DOCSLIB.ORG

Delayed Fluorescence Imaging of Photosynthesis Inhibitor and Heavy Metal Induced Stress in Potato

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Delayed Fluorescence Imaging of Photosynthesis Inhibitor and Heavy Metal Induced Stress in Potato Cent. Eur. J. Biol. • 7(3) • 2012 • 531-541 DOI: 10.2478/s11535-012-0038-z Central European Journal of Biology Delayed fluorescence imaging of photosynthesis inhibitor and heavy metal induced stress in potato Research Article Jaka Razinger1,*, Luka Drinovec2, Maja Berden-Zrimec3 1Agricultural Institute of Slovenia, 1000 Ljubljana, Slovenia 2Aerosol d.o.o., 1000 Ljubljana, Slovenia 3Institute of Physical Biology, 1000 Ljubljana, Slovenia Received 09 November 2011; Accepted 13 March 2012 Abstract: Early chemical-induced stress in Solanum tuberosum leaves was visualized using delayed fluorescence (DF) imaging. The ability to detect spatially heterogeneous responses of plant leaves exposed to several toxicants using delayed fluorescence was compared to prompt fluorescence (PF) imaging and the standard maximum fluorescence yield of PSII measurements (Fv/Fm). The toxicants used in the study were two photosynthesis inhibitors (herbicides), 100 μM methyl viologen (MV) and 140 μM diuron (DCMU), and two heavy metals, 100 μM cadmium and 100 μM copper. The exposure times were 5 and 72 h. Significant photosynthesis-inhibitor effects were already visualized after 5 h. In addition, a significant reduction in the DF/PF index was measured in DCMU- and MV-treated leaves after 5 h. In contrast, only DCMU-treated leaves exhibited a significant decrease in Fv/Fm after 5 h. All treatments resulted in a significant decrease in the DF/PF parameter after 72 h of exposure, when only MV and Cd treatment resulted in visible symptoms. Our study highlights the power of delayed fluorescence imaging. Abundant quantifiable spatial information was obtained with the instrumental setup. Delayed fluorescence imaging has been confirmed as a very responsive and useful technique for detecting stress induced by photosynthesis inhibitors or heavy metals. Keywords: Cadmium • Chlorophyll fluorescence • Copper • Diuron • EMCCD camera • Heavy metals • Herbicides • Paraquat • Photosynthesis inhibitors • Solanum tuberosum • Visualization © Versita Sp. z o.o. Abbreviations MV - 1,1′-Dimethyl-4,4′-bipyridinium dichloride, methyl viologen (syn. paraquat) DCMU - 3-(3,4-dichlorophenyl)-1,1-dimethylurea, diuron PAM - pulse amplitude modulation DF - delayed fluorescence PAR - photosynthetically active radiation DMSO - dimethyl sulfoxide PF - prompt fluorescence EMCCD - electron-multiplying charge-coupled device F0 - minimal fluorescence from dark-adapted leaf Fm - maximum fluorescence from dark-adapted 1. Introduction leaf Fv - variable fluorescence measured in dark- The introduction of non-invasive optical techniques adapted plant, Fv=Fm−F0 to biological research has significantly decreased Fv / Fm - maximum fluorescence yield of PSII, errors caused by sample manipulation and subjective Fv/Fm=(Fm−F0)/Fm interpretation of complex findings. Imaging has LED - light-emitting diode additionally improved analysis of higher plants because * E-mail: [email protected] 531 Delayed fluorescence imaging of photosynthesis inhibitor and heavy metal induced stress in potato the molecular and physiological processes that alter the photosynthesis inhibitors: methyl viologen (MV, also yield of chlorophyll fluorescence can vary substantially known as paraquat) and diuron (DCMU), as well as over the leaf surface [1]. Because of the spatial two heavy metals: cadmium and copper. DCMU affects heterogeneity in leaf response to infection, imaging the acceptor side of PSII, where it competes with and its analysis are extremely important for reasonable plastoquinone and plastoquinol for the QB binding site, determination of various stresses [2,3]. This is especially preventing electron flow between photosystem II (PSII) crucial for early detection of infection, when fast action and the plastoquinone pool [22]. This inhibition of the prevents the spread of disease. slow components of DF results in faster decay of DF Although there are numerous studies of higher plants [11]. MV acts as an electron acceptor from PSI and using prompt fluorescence imaging [1,4], only a few transfers the electrons to molecular oxygen-producing publications deal with delayed fluorescence imaging. reactive oxygen species (ROS) [23]. It is believed Bennoun and Beal [5] successfully screened algal that copper binds to PSII [24] and inhibits protein mutant colonies with an altered thylakoid electrochemical synthesis in chloroplasts as well as the reactions of the gradient using delayed fluorescence digital imaging. Calvin cycle [25,26]. As a transition metal, it can also Flor-Henry et al. [6] imaged delayed fluorescence from a participate in Fenton chemistry, producing ROS, which leaf surface; however, their research was preferentially can damage biological macromolecules [27]. Cadmium aimed toward ultra-weak luminescence from damaged interferes with the oxygen-evolving complex in PSII, leaves. Early works on DF visualization dealt with the plastoquinone pool, and ribulose-1,5-bisphosphate damage to the photosynthetic system caused by viruses, carboxylase oxygenase (RubisCo) synthesis [28,29]. It insects, temperature extremes, ultraviolet radiation, is not a redox active-transition metal, but can indirectly or herbicides [7], whereas Ellenson and Amundson expedite ROS production by substituting an essential [8] investigated the spatial distribution and temporal micronutrient (e.g., disturbing Fe homeostasis; [30]) development of plant stress using DF visualization. or binding non-specifically to thiol groups, thereby There are several differences between delayed and disturbing various metabolic processes [31]. prompt fluorescence. Delayed fluorescence (DF) is a Our aims were (a) to assess whether delayed long-lived (from milliseconds to seconds) low-level photon fluorescence can be accurately visualized to enable emission from plant tissue after a short illumination pulse quantification, and (b) to determine whether delayed [9]. During the illumination, charge pairs are generated in fluorescence imaging makes it possible to see a spatially photosystem II (PSII), with positive charges located on heterogeneous response of plant leaves to stress induced the oxygen-evolving complex and negative charges on by either photosynthesis inhibitors or heavy metals. In the quinone acceptors (QA and QB). The slow components addition, a quotient of DF and PF images was calculated of DF originate in back reactions between the S2 and S3 to provide a normalized photosynthetic stress parameter. states of the oxygen-evolving complex and quinones QA and QB [10]. The half-times of these reactions in isolated chloroplasts are 1 to 2 s for QA+S2/3 and approximately 2. Experimental Procedures 25 s for QB+S2/3 [11]. Prompt fluorescence (PF), on the other hand, originates in the radiative de-excitation of 2.1 Plant material and exposure to the excited chlorophyll molecules before charge separation chemicals tested emitted in the nanosecond time range. DF is affected The experiments were performed on excised leaves by chemical and physical parameters, such as various of Solanum tuberosum L. var. Sante [32]. The plants chemicals and metals [12-16], temperature [17], or were grown from tissue culture. They were kept in a nutrient status [18]. The intensity of delayed fluorescence growth chamber at 21±1°C, 70±2% relative humidity, has been reported to be a measure of photosynthetic under cool white fluorescent light (160 µmol −2 m s−1 activity [19]. DF decay kinetics depend on the rates of back photosynthetically active radiation, PAR) with a light:dark reactions in the electron backflow in the photosynthesis cycle of 18:6 h. When the plants were 6 weeks old, fully electron transport chain [12,20]. These differences in the matured leaves from the middle-top of the canopy were physiology of the DF and PF result in some advantages of cut and their petioles inserted into 4 ml cuvettes filled DF-based parameters over PF: the DF signal can change with previously prepared dilutions of the chemicals by a factor of 10 or more, whereas the PF parameters tested in half-strength Steinberg growth medium [33]. would change by a factor of about three during certain The cuvettes with the leaves were then sealed with fluorescence measurements [21]. parafilm to minimize evaporation and put into the growth To see the effect on the photosynthetic apparatus chamber. After 5 or 72 h the leaves were removed from of Solanum tuberosum leaves, we applied two the test cuvettes and the leaf stalks washed with distilled 532 J. Razinger et al. water, put into fresh half-strength Steinberg growth connected to an illumination ring to ensure optimal and medium, and placed in darkness. homogenous sample illumination. The LED module was powered by two different current generators to obtain 2.2 Chemicals 100 μmol m−2 s−1 PAR and 0.13 μmol m−2 s−1 PAR for the All chemicals were purchased from Sigma (distributor: HIGH/LOW light options. Images were captured by an Mikro + Polo d.o.o., Maribor, Slovenia), unless stated EMCCD camera (L3Vision CCD65, e2v Technologies, otherwise. They were of the highest commercially Chelmsford, UK) Peltier cooled to −5°C, equipped with a available grade possible, 99% or more pure. The 12.0 mm focal-length compact VIS-NIR Lens (Schneider, following stock solutions were prepared: 7 mM DCMU Edmund Optics, Barrington, NJ, USA) and a 635 nm (3-(3,4-dichlorophenyl)-1,1-dimethylurea; also known long-pass filter (Semrock FF01-635/LP-25, New York, as diuron) in dimethyl sulfoxide (DMSO; Kemika, NY, USA). Frame-grabber (MovieBox Deluxe, Pinnacle Zagreb, Croatia), 10 mM
Load more

Recommended publications
  • 2,4-Dichlorophenoxyacetic Acid
    2,4-Dichlorophenoxyacetic acid 2,4-Dichlorophenoxyacetic acid IUPAC (2,4-dichlorophenoxy)acetic acid name 2,4-D Other hedonal names trinoxol Identifiers CAS [94-75-7] number SMILES OC(COC1=CC=C(Cl)C=C1Cl)=O ChemSpider 1441 ID Properties Molecular C H Cl O formula 8 6 2 3 Molar mass 221.04 g mol−1 Appearance white to yellow powder Melting point 140.5 °C (413.5 K) Boiling 160 °C (0.4 mm Hg) point Solubility in 900 mg/L (25 °C) water Related compounds Related 2,4,5-T, Dichlorprop compounds Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) 2,4-Dichlorophenoxyacetic acid (2,4-D) is a common systemic herbicide used in the control of broadleaf weeds. It is the most widely used herbicide in the world, and the third most commonly used in North America.[1] 2,4-D is also an important synthetic auxin, often used in laboratories for plant research and as a supplement in plant cell culture media such as MS medium. History 2,4-D was developed during World War II by a British team at Rothamsted Experimental Station, under the leadership of Judah Hirsch Quastel, aiming to increase crop yields for a nation at war.[citation needed] When it was commercially released in 1946, it became the first successful selective herbicide and allowed for greatly enhanced weed control in wheat, maize (corn), rice, and similar cereal grass crop, because it only kills dicots, leaving behind monocots. Mechanism of herbicide action 2,4-D is a synthetic auxin, which is a class of plant growth regulators.
    [Show full text]
  • INDEX to PESTICIDE TYPES and FAMILIES and PART 180 TOLERANCE INFORMATION of PESTICIDE CHEMICALS in FOOD and FEED COMMODITIES
    US Environmental Protection Agency Office of Pesticide Programs INDEX to PESTICIDE TYPES and FAMILIES and PART 180 TOLERANCE INFORMATION of PESTICIDE CHEMICALS in FOOD and FEED COMMODITIES Note: Pesticide tolerance information is updated in the Code of Federal Regulations on a weekly basis. EPA plans to update these indexes biannually. These indexes are current as of the date indicated in the pdf file. For the latest information on pesticide tolerances, please check the electronic Code of Federal Regulations (eCFR) at http://www.access.gpo.gov/nara/cfr/waisidx_07/40cfrv23_07.html 1 40 CFR Type Family Common name CAS Number PC code 180.163 Acaricide bridged diphenyl Dicofol (1,1-Bis(chlorophenyl)-2,2,2-trichloroethanol) 115-32-2 10501 180.198 Acaricide phosphonate Trichlorfon 52-68-6 57901 180.259 Acaricide sulfite ester Propargite 2312-35-8 97601 180.446 Acaricide tetrazine Clofentezine 74115-24-5 125501 180.448 Acaricide thiazolidine Hexythiazox 78587-05-0 128849 180.517 Acaricide phenylpyrazole Fipronil 120068-37-3 129121 180.566 Acaricide pyrazole Fenpyroximate 134098-61-6 129131 180.572 Acaricide carbazate Bifenazate 149877-41-8 586 180.593 Acaricide unclassified Etoxazole 153233-91-1 107091 180.599 Acaricide unclassified Acequinocyl 57960-19-7 6329 180.341 Acaricide, fungicide dinitrophenol Dinocap (2, 4-Dinitro-6-octylphenyl crotonate and 2,6-dinitro-4- 39300-45-3 36001 octylphenyl crotonate} 180.111 Acaricide, insecticide organophosphorus Malathion 121-75-5 57701 180.182 Acaricide, insecticide cyclodiene Endosulfan 115-29-7 79401
    [Show full text]
  • Evidence for Different Binding Sites on the 33-Kda Protein for DCMU, Atrazine and QB
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Elsevier - Publisher Connector Volume 167, number 2 FEBS 1259 February 1984 Evidence for different binding sites on the 33-kDa protein for DCMU, atrazine and QB Chantal Astier, Alain Boussac and Anne-Lise Etienne Laboratoire de PhotosynthPse, CNRS, BP I, 91190 Gifsur-Yvette, France Received 21 November 1983; revised version received 4 January 1984 Two DCMU-resistant strains of the cyanobacterium Synechocystis 6714 were used to analyse the binding sites of DCMU, atrazine and QB. DCMU’-11~was DCMU and atrazine resistant; it presented an impaired electron flow and its 33-kDa protein was weakly attached to the membrane. DCMU’-IIB, derived from the former, simultaneously regained atrazine sensitivity, normal electron flow and a tight linkage of the 33-kDa protein to the membrane. This mutant shows that loss of DCMU binding does not necessarily affect the binding of either atrazine or QB. The role of the 33-kDa protein is discussed. Cyanobacteria Mutant Herbicide Photosynthesis Photosystem ZZ 1. INTRODUCTION that a specific attack of lysine residues resulted also in a partial release of inhibition by SN58132, Electron transfer on the acceptor side of a DCMU-type inhibitor [17]. Photosystem II occurs through a primary acceptor Radioactivity labelling experiments were used to QA [l] (a particular plastoquinone of the general demonstrate a competition between DCMU and pool [2] closely associated with the chlorophyll atrazine [6,18-201. A similar competition was pro- center), a secondary acceptor Qn [3] bound to its posed in [l l] between DCMU and QB.
    [Show full text]
  • Interactions of Paraquat and Nitrodiphenylether Herbicides with the Chloroplast Photosynthetic Electron Transport in the Activation of Toxic Oxygen Species
    INTERACTIONS OF PARAQUAT AND NITRODIPHENYLETHER HERBICIDES WITH THE CHLOROPLAST PHOTOSYNTHETIC ELECTRON TRANSPORT IN THE ACTIVATION OF TOXIC OXYGEN SPECIES by Brad Luther Upham Dissertation submitted to the Faculty of the Virginia Polytechnic Institute and State University in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Plant Physiology APPROVED: Kriton K. Hatzios, Chairman -----..------,,...-r---~---------J ohn L. Hess Joyce G. Foster Laurence D. Moore David M. Orcutt William E. Winner INTERACTIONS OF PARAQUAT AND.NITRODIPHENYLETHER HERBICIDES WITH THE PHOTOSYNTHETIC ELECTRON TRANSPORT IN THE ACTIVATION OF TOXIC OXYGEN SPECIES by Brad Luther Upham Kriton K. Hatzios, Chairman Plant Physiology (ABSTRACT) The interactions of paraquat (methylviologen) and diphenylether her- bicides with the Mehler reaction as investigated. Sera from two differ- ent rabbits (RSl & RS2) were examined for their patterns of inhibition of the photosynthetic electron transport (PET) system. Serum from RS2 was greatly hemolyzed. Fifty ul of RSI serum were required for 100% inhibi- tion of a 1120 --> methylviologen(MV)/02 reaction, whereas only 10 µl of a 1:10 dilution of RS2 were needed for 100% inhibition. The ~-globulin fraction from purified rabbit serum (RSl) did not inhibit PET, indicat- ing that the antibody fraction of the rabbit serum does not contain the inhibitor. It appears that the inhibitor is from the hemolyzed red blood cells. Rabbit sera, added to chloroplast preparations prior illu- mination, caused no inhibition of a 1120 --> MV/02 reaction while addi- tion of rabbit sera during illumination inhibited the 1120 --> MV/02 reaction within 1-3 s. Various Hill reactions were used to determine the site of inhibition.
    [Show full text]
  • Environmental Health Criteria 39 PARAQUAT and DIQUAT
    Environmental Health Criteria 39 PARAQUAT AND DIQUAT Please note that the layout and pagination of this web version are not identical with the printed version. Paraquat and diquat (EHC 39, 1984) INTERNATIONAL PROGRAMME ON CHEMICAL SAFETY ENVIRONMENTAL HEALTH CRITERIA 39 PARAQUAT AND DIQUAT This report contains the collective views of an international group of experts and does not necessarily represent the decisions or the stated policy of the United Nations Environment Programme, the International Labour Organisation, or the World Health Organization. Published under the joint sponsorship of the United Nations Environment Programme, the International Labour Organisation, and the World Health Organization World Health Orgnization Geneva, 1984 The International Programme on Chemical Safety (IPCS) is a joint venture of the United Nations Environment Programme, the International Labour Organisation, and the World Health Organization. The main objective of the IPCS is to carry out and disseminate evaluations of the effects of chemicals on human health and the quality of the environment. Supporting activities include the development of epidemiological, experimental laboratory, and risk-assessment methods that could produce internationally comparable results, and the development of manpower in the field of toxicology. Other activities carried out by the IPCS include the development of know-how for coping with chemical accidents, coordination of laboratory testing and epidemiological studies, and promotion of research on the mechanisms of the biological action of chemicals. ISBN 92 4 154099 4 The World Health Organization welcomes requests for permission to reproduce or translate its publications, in part or in full. Applications and enquiries should be addressed to the Office of Publications, World Health Organization, Geneva, Switzerland, which will be glad to provide the latest information on any changes made to the text, plans for new editions, and reprints and translations already available.
    [Show full text]
  • Classification of Herbicides
    Title of the course : Weed Management Credit: 3(2+1) Class : 3rd Year IInd Semester Title of the topic : Principles of weed management College : Krishi vigyan Kendra,College of Agriculture, Rewa, JNKVV, Jabalpur Name of Teacher : Dr. (Mrs.) Smita Singh Classification of Herbicides Herbicides: Chemical method of weed control is very effective in certain cases and have great scope provided the herbicides are cheap, efficient and easily available. The chemicals used for killing the weeds or inhibiting growth of weeds are called herbicides (Weedicides). Classification of Herbicides: Herbicides are classified in different ways: A) First Group Chemical Herbicides: I) Classification of herbicides according to chemical composition. II) Classification of herbicides according to their use. III) Classification of herbicides based on time of application. IV) Classification of herbicides according to Formulation. V) Classification of herbicides according to residual effect. B) Second Group – Bio herbicides C) Third Group herbicidal mixtures. Classification of herbicide I) Classification of Herbicide Based on Chemical Nature or Composition Compounds having chemical affinities are grouped together. This is useful in liting and characterising herbicides. i) Inorganic Herbicides:Contain no carbon actions in their molecules. These were the first chemicals used for weed control before the introduction of the organic compounds, example are: a) Acids:Arsenic acid, arsenious acid, arsenic trioxide sulphuric acid. b) Salts:Borax, copper sulphate, ammonium sulphate, Na chlorate , Na arsenite , copper nitrate. ii) Organic Herbicides:Oils and non oils contain carbon and hydrogen in their molecules. a) Oils: Diesel oil, standard solvent, xylene-type, aromatic oils, polycyclic , aromatic oils etc. b) Aliphatics:Dalapon, TCA, Acrolein, Glyphosphate methyl bromide.
    [Show full text]
  • Effects of Paraquat and Alachlor on Soil Microorganisms in Peat Soil
    Pertanika 15(2),121-125 (1992) Effects of Paraquat and Alachlor on Soil Microorganisms in Peat Soil ISMAIL SAHID, AINON HAMZAH and PARIDAH M. ARIS Faculty of Life Sciences Universiti Kebangsaan Malaysia 43600 Bangi, Selangor, Malaysia Keywords: AlacWor, paraquat, microbes, peat soil. ABSTRAK Satu kajian telah dijalankan untuk melihat kesan alachlor dan paraquat ke atas aktiviti mikrob dalam tanah gambut. Kesan racun rumpai ke atas pembebasan CO2 dan aktiviti phosphatase dimonitor selama 12 minggu. Hasil yang diperolehi menunjukkan paraquat dan alachlor yang disembur kepada tanah menyebabkan peningkatan pembebasan CO di peringkat awal pengeraman tetapi berkurangan selepas 53 han. Lebih banyak CO dibebaskan 2 2 dari tanah yang dirawat dengan alachlor berbanding dengan tanah yang dirawat dengan paraquat. Aktiviti phosphatase meningkat di peringkat awal pengeraman bagi tanah yang diperlakukan dengan sama ada alachlor atau paraquat. Aktiviti phosphatase meningkat di peringkat awal pengeraman bagi tanah yang diperlakukan dengan sama ada alachlor atau paraquat tetapi aktiviti phosphatase berkurangan seiepas 12 han eraman. Populasi kulat dan bakteria dipengaruhi oleh kedua-dua racun rumpai yang diuji. Pada kepekatan 250 ppm, alachlor dan paraquat, masing-masing menyebabkan pengurangan populasi bakteria kira-kira 78 dan 95%. Alachlor didapati lebih toksik terhadap kulat berbanding paraquat. ABSTRACT A study was carried out to investigate the effects ofalachlor and paraquat on microbial activities in peat soil. Effects ofthe herbicides on CO2 evolution and phosphatase activity were monitored for 12 weeks in ambient conditions. The results showed that paraquat and alachlor caused an initial increase in CO2 released and subsequently decreased after 53 days of incubation. Comparatively, more CO2 was released from the soil treated with alachlor than that treated with paraquat.
    [Show full text]
  • DCMU) Or Paraquat-Treated Euglena Gracilis Cells Erich F
    Chlorophyll Photobleaching and Ethane Production in Dichlorophenyldimethylurea- (DCMU) or Paraquat-Treated Euglena gracilis Cells Erich F. Elstner and W. Osswald Institut für Botanik und Mikrobiologie, Technische Universität München, Arcisstr. 21, D-8000 München 2 Z. Naturforsch. 35 c, 129-135 (1980); received August 20/September 28, 1979 Chlorophyll Bleaching, Herbicides, Euglena gracilis, Ethane, Fat Oxidation Light dependent (35 Klux) chlorophyll bleaching in autotrophically grown Euglena gracilis cells at slightly acidic pH (6.5 —5.4) is stimulated by the photosystem II blockers DCMU and DBMIB (both 10~ 5 m) as well as by the autooxidizable photosystem I electron acceptor, paraquat (1 0 -3 m ). Chlorophyll photobleaching is accompanied by the formation of thiobarbituric acid — sensitive material (“malondialdehyde”) and ethane. Both chlorophyll photobleaching and light dependent ethane formation are partially prevented by higher concentrations (10~* m ) of the autooxidizable photosystem II electron acceptor DBMIB or by sodium bicarbonate (25 mM). In vitro studies with cell free extracts (homogenates) from E. gracilis suggest that a-linolenic acid oxidation by excited (reaction center II) chlorophyll represents the driving force for both ethane formation and chlorophyll bleaching. Ethane formation thus appears to be a sensitive and non-destructive “in vivo’’ marker for both restricted energy dissipation in photosystem II and, conditions yielding reactive oxygen species at the reducing side o f photosystem I. Introduction quent lipid attack and membrane destruction in the case of low potential photosystem I electron ac­ Chlorophyll bleaching is one of the characteristic ceptors as paraquat and other bipyridylium salts symptoms for plant diseases introduced by infec­ [4, 5, 9], tions, certain physical parameters or by chemicals.
    [Show full text]
  • Pesticides EPA-738-F-96-018 Environmental Protection and Toxic Substances August 1997 Agency (7508W) R.E.D
    United States Prevention, Pesticides EPA-738-F-96-018 Environmental Protection And Toxic Substances August 1997 Agency (7508W) R.E.D. FACTS Paraquat Dichloride Pesticide All pesticides sold or distributed in the United States must be Reregistration registered by EPA, based on scientific studies showing that they can be used without posing unreasonable risks to people or the environment. Because of advances in scientific knowledge, the law requires that pesticides which were first registered before November 1, 1984, be reregistered to ensure that they meet today's more stringent standards. Under the Food Quality Protection Act of 1996, EPA must consider the increased susceptibility of infants and children to pesticide residues in food, as well as aggregate exposure of the public to pesticide residues from all sources, and the cumulative effects of pesticides and other compounds with a common mechanism of toxicity in establishing and reassessing tolerances. In evaluating pesticides for reregistration, EPA obtains and reviews a complete set of studies from pesticide producers, describing the human health and environmental effects of each pesticide. The Agency develops any mitigation measures or regulatory controls needed to effectively reduce each pesticide's risks. EPA then reregisters pesticides that can be used without posing unreasonable risks to human health or the environment. When a pesticide is eligible for reregistration, EPA explains the basis for its decision in a Reregistration Eligibility Decision (RED) document. This fact sheet summarizes the information in the RED document for reregistration case 0262, paraquat dichloride (commonly referred to as paraquat). Use Profile Paraquat dichloride is a herbicide currently registered to control weeds and grasses in many agricultural and non-agricultural areas.
    [Show full text]
  • List of Class 1 Designated Chemical Substances
    List of Class 1 Designated Chemical Substances *1：CAS numbers are to be solely as references. They may be insufficient or lacking, in case there are multiple chemical substances. No. Specific Class 1 CAS No. (PRTR Chemical （*1） Name Law) Substances 1 - zinc compounds(water-soluble) 2 79-06-1 acrylamide 3 140-88-5 ethyl acrylate 4 - acrylic acid and its water-soluble salts 5 2439-35-2 2-(dimethylamino)ethyl acrylate 6 818-61-1 2-hydroxyethyl acrylate 7 141-32-2 n-butyl acrylate 8 96-33-3 methyl acrylate 9 107-13-1 acrylonitrile 10 107-02-8 acrolein 11 26628-22-8 sodium azide 12 75-07-0 acetaldehyde 13 75-05-8 acetonitrile 14 75-86-5 acetone cyanohydrin 15 83-32-9 acenaphthene 16 78-67-1 2,2'-azobisisobutyronitrile 17 90-04-0 o-anisidine 18 62-53-3 aniline 19 82-45-1 1-amino-9,10-anthraquinone 20 141-43-5 2-aminoethanol 21 1698-60-8 5-amino-4-chloro-2-phenylpyridazin-3(2H)-one; chloridazon 5-amino-1-[2,6-dichloro-4-(trifluoromethyl)phenyl]-3-cyano- 22 120068-37-3 4[(trifluoromethyl)sulfinyl]pyrazole; fipronil 23 123-30-8 p-aminophenol 24 591-27-5 m-aminophenol 4-amino-6-tert-butyl-3-methylthio-1,2,4-triazin-5(4H)-one; 25 21087-64-9 metribuzin 26 107-11-9 3-amino-1-propene 27 41394-05-2 4-amino-3-methyl-6-phenyl-1,2,4-triazin-5(4H)-one; metamitron 28 107-18-6 allyl alcohol 29 106-92-3 1-allyloxy-2,3-epoxypropane 30 - n-alkylbenzenesulfonic acid and its salts(alkyl C=10-14) 31 - antimony and its compounds 32 120-12-7 anthracene 33 1332-21-4 asbestos ○ 34 4098-71-9 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate 35 78-84-2 isobutyraldehyde
    [Show full text]
  • 20210311 IAEG AD-DSL V5.0 for Pdf.Xlsx
    IAEGTM AD-DSL Release Version 4.1 12-30-2020 Authority: IAEG Identity: AD-DSL Version number: 4.1 Issue Date: 2020-12-30 Key Yellow shading indicates AD-DSL family group entries, which can be expanded to display a non-exhaustive list of secondary CAS numbers belonging to the family group Substance Identification Change Log IAEG Regulatory Date First Parent Group IAEG ID CAS EC Name Synonyms Revision Date ECHA ID Entry Type Criteria Added IAEG ID IAEG000001 1327-53-3 215-481-4 Diarsenic trioxide Arsenic trioxide R1;R2;D1 2015-03-17 2015-03-17 100.014.075 Substance Direct Entry IAEG000002 1303-28-2 215-116-9 Diarsenic pentaoxide Arsenic pentoxide; Arsenic oxide R1;R2;D1 2015-03-17 2015-03-17 100.013.743 Substance Direct Entry IAEG000003 15606-95-8 427-700-2 Triethyl arsenate R1;R2;D1 2015-03-17 2017-08-14 100.102.611 Substance Direct Entry IAEG000004 7778-39-4 231-901-9 Arsenic acid R1;R2;D1 2015-03-17 2015-03-17 100.029.001 Substance Direct Entry IAEG000005 3687-31-8 222-979-5 Trilead diarsenate R1;R2;D1 2015-03-17 2017-08-14 100.020.890 Substance Direct Entry IAEG000006 7778-44-1 231-904-5 Calcium arsenate R1;R2;D1 2015-03-17 2017-08-14 100.029.003 Substance Direct Entry IAEG000009 12006-15-4 234-484-1 Cadmium arsenide Tricadmium diarsenide R1;R2;D1 2017-08-14 2017-08-14 Substance Direct Entry IAEG000021 7440-41-7 231-150-7 Beryllium (Be) R2 2015-03-17 2019-01-24 Substance Direct Entry IAEG000022 1306-19-0 215-146-2 Cadmium oxide R1;R2;D1 2015-03-17 2017-08-14 100.013.770 Substance Direct Entry IAEG000023 10108-64-2 233-296-7 Cadmium
    [Show full text]
  • HPPD) Inhibitor Herbicide Resistance in Waterhemp (Amaranthus Tuberculatus
    University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln U.S. Department of Agriculture: Agricultural Publications from USDA-ARS / UNL Faculty Research Service, Lincoln, Nebraska 5-6-2019 Using RNA-seq to characterize responses to 4 hydroxyphenylpyruvate dioxygenase (HPPD) inhibitor herbicide resistance in waterhemp (Amaranthus tuberculatus) Daniel R. Kohlhase Iowa State University Jamie A. O’Rourke (USDA)–Agricultural Research Service Micheal D. K. Owen Iowa State University, [email protected] Michelle A. Graham (USDA)–Agricultural Research Service, [email protected] Follow this and additional works at: https://digitalcommons.unl.edu/usdaarsfacpub Kohlhase, Daniel R.; O’Rourke, Jamie A.; Owen, Micheal D. K.; and Graham, Michelle A., "Using RNA-seq to characterize responses to 4 hydroxyphenylpyruvate dioxygenase (HPPD) inhibitor herbicide resistance in waterhemp (Amaranthus tuberculatus)" (2019). Publications from USDA-ARS / UNL Faculty. 2163. https://digitalcommons.unl.edu/usdaarsfacpub/2163 This Article is brought to you for free and open access by the U.S. Department of Agriculture: Agricultural Research Service, Lincoln, Nebraska at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in Publications from USDA-ARS / UNL Faculty by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. Kohlhase et al. BMC Plant Biology (2019) 19:182 https://doi.org/10.1186/s12870-019-1795-x RESEARCH ARTICLE Open Access Using RNA-seq to characterize responses to 4-hydroxyphenylpyruvate dioxygenase (HPPD) inhibitor herbicide resistance in waterhemp (Amaranthus tuberculatus) Daniel R. Kohlhase1, Jamie A. O’Rourke2, Micheal D. K. Owen1* and Michelle A. Graham2* Abstract Background: Waterhemp (Amaranthus tuberculatus (Moq.) J.D. Sauer) is a problem weed commonly found in the Midwestern United States that can cause crippling yield losses for both maize (Zea mays L.) and soybean (Glycine max L.
    [Show full text]