodulation. Strong positive effect of the bacterium on nodule formation was observed in all treatments. Results show that selected ubiquitous microorganisms, applied as enriched inocula, are important in plant Cd tolerance and development in Cd polluted soils

  13. Enhanced in vitro multiple shoot induction in elite Pakistani guava ...

    African Journals Online (AJOL)

    Elite guava (Psidium guajava L.) strains of cv. Safeda were explored in vitro for multiple shoot induction. Shoot induction was enhanced up to 83% with 3.5 to 4.25 shoots per single node cutting and shoot tip explants, respectively, using higher levels of benzyl amino purine (BAP) in Murashige and Skoog (MS) medium.

  14. Changes in some soil physical properties and yield of maize Grown ...

    African Journals Online (AJOL)

    Prof. Ogunji

    The declining productivity of the soils in the Abakaliki agro-ecological zone of the ... Introduction ... However, the maintenance of ... Measurements for the soil bulk density, total porosity, gravimetric moisture ... Plant height, and shoot dry weight ... LSD was calculated using Fishers least significant difference method, Steel ...

  15. Electro-kinetic remediation coupled with phytoremediation to remove lead, arsenic and cesium from contaminated paddy soil.

    Science.gov (United States)

    Mao, Xinyu; Han, Fengxiang X; Shao, Xiaohou; Guo, Kai; McComb, Jacqueline; Arslan, Zikri; Zhang, Zhanyu

    2016-03-01

    The objectives of this study were to investigate distribution and solubility of Pb, Cs and As in soils under electrokinetic field and examine the processes of coupled electrokinetic phytoremediation of polluted soils. The elevated bioavailability and bioaccumulation of Pb, As and Cs in paddy soil under an electro-kinetic field (EKF) were studied. The results show that the EKF treatment is effective on lowering soil pH to around 1.5 near the anode which is beneficial for the dissolution of metal(loid)s, thus increasing their overall solubility. The acidification in the anode soil efficiently increased the water soluble (SOL) and exchangeable (EXC) Pb, As and Cs, implying enhanced solubility and elevated overall potential bioavailability in the anode region while lower solubility in the cathode areas. Bioaccumulations of Pb, As and Cs were largely determined by the nature of elements, loading levels and EKF treatment. The native Pb in soil usually is not bioavailable. However, EKF treatment tends to transfer Pb to the SOL and EXC fractions improving the phytoextraction efficiency. Similarly, EKF transferred more EXC As and Cs to the SOL fraction significantly increasing their bioaccumulation in plant roots and shoots. Pb and As were accumulated more in plant roots than in shoots while Cs was accumulated more in shoots due to its similarity of chemical properties to potassium. Indian mustard, spinach and cabbage are good accumulators for Cs. Translocation of Pb, As and Cs from plant roots to shoots were enhanced by EKF. However, this study indicated the overall low phytoextraction efficiency of these plants. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Shoot growth of Merlot and Cabernet Sauvignon grapevine varieties

    Directory of Open Access Journals (Sweden)

    Marcelo Borghezan

    2012-02-01

    Full Text Available The objective of this work was to evaluate shoot growth of the grapevine varieties Merlot and Cabernet Sauvignon, during 2006/2007, and Cabernet Sauvignon, during 2008/2009, in São Joaquim, SC, Brazil. The experiment was carried out in a commercial vineyard trained on a vertical trellis system. The shoots of the central part of the plants were selected, and the lengths from the base to the apex of 20 shoots per cultivar were evaluated. In 2006/2007, monitoring began at pruning, on 9/15/2006, and ended on 2/6/2007, totalizing 144 days of evaluation. During the 2008/2009 cycle, phenology and shoot growth for 'Cabernet Sauvignon' were assessed from grape development (1/13/2009 (pea-sized grapes until shoot vegetative growth had ceased. Budburst occurred in the second half of September, and shoot-growth cessation occurred during ripening. Higher growth rates (about 4 cm per day were observed in pre- and post-flowering, followed by reduction due to the competition for photosynthates for the formation of flowers and bunches. Temperature and photoperiod induce grapevine shoots to cease growth in the highland regions of Santa Catarina State, Brazil.

  17. Bioremediation of gasoline contaminated soil by a bacterial consortium amended with poultry litter, coir pith and rhamnolipid biosurfactant

    International Nuclear Information System (INIS)

    Rahman, K.S.M.; Banat, I.M.; Thahira, J.; Thayumanavan, T.; Lakshmanaperumalsamy, P.

    2002-01-01

    The aim of the present study was to find methods for enhancing rates of hydrocarbon biodegradation in gasoline contaminated soil by ex situ bioremediation. Red soil (RS) was treated with gasoline-spilled soil (GS) from a gasoline station and different combinations of amendments were prepared using (i) mixed bacterial consortium (MC), (ii) poultry litter (PL), (iii) coir pith (CP) and (iv) rhamnolipid biosurfactant (BS) produced by Pseudomonas sp. DS10-129. The study was conducted for a period of 90 days during which bacterial growth, hydrocarbon degradation and growth parameters of Phaseolus aureus RoxB including seed germination, chlorophyll content, shoot and root length were measured. Approximately 67% and 78% of the hydrocarbons were effectively degraded within 60 days in soil samples amended with RS + GS + MC + PL + CP + BS at 0.1% and 1%. Maximum percentage of seed germination, shoot length, root length and chlorophyll content in P. aureus were recorded after 60 days in the above amendments. Further incubation to 90 days did not exhibit significant improvements. Statistical analysis using analysis of variance (ANOVA) and Duncan's multiple range test (DMRT) revealed that the level of amendments, incubation time and combination of amendments significantly influenced bacterial growth, hydrocarbon degradation, seed germination and chlorophyll content at a 1% probability level. All tested additives MC, PL, CP and rhamnolipid BS had significant positive effects on the bioremediation of GS. (author)

  18. Phytoextraction of soil trace elements by willow during a phytoremediation trial in Southern Québec, Canada.

    Science.gov (United States)

    Courchesne, François; Turmel, Marie-Claude; Cloutier-Hurteau, Benoît; Constantineau, Simon; Munro, Lara; Labrecque, Michel

    2017-06-03

    The phytoextraction of the trace elements (TEs) As, Cd, Cu, Ni, Pb, and Zn by willow cultivars (Fish Creek, SV1 and SX67) was measured during a 3-year field trial in a mildly contaminated soil. Biomass ranged from 2.8 to 4.4 Mg/ha/year at 30,000 plants/ha. Shoots (62%) were the main component followed by leaves (23%) and roots (15%). Biomass was positively linked to soluble soil dissolved organic carbon, K, and Mg, while TEs, not Cd and Zn, had a negative effect. The TE concentration ranking was: Zn > Cu > Cd > Ni, Pb > As, and distribution patterns were: (i) minima in shoots (As, Ni), (ii) maxima in leaves (Cd, Zn), or (iii) maxima in roots (Cu, Pb). Correlations between soil and plant TE were significant for the six TEs in roots. The amounts extracted were at a maximum for Zn, whereas Fish Creek and SV1 extracted more TE than SX67. More than 60% (91-94% for Cd and Zn) of the total TE was in the aboveground parts. Uptake increased with time because of higher biomass. Fertilization, the selection of cultivars, and the use of complementary plants are required to improve productivity and Cd and Zn uptake.

  19. Shoot and root morphogenesis from Eucalyptus grandis x urophylla ...

    African Journals Online (AJOL)

    Eucalyptus grandis x urophylla plantlets were regenerated via indirect organogenesis. Histological assessment of their development focused on identifying the calli, the differentiation of shoots from the calli and the shoot-root junction from the nascent shoots. Vascular tissue formation within the callus preceded that of ...

  20. Vanadium bioavailability in soils amended with blast furnace slag

    Energy Technology Data Exchange (ETDEWEB)

    Larsson, Maja A., E-mail: maja.larsson@slu.se [Department of Soil and Environment, Swedish University of Agricultural Sciences, P.O. Box 7014, 750 07 Uppsala (Sweden); Baken, Stijn, E-mail: stijn.baken@ees.kuleuven.be [Department of Earth and Environmental Sciences, Leuven University, Kasteelpark Arenberg 20 bus 2459, 3001 Leuven (Belgium); Smolders, Erik, E-mail: erik.smolders@ees.kuleuven.be [Department of Earth and Environmental Sciences, Leuven University, Kasteelpark Arenberg 20 bus 2459, 3001 Leuven (Belgium); Cubadda, Francesco, E-mail: francesco.cubadda@iss.it [Department of Food Safety and Veterinary Public Health, Istituto Superiore di Sanità, Viale Regina Elena 299, Rome 00161 (Italy); Gustafsson, Jon Petter, E-mail: jon-petter.gustafsson@slu.se [Department of Soil and Environment, Swedish University of Agricultural Sciences, P.O. Box 7014, 750 07 Uppsala (Sweden); Division of Land and Water Resources Engineering, KTH Royal Institute of Technology, Brinellvägen 28, 100 44 Stockholm (Sweden)

    2015-10-15

    Blast furnace (BF) slags are commonly applied as soil amendments and in road fill material. In Sweden they are also naturally high in vanadium. The aim of this study was to assess the vanadium bioavailability in BF slags when applied to soil. Two soils were amended with up to 29% BF slag (containing 800 mg V kg{sup −1}) and equilibrated outdoors for 10 months before conducting a barley shoot growth assay. Additional soil samples were spiked with dissolved vanadate(V) for which assays were conducted two weeks (freshly spiked) and 10 months (aged) after spiking. The BF slag vanadium was dominated by vanadium(III) as shown by V K-edge XANES spectroscopy. In contrast, results obtained by HPLC-ICP-MS showed that vanadium(V), the most toxic vanadium species, was predominant in the soil solution. Barley shoot growth was not affected by the BF slag additions. This was likely due to limited dissolution of vanadium from the BF slag, preventing an increase of dissolved vanadium above toxic thresholds. The difference in vanadium bioavailability among treatments was explained by the vanadium concentration in the soil solution. It was concluded that the vanadium in BF slag is sparingly available. These findings should be of importance in environmental risk assessment.

  1. Characterization of Root and Shoot Traits in Wheat Cultivars with Putative Differences in Root System Size

    Directory of Open Access Journals (Sweden)

    Victoria Figueroa-Bustos

    2018-07-01

    Full Text Available Root system size is a key trait for improving water and nitrogen uptake efficiency in wheat (Triticum aestivum L.. This study aimed (i to characterize the root system and shoot traits of five wheat cultivars with apparent differences in root system size; (ii to evaluate whether the apparent differences in root system size observed at early vegetative stages in a previous semi-hydroponic phenotyping experiment are reflected at later phenological stages in plants grown in soil using large rhizoboxes. The five wheat cultivars were grown in a glasshouse in rhizoboxes filled to 1.0 m with field soil. Phenology and shoot traits were measured and root growth and proliferation were mapped to quantify root length density (RLD, root length per plant, root biomass and specific root length (SRL. Wheat cultivars with large root systems had greater root length, more root biomass and thicker roots, particularly in the top 40 cm, than those with small root systems. Cultivars that reached anthesis later had larger root system sizes than those that reached anthesis earlier. Later anthesis allowed more time for root growth and proliferation. Cultivars with large root systems had 25% more leaf area and biomass than those with small root systems, which presumably reflects high canopy photosynthesis to supply the demand for carbon assimilates to roots. Wheat cultivars with contrasting root system sizes at the onset of tillering (Z2.1 in a semi-hydroponic phenotyping system maintained their size ranking at booting (Z4.5 when grown in soil. Phenology, particularly time to anthesis, was associated with root system size.

  2. Differential Concentrations of some Nutrient Element in Forage of Corn (Zea mays L. as Affected by Organic Fertilizers and Soil Compaction

    Directory of Open Access Journals (Sweden)

    N. Najafi

    2016-01-01

    Full Text Available Soil compaction is one of the most important limiting factor for normal crop growth, because it reduces absorption by the plant. Application of organic fertilizers in agricultural soils can reduce the detrimental effects of soil compaction on plant growth and also supply some nutrients to plant. Thus, a factorial experiment was carried out in a randomized complete block design with three replications and 14 treatments to evaluate the effects of organic fertilizers in mitigating soil compaction. The first factor in this study was the source and amount of organic fertilizer at seven levels (control, farmyard manure, sewage sludge compost and municipal solid waste compost and each of organic fertilizers at two levels of 15 and 30 g/kg of soil. The second factor was soil compaction at two levels (bulk density of 1.2 and 1.7 g/cm3. To perform this experiment, 10 kg of dry soil was poured into special PVC pots and then seeds of single cross 704 corn were planted. At the end of the growth period, the corn shoot was harvested and concentrations of phosphorus (P, potassium (K, sodium (Na, iron (Fe, zinc (Zn, manganese (Mn, cadmium (Cd and lead (Pb were determined by dry ashing method. The results showed that concentrations of Cd and Pb in the shoot, related to the different treatments, were negligible. Concentrations of P, K, Fe, Mn and Zn in the corn shoot were increased significantly by application of farmyard manure, sewage sludge compost and municipal solid waste compost at both levels of soil compaction. However, Na concentration of shoot did not change significantly. Soil compaction significantly reduced P, Fe, Mn and Zn concentrations of corn shoot, but it affected concentrations of Na and K significantly. Application of organic fertilizers and increasing their levels reduced the negative effects of soil compaction on nutrients uptake by corn plant. This study showed that to improve forage corn nutrition, application of 15 or 30 g of farmyard

  3. Nodulation by Sinorhizobium meliloti originated from a mining soil alleviates Cd toxicity and increases Cd-phytoextraction in Medicago sativa L.

    Science.gov (United States)

    Ghnaya, Tahar; Mnassri, Majda; Ghabriche, Rim; Wali, Mariem; Poschenrieder, Charlotte; Lutts, Stanley; Abdelly, Chedly

    2015-01-01

    Besides their role in nitrogen supply to the host plants as a result of symbiotic N fixation, the association between legumes and Rhizobium could be useful for the rehabilitation of metal-contaminated soils by phytoextraction. A major limitation presents the metal-sensitivity of the bacterial strains. The aim of this work was to explore the usefulness of Sinorhizobium meliloti originated from a mining site for Cd phytoextraction by Medicago sativa. Inoculated and non-inoculated plants were cultivated for 60 d on soils containing 50 and/or 100 mg Cd kg(-1) soil. The inoculation hindered the occurrence of Cd- induced toxicity symptoms that appeared in the shoots of non-inoculated plants. This positive effect of S. meliloti colonization was accompanied by an increase in biomass production and improved nutrient acquisition comparatively to non-inoculated plants. Nodulation enhanced Cd absorption by the roots and Cd translocation to the shoots. The increase of plant biomass concomitantly with the increase of Cd shoot concentration in inoculated plants led to higher potential of Cd-phytoextraction in these plants. In the presence of 50 mg Cd kg(-1) in the soil, the amounts of Cd extracted in the shoots were 58 and 178 μg plant(-1) in non-inoculated and inoculated plants, respectively. This study demonstrates that this association M. sativa-S. meliloti may be an efficient biological system to extract Cd from contaminated soils.

  4. Structure–Function Relationships in Highly Modified Shoots of Cactaceae

    Science.gov (United States)

    MAUSETH, JAMES D.

    2006-01-01

    • Background and Aims Cacti are extremely diverse structurally and ecologically, and so modified as to be intimidating to many biologists. Yet all have the same organization as most dicots, none differs fundamentally from Arabidopsis or other model plants. This review explains cactus shoot structure, discusses relationships between structure, ecology, development and evolution, and indicates areas where research on cacti is necessary to test general theories of morphogenesis. • Scope Cactus leaves are diverse; all cacti have foliage leaves; many intermediate stages in evolutionary reduction of leaves are still present; floral shoots often have large, complex leaves whereas vegetative shoots have microscopic leaves. Spines are modified bud scales, some secrete sugar as extra-floral nectaries. Many cacti have juvenile/adult phases in which the flowering adult phase (a cephalium) differs greatly from the juvenile; in some, one side of a shoot becomes adult, all other sides continue to grow as the juvenile phase. Flowers are inverted: the exterior of a cactus ‘flower’ is a hollow vegetative shoot with internodes, nodes, leaves and spines, whereas floral organs occur inside, with petals physically above stamens. Many cacti have cortical bundles vascularizing the cortex, however broad it evolves to be, thus keeping surface tissues alive. Great width results in great weight of weak parenchymatous shoots, correlated with reduced branching. Reduced numbers of shoot apices is compensated by great increases in number of meristematic cells within individual SAMs. Ribs and tubercles allow shoots to swell without tearing during wet seasons. Shoot epidermis and cortex cells live and function for decades then convert to cork cambium. Many modifications permit water storage within cactus wood itself, adjacent to vessels. PMID:16820405

  5. Structure-function relationships in highly modified shoots of cactaceae.

    Science.gov (United States)

    Mauseth, James D

    2006-11-01

    Cacti are extremely diverse structurally and ecologically, and so modified as to be intimidating to many biologists. Yet all have the same organization as most dicots, none differs fundamentally from Arabidopsis or other model plants. This review explains cactus shoot structure, discusses relationships between structure, ecology, development and evolution, and indicates areas where research on cacti is necessary to test general theories of morphogenesis. Cactus leaves are diverse; all cacti have foliage leaves; many intermediate stages in evolutionary reduction of leaves are still present; floral shoots often have large, complex leaves whereas vegetative shoots have microscopic leaves. Spines are modified bud scales, some secrete sugar as extra-floral nectaries. Many cacti have juvenile/adult phases in which the flowering adult phase (a cephalium) differs greatly from the juvenile; in some, one side of a shoot becomes adult, all other sides continue to grow as the juvenile phase. Flowers are inverted: the exterior of a cactus 'flower' is a hollow vegetative shoot with internodes, nodes, leaves and spines, whereas floral organs occur inside, with petals physically above stamens. Many cacti have cortical bundles vascularizing the cortex, however broad it evolves to be, thus keeping surface tissues alive. Great width results in great weight of weak parenchymatous shoots, correlated with reduced branching. Reduced numbers of shoot apices is compensated by great increases in number of meristematic cells within individual SAMs. Ribs and tubercles allow shoots to swell without tearing during wet seasons. Shoot epidermis and cortex cells live and function for decades then convert to cork cambium. Many modifications permit water storage within cactus wood itself, adjacent to vessels.

  6. Spine micromorphology of normal and hyperhydric Mammillaria gracilis Pfeiff. (Cactaceae) shoots.

    Science.gov (United States)

    Peharec, P; Posilović, H; Balen, B; Krsnik-Rasol, M

    2010-07-01

    Artificial conditions of tissue culture affect growth and physiology of crassulacean acid metabolism plants which often results in formation of hyperhydric shoots. In in vitro conditions Mammillaria gracilis Pfeiff. (Cactaceae) growth switches from organized to unorganized way, producing a habituated organogenic callus which simultaneously regenerates morphologically normal as well as altered hyperhydric shoots. In this study, influence of tissue culture conditions on morphology of cactus spines of normal and hyperhydric shoots was investigated. Spines of pot-grown Mammillaria plants and of in vitro regenerated shoots were examined with stereo microscope and scanning electron microscope. The pot-grown plants had 16-17 spines per areole. In vitro grown normal shoots, even though they kept typical shoot morphology, had lower number of spines (11-12) and altered spine morphology. This difference was even more pronounced in spine number (six to seven) and morphology of the hyperhydric shoots. Scanning electron microscopy analysis revealed remarkable differences in micromorphology of spine surface between pot-grown and in vitro grown shoots. Spines of in vitro grown normal shoots showed numerous long trichomes, which were more elongated on spines of the hyperhydric shoots; the corresponding structures on spine surface of pot-grown plants were noticed only as small protrusions. Scanning electron microscopy morphometric studies showed that the spines of pot-grown plants were significantly longer compared to the spines of shoots grown in tissue culture. Moreover, transverse section shape varies from elliptical in pot-grown plants to circular in normal and hyperhydric shoots grown in vitro. Cluster and correspondence analyses performed on the scanning electron microscope obtained results suggest great variability among spines of pot-grown plants. Spines of in vitro grown normal and hyperhydric shoots showed low level of morphological variation among themselves despite the

  7. Millet's Shooting Stars

    Science.gov (United States)

    Beech, M.

    1988-12-01

    In this essay two paintings by the French artist Jean-Francois Millet are described. These paintings, Les Etoiles Filantes and Nuit Etoilée are particularly interesting since they demonstrate the rare artistic employment of the shooting-star image and metaphor.

  8. Multiple shoot regeneration of cotton (Gossypium hirsutum L.) via ...

    African Journals Online (AJOL)

    user

    2011-03-14

    Mar 14, 2011 ... Induction of multiple shoots of cotton (Gossypium hirsutum L.) plant in two commercial varieties (Sahel and Varamin) using shoot apex was done. Explants were isolated from 3 - 4 days old seedlings, then they were cultured on a shoot induction media, modified MS nutrient agar with combinations: 1- ...

  9. Production of polyploids from cultured shoot tips of Eucalyptus ...

    African Journals Online (AJOL)

    Polyploids from cultured shoot tips of Eucalyptus globulus were produced by treatment with colchicine. Results showed that the combination of 0.5% colchicine and treating multiple shoot clumps for 4 days was the most appropriate conditions for E. globulus polyploidy induction and the effect of the use of multiple shoot ...

  10. Metabolic changes associated with shoot formation in tobacco callus cultures

    Energy Technology Data Exchange (ETDEWEB)

    Grady, K.L.

    1982-08-01

    Callus tissue derived from Nicotiana tabacum L. stem pith parenchyma cells was grown either on medium which maintains the callus in an undifferentiated state, or on medium which induces the formation of shoots. Two complementary types of studies were performed with the goal of establishing metabolic markers for the initiation of shoot formation: one designed to characterize the flow of radioactive sucrose into various metabolic pools, and one which allowed measurement of intermediary metabolite concentrations. In the former, callus tissue was incubated in (U-/sup 14/C)sucrose for periods up to one hour, and patterns of metabolite labelling in tissue grown on shoot-forming and non-shoot-forming media were compared. In the latter studies, tissue was grown for an entire subculture period on non-shoot-forming medium labelled with (U-/sup 14/C)sucrose, then subcultured to labelled non-shoot-forming or shoot-forming media, and sampled at intervals during the first week of growth. 189 references.

  11. Metabolic changes associated with shoot formation in tobacco callus cultures

    International Nuclear Information System (INIS)

    Grady, K.L.

    1982-08-01

    Callus tissue derived from Nicotiana tabacum L. stem pith parenchyma cells was grown either on medium which maintains the callus in an undifferentiated state, or on medium which induces the formation of shoots. Two complementary types of studies were performed with the goal of establishing metabolic markers for the initiation of shoot formation: one designed to characterize the flow of radioactive sucrose into various metabolic pools, and one which allowed measurement of intermediary metabolite concentrations. In the former, callus tissue was incubated in [U- 14 C]sucrose for periods up to one hour, and patterns of metabolite labelling in tissue grown on shoot-forming and non-shoot-forming media were compared. In the latter studies, tissue was grown for an entire subculture period on non-shoot-forming medium labelled with [U- 14 C]sucrose, then subcultured to labelled non-shoot-forming or shoot-forming media, and sampled at intervals during the first week of growth. 189 references

  12. Shooting mechanisms in Nature : A systematic review

    NARCIS (Netherlands)

    Sakes, A.; van der Wiel, M.; Henselmans, P.W.J.; van Leeuwen, J.L.; Dodou, D.; Breedveld, P.

    2016-01-01

    Background
    In nature, shooting mechanisms are used for a variety of purposes, including prey capture, defense, and reproduction. This review offers insight into the working principles of shooting mechanisms in fungi, plants, and animals in the light of the specific functional demands that these

  13. Cell fate regulation in the shoot meristem.

    Science.gov (United States)

    Laux, T; Mayer, K F

    1998-04-01

    The shoot meristem is a proliferative centre containing pluripotent stem cells that are the ultimate source of all cells and organs continuously added to the growing shoot. The progeny of the stem cells have two developmental options, either to renew the stem cell population or to leave the meristem and to differentiate, possibly according to signals from more mature tissue. The destiny of each cell depends on its position within the dynamic shoot meristem. Genetic data suggest a simple model in which graded positional information is provided by antagonistic gene functions and is interpreted by genes which regulate cell fate.

  14. Effect of in situ soil amendments on arsenic uptake in successive harvests of ryegrass (Lolium perenne cv Elka) grown in amended As-polluted soils

    International Nuclear Information System (INIS)

    Hartley, William; Lepp, Nicholas W.

    2008-01-01

    Several iron-bearing additives, selected for their potential ability to adsorb anions, were evaluated for their effectiveness in attenuation of arsenic (As) in three soils with different sources of contamination. Amendments used were lime, goethite (α-FeOOH) (crystallised iron oxide) and three iron-bearing additives, iron grit, Fe II and Fe III sulphates plus lime, applied at 1% w/w. Sequential extraction schemes conducted on amended soils determined As, Cu, Zn and Ni fractionation. Plant growth trials using perennial ryegrass (Lolium perenne var. Elka) assessed shoot As uptake. This was grown in the contaminated soils for 4 months, during which time grass shoots were successively harvested every 3 weeks. Goethite increased biomass yields, but clear differences were observed in As transfer rates with the various iron oxides. In conclusion, whilst Fe-oxides may be effective in situ amendments, reducing As bioavailability, their effects on plant growth require careful consideration. Soil-plant transfer of As was not completely halted by any amendment. - Arsenic attenuation is illustrated using Fe-based amendments, their efficacy providing different indicators of success

  15. Fresh organic matter of municipal solid waste enhances phytoextraction of heavy metals from contaminated soil.

    Science.gov (United States)

    Salati, S; Quadri, G; Tambone, F; Adani, F

    2010-05-01

    In this study, the ability of the organic fraction of municipal solid wastes (OFMSW) to enhance heavy metal uptake of maize shoots compared with ethylenediamine disuccinic acid (EDDS) was tested on soil contaminated with heavy metals. Soils treated with OFMSW and EDDS significantly increased the concentration of heavy metals in maize shoots (increments of 302%, 66%, 184%, 169%, and 23% for Cr, Cu, Ni, Zn, and Pb with respect to the control and increments of 933%, 482%, 928%, 428%, and 5551% for soils treated with OFMSW and EDDS, respectively). In soil treated with OFMSW, metal uptake was favored because of the high presence of dissolved organic matter (DOM) (41.6x than soil control) that exhibited ligand properties because of the high presence of carboxylic acids. Because of the toxic effect of EDDS on maize plants, soil treated with OFMSW achieved the highest extraction of total heavy metals. Copyright 2009 Elsevier Ltd. All rights reserved.

  16. Heavy metal uptake and leaching from polluted soil using permeable barrier in DTPA-assisted phytoextraction.

    Science.gov (United States)

    Zhao, Shulan; Shen, Zhiping; Duo, Lian

    2015-04-01

    Application of sewage sludge (SS) in agriculture is an alternative technique of disposing this waste. But unreasonable application of SS leads to excessive accumulation of heavy metals in soils. A column experiment was conducted to test the availability of heavy metals to Lolium perenne grown in SS-treated soils following diethylene triamine penta acetic acid (DTPA) application at rates of 0, 10 and 20 mmol kg(-1) soil. In order to prevent metal leaching in DTPA-assisted phytoextraction process, a horizontal permeable barrier was placed below the treated soil, and its effectiveness was also assessed. Results showed that DTPA addition significantly increased metal uptake by L. perenne shoots and metal leaching. Permeable barriers increased metal concentrations in plant shoots and effectively decreased metal leaching from the treated soil. Heavy metals in SS-treated soils could be gradually removed by harvesting L. perenne many times in 1 year and adding low dosage of DTPA days before each harvest.

  17. Contribution of root to soil respiration and carbon balance in ...

    Indian Academy of Sciences (India)

    Soil respiration varied from 2.5 to 11.9 g CO2 m-2 d-1 and from 1.5 to 9.3 g CO2 m-2 d-1, and the contribution of root respiration to total soil respiration from 38% to 76% and from 25% to 72% in Communities 1 and 2, respectively. During the growing season (May–September), soil respiration, shoot biomass, live root ...

  18. Fatal school shootings and the epidemiological context of firearm mortality in the United States.

    Science.gov (United States)

    Shultz, James M; Cohen, Alyssa M; Muschert, Glenn W; Flores de Apodaca, Roberto

    2013-01-01

    Background The December 14, 2012 mass shooting at Sandy Hook Elementary School in Newtown, Connecticut, USA, vaulted concerns regarding gun violence to the forefront of public attention. This high-visibility incident occurred within the epidemiological context of U.S. firearm mortality that claims more than 88 lives daily. Methods National epidemiologic data on firearm deaths over two decades were analyzed along with data registries on school shootings in order to place the tragedy at Sandy Hook in perspective. School shootings were classified as random or targeted. Results The U.S. has the highest rates of firearm deaths, suicides, and homicides among the world's 34 "advanced economies." Seventy percent of U.S. homicides and more than 50% of U.S. suicides are committed using a firearm. U.S. firearm homicide rates first declined, and then stabilized, during the past 23 years, 1990-2012. "Shooting massacres" in school settings, a new phenomenon within the past 50 years, are extremely rare events. Over 23 years, 1990-2012, 215 fatal school shooting incidents resulted in 363 deaths, equivalent to 0.12% of national firearm homicides during that time period. Most episodes were "targeted" shootings in which the perpetrator intentionally killed a specific individual in a school setting. Only 25 of these 215 events (11.6%) were "random" or "rampage" shootings, resulting in 135 deaths (0.04% of national firearm homicides). Among these, just three shooting rampages - Columbine High School, Virginia Tech University, and Sandy hook Elementary School - accounted for 72 (53.3%) of these 135 deaths. The frequency of random/rampage shooting incidents in schools has remained within the narrow range of 0 to 3 episodes per year. Conclusions Each year, more than 32,000 Americans die by firearms and more than 70,000 are wounded, representing a volume of preventable deaths and injuries that the U.S. government describes as a "public health crisis." School massacres, such as Sandy Hook

  19. Accuracy of Skill Performance in the Basketball Free Throw Shooting

    Directory of Open Access Journals (Sweden)

    Igawa Shoji

    2011-12-01

    Full Text Available The purpose of this study were to investigates how timing of shot of skilled player and assess performance accuracy of free throw shooting. Ten college students participated in this study (5 skilled players, and 5 naïve participants aged 18-23 years. They performed free throw shooting at 10 times. Shooting seen was recorded three cameras and analyzed shooting successful rate, off-target distance (the distance between the basketball through point and the center of the goal and shot timing. Shot timing was not significant difference. Shooting successful rate of skilled players was higher than unskilled players. Offtarget distance of skilled players was significant smaller than naive player. Consequently, skilled player is possible to aim at the center of the goal and shooting near the center of goal.

  20. Heating treatment schemes for enhancing chelant-assisted phytoextraction of heavy metals from contaminated soils.

    Science.gov (United States)

    Chen, Yahua; Wang, Chunchun; Wang, Guiping; Luo, Chunling; Mao, Ying; Shen, Zhenguo; Li, Xiangdong

    2008-04-01

    Recent research has shown that chelant-assisted phytoextraction approaches often require a high dosage of chelant applied to soil. The present study focused on optimization of phytoremediation processes to increase the phytoextraction efficiency of metals at reduced chelant applications. Pot experiments were carried out to investigate the effects of increased soil temperature on shoot uptake of heavy metals by corn (Zea mays L.) and mung bean (Vigna radiat L. Wilczek) from heavy metal-contaminated soils. After the application of S,S-ethylenediaminedisuccinic acid or ethylenediaminetetra-acetic acid, soils were exposed to high temperatures (50 or 80 degrees C) for 3 h, which significantly increased the concentration of heavy metals in shoots. The heating treatment 2 d after the chelant addition resulted in higher concentrations of metals compared with those treatments 2 d before or simultaneously with the chelant application. Irrigation with 100 degrees C water 2 d after the chelant addition, or irrigation with 100 degrees C chelant solutions directly, also resulted in significantly higher phytoextraction of metals in the two crops compared with 25 degrees C chelant solutions. In addition, a novel application method to increase soil temperature using underground polyvinyl chloride tubes would increase the chelant-assisted extraction efficiency of Cu approximately 10- to 14-fold in corn and fivefold in mung bean compared with those nonheating treatments. In a field experiment, increasing soil temperature 2 d after chelant addition also increased the shoot Cu uptake approximately fivefold compared with those nonheating treatments. This new technique may represent a potential, engineering-oriented approach for phytoremediation of metal-polluted soils.

  1. Effect of zinc fertilization on cadmium toxicity in durum and bread wheat grown in zinc-deficient soil

    International Nuclear Information System (INIS)

    Koeleli, Nurcan; Eker, Selim; Cakmak, Ismail

    2004-01-01

    The effect of increasing application of zinc (Zn) and cadmium (Cd) on shoot dry weight and shoot concentrations of Zn and Cd was studied in bread and durum wheat cultivars. Plants were grown in severely Zn-deficient calcareous soil treated with increasing Zn (0 and 10 mg kg -1 soil) and Cd (0, 10 and 25 mg kg -1 soil) and harvested after 35 and 65 days of growth under greenhouse conditions. Growing plants without Zn fertilization caused severe depression in shoot growth, especially in durum wheat and at high Cd treatment. Cadmium treatments resulted in rapid development of necrotic patches on the base and sheath parts of the oldest leaves of both wheat cultivars, but symptoms were more severe in durum wheat and under Zn deficiency. Decreases in shoot dry weight from increasing Cd application were more severe in Zn-deficient plants. Severity of Cd toxicity symptoms in durum and bread wheat at different Zn treatments did not show any relation to the Cd concentrations in shoot. Increasing Cd application to Zn-deficient plants tended to decrease Zn concentrations in Zn-deficient plants, whereas in plants with adequate Zn, concentrations of Zn were either not affected or increased by Cd. The results show that durum wheat was more sensitive to both Zn deficiency and Cd toxicity as compared to bread wheat. Cadmium toxicity in the shoot was alleviated by Zn treatment, but this was not accompanied by a corresponding decrease in shoot concentrations of Cd. Our results are compatible with the hypothesis that Zn protects plants from Cd toxicity by improving plant defense against Cd-induced oxidative stress and by competing with Cd for binding to critical cell constituents such as enzymes and membrane protein and lipids

  2. Journalism and School Shootings in Finland 2007 -2008

    OpenAIRE

    Raittila, Pentti; Koljonen, Kari; Väliverronen, Jari

    2010-01-01

    Two school shootings in Finland (Jokela in 2007 and Kauhajoki in 2008) resulted in the death of 20 people, and they shook not only the foundations of Finnish society but also of the profession that reported about the tragedies. This report is based on research conducted on school shootings at the University of Tampere Journalism Research and Development Centre between 2008 and 2009. The analysis concentrates on both the journalistic texts published on the shootings and journalists' actions...

  3. Effects of lead and chelators on growth, photosynthetic activity and Pb uptake in Sesbania drummondii grown in soil

    International Nuclear Information System (INIS)

    Ruley, Adam T.; Sharma, Nilesh C.; Sahi, Shivendra V.; Singh, Shree R.; Sajwan, Kenneth S.

    2006-01-01

    Effects of lead (Pb) and chelators, such as EDTA, HEDTA, DTPA, NTA and citric acid, were studied to evaluate the growth potential of Sesbania drummondii in soils contaminated with high concentrations of Pb. S. drummondii seedlings were grown in soil containing 7.5 g Pb(NO 3 ) 2 and 0-10 mmol chelators/kg soil for a period of 2 and 4 weeks and assessed for growth profile (length of root and shoot), chlorophyll a fluorescence kinetics (F v /F m and F v /F o ) and Pb accumulations in root and shoot. Growth of plants in the presence of Pb + chelators was significantly higher (P v /F m and F v /F o values of treated seedlings remained unaffected, indicating normal photosynthetic efficiency and strength of plants in the presence of chelators. On application of chelators, while root uptake of Pb increased four-five folds, shoot accumulations increased up to 40-folds as compared to controls (Pb only) depending on the type of chelator used. Shoot accumulations of Pb varied from 0.1 to 0.42% (dry weight) depending on the concentration of chelators used. - Sesbania drummondii tolerates and accumulates high concentrations of Pb

  4. Defense.gov Special Report: Fort Hood Shooting

    Science.gov (United States)

    identify possible insider threats, Army Secretary John M. McHugh told lawmakers. Story Obama: Soldiers ," Army Secretary John M. McHugh told lawmakers. Story President Praises Swift Response to Fort Hood Remarks on Fort Hood Shooting at White House McHugh, Odierno Address Fort Hood Shooting Before Congress

  5. Contagion in Mass Killings and School Shootings.

    Directory of Open Access Journals (Sweden)

    Sherry Towers

    Full Text Available Several past studies have found that media reports of suicides and homicides appear to subsequently increase the incidence of similar events in the community, apparently due to the coverage planting the seeds of ideation in at-risk individuals to commit similar acts.Here we explore whether or not contagion is evident in more high-profile incidents, such as school shootings and mass killings (incidents with four or more people killed. We fit a contagion model to recent data sets related to such incidents in the US, with terms that take into account the fact that a school shooting or mass murder may temporarily increase the probability of a similar event in the immediate future, by assuming an exponential decay in contagiousness after an event.We find significant evidence that mass killings involving firearms are incented by similar events in the immediate past. On average, this temporary increase in probability lasts 13 days, and each incident incites at least 0.30 new incidents (p = 0.0015. We also find significant evidence of contagion in school shootings, for which an incident is contagious for an average of 13 days, and incites an average of at least 0.22 new incidents (p = 0.0001. All p-values are assessed based on a likelihood ratio test comparing the likelihood of a contagion model to that of a null model with no contagion. On average, mass killings involving firearms occur approximately every two weeks in the US, while school shootings occur on average monthly. We find that state prevalence of firearm ownership is significantly associated with the state incidence of mass killings with firearms, school shootings, and mass shootings.

  6. Contagion in Mass Killings and School Shootings.

    Science.gov (United States)

    Towers, Sherry; Gomez-Lievano, Andres; Khan, Maryam; Mubayi, Anuj; Castillo-Chavez, Carlos

    2015-01-01

    Several past studies have found that media reports of suicides and homicides appear to subsequently increase the incidence of similar events in the community, apparently due to the coverage planting the seeds of ideation in at-risk individuals to commit similar acts. Here we explore whether or not contagion is evident in more high-profile incidents, such as school shootings and mass killings (incidents with four or more people killed). We fit a contagion model to recent data sets related to such incidents in the US, with terms that take into account the fact that a school shooting or mass murder may temporarily increase the probability of a similar event in the immediate future, by assuming an exponential decay in contagiousness after an event. We find significant evidence that mass killings involving firearms are incented by similar events in the immediate past. On average, this temporary increase in probability lasts 13 days, and each incident incites at least 0.30 new incidents (p = 0.0015). We also find significant evidence of contagion in school shootings, for which an incident is contagious for an average of 13 days, and incites an average of at least 0.22 new incidents (p = 0.0001). All p-values are assessed based on a likelihood ratio test comparing the likelihood of a contagion model to that of a null model with no contagion. On average, mass killings involving firearms occur approximately every two weeks in the US, while school shootings occur on average monthly. We find that state prevalence of firearm ownership is significantly associated with the state incidence of mass killings with firearms, school shootings, and mass shootings.

  7. Comparative evaluation of phytoremediation of metal contaminated soil of firing range by four different plant species

    Directory of Open Access Journals (Sweden)

    Saadia R. Tariq

    2016-11-01

    Full Text Available The phytoremediation potential of Helianthus annuus, Zea maize, Brassica campestris and Pisum sativum was studied for the soil of firing range contaminated with selected metals i.e. Cd, Cu, Co, Ni, Cr and Pb. The seedlings of the selected plants germinated in a mixture of sand and alluvial soil were transferred to the pots containing the soil of firing ranges and allowed to grow to the stage of reproductive growth. Subsequently they were harvested and then analyzed for selected metals by using AAS. Among the studied plants, P. sativum exhibited highest removal efficiency (i.e. 96.23% and bioconcentration factor for Pb thereby evidencing it to be Pb hyperaccumulator from the soil of firing ranges. Z. maize appreciably reduced the levels of all the selected metals in the soil but the highest phytoextraction capacity was shown for Pb i.e. 66.36%, which was enhanced to approximately 74% on EDTA application. H. annuus represented the highest removal potential for Cd i.e. 56.03% which was further increased on EDTA application. Thus it proved to be an accumulator of Cd after EDTA application. It was therefore concluded that different plants possess different phytoremediation potentials under given set of conditions.

  8. The effect of triacontanol on shoot multiplication and production of antioxidant compounds in shoot cultures of Salvia officinalis L.

    Directory of Open Access Journals (Sweden)

    Izabela Grzegorczyk

    2011-01-01

    Full Text Available This report describes the effect of triacontanol on shoot multiplication and production of antioxidant compounds (carnosic acid, carnosol and rosmarinic acid in S. officinalis cultures grown on MS basal medium (agar solidified medium supplemented with 0.1 mg l-1 IAA, 0.45 mg l-1 BAP. It was found that shoot proliferation significantly increased when triacontanol at concentrations of 5, 10 or 20 µg l-1 was added to the medium. HPLC analysis of acetone and methanolic extracts of sage shoots showed that the production of diterpenoids, carnosic acid/carnosol ratio, as well as, contents of rosmarinic acid were also affected by the treatment with triacontanol. The highest stimulation effect of triacontanol was observed on the production of carnosol, where the treatment with 20 µg l l-1 increased the content of this diterpenoid 4.5-fold compared to that in the control (sage shoots growing on MS basal medium, only.

  9. Evaluating phytoextraction efficiency of two high-biomass crops after soil amendment and inoculation with rhizobacterial strains.

    Science.gov (United States)

    Vanessa, Álvarez-López; Ángeles, Prieto-Fernández; Sergio, Roiloa; Beatriz, Rodríguez-Garrido; Rolf, Herzig; Markus, Puschenreiter; Susan, Kidd Petra

    2017-03-01

    We evaluated the effect of compost amendment and/or bacterial inoculants on the growth and metal accumulation of Salix caprea (clone BOKU 01 AT-004) and Nicotiana tabacum (in vitro-bred clone NBCu10-8). Soil was collected from an abandoned Pb/Zn mine and rhizobacterial inoculants were previously isolated from plants growing at the same site. Plants were grown in untreated or compost-amended (5% w/w) soil and were inoculated with five rhizobacterial strains. Non-inoculated plants were also established as a control. Compost addition increased the shoot DW yield of N. tabacum but not S. caprea, while it decreased soil metal availability and lowered shoot Cd/Zn concentrations in tobacco plants. Compost amendment enhanced the shoot Cd/Zn removal due to the growth promotion of N. tabacum or to the increase in metal concentration in S. caprea leaves. Bacterial inoculants increased photosynthetic efficiency (particularly in N. tabacum) and sometimes modified soil metal availability, but this did not lead to a significant increase in Cd/Zn removal. Compost amendment was more effective in improving the Cd and Zn phytoextraction efficiency than bioaugmentation.

  10. Australian Mass Shootings: An Analysis of Incidents and Offenders.

    Science.gov (United States)

    McPhedran, Samara

    2017-06-01

    Mass shooting events are relatively underresearched, and most study comes from the United States. Despite significant international interest, little is known about other countries' experiences of these events. The current study examines Australian mass shooting incidents and offenders, with emphasis on mental illness, life strains, and offenders' life histories. Australia had 14 mass shootings between 1964 and 2014. Most offenders experienced acute life stressors and/or chronic strains leading up to the event; however, diagnosed mental illness was less commonly documented. These observations provide new information about mass shooting incidents and offenders, and can help to inform international policy development.

  11. Influence of iron plaque on uptake and accumulation of Cd by rice (Oryza sativa L.) seedlings grown in soil.

    Science.gov (United States)

    Liu, Houjun; Zhang, Junling; Christie, Peter; Zhang, Fusuo

    2008-05-15

    Iron plaque is ubiquitously formed on the root surfaces of rice. However, little is known about the role of iron plaque in Cd movement from soil to the plant aboveground parts. A pot experiment was conducted to investigate the influence of iron plaque in Cd uptake and accumulation by rice seedlings in soil. Rice seedlings were pre-cultivated in solution culture for 16 days. Two seedlings were transplanted in a nylon bag containing no substrate but surrounded by soil amended with Fe and Cd combined at rates of 0, 1, or 2 g Fe kg(-1) and 0, 2.0, or 10 mg Cd kg(-1) soil. Fe was added to induce different amounts of iron plaque, and Cd to simulate Cd-polluted soils. Plants were grown for a further 43 days and then harvested. The length of the longest leaf and SPAD values of the newly mature leaves were measured during plant growth. Fe and Cd concentrations were determined in dithionite-citrate-bicarbonate (DCB) soil extracts and in plant roots and shoots. Shoot and root dry weights were significantly affected by Fe supply level but not by added Cd. Root dry weight declined with increasing Fe supply but shoot dry weight decreased at 2 g Fe kg(-1) and increased at 1 g Fe kg(-1) (except at 2 mg Cd kg(-1)). The length of the longest leaf and SPAD values of the newly mature leaves were significantly affected by plant growth stage and added Fe and Cd. Fe tended to diminish the negative effect of Cd on these two parameters. Cd concentrations in DCB extracts increased with increasing Cd and Fe supply. In contrast, external Fe supply markedly reduced shoot and root Cd concentrations and there was generally no significant difference between the two Fe supply levels. Shoot and root Cd concentrations increased with increasing Cd addition. Root Cd concentrations were negatively correlated with root Fe concentrations. The proportion of Cd in DCB extracts was significantly lower than in roots or shoots. The results indicate that enhanced Fe uptake by plants can diminish the negative

  12. Phyto stabilization of cadmium contaminated soils by Lupinus uncinatus Schldl

    International Nuclear Information System (INIS)

    Ehsan, M.; Santamaria-Delgado, K.; Vazquez-Alarcon, A.; Alderete-Chavez, A.; Cruz de la, N.; Jaen-Contreras, D.; Augustine Molumeli, P.

    2009-01-01

    Phyto remediation offers the benefits of being in situ, low cost and environmentally sustainable. Lupinus species is starting to generate interest for phyto remediation of soils showing intermediate metal pollution. The aim of this study was to explore the accumulating behavior and tolerance of Lupinus uncessant Schldl. towards increasing Cd concentrations in soil. For this purpose the effects of different Cd treatments on plant growth, survival, metal tolerance, Cd accumulation and distribution in various plant organs were investigated. An 18 week pot trial was performed under greenhouse conditions. Cd was added as CdCl 2 .2 1 /2H 2 O at the rate of 0, 3, 6 and 9 mg Cd kg - 1 soil at three different occasions (after 4th, 12th and 15th week of plant growth) with four replicates. The Cd treatments applied, thus, were 9, 18 and 27 mg kg - 1. Cd inhibited plant height and number of leaves and induced a significant change in dry matter yield of roots, stems and leaves. Metal tolerance indices of 88, 82 and 49% were obtained for 9, 18 and 27 mg Cd kg - 1 treatments. The maximal shoot Cd concentration (stem+leaves) of 540 mg Cd kg - 1 dry matter was found at 27 mg Cd kg - 1 treatment. The poor translocation of Cd from roots to shoot was evident from shoot:root ratios <1. The present work is the first report about the growth performance of L. uncinatus under Cd stress, its degree of tolerance and pattern of Cd accumulation in response to varying Cd treatments in soil suggesting the use of L. uncinatus for phyto stabilization and revegetation of Cd polluted soils. (Author)

  13. Shooting stars

    International Nuclear Information System (INIS)

    Maurette, M.; Hammer, C.

    1985-01-01

    A shooting star passage -even a star shower- can be sometimes easily seen during moonless black night. They represent the partial volatilization in earth atmosphere of meteorites or micrometeorites reduced in cosmic dusts. Everywhere on earth, these star dusts are searched to be gathered. This research made one year ago on the Greenland ice-cap is this article object; orbit gathering projects are also presented [fr

  14. Zinc-arsenic interactions in soil: Solubility, toxicity and uptake.

    Science.gov (United States)

    Kader, Mohammed; Lamb, Dane T; Wang, Liang; Megharaj, Mallavarapu; Naidu, Ravi

    2017-11-01

    Arsenic (As) and zinc (Zn) are common co-contaminants in mining impacted soils. Their interaction on solubility and toxicity when present concurrently is not well understood in natural systems. The aim of this study was to observe their interaction in solubility (soil-solution), bioaccumulation (shoot uptake) and toxicity to cucumber (Cucumis sativa L) conducting 4 weeks pot study in 5 different soils spiked with As (0, 2, 4, 8 to 1024 mg kg -1 ) individually and with Zn at two phytotoxic doses. The As pore-water concentration was significantly reduced (df = 289, Adjusted R 2  = 0.84, p soils. This outcome may be due to adsorption/surface precipitation or tertiary bridging complexation. No homogenous precipitation of zinc arsenate could be established using electron microscopy, XRD or even equilibrium calculations. For bioaccumulation phase, no significant effect of Zn on As uptake was observed except acidic MG soil whereas, Zn uptake was significantly reduced (p soil. The synergistic response (more than additive) was predominant in this soil for a wide range of inhibition concentration (0-80%) at both Zn EC10 and EC50 levels. Since additive response is mostly considered in risk assessment for mixtures, precautions should be implemented for assessment of toxicity for As-Zn mixture in acidic soil due to their synergistic response in some soils. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. thidiazuron improves adventitious bud and shoot regeneration

    African Journals Online (AJOL)

    Prof. Adipala Ekwamu

    Induction of adventitious buds and shoots from intact leaves and stem internode segments of two recalcitrant. Ugandan sweetpotato (Ipomoea batatas L.) cultivars was investigated in vitro on Murashige and Skoog (MS) medium, supplemented with 3 different levels (0.5, 2.0 and 4.0 µM) of Thidiazuron (TDZ). Shoots were.

  16. School shootings during 2013-2015 in the USA.

    Science.gov (United States)

    Kalesan, Bindu; Lagast, Kinan; Villarreal, Marcos; Pino, Elizabeth; Fagan, Jeffrey; Galea, Sandro

    2017-10-01

    Data on the factors associated with school shootings in the USA are limited. The public conversation has often suggested several factors that may be linked to these events, however with little empirical support. Aiming to fill this gap, we describe the characteristics of school shooting incidents in the USA between 2013 and 2015 and explore whether four factors that represent domains of firearm policy, educational policy and epidemiological risk factors for intentional firearm injuries-background check (BC) policies, per capita mental health expenditures (MHE), K-12 education expenditure (KEE) and urbanicity-were associated with school shootings during this period. We searched LexisNexis, a newspaper and broadcast media databases for school shooting incidents from 1 January 2013 to 31 December 2015. Presence of BC laws was extracted from legal information in LexisNexis. State-level covariates of per capita MHE (2013), KEE (2013) and urbanicity (2010) rates were obtained from publicly available data sources. We used negative binomial regression models accounting for clustering by state to explore unadjusted associations between the BC laws, state-level covariates and school shootings to report IRR and 95% CI. We documented 154 school shootings (35, 55 and 64 each year). In unadjusted models, BC for firearm purchase (IRR=0.55, 95% CI 0.39 to 0.76), ammunition purchase (IRR=0.11, 95% CI 0.05 to 0.27), log per capita MHE (IRR=0.58, 95% CI 0.37 to 0.90), log per-capita KEE (IRR=0.09, 9% CI 0.02 to 0.29) and urbanicity (IRR=0.97, 95% CI 0.96 to 0.99) were associated with school shooting. School shootings are less likely in states with BC laws, higher MHE and KEE, and with greater per cent urban population. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  17. The Mental Health Consequences of Mass Shootings.

    Science.gov (United States)

    Lowe, Sarah R; Galea, Sandro

    2017-01-01

    Mass shooting episodes have increased over recent decades and received substantial media coverage. Despite the potentially widespread and increasing mental health impact of mass shootings, no efforts to our knowledge have been made to review the empirical literature on this topic. We identified 49 peer-reviewed articles, comprised of 27 independent samples in the aftermath of 15 mass shooting incidents. Based on our review, we concluded that mass shootings are associated with a variety of adverse psychological outcomes in survivors and members of affected communities. Less is known about the psychological effects of mass shootings on indirectly exposed populations; however, there is evidence that such events lead to at least short-term increases in fears and declines in perceived safety. A variety of risk factors for adverse psychological outcomes have been identified, including demographic and pre-incident characteristics (e.g., female gender and pre-incident psychological symptoms), event exposure (e.g., greater proximity to the attack and acquaintance with the deceased), and fewer psychosocial resources (e.g., emotion regulation difficulties and lower social support). Further research that draws on pre-incident and longitudinal data will yield important insights into the processes that exacerbate or sustain post-incident psychological symptoms over time and provide important information for crisis preparedness and post-incident mental health interventions. © The Author(s) 2015.

  18. Chemical stabilization of cadmium in acidic soil using alkaline agronomic and industrial by-products.

    Science.gov (United States)

    Chang, Yao-Tsung; Hsi, Hsing-Cheng; Hseu, Zeng-Yei; Jheng, Shao-Liang

    2013-01-01

    In situ immobilization of heavy metals using reactive or stabilizing materials is a promising solution for soil remediation. Therefore, four agronomic and industrial by-products [wood biochar (WB), crushed oyster shell (OS), blast furnace slag (BFS), and fluidized-bed crystallized calcium (FBCC)] and CaCO3 were added to acidic soil (Cd = 8.71 mg kg(-1)) at the rates of 1%, 2%, and 4% and incubated for 90 d. Chinese cabbage (Brassica chinensis L.) was then planted in the soil to test the Cd uptake. The elevation in soil pH caused by adding the by-products produced a negative charge on the soil surface, which enhanced Cd adsorption. Consequently, the diethylenetriamine pentaacetic acid (DTPA)-extractable Cd content decreased significantly (P soil. These results from the sequential extraction procedure indicated that Cd converted from the exchangeable fraction to the carbonate or Fe-Mn oxide fraction. The long-term effectiveness of Cd immobilization caused by applying the 4 by-products was much greater than that caused by applying CaCO3. Plant shoot biomass clearly increased because of the by-product soil amendment. Cd concentration in the shoots was soil.

  19. Increased P diffusion as an explanation of increased P availability in flooded rice soils

    International Nuclear Information System (INIS)

    Turner, F.T.; Gilliam, J.W.

    1976-01-01

    Phosphorus supply factors (capacity, kinetic, intensity, and diffusivity) and plant growth were the approaches used to assess P supply of flooded rice soils. Increases in the capacity, intensity and kinetic factors, as measured by E-value, solution P concentration, and soil P release rate to a distilled water 'sink' respectively, were unpronounced and infrequent upon water-saturation of ten soils. However, increases in the diffusivity factor, as measured by 32 P diffusion coefficients, were at least ten-fold as soil moisture increased. The greatest increases in P diffusion occurred as soil moisture increased beyond one-third bar. Using a P-fertilized soil or P treated powdered cellulose as the P source and a minus P nutrient solution to nourish a split root system with water and nutrients, data were obtained which suggested that P uptake and rice shoot growth (indicators of P availability) increased with increasing moisture level. Phosphorus uptake and rice-shoot growth were greatest when the soil or P treated cellulose were water-saturated. These data indicate that increased soil P availability upon flooding can be attributed to an increase in the diffusivity factor

  20. Mass Shootings: The Role of the Media in Promoting Generalized Imitation.

    Science.gov (United States)

    Meindl, James N; Ivy, Jonathan W

    2017-03-01

    Mass shootings are a particular problem in the United States, with one mass shooting occurring approximately every 12.5 days. Recently a "contagion" effect has been suggested wherein the occurrence of one mass shooting increases the likelihood of another mass shooting occurring in the near future. Although contagion is a convenient metaphor used to describe the temporal spread of a behavior, it does not explain how the behavior spreads. Generalized imitation is proposed as a better model to explain how one person's behavior can influence another person to engage in similar behavior. Here we provide an overview of generalized imitation and discuss how the way in which the media report a mass shooting can increase the likelihood of another shooting event. Also, we propose media reporting guidelines to minimize imitation and further decrease the likelihood of a mass shooting.

  1. Light Requirement for Shoot Regeneration in Horseradish Hairy Roots 1

    Science.gov (United States)

    Saitou, Tsutomu; Kamada, Hiroshi; Harada, Hiroshi

    1992-01-01

    Hairy roots of horseradish (Armoracia rusticana) were induced by inoculation with Agrobacterium rhizogenes harboring Ri plasmid and cultured on phytohormone-free Murashige and Skoog medium after eliminating the bacteria. Hairy roots grew vigorously and sometimes formed yellowish calli under dark conditions. On the other hand, growth of hairy roots stopped after several weeks of culture with light, then shoots were regenerated. Frequency of shoot formation from hairy roots increased as the culture period in light lengthened and the light intensity increased. The shoot regeneration was induced by treatment with white or red light, but not with far-red light. Shoot regeneration by red light was inhibited by following treatment with far-red light. Red and far-red light reversibly affected shoot regeneration. Excised roots of nontransformed plants grew quite slowly on phytohormone-free Murashige and Skoog medium and occasionally formed shoots under white light conditions. PMID:16669041

  2. Repeated phytoextraction of four metal-contaminated soils using the cadmium/zinc hyperaccumulator Sedum plumbizincicola

    International Nuclear Information System (INIS)

    Li, Zhu; Wu, Longhua; Hu, Pengjie; Luo, Yongming; Zhang, Hao; Christie, Peter

    2014-01-01

    A cadmium/zinc hyperaccumulator extracted metals from four contaminated soils over three years in a glasshouse experiment. Changes in plant metal uptake and soil total (aqua regia-extractable) and available metals were investigated. Plant Cd concentrations in a high-Cd acid soil and plant Zn concentrations in two acid soils decreased during repeated phytoextraction and were predicted by soil available metal concentrations. However, on repeated phytoextraction, plant Cd concentrations remained constant in lightly Cd-polluted acid soils, as did plant Cd and Zn in alkaline soils, although soil available metal concentrations decreased markedly. After phytoextraction acid soils showed much higher total metal removal efficiencies, indicating possible suitability of phytoextraction for acid soils. However, DGT-testing, which takes soil metal re-supply into consideration, showed substantial removal of available metal and distinct decreases in metal supply capacity in alkaline soils after phytoextraction, suggesting that a strategy based on lowering the bioavailable contaminant might be feasible. - Highlights: • Plant shoot Cd decreased in high-Cd acid soil and also plant Zn did in two acid soils. • Plant shoot Cd remained constant in low-Cd acid soil and also plant Zn did in alkaline soils. • Acidic soils showed much higher total metal removal efficiency than the alkaline soils. - Acid soil has high total metal phytoremediation efficiency while a strategy based on stripping of the bioavailable contaminant might be feasible for alkaline soil phytoremediation

  3. Plants influence on arsenic availability and speciation in the rhizosphere, roots and shoots of three different vegetables

    International Nuclear Information System (INIS)

    Bergqvist, Claes; Herbert, Roger; Persson, Ingmar; Greger, Maria

    2014-01-01

    The toxicity of arsenic (As) in the environment is controlled by its concentration, availability and speciation. The aims of the study were to evaluate the accumulation and speciation of As in carrot, lettuce and spinach cultivated in soils with various As concentrations and to estimate the concomitant health risks associated with the consumption of the vegetables. Arsenic concentration and speciation in plant tissues and soils was analysed by HPLC, AAS and XANES spectroscopy. To estimate the plants influence in the rhizosphere, organic acids in lettuce root exudates were analysed by ion chromatography. The results showed that the As accumulation was higher in plants cultivated in soil with higher As extractability. Arsenate predominated in the soils, rhizosphere and root exudates of lettuce. Succinic acid was the major organic acid in lettuce root exudates. Ingestion of the tested vegetables may result in an intake of elevated levels of inorganic As. -- Highlights: • In soils with higher arsenic extractability, accumulation in plants was higher. • Arsenate predominated in the soils, rhizosphere and root exudates of lettuce. • Arsenite predominated in the shoots of healthy looking vegetables. -- Regardless of the initial level of extractable As in the soil, the plants almost doubled the extractable As in the rhizosphere soil

  4. African Journal of Range and Forage Science - Vol 11, No 1 (1976)

    African Journals Online (AJOL)

    African Journal of Range and Forage Science. ... Changes of biomass in some perennial grass species. ... The use of shoot dimensions to estimate the leaf mass or shoot area of certain indigenous ... Italian ryegrass as a perennial fodder crop.

  5. Effects of calcium gluconate and ascorbic acid on controlling shoot ...

    African Journals Online (AJOL)

    In vitro shoot necrosis is a quite widespread disorder affecting raspberry micropropagation. This study was conducted to investigate effects of calcium gluconate and ascorbic acid on shoot necrosis and dieback of raspberry shoots during micropropagation. Nodal segments of primocane-fruiting raspberry cultivars 'Allgold', ...

  6. Tragedy and the Meaning of School Shootings

    Science.gov (United States)

    Warnick, Bryan R.; Johnson, Benjamin A.; Rocha, Samuel

    2010-01-01

    School shootings are traumatic events that cause a community to question itself, its values, and its educational systems. In this article Bryan Warnick, Benjamin Johnson, and Samuel Rocha explore the meanings of school shootings by examining three recent books on school violence. Topics that grow out of these books include (1) how school shootings…

  7. Distributed trouble-shooting

    NARCIS (Netherlands)

    Post, W.M.; Bogaard, S.A.A. van den; Rasker, P.C.

    2004-01-01

    When knowledge, required for trouble-shooting at sea, can be supplied real-time but from a distance, problems, such as with the limited availability of specialists, and the high costs of maintenance, may be tackled. Unclear is, however, how this redistribution of knowledge will work in practice. We

  8. Arsenic contamination of soils and agricultural plants through irrigation water in Nepal

    Energy Technology Data Exchange (ETDEWEB)

    Dahal, B.M. [Institute of Soil Research, University of Natural Resources and Applied Life Sciences (BOKU), Peter Jordan Strasse 82, A-1190 Vienna (Austria); Institute of Sanitary Engineering and Water Pollution Control, University of Natural Resources and Applied Life Sciences (BOKU), Muthgasse 18, A-1190 Vienna (Austria); Environment and Public Health Organization (ENPHO), P.O. Box 4102, Kathmandu (Nepal); Fuerhacker, M. [Institute of Sanitary Engineering and Water Pollution Control, University of Natural Resources and Applied Life Sciences (BOKU), Muthgasse 18, A-1190 Vienna (Austria); Mentler, A. [Institute of Soil Research, University of Natural Resources and Applied Life Sciences (BOKU), Peter Jordan Strasse 82, A-1190 Vienna (Austria); Karki, K.B. [Soil Science Division, Nepal Agricultural Research Council, Khumaltar, Lalitpur (Nepal); Shrestha, R.R. [UN Habitat-Nepal, UN House, Pulchwok, P.O. Box 107, Kathmandu (Nepal); Blum, W.E.H. [Institute of Soil Research, University of Natural Resources and Applied Life Sciences (BOKU), Peter Jordan Strasse 82, A-1190 Vienna (Austria)], E-mail: winfried.blum@boku.ac.at

    2008-09-15

    This study monitored the influence of arsenic-contaminated irrigation water on alkaline soils and arsenic uptake in agricultural plants at field level. The arsenic concentrations in irrigation water ranges from <0.005 to 1.014 mg L{sup -1} where the arsenic concentrations in the soils were measured from 6.1 to 16.7 mg As kg{sup -1}. The arsenic content in different parts of plants are found in the order of roots > shoots > leaves > edible parts. The mean arsenic content of edible plant material (dry weight) were found in the order of onion leaves (0.55 mg As kg{sup -1}) > onion bulb (0.45 mg As kg{sup -1}) > cauliflower (0.33 mg As kg{sup -1}) > rice (0.18 mg As kg{sup -1}) > brinjal (0.09 mg As kg{sup -1}) > potato (<0.01 mg As kg{sup -1}). - The arsenic content in soil and plants is influenced by the degree of arsenic amount in irrigated water.

  9. Firearm Legislation and Fatal Police Shootings in the United States.

    Science.gov (United States)

    Kivisto, Aaron J; Ray, Bradley; Phalen, Peter L

    2017-07-01

    To examine whether stricter firearm legislation is associated with rates of fatal police shootings. We used a cross-sectional, state-level design to evaluate the effect of state-level firearm legislation on rates of fatal police shootings from January 1, 2015, through October 31, 2016. We measured state-level variation in firearm laws with legislative scorecards from the Brady Center, and for fatal police shootings we used The Counted, an online database maintained by The Guardian. State-level firearm legislation was significantly associated with lower rates of fatal police shootings (incidence rate ratio = 0.961; 95% confidence interval = 0.939, 0.984). When we controlled for sociodemographic factors, states in the top quartile of legislative strength had a 51% lower incidence rate than did states in the lowest quartile. Laws aimed at strengthening background checks, promoting safe storage, and reducing gun trafficking were associated with fewer fatal police shootings. Legislative restrictions on firearms are associated with reductions in fatal police shootings. Public Health Implications. Although further research is necessary to determine causality and potential mechanisms, firearm legislation is a potential policy solution for reducing fatal police shootings in the United States.

  10. Solvent extraction treatment of PCB contaminated soil at Sparrevohn Long Range Radar Station, Alaska

    International Nuclear Information System (INIS)

    Weimer, L. D.

    1999-01-01

    On-site soil treatment at a long range radar station in Alaska, which was contaminated with between 50 and 350 mg/kg of polychlorinated biphenyls (PCBs) is described. The stock-piled soil was treated by the Terra Kleen Response Group, using a solvent extraction process. After the treatment, PCB concentrations in the treated soil were found to have been reduced to less than the target treatment level of 15 mg/kg. Not only was the process successful, it also saved the government about $ 1 million over what hauling and off-site treatment and disposal would have cost. 1 tab

  11. Plant-soil interactions in the expansion and native range of a poleward shifting plant species

    NARCIS (Netherlands)

    Grunsven, van R.H.A.; Putten, van der W.H.; Bezemer, T.M.; Berendse, F.; Veenendaal, E.M.

    2010-01-01

    Climate warming causes range shifts of many species toward higher latitudes and altitudes. However, range shifts of host species do not necessarily proceed at the same rates as those of their enemies and symbionts. Here, we examined how a range shifting plant species performs in soil from its

  12. Plant–soil interactions in the expansion and native range of a poleward shifting plant species

    NARCIS (Netherlands)

    Van Grunsven, R.H.A.; Van der Putten, W.H.; Bezemer, T.M.; Berendse, F.; Veenendaal, E.M.

    2010-01-01

    Climate warming causes range shifts of many species toward higher latitudes and altitudes. However, range shifts of host species do not necessarily proceed at the same rates as those of their enemies and symbionts. Here, we examined how a range shifting plant species performs in soil from its

  13. Effect of immersion frequency on shoot multiplication of Bambusa vulgaris Schrader ex Wendland in RITA® TIS

    Directory of Open Access Journals (Sweden)

    Yudith García-Ramírez

    2013-04-01

    Full Text Available Bamboos are unique in bringing together a wide range of environmental services. The present work was conducted to determine the effect of immersion frequency of shoot multiplication of B. vulgaris grown in SIT. Three Immersion frequencies (every 4, 6 and 12 hours were studied. The plant height was measured and the number of shoots per explant and the number of expanded leaves per explant were quantified. Furthermore, the water content was determined in the explants. It was found that the immersion frequency influenced the in vitro multiplication of B. vulgaris. The results showed that the number of shoots (6.5 shoots / explant and the number of leaves per explant (11.0 leaves / explant were higher with immersion every six hours. The lowest values for all variables were found in explants cultured with immersion every 12 h. In this treatment water content in the explants was higher. The results indicated that with the management of the immersion frequency it can encourage the multiplication of B. vulgaris in SIT. Keywords: bamboo, in vitro propagation, water content

  14. Bioaccumulation of thallium by the wild plants grown in soils of mining area.

    Science.gov (United States)

    Sasmaz, Merve; Akgul, Bunyamin; Yıldırım, Derya; Sasmaz, Ahmet

    2016-11-01

    Gümüsköy Ag (As, Pb, and Tl) deposits are one of the largest silver deposits in the country and located about 25 km west of Kütahya, Turkey. This study investigated the accumulation and transport of thallium into 11 wild plants in soil of the mining area. Plant samples and their associated soils were collected from the field and Tl contents were measured with inductively coupled plasma mass spectroscopy (ICP-MS). The mean concentrations in the soil, roots, and shoots of the studied plants were, respectively, 170, 318, and 315 mg kg(-1) for Tl. The plants analyzed and collected from the studied area were separated into different groups based on enrichment coefficients of roots and shoots (ECR and ECS). The results showed that because of their higher ECR and ECS, the following could be good bioaccumulators: CY, IS, SL, and VR for Tl. Therefore, these plants can be useful for remediation or phytoremediation of soils polluted by Tl.

  15. The correlation of the radiocaesium concentration of new shoots harvested in 2012 and old leaves, and new shoots harvested in 2011 grown in Kanagawa prefecture

    International Nuclear Information System (INIS)

    Shiraki, Yoshiya; Takeda, Hajime; Okamoto, Tamotsu; Kita, Nobuhiro

    2013-01-01

    We conducted this study to analyze the correlation between 137 Cs concentration of new shoots harvested in the first crop of tea in 2012, and new shoots harvested in the shuto-bancha in 2011 and old leaves harvested at the same time respectively. In the first crop of tea in 2012, the 137 Cs concentration of new shoots was related to that of old leaves, and the correlation of the coefficient was 0.663(p 137 Cs concentration(new shoots/old leaves) was related to the days until harvest of the first crop of tea in 2012, and the correlation coefficient was -0.771(p 137 Cs concentration was derived from the dilution effect due to growth and development of tea plants. Regression analysis was performed to forecast the 137 Cs concentration of the new shoots in the first crop of tea. The 137 Cs concentration of new shoots in the harvested first crop of tea(Y) was related to the 137 Cs concentration of old leaves harvested the previous winter(X). The correlation of the coefficient was 0.783(p 137 Cs concentration of new shoots of the first crop of tea in 2012 decreased about 1/6 to 1/25 compared with that of new shoots of the first crop of tea in 2011. (author)

  16. Fatal school shootings and the epidemiological context of firearm mortality in the United States

    Science.gov (United States)

    Shultz, James M; Cohen, Alyssa M; Muschert, Glenn W; Flores de Apodaca, Roberto

    2013-01-01

    Background The December 14, 2012 mass shooting at Sandy Hook Elementary School in Newtown, Connecticut, USA, vaulted concerns regarding gun violence to the forefront of public attention. This high-visibility incident occurred within the epidemiological context of U.S. firearm mortality that claims more than 88 lives daily. Methods National epidemiologic data on firearm deaths over two decades were analyzed along with data registries on school shootings in order to place the tragedy at Sandy Hook in perspective. School shootings were classified as random or targeted. Results The U.S. has the highest rates of firearm deaths, suicides, and homicides among the world’s 34 “advanced economies.” Seventy percent of U.S. homicides and more than 50% of U.S. suicides are committed using a firearm. U.S. firearm homicide rates first declined, and then stabilized, during the past 23 years, 1990-2012. “Shooting massacres” in school settings, a new phenomenon within the past 50 years, are extremely rare events. Over 23 years, 1990-2012, 215 fatal school shooting incidents resulted in 363 deaths, equivalent to 0.12% of national firearm homicides during that time period. Most episodes were “targeted” shootings in which the perpetrator intentionally killed a specific individual in a school setting. Only 25 of these 215 events (11.6%) were “random” or “rampage” shootings, resulting in 135 deaths (0.04% of national firearm homicides). Among these, just three shooting rampages – Columbine High School, Virginia Tech University, and Sandy hook Elementary School – accounted for 72 (53.3%) of these 135 deaths. The frequency of random/rampage shooting incidents in schools has remained within the narrow range of 0 to 3 episodes per year. Conclusions Each year, more than 32,000 Americans die by firearms and more than 70,000 are wounded, representing a volume of preventable deaths and injuries that the U.S. government describes as a “public health crisis.” School

  17. Soil feedback and pathogen activity in Prunus serotina throughout its native range

    NARCIS (Netherlands)

    Reinhart, K.O.; Royo, A.A.; Putten, van der W.H.; Clay, K.

    2005-01-01

    1 Oomycete soil pathogens are known to have a negative effect on Prunus serotina seedling establishment and to promote tree diversity in a deciduous forest in Indiana, USA. Here, we investigate whether negative feedbacks operate widely in its native range in eastern USA. 2 In laboratory experiments,

  18. The Level of Vision Necessary for Competitive Performance in Rifle Shooting: Setting the Standards for Paralympic Shooting with Vision Impairment

    NARCIS (Netherlands)

    Allen, P.M.; Latham, K.; Mann, D.L.; Ravensbergen, H.J.C.; Myint, J.

    2016-01-01

    The aim of this study was to investigate the level of vision impairment (VI) that would reduce performance in shooting; to guide development of entry criteria to visually impaired (VI) shooting. Nineteen international-level shooters without VI took part in the study. Participants shot an air rifle,

  19. Bacterial endophytes enhance phytostabilization in soils contaminated with uranium and lead.

    Science.gov (United States)

    Ahsan, Muhammad Tayyab; Najam-Ul-Haq, Muhammad; Idrees, Muhammad; Ullah, Inayat; Afzal, Muhammad

    2017-10-03

    The combined use of plants and bacteria is a promising approach for the remediation of polluted soil. In the current study, the potential of bacterial endophytes in partnership with Leptochloa fusca (L.) Kunth was evaluated for the remediation of uranium (U)- and lead (Pb)-contaminated soil. L. fusca was vegetated in contaminated soil and inoculated with three different endophytic bacterial strains, Pantoea stewartii ASI11, Enterobacter sp. HU38, and Microbacterium arborescens HU33, individually as well as in combination. The results showed that the L. fusca can grow in the contaminated soil. Bacterial inoculation improved plant growth and phytoremediation capacity: this manifested in the form of a 22-51% increase in root length, 25-62% increase in shoot height, 10-21% increase in chlorophyll content, and 17-59% more plant biomass in U- and Pb-contaminated soils as compared to plants without bacterial inoculation. Although L. fusca plants showed potential to accumulate U and Pb in their root and shoot on their own, bacterial consortia further enhanced metal uptake capacity by 53-88% for U and 58-97% for Pb. Our results indicate that the combination of L. fusca and endophytic bacterial consortia can effectively be used for the phytostabilization of both U- and Pb-contaminated soils.

  20. Decontamination of soils polluted with heavy metals using plants as determined by nuclear technique

    International Nuclear Information System (INIS)

    Lotfy, S.M

    2010-01-01

    The objectives of this work were three folds. First, to study the mobility and fate of heavy metals in two polluted sites (Mostorud soil, irrigated with contaminated water for more than 30 years and El-Gabal EL-Asfar soil, subjected to sewage effluent irrigation for more than 50 years) utilizing a modified tessier's sequential extraction procedure to evaluate the effect of total metal concentrations on metal partitioning into different fractions. Second, to evaluate the efficiency of some plant species (sunflower, cotton, penakium, Napier grass, and Squash) to extract heavy metals out of polluted soils. Third, to enhance the phyto-extraction of heavy metals by sunflower plant using some chemical chelators (citric acids, EDTA, and Ammonium nitrate) in order to improve the remediation of pollutants as well as to protect soil quality.It was observed that the distribution of heavy metals in various chemical fractions depends on the total heavy metals content. The distribution of heavy metals forms in the studied soils was in the following decreasing order: residual > Fe-Mn oxides > carbonates > organic > exchangeable > water soluble.Either higher metal accumulation in shoots or enhanced metal accumulation in roots was mainly due to improved phyto-extraction or rhizo-filtration efficiency, respectively. Heavy metals accumulation in shoots and roots of the investigated plant species was as follow: sunflower > cotton > penakium > Napier grass > Squash with a lower order of magnitude. Sunflower showed superiority for heavy metals extraction.Application of chemical chelators (soil amendments) enhanced the phyto-extraction efficiency of heavy metals by sunflower in both Mostorud and El-Gabal El-Asfar soils. Citric acid enhanced metals accumulation in shoots and roots more than EDTA and ammonium nitrate. Citric acid with rate of 20 m mole/kg soil was the best chelators to enhance phyto- extraction of heavy metals by sunflower.

  1. Ferns: the missing link in shoot evolution and development

    Directory of Open Access Journals (Sweden)

    Andrew Robert George Plackett

    2015-11-01

    Full Text Available Shoot development in land plants is a remarkably complex process that gives rise to an extreme diversity of forms. Our current understanding of shoot developmental mechanisms comes almost entirely from studies of angiosperms (flowering plants, the most recently diverged plant lineage. Shoot development in angiosperms is based around a layered multicellular apical meristem that produces lateral organs and/or secondary meristems from populations of founder cells at its periphery. In contrast, non-seed plant shoots develop from either single apical initials or from a small population of morphologically distinct apical cells. Although developmental and molecular information is becoming available for non-flowering plants, such as the model moss Physcomitrella patens, making valid comparisons between highly divergent lineages is extremely challenging. As sister group to the seed plants, the monilophytes (ferns and relatives represent an excellent phylogenetic midpoint of comparison for unlocking the evolution of shoot developmental mechanisms, and recent technical advances have finally made transgenic analysis possible in the emerging model fern Ceratopteris richardii. This review compares and contrasts our current understanding of shoot development in different land plant lineages with the aim of highlighting the potential role that the fern C. richardii could play in shedding light on the evolution of underlying genetic regulatory mechanisms.

  2. Trichoderma reesei FS10-C enhances phytoremediation of Cd-contaminated soil by Sedum plumbizincicola and associated soil microbial activities

    Science.gov (United States)

    Teng, Ying; Luo, Yang; Ma, Wenting; Zhu, Lingjia; Ren, Wenjie; Luo, Yongming; Christie, Peter; Li, Zhengao

    2015-01-01

    This study aimed to explore the effects of Trichoderma reesei FS10-C on the phytoremediation of Cd-contaminated soil by the hyperaccumulator Sedum plumbizincicola and on soil fertility. The Cd tolerance of T. reesei FS10-C was characterized and then a pot experiment was conducted to investigate the growth and Cd uptake of S. plumbizincicola with the addition of inoculation agents in the presence and absence of T. reesei FS10-C. The results indicated that FS10-C possessed high Cd resistance (up to 300 mg L-1). All inoculation agents investigated enhanced plant shoot biomass by 6–53% of fresh weight and 16–61% of dry weight and Cd uptake by the shoots by 10–53% compared with the control. All inoculation agents also played critical roles in increasing soil microbial biomass and microbial activities (such as biomass C, dehydrogenase activity and fluorescein diacetate hydrolysis activity). Two inoculation agents accompanied by FS10-C were also superior to the inoculation agents, indicating that T. reesei FS10-C was effective in enhancing both Cd phytoremediation by S. plumbizincicola and soil fertility. Furthermore, solid fermentation powder of FS10-C showed the greatest capacity to enhance plant growth, Cd uptake, nutrient release, microbial biomass and activities, as indicated by its superior ability to promote colonization by Trichoderma. The solid fermentation powder of FS10-C might serve as a suitable inoculation agent for T. reesei FS10-C to enhance both the phytoremediation efficiency of Cd-contaminated soil and soil fertility. PMID:26113858

  3. The relationship between brightness temperature and soil moisture. Selection of frequency range for microwave remote sensing

    International Nuclear Information System (INIS)

    Rao, K.S.; Chandra, G.; Rao, P.V.N.

    1987-01-01

    The analysis of brightness temperature data acquired from field and aircraft experiments demonstrates a linear relationship between soil moisture and brightness temperature. However, the analysis of brightness temperature data acquired by the Skylab radiometer demonstrates a non-linear relationship between soil moisture and brightness temperature. In view of the above and also because of recent theoretical developments for the calculation of the dielectric constant and brightness temperature under varying soil moisture profile conditions, an attempt is made to study the theoretical relationship between brightness temperature and soil moisture as a function of frequency. Through the above analysis, the appropriate microwave frequency range for soil moisture studies is recommended

  4. Plant host range of Verticillium longisporum and microsclerotia density in Swedisch soils

    NARCIS (Netherlands)

    Johansson, A.; Goud, J.C.; Dixelius, C.

    2006-01-01

    Verticillium longisporum is a soil-borne fungal pathogen causing vascular wilt of Brassica crops. This study was conducted to enhance our knowledge on the host range of V. longisporum. Seven crop species (barley, oat, oilseed rape, pea, red clover, sugar beet and wheat) and five weed species (barren

  5. Wood-derived-biochar combined with compost or iron grit for in situ stabilization of Cd, Pb, and Zn in a contaminated soil.

    Science.gov (United States)

    Oustriere, Nadège; Marchand, Lilian; Rosette, Gabriel; Friesl-Hanl, Wolfgang; Mench, Michel

    2017-03-01

    In situ stabilization of Cd, Pb, and Zn in an Austrian agricultural soil contaminated by atmospheric depositions from a smelter plant was assessed with a pine bark chip-derived biochar, alone and in combination with either compost or iron grit. Biochar amendment was also trialed in an uncontaminated soil to detect any detrimental effect. The pot experiment consisted in ten soil treatments (% w/w): untreated contaminated soil (Unt); Unt soil amended with biochar alone (1%: B1; 2.5%: B2.5) and in combination: B1 and B2.5 + 5% compost (B1C and B2.5C), B1 and B2.5 + 1% iron grit (B1Z and B2.5Z); uncontaminated soil (Ctrl); Ctrl soil amended with 1 or 2.5% biochar (CtrlB1, CtrlB2.5). After a 3-month reaction period, the soil pore water (SPW) was sampled in potted soils and dwarf beans were grown for a 2-week period. The SPW Cd, Pb, and Zn concentrations decreased in all amended-contaminated soils. The biochar effects increased with its addition rate and its combination with either compost or iron grit. Shoot Cd and Zn removals by beans were reduced and shoot Cd, Pb, and Zn concentrations decreased to common values in all amended soils except the B1 soil. Decreases in the SPW Cd/Pb/Zn concentrations did not improve the root and shoot yields of plants as compared to the Ctrl soil.

  6. Mental illness, mass shootings, and the politics of American firearms.

    Science.gov (United States)

    Metzl, Jonathan M; MacLeish, Kenneth T

    2015-02-01

    Four assumptions frequently arise in the aftermath of mass shootings in the United States: (1) that mental illness causes gun violence, (2) that psychiatric diagnosis can predict gun crime, (3) that shootings represent the deranged acts of mentally ill loners, and (4) that gun control "won't prevent" another Newtown (Connecticut school mass shooting). Each of these statements is certainly true in particular instances. Yet, as we show, notions of mental illness that emerge in relation to mass shootings frequently reflect larger cultural stereotypes and anxieties about matters such as race/ethnicity, social class, and politics. These issues become obscured when mass shootings come to stand in for all gun crime, and when "mentally ill" ceases to be a medical designation and becomes a sign of violent threat.

  7. A network of experimental forests and ranges: Providing soil solutions for a changing world

    Science.gov (United States)

    Mary Beth. Adams

    2010-01-01

    The network of experimental forests and ranges of the USDA Forest Service represents significant opportunities to provide soil solutions to critical issues of a changing world. This network of 81 experimental forests and ranges encompasses broad geographic, biological, climatic and physical scales, and includes long-term data sets, and long-term experimental...

  8. The distribution of 137Cs in maize (Zea mays L.) and two millet species (Panicum miliaceum L. and Panicum maximum Jacq.) cultivated on the cesium-contaminated soil

    International Nuclear Information System (INIS)

    Bystrzejewska-Nowacka, G.; Nowacka, R.

    2004-01-01

    The plant of three species (Zea mays L., Panicum miliaceum L. and Panicum maximum Jacq.) were grown on the soil contaminated with 0.3 mM CsCl solution traced with 137 Cs, in greenhouse. For all the species, the fresh-to-dry weight ratio was equal in the cesium-treated plants and in the central group after 3 weeks of culture. The shoot-to root fresh weight and dry weight ratios were decreased in maize, unchanged in Panicum miliaceum and increased in Panicum maximum, comparing to the control without cesium treatment. The shoot/soil and also root/soil transfer (TF) for 137 Cs (measured by means of Na I gamma spectrometer) were always the highest in maize, then lower in Panicum miliaceum and the lowest in Panicum maximum. All the plants seem to be hyperaccumulators of cesium. The root/soil Tf was especially high in maize, i.e. 55 (kBq kg -1 biomass)/kBq Kg -1 soil). The shoot/root concentration factor (CF) for 137 Cs was the lowest in maize, higher in Panicum miliaceum and highest in Panicum maximum. The proved ability of the investigated plants for phytoextraction of the soil cesium points to the (author). The detectability and reliin soil bioremediation. From this point of view, Panicum maximum seems to be the most useful plant because it accumulates cesium mainly in the shoot, and maize would be the least useful spices since it has the highest accumulation in root. (author)

  9. Effect of silicon on reducing cadmium toxicity in durum wheat (Triticum turgidum L. cv. Claudio W.) grown in a soil with aged contamination

    International Nuclear Information System (INIS)

    Rizwan, Muhammad; Meunier, Jean-Dominique

    2012-01-01

    Highlights: ► Metal stress alleviation in wheat supplemented with amorphous Si (ASi). ► Pot experiment with a metal-contaminated soil and increased doses of ASi. ► Effects are observed both at the soil and the plant levels. ► ASi increases plant biomass and Cd content in roots and decreases Cd in shoots. ► ASi decreases soil-available Cd but is limiting for Si uptake. - Abstract: Agricultural soil contamination and subsequently crops still require alternative solutions to reduce associated environmental risks. The effects of silica application on alleviating cadmium (Cd) phytotoxicity in wheat plants were investigated in a 71-day pot experiment conducted with a historically contaminated agricultural soil. We used amorphous silica (ASi) that had been extracted from a diatomite mine for Si distribution at 0, 1, 10 and 15 ton ASi ha −1 . ASi applications increased plant biomass and plant Si concentrations, reduced the available Cd in the soil and the Cd translocation to shoots, while Cd was more efficiently sequestrated in roots. But ASi is limiting for Si uptake by plants. We conclude that significant plant-available Si in soil contributes to decreased Cd concentrations in wheat shoots and could be implemented in a general scheme aiming at controlling Cd concentrations in wheat.

  10. A compendium of results from long-range alpha detector soil surface monitoring: June 1992--May 1994

    International Nuclear Information System (INIS)

    Garner, S.E.; Bounds, J.A.; Allander, K.S.; Johnson, J.D.; MacArthur, D.W.; Caress, R.W.

    1994-11-01

    Soil surface monitors based on long-range alpha detector (LRAD) technology are being used to monitor alpha contamination at various sites in the Department of Energy complex. These monitors, the large soil-surface monitor (LSSM) and the small soil-surface monitor (SSSM), were used to help characterize sites at Fernald, Ohio, and active or inactive firing sites at Sandia National Laboratories and Los Alamos National Laboratory. Monitoring results are presented herein in chronological order

  11. Ethylenediaminedisuccinic acid (EDDS) enhances phytoextraction of lead by vetiver grass from contaminated residential soils in a panel study in the field.

    Science.gov (United States)

    Attinti, Ramesh; Barrett, Kirk R; Datta, Rupali; Sarkar, Dibyendu

    2017-06-01

    Phytoextraction is a green remediation technology for cleaning contaminated soils. Application of chelating agents increases metal solubility and enhances phytoextraction. Following a successful greenhouse experiment, a panel study under field weather elucidated the efficiency of the chelating agent ethylenediaminedisuccinic acid (EDDS) on phytoextraction of lead (Pb) by vetiver grass, a hyperaccumulator of Pb, and a nonaccumulator fescue grass from residential soils contaminated with Pb-based paint from Baltimore, MD and San Antonio, TX. Three soils from each city with Pb content between 1000 and 2400 mg kg -1 were chosen for the panel study. Sequential extraction revealed that Fe-Mn oxide (60-63%) and carbonate (25-33%) fractions of Pb dominated in Baltimore soils, whereas in San Antonio soils, Pb was primarily bound to the organic fraction (64-70%) because organic content was greater and, secondarily, to the Fe-Mn oxide (15-20%) fraction. Vetiver and fescue grasses were transplanted and grown on wood panels in the field with EDDS applied after 3 months and 13 months. Soil and leachate results indicated that EDDS applications increased Pb solubility in soils. Plant tissues results indicated enhanced the uptake of Pb by vetiver and showed that EDDS application promoted translocation of Pb from root to shoot. Average Pb concentration increased by 53% and 203% in shoots and by 73% and 84% in roots of vetiver after the first and second applications of EDDS, respectively. Concentrations in roots and shoots increased in all tested soils, regardless of soil pH or clay content. After the second application, average Pb concentrations in vetiver were higher than those in fescue by 3.6x in shoots and 8.3x in roots. Visual phytotoxic symptoms from increased bioavailable Pb from EDSS applications were observed in fescue but not in vetiver. This study demonstrated the potential of a chemically-catalyzed phytoremediation system as a cleanup method for lead-contaminated soils

  12. Effect of fertilizer amendments on phytoremediation of Cd-contaminated soil by a newly discovered hyperaccumulator Solanum nigrum L

    International Nuclear Information System (INIS)

    Wei Shuhe; Li Yunmeng; Zhou Qixing; Srivastava, Mrittunjai; Chiu Siuwai; Zhan Jie; Wu Zhijie; Sun Tieheng

    2010-01-01

    Phytoremediation is a cost-effective, simple and sustainable beneficiary technique to purify the polluted environment. Solanum nigrum L., a newly found cadmium (Cd) hyperaccumulator, has shown the potential to remediate Cd-contaminated soils. Present study investigated the effects of fertilizer amendments on the Cd uptake by S. nigrum. Chicken manure and urea are usual agricultural fertilizers and more environmental friendly. The results showed that Cd concentrations in shoots of S. nigrum were significantly decreased (p -1 ) in shoot biomass of S. nigrum were significantly increased (p < 0.05) due to increased shoot biomass. In addition, available Cd concentration in soil significantly decreased due to addition of chicken manure. Thus, urea might be a better fertilizer for strengthening phytoextraction rate of S. nigrum to Cd, and chicken manure may be a better fertilizer for phytostabilization.

  13. In situ stabilization remediation of cadmium contaminated soils of wastewater irrigation region using sepiolite.

    Science.gov (United States)

    Sun, Yuebing; Sun, Guohong; Xu, Yingming; Wang, Lin; Lin, Dasong; Liang, Xuefeng; Shi, Xin

    2012-01-01

    The effects of immobilization remediation of Cd-contaminated soils using sepiolite on soil pH, enzyme activities and microbial communities, TCLP-Cd (toxicity characteristic leaching procedure-Cd) concentration, and spinach (Spinacia oleracea) growth and Cd uptake and accumulation were investigated. Results showed that the addition of sepiolite could increase soil pH, while the TCLP-Cd concentration in soil was decreased with increasing sepiolite. The changes of soil enzyme activities and bacteria number indicated that a certain metabolic recovery occurred after the sepiolite treatments, and spinach shoot biomass increased by 58.5%-65.5% in comparison with the control group when the concentration of sepiolite was < or = 10 g/kg. However, the Cd concentrations in the shoots and roots of spinach decreased with an increase in the rate of sepiolite, experiencing 38.4%-59.1% and 12.6%-43.6% reduction, respectively, in contrast to the control. The results indicated that sepiolite has the potential for success on a field scale in reducing Cd entry into the food chain.

  14. Impacts of coal fly ash on plant growth and accumulation of essential nutrients and trace elements by alfalfa (Medicago sativa) grown in a loessial soil.

    Science.gov (United States)

    He, Honghua; Dong, Zhigang; Peng, Qi; Wang, Xia; Fan, Chenbin; Zhang, Xingchang

    2017-07-15

    Coal fly ash (CFA) is a problematic solid waste all over the world. One distinct beneficial reuse of CFA is its utilization in land application as a soil amendment. A pot experiment was carried out to assess the feasibility of using CFA to improve plant growth and increase the supply of plant-essential elements and selenium (Se) of a loessial soil for agricultural purpose. Plants of alfalfa (Medicago sativa) were grown in a loessial soil amended with different rates (5%, 10%, 20% and 40%) of CFA for two years and subjected to four successive cuttings. Dry mass of shoots and roots, concentrations of plant-essential elements and Se in plants were measured. Shoot dry mass and root dry mass were always significantly increased by 5%, 10% and 20% CFA treatments, and by 40% CFA treatment in all harvests except the first one. The CFA had a higher supply of exchangeable phosphorus (P), magnesium (Mg), copper (Cu), zinc (Zn), molybdenum (Mo), and Se than the loessial soil. Shoot P, calcium (Ca), Mg, Mo, boron (B), and Se concentrations were generally markedly increased, but shoot potassium (K), Cu, and Zn concentrations were generally reduced. The CFA can be a promising source of some essential elements and Se for plants grown in the loessial soil, and an application rate of not higher than 5% should be safe for agricultural purpose without causing plant toxicity symptoms in the studied loessial soil and similar soils. Field trials will be carried out to confirm the results of the pot experiment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Effect of new organic supplement (Panchgavya) on seed germination and soil quality.

    Science.gov (United States)

    Jain, Paras; Sharma, Ravi Chandra; Bhattacharyya, Pradip; Banik, Pabitra

    2014-04-01

    We studied the suitability of Panchgavya (five products of cow), new organic amendment, application on seed germination, plant growth, and soil health. After characterization, Panchgavya was mixed with water to form different concentration and was tested for seed germination, germination index, and root and shoot growth of different seedlings. Four percent solution of Panchgavya was applied to different plants to test its efficacy. Panchgavya and other two organic amendments were incorporated in soil to test the change of soil chemical and microbiological parameters. Panchgavya contained higher nutrients as compared to farm yard manure (FYM) and vermicompost. Its application on different seeds has positively influenced germination percentage, germination index, root and shoot length, and fresh and dry weight of the seedling. Water-soluble macronutrients including pH and metal were positively and negatively correlated with the growth parameters, respectively. Four percent solution of Panchgavya application on some plants showed superiority in terms of plant height and chlorophyll content. Panchgavya-applied soil had higher values of macro and micronutrients (zinc, copper, and manganese), microbial activity as compared to FYM, and vermicompost applied soils. Application of Panchgavya can be gainfully used as an alternative organic supplement in agriculture.

  16. Phytoextraction of toxic trace elements by Sorghum bicolor inoculated with Streptomyces pactum (Act12) in contaminated soils.

    Science.gov (United States)

    Ali, Amjad; Guo, Di; Mahar, Amanullah; Wang, Ping; Ma, Fang; Shen, Feng; Li, Ronghua; Zhang, Zengqiang

    2017-05-01

    The increasing industrial, mining and agricultural activities have intensified the release of potential toxic trace elements (PTEs), which are of great concern to human health and environment. The alarming increase in PTEs concentration, stress the need for biotechnological remediation approaches. In order to assist phytoextraction of PTEs, different combinations of Streptomyces pactum (Act12) with biochar were applied to mining and industrial polluted soils of Shaanxi and Hunan Provinces of China, respectively. Act12 affected soil physico-chemical properties in both soils. Bioavailable Zn and Pb increased due to microbial activities, while Cd decreased by adsorption on biochar surface. Phytoextraction of Zn and Pb occurred in TG and CZ soil, while Cd uptake decreased in iron rich CZ soil by conflicting effect of siderophores. Cd in sorghum shoot was below detection level, but uptake increased in the roots due to minimum available fraction in TG soil. Biochar reduced the shoot and root uptake of Cd. Sorghum shoot, root dry weight and chlorophyll significantly increased after Act12 and biochar application. β-glucosidase, alkaline phosphatase and urease activities were significantly enhanced by Act12. Antioxidant enzymatic activities (POD, PAL and PPO) and lipid peroxidation (MDA) were decreased after the application of Act12 and biochar by reduced PTEs stress. Act12 and biochar can be used for different crops to enumerate the transfer rate of PTEs into the food chain. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Enhanced phytoextraction of uranium and selected heavy metals by Indian mustard and ryegrass using biodegradable soil amendments

    Energy Technology Data Exchange (ETDEWEB)

    Duquene, L. [SCK-CEN, Biosphere Impact Studies, Boeretang 200, B-2400 Mol (Belgium); Vandenhove, H. [SCK-CEN, Biosphere Impact Studies, Boeretang 200, B-2400 Mol (Belgium)], E-mail: hvandenh@sckcen.be; Tack, F.; Meers, E. [Ghent University, Laboratory for Analytical Chemistry and Applied Ecochemistry, Coupure Links 653, B-9000 Gent (Belgium); Baeten, J. [Katholieke Hogeschool Kempen, Department of Health-Care and Chemistry, Kleinhoefstraat 4, B-2440 Geel (Belgium); Wannijn, J. [SCK-CEN, Biosphere Impact Studies, Boeretang 200, B-2400 Mol (Belgium)

    2009-02-15

    The applicability of biodegradable amendments in phytoremediation to increase the uptake of uranium (U), cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb) and zinc (Zn) by Indian mustard (Brassica juncea) and ryegrass (Lolium perenne) was tested in a greenhouse experiment. Plants were cultivated during one month on two soils with naturally or industrially increased contaminant levels of U. Treatments with citric acid, NH{sub 4}-citrate/citric acid, oxalic acid, S,S-ethylenediamine disuccinic acid (EDDS) or nitrilotriacetic acid (NTA) at a rate of 5 mmol kg{sup -1} dry soil caused increases in soil solution concentrations that were up to 18 times higher for U and up to 1570 times higher for other heavy metals, compared to the controls. Shoot concentrations increased to a much smaller extent. With EDDS, 19-, 34-, and 37-fold increases were achieved in shoots of Indian mustard for U, Pb and Cu, respectively. The increases in plant uptake of Cd, Cr and Zn were limited to a factor of four at most. Ryegrass generally extracted less U and metals than Indian mustard. Despite a marked increase of U and metal concentrations in shoots after addition of amendments, the estimated time required to obtain an acceptable reduction in soil contaminant concentrations was impractically long. Only for Cu and Zn in one of the studied soils, could the Flemish standards for clean soil theoretically be attained in less than 100 years.

  18. Enhanced phytoextraction of uranium and selected heavy metals by Indian mustard and ryegrass using biodegradable soil amendments

    International Nuclear Information System (INIS)

    Duquene, L.; Vandenhove, H.; Tack, F.; Meers, E.; Baeten, J.; Wannijn, J.

    2009-01-01

    The applicability of biodegradable amendments in phytoremediation to increase the uptake of uranium (U), cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb) and zinc (Zn) by Indian mustard (Brassica juncea) and ryegrass (Lolium perenne) was tested in a greenhouse experiment. Plants were cultivated during one month on two soils with naturally or industrially increased contaminant levels of U. Treatments with citric acid, NH 4 -citrate/citric acid, oxalic acid, S,S-ethylenediamine disuccinic acid (EDDS) or nitrilotriacetic acid (NTA) at a rate of 5 mmol kg -1 dry soil caused increases in soil solution concentrations that were up to 18 times higher for U and up to 1570 times higher for other heavy metals, compared to the controls. Shoot concentrations increased to a much smaller extent. With EDDS, 19-, 34-, and 37-fold increases were achieved in shoots of Indian mustard for U, Pb and Cu, respectively. The increases in plant uptake of Cd, Cr and Zn were limited to a factor of four at most. Ryegrass generally extracted less U and metals than Indian mustard. Despite a marked increase of U and metal concentrations in shoots after addition of amendments, the estimated time required to obtain an acceptable reduction in soil contaminant concentrations was impractically long. Only for Cu and Zn in one of the studied soils, could the Flemish standards for clean soil theoretically be attained in less than 100 years

  19. Enhanced phytoextraction of uranium and selected heavy metals by Indian mustard and ryegrass using biodegradable soil amendments.

    Science.gov (United States)

    Duquène, L; Vandenhove, H; Tack, F; Meers, E; Baeten, J; Wannijn, J

    2009-02-15

    The applicability of biodegradable amendments in phytoremediation to increase the uptake of uranium (U), cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb) and zinc (Zn) by Indian mustard (Brassica juncea) and ryegrass (Lolium perenne) was tested in a greenhouse experiment. Plants were cultivated during one month on two soils with naturally or industrially increased contaminant levels of U. Treatments with citric acid, NH4-citrate/citric acid, oxalic acid, S,S-ethylenediamine disuccinic acid (EDDS) or nitrilotriacetic acid (NTA) at a rate of 5 mmol kg(-1) dry soil caused increases in soil solution concentrations that were up to 18 times higher for U and up to 1570 times higher for other heavy metals, compared to the controls. Shoot concentrations increased to a much smaller extent. With EDDS, 19-, 34-, and 37-fold increases were achieved in shoots of Indian mustard for U, Pb and Cu, respectively. The increases in plant uptake of Cd, Cr and Zn were limited to a factor of four at most. Ryegrass generally extracted less U and metals than Indian mustard. Despite a marked increase of U and metal concentrations in shoots after addition of amendments, the estimated time required to obtain an acceptable reduction in soil contaminant concentrations was impractically long. Only for Cu and Zn in one of the studied soils, could the Flemish standards for clean soil theoretically be attained in less than 100 years.

  20. Influence of Plant Growth Regulators and Humic Substance on the Phytoremediation of Nickel in a Ni-Polluted Soil

    Directory of Open Access Journals (Sweden)

    Mahshid Shafigh

    2017-06-01

    Full Text Available Introduction: Plants can uptake, bioaccumulate and immobilize different metals in their tissues. Phytoremediation technique has been used to remove hazardous substances including heavy metals from the environment. Assisted phytoremediation is usually the process of applying a chemical additive to heavy metal contaminated soils to enhance the metal uptake by plants. The main objective of present study was to investigate the effectiveness of plant growth regulators (PGRs and a humic substance (HS on Ni phytoremediation by maize in a Ni-pollutrd calcareous soil. Materials and Methods: The experiment designed as a 5×3 factorial trial arranged in a completely randomized design with three replicates. Three kilograms of soil was placed in plastic pots and pots were watered with distilled water to field capacity and maintained at this moisture level throughout the experiment by watering the pots to a constant weight. The soils were polluted with 250 mg Ni Kg-1 as Ni-nitrate Ni (NO32. Six maize (Zea mays L. seeds were planted 2 cm deep in soil and thinned to three uniform stands 1 week after emergence. Treatments consisted of three levels of soil application of commercially humic substance, HS, (0, 3, and 6 mg kg as Humax 95-WSG containing about 80% humic acid, and about 15% fulvic acid and five levels of PGRs (0 or 10 µM GA3, IAA, BAP and SA. The HS was applied as split doses in three times at 15 day intervals along with irrigation water. The seedlings were exposed to aqueous solutions of HS 16 days after sowing for the first time. Prepared solutions of PGRs were sprayed three times at 15 day intervals from emergence. Seven weeks after planting, shoots were harvested and roots were separated from soil carefully, both parts were rinsed with distilled water and dried at 65°C for 72 h, weighed, ground, and dry meshed at 550°C. Root and shoot dry matter and Ni concentration and uptake and phytoremediation criteria were considered as plant responses

  1. In vitro mass propagation of Salvia canariensis by axillary shoots

    Directory of Open Access Journals (Sweden)

    Sebastiana Mederos Molina

    2014-01-01

    Full Text Available During the establishment of shoots of Salvia canariensis L., five environmental factor treatments were applied. For each axillary node two shoots grew well when explants were incubated at continued ligth for 15 days followed by 16 hrs photoperiod by 30 days. Shoots multiplication was improved on a modified Murashige and Skoog (MS (1962 medium - MS + 825 mg/l NH4NO3 - supplemented with 10-7 M BA and 10-7 M NAA. The shoots produced well developed root systems within three weeks after transfer to the same culture medium supplemented with 5x 10-7 M NAA.

  2. Evaluation of Vermicompost and Nitrogen Biofertilizer Effects on Flowering Shoot Yield, Essential Oil and Mineral Uptake (N, P and K in Summer Savory (Satureja hortensis L.

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Haj Seyed Hadi

    2018-02-01

    Full Text Available Introduction Summer Savory (Satureia hortensis L. is the representative plants of Lamiaceae family, which has high significant nutritional and taste values. Its pharmacopoeial raw material is herb (Satureiae herba, which contains many different biologically active compounds beside essential oil and minerals like calcium, potassium, magnesium, iron, and zinc. Sustainable agricultural systems has became an important issue throughout the world. It is obvious that intensive cultivation has led to a rapid decline in organic matter and nutrient levels as well as affecting the physical soil properties . The biofertilizers practice (such as vermicompost and biological nitrogen fixing bacteria has been recognized for a long time as an effective means of improving the structure and fertility of the soil, increasing the microbial diversity, activity and population, improving the water storage capacity of soils and crop yield. Materials and Methods This investigation was conducted at agricultural research fields of RAN Company at Firouzkuh, Iran in 2015. Factorial experiment based on randomized complete blocks design with two factors and three replications were chosen as an experimental design. The factors were biological nitrogen fertilizer at three levels of Control, Nitroxine and Supernitroplus, and vermicompost at four levels 0, 5, 10 and 15 ton per hectare. Measured traits consisted of fresh and dry plant weight, flowering shoot yield, essential oil content, nitrogen, phosphorus and potassium percentage in aboveground shoots. All data were subjected to statistical analysis (one-way ANOVA using SAS software. Duncan’s multiple range test (DMRT at 5% probability level were performed to calculate means of comparison. Data were transformed when necessary before analysis to satisfy the assumptions of normality. Results and Discussion Results showed that the highest fresh and dry plant weight (41.10 and 12.93g/plant, respectively and essential oil content

  3. Cry1Ab protein from Bt transgenic rice does not residue in rhizosphere soil

    International Nuclear Information System (INIS)

    Wang Haiyan; Ye Qingfu; Wang Wei; Wu Licheng; Wu Weixiang

    2006-01-01

    Expression of Cry1Ab protein in Bt transgenic rice (KMD) and its residue in the rhizosphere soil during the whole growth in field, as well as degradation of the protein from KMD straw in five soils under laboratory incubation were studied. The residue of Cry1Ab protein in KMD rhizosphere soil was undetectable (below the limit of 0.5 ng/g air-dried soil). The Cry1Ab protein contents in the shoot and root of KMD were 3.23-8.22 and 0.68-0.89 μg/g (fresh weight), respectively. The half-lives of the Cry1Ab protein in the soils amended with KMD straw (4%, w/w) ranged from 11.5 to 34.3 d. The residence time of the protein varied significantly in a Fluvio-marine yellow loamy soil amended with KMD straw at the rate of 3, 4 and 7%, with half-lives of 9.9, 13.8 and 18 d, respectively. In addition, an extraction method for Cry1Ab protein in soil was developed, with extraction efficiencies of 46.4-82.3%. - Cry1Ab protein was not detected in the rhizosphere soil of field-grown Bt transgenic rice

  4. Expression of the Arabidopsis vacuolar H+-pyrophosphatase gene (AVP1) improves the shoot biomass of transgenic barley and increases grain yield in a saline field

    KAUST Repository

    Schilling, Rhiannon K.

    2013-11-22

    Cereal varieties with improved salinity tolerance are needed to achieve profitable grain yields in saline soils. The expression of AVP1, an Arabidopsis gene encoding a vacuolar proton pumping pyrophosphatase (H+-PPase), has been shown to improve the salinity tolerance of transgenic plants in greenhouse conditions. However, the potential for this gene to improve the grain yield of cereal crops in a saline field has yet to be evaluated. Recent advances in high-throughput nondestructive phenotyping technologies also offer an opportunity to quantitatively evaluate the growth of transgenic plants under abiotic stress through time. In this study, the growth of transgenic barley expressing AVP1 was evaluated under saline conditions in a pot experiment using nondestructive plant imaging and in a saline field trial. Greenhouse-grown transgenic barley expressing AVP1 produced a larger shoot biomass compared to segregants, as determined by an increase in projected shoot area, when grown in soil with 150 mm NaCl. This increase in shoot biomass of transgenic AVP1 barley occurred from an early growth stage and also in nonsaline conditions. In a saline field, the transgenic barley expressing AVP1 also showed an increase in shoot biomass and, importantly, produced a greater grain yield per plant compared to wild-type plants. Interestingly, the expression of AVP1 did not alter barley leaf sodium concentrations in either greenhouse- or field-grown plants. This study validates our greenhouse-based experiments and indicates that transgenic barley expressing AVP1 is a promising option for increasing cereal crop productivity in saline fields. © 2013 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

  5. Expression of the Arabidopsis vacuolar H+-pyrophosphatase gene (AVP1) improves the shoot biomass of transgenic barley and increases grain yield in a saline field

    KAUST Repository

    Schilling, Rhiannon K.; Marschner, Petra; Shavrukov, Yuri N.; Berger, Bettina; Tester, Mark A.; Roy, Stuart John; Plett, Darren Craig

    2013-01-01

    Cereal varieties with improved salinity tolerance are needed to achieve profitable grain yields in saline soils. The expression of AVP1, an Arabidopsis gene encoding a vacuolar proton pumping pyrophosphatase (H+-PPase), has been shown to improve the salinity tolerance of transgenic plants in greenhouse conditions. However, the potential for this gene to improve the grain yield of cereal crops in a saline field has yet to be evaluated. Recent advances in high-throughput nondestructive phenotyping technologies also offer an opportunity to quantitatively evaluate the growth of transgenic plants under abiotic stress through time. In this study, the growth of transgenic barley expressing AVP1 was evaluated under saline conditions in a pot experiment using nondestructive plant imaging and in a saline field trial. Greenhouse-grown transgenic barley expressing AVP1 produced a larger shoot biomass compared to segregants, as determined by an increase in projected shoot area, when grown in soil with 150 mm NaCl. This increase in shoot biomass of transgenic AVP1 barley occurred from an early growth stage and also in nonsaline conditions. In a saline field, the transgenic barley expressing AVP1 also showed an increase in shoot biomass and, importantly, produced a greater grain yield per plant compared to wild-type plants. Interestingly, the expression of AVP1 did not alter barley leaf sodium concentrations in either greenhouse- or field-grown plants. This study validates our greenhouse-based experiments and indicates that transgenic barley expressing AVP1 is a promising option for increasing cereal crop productivity in saline fields. © 2013 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

  6. Morphological Evaluation of Shoots Regenerated from Hygromycin-Resistant Rice Callus (cv IACuba-28

    Directory of Open Access Journals (Sweden)

    Maylin Pérez Bernal

    2007-01-01

    Full Text Available An evaluation system based on the morphological characteristics of regenerated hygromycin-resistant rice callus shoots was established for correlating such characteristics with shoot viability on hygromycin. Embryogenic rice calli were transformed by Agrobacterium tumefaciens (EHA105/ pCAMBIA1300, containing the hygromycin-phosphotransferase gene as selection marker. After two weeks on selection medium, hygromycin-resistant calli were transferred to regeneration medium. Regenerated shoots were extracted every 5 days (over a 30-day period and classified into three classes according to their morphological structure: class I: vigorous shoot having typical bipolar structure; class II: shoot having small root compared to apical length, or shoot without roots; class III: shoots having an abnormal appearance, such as malformed leaves or albinism. Individualised shoots were transferred to MS medium containing hygromycin for evaluating their resistance to antibiotics. A relationship was observed between regenerated shoots’ morphological characteristics and the percentage of shoots’ viability on hygromycin. Class I prevailed at early shoot extraction and was the most resistant to hygromycin. Drastic class I reduction was found with later shoot extraction, whilst classes II and III became increased. Likewise, shoot viability became radically reduced on MS medium containing hygromycin. This result might be applied for improving efficiency regarding obtaining transgenic rice plants, taking into account the best time for obtaining high percentages of hygromycin-resistant shoots having the best morphological characteristics.

  7. Role of extrinsic arbuscular mycorrhizal fungi in heavy metal-contaminated wetlands with various soil moisture levels.

    Science.gov (United States)

    Zheng, S; Wang, C; Shen, Z; Quan, Y; Liu, X

    2015-01-01

    This study presents an efficient heavy metal (HM) control method in HM-contaminated wetlands with varied soil moisture levels through the introduction of extrinsic arbuscular mycorrhizal fungi (AMF) into natural wetland soil containing indigenous AMF species. A pot culture experiment was designed to determine the effect of two soil water contents (5-8% and 25-30%), five extrinsic AMF inoculants (Glomus mosseae, G. clarum, G. claroideum, G. etunicatum, and G. intraradices), and HM contamination on root colonization, plant growth, and element uptake of common reed (Phragmites australis (Cav.) Trin. ex Steudel) plantlets in wetland soils. This study showed the prevalence of mycorrhizae in the roots of all P. australis plantlets, regardless of extrinsic AMF inoculations, varied soil moisture or HM levels. It seems that different extrinsic AMF inoculations effectively lowered HM concentrations in the aboveground tissues of P. australis at two soil moisture levels. However, metal species, metal concentrations, and soil moisture should also be very important factors influencing the elemental uptake performance of plants in wetland ecosystems. Besides, the soil moisture level significantly influenced plant growth (including height, and shoot and root dry weight (DW)), and extrinsic AMF inoculations differently affected shoot DW.

  8. Soil moisture datasets at five sites in the central Sierra Nevada and northern Coast Ranges, California

    Science.gov (United States)

    Stern, Michelle A.; Anderson, Frank A.; Flint, Lorraine E.; Flint, Alan L.

    2018-05-03

    In situ soil moisture datasets are important inputs used to calibrate and validate watershed, regional, or statewide modeled and satellite-based soil moisture estimates. The soil moisture dataset presented in this report includes hourly time series of the following: soil temperature, volumetric water content, water potential, and total soil water content. Data were collected by the U.S. Geological Survey at five locations in California: three sites in the central Sierra Nevada and two sites in the northern Coast Ranges. This report provides a description of each of the study areas, procedures and equipment used, processing steps, and time series data from each site in the form of comma-separated values (.csv) tables.

  9. Shoot Differentiation in Callus Cultures of Datura Innoxia

    DEFF Research Database (Denmark)

    Engvild, Kjeld Christensen

    1973-01-01

    promoted shoot differentiation. Gibberellic acid inhibited shoot formation weakly, but inhibited proper leaf blade formation. Root differentiation was rare. The callus cultures of Datura innoxia grew rapidly (100-fold in 4 weeks) on a slightly modified Murashige and Skoog medium (0.5 mg/l thiamin · HCl, p...

  10. Handgun Acquisitions in California After Two Mass Shootings.

    Science.gov (United States)

    Studdert, David M; Zhang, Yifan; Rodden, Jonathan A; Hyndman, Rob J; Wintemute, Garen J

    2017-05-16

    Mass shootings are common in the United States. They are the most visible form of firearm violence. Their effect on personal decisions to purchase firearms is not well-understood. To determine changes in handgun acquisition patterns after the mass shootings in Newtown, Connecticut, in 2012 and San Bernardino, California, in 2015. Time-series analysis using seasonal autoregressive integrated moving-average (SARIMA) models. California. Adults who acquired handguns between 2007 and 2016. Excess handgun acquisitions (defined as the difference between actual and expected acquisitions) in the 6-week and 12-week periods after each shooting, overall and within subgroups of acquirers. In the 6 weeks after the Newtown and San Bernardino shootings, there were 25 705 (95% prediction interval, 17 411 to 32 788) and 27 413 (prediction interval, 15 188 to 37 734) excess acquisitions, respectively, representing increases of 53% (95% CI, 30% to 80%) and 41% (CI, 19% to 68%) over expected volume. Large increases in acquisitions occurred among white and Hispanic persons, but not among black persons, and among persons with no record of having previously acquired a handgun. After the San Bernardino shootings, acquisition rates increased by 85% among residents of that city and adjacent neighborhoods, compared with 35% elsewhere in California. The data relate to handguns in 1 state. The statistical analysis cannot establish causality. Large increases in handgun acquisitions occurred after these 2 mass shootings. The spikes were short-lived and accounted for less than 10% of annual handgun acquisitions statewide. Further research should examine whether repeated shocks of this kind lead to substantial increases in the prevalence of firearm ownership. None.

  11. Transfer of lead (Pb) in the soil-plant-mealybug-ladybird beetle food chain, a comparison between two host plants.

    Science.gov (United States)

    Zhang, Can; Wang, Xingmin; Ashraf, Umair; Qiu, Baoli; Ali, Shaukat

    2017-09-01

    Contamination of soil with heavy metals has become an issue of concern on global scale. This study investigates the translocation of lead (Pb) along the soil - plant (eggplant and tomato) - mealybug (Dysmicoccus neobrevipes) - ladybird beetle (Cryptolaemus montrouzieri) food chain. Soil amendments used for this study were adjusted to 0, 25, 50 and 100mg/kg of Pb (w/w). The results revealed significantly higher transfer of Pb in tomato when compared to eggplant. Bio-magnification of Pb (2-4 times) was observed for soil - root transfer whereas Pb was bio-minimized in later part of food chain (shoot - mealybug - ladybird transfer). A dose dependent increase in transfer of Pb across the multi-trophic food chain was observed for both host plants. A decrease in coefficients of Pb transfer (from root - shoot and shoot - mealybug) was observed with increase in Pb concentrations. Our results also showed removal of Pb from the bodies of ladybird beetle during metamorphosis. Further studies are required to explain the mechanisms or physiological pathways involved in the bio-minimization of Pb across the food chain. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Phytoremediation of soil co-contaminated with heavy metals and TNT using four plant species.

    Science.gov (United States)

    Lee, Insook; Baek, Kyunghwa; Kim, Hyunhee; Kim, Sunghyun; Kim, Jaisoo; Kwon, Youngseok; Chang, Yoontoung; Bae, Bumhan

    2007-11-01

    We investigated the germination, growth rates and uptake of contaminants of four plant species, barnyard grass (Echinochloa crusgalli), sunflower (Helianthus annuus), Indian mallow (Abutilon avicennae) and Indian jointvetch (Aeschynomene indica), grown in soil contaminated with cadmium (Cd), lead (Pb) and 2,4,6-trinitrotoluene (TNT). These contaminants are typically found at shooting ranges. Experiments were carried out over 180 days using both single plant cultures and cultures containing an equal mix of the 4 plant species. Germination rates differed among the species in single culture (92% for H. annuus, 84% for E. crusgalli, 48% for A. avicennae and 38% Ae. indica). In the 4-plant mix culture, phytoremediation for the removal of heavy metals and TNT from contaminated soils should use a single plant species rather than a mixture of several plants.

  13. Effect of coppicing height on the regeneration and productivity of certain firewood shrubs in alkaline soils of north Indian plains

    Energy Technology Data Exchange (ETDEWEB)

    Misra, P.N.; Tewari, S.K.; Singh, Dheer; Katiyar, R.S. [National Botanical Research Inst., Lucknow (India)

    1995-12-31

    Four shrubs, viz. Hibiscus tiliaceus, Leucaena leucocephala, Vitex negundo and Sesbania sesban, were evaluated for their performance as firewood crops in coppiced stands of varying cutting heights (15, 30 and 45 cm) in repeated annual harvests (4) on alkaline soils of the North Indian plains. The dry wood yield of Leucaena and Sesbania ranged between 22.9-42.6 and 9.9-18.0 tonnes ha{sup -1} year{sup -1}, respectively. Leucaena showed progressive increases in yield from coppiced stumps up to the 4th harvest while Sesbania showed a reduction after the third harvest mainly due to the high degeneration (60%) of coppiced stumps. Degeneration was low (< 10%) in Leucaena and Vitex. The coppicing heights generally did not show any significant effect on the growth and productivity. The number of coppice shoots per stump increased with stump height and production of coppice shoots was maximum in Vitex and minimum in Leucaena. The average diameter of coppice shoots tended to decrease with increasing coppicing height of the stumps. (author)

  14. Responses of seminal wheat seedling roots to soil water deficits.

    Science.gov (United States)

    Trejo, Carlos; Else, Mark A; Atkinson, Christopher J

    2018-04-01

    The aims of this paper are to develop our understanding of the ways by which soil water deficits influence early wheat root growth responses, particularly how seminal roots respond to soil drying and the extent to which information on differences in soil water content are conveyed to the shoot and their impact on shoot behaviour. To achieve this, wheat seedlings have been grown, individually for around 25 days after germination in segmented soil columns within vertical plastic compartments. Roots were exposed to different soil volumetric moisture contents (SVMC) within the two compartments. Experiments where the soil in the lower compartment was allowed to dry to different extents, while the upper was maintained close to field capacity, showed that wheat seedlings allocated proportionally more root dry matter to the lower drier soil compartment. The total production of root, irrespective of the upper or lower SVMC, was similar and there were no detected effects on leaf growth rate or gas exchange. The response of seminal roots to proportionally increase their allocation of dry matter, to the drier soil was unexpected with such plasticity of roots system development traditionally linked to heterogeneous nutrient distribution than accessing soil water. In experiments where the upper soil compartment was allowed to dry, root growth slowed and leaf growth and gas exchange declined. Subsequent experiments used root growth rates to determine when seminal root tips first came into contact with drying soil, with the intentions of determining how the observed root growth rates were maintained as an explanation for the observed changes in root allocation. Measurements of seminal root ABA and ethylene from roots within the drying soil are interpreted with respect to what is known about the physiological control of root growth in drying soil. Copyright © 2018 Elsevier GmbH. All rights reserved.

  15. The Effect of High School Shootings on Schools and Student Performance

    OpenAIRE

    Louis-Philippe Beland; Dongwoo Kim

    2015-01-01

    We analyze how fatal shootings in high schools affect schools and students using data from shooting databases, school report cards, and the Common Core of Data. We examine schools’ test scores, enrollment, and number of teachers, as well as graduation, attendance, and suspension rates at schools that experienced a shooting, employing a difference-in-differences strategy that uses other high schools in the same district as the comparison group. Our findings suggest that homicidal shootings s...

  16. Methodology of shooting training using modern IT techniques

    Science.gov (United States)

    Gudzbeler, Grzegorz; Struniawski, Jarosław

    2017-08-01

    Mastering, improvement, shaping and preservation of skills of safe, efficient and effective use of the firearm requires the use of relevant methodology of conducting the shooting training. However reality of police trainings does not usually allow for intensive training shooting with the use of ammunition. An alternative solution is the use of modern training technologies. Example of this is the "Virtual system of improvement tactics of intervention services responsible for security and shooting training." Introduction of stimulator to police trainings will enable complete stuff preparation to achieve its tasks, creating potential of knowledge and experience in many areas, far exceeding the capabilities of conventional training.

  17. [Genetic regulation of plant shoot stem cells].

    Science.gov (United States)

    Al'bert, E V; Ezhova, T A

    2013-02-01

    This article describes the main features of plant stem cells and summarizes the results of studies of the genetic control of stem cell maintenance in the apical meristem of the shoot. It is demonstrated that the WUS-CLV gene system plays a key role in the maintenance of shoot apical stem cells and the formation of adventitious buds and somatic embryos. Unconventional concepts of plant stem cells are considered.

  18. Concentration/time-dependent dissipation, partitioning and plant accumulation of hazardous current-used pesticides and 2-hydroxyatrazine in sand and soil.

    Science.gov (United States)

    Neuwirthová, Natália; Bílková, Zuzana; Vašíčková, Jana; Hofman, Jakub; Bielská, Lucie

    2018-07-01

    The dissipation, partitioning dynamics and biouptake was measured for selected hazardous current-used pesticides (conazole fungicides: epoxiconazole, flusilazole, tebuconazole; prochloraz, chlorpyrifos, pendimethalin) and for a transformation product (2-hydroxyatrazine) in agricultural soil and quartz sand as representatives of a real and a worst-case scenario. Dissipation, uptake to Lactuca sativa and the freely dissolved concentration along with the organic carbon-normalized sorption coefficients (K oc ) were determined on days 12, 40, and 90 following the application of compounds at three fortification levels (0.1-1.0-10 mg/kg). Conazole fungicides showed similar dissipation patterns and were more persistent in soil than prochloraz, chlorpyrifos and pendimethalin. 2-Hydroxyatrazine showed a concentration-depended decrease in persistency in soil. Lettuce roots were shown to accumulate higher amounts than shoots where the extent of root uptake was driven by compound partitioning. This was evidenced by the ability of freely dissolved concentration (C free ) to reliably (r 2  = 0.94) predict root uptake. Concentration in leaves did not exceed the maximum residue levels (MRLs) for lettuce, which was likely given by the low root-to-shoot translocation factors (TFs) of the tested compounds varying between 0.007 and 0.14. K oc values were in the range of literature values. Sorption to soil was higher than to sand for all compounds, yet following the K oc dynamics compounds did not appear to be sequestered in soil with increasing residence time. From these results, it follows that the tested compounds may persist in soil but since they did not accumulate in lettuce above MRLs, contamination of the food web is unlikely. Copyright © 2018 Elsevier Ltd. All rights reserved.

  19. Arsenic distribution in soils and rye plants of a cropland located in an abandoned mining area

    Energy Technology Data Exchange (ETDEWEB)

    Álvarez-Ayuso, Esther, E-mail: esther.alvarez@irnasa.csic.es [Department of Environmental Geochemistry, IRNASA (CSIC), C/ Cordel de Merinas 40-52, 37008 Salamanca (Spain); Abad-Valle, Patricia [Department of Environmental Geochemistry, IRNASA (CSIC), C/ Cordel de Merinas 40-52, 37008 Salamanca (Spain); Murciego, Ascensión [Department of Geology, Plza. de los Caídos s/n, Salamanca University, 37008 Salamanca (Spain); Villar-Alonso, Pedro [Saloro SLU, Avda. Italia 8, 37006 Salamanca (Spain)

    2016-01-15

    A mining impacted cropland was studied in order to assess its As pollution level and the derived environmental and health risks. Profile soil samples (0–50 cm) and rye plant samples were collected at different distances (0–150 m) from the near mine dump and analyzed for their As content and distribution. These cropland soils were sandy, acidic and poor in organic matter and Fe/Al oxides. The soil total As concentrations (38–177 mg kg{sup −1}) and, especially, the soil soluble As concentrations (0.48–4.1 mg kg{sup −1}) importantly exceeded their safe limits for agricultural use of soils. Moreover, the soil As contents more prone to be mobilized could rise up to 25–69% of total As levels as determined using (NH{sub 4}){sub 2}SO{sub 4}, NH{sub 4}H{sub 2}PO{sub 4} and (NH{sub 4}){sub 2}C{sub 2}O{sub 4}·H{sub 2}O as sequential extractants. Arsenic in rye plants was primarily distributed in roots (3.4–18.8 mg kg{sup −1}), with restricted translocation to shoots (TF = 0.05–0.26) and grains (TF = < 0.02–0.14). The mechanism for this excluder behavior should be likely related to arsenate reduction to arsenite in roots, followed by its complexation with thiols, as suggested by the high arsenite level in rye roots (up to 95% of the total As content) and the negative correlation between thiol concentrations in rye roots and As concentrations in rye shoots (| R | = 0.770; p < 0.01). Accordingly, in spite of the high mobile and mobilizable As contents in soils, As concentrations in rye above-ground tissues comply with the European regulation on undesirable substances in animal feed. Likewise, rye grain As concentrations were below its maximum tolerable concentration in cereals established by international legislation. - Highlights: • Environmental assessment of a rye cultivated area impacted by past mining activities. • Soil As contents exceeded the recommended safe limits for agricultural use of soils. • Soil soluble As concentrations attained high

  20. Bioavailability of Zn in ZnO nanoparticle-spiked soil and the implications to maize plants

    International Nuclear Information System (INIS)

    Liu, Xueqin; Wang, Fayuan; Shi, Zhaoyong; Tong, Ruijian; Shi, Xiaojun

    2015-01-01

    Little is known about the relationships between Zn bioavailability in ZnO nanoparticle (NP)-spiked soil and the implications to crops. The present pot culture experiment studied Zn bioavailability in soil spiked with different doses of ZnO NPs, using the diethylenetriaminepentaacetic acid (DTPA) extraction method, as well as the toxicity and Zn accumulation in maize plants. Results showed that ZnO NPs exerted dose-dependent effects on maize growth and nutrition, photosynthetic pigments, and root activity (dehydrogenase), ranging from stimulatory (100–200 mg/kg) through to neutral (400 mg/kg) and toxic effect (800–3200 mg/kg). Both Zn concentration in shoots and roots correlated positively (P < 0.01) with ZnO NPs dose and soil DTPA-extractable Zn concentration. The BCF of Zn in shoots and roots ranged from 1.02 to 3.83 when ZnO NPs were added. In most cases, the toxic effects on plants elicited by ZnO NPs were overall similar to those caused by bulk ZnO and soluble Zn (ZnSO 4 ) at the same doses, irrespective of some significant differences suggesting a higher toxicity of ZnO NPs. Oxidative stress in plants via superoxide free radical production was induced by ZnO NPs at 800 mg/kg and above, and was more severe than the same doses of bulk ZnO and ZnSO 4 . Although significantly lower compared to bulk ZnO and ZnSO 4 , at least 16 % of the Zn from ZnO NPs was converted into DTPA-extractable (bioavailable) forms. The dissolved Zn 2+ from ZnO NPs may make a dominant contribution to their phytotoxicity. Although low amounts of ZnO NPs exhibited some beneficial effects, the accumulation of Zn from ZnO NPs into maize tissues could pose potential health risks for both plants and human

  1. Saturated hydraulic conductivity model computed from bimodal water retention curves for a range of New Zealand soils

    Directory of Open Access Journals (Sweden)

    J. A. P. Pollacco

    2017-06-01

    Full Text Available Descriptions of soil hydraulic properties, such as the soil moisture retention curve, θ(h, and saturated hydraulic conductivities, Ks, are a prerequisite for hydrological models. Since the measurement of Ks is expensive, it is frequently derived from statistical pedotransfer functions (PTFs. Because it is usually more difficult to describe Ks than θ(h from pedotransfer functions, Pollacco et al. (2013 developed a physical unimodal model to compute Ks solely from hydraulic parameters derived from the Kosugi θ(h. This unimodal Ks model, which is based on a unimodal Kosugi soil pore-size distribution, was developed by combining the approach of Hagen–Poiseuille with Darcy's law and by introducing three tortuosity parameters. We report here on (1 the suitability of the Pollacco unimodal Ks model to predict Ks for a range of New Zealand soils from the New Zealand soil database (S-map and (2 further adaptations to this model to adapt it to dual-porosity structured soils by computing the soil water flux through a continuous function of an improved bimodal pore-size distribution. The improved bimodal Ks model was tested with a New Zealand data set derived from historical measurements of Ks and θ(h for a range of soils derived from sandstone and siltstone. The Ks data were collected using a small core size of 10 cm diameter, causing large uncertainty in replicate measurements. Predictions of Ks were further improved by distinguishing topsoils from subsoil. Nevertheless, as expected, stratifying the data with soil texture only slightly improved the predictions of the physical Ks models because the Ks model is based on pore-size distribution and the calibrated parameters were obtained within the physically feasible range. The improvements made to the unimodal Ks model by using the new bimodal Ks model are modest when compared to the unimodal model, which is explained by the poor accuracy of measured total porosity. Nevertheless, the new bimodal

  2. Saturated hydraulic conductivity model computed from bimodal water retention curves for a range of New Zealand soils

    Science.gov (United States)

    Pollacco, Joseph Alexander Paul; Webb, Trevor; McNeill, Stephen; Hu, Wei; Carrick, Sam; Hewitt, Allan; Lilburne, Linda

    2017-06-01

    Descriptions of soil hydraulic properties, such as the soil moisture retention curve, θ(h), and saturated hydraulic conductivities, Ks, are a prerequisite for hydrological models. Since the measurement of Ks is expensive, it is frequently derived from statistical pedotransfer functions (PTFs). Because it is usually more difficult to describe Ks than θ(h) from pedotransfer functions, Pollacco et al. (2013) developed a physical unimodal model to compute Ks solely from hydraulic parameters derived from the Kosugi θ(h). This unimodal Ks model, which is based on a unimodal Kosugi soil pore-size distribution, was developed by combining the approach of Hagen-Poiseuille with Darcy's law and by introducing three tortuosity parameters. We report here on (1) the suitability of the Pollacco unimodal Ks model to predict Ks for a range of New Zealand soils from the New Zealand soil database (S-map) and (2) further adaptations to this model to adapt it to dual-porosity structured soils by computing the soil water flux through a continuous function of an improved bimodal pore-size distribution. The improved bimodal Ks model was tested with a New Zealand data set derived from historical measurements of Ks and θ(h) for a range of soils derived from sandstone and siltstone. The Ks data were collected using a small core size of 10 cm diameter, causing large uncertainty in replicate measurements. Predictions of Ks were further improved by distinguishing topsoils from subsoil. Nevertheless, as expected, stratifying the data with soil texture only slightly improved the predictions of the physical Ks models because the Ks model is based on pore-size distribution and the calibrated parameters were obtained within the physically feasible range. The improvements made to the unimodal Ks model by using the new bimodal Ks model are modest when compared to the unimodal model, which is explained by the poor accuracy of measured total porosity. Nevertheless, the new bimodal model provides an

  3. Shoot growth of Merlot and Cabernet Sauvignon grapevine varieties

    OpenAIRE

    Marcelo Borghezan; Olavo Gavioli; Hamilton Justino Vieira; Aparecido Lima da Silva

    2012-01-01

    The objective of this work was to evaluate shoot growth of the grapevine varieties Merlot and Cabernet Sauvignon, during 2006/2007, and Cabernet Sauvignon, during 2008/2009, in São Joaquim, SC, Brazil. The experiment was carried out in a commercial vineyard trained on a vertical trellis system. The shoots of the central part of the plants were selected, and the lengths from the base to the apex of 20 shoots per cultivar were evaluated. In 2006/2007, monitoring began at pruning, on 9/15/2006, ...

  4. Effects of EDTA on phytoextraction of heavy metals (Zn, Mn and Pb) from sludge-amended soil with Brassica napus.

    Science.gov (United States)

    Zaier, Hanen; Ghnaya, Tahar; Ben Rejeb, Kilani; Lakhdar, Abdelbasset; Rejeb, Salwa; Jemal, Fatima

    2010-06-01

    Sludge application is a reliable practice to ameliorate soil fertility. However, repetitive sludge addition represents a potential soil contamination source with heavy metals, which must be extracted. The aim of this study was to evaluate the capacity of Brassica napus to remove metals from soils amended with sludge, and to study the effect of EDTA on this process. Seedlings were cultivated in presence of sludge combined or not with EDTA. Results showed that sludge ameliorate significantly biomass production. This effect was accompanied with an increase in Pb, Zn and Mn shoot concentrations. EDTA application does not affect significantly plant growth. However, this chelator enhances shoot metals accumulation. It's therefore concluded that sludge has a beneficial effect on soil fertility, B. napus can be used for the decontamination of affected soils and that the EDTA addition increases the ability of B. napus to accumulate heavy metals. Published by Elsevier Ltd.

  5. Effects of native and exotic range-expanding plant species on taxonomic and functional composition of nematodes in the soil food web

    NARCIS (Netherlands)

    Morrien, E.; Duyts, H.; Van der Putten, W.H.

    2012-01-01

    Due to climate warming, many plant species shift ranges towards higher latitudes. Plants can disperse faster than most soil biota, however, little is known about how range-expanding plants in the new range will establish interactions with the resident soil food web. In this paper we examine how the

  6. Comparative proteomics reveals the physiological differences between winter tender shoots and spring tender shoots of a novel tea (Camellia sinensis L.) cultivar evergrowing in winter.

    Science.gov (United States)

    Liu, Shengjie; Gao, Jiadong; Chen, Zhongjian; Qiao, Xiaoyan; Huang, Hualin; Cui, Baiyuan; Zhu, Qingfeng; Dai, Zhangyan; Wu, Hualing; Pan, Yayan; Yang, Chengwei; Liu, Jun

    2017-11-20

    A recently discovered tea [Camellia sinensis (L.) O. Kuntze] cultivar can generate tender shoots in winter. We performed comparative proteomics to analyze the differentially accumulated proteins between winter and spring tender shoots of this clonal cultivar to reveal the physiological basis of its evergrowing character during winter. We extracted proteins from the winter and spring tender shoots (newly formed two leaves and a bud) of the evergrowing tea cultivar "Dongcha11" respectively. Thirty-three differentially accumulated high-confidence proteins were identified by matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF / TOF MS). Among these, 24 proteins had increased abundance while nine showed were decreased abundance in winter tender shoots as compared with the spring tender shoots. We categorized the differentially accumulated proteins into eight critical biological processes based on protein function annotation including photosynthesis, cell structure, protein synthesis & destination, transporters, metabolism of sugars and polysaccharides, secondary metabolism, disease/defense and proteins with unknown functions. Proteins with increased abundance in winter tender shoots were mainly related to the processes of photosynthesis, cytoskeleton and protein synthesis, whereas those with decreased abundance were correlated to metabolism and the secondary metabolism of polyphenolic flavonoids. Biochemical analysis showed that the total contents of soluble sugar and amino acid were higher in winter tender shoots while tea polyphenols were lower as compared with spring tender shoots. Our study suggested that the simultaneous increase in the abundance of photosynthesis-related proteins rubisco, plastocyanin, and ATP synthase delta chain, metabolism-related proteins eIF4 and protease subunits, and the cytoskeleton-structure associated proteins phosphatidylinositol transfer protein and profilin may be because of the adaptation of the

  7. Uptake of radiocesium by three plants grown in 134Cs contaminated soil under pot experiment condition

    International Nuclear Information System (INIS)

    Zheng Jiemin; Li Hongyan; Niu Tianxin; Chen Ziyuan; Tang Shirong

    2009-01-01

    Pot experiment was conducted to investigate the accumulation dynamics of 134 Cs in shoots of Rumex acetosa, Rumex hastatus and Helianthus annuus grown in 134 Cs contaminated soil under greenhouse condition. Results showed that shoot biomass of H. annuus was significantly higher than that of R. acetosa and R. hastatus; among 3 plant species, 13 '4Cs specific activity in shoots was the highest in H. annuus after treatment for 50 days, however after treatment for 70 days, that in R. acetosa was the highest. Bioaccumulation ratio reached 1.5, 1.4 and 1.3 in R. acetosa, R. hastatus and H. annuus at the end of experiment, respectively, and the former two plants kept with trend of continuously increasing during the experiment period. Three plants were tolerant to 134 Cs contaminated slil and capable to translocate 134 Cs from soil to plants. Among them, H. annuus removed greatest 134 Cs amount in the above ground part, and R. acetosa, R. hastatus showed higher tranclocation factor of Cs than H. annuus. Three plants are promising for phytoremediation of soil contaminated with radiocesium, and also could be used for phytoremediation of radiocesium and heavy metals complex contamination, potentially. (authors)

  8. Bringing sexy back: reclaiming the body aesthetic via self-shooting

    DEFF Research Database (Denmark)

    Tiidenberg, Katrin

    2014-01-01

    ’s ‘technologies of the self’ to analyze self-shooting (taking photos of one-self). Constricting societal norms of sexuality, body shape and body practices influence how my participants (N=20, 10 female, 9 male, 1 transgender, ages 21 - 51, average age 34) live their embodied and sexual lives. Through self-shooting...... and by negotiating the community specific issues of control, power and the gaze, they are able to construct a new, empowered, embodied identity for themselves. I look at self-shooting and selfie-blogging as a practice of reclaiming control over one’s embodied self AND over the body-aesthetic, thus appropriating what...... is and is not ‘sexy’. The NSFW self-shooting community offers a safe space otherwise so hard to find within the body/sexuality-normative mainstream culture. This makes self-shooting a collective therapeutic activity. In their self-images participants construct themselves as ‘beautiful’, ‘sexy’, ‘devious’, ‘more than...

  9. Modeling Short-Range Soil Variability and its Potential Use in Variable-Rate Treatment of Experimental Plots

    Directory of Open Access Journals (Sweden)

    A Moameni

    2011-02-01

    Full Text Available Abstract In Iran, the experimental plots under fertilizer trials are managed in such a way that the whole plot area uniformly receives agricultural inputs. This could lead to biased research results and hence to suppressing of the efforts made by the researchers. This research was conducted in a selected site belonging to the Gonbad Agricultural Research Station, located in the semiarid region, northeastern Iran. The aim was to characterize the short-range spatial variability of the inherent and management-depended soil properties and to determine if this variation is large and can be managed at practical scales. The soils were sampled using a grid 55 m apart. In total, 100 composite soil samples were collected from topsoil (0-30 cm and were analyzed for calcium carbonate equivalent, organic carbon, clay, available phosphorus, available potassium, iron, copper, zinc and manganese. Descriptive statistics were applied to check data trends. Geostatistical analysis was applied to variography, model fitting and contour mapping. Sampling at 55 m made it possible to split the area of the selected experimental plot into relatively uniform areas that allow application of agricultural inputs with variable rates. Keywords: Short-range soil variability, Within-field soil variability, Interpolation, Precision agriculture, Geostatistics

  10. The Effect of High School Shootings on Schools and Student Performance

    Science.gov (United States)

    Beland, Louis-Philippe; Kim, Dongwoo

    2016-01-01

    We analyze how fatal shootings in high schools affect schools and students using data from shooting databases, school report cards, and the Common Core of Data. We examine schools' test scores, enrollment, number of teachers, graduation, attendance, and suspension rates at schools that experienced a shooting, employing a difference-in-differences…

  11. Effect of silicon on reducing cadmium toxicity in durum wheat (Triticum turgidum L. cv. Claudio W.) grown in a soil with aged contamination

    Energy Technology Data Exchange (ETDEWEB)

    Rizwan, Muhammad, E-mail: rizwan@cerege.fr [Aix-Marseille Universite, Centre National de la Recherche Scientifique, Institut pour la Recherche et le Developpement, College de France, CEREGE (Centre Europeen de Recherche et d' Enseignement en Geosciences de l' Environnement), Europole mediterraneen de l' Arbois, BP 80, 13454 Aix-en-Provence, Cedex 4 (France); Meunier, Jean-Dominique, E-mail: meunier@cerege.fr [Aix-Marseille Universite, Centre National de la Recherche Scientifique, Institut pour la Recherche et le Developpement, College de France, CEREGE (Centre Europeen de Recherche et d' Enseignement en Geosciences de l' Environnement), Europole mediterraneen de l' Arbois, BP 80, 13454 Aix-en-Provence, Cedex 4 (France); and others

    2012-03-30

    Highlights: Black-Right-Pointing-Pointer Metal stress alleviation in wheat supplemented with amorphous Si (ASi). Black-Right-Pointing-Pointer Pot experiment with a metal-contaminated soil and increased doses of ASi. Black-Right-Pointing-Pointer Effects are observed both at the soil and the plant levels. Black-Right-Pointing-Pointer ASi increases plant biomass and Cd content in roots and decreases Cd in shoots. Black-Right-Pointing-Pointer ASi decreases soil-available Cd but is limiting for Si uptake. - Abstract: Agricultural soil contamination and subsequently crops still require alternative solutions to reduce associated environmental risks. The effects of silica application on alleviating cadmium (Cd) phytotoxicity in wheat plants were investigated in a 71-day pot experiment conducted with a historically contaminated agricultural soil. We used amorphous silica (ASi) that had been extracted from a diatomite mine for Si distribution at 0, 1, 10 and 15 ton ASi ha{sup -1}. ASi applications increased plant biomass and plant Si concentrations, reduced the available Cd in the soil and the Cd translocation to shoots, while Cd was more efficiently sequestrated in roots. But ASi is limiting for Si uptake by plants. We conclude that significant plant-available Si in soil contributes to decreased Cd concentrations in wheat shoots and could be implemented in a general scheme aiming at controlling Cd concentrations in wheat.

  12. Integrating soils and geomorphology in mountains - An example from the Front Range of Colorado

    Science.gov (United States)

    Birkeland, P.W.; Shroba, R.R.; Burns, S.F.; Price, A.B.; Tonkin, P.J.

    2003-01-01

    Soil distribution in high mountains reflects the impact of several soil-forming factors. Soil geomorphologists use key pedological properties to estimate ages of Quaternary deposits of various depositional environments, estimate long-term stability and instability of landscapes, and make inferences on past climatic change. Once the influence of the soil-forming factors is known, soils can be used to help interpret some aspects of landscape evolution that otherwise might go undetected. The Front Range of Colorado rises from the plains of the Colorado Piedmont at about 1700 m past a widespread, dissected Tertiary erosion surface between 2300 and 2800 m up to an alpine Continental Divide at 3600 to over 4000 m. Pleistocene valley glaciers reached the western edge of the erosion surface. Parent rocks are broadly uniform (granitic and gneissic). Climate varies from 46 cm mean annual precipitation (MAP) and 11 ??C mean annual temperature (MAT) in the plains to 102 cm and -4 ??C, respectively, near the range crest. Vegetation follows climate with grassland in the plains, forest in the mountains, and tundra above 3450 m. Soils reflect the bioclimatic transect from plains to divide: A/Bw or Bt/Bk or K (grassland) to A/E/Bw or Bt/C (forest) to A/Bw/C (tundra). Corresponding soil pH values decrease from 8 to less than 5 with increasing elevation. The pedogenic clay minerals dominant in each major vegetation zone are: smectite (grassland), vermiculite (forest), and 1.0-1.8 nm mixed-layer clays (tundra). Within the lower forested zone, the topographic factor (aspect) results in more leached, colder soils, with relatively thin O horizons, well-expressed E horizons and Bt horizons (Alfisols) on N-facing slopes, whereas soils with thicker A horizons, less developed or no E horizons, and Bw or Bt horizons (Mollisols) are more common on S-facing slopes. The topographic factor in the tundra results in soil patterns as a consequence of wind-redistributed snow and the amount of time it

  13. Microculture of western white pine (Pinus monticola) by induction of shoots on bud explants from 1- to 7-year-old trees.

    Science.gov (United States)

    Lapp, M S; Malinek, J; Coffey, M

    1996-04-01

    We developed a protocol for the production of shoots from bud explants from 1- to 7-year-old trees of western white pine (Pinus monticola Dougl.). The best explant was a 2-mm-thick cross-sectional slice of the early winter bud. Genotype of the donor tree was a significant factor affecting shoot production, but more than 80% of the genotypes tested produced shoots. Of the media tested, bud slices from 1- to 3-year-old trees grew best in Litvay's medium containing N(6)-benzyladenine in the range of 1 to 30 micro M, whereas bud slices from older trees grew best in Gupta and Durzan's DCR medium with zeatin riboside. Up to 400 shoots more than 3 mm in height were obtained from 100 bud-slice explants taken from 7-year-old western white pine trees.

  14. A simplified Excel® algorithm for estimating the least limiting water range of soils

    Directory of Open Access Journals (Sweden)

    Leão Tairone Paiva

    2004-01-01

    Full Text Available The least limiting water range (LLWR of soils has been employed as a methodological approach for evaluation of soil physical quality in different agricultural systems, including forestry, grasslands and major crops. However, the absence of a simplified methodology for the quantification of LLWR has hampered the popularization of its use among researchers and soil managers. Taking this into account this work has the objective of proposing and describing a simplified algorithm developed in Excel® software for quantification of the LLWR, including the calculation of the critical bulk density, at which the LLWR becomes zero. Despite the simplicity of the procedures and numerical techniques of optimization used, the nonlinear regression produced reliable results when compared to those found in the literature.

  15. Bioavailability of coated and uncoated ZnO nanoparticles to cucumber in soil with or without organic matter.

    Science.gov (United States)

    Moghaddasi, Sahar; Fotovat, Amir; Khoshgoftarmanesh, Amir Hossein; Karimzadeh, F; Khazaei, Hamid Reza; Khorassani, Reza

    2017-10-01

    There is a gap of knowledge for the fate, effects and bioavailability of coated and uncoated ZnO nanoparticles (NPs) in soil. Moreover, little is known about the effects of soil properties on effects of NPs on plants. In this study, the availability ZnO NPs in two soils with different organic matter content (one treated with cow manure (CM) and the other as untreated) was compared with their bulk particles. Results showed that coated and uncoated ZnO NPs can be more bioaccessible than their bulk counterpart and despite their more positive effects at low concentration (soil untreated with CM. The concentration of 1000mgkg -1 of ZnO NPs, decreased shoot dry biomass (52%) in the soil untreated with CM but increased shoot dry biomass (35%) in CM-treated soil compared to their bulk counterpart. In general, plants in the CM-treated soil showed higher Zn concentration in their tissues compared with those in untreated soil. The difference in shoot Zn concentration between CM-treated and untreated soil for NPs treatments was more than bulk particles treatment. This different percentage at 100mgkg -1 of bulk particles was 20.6% and for coated and uncoated NPs were 37% and 32%, respectively. Generally, the distribution of ZnO among Zn fractions in soil (exchangeable, the metal bound to carbonates, Fe-Mn oxides, organic matter and silicate minerals and the residual fraction) changed based on applied Zn concentration, Zn source and soil organic matter content. The root tip deformation under high concentration of NPs (1000mgkg -1 treatment ) was observed by light microscopy in plants at the soil untreated with CM. It seems that root tip deformation is one of the specific effects of NPs which in turn inhibits plant growth and nutrients uptake by root. The transmission electron microcopy image showed the aggregation of NPs inside the plant cytoplasm and their accumulation adjacent to the cell membrane. Copyright © 2017. Published by Elsevier Inc.

  16. In vitro shoot multiplication of Ziziphus spina-christi by shoot tip culture

    African Journals Online (AJOL)

    USER

    2010-02-08

    Feb 8, 2010 ... Key words: Clonal propagation, cidir, shoot tip culture, Ziziphus spina-christi (L.) Desf. INTRODUCTION. Ziziphus spina-christi (L.) Desf., locally known as cidir, is a multipurpose tree species belonging to the botanical family Rhamnaceae. It is an important cultivated tree and one of the few truly native tree ...

  17. Progress in assisted natural remediation of an arsenic contaminated agricultural soil

    International Nuclear Information System (INIS)

    Mench, Michel; Vangronsveld, Jaco; Beckx, Caroline; Ruttens, Ann

    2006-01-01

    A contaminated soil was collected in a field adjacent to a derelict As (III) smelter in Reppel (Bocholt, Belgium). A single soil treatment (% by soil weight) based on either iron grit (SS, 1%), beringite (B, 5%), or iron grit (1%) + beringite (5%) (BSS) was applied. Untreated and treated Reppel soils and a control soil were placed in lysimeters inside a greenhouse and cropped annually. The efficiency of soil treatments in decreasing As and metals in exposure sources and restoring soil functions was assessed 6 years after the treatments commenced. Decreases in extractable Cd, Mn, Zn and As occurred in the BSS soil. Only BSS treatment reduced both As and metal concentrations in leachates. BSS treatment produced best growth of lettuce and cabbage, the highest shoot and pod yields for dwarf bean, the lowest As, Cd and Zn concentrations in plant tissues, and partly restored Rhizobium nodulation on bean roots. The epigeic earthworm (Dendrobaena octaedra) could only survive in the BSS soil. Depurated living worms from the BSS soil had Cd concentration similar to those in control worms, but higher As, Ca, Fe, and Zn concentrations. Based on physiologically based extraction test (PBET), As bioaccessibility was reduced from 12% (untreated soil) to 7.4% (BSS) and 3% (SS), but only the SS treatment decreased the bioaccessibility of Cd (-30%) and Pb (-35%). The range of chemical and biological indicators suggested that BSS amendment was the most effective treatment for restoration of normal soil functions 6 years after initial treatment of the Reppel soil. - Restoration occurred in a contaminated soil six years after the combined application of iron grit and beringite

  18. Ship and Shoot

    Science.gov (United States)

    Woods, Ron

    2012-01-01

    Ron Woods shared incredibly valuable insights gained during his 28 years at the Kennedy Space Center (KSC) packaging Flight Crew Equipment for shuttle and ISS missions. In particular, Woods shared anecdotes and photos from various processing events. The moral of these stories and the main focus of this discussion were the additional processing efforts and effects related to a "ship-and-shoot" philosophy toward flight hardware.

  19. A Comparison of Frontal Theta Activity During Shooting among Biathletes and Cross-Country Skiers before and after Vigorous Exercise.

    Directory of Open Access Journals (Sweden)

    Harri Luchsinger

    Full Text Available Previous studies using electroencephalography (EEG to monitor brain activity have linked higher frontal theta activity to more focused attention and superior performance in goal-directed precision tasks. In biathlon, shooting performance requires focused attention after high-intensity cross-country skiing.To compare biathletes (serving as experts and cross-country skiers (novices and examine the effect of vigorous exercise on frontal theta activity during shooting.EEG frontal theta (4-7 Hz activity was compared between nine biathletes and eight cross-country skiers at comparable skiing performance levels who fired 100 shots on a 5-m indoor shooting range in quiescent condition followed by 20 shots after each of five 6-min high-intensity roller skiing sessions in the skating technique on a treadmill.Biathletes hit 80±14% and 81±10% before and after the roller skiing sessions, respectively. For the cross-country skiers these values were significantly lower than for the biathletes and amounted to 39±13% and 44±11% (p<0.01. Biathletes had on average 6% higher frontal theta activity during shooting as compared to cross-country skiers (F1,15 = 4.82, p = 0.044, but no significant effect of vigorous exercise on frontal theta activity in either of the two groups were found (F1,15 = 0.14, p = 0.72.Biathletes had significantly higher frontal theta activity than cross-country skiers during shooting, indicating higher focused attention in biathletes. Vigorous exercise did not decrease shooting performance or frontal theta activity during shooting in biathletes and cross-country skiers.

  20. Disentangling the intertwined genetic bases of root and shoot growth in Arabidopsis.

    Directory of Open Access Journals (Sweden)

    Marie Bouteillé

    Full Text Available Root growth and architecture are major components of plant nutrient and water use efficiencies and these traits are the matter of extensive genetic analysis in several crop species. Because root growth relies on exported assimilate from the shoot, and changes in assimilate supply are known to alter root architecture, we hypothesized (i that the genetic bases of root growth could be intertwined with the genetic bases of shoot growth and (ii that the link could be either positive, with alleles favouring shoot growth also favouring root growth, or negative, because of competition for assimilates. We tested these hypotheses using a quantitative genetics approach in the model species Arabidopsis thaliana and the Bay-0 × Shahdara recombinant inbred lines population. In accordance with our hypothesis, root and shoot growth traits were strongly correlated and most root growth quantitative trait loci (QTLs colocalized with shoot growth QTLs with positive alleles originating from either the same or the opposite parent. In order to identify regions that could be responsible for root growth independently of the shoot, we generated new variables either based on root to shoot ratios, residuals of root to shoot correlations or coordinates of principal component analysis. These variables showed high heritability allowing genetic analysis. They essentially all yielded similar results pointing towards two regions involved in the root--shoot balance. Using Heterogeneous Inbred Families (a kind of near-isogenic lines, we validated part of the QTLs present in these two regions for different traits. Our study thus highlights the difficulty of disentangling intertwined genetic bases of root and shoot growth and shows that this difficulty can be overcome by using simple statistical tools.

  1. Biochemical characterization of systemic bacteria in bananas, sensitivity to antibiotics and plant phytotoxicity during shoot proliferation

    Directory of Open Access Journals (Sweden)

    Janiffe Peres de Oliveira

    2016-04-01

    Full Text Available The objective of this work was to characterize the biochemically systemic bacterial isolated from banana plants, to evaluate the bacterial sensitivity to antibiotics, and to determine the phytotoxicity of banana shoots during in vitro proliferation. Systemic bacteria belonging to the Klebsiella and Aeromonas genera were isolated from the “Maravilha” (FHIA 01 AAAB, “Preciosa” (PV 4285 AAAB and “Thap Maeo” (AAB varieties and were then characterized. Tests of shoot sensitivity to antibiotics were performed, and the minimum inhibitory concentration (MIC and phytotoxic effects of selected antibiotics to plants were determined. Among the 20 antibiotics evaluated, the strains showed sensitivity to cefaclor, cefalexin, cefalotin, nalidixic acid, chloramphenicol, and vancomycin. However, during MIC determination, the best results were obtained with cefaclor, vancomycin or nalidixic acid alone in concentrations ranging from 512 to 1,024 mg L-1. In culture medium, cefaclor at 1,024 mg L-1 was the only antibiotic to affect the multiplication and the shoot survival in culture.

  2. Distribution of 14C in soil and rice plants following application of 14C - parathion to soil

    International Nuclear Information System (INIS)

    Andrea, M.M. de; Ruegg, E.F.

    1983-01-01

    Amount of residues of 14 C-parathion in soil rice plants after application of the insecticide to soil were determined in four systems studied during five weeks: pots of soil with and without plants and open or enclosed by a transparent cover. Measurements of amounts volatilized and 14 CO 2 evolution from the pesticide were made in closed system without plants. The bound residues in soil and plants were also determined. Results indicated that parathion half life in a Gley Humic soil was about two weeks. Very little radiocarbon was taken up by rice plants; of this, more was found in shoots of plants enclosed, probably by collection of the volatilized material by plants. About 6% and 4% of the 14 C-parathion were found as volatilized material and 14 CO 2 , respectively after five weeks. Bound residues varied very little and reached a maximum of 22% in soil and in plants amounted to less than 2% at the final of the experiment. (Author) [pt

  3. Engineering of Soil Biological Quality from Nickel Mining Stockpile Using Two Earthworm Ecological Groups

    Directory of Open Access Journals (Sweden)

    L M H Kilowasid

    2015-04-01

    Full Text Available Earthworms have the ability in modifying soil biological quality for plant growth. Their ability is mostly depending on its ecological groups. The objectives of the research were to study the influence of two ecological groups of earthworms on soil microbial activity and soil micro-fauna abundance, and to know the potential of soil modified by earthworms as plant growth medium. Eight combination of individual earthworm from epigeic and endogeic groups was applied into pot that was filled by soil from two years of nickel stockpile and each treatment was repeated by five times. The experiment was following complete randomize design procedure. After sixteen days of research, the soil sample from each pot was analyzed for soil FDA activity, number of flagellate and nematodes. Furthermore, one kg of the soil from each pot was taken and every pot was grown by Paraserianthes falcataria seedling with the age of five days and continued its growth for two months. The results indicated that the soil FDA activity, number of flagellate and nematodes among treatments were significantly differences. In addition, it indicated the significant differences in dry weight of shoot, root, total plant, and root to shoot ratio of P. falcataria seedlings. It concluded that the combination of an individual number of epigeic and endogeic earthworms improved soil biological quality of stock pile, amd most suitable for seedlings growth in nickel mining area.

  4. A feasibility test to estimate the duration of phytoextraction of heavy metals from polluted soils.

    Science.gov (United States)

    Japenga, J; Koopmans, G F; Song, J; Römkens, P F A M

    2007-01-01

    The practical applicability of heavy metal (HM) phytoextraction depends heavily on its duration. Phytoextraction duration is the main cost factorfor phytoextraction, both referring to recurring economic costs during phytoextraction and to the cost of the soil having no economic value during phytoextraction. An experiment is described here, which is meant as a preliminary feasibility test before starting a phytoextraction scheme in practice, to obtain a more realistic estimate of the phytoextraction duration of a specific HM-polluted soil. In the experiment, HM-polluted soil is mixed at different ratios with unpolluted soil of comparable composition to mimic the gradual decrease of the HM content in the target HM-polluted soil during phytoextraction. After equilibrating the soil mixtures, one cropping cycle is carried out with the plant species of interest. At harvest, the adsorbed HM contents in the soil and the HM contents in the plant shoots are determined. The adsorbed HM contents in the soil are then related to the HM contents in the plant shoots by a log-log linear relationship that can then be used to estimate the phytoextraction duration of a specific HM-polluted soil. This article describes and evaluates the merits of such a feasibility experiment. Potential drawbacks regarding the accuracy of the described approach are discussed and a greenhouse-field extrapolation procedure is proposed.

  5. Copper phytoextraction in tandem with oilseed production using commercial cultivars and mutant lines of sunflower.

    Science.gov (United States)

    Kolbas, A; Mench, M; Herzig, R; Nehnevajova, E; Bes, C M

    2011-01-01

    Use of sunflower (Helianthus annuus L.) for Cu phytoextraction and oilseed production on Cu-contaminated topsoils was investigated in afield trial at a former wood preservation site. Six commercial cultivars and two mutant lines were cultivated in plots with and without the addition of compost (5% w/w) and dolomitic limestone (0.2% w/w). Total soil Cu ranged from 163 to 1170 mg kg(-1). In soil solutions, Cu concentration varied between 0.16-0.93 mg L(-1). The amendment increased soil pH, reduced Cu exposure and promoted sunflower growth. Stem length, shoot and capitulum biomasses, seed yield, and shoot and leaf Cu concentrations were measured. At low total soil Cu, shoot Cu mineralomass was higher in commercial cultivars, Le., Salut, Energic, and Countri, whereas competition and shading affected morphological traits of mutants. Based on shoot yield (7 Mg DW ha(-1)) and Cu concentration, the highest removal was 59 g Cu ha(-1). At high total soil Cu, shoot Cu mineralomass peaked for mutants (e.g., 52 g Cu ha(-1) for Mutant 1 line) and cultivars Energic and Countri. Energic seed yield (3.9 Mg air-DW ha(-1)) would be sufficient to produce oil Phenotype traits and shoot Cu removal depended on sunflower types and Cu exposure.

  6. Can arbuscular mycorrhizal fungi reduce Cd uptake and alleviate Cd toxicity of Lonicera japonica grown in Cd-added soils?

    Science.gov (United States)

    Jiang, Qiu-Yun; Zhuo, Feng; Long, Shi-Hui; Zhao, Hai-Di; Yang, Dan-Jing; Ye, Zhi-Hong; Li, Shao-Shan; Jing, Yuan-Xiao

    2016-02-01

    A greenhouse pot experiment was conducted to study the impact of arbuscular mycorrhizal fungi-Glomus versiforme (Gv) and Rhizophagus intraradices (Ri) on the growth, Cd uptake, antioxidant indices [glutathione reductase (GR), ascorbate peroxidase (APX), superoxide dismutase (SOD), catalase (CAT), ascorbate (ASA), glutathione (GSH) and malonaldehyde (MDA)] and phytochelatins (PCs) production of Lonicera japonica in Cd-amended soils. Gv and Ri significantly increased P acquisition, biomass of shoots and roots at all Cd treatments. Gv significantly decreased Cd concentrations in shoots and roots, and Ri also obviously reduced Cd concentrations in shoots but increased Cd concentrations in roots. Meanwhile, activities of CAT, APX and GR, and contents of ASA and PCs were remarkably higher in Gv/Ri-inoculated plants than those of uninoculated plants, but lower MDA and GSH contents in Gv/Ri-inoculated plants were found. In conclusion, Gv and Ri symbiosis alleviated Cd toxicity of L. japonica through the decline of shoot Cd concentrations and the improvement of P nutrition, PCs content and activities of GR, CAT, APX in inoculated plants, and then improved plant growth. The decrease of shoot Cd concentrations in L. japonica inoculated with Gv/Ri would provide a clue for safe production of this plant from Cd-contaminated soils.

  7. [Bidens maximowicziana's adsorption ability and remediation potential to lead in soils].

    Science.gov (United States)

    Wang, Hong-qi; Li, Hua; Lu, Si-jin

    2005-11-01

    Bidens maximowicziana's adsorption ability and remediation potential to lead were studied. The results show: (1) The Bidens maximowicziana has a strong adsorption to lead, the concentration of lead in plants increased linearly with the increase of lead concentration in soil. Then maximum concentration was 1509.3 mg x kg(-1) in roots and 2164.7 mg x kg(-1) in shoots when lead concentration in soil was 2000 mg x L(-1); (2) The lead concentration distribution order in the Bidens maximorwicziana is: leaf>stem>root>seed, which indicate that Bidens maximowicziana has a strong ability to transfer lead; (3) Uptaking ability differes in different vegetal periods. Maximum lead uptaking rate occured in the period of blooming for 40-60 days, in which daily uptake capacity was 15.81 mg x (kg x d)(-1) in roots and 19.83 mg x (kg x d)(-1) in shoots respectively. It can be concluded that Bidens maximowicziana appeares to be a moderate Pb accumulator making it suitable for phytoremediation of Pb contaminated soil.

  8. Prosopis juliflora--a green solution to decontaminate heavy metal (Cu and Cd) contaminated soils.

    Science.gov (United States)

    Senthilkumar, P; Prince, W S P M; Sivakumar, S; Subbhuraam, C V

    2005-09-01

    Soil and plant samples (root and shoot) of Prosopis juliflora were collected in the vicinity of metal based foundry units in Coimbatore and assessed for their heavy metal content (Cu and Cd) to ascertain the use of P. juliflora as a green solution to decontaminate soils contaminated with Cu and Cd. The results showed that Cu and Cd content was much higher in plant components compared to their extractable level in the soil. Furthermore, there exist a strong correlation between the distance of the sources of industrial units and accumulation of heavy metals in plants. Accumulation of Cd in roots is comparatively higher than that of shoots. However, in case of Cu no such clear trend is seen. Considering the accumulation efficiency and tolerance of P. juliflora to Cd and Cu, this plant can be explored further for the decontamination of metal polluted soils. On the other hand, in view of heavy metal accumulate the practice of providing foliage and pods as fodder for live stock should be avoided.

  9. Highly efficient in vitro adventitious shoot regeneration of Adenosma ...

    African Journals Online (AJOL)

    Adenosma glutinosum (Linn.) Druce is an important aromatic plant, but no information is available regarding its regeneration, callus induction and proliferation from leaf explants. In this study, an in vitro shoot regeneration procedure was developed for native A. glutinosum using leaf explants. Callus induction and shoots ...

  10. Soil fluoride spiking effects on olive trees (Olea europaea L. cv. Chemlali).

    Science.gov (United States)

    Zouari, M; Ben Ahmed, C; Fourati, R; Delmail, D; Ben Rouina, B; Labrousse, P; Ben Abdallah, F

    2014-10-01

    A pot experiment under open air conditions was carried out to investigate the uptake, accumulation and toxicity effects of fluoride in olive trees (Olea europaea L.) grown in a soil spiked with inorganic sodium fluoride (NaF). Six different levels (0, 20, 40, 60, 80 and 100mM NaF) of soil spiking were applied through NaF to irrigation water. At the end of the experiment, total fluoride content in soil was 20 and 1770mgFkg(-1) soil in control and 100mM NaF treatments, respectively. The comparative distribution of fluoride partitioning among the different olive tree parts showed that the roots accumulated the most fluoride and olive fruits were minimally affected by soil NaF spiking as they had the lowest fluoride content. In fact, total fluoride concentration varied between 12 and 1070µgFg(-1) in roots, between 9 and 570µgFg(-1) in shoots, between 12 and 290µgFg(-1) in leaves, and between 10 and 29µgFg(-1) in fruits, respectively for control and 100mM NaF treatments. Indeed, the fluoride accumulation pattern showed the following distribution: roots>shoots>leaves>fruits. On the other hand, fluoride toxicity symptoms such as leaf necrosis and leaf drop appeared only in highly spiked soils (60, 80 and 100mM NaF). Copyright © 2014 Elsevier Inc. All rights reserved.

  11. Phytoextraction of Pb and Cu contaminated soil with maize and microencapsulated EDTA.

    Science.gov (United States)

    Xie, Zhiyi; Wu, Longhua; Chen, Nengchang; Liu, Chengshuai; Zheng, Yuji; Xu, Shengguang; Li, Fangbai; Xu, Yanling

    2012-09-01

    Chelate-assisted phytoextraction using agricultural crops has been widely investigated as a remediation technique for soils contaminated with low mobility potentially toxic elements. Here, we report the use of a controlled-release microencapsulated EDTA (Cap-EDTA) by emulsion solvent evaporation to phytoremediate soil contaminated with Pb and Cu. Incubation experiments were carried out to assess the effect of Cap- and non-microencapsulated EDTA (Ncap-EDTA) on the mobility of soil metals. Results showed EDTA effectively increased the mobility of Pb and Cu in the soil solution and Cap-EDTA application provided lower and more constant water-soluble concentrations of Pb and Cu in comparison with. Phytotoxicity may be alleviated and plant uptake of Pb and Cu may be increased after the incorporation of Cap-EDTA. In addition phytoextraction efficiencies of maize after Cap- and Ncap-EDTA application were tested in a pot experiment. Maize shoot concentrations of Pb and Cu were lower with Cap-EDTA application than with Ncap-EDTA. However, shoot dry weight was significantly higher with Cap-EDTA application. Consequently, the Pb and Cu phytoextraction potential of maize significantly increased with Cap-EDTA application compared with the control and Ncap-EDTA application.

  12. Structuring agreements for seismic group shoots

    International Nuclear Information System (INIS)

    Keeping, C.E.

    1999-01-01

    Sigma Explorations Inc. sells licenses to use Sigma owned seismic data. The company participates with exploration and production companies in the joint acquisition of semi-private participation surveys. This paper discusses three major types of seismic group shoots and the essential elements of the agreements that govern or should govern them. They are: (1) exploration and production company joint ventures, (2) publicly offered spec shoots, and (3) semi-private participation surveys. The key issue with the exploration and production company joint ventures is that the companies are owners of the seismic data in proportion to their contribution towards the cost of the program. Their use of the data should be restricted to those situations permitted by the other owners. These are not often well documented, and there is much concern in the industry as a result. The key issue with publicly offered spec shoots is that the seismic company ultimately owns the data and the client exploration and production company is a licensee and must behave as such. In most such cases the rights and responsibilities are well documented in formal agreements that are signed in advance of the program's beginning date

  13. Impacts of Steel-Slag-Based Silicate Fertilizer on Soil Acidity and Silicon Availability and Metals-Immobilization in a Paddy Soil.

    Directory of Open Access Journals (Sweden)

    Dongfeng Ning

    Full Text Available Slag-based silicate fertilizer has been widely used to improve soil silicon- availability and crop productivity. A consecutive early rice-late rice rotation experiment was conducted to test the impacts of steel slag on soil pH, silicon availability, rice growth and metals-immobilization in paddy soil. Our results show that application of slag at a rate above higher or equal to 1 600 mg plant-available SiO2 per kg soil increased soil pH, dry weight of rice straw and grain, plant-available Si concentration and Si concentration in rice shoots compared with the control treatment. No significant accumulation of total cadmium (Cd and lead (Pb was noted in soil; rather, the exchangeable fraction of Cd significantly decreased. The cadmium concentrations in rice grains decreased significantly compared with the control treatment. In conclusion, application of steel slag reduced soil acidity, increased plant-availability of silicon, promoted rice growth and inhibited Cd transport to rice grain in the soil-plant system.

  14. Interactions of rice (Oryza sativa L.) and PAH-degrading bacteria (Acinetobacter sp.) on enhanced dissipation of spiked phenanthrene and pyrene in waterlogged soil.

    Science.gov (United States)

    Gao, Y; Yu, X Z; Wu, S C; Cheung, K C; Tam, N F Y; Qian, P Y; Wong, M H

    2006-12-15

    The effects of cultivation of rice (Oryza sativa L.) and PAH-degrading bacteria (Acinetobacter sp.) separately, and in combination, on the dissipation of spiked phenanthrene and pyrene (0, 50+50, 100+100, 200+200 mg kg(-1)) in waterlogged soil were studied using pot trials. The population of introduced PAH-degrading bacteria remained at 10(5) CFU g(-1) dry soil after 20 days of treatment with Acinetobacter sp. only, but increased to 10(6) when planted with rice simultaneously. Shoot and root biomass of rice when grown alone was adversely affected by spiked PAHs, but significantly increased by 2-55% and 8-409%, respectively, when inoculated with Acinetobacter sp.. Phenanthrene and pyrene concentrations in roots ranged from 1-27 and 20-98 mg kg(-1), respectively, while their concentrations in shoots were generally lower than 0.2 mg kg(-1). The dissipation of phenanthrene was mainly due to abiotic loss as 70-78% phenanthrene was lost from the control soil at the end of 80 days, while removal of 86-87% phenanthrene had been achieved after 40 days in the treatment co-cultivated with Acinetobacter sp. and rice. Compared with the control where only 6-15% of pyrene was removed from soil, a much higher dissipation of pyrene (43-62%) was attained for the treatments co-cultivated with Acinetobacter sp. and rice at the end of 80 days. The results demonstrated that co-cultivation of rice and PAH-degrading bacteria may have a great potential to accelerate the bioremediation process of PAH-contaminated soil under waterlogged conditions.

  15. Phosphate application to firing range soils for Pb immobilization: The unclear role of phosphate

    International Nuclear Information System (INIS)

    Chrysochoou, Maria; Dermatas, Dimitris; Grubb, Dennis G.

    2007-01-01

    Phosphate treatment has emerged as a widely accepted approach to immobilize Pb in contaminated soils and waste media, relying on the formation of the highly insoluble mineral pyromorphite as solubility-controlling phase for Pb. As such, phosphate treatment has been proposed as a Best Management Practice (BMP) for firing ranges where Pb occurs in its metallic forms and several other phases (carbonates, oxides). While pyromorphite thermodynamically has the potential to control Pb solubility at low levels, its formation is kinetically controlled by pH, the solubility of the phosphate source, and the solubility of Pb species. Treatability studies have shown that excess quantities of soluble and acidic phosphate sources, such as phosphoric acid, are necessary for successful in situ treatment. Even under these conditions, Extended X-ray Absorption Fine Structure (EXAFS), the only reliable method to identify and quantify Pb speciation, showed that Pb conversion to pyromorphite in in situ treated soils was less than 45% after 32 months. Furthermore, the use of lime (CaO) to restore soil pH in acidified soil treatments inhibited further conversion. Additionally, phosphate treatment is known to reduce bioavailability through pyromorphite formation in the intestinal tract, and the phytoaccumulation of Pb; both desirable effects for Pb-impacted areas. Given the costs of phosphate treatment, the use of biogenic phosphate sources, such as bone meal, may be a more environmentally sustainable approach toward this end. In the many studies focusing on phosphate treatment, the attendant P leaching and eutrophication have been largely overlooked, along with other issues such as the enhanced leaching of oxyanionic contaminants, such as Se, As and W. The success and sustainability of applying phosphate as a BMP in firing range soils therefore remain questionable

  16. Water relations, gas exchange and growth of dominant and suppressed shoots of Arbutus unedo L.

    Science.gov (United States)

    Castell, C; Terradas, J

    1995-06-01

    Basal shoots produced by Arbutus unedo L. after cutting at ground level vary in size and growth rate, and are classified accordingly as dominant or suppressed. The suppressed shoots eventually cease growth and die. In this study, we investigated the role of light and water in the competition among shoots of A. unedo. Dominant and suppressed shoots of A. unedo showed similar leaf water potentials and tissue water relations over the year, suggesting that water status is not responsible for the lack of flushing in suppressed shoots. Although suppressed shoots did not flush under low light, they showed many characteristics of shade-tolerant plants. Leaves of suppressed shoots had lower leaf conductance and light-saturated photosynthetic rate, and higher specific leaf area than leaves of dominant shoots. We conclude that light was the main resource determining competition among shoots and the death of suppressed shoots.

  17. Hospital-based shootings in the United States: 2000 to 2011.

    Science.gov (United States)

    Kelen, Gabor D; Catlett, Christina L; Kubit, Joshua G; Hsieh, Yu-Hsiang

    2012-12-01

    Workplace violence in health care settings is a frequent occurrence. Emergency departments (EDs) are considered particularly vulnerable. Gunfire in hospitals is of particular concern; however, information about such workplace violence is limited. Therefore, we characterize US hospital-based shootings from 2000 to 2011. Using LexisNexis, Google, Netscape, PubMed, and ScienceDirect, we searched reports for acute care hospital shooting events in the United States for 2000 through 2011. All hospital-based shootings with at least 1 injured victim were analyzed. Of 9,360 search "hits," 154 hospital-related shootings were identified, 91 (59%) inside the hospital and 63 (41%) outside on hospital grounds. Shootings occurred in 40 states, with 235 injured or dead victims. Perpetrators were overwhelmingly men (91%) but represented all adult age groups. The ED environs were the most common site (29%), followed by the parking lot (23%) and patient rooms (19%). Most events involved a determined shooter with a strong motive as defined by grudge (27%), suicide (21%), "euthanizing" an ill relative (14%), and prisoner escape (11%). Ambient society violence (9%) and mentally unstable patients (4%) were comparatively infrequent. The most common victim was the perpetrator (45%). Hospital employees composed 20% of victims; physician (3%) and nurse (5%) victims were relatively infrequent. Event characteristics that distinguished the ED from other sites included younger perpetrator, more likely in custody, and unlikely to have a personal relationship with the victim (ill relative, grudge, coworker). In 23% of shootings within the ED, the weapon was a security officer's gun taken by the perpetrator. Case fatality inside the hospital was much lower in the ED setting (19%) than other sites (73%). Although it is likely that not every hospital-based shooting was identified, such events are relatively rare compared with other forms of workplace violence. The unpredictable nature of this type of

  18. Model Persamaan Massa Karbon Akar Pohon dan Root-Shoot Ratio Massa Karbon (Equation Models of Tree Root Carbon Mass and Root-Shoot Carbon Mass Ratio

    Directory of Open Access Journals (Sweden)

    Elias .

    2011-03-01

    Full Text Available The case study was conducted in the area of Acacia mangium plantation at BKPH Parung Panjang, KPH Bogor. The objective of the study was to formulate equation models of tree root carbon mass and root to shoot carbon mass ratio of the plantation. It was found that carbon content in the parts of tree biomass (stems, branches, twigs, leaves, and roots was different, in which the highest and the lowest carbon content was in the main stem of the tree and in the leaves, respectively. The main stem and leaves of tree accounted for 70% of tree biomass. The root-shoot ratio of root biomass to tree biomass above the ground and the root-shoot ratio of root biomass to main stem biomass was 0.1443 and 0.25771, respectively, in which 75% of tree carbon mass was in the main stem and roots of tree. It was also found that the root-shoot ratio of root carbon mass to tree carbon mass above the ground and the root-shoot ratio of root carbon mass to tree main stem carbon mass was 0.1442 and 0.2034, respectively. All allometric equation models of tree root carbon mass of A. mangium have a high goodness-of-fit as indicated by its high adjusted R2.Keywords: Acacia mangium, allometric, root-shoot ratio, biomass, carbon mass

  19. Correlation of arbuscular mycorrhizal colonization with plant growth, nodulation, and shoot npk in legumes

    International Nuclear Information System (INIS)

    Javaid, A.; Anjum, T.; Shah, M.H.M.

    2007-01-01

    Correlation of arbuscular mycorrhizal colonization with different root and shoot growth, nodulation and shoot NPK parameters was studied in three legumes viz. Trifolium alexandrianum, Medicago polymorpha and Melilotus parviflora. The three test legume species showed different patterns of root and shoot growth, nodulation, mycorrhizal colonization and shoot N, P and K content. Different mycorrhizal structures viz. mycelium, arbuscules and vesicles showed different patters of correlation with different studied parameters. Mycelial infection showed an insignificantly positive correlation with root and shoot dry biomass and total root length. Maximum root length was however, negatively associated with mycelial infection. Both arbuscular and vesicular infections were negatively correlated with shoot dry biomass and different parameters of root growth. The association between arbuscular infection and maximum root length was significant. All the three mycorrhizal structures showed a positive correlation with number and biomass of nodules. The association between arbuscular infection and nodule number was significant. Mycelial infection was positively correlated with percentage and total shoot N and P. Similarly percentage N was also positively correlated with arbuscular and vesicular infections. By contrast, total shoot N showed a negative association with arbuscular as well as vesicular infections. Similarly both percentage and total shoot P were negatively correlated with arbuscular and vesicular infections. All the associations between mycorrhizal parameters and shoot K were negative except between vesicular infection and shoot %K. (author)

  20. Mass shootings: a meta-analysis of the dose-response relationship.

    Science.gov (United States)

    Wilson, Laura C

    2014-12-01

    A meta-analysis was conducted to examine the dose-response theory as it relates to posttraumatic stress symptoms (PTSSs) following mass shootings. It was hypothesized that greater exposure to a mass shooting would be associated with greater PTSSs. Trauma exposure in the current study was broadly defined as the extent to which a person experienced or learned about a mass shooting. The meta-analysis identified 11 qualifying studies that included 13 independent effect sizes from a total of 8,047 participants. The overall weighted mean effect size, based on a random effects model, was r = .19, p shooting on the relationship between exposure and PTSSs. Because so few studies satisfied the inclusion criteria, the present study also documents that this area of the literature is underresearched. Copyright © 2014 International Society for Traumatic Stress Studies.

  1. Youth Responses to School Shootings: A Reviw

    DEFF Research Database (Denmark)

    Travers, Áine

    2018-01-01

    PURPOSE OF REVIEW:This paper aims to synthesize research relating to youth responses to school shootings between 2014 and 2017. The main questions it addresses are how such events impact young people psychologically, and what risk or protective factors may contribute to different trajectories...... of recovery? RECENT FINDINGS:Recent research suggests that most young people exposed to school shootings demonstrate resilience, exhibiting no long-term dysfunction. However, a minority will experience severe and chronic symptoms. The likelihood of experiencing clinically significant reactions is influenced...

  2. Effects of the mycorrhizal fungus ¤Glomus intraradices¤ on uranium uptake and accumulation by ¤Medicago truncatula¤ L. from uranium-contaminated soil

    DEFF Research Database (Denmark)

    Chen, B.D.; Jakobsen, I.; Roos, P.

    2005-01-01

    cultivation system facilitating the specific measurement of U uptake by roots, AM roots and extraradical hyphae of AM fungi and the measurement of U partitioning between root and shoot. A soil-filled plastic pot constituted the main root compartment (C-A) which contained a plastic vial filled with U......-contaminated soil amended with 0, 50 or 200 mg KH2PO4-P kg(-1) soil (C-B). The vial was sealed by coarse or fine nylon mesh, permitting the penetration of both roots and hyphae or of just hyphae. Medicago truncatula plants grown in C-A were inoculated with G. intraradices or remained uninoculated. Dry weight...... in C-A, but decreased shoot U concentrations. Root U concentrations and contents were significantly higher when only hyphae could access U inside C-B than when roots could also directly access this U pool. The proportion of plant U content partitioned to shoots was decreased by root exclusion from C...

  3. Long-range alpha detection applied to soil contamination and waste monitoring

    International Nuclear Information System (INIS)

    MacArthur, D.W.; Allander, K.S.; Bounds, J.A.; Close, D.A.; McAtee, J.L.

    1992-01-01

    Alpha contamination monitoring has been traditionally limited by the short range of alpha particles in air and through detector windows. The long-range alpha detector (LRAD) described in this paper circumvents that limitation by detecting alpha-produced ions, rather than alpha particles directly. Since the LRAD is sensitive to all ions, it can monitor all contamination present on a large surface at one time. Because air is the ''detector gas,'' the LRAD can detect contamination on any surface to which air can penetrate. We present data showing the sensitivity of LRAD detectors, as well as documenting their ability to detect alpha sources in previously unmonitorable locations, and verifying the ion lifetime. Specific designs and results for soil contamination and waste monitors are also included

  4. Efficient regeneration of plants from shoot tip explants of ...

    African Journals Online (AJOL)

    Dendrobium densiflorum Lindl. is one of the horticulturally important orchids of Nepal due to its beautiful yellowish flower and medicinal properties. The present study was carried out for plant regeneration from shoot tip explants of D. densiflorum by tissue culture technique. The shoot tip explants of this species, obtained ...

  5. Solubility of lead and copper in biochar-amended small arms range soils: influence of soil organic carbon and pH.

    Science.gov (United States)

    Uchimiya, Minori; Bannon, Desmond I

    2013-08-14

    Biochar is often considered a strong heavy metal stabilizing agent. However, biochar in some cases had no effects on, or increased the soluble concentrations of, heavy metals in soil. The objective of this study was to determine the factors causing some biochars to stabilize and others to dissolve heavy metals in soil. Seven small arms range soils with known total organic carbon (TOC), cation exchange capacity, pH, and total Pb and Cu contents were first screened for soluble Pb and Cu concentrations. Over 2 weeks successive equilibrations using weak acid (pH 4.5 sulfuric acid) and acetate buffer (0.1 M at pH 4.9), Alaska soil containing disproportionately high (31.6%) TOC had nearly 100% residual (insoluble) Pb and Cu. This soil was then compared with sandy soils from Maryland containing significantly lower (0.5-2.0%) TOC in the presence of 10 wt % (i) plant biochar activated to increase the surface-bound carboxyl and phosphate ligands (PS450A), (ii) manure biochar enriched with soluble P (BL700), and (iii) unactivated plant biochars produced at 350 °C (CH350) and 700 °C (CH500) and by flash carbonization (corn). In weak acid, the pH was set by soil and biochar, and the biochars increasingly stabilized Pb with repeated extractions. In pH 4.9 acetate buffer, PS450A and BL700 stabilized Pb, and only PS450A stabilized Cu. Surface ligands of PS450A likely complexed and stabilized Pb and Cu even under acidic pH in the presence of competing acetate ligand. Oppositely, unactivated plant biochars (CH350, CH500, and corn) mobilized Pb and Cu in sandy soils; the putative mechanism is the formation of soluble complexes with biochar-borne dissolved organic carbon. In summary, unactivated plant biochars can inadvertently increase dissolved Pb and Cu concentrations of sandy, low TOC soils when used to stabilize other contaminants.

  6. Effect of some soil amendments on soil properties and plant growth in Southern Thailand acid upland soil

    Directory of Open Access Journals (Sweden)

    Onthong, C.

    2007-01-01

    Full Text Available One of the major factors limiting plant growth is acid soil. In general lime is used for soil amendment in acid soil. However, It has been reported that gypsum or phosphogypsum can be used for ameliorating soilacidity. Pot experiment was conducted to study the effects of lime, phosphogypsum and kieserite on soil properties and plant growth in Kho Hong soil series (coarse loamy, kaolinitic,isohyperthermic, TypicKandiudults which was considered as acid upland soil (pH 5.07. Sweet corn variety INSEE 2 was used as the test crop. The experiment was a completely randomized design with 4 replications and 19 treatments asfollow : unamended, application of hydrated lime and dolomite to raise soil pH at 5.5, application of hydrated lime and dolomite combined with phosphogypsum at the rate that can supply calcium 0.25, 0.50,0.75 and 1 time of both limes, application of hydrated lime and dolomite combined with kieserite at the rate 0.25, 0.50,0.75 and 1 times of sulfur requirement for corn (40 kg S ha-1. The result showed that shoot and root dry weights of corn were increased when lime materials, phosphogypsum and kieserite were applied and the drymatter weights were increased according to the increasing of phosphogypsum and kieserite. The maximum shoot dry weight (18.98 g pot-1 was obtained when 1 times of kieserite was supplied with dolomite and wassignificantly (P<0.01 higher than those of the unamended treatment, only hydrated lime and dolomite treatments, which had dry weights of 12.64, 15.18 and 15.67 g pot-1 respectively. Phosphorus and K uptakewere not significantly different in all treatments and the lowest uptake of N, Ca, Mg and S was obtained in the unamended treatment. The maximum uptake of N (512.10 mg pot-1 was found when 0.5 times ofphosphogypsum was applied together with dolomite. Calcium and Mg uptake was likely to increase according to the increasing rate of soil amendment application. Highest uptake of Ca (42.51 mg pot-1 was obtainedwhen

  7. Reduction of Cadmium Uptake of Rice Plants Using Soil Amendments in High Cadmium Contaminated Soil: A Pot Experiment

    Directory of Open Access Journals (Sweden)

    Dian Siswanto

    2013-05-01

    Full Text Available The aims of this study were to investigate the effect of agricultural residues on reducing cadmium uptake in rice plants. The rice plants growing on no cadmium/free cadmium soils (N, Cd soils (Cds, and Cd soils each amended with 1% w/w of coir pith (CP, coir pith modified with sodium hydroxide (CPm and corncob (CC under high cadmium contaminated soil with an average 145 mg Cd kg-1 soil were investigated. The results showed that the cumulative transpiration of rice grown in various treatments under high cadmium contaminated soil followed the order: Cds > CPm ≥ CP ≥ CC. These transpirations directly influenced cadmium accumulation in shoots and husks of rice plants. The CC and CP seemed to work to reduce the cadmium uptake by rice plants indicated by accumulated cadmium in the husk that were 2.47 and 7.38 mg Cd kg-1 dry weight, respectively. Overall, transpiration tended to drive cadmium accumulation in plants for rice grown in high cadmium contaminated soil. The more that plants uptake cadmium, the lower cadmium that remains in the soil.

  8. Metabolomic homeostasis shifts after callus formation and shoot regeneration in tomato

    Science.gov (United States)

    Kumari, Alka; Ray, Kamalika; Sadhna, Sadhna; Pandey, Arun Kumar; Sreelakshmi, Yellamaraju; Sharma, Rameshwar

    2017-01-01

    Plants can regenerate from a variety of tissues on culturing in appropriate media. However, the metabolic shifts involved in callus formation and shoot regeneration are largely unknown. The metabolic profiles of callus generated from tomato (Solanum lycopersicum) cotyledons and that of shoot regenerated from callus were compared with the pct1-2 mutant that exhibits enhanced polar auxin transport and the shr mutant that exhibits elevated nitric oxide levels. The transformation from cotyledon to callus involved a major shift in metabolite profiles with denser metabolic networks in the callus. In contrast, the transformation from callus to shoot involved minor changes in the networks. The metabolic networks in pct1-2 and shr mutants were distinct from wild type and were rewired with shifts in endogenous hormones and metabolite interactions. The callus formation was accompanied by a reduction in the levels of metabolites involved in cell wall lignification and cellular immunity. On the contrary, the levels of monoamines were upregulated in the callus and regenerated shoot. The callus formation and shoot regeneration were accompanied by an increase in salicylic acid in wild type and mutants. The transformation to the callus and also to the shoot downregulated LST8 and upregulated TOR transcript levels indicating a putative linkage between metabolic shift and TOR signalling pathway. The network analysis indicates that shift in metabolite profiles during callus formation and shoot regeneration is governed by a complex interaction between metabolites and endogenous hormones. PMID:28481937

  9. The Effect of Vermicompost on Reducing the Adverse Effects of Water Stress on Growth and Chemical Composition of Corn in a Calcareous Soil

    Directory of Open Access Journals (Sweden)

    leila zare

    2017-01-01

    equal to 0, 20, 40 and 60 Mg ha-1 and three moisture levels(100, 80and 60%of field capacity(FC. The soil samples were collected (0-30 cm depth from a calcareous soil (Fine, mixed, mesic, Typic, Calcixrepts, located at Bajgah, Shiraz, Iran. Soil samples were mixed thoroughly with different levels of vermicompost and transfred to plastic pots. Six corn seeds were planted in each pot and were thinned to three uniform plants, one week after germination. Eight weeks after germination, corn shoots were harvested, dried and recorded. Plant samples were grind using a portable grinder and transferred to the laboratory for chemical analysis. The collected data were statistically analysed using SAS software (9.1.3 package. Results and Discussion: The results indicated that with increasing the levels of vermicompost, dry matter yield and concentrations of total nitrogen (TN, phosphorus (P, iron (Fe, copper(Cu and zinc (Zn in corn shoots were significantly increased. But, due to the antagonistic relationship between manganese (Mn and Zn or Fe,concentrations of Mn were significantly decreased. However, the concentration of Mn was in the sufficiency range. The highest dry matter yield and concentrations of nitrogen and phosphorus in corn shoot was observed at 30 g kg-1 vermicompost treatment, with 19, 10 and 20 % increase (compared to the control, respectively. The application of 30 g kg-1 vermicompost increased the concentrations of Zn, Cu and Fe by 41%, 90% and 75%, respectively and concentration of Mn decreased by 11.88%, compared to the control. Increasing the levels of water stress increased significantly the concentration of nutrients in corn shoot due to the reduction of corn biomass. The highest increase in nutrient concentrations was observed at 60% FC moisture level. Nitrogen and phosphorus concentrations in corn shoots by 12.5and 22.5% and Zn, Cu, Fe and Mn by 25, 83, 43and29% were higher compared to those of control (100% FC, respectively. The interaction effects of water

  10. Germination, seedling growth and relative water content of shoot in ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-08-18

    Aug 18, 2008 ... (mg), root : shoot length (R:S) ratio, and relative water content of shoot (RWC, %) were investigated in this study. The results ... seedlings may provide an advantage by allowing access ... Residual chlorine was eliminated by.

  11. Conservation and multiplication of encapsulated micro shoots of Rauvolfia vomitoria--an endangered medicinal tree: ISSR and RAPD based evaluation of genetic fidelity of converted plantlets.

    Science.gov (United States)

    Mehrotra, Shakti; Rahman, Liaq Ur; Mishra, Jahnvi; Kukreja, Arun K

    2012-12-01

    The in vitro grown axillary micro shoots of Rauvolfia vomitoria were encapsulated in alginate beads. Following 6 months of normal storage at 25 +/- 2 degrees C the regrowth of encapsulated micro shoots, reached 95.2% within 40 days of incubation on MS medium containing 1.0 mg/L BAP and 0.1 mg/L NAA. Among the responding encapsulated explants 69.6% showed emergence of multiple shoots. The developing shoots showed rhizogenesis in two weeks following their transfer to rooting medium. Healthy plants were established in a glass house with 95% survival. Of the 50 RAPD primers tested, 10 produced 23 clear and reproducible amplicons, with an average of 2.3 bands per primer. Eleven ISSR primers produced a total of 42 bands, with a size range of 0.1-1.9 kb. The number of scorable bands for each primer varied from 2 to 6, with an average of 3.81. The similarity matrix, calculated individually from the results obtained from ISSR and RAPD analysis, showed similarity coefficients ranging from 1.0 for RAPD and 0.85 to 1.0 for ISSR.

  12. An Analysis of US School Shooting Data (1840-2015)

    Science.gov (United States)

    Paradice, David

    2017-01-01

    This paper describes the construction and descriptive analysis of a data set of United States school shooting events. Three hundred forty-three shooting events are included, spanning 175 years of United States educational history. All levels of US educational institution are included. Events are included when a firearm is discharged, regardless of…

  13. Revisiting the Virginia Tech Shootings: An Ecological Systems Analysis

    Science.gov (United States)

    Hong, Jun Sung; Cho, Hyunkag; Lee, Alvin Shiulain

    2010-01-01

    School shooting cases since the late 1990s have prompted school officials and legislators to develop and implement programs and measures that would prevent violence in school. Despite the number of explanations by the media, politicians, organizations, and researchers about the etiology of school shootings, we are not united in our understanding…

  14. The effect of time constraints and running phases on combined event pistol shooting performance.

    Science.gov (United States)

    Dadswell, Clare; Payton, Carl; Holmes, Paul; Burden, Adrian

    2016-01-01

    The combined event is a crucial aspect of the modern pentathlon competition, but little is known about how shooting performance changes through the event. This study aimed to identify (i) how performance-related variables changed within each shooting series and (ii) how performance-related variables changed between each shooting series. Seventeen modern pentathletes completed combined event trials. An optoelectronic shooting system recorded score and pistol movement, and force platforms recorded centre of pressure movement 1 s prior to every shot. Heart rate and blood lactate values were recorded throughout the event. Whilst heart rate and blood lactate significantly increased between series (P  0.05). Thus, combined event shooting performance following each running phase appears similar to shooting performance following only 20 m of running. This finding has potential implications for the way in which modern pentathletes train for combined event shooting, and highlights the need for modern pentathletes to establish new methods with which to enhance shooting accuracy.

  15. Efficient regeneration of sorghum, Sorghum bicolor (L.) Moench, from shoot-tip explant.

    Science.gov (United States)

    Syamala, D; Devi, Prathibha

    2003-12-01

    Novel protocols for production of multiple shoot-tip clumps and somatic embryos of Sorghum bicolor (L.) Moench were developed with long-term goal of crop improvement through genetic transformation. Multiple shoot-tip clumps were developed in vitro from shoot-tip explant of one-week old seedling, cultured on MS medium containing only BA (0.5, 1 or 2 mg/l) or both BA (1 or 2 mg/l) and 2,4-D (0.5 mg/l) with bi-weekly subculture. Somatic embryos were directly produced on the enlarged dome shaped growing structures that developed from the shoot-tips of one-week old seedling explants (without any callus formation) when cultured on MS medium supplemented with both 2,4-D (0.5 mg/l) and BA (0.5 mg/l). However, the supplementation of MS medium with only 2,4-D (0.5 mg/l) induced compact callus without any plantlet regeneration. Each multiple shoot-clump was capable of regenerating more than 80 shoots via an intensive differentiation of both axillary and adventitious shoot buds, the somatic embryos were capable of 90% germination, plant conversion and regeneration. The regenerated shoots could be efficiently rooted on MS medium containing indole-3-butyric acid (IBA 1 mg/l). The plants were successfully transplanted to glasshouse and grown to maturity with a survival rate of 98%. Morphogenetic response of the explants was found to be genotypically independent.

  16. Assessment of Sampling Error Associated with Collection and Analysis of Soil Samples at a Firing Range Contaminated with HMX

    National Research Council Canada - National Science Library

    Jenkins, Thomas F

    1997-01-01

    Short-range and mid-range (grid size) spatial heterogeneity in explosives concentrations within surface soils was studied at an active antitank firing range at the Canadian Force Base-Valcartier, Val-Belair, Quebec...

  17. GPU based numerical simulation of core shooting process

    Directory of Open Access Journals (Sweden)

    Yi-zhong Zhang

    2017-11-01

    Full Text Available Core shooting process is the most widely used technique to make sand cores and it plays an important role in the quality of sand cores. Although numerical simulation can hopefully optimize the core shooting process, research on numerical simulation of the core shooting process is very limited. Based on a two-fluid model (TFM and a kinetic-friction constitutive correlation, a program for 3D numerical simulation of the core shooting process has been developed and achieved good agreements with in-situ experiments. To match the needs of engineering applications, a graphics processing unit (GPU has also been used to improve the calculation efficiency. The parallel algorithm based on the Compute Unified Device Architecture (CUDA platform can significantly decrease computing time by multi-threaded GPU. In this work, the program accelerated by CUDA parallelization method was developed and the accuracy of the calculations was ensured by comparing with in-situ experimental results photographed by a high-speed camera. The design and optimization of the parallel algorithm were discussed. The simulation result of a sand core test-piece indicated the improvement of the calculation efficiency by GPU. The developed program has also been validated by in-situ experiments with a transparent core-box, a high-speed camera, and a pressure measuring system. The computing time of the parallel program was reduced by nearly 95% while the simulation result was still quite consistent with experimental data. The GPU parallelization method can successfully solve the problem of low computational efficiency of the 3D sand shooting simulation program, and thus the developed GPU program is appropriate for engineering applications.

  18. SEASONAL CHANGES IN ROOT AND SOIL RESPIRATION OF OZONE-EXPOSED PONDEROSA PINE (PINUS PONDEROSA) GROWN IN DIFFERENT SUBSTRATES

    Science.gov (United States)

    Exposure to(ozone 0-3)has been shown to decrease the allocation of carbon to tree roots. Decreased allocation of carbon to roots might disrupt root metabolism and rhizosphere organisms. The effects of soil type and shoot 0, exposure on below-ground respiration and soil microbial ...

  19. Micropropagation of Plantago asiatica L. through culture of shoot-tips

    Directory of Open Access Journals (Sweden)

    Joanna Makowczyńska

    2011-01-01

    Full Text Available Shoot-tip multiplication of the medicinal species - Plantago asiatica was carried on MS medium with IAA and BAP or kinetin. Best results in micropropagation were achieved by adding 0.1 mg/dm3 IAA and 1 mg/dm3 BAP. After 6 weeks shoots were transferred to MS medium for rooting. The resulting plantlets were transferred after 8 weeks into pots and after a period of adaptation into the ground (field culture. The species Plantago asiatica was propagated in vitro by shoot-tip multiplication for the first time.

  20. Lippia dulcis shoot cultures as a source of the sweet sesquiterpene hernandulcin.

    Science.gov (United States)

    Sauerwein, M; Flores, H E; Yamazaki, T; Shimomura, K

    1991-04-01

    The axenic shoot culture of Lippia dulcis Trev., Verbenaceae, was established on hormone-free Murashige-Skoog solid medium containing 3% sucrose. Shoots were cultured in various liquid or solid media. Woody Plant liquid medium was best for shoot multiplication, but the production of hernandulcin was relatively low. The highest hernandulcin content (2.9% dry wt) was obtained after 28 days of culture on Murashige-Skoog solid medium containing 2% sucrose. The addition of chitosan to the culture media enhanced the growth of shoots as well as the production of hernandulcin, especially with the liquid medium.

  1. Effects of Nanoscale Carbon Black Modified by HNO3 on Immobilization and Phytoavailability of Ni in Contaminated Soil

    Directory of Open Access Journals (Sweden)

    Jiemin Cheng

    2015-01-01

    Full Text Available A surface-modified nanoscale carbon black (MCB as Ni adsorbent in contaminated soil was prepared by oxidizing the carbon black with 65% HNO3. The surface properties of the adsorbent were characterized by zeta potential analysis, scanning electron microscopy (SEM, and Fourier transform infrared spectroscopy (FTIRs. Batch experiments were conducted to evaluate the improvement of Ni2+ adsorption by MCB. Greenhouse cultivation experiments were conducted to examine the effect of MCB on the DTPA-extractable Ni2+ in soil, Ni2+ uptake of ryegrass shoot, and growth of ryegrass. Results indicated that MCB had much lower negative zeta potential, more functional groups for exchange and complexation of cation, and more heterogeneous pores and cavities for the adsorption of cation than the unmodified parent one (CB. MCB showed enhanced sorption capacity for Ni (qmax, 49.02 mg·g−1 compared with CB (qmax, 39.22 mg·g−1. Greenhouse cultivation experiment results showed that the biomass of ryegrass shoot and the Ni uptake of the ryegrass shoot were significantly increased and the concentrations of DTPA-extractable Ni in soil were significantly decreased with the increasing of MCB amount. It is clear from this work that the MCB had good adsorption properties for the Ni and could be applied in the in situ immobilization and remediation of heavy metal contaminated saline-alkali soils.

  2. Results of field studies on 90SR and stable SR soil-to-plant transfer

    International Nuclear Information System (INIS)

    Gerzabek, M.H.; Artner, C.; Horak, O.; Mueck, K.

    1992-01-01

    In 1987 and 1988 at 35 sites plants ready to harvest and the corresponding soils (0 - 20 cm) were collected for 90 Sr and stable strontium analyses. Sample preparation and measurement led to a detection limit of 0.008 Bq 90 Sr kg -1 . The 90 Sr-contamination of Austrian soils ranged from 396 to 1998 Bq m -2 . Known from literature the contribution of the Chernobyl fallout amounted to app. 25 % of the total contamination. Stable strontium contents of the soils were between 6 and 62.5 mg kg -1 . Bariumtriethanolamine extracted 17.7 to 62.3 % of the total stable Sr in soil. 90 Sr-concentrations in cereal grains ranged from 0.03 to 0.67 Bq kg -1 (fresh wight) for maize and barley, respectively. The values for other foodstuff were between 0.15 (white cabbage) and 0.91 Bq kg -1 (spinach). Stable strontium contents were between 0.079 mg kg -1 (maize) and 72.5 mg kg -1 (celery shoot). The following mean 90 Sr soil-to-plant transfer factors for cereal grains were obtained: 0.010 (maize), 0.097 (rye), 0.049 (wheat), 0.095 (barley). Transfer factors for straw were up to 50 times higher (maize). The transfer of 90 Sr into vegetables and potatoes reached the same order of magnitude compared to the cereals. In all cases soil-to-plant transfer of stable Sr was clearly lower up to 60 % of the respective values for 90 Sr. Thus natural stable strontium is less plant available than 90 Sr. The influence of soil parameters on the 90 Sr transfer into plants was examinated by correlation analyses. Increasing exchangeable calcium contents of the soils resulted in a significant reduction of Sr soil-to-barley straw transfer. (authors)

  3. Enhanced root and shoot growth of wheat (Triticum aestivum L.) by Trichoderma harzianum from Turkey.

    Science.gov (United States)

    Kucuk, Cigdem

    2014-01-01

    It is well known that Trichoderma species can be used as biocontrol and plant growth promote agent. In this study, Trichoderma harzianum isolates were evaluated for their growth promotion effects on wheat in greenhouse experiments. Two isolates of T. harzianum were used. The experimental design was a randomized complete block with three replications. Seeds were inoculated with conidial suspensions of each isolate. Wheat plants grown in steriled soil in pots. T. harzianum T8 and T15 isolates increased wheat length, root dry weight and shoot dry weight according to untreated control. Turkish isolates T8 and T15 did not produce damage in seeds nor in plants.

  4. Least Limiting Water Range and Load Bearing Capacity of Soil under Types of Tractor-Trailers for Mechanical Harvesting of Green Sugarcane

    Directory of Open Access Journals (Sweden)

    Antonio Higino Frederico Pereira

    2015-12-01

    Full Text Available ABSTRACT The expansion of the sugarcane industry in Brazil has intensified the mechanization of agriculture and caused effects on the soil physical quality. The purpose of this study was to evaluate the limiting water range and soil bearing capacity of a Latossolo Vermelho distroférrico típico (Rhodic Hapludox under the influence of different tractor-trailers used in mechanical sugarcane harvesting. The experiment was arranged in a randomized block design with five replications. The treatments consisted of green sugarcane harvesting with: harvester without trailer (T1; harvester with two trailers with a capacity of 10 Mg each (T2; harvester with trailer with a capacity of 20 Mg (T3 and harvester and truck with trailer with a capacity of 20 Mg (10 Mg per compartment (T4. The least limiting water range and soil bearing capacity were evaluated. The transport equipment to remove the harvested sugarcane from the field (trailer at harvest decreased the least limiting water range, reducing the structural soil quality. The truck trailer caused the greatest impact on the soil physical properties studied. The soil load bearing capacity was unaffected by the treatments, since the pressure of the harvester (T1 exceeded the pre-consolidation pressure of the soil.

  5. How to talk (and not to talk) about school shootings

    OpenAIRE

    Scheper-Hughes, N

    2018-01-01

    © RAI 2018 In this guest editorial, the author addresses the latest school shootings at the Marjory Stoneman Douglas High School in Parkland, Florida. This event is weighed up against reports written by prominent academics, including anthropologists, during previous school shootings.

  6. School Shootings Stun Reservation

    Science.gov (United States)

    Borja, Rhea R.; Cavanagh, Sean

    2005-01-01

    This article deals with the impact brought by the school shootings at Red Lake Indian Reservation in Minnesota to the school community. A deeply troubled 16-year-old student shot and killed seven other people and himself at a high school. The nation's deadliest school attack since the 1999 slayings at Colorado's suburban Columbine High School took…

  7. Violent mass shootings in Sweden from 1960 to 1995: profiles, patterns, and motives.

    Science.gov (United States)

    Lindquist, O; Lidberg, L

    1998-03-01

    During the past few decades, violent mass shooting in Sweden has increased rapidly. In the 36 years between 1960 and 1995, fourteen such occasions were recorded, during which 32 people were killed and 57 were wounded. The 14 offenders were men between the ages of 17 and 61 years. In the 20 years from 1960 to 1979, five shootings were committed by five offenders, leaving 10 dead and 13 wounded; in the 16 years between 1980 and 1995, there were nine different shootings committed by nine offenders, with 22 dead and 44 wounded. Seven of the shootings were classified as mass shootings, six as spree shootings, and one as a serial shooting. In all but four of these cases, the firearms used were illegal weapons. The four legal firearms belonged to an unemployed young laborer, an officer, a former United Nations (U.N.) soldier, and a member of the Swedish military volunteer corps. Of those killed, 68.8% were strangers to the offender; among the wounded, the corresponding figure was 89.5%. Profiles of the offenders and of the victims were studied. The psychiatric diagnoses among the offenders and the measures taken to prevent the increase in mass shooting in Sweden are presented.

  8. Evaluation of Clonostachys rosea for Control of Plant-Parasitic Nematodes in Soil and in Roots of Carrot and Wheat.

    Science.gov (United States)

    Iqbal, Mudassir; Dubey, Mukesh; McEwan, Kerstin; Menzel, Uwe; Franko, Mikael Andersson; Viketoft, Maria; Jensen, Dan Funck; Karlsson, Magnus

    2018-01-01

    Biological control is a promising approach to reduce plant diseases caused by nematodes. We tested the effect of the fungus Clonostachys rosea strain IK726 inoculation on nematode community composition in a naturally nematode infested soil in a pot experiment, and the effect of C. rosea on plant health. The numbers of plant-parasitic nematode genera extracted from soil and plant roots decreased by 40 to 73% when C. rosea was applied, while genera of nonparasitic nematodes were not affected. Soil inoculation of C. rosea increased fresh shoot weight and shoot length of wheat plants by 20 and 24%, respectively, while only shoot dry weight increased by 48% in carrots. Light microscopy of in vitro C. rosea-nematode interactions did not reveal evidence of direct parasitism. However, culture filtrates of C. rosea growing in potato dextrose broth, malt extract broth and synthetic nutrient broth exhibited toxicity toward nematodes and immobilized 57, 62, and 100% of the nematodes, respectively, within 48 h. This study demonstrates that C. rosea can control plant-parasitic nematodes and thereby improve plant growth. The most likely mechanism responsible for the antagonism is antibiosis through production of nematicidal compounds, rather than direct parasitism.

  9. Effect of fertilizer amendments on phytoremediation of Cd-contaminated soil by a newly discovered hyperaccumulator Solanum nigrum L

    Energy Technology Data Exchange (ETDEWEB)

    Wei Shuhe, E-mail: shuhewei@yahoo.com.cn [Key Laboratory of Terrestrial Ecological Process, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016 (China); Li Yunmeng [Key Laboratory of Terrestrial Ecological Process, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016 (China); Graduate School of Chinese Academy of Sciences, Beijing 100039 (China); Zhou Qixing, E-mail: zhouqx523@yahoo.com.cn [Key Laboratory of Terrestrial Ecological Process, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016 (China); Srivastava, Mrittunjai [North Florida Research and Education Center, University of Florida, Quincy, FL 32351-5677 (United States); Chiu Siuwai [Department of Biology, The Chinese University of Hong Kong, Shatin, N.T. (Hong Kong); Zhan Jie [Department of Biotechnology, Liaoning University of Traditional Chinese Medicine, Shenyang 110101 (China); Wu Zhijie; Sun Tieheng [Key Laboratory of Terrestrial Ecological Process, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016 (China)

    2010-04-15

    Phytoremediation is a cost-effective, simple and sustainable beneficiary technique to purify the polluted environment. Solanum nigrum L., a newly found cadmium (Cd) hyperaccumulator, has shown the potential to remediate Cd-contaminated soils. Present study investigated the effects of fertilizer amendments on the Cd uptake by S. nigrum. Chicken manure and urea are usual agricultural fertilizers and more environmental friendly. The results showed that Cd concentrations in shoots of S. nigrum were significantly decreased (p < 0.05) by 28.2-34.6%, as compared to that of without the addition of chicken manure, but not the case for urea treatment. However, Cd extraction capacities ({mu}g pot{sup -1}) in shoot biomass of S. nigrum were significantly increased (p < 0.05) due to increased shoot biomass. In addition, available Cd concentration in soil significantly decreased due to addition of chicken manure. Thus, urea might be a better fertilizer for strengthening phytoextraction rate of S. nigrum to Cd, and chicken manure may be a better fertilizer for phytostabilization.

  10. Improvement of cadmium phytoremediation after soil inoculation with a cadmium-resistant Micrococcus sp.

    Science.gov (United States)

    Sangthong, Chirawee; Setkit, Kunchaya; Prapagdee, Benjaphorn

    2016-01-01

    Cadmium-resistant Micrococcus sp. TISTR2221, a plant growth-promoting bacterium, has stimulatory effects on the root lengths of Zea mays L. seedlings under toxic cadmium conditions compared to uninoculated seedlings. The performance of Micrococcus sp. TISTR2221 on promoting growth and cadmium accumulation in Z. mays L. was investigated in a pot experiment. The results indicated that Micrococcus sp. TISTR2221significantly promoted the root length, shoot length, and dry biomass of Z. mays L. transplanted in both uncontaminated and cadmium-contaminated soils. Micrococcus sp. TISTR2221 significantly increased cadmium accumulation in the roots and shoots of Z. mays L. compared to uninoculated plants. At the beginning of the planting period, cadmium accumulated mainly in the shoots. With a prolonged duration of cultivation, cadmium content increased in the roots. As expected, little cadmium was found in maize grains. Soil cadmium was significantly reduced with time, and the highest percentage of cadmium removal was found in the bacterial-inoculated Z. mays L. after transplantation for 6 weeks. We conclude that Micrococcus sp. TISTR2221 is a potent bioaugmenting agent, facilitating cadmium phytoextraction in Z. mays L.

  11. Tree species and soil nutrient profiles in old-growth forests of the Oregon Coast Range

    Science.gov (United States)

    Cross, Alison; Perakis, Steven S.

    2011-01-01

    Old-growth forests of the Pacific Northwest provide a unique opportunity to examine tree species – soil relationships in ecosystems that have developed without significant human disturbance. We characterized foliage, forest floor, and mineral soil nutrients associated with four canopy tree species (Douglas-fir (Pseudotsuga menziesii (Mirbel) Franco), western hemlock (Tsuga heterophylla (Raf.) Sarg.), western redcedar (Thuja plicata Donn ex D. Don), and bigleaf maple (Acer macrophyllum Pursh)) in eight old-growth forests of the Oregon Coast Range. The greatest forest floor accumulations of C, N, P, Ca, Mg, and K occurred under Douglas-fir, primarily due to greater forest floor mass. In mineral soil, western hemlock exhibited significantly lower Ca concentration and sum of cations (Ca + Mg + K) than bigleaf maple, with intermediate values for Douglas-fir and western redcedar. Bigleaf maple explained most species-based differences in foliar nutrients, displaying high concentrations of N, P, Ca, Mg, and K. Foliar P and N:P variations largely reflected soil P variation across sites. The four tree species that we examined exhibited a number of individualistic effects on soil nutrient levels that contribute to biogeochemical heterogeneity in these ecosystems. Where fire suppression and long-term succession favor dominance by highly shade-tolerant western hemlock, our results suggest a potential for declines in both soil Ca availability and soil biogeochemical heterogeneity in old-growth forests.

  12. Direct shoot organogenesis of Digitalis trojana Ivan., an endemic ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-03-15

    Mar 15, 2010 ... An efficient protocol for in vitro propagation of Digitalis trojana Ivan. was developed via adventitious shoot regeneration. Leaf explants were cultured on MS which were supplemented with different concentrations of NAA (0.1, 0.5, 1.0 mg/ml) and BAP (0.1, 0.5, 1.0, 3.0, 5.0 mg/ml) for shoot formation.

  13. Translocation of sorbitol and other photosynthates in golden delicious apple shoots

    International Nuclear Information System (INIS)

    Steenkamp, J.; Terblanche, J.H.; De Villiers, O.T.

    1982-01-01

    This study was undertaken to determine to what extent sorbitol and other photosynthates are translocated in Golden Delicious apple shoots. The distribution of radioactivity in the different fractions, after the leaves had been exposed to radiocarbon, was found in segment of the shoots directly below the treatment leaves. The highest 14 C activity was in the carbohydrate fraction. The results indicate that sorbitol is the principal carbohydrate transported in Golden Delicious apple shoots

  14. The effects of organic matter-mineral interactions and organic matter chemistry on diuron sorption across a diverse range of soils.

    Science.gov (United States)

    Smernik, Ronald J; Kookana, Rai S

    2015-01-01

    Sorption of non-ionic organic compounds to soil is usually expressed as the carbon-normalized partition coefficient (KOC), because it is assumed that the main factor that influences the amount sorbed is the organic carbon content of the soil. However, KOC can vary by a factor of at least ten across a range of soils. We investigated two potential causes of variation in diuron KOC - organic matter-mineral interactions and organic matter chemistry - for a diverse set of 34 soils from Sri Lanka, representing a wide range of soil types. Treatment with hydrofluoric acid (HF-treatment) was used to concentrate soil organic matter. HF-treatment increased KOC for the majority of soils (average factor 2.4). We attribute this increase to the blocking of organic matter sorption sites in the whole soils by minerals. There was no significant correlation between KOC for the whole soils and KOC for the HF-treated soils, indicating that the importance of organic matter-mineral interactions varied greatly amongst these soils. There was as much variation in KOC across the HF-treated soils as there was across the whole soils, indicating that the nature of soil organic matter is also an important contributor to KOC variability. Organic matter chemistry, determined by solid-state (13)C nuclear magnetic resonance (NMR) spectroscopy, was correlated with KOC for the HF-treated soils. In particular, KOC increased with the aromatic C content (R=0.64, p=1×10(-6)), and decreased with O-alkyl C (R=-0.32, p=0.03) and alkyl C (R=-0.41, p=0.004) content. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Influence of calcium content of tissue on hyperhydricity and shoot-tip necrosis of in vitro regenerated shoots of Lavandula angustifolia Mill.

    Directory of Open Access Journals (Sweden)

    Marília Pereira Machado

    2014-10-01

    Full Text Available In the present study, the effects of two CaCl2.2H2O levels (440 and 1320 mg L-1 and two subcultures were evaluated on in vitro shoots of Lavandula angustifolia cv. Provence Blue. Ca2+ content of the apical, middle and basal portion of shoots was determined. Increasing CaCl2.2H2O level in the culture medium increased tissue Ca2+ content and decreased hyperhydricity. Shoot-tip necrosis also decreased with 1320 mg L-1 CaCl2.2H2O, but it did not occur in the second subculture. The middle and basal portion had higher Ca2+ content than apical portion. In non-hyperhydric tissues, there were smaller and more juxtaposed cells. Scanning electron microscopy of the leaves demonstrated that trichomes from in vitro leaf surface occurred in smaller quantities.

  16. Microspatial ecotone dynamics at a shifting range limit: plant-soil variation across salt marsh-mangrove interfaces.

    Science.gov (United States)

    Yando, E S; Osland, M J; Hester, M W

    2018-05-01

    Ecotone dynamics and shifting range limits can be used to advance our understanding of the ecological implications of future range expansions in response to climate change. In the northern Gulf of Mexico, the salt marsh-mangrove ecotone is an area where range limits and ecotone dynamics can be studied in tandem as recent decreases in winter temperature extremes have allowed for mangrove expansion at the expense of salt marsh. In this study, we assessed aboveground and belowground plant-soil dynamics across the salt marsh-mangrove ecotone quantifying micro-spatial patterns in horizontal extent. Specifically, we studied vegetation and rooting dynamics of large and small trees, the impact of salt marshes (e.g. species and structure) on mangroves, and the influence of vegetation on soil properties along transects from underneath the mangrove canopy into the surrounding salt marsh. Vegetation and rooting dynamics differed in horizontal reach, and there was a positive relationship between mangrove tree height and rooting extent. We found that the horizontal expansion of mangrove roots into salt marsh extended up to eight meters beyond the aboveground boundary. Variation in vegetation structure and local hydrology appear to control mangrove seedling dynamics. Finally, soil carbon density and organic matter did not differ within locations across the salt marsh-mangrove interface. By studying aboveground and belowground variation across the ecotone, we can better predict the ecological effects of continued range expansion in response to climate change.

  17. Microspatial ecotone dynamics at a shifting range limit: plant–soil variation across salt marsh–mangrove interfaces

    Science.gov (United States)

    Yando, Erik S.; Osland, Michael J.; Hester, Mark H.

    2018-01-01

    Ecotone dynamics and shifting range limits can be used to advance our understanding of the ecological implications of future range expansions in response to climate change. In the northern Gulf of Mexico, the salt marsh–mangrove ecotone is an area where range limits and ecotone dynamics can be studied in tandem as recent decreases in winter temperature extremes have allowed for mangrove expansion at the expense of salt marsh. In this study, we assessed aboveground and belowground plant–soil dynamics across the salt marsh–mangrove ecotone quantifying micro-spatial patterns in horizontal extent. Specifically, we studied vegetation and rooting dynamics of large and small trees, the impact of salt marshes (e.g. species and structure) on mangroves, and the influence of vegetation on soil properties along transects from underneath the mangrove canopy into the surrounding salt marsh. Vegetation and rooting dynamics differed in horizontal reach, and there was a positive relationship between mangrove tree height and rooting extent. We found that the horizontal expansion of mangrove roots into salt marsh extended up to eight meters beyond the aboveground boundary. Variation in vegetation structure and local hydrology appear to control mangrove seedling dynamics. Finally, soil carbon density and organic matter did not differ within locations across the salt marsh-mangrove interface. By studying aboveground and belowground variation across the ecotone, we can better predict the ecological effects of continued range expansion in response to climate change.

  18. Screening variability and change of soil moisture under wide-ranging climate conditions: Snow dynamics effects.

    Science.gov (United States)

    Verrot, Lucile; Destouni, Georgia

    2015-01-01

    Soil moisture influences and is influenced by water, climate, and ecosystem conditions, affecting associated ecosystem services in the landscape. This paper couples snow storage-melting dynamics with an analytical modeling approach to screening basin-scale, long-term soil moisture variability and change in a changing climate. This coupling enables assessment of both spatial differences and temporal changes across a wide range of hydro-climatic conditions. Model application is exemplified for two major Swedish hydrological basins, Norrström and Piteälven. These are located along a steep temperature gradient and have experienced different hydro-climatic changes over the time period of study, 1950-2009. Spatially, average intra-annual variability of soil moisture differs considerably between the basins due to their temperature-related differences in snow dynamics. With regard to temporal change, the long-term average state and intra-annual variability of soil moisture have not changed much, while inter-annual variability has changed considerably in response to hydro-climatic changes experienced so far in each basin.

  19. Editor’s note

    Science.gov (United States)

    Schmitt, Christopher J.

    2017-01-01

    Heavy metal contamination at shooting ranges is well documented (e.g., Heier et al. 2009; Islam et al. 2016). Primarily lead, but also copper, zinc, and antimony often occur at high concentrations in shooting range soils; cadmium, nickel, silver, and arsenic may also be present (Cao et al. 2003; Islam et al. 2016). These metals represent a potential threat to human health and wildlife. Although much of the lead and other metals remains in the soil (Clausen et al. 2011), some metals can also contaminate groundwater and surface water and thereby threaten aquatic life (Heier et al. 2009). Results of a study published in the current issue of the Bulletin of Environmental Contamination and Toxicology (Stauffer et al. 2017) indicate that mercury contamination may also be an issue at shooting ranges, which has not been previously reported.

  20. The effect of distance on moral engagement: Event related potentials and alpha power are sensitive to perspective in a virtual shooting task

    Directory of Open Access Journals (Sweden)

    Kirsten ePetras

    2016-01-01

    Full Text Available In a shooting video game we investigated whether increased distance reduces moral conflict. We measured and analysed the event related potential (ERP, including the N2 component, which has previously been linked to cognitive conflict from competing decision tendencies. In a modified go/nogo task designed to trigger moral conflict participants had to shoot suddenly appearing human like avatars in a virtual reality scene. The scene was seen either from an ego perspective with targets appearing directly in front of the participant or from a bird’s view, where targets were seen from above and more distant. To control for low level visual features, we conducted a visually identical control experiment, where the instruction to shoot was replaced by an instruction to detect. ERP waveforms showed differences between the two tasks as early as in the N1 time-range, with higher N1 amplitudes for the close perspective in the shoot task. Additionally, we found that pre-stimulus alpha power was significantly decreased in the ego, compared to the bird's view only for the shoot but not for the detect task. In the N2 time window, we observed main amplitude effects for response (nogo > go and distance (ego > bird perspective but no interaction with task type (shoot vs detect. We argue that the pre-stimulus and N1 effects can be explained by reduced attention and arousal in the distance condition when people are instructed to shoot. The lack of interaction in the N2 across tasks suggests that at that time point, the moral conflict is already resolved and response execution dominates. We discuss potential implications for real life shooting situations, especially considering recent developments in drone shootings which are per definition of a distant view.

  1. The Effect of Distance on Moral Engagement: Event Related Potentials and Alpha Power are Sensitive to Perspective in a Virtual Shooting Task.

    Science.gov (United States)

    Petras, Kirsten; Ten Oever, Sanne; Jansma, Bernadette M

    2015-01-01

    In a shooting video game we investigated whether increased distance reduces moral conflict. We measured and analyzed the event related potential (ERP), including the N2 component, which has previously been linked to cognitive conflict from competing decision tendencies. In a modified Go/No-go task designed to trigger moral conflict participants had to shoot suddenly appearing human like avatars in a virtual reality scene. The scene was seen either from an ego perspective with targets appearing directly in front of the participant or from a bird's view, where targets were seen from above and more distant. To control for low level visual features, we added a visually identical control condition, where the instruction to "shoot" was replaced by an instruction to "detect." ERP waveforms showed differences between the two tasks as early as in the N1 time-range, with higher N1 amplitudes for the close perspective in the "shoot" task. Additionally, we found that pre-stimulus alpha power was significantly decreased in the ego, compared to the bird's view only for the "shoot" but not for the "detect" task. In the N2 time window, we observed main amplitude effects for response (No-go > Go) and distance (ego > bird perspective) but no interaction with task type (shoot vs. detect). We argue that the pre-stimulus and N1 effects can be explained by reduced attention and arousal in the distance condition when people are instructed to "shoot." These results indicate a reduced moral engagement for increased distance. The lack of interaction in the N2 across tasks suggests that at that time point response execution dominates. We discuss potential implications for real life shooting situations, especially considering recent developments in drone shootings which are per definition of a distant view.

  2. Growth of wheat and lettuce and enzyme activities of soils under garlic stalk decomposition for different durations.

    Science.gov (United States)

    Han, Xu; Cheng, Zhihui; Meng, Huanwen

    2017-07-01

    Garlic (Allium sativum L.) stalk is a byproduct of garlic production that is normally thought of as waste but is now considered a useful biological resource. It is necessary to utilize this resource efficiently and reasonably to reduce environmental pollution and achieve sustainable agricultural development. The effect of garlic stalk decomposed for different durations was investigated in this study using wheat (Triticum aestivum L.) and lettuce (Lactuca sativa var. crispa L.) as test plants. Garlic stalk in early stages of decomposition inhibited the shoot and root lengths of wheat and lettuce, but it promoted the shoot and root lengths in later stages; longer durations of garlic stalk decomposition significantly increased the shoot and root fresh weights of wheat and lettuce, whereas shorter decomposing durations significantly decreased the shoot and root fresh weights; and garlic stalk at different decomposition durations increased the activities of urease, sucrase and alkaline phosphatase in soil where wheat or lettuce was planted. Garlic stalk decomposed for 30 or 40 days could promote the growth of wheat and lettuce plants as well as soil enzyme activities. These results may provide a scientific basis for the study and application of garlic stalk. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  3. The Sandy Hook Elementary School shooting as tipping point

    Science.gov (United States)

    Shultz, James M; Muschert, Glenn W; Dingwall, Alison; Cohen, Alyssa M

    2013-01-01

    Among rampage shooting massacres, the Sandy Hook Elementary School shooting on December 14, 2012 galvanized public attention. In this Commentary we examine the features of this episode of gun violence that has sparked strong reactions and energized discourse that may ultimately lead toward constructive solutions to diminish high rates of firearm deaths and injuries in the United States. PMID:28228989

  4. Accumulation of lead (Pb) in brown trout (Salmo trutta) from a lake downstream a former shooting range.

    Science.gov (United States)

    Mariussen, Espen; Heier, Lene Sørlie; Teien, Hans Christian; Pettersen, Marit Nandrup; Holth, Tor Fredrik; Salbu, Brit; Rosseland, Bjørn Olav

    2017-01-01

    An environmental survey was performed in Lake Kyrtjønn, a small lake within an abandoned shooting range in the south of Norway. In Lake Kyrtjønn the total water concentrations of Pb (14µg/L), Cu (6.1µg/L) and Sb (1.3µg/L) were elevated compared to the nearby reference Lake Stitjønn, where the total concentrations of Pb, Cu and Sb were 0.76, 1.8 and 0.12µg/L, respectively. Brown trout (Salmo trutta) from Lake Kyrtjønn had very high levels of Pb in bone (104mg/kg w.w.), kidney (161mg/kg w.w.) and the gills (137mg/kg d.w), and a strong inhibition of the ALA-D enzyme activity were observed in the blood (24% of control). Dry fertilized brown trout eggs were placed in the small outlet streams from Lake Kyrtjønn and the reference lake for 6 months, and the concentrations of Pb and Cu in eggs from the Lake Kyrtjønn stream were significantly higher than in eggs from the reference. More than 90% of Pb accumulated in the egg shell, whereas more than 80% of the Cu and Zn accumulated in the egg interior. Pb in the lake sediments was elevated in the upper 2-5cm layer (410-2700mg/kg d.w), and was predominantly associated with redox sensitive fractions (e.g., organic materials, hydroxides) indicating low potential mobility and bioavailability of the deposited Pb. Only minor amounts of Cu and Sb were deposited in the sediments. The present work showed that the adult brown trout, as well as fertilized eggs and alevins, may be subjected to increased stress due to chronic exposure to Pb, whereas exposure to Cu, Zn and Sb were of less importance. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Influence of mycorrhizal fungi on fate of E. coli O157:H7 and Salmonella in soil and internalization into Romaine lettuce plants.

    Science.gov (United States)

    Nicholson, April M; Gurtler, Joshua B; Bailey, Rebecca B; Niemira, Brendan A; Douds, David D

    2015-01-02

    The objectives of this study were to determine the influence of a symbiotic arbuscular mycorrhizal (AM) fungus on persistence of Salmonella and enterohemorrhagic Escherichia coli O157:H7 (EHEC) within soil, and survival within Romaine lettuce. Romaine seedlings were grown with or without AM fungi. Soil surrounding plants was inoculated with ca. 8 log CFU/plant of either Salmonella enterica or E. coli EHEC composites. Samples (soil, root, and shoot) were analyzed on days 1, 8, 15 and 22 for Salmonella and EHEC by direct plating and selective enrichment. Twenty-four hours after inoculation, populations of Salmonella and EHEC, respectively, were 4.20 and 3.24 log CFU/root, 2.52 and 1.17 log CFU/shoot, and 5.46 and 5.17 log CFU/g soil. By selective enrichment, samples tested positive for Salmonella or EHEC at day 22 at rates of 94 and 68% (shoot), 97 and 56% (root), and 100 and 75% (soil), respectively, suggesting that Salmonella has a greater propensity for survival than EHEC. Salmonella populations in soil remained as high as 4.35 log CFU/g by day 22, while EHEC populations dropped to 1.12 log CFU/g in the same amount of time. Ninety-two percent of all Romaine leaves in our study were positive for internalized Salmonella from days 8 to 22 and remained as high as 1.26 log CFU/shoot on day 22 in AM fungi+Romaine plants. There were no differences (P>0.05) between the survival of either pathogen based on the presence or absence of mycorrhizal fungi. Results of this study suggest that AM fungi do not affect the internalization and/or survival of either S. enterica or E. coli O157:H7 in Romaine lettuce seedlings. Our results should provide Romaine lettuce farmers confidence that the presence and/or application of AM fungi to crop soil is not a contributing factor to the internalization and survival of Salmonella or E. coli O157:H7 within Romaine lettuce plants. Published by Elsevier B.V.

  6. Genotypic Diversity for Biomass Accumulation and Shoot-Root Allometry in the Grass Brachypodium distachyon

    Science.gov (United States)

    Jansson, C.; Handakumbura, P. P.; Fortin, D.; Stanfill, B.; Rivas-Ubach, A.

    2017-12-01

    Predicting carbon uptake, assimilation and allocation for current and future biogeographical environments, including climate, is critical for our ability to select and/or design plant genotypes to meet increasing demand for plant biomass going into food, feed and energy production, while at the same time maintain or increase soil organic matter (SOM for soil fertility and carbon storage, and reduce emission of greenhouse gasses. As has been demonstrated for several plant species allometric relationships may differ between plant genotypes. Exploring plant genotypic diversity for biomass accumulation and allometry will potentially enable selection of genotypes with high CO2 assimilation and favorable allocation of recent photosynthate into above-ground and below-ground biomass. We are investigating genotypic diversity for PFTs in natural accessions of the annual C3 grass Brachypodium distachyon under current and future climate scenarios and how genotypic diversity correlates with metabolite profiles in aboveground and below-ground biomass. In the current study, we compare effects from non-stressed and drought conditions on biomass accumulation and shoot-root allometry.

  7. Effect of Piriformospora indica inoculation on root development and distribution of maize (Zea mays L.) in the presence of petroleum contaminated soil

    Science.gov (United States)

    Zamani, Javad; Hajabbasi, Mohammad Ali; Alaie, Ebrahim

    2014-05-01

    The root systems of most terrestrial plants are confronted to various abiotic and biotic stresses. One of these abiotic stresses is contamination of soil with petroleum hydrocarbon, which the efficiency of phytoremediation of petroleum hydrocarbons in soils is dependent on the ability of plant roots to development into the contaminated soils. Piriformospora indica represents a recently discovered fungus that transfers considerable beneficial impact to its host plants. A rhizotron experiment was conducted to study the effects of P. Indica inoculation on root distribution and root and shoot development of maize (Zea mays L.) in the presence of three patterns of petroleum contamination in the soil (subsurface contamination, continuous contamination and without contamination (control)). Root distribution and root and shoot development were monitored over time. The final root and shoot biomass and the final TPH concentration in the rhizosphere were determined. Analysis of digitized images which were prepared of the tracing of the appeared roots along the front rhizotrons showed the depth and total length of root network in the contamination treatments were significantly decreased. Although the degradation of TPH in the rhizosphere of maize was significant, but there were no significant differences between degradation of TPH in the rhizosphere of +P. indica plants in comparison to -P. indica plants.

  8. Assessment of carbon sources on in vitro shoot regeneration in tomato

    International Nuclear Information System (INIS)

    Shah, S.H.; Jan, S.A.

    2014-01-01

    An innovative approach for in vitro shoot regeneration by both direct and indirect means was developed in three tomato genotypes culturing hypocotyls and leaf discs explants on MS and N6 basal media fortified with various concentrations of carbon sources (sucrose and sorbitol) individually, accumulatively and also in amalgamation with various plant growth regulators. No response of in vitro shoot regeneration was recorded in all the genotypes by the individual application of carbon sources in both MS and N6 basal media. On the other hand, their accumulative effect rapidly enhanced the in vitro shoot regeneration frequency in all the genotypes. The highest shoot organogenesis frequency (100, 99.00 and 97.69%) was recorded in Rio Grande, Roma and Moneymaker, respectively on MS medium fortified with carbon sources (30: 30 g/l) culturing hypocotyls. Supplementation of sucrose: sorbitol (30: 30 g/l) in N6 medium along with different PGRs (0.1 mg/l IAA, 1.0 mg/l ZEA and 2.0 mg/l BAP) produced the highest shoot regeneration frequency (96.33, 92.69 and 88.74%) in Roma, Rio Grande and Moneymaker culturing leaf discs. Our findings suggest an alternative approach as hormone-free protocol for in vitro shoot regeneration in tomato that would save the resources with regard to hormonal costs and time. (author)

  9. Gene expression in arabidopsis shoot tips after liquid nitrogen exposure

    Science.gov (United States)

    Arabidopsis thaliana shoot tips can be successfully cryopreserved using either Plant Vitrification Solution 2 (PVS2) or Plant Vitrification Solution 3 (PVS3) as the cryoprotectant. We used this model system to identify suites of genes that were either upregulated or downregulated as shoot tips recov...

  10. Cryopreservation of in vitro -grown shoot tips of apricot ( Prunus ...

    African Journals Online (AJOL)

    In vitro grown apricot (Prunus armeniaca L.) cv. El-Hamawey shoot tips were successfully cryopreserved using an encapsulation-dehydration procedure. Shoot tips were encapsulated in calcium-alginate beads before preculture on woody plant (WP) medium supplemented with different sucrose concentrations; 0.1, 0.3, 0.5, ...

  11. Data management implementation plan for the removal action at the former YS-860 Firing Ranges, Oak Ridge Y-12 Plant, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    1998-03-01

    The former YS-860 Firing Ranges are located outside the primary facility fenceline at the Y-12 Plant within the Upper East Fork Poplar Creek watershed. The lead-contaminated soils at this site will be removed as part of early source actions of the Oak Ridge Reservation Environmental Restoration Program. The removal action will focus on the excavation of bullets and lead-contaminated soil from the shooting range berms, transportation of the material to a certified treatment and/or disposal facility, demolition and landfilling of a concrete trench and asphalt pathways, and grading and revegetating of the entire site. The primary purpose of environmental data management is to provide a system for generating and maintaining technically defensible data. To meet current regulatory requirements for the Environmental Restoration Program, complete documentation of the information flow must be established. This necessitates that each step in the data management process (collection, management, storage, and analysis) be adequately planned and documented. This document will serve to identify data management procedures, expected data types and flow, and roles and responsibilities for all data management activities associated with the YS-860 Firing Ranges removal action

  12. Bamboo shoot preservation for enhancing its business potential and local economy: a review.

    Science.gov (United States)

    Bal, Lalit M; Singhal, Poonam; Satya, Santosh; Naik, S N; Kar, Abhijit

    2012-01-01

    Bamboo shoot as food has been used in traditional ways by the tribal community the world over. For enhancing its business potential, research on various aspects of bamboo shoot as food is being carried out in Japan, Taiwan, Thailand, and Asian countries and several products are available in the market. Bamboo shoots are used as a delicacy in human food, are a good source of dietary fiber, low in fat and calories. The research studies included in this review paper focus on post-harvest preservation of bamboo shoot. In view of the seasonal availability of bamboo shoot, the post-harvest preservation system for handling cynogenic toxicity in raw shoot while keeping nutrients intact and enhancement of shelf life of the value added products assume great significance for the business potential of this natural product. A yardstick of assessing the "Shelf life-Quality Matrix" developed in this review paper would give a new perspective of quality control in case of preservation of bamboo shoot. Also, knowledge gaps identified in this paper would give impetus to new academic and R&D activities, in turn generating an innovative job profile in the food industry as well as rural entrepreneurship.

  13. Phytoremediation of Lead and Cadmium Contaminated Soils using Sunflower Plant

    OpenAIRE

    Nasser Sewalem; Soad Elfeky; Fatma El- Shintinawy

    2014-01-01

    Phytremediation has emerged as a practical approach to clean up metal-polluted soils. In this study the role of sunflower ( Helianthus annuus L.) plants as a potential phytoremediator to soils contaminated with cadmium (Cd) and lead (Pb) was investigated. Our results showed that the effect of Cd was stronger on the growth of the roots, while the effect of Pb was stronger on the shoots of sunflower seedlings. At the physiological level, Cd treatment was found to induce low levels of lipid pero...

  14. Application of soybean shoot-cutting in SMV-resistance genetic analysis

    Institute of Scientific and Technical Information of China (English)

    Haifeng Chen; Zhihui Shan; Xin'an zhou; Zhonglu Yang; Qiao Wan; Yanyan Yang; Shuilian Chen; Chanjuan Zhang; Limiao Chen; Songli Yuan; Dezhen Qiu

    2016-01-01

    Soybean mosaic virus (SMV) is one of the most serious diseases affecting soy-bean yield. Recombination inbred lines (RILs) are common materials for resistance genetic research. However, the population construction always takes quite a long time which pro-long the breading process. Shoot-cutting is a well-established technique for plant multipli-cation. It has high successful ratio in soybean. In this study, we use shoot-cutting to multiply two F2 populations from the crosses of susceptible and resistant varieties. Soybean plants can be multiplied from 1 into 3 homogenous ones within 30 days, bringing on well-grown plants with normal seeds. The SMV resistance from cutting-shoot plants was consistent with that from original plants. When shoot-cutting is applied in a F2 population, the pheno-typic and genotypic data can be simultaneously collected and corresponding saved during population development. The genetic research and resistant breeding can be effectively promoted by this technology.

  15. Phyto-toxicity and Phyto-remediation Potential of Mercury in Indian Mustard and Two Ferns with Mercury Contaminated Water and Oak Ridge Soil

    International Nuclear Information System (INIS)

    Su, Y.; Han, F.X.; Chen, J.; Shiyab, S.; Monts, D.L.; Monts, D.L.

    2009-01-01

    Phyto-remediation is an emerging technology that uses various plants to degrade, extract, contain, or immobilize contaminants from soil and water. Certain fern and Indian mustard species have been suggested as candidates for phyto-remediation of heavy metal-contaminated soil and water because of their high efficiency of accumulating metals in shoots and their high biomass production. Currently, no known hyper-accumulator plants for mercury have been found. Here we report the Hg uptake and phyto-toxicity by two varieties of fern and Indian mustard. Their potential for Hg phyto-remediation application was also investigated. Anatomical, histochemical and biochemical approaches were used to study mercury phyto-toxicity as well as anti-oxidative responses in ferns [Chinese brake fern (P. vittata) and Boston fern (N. exaltata)] and Indian mustard (Florida broadleaf and longstanding) (Brassica juncea L.) grown in a hydroponic system. Phyto-remediation potentials of these plant species were estimated based on their Hg uptake performance with contaminated soils from Oak Ridge (TN, USA). Our results show that mercury exposure led to severe phyto-toxicity accompanied by lipid peroxidation and rapid accumulation of hydrogen peroxide (H 2 O 2 ) in P. vittata, but not in N. exaltata. The two cultivars of fern responded differently to mercury exposure in terms of anti-oxidative enzymes (superoxide dismutase, SOD; catalase, CAT; peroxidase, POD; glutathione reductase, GR). Mercury exposure resulted in the accumulation of ascorbic acid (ASA) and glutathione (GSH) in the shoots of both cultivars of fern. On the other hand, Indian mustard effectively generated an enzymatic antioxidant defense system (especially CAT) to scavenge H 2 O 2 , resulting in lower H 2 O 2 in shoots with higher mercury concentrations. These two cultivars of Indian mustard demonstrated an efficient metabolic defense and adaptation system to mercury-induced oxidative stress. In both varieties of fern and Indian

  16. Novice Shooters With Lower Pre-shooting Alpha Power Have Better Performance During Competition in a Virtual Reality Scenario

    Directory of Open Access Journals (Sweden)

    Michael Pereira

    2018-04-01

    Full Text Available Competition changes the environment for athletes. The difficulty of training for such stressful events can lead to the well-known effect of “choking” under pressure, which prevents athletes from performing at their best level. To study the effect of competition on the human brain, we recorded pilot electroencephalography (EEG data while novice shooters were immersed in a realistic virtual environment representing a shooting range. We found a differential between-subject effect of competition on mu (8–12 Hz oscillatory activity during aiming; compared to training, the more the subject was able to desynchronize his mu rhythm during competition, the better was his shooting performance. Because this differential effect could not be explained by differences in simple measures of the kinematics and muscular activity, nor by the effect of competition or shooting performance per se, we interpret our results as evidence that mu desynchronization has a positive effect on performance during competition.

  17. beta-Blockade used in precision sports: effect on pistol shooting performance.

    Science.gov (United States)

    Kruse, P; Ladefoged, J; Nielsen, U; Paulev, P E; Sørensen, J P

    1986-08-01

    In a double-blind cross-over study of 33 marksmen (standard pistol, 25 m) the adrenergic beta 1-receptor blocker, metoprolol, was compared to placebo. Metoprolol obviously improved the pistol shooting performance compared with placebo. Shooting improved by 13.4% of possible improvement (i.e., 600 points minus actual points obtained) as an average (SE = 4%, 2P less than 0.002). The most skilled athletes demonstrated the clearest metoprolol improvement. We found no correlation between the shooting improvement and changes in the cardiovascular variables (i.e., changes of heart rate and systolic blood pressure) and no correlation to the estimated maximum O2 uptake. The shooting improvement is an effect of metoprolol on hand tremor. Emotional increase of heart rate and systolic blood pressure seem to be a beta 1-receptor phenomenon.

  18. Comparison of EDTA- and citric acid-enhanced phytoextraction of heavy metals in artificially metal contaminated soil by Typha angustifolia.

    Science.gov (United States)

    Muhammad, Dawood; Chen, Fei; Zhao, Jing; Zhang, Guoping; Wu, Feibo

    2009-08-01

    A pot experiment was conducted to study the performance of EDTA and citric acid (CA) addition in improving phytoextraction of Cd, Cu, Pb, and Cr from artificially contaminated soil by T. angustifolia. T. angustifolia showed the remarkable resistance to heavy metal toxicity with no visual toxic symptom including chlorosis and necrosis when exposed to metal stress. EDTA-addition significantly reduced plant height and biomass, compared with the control, and stunted plant growth, while 2.5 and 5 mM CA addition induced significant increases in root dry weight. EDTA, and 5 and 10 mM CA significantly increased shoot Cd, Pb, and Cr concentrations compared with the control, with EDTA being more effective. At final harvest, the highest shoot Cd, Cr, and Pb concentrations were recorded in the treatment of 5 mM EDTA addition, while maximal root Pb concentration was found at the 2.5 mM CA treatment. However, shoot Cd accumulation in the 10 mM CA treatment was 36.9% higher than that in 2.5 mM EDTA, and similar with that in 10 mM EDTA. Shoot Pb accumulation was lower in 10 mM CA than that in EDTA treatments. Further, root Cd, Cu, and Pb accumulation of CA treatments and shoot Cr accumulation in 5 or 10 mM CA treatments were markedly higher than that of control and EDTA treatments. The results also showed that EDTA dramatically increased the dissolution of Cu, Cr, Pb, and Cd in soil, while CA addition had less effect on water-soluble Cu, Cr, and Cd, and no effect on Pb levels. It is suggested that CA can be a good chelator candidate for T. angustifolia used for environmentally safe phytoextraction of Cd and Cr in soils.

  19. Impact of lead tolerant plant growth promoting rhizobacteria on growth, physiology, antioxidant activities, yield and lead content in sunflower in lead contaminated soil.

    Science.gov (United States)

    Saleem, Muhammad; Asghar, Hafiz Naeem; Zahir, Zahir Ahmad; Shahid, Muhammad

    2018-03-01

    Present study was conducted to evaluate the effect of lead tolerant plant growth promoting rhizobacteria (LTPGPR) on growth, physiology, yield, antioxidant activities and lead uptake in sunflower in soil contaminated with lead under pot conditions. Three pre-characterized LTPGP strains (S2 (Pseudomonas gessardii strain BLP141), S5 (Pseudomonas fluorescens A506) and S10 (Pseudomonas fluorescens strain LMG 2189)) were used to inoculate sunflower growing in soil contaminated with different levels (300, 600 and 900 mg kg -1 ) of lead by using lead nitrate salt as source of lead. Treatments were arranged according to completely randomized design with factorial arrangements. At harvesting, data regarding growth attributes (root shoot length, root shoot fresh and dry weights), yield per plant, physiological attributes (Chlorophyll 'a', 'b' and carotenoids content), antioxidant activities (Ascorbate peroxidase, catalase, superoxide dismutase and glutathione reductase), proline and malanodialdehyde content, and lead content in root, shoot and achenes of sunflower were recorded. Data were analysed by standard statistical procedures. Results showed that lead contamination reduced the plants growth, physiology and yield at all levels of lead stress. But application of LTPGPR in soil contaminated with lead improved plant growth, physiology, yield, and antioxidant activities, proline, and reduced the malanodialdehyde content (that is reduced by the application of different strains in lead contamination) of sunflower as compared to plants grown in soil without inoculation. Inoculation also promoted the uptake of lead in root, shoots and reduced the uptake of lead in achenes of plants as compared to plants in lead contamination without inoculation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Influence of plants on the distribution and composition of PBDEs in soils of an e-waste dismantling area: Evidence of the effect of the rhizosphere and selective bioaccumulation

    International Nuclear Information System (INIS)

    Wang, Yan; Luo, Chunling; Li, Jun; Yin, Hua; Zhang, Gan

    2014-01-01

    Rhizosphere effects on the distribution of PBDEs in e-waste contaminated soils were investigated. The geometric means of the PBDEs in the rhizosphere and non-rhizosphere soils were 32.6 ng/g and 12.2 ng/g, whereas the geometric means of the PBDEs in vegetable shoots and roots were 2.15 ng/g and 3.02 ng/g, respectively. PBDEs in soil at different distances from the root surface may first rise appreciably and then decrease to a non-rhizosphere level for long-term contaminated soils. Different PBDE compositions in roots and shoots indicated that PBDEs in shoots may be mainly taken up from the air. The ratios of BDE99/100 and BDE153/154 in plants and their corresponding soils were different. The bioaccumulations of BDEs 100 and 154 were much higher than those of BDEs 99 and 153, respectively. This indicated that the bioaccumulation was selective and influenced by the substitution pattern, with ortho-substituted isomers being more prevalent than meta-substituted isomers. -- Highlights: • PBDEs in rhizosphere soils were higher than those in non-rhizosphere soils. • PBDEs in soil may first be accumulated and then reduced towards root surface. • Bioaccumulation of PBDEs is selective and influenced by substituent effect. • Bioaccumulations of BDEs 100 and 154 were much higher than BDEs 99 and 153. -- The bioaccumulation of PBDE isomers was selective and influenced by the substituent effect, with ortho-substitution being favored over meta-substitution

  1. Relationship between the shoot characteristics and plant resistance to vascular-streak dieback on cocoa

    Directory of Open Access Journals (Sweden)

    Agung Wahyu Soesilo

    2014-12-01

    Full Text Available Vascular-streak dieback (Oncobasidium theobromae is a serious disease on cocoa damaging the vegetative tissue especially on the branches and leaves. This research was aimed to identify the relationship between characteristics of sprouting ability and VSD resistance to confirm the response of cocoa to pruning treatment on VSD control and developing criteria for selection. Trial was carried out at Kaliwining Experimental Station of ICCRI, a VSD-endemic area by using 668 plants of hybrid populayion which were derivated from intercrossing among seven clones performing different response to VSD. The resistance was evaluated by scoring the plant damage with the scale of 0-6 on drought season in the year of 2009 and 2011. The characteristics of sprouting ability was assessed by recording the pruned trees for the variables of the number of re-growth shoot, shoot height, number of new shoot per pruned branches, shoot diameter and number of leaves per shoot. It was analyzed that the variables of the number of shoot per pruned branches, shoot diameter, shoot height and number of leaves per shoot were not significantly correlated to the score of VSD damage. Grouping of the resistance also performed similar results whereas mean of the sprouting variables were not different among group but the percentage of sprouted branches tend to be higher with the higher of the resistance (lower score. This result confirmed any mechanism of tolerance on VSD resistance by accelerating shoot rejuvenation on resistant plant. Key words : vascular-streak diaback, cocoa, resistance, characteristics of sprouting

  2. Seedling growth of Adenanthera pavonina L. in polluted soils of ...

    African Journals Online (AJOL)

    The seedling growth performance of Adenanthera pavonina L. in polluted soils of different railway tracks viz. Karachi Cantt. Station, Malir Halt, Malir 15, Landhi Junction and University Campus (control) was studied under in pots under natural field conditions. The results showed that the root, shoot and seedling size, number ...

  3. Multisurface modeling of Ni bioavailability to wheat (Triticum aestivum L.) in various soils.

    Science.gov (United States)

    Zhao, Xiaopeng; Jiang, Yang; Gu, Xueyuan; Gu, Cheng; Taylor, J Anita; Evans, Les J

    2018-07-01

    Continual efforts have been made to determine a simple and universal method of estimating heavy metal phytoavailability in terrestrial systems. In the present study, a mechanism-based multi-surface model (MSM) was developed to predict the partition of Ni(II) in soil-solution phases and its bioaccumulation in wheat (Triticum aestivum L.) in 19 Chinese soils with a wide range of soil properties. MSM successfully predicted the Ni(II) dissolution in 0.01 M CaCl 2 extracting solution (R 2  = 0.875). The two-site model for clay fraction improved the prediction, particularly for alkaline soils, because of the additional consideration of edge sites. More crucially, the calculated dissolved Ni(II) was highly correlated with the metal accumulation in wheat (R 2  = 0.820 for roots and 0.817 for shoots). The correlation coefficients for the MSM and various chemical extraction methods have the following order: soil pore water > MSM ≈ diffuse gradient technique (DGT) > soil total Ni > 0.43 M HNO 3  > 0.01 M CaCl 2 . The results suggested that the dissolved Ni(II) calculated using MSM can serve as an effective indicator of the bioavailability of Ni(II) in various soils; hence, MSM can be used as an supplement for metal risk prediction and assessment besides chemical extraction techniques. Copyright © 2018 Elsevier Ltd. All rights reserved.

  4. Range shifts and global warming: ecological responses of Empetrum nigrum L. to experimental warming at its northern (high Arctic) and southern (Atlantic) geographical range margin

    International Nuclear Information System (INIS)

    Buizer, Bert; Weijers, Stef; Van Bodegom, Peter M; Van Breda, Johan; De Korte, Maarten; Van Rijckevorsel, Jaap; Rozema, Jelte; Alsos, Inger Greve; Eidesen, Pernille Bronken

    2012-01-01

    Global change is expected to lead to range shifts of plant species. The ecological mechanisms underpinning these shifts are currently not well understood. Here, we compared ecological responses possibly underlying southern range contraction and northern range expansion of Empetrum nigrum, a key species in northern heathlands, which may be related to global change. We hypothesized a negative response to warming in the ‘south’ (i.e. the Netherlands) and a positive response at the northern range margin (the tundra on Svalbard). Open top chambers (OTCs) were used to simulate global warming. In the ‘south’, OTC warming caused enhanced shoot growth and growth rate, biomass increment, advanced phenology, larger and heavier berries of Empetrum, while its growing season was extended by 75 days. Under OTC warming co-occurring Calluna vulgaris also showed an increased growing season length (by 98 days) as well as increased shoot growth rate and biomass growth, plant cover and height. Still, we found no evidence for increased competitiveness relative to Empetrum. In the ‘north’, Empetrum responded with increased shoot and biomass growth, enhanced berry development and ripening to warming. These responses exceeded those of co-occurring Cassiope tetragona with the exception of its biomass response. The direct and indirect ecological responses found do not readily explain the observed northward retreat of Empetrum at the southern range margin. The direct ecological responses found at its northern range margin are, on the other hand, in line with the increased occurrences of this species on Svalbard. (letter)

  5. Bioavailability of Zn in ZnO nanoparticle-spiked soil and the implications to maize plants

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xueqin [Southwest University, College of Resources and Environment (China); Wang, Fayuan, E-mail: wfy1975@163.com; Shi, Zhaoyong [Henan University of Science and Technology, Agricultural College (China); Tong, Ruijian [Luoyang Normal University, Life Science Department (China); Shi, Xiaojun, E-mail: shixj@swu.edu.cn [Southwest University, College of Resources and Environment (China)

    2015-04-15

    Little is known about the relationships between Zn bioavailability in ZnO nanoparticle (NP)-spiked soil and the implications to crops. The present pot culture experiment studied Zn bioavailability in soil spiked with different doses of ZnO NPs, using the diethylenetriaminepentaacetic acid (DTPA) extraction method, as well as the toxicity and Zn accumulation in maize plants. Results showed that ZnO NPs exerted dose-dependent effects on maize growth and nutrition, photosynthetic pigments, and root activity (dehydrogenase), ranging from stimulatory (100–200 mg/kg) through to neutral (400 mg/kg) and toxic effect (800–3200 mg/kg). Both Zn concentration in shoots and roots correlated positively (P < 0.01) with ZnO NPs dose and soil DTPA-extractable Zn concentration. The BCF of Zn in shoots and roots ranged from 1.02 to 3.83 when ZnO NPs were added. In most cases, the toxic effects on plants elicited by ZnO NPs were overall similar to those caused by bulk ZnO and soluble Zn (ZnSO{sub 4}) at the same doses, irrespective of some significant differences suggesting a higher toxicity of ZnO NPs. Oxidative stress in plants via superoxide free radical production was induced by ZnO NPs at 800 mg/kg and above, and was more severe than the same doses of bulk ZnO and ZnSO{sub 4}. Although significantly lower compared to bulk ZnO and ZnSO{sub 4}, at least 16 % of the Zn from ZnO NPs was converted into DTPA-extractable (bioavailable) forms. The dissolved Zn{sup 2+} from ZnO NPs may make a dominant contribution to their phytotoxicity. Although low amounts of ZnO NPs exhibited some beneficial effects, the accumulation of Zn from ZnO NPs into maize tissues could pose potential health risks for both plants and human.

  6. Applying carbon dioxide, plant growth-promoting rhizobacterium and EDTA can enhance the phytoremediation efficiency of ryegrass in a soil polluted with zinc, arsenic, cadmium and lead.

    Science.gov (United States)

    Guo, Junkang; Feng, Renwei; Ding, Yongzhen; Wang, Ruigang

    2014-08-01

    This study was conducted to investigate the use of elevated carbon dioxide (CO2), plant growth-promoting rhizobacterium Burkholderia sp. D54 (PGPR) and ethylenediaminetetraacetic acid (EDTA) to enhance the phytoextraction efficiency of ryegrass in response to multiple heavy metal (or metalloid)-polluted soil containing zinc (Zn), arsenic (As), cadmium (Cd) and lead (Pb). All of the single or combined CO2, PGPR and EDTA treatments promoted ryegrass growth. The stimulation of ryegrass growth by CO2 and PGPR could primarily be attributed to the regulation of photosynthesis rather than decreased levels of Zn, As and Cd in the shoots. Most treatments seemed to reduce the Zn, As and Cd contents in the shoots, which might be associated with enhanced shoot biomass, thus causing a "dilution effect" regarding their levels. The combined treatments seemed to perform better than single treatments in removing Zn, As, Cd and Pb from soil, judging from the larger biomass and relatively higher total amounts (TAs) of Zn, As, Cd and Pb in both the shoots and roots. Therefore, we suggest that the CO2 plus PGPR treatment will be suitable for removing Zn, As, Cd and Pb from heavy metal (or metalloid)-polluted soils using ryegrass as a phytoremediation material. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Trace metal uptake by tropical vegetables grown on soil amended with urban sewage sludge

    Energy Technology Data Exchange (ETDEWEB)

    Nabulo, G.; Black, C.R. [School of Biosciences, University of Nottingham, University Park, Nottingham, NG7 2RD (United Kingdom); Young, S.D., E-mail: scott.young@nottingham.ac.u [School of Biosciences, University of Nottingham, University Park, Nottingham, NG7 2RD (United Kingdom)

    2011-02-15

    Trace metal uptake was measured for tropical and temperate leafy vegetables grown on soil from an urban sewage disposal farm in the UK. Twenty-four leafy vegetables from East Africa and the UK were assessed and the five vegetable types that showed the greatest Cd concentrations were grown on eight soils differing in the severity of contamination, pH and other physico-chemical properties. The range of Cd concentrations in the edible shoots was greater for tropical vegetables than for temperate types. Metal uptake was modelled as a function of (i) total soil metal concentration, (ii) CaCl{sub 2}-soluble metal, (iii) soil solution concentration and (iv) the activity of metal ions in soil pore water. Tropical vegetables were not satisfactorily modelled as a single generic 'green vegetable', suggesting that more sophisticated approaches to risk assessment may be required to assess hazard from peri-urban agriculture in developing countries. - Research highlights: Cadmium uptake by tropical green vegetables varies greatly between types. Modelling metal uptake works best for Ni, Cd and Zn but is poor for Cu, Ba and Pb. Modelling with dilute CaCl{sub 2} extraction is as good as metal ion activity in pore water. - Trace metal uptake by tropical leaf vegetables can be predicted from dilute CaCl{sub 2} extraction of soil but model parameters are genotype-specific.

  8. Trace metal uptake by tropical vegetables grown on soil amended with urban sewage sludge

    International Nuclear Information System (INIS)

    Nabulo, G.; Black, C.R.; Young, S.D.

    2011-01-01

    Trace metal uptake was measured for tropical and temperate leafy vegetables grown on soil from an urban sewage disposal farm in the UK. Twenty-four leafy vegetables from East Africa and the UK were assessed and the five vegetable types that showed the greatest Cd concentrations were grown on eight soils differing in the severity of contamination, pH and other physico-chemical properties. The range of Cd concentrations in the edible shoots was greater for tropical vegetables than for temperate types. Metal uptake was modelled as a function of (i) total soil metal concentration, (ii) CaCl 2 -soluble metal, (iii) soil solution concentration and (iv) the activity of metal ions in soil pore water. Tropical vegetables were not satisfactorily modelled as a single generic 'green vegetable', suggesting that more sophisticated approaches to risk assessment may be required to assess hazard from peri-urban agriculture in developing countries. - Research highlights: → Cadmium uptake by tropical green vegetables varies greatly between types. → Modelling metal uptake works best for Ni, Cd and Zn but is poor for Cu, Ba and Pb. → Modelling with dilute CaCl 2 extraction is as good as metal ion activity in pore water. - Trace metal uptake by tropical leaf vegetables can be predicted from dilute CaCl 2 extraction of soil but model parameters are genotype-specific.

  9. Uptake of radiocaesium by lettuce crops: the effect of K in soil solution

    International Nuclear Information System (INIS)

    Waegeneers, N.; Camps I Vila, M.; Smolders, E.; Merckx, R.; Sauras, T.; Madoz-Escande, C.

    1998-01-01

    The effect of varying K supply on 137 Cs uptake by lettuce (Lactuca sativa, cv. Batavia, Gloire du Dauphine) was studied in solution culture, in a potted soil experiment and in a greenhouse lysimeter experiment under close-to-real conditions. Lettuce was grown for 13 days in nutrient solution spiked with 137 Cs. Treatments were four concentrations of potassium in solution (25, 50, 250, and 1000 μM). Yields were marginally affected by K supply. The 137 Cs concentration factor (CF, ml/g) decreased 66-fold in the shoot and 432-fold in the roots over the whole K concentration range. The decrease was most pronounced between 25 and 250 μM K. In a subsequent experiment, lettuce was grown for 20 days under the same climatic conditions in two sandy-foam soils (A, B) contaminated with 134 Cs. Both had similar characteristics but differed widely in K supply. Soil solution K concentrations were 100 μM (A) or 3000 μM (B). The radiocesium soil-to-plant Transfer Factor (TF, g plant dry weight / g soil) was 0.320 in soil A and 0.016 in soil B. The higher 137 Cs availability at the lower K supply (soil A) was contrasted by lower 137 Cs concentrations in soil solution of soil A than of soil B. Radiocesium transfer to lettuce grown to maturity was analysed on 5 different lysimeter soils under controlled climatic conditions. The soils were artificially contaminated with 137 Cs in 1994. The TF's varied between 0.032 and 0.191 and were not related to K concentrations in soil solution. The CF decreased about 100-fold with K concentrations increasing from 0.3 to 18 mM. Predictions of soil-to-plant transfer factors based on soil solution composition and nutrient solution results were qualitatively correct but underestimated the observed values

  10. Effect of EDTA and Citric Acid on Phytoextraction of Copper and Zinc from a Naturally Contaminated Soil by Maize (Zea mays L. Cultivars

    Directory of Open Access Journals (Sweden)

    A. Taheripur

    2016-09-01

    Full Text Available Introduction: Mining and smelting activities have contributed to increasing levels of copper (Cu and zinc (Zn in soils around of Sarcheshmeh copper mine (Kerman, Iran. Soil chemical analysis showed that the available of Cu and Zn (extracted with DTPA-TEA were 260.1 and 9.2 mg kg-1 soil, respectively. Phytoextraction is one of the most popular and useful phytoremediation techniques for removal of heavy metals from polluted soils. For chemically-assisted phytoextraction, different chelating agents such as EDTA and citric acid are applied to soil to increase the availability of heavy metals in soil for uptake by plants. A pot experiment was conducted to elucidate the performance of chelating agents addition in improving phytoextraction of Cu and zinc Zn from a naturally contaminated soil by maize (Zea mays L. cultivars. Materials and Methods: A factorial experiment in a completely randomized design was carried out bythree factors of chelate type, chelate concentrations and maize cultivars with three replications in 2012 at ShahreKord University. Chelating agents were Ethylene Diamine Tetra Acetic Acid (EDTA and citric acid (CA. They were applied in concentration levels of 0, 0.75 and 1.5 mmole kg-1 soil with irrigation water. The three maize cultivars used were single cross 704 (SC-704, three v cross 647 (TVC-647, and single cross 677 (SC-677. The pots were 23 cm in diameter and 23 cm deep, and were filled with 4 kg of a silty loam, calcareous soil taken from the surface layer of Sarcheshmeh copper mine area. Maize plant s was grown under greenhouse conditions over 90 days. After the harvest, soil available Cu and Zn contents (extracted with DTPA-TEA were determined by atomic absorption spectrophotometry (AAS. Plant samples (shoot and root were dried for 48 h at 70ºC to determine their dry matter content (yield. Total Cu and Zn concentrations in root and shoot of maize were measured after digestion plant samples by AAS method. The shoot and root

  11. Biochar reduces copper toxicity in Chenopodium quinoa Willd. In a sandy soil.

    Science.gov (United States)

    Buss, Wolfram; Kammann, Claudia; Koyro, Hans-Werner

    2012-01-01

    Mining, smelting, land applications of sewage sludge, the use of fungicides containing copper (Cu), and other human activities have led to widespread soil enrichment and contamination with Cu and potentially toxic conditions. Biochar (BC) can adsorb several substances, ranging from herbicides to plant-inhibiting allelochemicals. However, the range of potential beneficial effects on early-stage plant growth with regard to heavy metal toxicity is largely unexplored. We investigated the ameliorating properties of a forestry-residue BC under Cu toxicity conditions on early plant growth. Young quinoa plants () were grown in the greenhouse in the presence of 0, 2, and 4% BC application (w/w) added to a sandy soil with 0, 50, or 200 μg g Cu supplied. The plants without BC showed severe stress symptoms and reduced growth shortly after Cu application of 50 μg g and died at 200 μg Cu g. Increasing BC concentrations in the growth medium significantly increased the plant performance without Cu toxicity or under Cu stress. At the 4% BC application rate, the plants with 200 μg g Cu almost reached the same biomass as in the control treatment. In the presence of BC, less Cu entered the plant tissues, which had reduced Cu concentrations in the order roots, shoots, leaves. The amelioration effect also was reflected in the plant-soil system CO gas exchange, which showed clear signs of improvement with BC presence. The most likely ameliorating mechanisms were adsorption of Cu to negatively charged BC surfaces and an improvement of the water supply. Overall, BC seems to be a beneficial amendment with the potential to ameliorate Cu toxicity in sandy soils. Further research with a broad spectrum of different soil types, BCs, and crop plants is required. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  12. Growth and phenology of three dwarf shrub species in a six-year soil warming experiment at the alpine treeline.

    Science.gov (United States)

    Anadon-Rosell, Alba; Rixen, Christian; Cherubini, Paolo; Wipf, Sonja; Hagedorn, Frank; Dawes, Melissa A

    2014-01-01

    Global warming can have substantial impacts on the phenological and growth patterns of alpine and Arctic species, resulting in shifts in plant community composition and ecosystem dynamics. We evaluated the effects of a six-year experimental soil warming treatment (+4°C, 2007-2012) on the phenology and growth of three co-dominant dwarf shrub species growing in the understory of Larix decidua and Pinus uncinata at treeline in the Swiss Alps. We monitored vegetative and reproductive phenology of Vaccinium myrtillus, Vaccinium gaultherioides and Empetrum hermaphroditum throughout the early growing season of 2012 and, following a major harvest at peak season, we measured the biomass of above-ground ramet fractions. For all six years of soil warming we measured annual shoot growth of the three species and analyzed ramet age and xylem ring width of V. myrtillus. Our results show that phenology of the three species was more influenced by snowmelt timing, and also by plot tree species (Larix or Pinus) in the case of V. myrtillus, than by soil warming. However, the warming treatment led to increased V. myrtillus total above-ground ramet biomass (+36% in 2012), especially new shoot biomass (+63% in 2012), as well as increased new shoot increment length and xylem ring width (+22% and +41%, respectively; average for 2007-2012). These results indicate enhanced overall growth of V. myrtillus under soil warming that was sustained over six years and was not caused by an extended growing period in early summer. In contrast, E. hermaphroditum only showed a positive shoot growth response to warming in 2011 (+21%), and V. gaultherioides showed no significant growth response. Our results indicate that V. myrtillus might have a competitive advantage over the less responsive co-occurring dwarf shrub species under future global warming.

  13. Growth and phenology of three dwarf shrub species in a six-year soil warming experiment at the alpine treeline.

    Directory of Open Access Journals (Sweden)

    Alba Anadon-Rosell

    Full Text Available Global warming can have substantial impacts on the phenological and growth patterns of alpine and Arctic species, resulting in shifts in plant community composition and ecosystem dynamics. We evaluated the effects of a six-year experimental soil warming treatment (+4°C, 2007-2012 on the phenology and growth of three co-dominant dwarf shrub species growing in the understory of Larix decidua and Pinus uncinata at treeline in the Swiss Alps. We monitored vegetative and reproductive phenology of Vaccinium myrtillus, Vaccinium gaultherioides and Empetrum hermaphroditum throughout the early growing season of 2012 and, following a major harvest at peak season, we measured the biomass of above-ground ramet fractions. For all six years of soil warming we measured annual shoot growth of the three species and analyzed ramet age and xylem ring width of V. myrtillus. Our results show that phenology of the three species was more influenced by snowmelt timing, and also by plot tree species (Larix or Pinus in the case of V. myrtillus, than by soil warming. However, the warming treatment led to increased V. myrtillus total above-ground ramet biomass (+36% in 2012, especially new shoot biomass (+63% in 2012, as well as increased new shoot increment length and xylem ring width (+22% and +41%, respectively; average for 2007-2012. These results indicate enhanced overall growth of V. myrtillus under soil warming that was sustained over six years and was not caused by an extended growing period in early summer. In contrast, E. hermaphroditum only showed a positive shoot growth response to warming in 2011 (+21%, and V. gaultherioides showed no significant growth response. Our results indicate that V. myrtillus might have a competitive advantage over the less responsive co-occurring dwarf shrub species under future global warming.

  14. Fruit production and branching density affect shoot and whole-tree wood to leaf biomass ratio in olive.

    Science.gov (United States)

    Rosati, Adolfo; Paoletti, Andrea; Al Hariri, Raeed; Famiani, Franco

    2018-02-14

    The amount of shoot stem (i.e., woody part of the shoot) dry matter per unit shoot leaf dry matter (i.e., the shoot wood to leaf biomass ratio) has been reported to be lower in short shoots than in long ones, and this is related to the greater and earlier ability of short shoots to export carbon. This is important in fruit trees, since the greater and earlier carbon export ability of shoots with a lower wood to leaf biomass ratio improves fruit production. This ratio may vary with cultivars, training systems or plant age, but no study has previously investigated the possible effect of fruit production. In this study on two olive cultivars (i.e., Arbequina, with low growth rate, and Frantoio, with high growth rate) subject to different fruit production treatments, we found that at increasing fruit production, shoot length and shoot wood to leaf biomass ratio were proportionally reduced in the new shoots growing at the same time as the fruit. Specifically, fruit production proportionally reduced total new-shoot biomass, length, leaf area and average shoot length. With decreasing shoot length, shoot diameter, stem mass, internode length, individual leaf area and shoot wood to leaf biomass ratio also decreased. This may be viewed as a plant strategy to better support fruit growth in the current year, given the greater and earlier ability of short shoots to export carbon. Moreover, at the whole-tree level, the percentage of total tree biomass production invested in leaves was closely correlated with branching density, which differed significantly across cultivars. By branching more, Arbequina concentrates more shoots (thus leaves) per unit of wood (trunk, branches and root) mass, decreasing wood to leaf biomass ratio at the whole-tree level. Therefore, while, at the shoot level, shoot length determines shoot wood to leaf biomass ratio, at the canopy level branching density is also an important determinant of whole-tree wood to leaf biomass ratio. Whole-tree wood to leaf

  15. Root-shoot growth responses during interspecific competition quantified using allometric modelling.

    Science.gov (United States)

    Robinson, David; Davidson, Hazel; Trinder, Clare; Brooker, Rob

    2010-12-01

    Plant competition studies are restricted by the difficulty of quantifying root systems of competitors. Analyses are usually limited to above-ground traits. Here, a new approach to address this issue is reported. Root system weights of competing plants can be estimated from: shoot weights of competitors; combined root weights of competitors; and slopes (scaling exponents, α) and intercepts (allometric coefficients, β) of ln-regressions of root weight on shoot weight of isolated plants. If competition induces no change in root : shoot growth, α and β values of competing and isolated plants will be equal. Measured combined root weight of competitors will equal that estimated allometrically from measured shoot weights of each competing plant. Combined root weights can be partitioned directly among competitors. If, as will be more usual, competition changes relative root and shoot growth, the competitors' combined root weight will not equal that estimated allometrically and cannot be partitioned directly. However, if the isolated-plant α and β values are adjusted until the estimated combined root weight of competitors matches the measured combined root weight, the latter can be partitioned among competitors using their new α and β values. The approach is illustrated using two herbaceous species, Dactylis glomerata and Plantago lanceolata. Allometric modelling revealed a large and continuous increase in the root : shoot ratio by Dactylis, but not Plantago, during competition. This was associated with a superior whole-plant dry weight increase in Dactylis, which was ultimately 2·5-fold greater than that of Plantago. Whole-plant growth dominance of Dactylis over Plantago, as deduced from allometric modelling, occurred 14-24 d earlier than suggested by shoot data alone. Given reasonable assumptions, allometric modelling can analyse competitive interactions in any species mixture, and overcomes a long-standing problem in studies of competition.

  16. Higher concentrations of nanoscale zero-valent iron (nZVI) in soil induced rice chlorosis due to inhibited active iron transportation

    International Nuclear Information System (INIS)

    Wang, Jie; Fang, Zhanqiang; Cheng, Wen; Yan, Xiaomin; Tsang, Pokeung Eric; Zhao, Dongye

    2016-01-01

    In this study, the effects of concentrations 0, 100, 250, 500, 750 and 1000 mg kg"−"1 of nanoscale zero-valent iron (nZVI) on germination, seedlings growth, physiology and toxicity mechanisms were investigated. The results showed that nZVI had no effect on germination, but inhibited the rice seedlings growth in higher concentrations (>500 mg kg"−"1 nZVI). The highest suppression rate of the length of roots and shoots reached 46.9% and 57.5%, respectively. The 1000mg kg"−"1 nZVI caused the highest suppression rates for chlorophyll and carotenoids, at 91.6% and 85.2%, respectively. In addition, the activity of antioxidant enzymes was altered by the translocation of nanoparticles and changes in active iron content. Visible symptoms of iron deficiency were observed at higher concentrations, at which the active iron content decreased 61.02% in the shoots, but the active iron content not decreased in roots. Interestingly, the total and available amounts of iron in the soil were not less than those in the control. Therefore, the plants iron deficiency was not caused by (i) deficiency of available iron in the soil and (ii) restraint of the absorption that plant takes in the available iron, while induced by (ⅲ) the transport of active iron from the root to the shoot was blocked. The cortex tissues were seriously damaged by nZVI which was transported from soil to the root, these were proved by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS). This current study shows that the mechanism of iron deficiency in rice seedling was due to transport of active iron from the root to the shoot blocked, which was caused by the uptake of nZVI. - Highlights: • Higher concentrations of nZVI induced iron deficiency in rice seedlings visibly. • nZVI was taken in rice seedlings and transported form root to shoot. • The pathway of active iron transport from root to shoot was inhibited. • The cortex tissues

  17. Effect of Cyanobacteria Isolates on Rice Seeds Germination in Saline Soil

    Directory of Open Access Journals (Sweden)

    Mostafa M. El -Sheekh

    2018-03-01

    Full Text Available Cyanobacteria are prokaryotic photosynthetic communities which are used in biofertilization of many plants especially rice plant. Cyanobacteria play a vital role to increase the plant's ability for salinity tolerance. Salinity is a worldwide problem which affects the growth and productivity of crops. In this work three cyanobacteria strains (Nostoc calcicola, Anabaena variabilis, and Nostoc linkia were isolated from saline soil at Kafr El-Sheikh Governorate; North Egypt. The propagated cyanobacteria strains were used to withstand salinity of the soil and increase rice plant growth (Giza 178. The length of roots and shoot seedlings was measured for seven and forty days of cultivation, respectively. The results of this investigation showed that the inoculation with Nostoc calcicola, Anabaena variabilis, and Nostoc linkia increased root length by 27.0, 4.0, 3.0 % and 39, 20, 19 % in EC5 and 10 (ds/m, respectively. Similarly, they increased shoot length by 121, 70, 55 %, 116, 88, 82 % in EC5 and 10 (ds/m, respectively. In EC15and more concentrations, control rice plants could not grow while those to which cyanobacteria were inoculated could withstand only EC15 but not other elevated concentrations. These results encourage using Nostoc calcicola,Anabaena variabilis, and Nostoc linkia as biofertilizer for rice plant in the saline soil for increasing growth and decrease soil electrical conductivity.

  18. Methylation-sensitive amplification polymorphism in date palms (Phoenix dactylifera L.) and their off-shoots.

    Science.gov (United States)

    Fang, J-G; Chao, C T

    2007-07-01

    DNA methylation plays an important role in the regulation of gene expression in eukaryotes. In this study, the extent and patterns of DNA methylation were assessed in date palm mother-plants and their off-shoots using the methylation-sensitive amplified polymorphism (MSAP) technique. Three types of bands were generated using 12 pairs of primers. Type I were present in both ECOR I + HPA II and ECOR I + MSP I lanes; type II were present in ECOR I + HPA II lanes, but not in ECOR I + MSP I lanes; and type III bands were present in ECOR I + MSP I lanes, but not in ECOR I + HPA II lanes. The total numbers of these three types of bands were 782, 55, and 34, respectively. Among these three types of bands, the polymorphic bands were, respectively, 37, 10, and 0. The distribution of polymorphic bands among mother-plants and off-shoots suggests the methylation variation was present in both the mother-plants and off-shoots. Forty- four out of these 47 polymorphic bands show clear difference between mother-plant and off-shoots: 38 were present only in off-shoots and 6 in both mother-plants and off-shoots. Compared to methylation status in mother-plants, the methylation variation during off-shoot growth of date palm can be characterized as a process involving primarily de-methylation. Hypomethylation of DNA in off-shoots, compared with mother-plants, reflects the marked expression of this molecular feature, which may be related to gene expression during off-shoot development. The methylation or de-methylation status of specific loci in the mother-plants and their off-shoots were probably random events.

  19. Feasibility of phytoextraction to remediate cadmium and zinc contaminated soils.

    Science.gov (United States)

    Koopmans, G F; Römkens, P F A M; Fokkema, M J; Song, J; Luo, Y M; Japenga, J; Zhao, F J

    2008-12-01

    A Cd and Zn contaminated soil was mixed and equilibrated with an uncontaminated, but otherwise similar soil to establish a gradient in soil contamination levels. Growth of Thlaspi caerulescens (Ganges ecotype) significantly decreased the metal concentrations in soil solution. Plant uptake of Cd and Zn exceeded the decrease of the soluble metal concentrations by several orders of magnitude. Hence, desorption of metals must have occurred to maintain the soil solution concentrations. A coupled regression model was developed to describe the transfer of metals from soil to solution and plant shoots. This model was applied to estimate the phytoextraction duration required to decrease the soil Cd concentration from 10 to 0.5 mg kg(-1). A biomass production of 1 and 5 t dm ha(-1) yr(-1) yields a duration of 42 and 11 yr, respectively. Successful phytoextraction operations based on T. caerulescens require an increased biomass production.

  20. Elicitation effects of synthetic 1,2,4,5-tetraoxane and 2,5-diphenyltiophene in shoot cultures of two Nepeta species

    Directory of Open Access Journals (Sweden)

    Dmitrović Slavica

    2016-01-01

    Full Text Available The present study was aimed to investigate the elicitation possibility of the main secondary metabolites production in Nepeta cataria L. and N. pannonica L. plants, by exposing them to synthetic compounds from the group of tetraoxanes and tiophenes. The effect of DO63 (1,2,4,5-tetraoxane and DOVF15 (2,5-diphenyl-tiophene on the production of cis,trans-nepetalactone (NL and rosmarinic acid (RA in two Nepeta species, was investigated in shoots grown on culture medium with addition of synthetic compounds in concentrations ranging from 0.1 to 2 mg L-1. The content of targeted metabolites in tested in vitro shoots depended on the type and the concentration of applied synthetic compounds. Application of DO63, primarily in concentration of 0.1 mg L-1 to 1 mg L-1, affected only NL production in both Nepeta species resulting in increased NL content in treated shoots, while production of RA was not influenced. Addition of DOVF15 caused decrease of RA content in N. pannonica shoots and increase in N. cataria shoots, whereas NL production was not affected. The presented results highlight the possibility of DO63 and DOVF15 application for the elicitation of the main secondary metabolites production in species from the genus Nepeta. [Projekat Ministarstva nauke Republike Srbije, br. 172008 i br. 173024