WorldWideScience

Sample records for chlorophyll

  1. Chlorophylls - natural solar cells

    CERN Document Server

    Jantschi, Lorentz; Balan, Mugur C; Sestras, Radu E

    2011-01-01

    A molecular modeling study was conducted on a series of six natural occurring chlorophylls. Quantum chemistry calculated orbital energies were used to estimate frequency of transitions between occupied molecular orbital and unoccupied molecular orbital energy levels of chlorophyll molecules in vivo conditions in standard (ASTMG173) environmental conditions. Obtained results are in good agreement with energies necessary to fix the Magnesium atom by chlorophyll molecules and with occurrence of chlorophylls in living vegetal organisms.

  2. Chlorophyll and starch assays

    OpenAIRE

    sprotocols

    2015-01-01

    Chlorophyll, starch, and sugar contents are good indicators of growth vigor in plants. To measure the chlorophyll content, we used a modified protocol (1,2). The starch content was determined using iodine staining (3) and enzymatic reactions (4-6).

  3. Chlorophyll Degradation in Horticultural Crops

    OpenAIRE

    Kaewsuksaeng, Samak

    2011-01-01

    One of the symptoms of senescence in harvested horticultural crops is the loss of greenness that comes with the degradation of chlorophyll. With senescence, the chlorophyll-degrading enzyme activities such as chlorophyllase, Mg-dechelatase or Mg-dechelation activity, a new chlorophyll-degrading enzyme, pheophytinase, pheophorbidase and chlorophyll-degrading peroxidase, which are involved in chlorophyll degradation, affected greatly in stored horticultural crops. The chlorophyll derivatives, e...

  4. Chlorophyll_Master

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set included chlorophyll for each subregion in the study (Georges Bank, Gulf of Maine, Southern New England, Middle Atlantic Bight) . The data came from...

  5. OSU Chlorophyll Bloom Product

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This product was developed for the Oregon coast based on the observed change between running 8-day composite chlorophyll-a (CHL) data obtained by the MODerate...

  6. Chlorophyll: The wonder pigment

    Digital Repository Service at National Institute of Oceanography (India)

    Bhat, S.R.

    juice or grow our own sprouts, instead we try to get the benefits of green foods through capsules, tablets or powder of dehydrated or freeze dried forms of wheat grass, blue green algae, or different cereal grasses. Chlorophyll or its derivative... vegetables rich in micronutrients are spinach, drum stick leaves, lettuce, cucumber, beans and green peas. SCIENCE REPORTER, July 2005 31 Feature Article Chlorophyll in Algae Amazingly, some freshwater and marine algae, yet to find place in our daily diet...

  7. Optofluidic chlorophyll lasers.

    Science.gov (United States)

    Chen, Yu-Cheng; Chen, Qiushu; Fan, Xudong

    2016-06-21

    Chlorophylls are essential for photosynthesis and also one of the most abundant pigments on earth. Using an optofluidic ring resonator of extremely high Q-factors (>10(7)), we investigated the unique characteristics and underlying mechanism of chlorophyll lasers. Chlorophyll lasers with dual lasing bands at 680 nm and 730 nm were observed for the first time in isolated chlorophyll a (Chla). Particularly, a laser at the 730 nm band was realized in 0.1 mM Chla with a lasing threshold of only 8 μJ mm(-2). Additionally, we observed lasing competition between the two lasing bands. The presence of laser emission at the 680 nm band can lead to quenching or significant reduction of laser emission at the 730 nm band, effectively increasing the lasing threshold for the 730 nm band. Further concentration-dependent studies, along with theoretical analysis, elucidated the mechanism that determines when and why the laser emission band appears at one of the two bands, or concomitantly at both bands. Finally, Chla was exploited as the donor in fluorescence resonance energy transfer to extend the laser emission to the near infrared regime with an unprecedented wavelength shift as large as 380 nm. Our work will open a door to the development of novel biocompatible and biodegradable chlorophyll-based lasers for various applications such as miniaturized tunable coherent light sources and in vitro/in vivo biosensing. It will also provide important insight into the chlorophyll fluorescence and photosynthesis processes inside plants. PMID:27220992

  8. Pulse amplitude modulated chlorophyll fluorometer

    Energy Technology Data Exchange (ETDEWEB)

    Greenbaum, Elias; Wu, Jie

    2015-12-29

    Chlorophyll fluorometry may be used for detecting toxins in a sample because of changes in micro algae. A portable lab on a chip ("LOAC") based chlorophyll fluorometer may be used for toxin detection and environmental monitoring. In particular, the system may include a microfluidic pulse amplitude modulated ("PAM") chlorophyll fluorometer. The LOAC PAM chlorophyll fluorometer may analyze microalgae and cyanobacteria that grow naturally in source drinking water.

  9. As clorofilas The chlorophylls

    Directory of Open Access Journals (Sweden)

    Nivia Maria Streit

    2005-06-01

    Full Text Available As clorofilas são pigmentos verdes, comuns em todas as células fotossintéticas. Por sua estrutura química ser instável, são facilmente degradadas, resultando em produtos de decomposição que modificam a percepção e qualidade dos alimentos. Esta revisão trata dos vários fatores que interferem na degradação das clorofilas, como a luz, radiação, calor, ácidos, oxigênio, alteração enzimática e interação com outros pigmentos. Também, outro aspecto a ser abordado é a utilização das clorofilas como corantes, através da formação de complexos que tornam esses pigmentos mais estáveis à decomposição.The Chlorophylls are a common green pigment to all photosynthetic cells. They are easily degraded, because of their unstable chemical structure. Degradation results in products alter the perception and quality of foods. This review discusses the various factors, that interfere on chlorophyll degradation such as light, irradiation, heat, acids, oxygen, enzymatical alteration and the interaction with other pigments. Also, the other topic that was mentioned the utilization of the chlorophylls as dyes through a complex formation that make this pigment more stable to degradation.

  10. Chlorophyll a + b content and chlorophyll fluorescence in avocado

    Science.gov (United States)

    One Tonnage (T) and one Simmonds (S) avocado tree and four TxS crosses were evaluated for differences in chlorophyll content and maximal quantum yield of photosystem II in sun and shade-type leaves. Total chlorophyll content by area (Chl a+bar) ranged from 981 mg m-2 in TxS240 to 4339 mg m-2 in Simm...

  11. Chlorophyll d: the puzzle resolved

    DEFF Research Database (Denmark)

    Larkum, Anthony W D; Kühl, Michael

    2005-01-01

    Chlorophyll a (Chl a) has always been regarded as the sole chlorophyll with a role in photochemical conversion in oxygen-evolving phototrophs, whereas chlorophyll d (Chl d), discovered in small quantities in red algae in 1943, was often regarded as an artefact of isolation. Now, as a result of...... discoveries over the past year, it has become clear that Chl d is the major chlorophyll of a free-living and widely distributed cyanobacterium that lives in light environments depleted in visible light and enhanced in infrared radiation. Moreover, Chl d not only has a light-harvesting role but might also...... replace Chl a in the special pair of chlorophylls in both reactions centers of photosynthesis. Udgivelsesdato: 2005-Aug...

  12. Chlorophylls, Symmetry, Chirality, and Photosynthesis

    Directory of Open Access Journals (Sweden)

    Mathias O. Senge

    2014-09-01

    Full Text Available Chlorophylls are a fundamental class of tetrapyrroles and function as the central reaction center, accessory and photoprotective pigments in photosynthesis. Their unique individual photochemical properties are a consequence of the tetrapyrrole macrocycle, the structural chemistry and coordination behavior of the phytochlorin system, and specific substituent pattern. They achieve their full potential in solar energy conversion by working in concert in highly complex, supramolecular structures such as the reaction centers and light-harvesting complexes of photobiology. The biochemical function of these structures depends on the controlled interplay of structural and functional principles of the apoprotein and pigment cofactors. Chlorophylls and bacteriochlorophylls are optically active molecules with several chiral centers, which are necessary for their natural biological function and the assembly of their supramolecular complexes. However, in many cases the exact role of chromophore stereochemistry in the biological context is unknown. This review gives an overview of chlorophyll research in terms of basic function, biosynthesis and their functional and structural role in photosynthesis. It highlights aspects of chirality and symmetry of chlorophylls to elicit further interest in their role in nature.

  13. Chlorophylls, Symmetry, Chirality, and Photosynthesis.

    OpenAIRE

    Mathias O. Senge; Aoife A. Ryan; Kristie A. Letchford; Stuart A. MacGowan; Tamara Mielke

    2014-01-01

    Chlorophylls are a fundamental class of tetrapyrroles and function as the central reaction center, accessory and photoprotective pigments in photosynthesis. Their unique individual photochemical properties are a consequence of the tetrapyrrole macrocycle, the structural chemistry and coordination behavior of the phytochlorin system, and specific substituent pattern. They achieve their full potential in solar energy conversion by working in concert in highly complex, supramolecular structures ...

  14. Efficient Chlorophyll Fluorescence Measurements of Sugarcane

    Science.gov (United States)

    As with many crops, chlorophyll fluorescence emission is a promising tool for measuring responses of sugarcane (Saccharum spp.) to biotic and abiotic stresses. Chlorophyll fluorescence can be easily measured using portable fluorometers. However, several factors should be considered in order to op...

  15. Seasonal Composite Chlorophyll Concentrations - Gulf of Maine

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This personal geodatabase contains raster images of chlorophyll concentrations in the Gulf of Maine. These raster images are seasonal composites, and were...

  16. Monolayers and multilayers of chlorophyll [correction of chlorophyl] a on a mercury electrode.

    Science.gov (United States)

    Moncelli, M R; Becucci, L; Dolfi, A; Tadini Buoninsegni, F; Agostiano, A

    2002-05-15

    A novel experimental technique used to investigate chlorophyll films on a hanging mercury drop electrode is described. Two different procedures are employed to prepare self-assembled chlorophyll monolayers and multilayers on the mercury electrode. Upon illuminating the chlorophyll a (Chl)-coated mercury electrode with an appropriate light source, the photocurrents generated by the Chl aggregates are measured under short-circuit conditions in the absence of photoartefacts. The preliminary results obtained by this novel technique are presented. PMID:12009465

  17. Induction of chlorophyll chimeras and chlorophyll mutations in mungbean (Vigna radiata) cv. T44

    International Nuclear Information System (INIS)

    Uniform and healthy seeds of mungbean (Vigna radiata) cv. T44 were exposed to varying doses of gamma rays, ethyl methane sulphonate (EMS) and combination treatment of gamma rays with EMS. The data were recorded for seed germination, plant survival, frequency and spectrum of chlorophyll chimeras in M1 and chlorophyll mutations in M2 generation. Among all, the combination treatments were found most effective for inducing chlorophyll chimeras and chlorophyll mutations than the gamma rays or EMS alone. Of the mutants under reference, the albino, xantha and chlorina showed monogenic recessive while viridis exhibited digenic recessive inheritance. (author). 8 refs., 2 tabs

  18. QTL Mapping of Chlorophyll Contents in Rice

    Institute of Scientific and Technical Information of China (English)

    SHEN Bo; ZHUANG Jie-yun; ZHANG Ke-qin; DAI Wei-min; LU Ye; FU Li-qing; DING Jia-ming; ZHENG Kang-le

    2007-01-01

    The objectives of this study were to investigate the genetic factors controlling the chlorophyll content of rice leaf using QTL analysis. A linkage map consisting of 207 DNA markers was constructed by using 247 recombinant inbred lines (RILs) derived from an indica-indica rice cross of Zhenshan97B×Milyang 46. In 2002 and 2003, the contents of chlorophyll a and b of the parents and the 247 RILs were measured on the top first leaf, top second leaf, and top third leaf, respectively. The software QTLMapper 1.6 was used to detect quantitative trait loci (QTLs), additive by environment (AE) interactions, and epistatic by environment (AAE) interactions. A total of eight QTLs in four intervals were detected to have significant additive effects on chlorophyll a and b contents at different leaf positions, with 1.96-9.77% of phenotypic variation explained by a single QTL, and two QTLs with significant AE interactions were detected. Epistasis analysis detected nine significant additive-by-additive interactions on chlorophyll a and b contents, and one pair of QTLs with significant AAE interactions was detected. On comparison with QTLs for yield traits detected in the same population, it was found in many cases that the QTLs for chlorophyll a and b contents and those for yield traits were located in the same chromosome intervals.

  19. Bowel perforation detection using metabolic fluorescent chlorophylls

    Science.gov (United States)

    Han, Jung Hyun; Jo, Young Goun; Kim, Jung Chul; Choi, Sujeong; Kang, Hoonsoo; Kim, Yong-Chul; Hwang, In-Wook

    2016-03-01

    Thus far, there have been tries of detection of disease using fluorescent materials. We introduce the chlorophyll derivatives from food plants, which have longer-wavelength emissions (at >650 nm) than those of fluorescence of tissues and organs, for detection of bowel perforation. To figure out the possibility of fluorescence spectroscopy as a monitoring sensor of bowel perforation, fluorescence from organs of rodent models, intestinal and peritoneal fluids of rodent models and human were analyzed. In IVIS fluorescence image of rodent abdominal organ, visualization of perforated area only was possible when threshold of image is extremely finely controlled. Generally, both perforated area of bowel and normal bowel which filled with large amount of chlorophyll derivatives were visualized with fluorescence. The fluorescence from chlorophyll derivatives penetrated through the normal bowel wall makes difficult to distinguish perforation area from normal bowel with direct visualization of fluorescence. However, intestinal fluids containing chlorophyll derivatives from food contents can leak from perforation sites in situation of bowel perforation. It may show brighter and longer-wavelength regime emissions of chlorophyll derivatives than those of pure peritoneal fluid or bioorgans. Peritoneal fluid mixed with intestinal fluids show much brighter emissions in longer wavelength (at>650 nm) than those of pure peritoneal fluid. In addition, irrigation fluid, which is used for the cleansing of organ and peritoneal cavity, made of mixed intestinal and peritoneal fluid diluted with physiologic saline also can be monitored bowel perforation during surgery.

  20. The spontaneous chlorophyll mutation frequency in barley

    DEFF Research Database (Denmark)

    Jørgensen, Jørgen Helms; Jensen, Hans Peter

    1986-01-01

    A total of 1866 barley plants were progeny tested in the greenhouse. Twenty-five plants segregated for newly arisen, spontaneous chlorophyll mutant genes. Among the total of 470,129 seedlings screened there were 79 mutants (1.7 .+-. 0.6 .times. 10-4). The data are added to data from three similar...... materials and the resulting estimate of the chlorophyll mutant frequency is 1.6 .times. 10-4 in about 1.43 million seedlings. The estimate of the chlorophyll mutation rate per generation is close to 67.3 .times. 10-4 per diploid genome or in the order of 6 .times. 10-7 per locus and haploid genome....

  1. Localisation of chlorophyll within the chloroplast

    NARCIS (Netherlands)

    Thomas, J.B.; Post, L.C.; Vertregt, N.

    1954-01-01

    Silver nitrate reduction was shown to occur in illuminated suspensions of Hibiscus grana. The action spectrum of this reduction, the reaction, proved to coincide satisfactorily with the chlorophyll absorption spectrum. Electron micrographs reveal that this reaction occurs in single lamellae. From

  2. Thin Layer Chromatography (TLC) of Chlorophyll Pigments.

    Science.gov (United States)

    Foote, Jerry

    1984-01-01

    Background information, list of materials needed, procedures used, and discussion of typical results are provided for an experiment on the thin layer chromatography of chlorophyll pigments. The experiment works well in high school, since the chemicals used are the same as those used in paper chromatography of plant pigments. (JN)

  3. Phytoplankton productivity quantified from chlorophyll fluorescence

    DEFF Research Database (Denmark)

    Hancke, Kasper; Dalsgaard, Tage; Sejr, Mikael Kristian;

    Phytoplankton are the main food source for marine life, and accurate uantification of its productivity is essential for understanding how marine food webs function. As a novel non-invasive technology, chlorophyll fluorescence can be used to assess in situ primary production in phytoplankton...

  4. MANUFACTURE OF PHOTOVOLTAIC SOLAR CELL USING PLANT CHLOROPHYLL

    Science.gov (United States)

    To date, we have successfully manufactured working chlorophyll sensitized solar cells using chlorophyll (and b mixture) from spinach leaves. We have evaluated the electronic characteristics (voltage, current, and power outputs using different loading resistors) of this solar c...

  5. Chlorophyll in tomato seeds: marker for seed performance?

    OpenAIRE

    Suhartanto, M.R.

    2002-01-01

    Using Xe-PAM, laser induced fluorometry and high performance liquid chromatography we found that chlorophyll was present in young tomato (cv. Moneymaker) seeds and was degraded during maturation. Fluorescence microscopy and imaging showed that the majority of chlorophyll is located in the seed coat but low levels of chlorophyll were also detected in the embryo, mainly in the radicle tip. Seed chlorophyll fluorescence appeared to be a sensitive indicator of physiological maturity of tomato see...

  6. Bleaching of chlorophylls by UV irradiation in vitro: the effects on chlorophyll organization in acetone and n-hexane

    OpenAIRE

    JELENA ZVEZDANOVIC; DEJAN MARKOVIC

    2008-01-01

    The stability of chlorophylls toward UV irradiation was studied by Vis spectrophotometry in extracts containing mixtures of photosynthetic pigments in acetone and n-hexane. The chlorophylls underwent destruction (bleaching) obeying first-order kinetics. The bleaching was governed by three major factors: the energy input of the UV photons, the concentration of the chlorophylls and the polarity of the solvent, implying different molecular organizations of the chlorophylls in the two solvents.

  7. Fractal structures in casting films from chlorophyll

    Science.gov (United States)

    Pedro, G. C.; Gorza, F. D. S.; de Souza, N. C.; Silva, J. R.

    2014-04-01

    Chlorophyll (Chl) molecules are important because they can act as natural light-harvesting devices during the photosynthesis. In addition, they have potential for application as component of solar cell. In this work, we have prepared casting films from chlorophyll (Chl) and demonstrated the occurrence of fractal structures when the films were submitted to different concentrations. By using optical microscopy and the box-count method, we have found that the fractal dimension is Df = 1.55. This value is close to predicted by the diffusion-limited aggregation (DLA) model. This suggests that the major mechanism - which determines the growth of the fractal structures from Chl molecules - is the molecular diffusion. Since the efficiencies of solar cells depend on the morphology of their interfaces, these finds can be useful to improve this kind of device.

  8. Genetic analysis of sunflower chlorophyll mutants

    International Nuclear Information System (INIS)

    The method of getting the chlorophyll mutations in sunflower was developed by Y.D. Beletskii in 1969 with the use of N-nitroso-N-methylurea (NMH). Certain concentrations of NMH are known to induce plastid mutations in growing seeds, and their yield depends on the duration of the exposure. The given work presented studies on the influence of rifampicin (R) and 2,4-dinitrophenol (DNP) on the genetic activity NMH, as an inductor of plastid and nuclear mutations

  9. Extraction of Chlorophyll from Alfalfa Plant

    OpenAIRE

    Ali Khalid Khudair Al-Jomaily; Ahmed Jawad; Isam Kamal

    2006-01-01

    The extraction process of chlorophyll from dehydrated and pulverized alfalfa plant were studied by percolation method. Two solvent systems were used for the extraction namely; Ethanol-water and Hexane-Toluene systems . The effect of circulation rate, solvent concentration, and solvent volume to solid weight ratio were studied. In both ethanol water, and Hexane-Toluene systems it appears that solvent concentration is the most effective variable.

  10. Extraction of Chlorophyll from Alfalfa Plant

    Directory of Open Access Journals (Sweden)

    Ali Khalid Khudair Al-Jomaily

    2006-01-01

    Full Text Available The extraction process of chlorophyll from dehydrated and pulverized alfalfa plant were studied by percolation method. Two solvent systems were used for the extraction namely; Ethanol-water and Hexane-Toluene systems . The effect of circulation rate, solvent concentration, and solvent volume to solid weight ratio were studied. In both ethanol water, and Hexane-Toluene systems it appears that solvent concentration is the most effective variable.

  11. Chlorophyll fluorescence emission spectrum inside a leaf

    OpenAIRE

    Pedrós Esteban, Roberto; Moya, Ismael; Goulas, Yves; Jacquemoud, Stéphane

    2008-01-01

    Chlorophyll a fluorescence can be used as an early stress indicator. Fluorescence is also connected to photosynthesis so it can be proposed for global monitoring of vegetation status from a satellite platform. Nevertheless, the correct interpretation of fluorescence requires accurate physical models. The spectral shape of the leaf fluorescence free of any re-absorption effect plays a key role in the models and is difficult to measure. We present a vegetation fluorescence emission spectrum fre...

  12. Degradation of Chlorophyll Luminescence in Plants

    International Nuclear Information System (INIS)

    The chlorophyll photoluminescence intensity degradation of Vallisneria spiralis L. water plant is studied. It is shown that the degradation curve is rather well described by a sum of two hyperbolic functions. The rate of intensity degradation reduces at low temperatures. At room temperature, a slow restoration of the luminescent system is observed after the irradiation has been ceased. No restoration is detected at the liquid nitrogen temperature. A simplified model which describes the luminescence degradation according to the quadratic law is suggested.

  13. Chlorophyll loss associated with heat-induced senescence in bentgrass.

    Science.gov (United States)

    Jespersen, David; Zhang, Jing; Huang, Bingru

    2016-08-01

    Heat stress-induced leaf senescence is characterized by the loss of chlorophyll from leaf tissues. The objectives of this study were to examine genetic variations in the level of heat-induced leaf senescence in hybrids of colonial (Agrostis capillaris)×creeping bentgrass (Agrostis stolonifera) contrasting in heat tolerance, and determine whether loss of leaf chlorophyll during heat-induced leaf senescence was due to suppressed chlorophyll synthesis and/or accelerated chlorophyll degradation in the cool-season perennial grass species. Plants of two hybrid backcross genotypes ('ColxCB169' and 'ColxCB190') were exposed to heat stress (38/33°C, day/night) for 28 d in growth chambers. The analysis of turf quality, membrane stability, photochemical efficiency, and chlorophyll content demonstrated significant variations in the level of leaf senescence induced by heat stress between the two genotypes, with ColXCB169 exhibiting a lesser degree of decline in chlorophyll content, photochemical efficiency and membrane stability than ColXCB190. The assays of enzymatic activity or gene expression of several major chlorophyll-synthesizing (porphobilinogen deaminase, Mg-chelatase, protochlorophyllide-reductase) and chlorophyll-degrading enzymes (chlorophyllase, pheophytinase, and chlorophyll-degrading peroxidase) indicated heat-induced decline in leaf chlorophyll content was mainly due to accelerated chlorophyll degradation, as manifested by increased gene expression levels of chlorophyllase and pheophytinase, and the activity of pheophytinase (PPH), while chlorophyll-synthesizing genes and enzymatic activities were not differentially altered by heat stress in the two genotypes. The analysis of heat-induced leaf senescence of pph mutants of Arabidopsis further confirmed that PPH could be one enzymes that plays key roles in regulating heat-accelerated chlorophyll degradation. Further research on enzymes responsible in part for the loss of chlorophyll during heat

  14. Evaluating the relationship between leaf chlorophyll concentration and SPAD-502 chlorophyll meter readings.

    Science.gov (United States)

    Uddling, J; Gelang-Alfredsson, J; Piikki, K; Pleijel, H

    2007-01-01

    Relationships between chlorophyll concentration ([chl]) and SPAD values were determined for birch, wheat, and potato. For all three species, the relationships were non-linear with an increasing slope with increasing SPAD. The relationships for birch and wheat were strong (r (2) approximately 0.9), while the potato relationship was comparatively weak (r (2) approximately 0.5). Birch and wheat had very similar relationships when the chlorophyll concentration was expressed per unit leaf area, but diverged when it was expressed per unit fresh weight. Furthermore, wheat showed similar SPAD-[chl] relationships for two different cultivars and during two different growing seasons. The curvilinear shape of the SPAD-[chl] relationships agreed well with the simulated effects of non-uniform chlorophyll distribution across the leaf surface and multiple scattering, causing deviations from linearity in the high and low SPAD range, respectively. The effect of non-uniformly distributed chlorophyll is likely to be more important in explaining the non-linearity in the empirical relationships, since the effect of scattering was predicted to be comparatively weak. The simulations were based on the algorithm for the calculation of SPAD-502 output values. We suggest that SPAD calibration curves should generally be parameterised as non-linear equations, and we hope that the relationships between [chl] and SPAD and the simulations of the present study can facilitate the interpretation of chlorophyll meter calibrations in relation to optical properties of leaves in future studies. PMID:17342446

  15. Salt stress change chlorophyll fluorescence in mango

    Directory of Open Access Journals (Sweden)

    Cicero Cartaxo de Lucena

    2012-12-01

    Full Text Available This study evaluated the tolerance of mango cultivars 'Haden', 'Palmer', 'Tommy Atkins' and 'Uba' grafted on rootstock 'Imbú' to salt stress using chlorophyll fluorescence. Plants were grown in modified Hoagland solution containing 0, 15, 30, and 45 mmol L-1 NaCl. At 97 days the parameters of the chlorophyll fluorescence (F0, Fm, Fv, F0/Fm, Fv/Fm, Fv'/Fm', ΦPSII = [(Fm'-Fs/(Fm'], D = (1- Fv'/Fm' and ETR = (ΦPSII×PPF×0,84×0,5 were determined. At 100 days, the leaf emission and leaf area, toxicity and leaf abscission indexes were determined. In all cultivars evaluated, in different degree, there were decreases in photochemical efficiency of photosystem II, enhanced concentrations from 15 mmol L-1 NaCl. The decreases in the potential quantum yield of photosystem II (Fv/Fm were 27.9, 18.7, 20.5, and 27.4%, for cultivars 'Haden', 'Palmer', 'Tommy Atkins', and 'Uba', respectively, when grown in 45 mmol L-1 NaCl. It was found decreases in leaf emission and mean leaf area in all cultivars from 15 mmol L-1 NaCl. There were increases in leaf toxicity of 33.0, 67.5, 41.6 and 80.8% and in leaf abscission of 71.8, 29.2, 32.5, and 67.9% for the cultivars 'Haden', 'Palmer', 'Tommy Atkins', and 'Uba' respectively, when grown in 45 mmol L-1 NaCl. Leaf toxicity and leaf abscission were not observed in 15 mmol L-1 NaCl. The decrease in Fv/Fm ratio were accompanied by decreasing in leaf emission and increased leaf toxicity index, showing, therefore, the potential of chlorophyll fluorescence in the early detection of salt stress in mango tree.

  16. The Magnesium Chelation Step in Chlorophyll Biosynthesis

    Energy Technology Data Exchange (ETDEWEB)

    Gregory L. Dilworth, Ph.D Chemical Sciences, Geosciences and Biosciences Division Office of Basis Energy Sciences, greg.dilworth@science.doe.gov

    2001-01-17

    The progress described in this report encompasses work supported by DOE grant DE-FG09-89ER13989 for the period 2/15/92 to the present 6/14/94. The goals of the project were to continue investigating the enzymology of Mg-chelatase and to investigate the co-regulation of heme and chlorophyll formation in intact plastids. During this period the laboratory had additional support (two years) from USDA to investigate heme metabolism in chloroplasts. This report is arranged so that the progress is described by reference to manuscripts which are published, under review or in preparation.

  17. Photo-bleaching response in chlorophyll solutions

    International Nuclear Information System (INIS)

    Photo-excitation processes were investigated in chlorophyll solutions by irradiation with UV light sources. Photo-excited bulk effects during the bleaching experiments were diagnosed. The optical diagnostic was expressed by a Beer-Lambert matrix formulation and applied to the experimental results. The chromophores evaluated optical cross-section was 10-15 cm2 and the optical absorption coefficient dynamic variation was fitted to a simple reaction rate model. The bleaching rates were expressed by this model and fitted to the experimental data

  18. Isolation of chlorophylls from stinging nettle (Urtica dioica L.)

    OpenAIRE

    Hojnik, Maša; Škerget, Mojca; Knez, Željko

    2012-01-01

    This study was aimed to assess the feasibility of extracting chlorophylls fromstinging nettle (Urtica dioica L.) by solvent extraction. In preliminary, the investigation concerned three parts of raw material (leaves, stalk and whole plant), different preservation techniques (blanching and drying) and different storage temperatures of preserved material ( |20 C for blanched and 4 C for dried sample). Extracts were analysed for chlorophyll A and chlorophyll B, respectively, by means of HPLC met...

  19. In vitro complexes of copper and zinc with chlorophyll

    OpenAIRE

    JELENA PETROVIC; GORAN NIKOLIC; DEJAN MARKOVIC

    2006-01-01

    Complexes of copper and zinc with chlorophyll, the major photosynthesis pigment, were studied by Vis, FTIR and fluorescence spectroscopy. Two types of complexes were recognized. While copper replaces the central magnesium atom of chlorophyll to form a “central” Cu–Chl complex, this was not proposed in the case of zinc. Instead, the zinc-mediated formation of a 6-membered chelate cycle fused at the periphery of the chlorophyll structure is proposed. The latter event could be ascribed to allome...

  20. Surface disturbance of cryptobiotic soil crusts: nitrogenase activity, chlorophyll content, and chlorophyll degradation

    Science.gov (United States)

    Belnap, Jayne; Harper, Kimball T.; Warren, Steven D.

    1994-01-01

    Cryptobiotic soil crusts are an important component of semiarid and arid ecosystems. An important role of these crusts is the contribution of fixed nitrogen to cold‐desert ecosystems. This study examines the residual effects of various intensities and combinations of different surface disturbances (raking, scalping, and tracked vehicles) on nitrogenase activity, chlorophyll content, and chlorophyll degradation in these soil crusts. Nine months after disturbance chlorophyll content of disturbed soils was not statistically different from undisturbed controls, except in the scalped treatments, indicating recovery of this characteristic is fairly quick unless surface material is removed. Differences in chlorophyll degradation among treatments were not statistically significant. However, nitrogenase activity in all treatments showed tremendous reductions, ranging from 77–97%, when compared to the control, indicating this characteristic is slow to recover. Consequently, assessment of crustal recovery from disturbance must include not only visual and biomass characteristics but other physiological measurements as well. Areas dominated by these crusts should be managed conservatively until the implications of crustal disturbance is better understood.

  1. Remote sensing of terrestrial chlorophyll fluorescence from space

    OpenAIRE

    Frankenberg, Christian; Berry, Joseph; Guanter, Luis; JOINER Joanna

    2013-01-01

    High-resolution spectrometers enable new avenues in global carbon cycle research, including the first accurate retrievals of chlorophyll fluorescence from space as an indicator of photosynthetic activity.

  2. [Estimation of canopy chlorophyll content using hyperspectral data].

    Science.gov (United States)

    Dong, Jing-Jing; Wang, Li; Niu, Zheng

    2009-11-01

    Many researches have developed models to estimate chlorophyl content at leaf and canopy level, but they were species-specific. The objective of the present paper was to develop a new model. First, canopy reflectance was simulated for different species and different canopy architecture using radiative transfer models. Based on the simulated canopy reflectance, the relationship between canopy reflectance and canopy chlorophyll content was studied, and then a chlorophyll estimation model was built using the method of spectral index. The coefficient of determination (R2) between spectral index based model and canopy chlorophyll content reached 0.75 for simulated data. To investigate the applicability of this chlorophyll model, the authors chose a field sample area in Gansu Province to carry out the measurement of leaf chlorophyll content, canopy reflectance and other parameters. Besides, the authors also ordered the synchronous Hyperion data, a hyperspectral image with a spatial resolution of 30 m. Canopy reflectance from field measurment and reflectance from Hyperion image were respectively used as the input parameter for the chlorophyll estimation model. Both of them got good results, which indicated that the model could be used for accurate canopy chlorophyll estimation using canopy reflectance. However, while using spaceborne hyperspectral data to estimate canopy chlorophyll content, good atmospheric correction is required. PMID:20101973

  3. The magnesium chelation step in chlorophyll biosynthesis

    Energy Technology Data Exchange (ETDEWEB)

    Weinstein, J.D.

    1991-01-01

    The biogenesis of energy transducing membranes requires the coordinate synthesis of prosthetic groups, proteins and lipids. Two of the major prosthetic groups, chlorophyll and heme, share a common biosynthetic pathway that diverges at the point of metal insertion into protoporphyrin IX. Insertion of iron leads to heme, while insertion of magnesium leads to chlorophyll. The Mg-chelatase from intact cucumber chloroplasts has been characterized with regard to substrate specificity, regulation, ATP requirement, and a requirement for intact chloroplasts. Mg-chelatase was isolated from maize, barley and peas and characterized in order to circumvent the intact chloroplast requirement of cucumber Mg-chelatase. Pea Mg-chelatase activity is higher than cucumber Mg-chelatase activity, and lacks the requirement for intact chloroplasts. Studies on isolated pea Mg-chelatase have shown more cofactors are required for the reaction than are seen with ferrochelatase, indicating a greater opportunity for regulatory control of this pathway. Two of the cofactors are proteins, and there appears to be a requirement for a protease-sensitive component which is outside the outer envelope. We are developing a continuous spectrophotometric assay for Mg-chelatase activity, and an assay for free heme which has shown heme efflux from intact chloroplasts. 18 refs. (MHB)

  4. The role of chlorophyll b in photosynthesis: Hypothesis

    Directory of Open Access Journals (Sweden)

    Park Hyoungshin

    2001-10-01

    Full Text Available Abstract Background The physico-chemical properties of chlorophylls b and c have been known for decades. Yet the mechanisms by which these secondary chlorophylls support assembly and accumulation of light-harvesting complexes in vivo have not been resolved. Presentation Biosynthetic modifications that introduce electronegative groups on the periphery of the chlorophyll molecule withdraw electrons from the pyrrole nitrogens and thus reduce their basicity. Consequently, the tendency of the central Mg to form coordination bonds with electron pairs in exogenous ligands, a reflection of its Lewis acid properties, is increased. Our hypothesis states that the stronger coordination bonds between the Mg atom in chlorophyll b and chlorophyll c and amino acid sidechain ligands in chlorophyll a/b- and a/c-binding apoproteins, respectively, enhance their import into the chloroplast and assembly of light-harvesting complexes. Testing Several apoproteins of light-harvesting complexes, in particular, the major protein Lhcb1, are not detectable in leaves of chlorophyll b-less plants. A direct test of the hypothesis – with positive selection – is expression, in mutant plants that synthesize only chlorophyll a, of forms of Lhcb1 in which weak ligands are replaced with stronger Lewis bases. Implications The mechanistic explanation for the effects of deficiencies in chlorophyll b or c points to the need for further research on manipulation of coordination bonds between these chlorophylls and chlorophyll-binding proteins. Understanding these interactions will possibly lead to engineering plants to expand their light-harvesting antenna and ultimately their productivity.

  5. An Integrated Protein Chemistry Laboratory: Chlorophyll and Chlorophyllase

    Science.gov (United States)

    Arkus, Kiani A. J.; Jez, Joseph M.

    2008-01-01

    Chlorophyll, the most abundant pigment in nature, is degraded during normal plant growth, when leaves change color, and at specific developmental stages. Chlorophyllase catalyzes the first chemical reaction in this process, that is, the hydrolysis of chlorophyll into chlorophyllide. Here, we describe a series of laboratory sessions designed to…

  6. Modulated Chlorophyll "a" Fluorescence: A Tool for Teaching Photosynthesis

    Science.gov (United States)

    Marques da Silva, Jorge; Bernardes da Silva, Anabela; Padua, Mario

    2007-01-01

    "In vivo" chlorophyll "a" fluorescence is a key technique in photosynthesis research. The recent release of a low cost, commercial, modulated fluorometer enables this powerful technology to be used in education. Modulated chlorophyll a fluorescence measurement "in vivo" is here proposed as a tool to demonstrate basic photosynthesis phenomena to…

  7. Investigating the control of chlorophyll degradation by genomic correlation mining

    Science.gov (United States)

    Chlorophyll degradation is an intricate process that is critical in a variety of plant tissues at different times during the plant life cycle. Many of the photoactive chlorophyll degradation intermediates are exceptionally cytotoxic necessitating that the pathway be carefully coordinated and regulat...

  8. A model for chlorophyll fluorescence and photosynthesis at leaf scale

    NARCIS (Netherlands)

    Tol, van der C.; Verhoef, W.; Rosema, A.

    2009-01-01

    This paper presents a leaf biochemical model for steady-state chlorophyll fluorescence and photosynthesis of C3 and C4 vegetation. The model is a tool to study the relationship between passively measured steady-state chlorophyll fluorescence and actual photosynthesis, and its evolution during the da

  9. Chlorophyll in tomato seeds: marker for seed performance?

    NARCIS (Netherlands)

    Suhartanto, M.R.

    2002-01-01

    Using Xe-PAM, laser induced fluorometry and high performance liquid chromatography we found that chlorophyll was present in young tomato (cv. Moneymaker) seeds and was degraded during maturation. Fluorescence microscopy and imaging showed that the majority of chlorophyll is located in the seed coat

  10. Influence of selected abiotic factors on the decomposition of chlorophylls

    Directory of Open Access Journals (Sweden)

    Gra¿yna Kowalewska

    2001-09-01

    Full Text Available The paper presents the results of experiments to determine the influence of selected physico-chemical factors - oxygen, visible light and temperature - on the decomposition of (1 chlorophylls a, b and c, chlorophyll a derivatives and beta-carotene in acetone solution, and (2 chlorophyll a and beta-carotene in axenic cultures of the blue-green algae Anabaena variabilis. The results indicate that both in acetone extracts and in blue-green algae cultures these pigments were most sensitive to light and oxygen; temperatures of up to 25oC had no marked influence on these compounds. Under anoxia in acetone solution, the stability towards light decreased in the order chlorophyll a, chlorophyll b, chlorophylls c. Chlorophyll a, moreover, was less stable than its derivatives - phaeophorbides, phaeophytins, pyrophaeophytins and steryl chlorins - but more stable than beta-carotene, in the last case also in the blue-green algae cultures. Decomposition of all the pigments proceeded mainly via the breakdown of the porphyrin macrocycle, since the decomposition products were not detected in the VIS range. On the basis of these experiments one can state that while light and oxygen may have a decisive direct influence on the distribution of chlorophylls and beta-carotene in sediments, in the natural environment, temperatures of up to 25oC may have very little immediate effect.

  11. Photogeneration of charges in microcrystalline chlorophyll a

    International Nuclear Information System (INIS)

    The electric-field and temperature dependence of hole photogeneration in chlorophyll a (Chla) have been analyzed in terms of electric-field assisted thermal dissociation of charge pairs based on Onsager theory. An excellent agreement between the experimental and theoretical values of the slope-to-intercept ratio, S/I, for the plot of photogeneration efficiency vs. electric field at low field strengths provides a proof for the applicability of the Onsager approach to the photogeneration of charges in Chla. A value of 19 nm has been obtained for Coulomb capture radius, rc, from S/I. From the temperature dependence of photogeneration, the initial separation, r0, of photogenerated electron-hole has been evaluated, and has a value of 1.24 nm. This smaller r0 compared to rc leads to a feeble dissociation probability of electron-hole pairs into free carriers, and may, among other factors, explain the low power conversion efficiencies of Chla photovoltaic cells.

  12. Nonspectroscopic imaging for quantitative chlorophyll sensing

    Science.gov (United States)

    Kim, Taehoon; Kim, Jeong-Im; Visbal-Onufrak, Michelle A.; Chapple, Clint; Kim, Young L.

    2016-01-01

    Nondestructive imaging of physiological changes in plants has been intensively used as an invaluable tool for visualizing heterogeneous responses to various types of abiotic and biotic stress. However, conventional approaches often have intrinsic limitations for quantitative analyses, requiring bulky and expensive optical instruments for capturing full spectral information. We report a spectrometerless (or spectrometer-free) reflectance imaging method that allows for nondestructive and quantitative chlorophyll imaging in individual leaves in situ in a handheld device format. The combination of a handheld-type imaging system and a hyperspectral reconstruction algorithm from an RGB camera offers simple instrumentation and operation while avoiding the use of an imaging spectrograph or tunable color filter. This platform could potentially be integrated into a compact, inexpensive, and portable system, while being of great value in high-throughput phenotyping facilities and laboratory settings.

  13. Influence of ambient sulphur dioxide on chlorophyll

    International Nuclear Information System (INIS)

    For the evaluation of the injury due to SO2 from Indraprashtha (IP) Thermal Power Plant, eight species of trees were selected. Experiment was divided in two sections. Section one include transplanted tree saplings of Bauhinia variegata, Delonix regia, Flcus benghalensis, Putranjiwa roxburghii, Morus indica, Polyalthia longifolia, Leucaena leucocephala and Tabernaemontana coronaria. Here one set of plants was transplanted to polluted site of IP and other set was maintained at non polluted site of Jawaharlal Nehru University (Ecological Nursery). Second section of the study have naturally growing trees of the same species in the vicinity of the transplanted plants. Findings of the present study show that tree species were not safe at polluted site. Maximum chlorophyll reduction occurred in Bauhinia variegata, that is 32.05% (transplanted saplings). In naturally growing trees up to 35.70% reduction was seen in B. variegata. (author). 11 refs., 2 tabs

  14. Quantifying mangrove chlorophyll from high spatial resolution imagery

    Science.gov (United States)

    Heenkenda, Muditha K.; Joyce, Karen E.; Maier, Stefan W.; de Bruin, Sytze

    2015-10-01

    Lower than expected chlorophyll concentration of a plant can directly limit photosynthetic activity, and resultant primary production. Low chlorophyll concentration may also indicate plant physiological stress. Compared to other terrestrial vegetation, mangrove chlorophyll variations are poorly understood. This study quantifies the spatial distribution of mangrove canopy chlorophyll variation using remotely sensed data and field samples over the Rapid Creek mangrove forest in Darwin, Australia. Mangrove leaf samples were collected and analyzed for chlorophyll content in the laboratory. Once the leaf area index (LAI) of sampled trees was estimated using the digital cover photography method, the canopy chlorophyll contents were calculated. Then, the nonlinear random forests regression algorithm was used to describe the relationship between canopy chlorophyll content and remotely sensed data (WorldView-2 satellite image bands and their spectral transformations), and to estimate the spatial distribution of canopy chlorophyll variation. The imagery was evaluated at full 2 m spatial resolution, as well as at decreased resampled resolutions of 5 m and 10 m. The root mean squared errors with validation samples were 0.82, 0.64 and 0.65 g/m2 for maps at 2 m, 5 m and 10 m spatial resolution respectively. The correlation coefficient was analyzed for the relationship between measured and predicted chlorophyll values. The highest correlation: 0.71 was observed at 5 m spatial resolution (R2 = 0.5). We therefore concluded that estimating mangrove chlorophyll content from remotely sensed data is possible using red, red-edge, NIR1 and NIR2 bands and their spectral transformations as predictors at 5 m spatial resolution.

  15. Science Letters: A modified chlorophyll absorption continuum index for chlorophyll estimation

    Institute of Scientific and Technical Information of China (English)

    YANG Xiao-hua; HUANG Jing-feng; WANG Fu-min; WANG Xiu-zhen; YI Qiu-xiang; WANG Yuan

    2006-01-01

    There is increasing interest in using hyperspectral data for quantitative characterization of vegetation m spatial and temporal scopes. Many spectral indices are being developed to improve vegetation sensitivity by minimizing the background influence. The chlorophyll absorption continuum index (CACI) is such a measure to calculate the spectral continuum on which the analyses are based on the area of the troughs spanned by the spectral continuum. However, different values of CACI were obtained in this method because different positions of continuums were determined by different users. Furthermore, the sensitivity of CACI to agronomic parameters such as green leaf chlorophyll density (GLCD) has been reduced because the fixed positions of continuums are determined when the red edge shifted with the change in GLCD. A modified chlorophyll absorption continuum index (MCACI) is presented in this article. The red edge inflection point (REIP) replaces the maximum reflectance point (MRP) in near-infrared (NIR) shoulder on the CACI continuum. This MCACI has been proved to increase the sensitivity and predictive power of GLCD.

  16. Photochemical reactions of chlorophyll in dehydrated photosystem II: two chlorophyll forms (680 and 700 nm).

    Science.gov (United States)

    Heber, Ulrich; Shuvalov, Vladimir A

    2005-06-01

    Lichens and phototolerant poikilohydric mosses differ from spinach leaves, fern fronds or photosensitive mosses in that they show strongly decreased Fo chlorophyll fluorescence after drying. This desiccation-induced fluorescence loss is rapidly reversible under rehydration. Fluorescence emission from Photosystem II at 685 nm was decreased more strongly by dehydration than 720 nm emission. Reaction centers of Photosystem II lose activity on dehydration and regain it on hydration. Heating of desiccated lichens increased Fo chlorophyll fluorescence. The activation energy for the reversible part of the temperature-dependent fluorescence increase was 0.045 eV, which corresponds to the energy difference between the 680 and 697 nm absorption bands. In desiccated chlorolichens such as Parmelia sulcata, heating induces the appearance of positive variable fluorescence related to the reversible reduction of QA due to overcoming the energy barrier. This is interpreted to provide information on the mechanism of photoprotection: energy is dissipated by changing Chl680 or P680 into a chlorophyll form, which absorbs at 700 nm and emits light at 720 nm (Chl-720 or P680(700)) with a low quantum yield. Dissipation of light energy in this trap is activated by desiccation. PMID:16049759

  17. Effects of biocides on chlorophyll contents of detached basil leaves

    Directory of Open Access Journals (Sweden)

    Titima Arunrangsi

    2013-06-01

    Full Text Available Herbicides and insecticides have been widely and intensively used in agricultural areas worldwide to enhance crop yield. However, many biocides cause serious environmental problems. In addition, the biocides may also have some effects on the treated agricultural crops. To study effects of biocides on chlorophyll content in detached basil leaves, 2,4-D dimethylamine salt (2,4 D-Amine, paraquat, carbosulfan, and azadirachtin, were chosen as representatives of biocide. After applying the chemicals to detached basil leaves overnight in darkness, chlorophyll contents were determined. Only treatment with 2,4 D-Amine resulted in reduction of chlorophyll contents significantly compared to treatment with deionized (DI water. In the case of paraquat and carbosulfan, chlorophyll contents were not significantly changed, while slightly higher chlorophyll contents, compared to DI water, after the treatment with azadirachtin, were observed. The results indicated that 2,4 D-Amine shows an ability to accelerate chlorophyll degradation, but azadirachtin helps to retard chlorophyll degradation, when each biocide is used at the concentration recommended by the manufacturer.

  18. Regional ocean-colour chlorophyll algorithms for the Red Sea

    KAUST Repository

    Brewin, Robert J.W.

    2015-05-18

    The Red Sea is a semi-enclosed tropical marine ecosystem that stretches from the Gulf of Suez and Gulf of Aqaba in the north, to the Gulf of Aden in the south. Despite its ecological and economic importance, its biological environment is relatively unexplored. Satellite ocean-colour estimates of chlorophyll concentration (an index of phytoplankton biomass) offer an observational platform to monitor the health of the Red Sea. However, little is known about the optical properties of the region. In this paper, we investigate the optical properties of the Red Sea in the context of satellite ocean-colour estimates of chlorophyll concentration. Making use of a new merged ocean-colour product, from the European Space Agency (ESA) Climate Change Initiative, and in situ data in the region, we test the performance of a series of ocean-colour chlorophyll algorithms. We find that standard algorithms systematically overestimate chlorophyll when compared with the in situ data. To investigate this bias we develop an ocean-colour model for the Red Sea, parameterised to data collected during the Tara Oceans expedition, that estimates remote-sensing reflectance as a function of chlorophyll concentration. We used the Red Sea model to tune the standard chlorophyll algorithms and the overestimation in chlorophyll originally observed was corrected. Results suggest that the overestimation was likely due to an excess of CDOM absorption per unit chlorophyll in the Red Sea when compared with average global conditions. However, we recognise that additional information is required to test the influence of other potential sources of the overestimation, such as aeolian dust, and we discuss uncertainties in the datasets used. We present a series of regional chlorophyll algorithms for the Red Sea, designed for a suite of ocean-colour sensors, that may be used for further testing.

  19. Photoinduced electron transfer of chlorophyll in lipid bilayer system

    Indian Academy of Sciences (India)

    D K Lee; K W Seo; Y S Kang

    2002-12-01

    Photoinduced electron transfer from chlorophyll- through the interface of dipalmitoylphosphatidylcholine (DPPC) headgroup of the lipid bilayers was studied with electron magnetic resonance (EMR). The photoproduced radicals were identified with electron spin resonance (ESR) and radical yields of chlorophyll- were determined by double integration ESR spectra. The formation of vesicles was identified by changes in measured max values from diethyl ether solutions to vesicles solutions indirectly, and observed directly with SEM and TEM images. The efficiency of photosynthesis in model system was determined by measuring the amount of chlorophyll-a radical yields which were obtained from integration of ESR spectra.

  20. Chlorophyll derivatives for pest and disease control: Are they safe?

    Energy Technology Data Exchange (ETDEWEB)

    Azizullah, Azizullah, E-mail: azizswabi@gmail.com; Murad, Waheed

    2015-01-15

    Chlorophyll derivatives are getting widespread acceptance among the researchers as natural photosensitizers for photodynamic control of pests and disease vectors; however, rare attention has been given to evaluation of their toxicity to non-target organisms in the environment. This perspective article highlights that chlorophyll derivatives may not be as safe as believed and can possibly pose risk to non-target organisms in the environment. We invite the attention of environmental biologists, particularly ecotoxicologists, to contribute their role in making the application of chlorophyll derivatives more environmentally friendly and publicly acceptable.

  1. Chlorophyll derivatives for pest and disease control: Are they safe?

    International Nuclear Information System (INIS)

    Chlorophyll derivatives are getting widespread acceptance among the researchers as natural photosensitizers for photodynamic control of pests and disease vectors; however, rare attention has been given to evaluation of their toxicity to non-target organisms in the environment. This perspective article highlights that chlorophyll derivatives may not be as safe as believed and can possibly pose risk to non-target organisms in the environment. We invite the attention of environmental biologists, particularly ecotoxicologists, to contribute their role in making the application of chlorophyll derivatives more environmentally friendly and publicly acceptable

  2. Changes of Photosystem Ⅱ Electron Transport in the Chlorophyll-deficient Oilseed Rape Mutant Studied by Chlorophyll Fluorescence and Thermoluminescence

    Institute of Scientific and Technical Information of China (English)

    Jun-Wei Guo; Jin-Kui Guo; Yun Zhao; Lin-Fang Du

    2007-01-01

    The photosystem Ⅱ (PSII) complex of photosynthetic membranes comprises a number of chlorophyll-binding proteins that are important to the electron flow. Here we report that the chlorophyll b-deficient mutant has de creased the amount of light-harvesting complexes with an increased amount of some core polypeptides of PSII,including CP43 and CP47. By means of chlorophyll fluorescence and thermoluminescence, we found that the ratio of Fv/Fm, qP and electron transport rate in the chlorophyll b-deficient mutant was higher compared to the wild type.In the chlorophyll b-deficient mutant, the decay of the primary electron acceptor quinones (QA-) reoxidation was decreased, measured by the fluorescence. Furthermore, the thermolumlnescence studies in the chlorophyll b deficient mutant showed that the B band (S2/S3QB-) decreased slightly and shifted up towards higher temperatures.In the presence of dichlorophenyl-dimethylurea, which is inhibited in the electron flow to the second electron acceptor quinines (QB) at the PSII acceptor side, the maximum of the Q band (S2QA-) was decreased slightly and shifted down to lower temperatures, compared to the wild type. Thus, the electron flow within PSll of the chlorophyll b-deficient mutant was down-regulated and characterized by faster oxidation of the primary electron acceptor quinine QA- via forward electron flow and slower reduction of the oxidation S states.

  3. Remote sensing of chlorophyll fluorescence with GOSAT

    Science.gov (United States)

    Somkuti, Peter; Boesch, Hartmut; Parker, Robert

    2015-04-01

    Sun-induced chlorophyll fluorescence (Fs) emitted by plants as a by-product during photosynthesis carries information about their photosynthetic activity. It is possible to exploit space-based remote sensing measurements to retrieve the fluorescence signal and thus indirectly study carbon fluxes on a global scale. We implement a fluorescence retrieval based on the method pioneered by Frankenberg et al. (2011) into the framework of the University of Leicester Full-Physics GOSAT CO2 retrieval (UoL-FP). This physically-based approach is applied to high-resolution spectra at the edges of the O2 A-Band in the red to NIR range, that feature strong solar as well as a few weak O2 absorption lines. The fluorescence signal, which acts as an additional source, results in an in-filling of the measured solar absorption lines that are used to distinguish Fs from reflectance effects. By analysing GOSAT soundings from 2009 onwards, we examine global and regional long-term trends of Fs and compare them with parameters related to plant physiology, such as spectral vegetation indices and MODIS-derived model GPP values. Following Guanter et al. (2012) and Frankenberg et al. (2011), different regions and biomes are considered and we find that seasonal trends of both model GPP data as well as greenness indicators are well reproduced by our GOSAT-retrieved Fs.

  4. Photogeneration of charges in microcrystalline chlorophyll a

    Energy Technology Data Exchange (ETDEWEB)

    Kassi, Hassan [Scientech R and D, Inc., 2200 Rue Didbec S., Bureau 203, Trois-Rivieres, Trois-Rivieres, QC, G8Z 4H1 (Canada); Barazzouk, Said, E-mail: barazzos@uqtr.c [Groupe de Recherche en Biologie Vegetale, Universite du Quebec a Trois-Rivieres, Trois-Rivieres, QC, G9A 5H7 (Canada); Brullemans, Marc [Groupe de Recherche en Biologie Vegetale, Universite du Quebec a Trois-Rivieres, Trois-Rivieres, QC, G9A 5H7 (Canada); Leblanc, Roger M. [Department of Chemistry, University of Miami, P.O. Box 249118, Coral Gables, FL 33124-0431 (United States); Hotchandani, Surat [Groupe de Recherche en Biologie Vegetale, Universite du Quebec a Trois-Rivieres, Trois-Rivieres, QC, G9A 5H7 (Canada)

    2010-07-01

    The electric-field and temperature dependence of hole photogeneration in chlorophyll a (Chla) have been analyzed in terms of electric-field assisted thermal dissociation of charge pairs based on Onsager theory. An excellent agreement between the experimental and theoretical values of the slope-to-intercept ratio, S/I, for the plot of photogeneration efficiency vs. electric field at low field strengths provides a proof for the applicability of the Onsager approach to the photogeneration of charges in Chla. A value of 19 nm has been obtained for Coulomb capture radius, r{sub c}, from S/I. From the temperature dependence of photogeneration, the initial separation, r{sub 0}, of photogenerated electron-hole has been evaluated, and has a value of 1.24 nm. This smaller r{sub 0} compared to r{sub c} leads to a feeble dissociation probability of electron-hole pairs into free carriers, and may, among other factors, explain the low power conversion efficiencies of Chla photovoltaic cells.

  5. Relationship between chlorophyll-a and column primary production

    Digital Repository Service at National Institute of Oceanography (India)

    Dalal, S.G.; Bhargava, R.M.S.

    Relationship between surface chlorophyll a and column primary production has been established to help in estimating the latter more quickly and accurately. The equation derived is Primary Production, y = 0.54 Ln Chl a - 0.6. The relationship...

  6. Assessment of water pollution by airborne measurement of chlorophyll

    Science.gov (United States)

    Arvesen, J. C.; Weaver, E. C.; Millard, J. P.

    1972-01-01

    Remote measurement of chlorophyll concentrations to determine extent of water pollution is discussed. Construction and operation of radiometer to provide measurement capability are explained. Diagram of equipment is provided.

  7. Remote sensing of tidal chlorophyll-a variations in estuaries

    Science.gov (United States)

    Catts, Glenn P.; Khorram, Siamak; Cloern, James E.; Knight, Allen W.; Degloria, Stephen D.

    1985-01-01

    Simultaneous acquisition of surface chlorophyll-a concentrations for 39 samples from boats and Daedalus 1260 Multispectral Scanner data from a U-2 aircraft was conducted in the northern reaches of San Francisco Bay on 28 August 1980. These data were used to develop regression models for predicting surface chlorophyll-a concentrations over the study area for ebb-tide (8.40 a.m. P.D.T. (Pacific Daylight Time)) and flood-tide (3.10 p.m. P.D.T.) conditions. After selection of a single ‘best fitting’ model for both morning and afternoon data sets, the chlorophyll-a concentration was predicted for ebb and flood tide for the entire study area at approximately 40m × 40m resolution. The predicted spatial display of chlorophyll-a revealed a localized area of high phytoplankton biomass that has been inferred from field surveys and appears to be a common summer phenomenon.

  8. Instrumentation in Developing Chlorophyll Fluorescence Biosensing: A Review

    OpenAIRE

    Millan-Almaraz, Jesus R.; Guevara-Gonzalez, Ramon G.; Irineo Torres-Pacheco; Romero-Troncoso, Rene J.; Contreras-Medina, Luis M.; Carlos Duarte-Galvan; Fernandez-Jaramillo, Arturo A.

    2012-01-01

    Chlorophyll fluorescence can be defined as the red and far-red light emitted by photosynthetic tissue when it is excited by a light source. This is an important phenomenon which permits investigators to obtain important information about the state of health of a photosynthetic sample. This article reviews the current state of the art knowledge regarding the design of new chlorophyll fluorescence sensing systems, providing appropriate information about processes, instrumentation and electronic...

  9. Quantification of plant chlorophyll content using Google Glass.

    Science.gov (United States)

    Cortazar, Bingen; Koydemir, Hatice Ceylan; Tseng, Derek; Feng, Steve; Ozcan, Aydogan

    2015-04-01

    Measuring plant chlorophyll concentration is a well-known and commonly used method in agriculture and environmental applications for monitoring plant health, which also correlates with many other plant parameters including, e.g., carotenoids, nitrogen, maximum green fluorescence, etc. Direct chlorophyll measurement using chemical extraction is destructive, complex and time-consuming, which has led to the development of mobile optical readers, providing non-destructive but at the same time relatively expensive tools for evaluation of plant chlorophyll levels. Here we demonstrate accurate measurement of chlorophyll concentration in plant leaves using Google Glass and a custom-developed software application together with a cost-effective leaf holder and multi-spectral illuminator device. Two images, taken using Google Glass, of a leaf placed in our portable illuminator device under red and white (i.e., broadband) light-emitting-diode (LED) illumination are uploaded to our servers for remote digital processing and chlorophyll quantification, with results returned to the user in less than 10 seconds. Intensity measurements extracted from the uploaded images are mapped against gold-standard colorimetric measurements made through a commercially available reader to generate calibration curves for plant leaf chlorophyll concentration. Using five plant species to calibrate our system, we demonstrate that our approach can accurately and rapidly estimate chlorophyll concentration of fifteen different plant species under both indoor and outdoor lighting conditions. This Google Glass based chlorophyll measurement platform can display the results in spatiotemporal and tabular forms and would be highly useful for monitoring of plant health in environmental and agriculture related applications, including e.g., urban plant monitoring, indirect measurements of the effects of climate change, and as an early indicator for water, soil, and air quality degradation. PMID:25669673

  10. Quantification of Plant Chlorophyll Content Using Google Glass

    OpenAIRE

    Cortazar, Bingen; Koydemir, Hatice Ceylan; Tseng, Derek; Feng, Steve; Ozcan, Aydogan

    2015-01-01

    Measuring plant chlorophyll concentration is a well-known and commonly used method in agriculture and environmental applications for monitoring plant health, which also correlates with many other plant parameters including, e.g., carotenoids, nitrogen, maximum green fluorescence, etc. Direct chlorophyll measurement using chemical extraction is destructive, complex and time-consuming, which has led to the development of mobile optical readers, providing non-destructive but at the same time rel...

  11. Lil3 Assembles with Proteins Regulating Chlorophyll Synthesis in Barley.

    Directory of Open Access Journals (Sweden)

    Astrid Mork-Jansson

    Full Text Available The light-harvesting-like (LIL proteins are a family of membrane proteins that share a chlorophyll a/b-binding motif with the major light-harvesting antenna proteins of oxygenic photoautotrophs. LIL proteins have been associated with the regulation of tetrapyrrol biosynthesis, and plant responses to light-stress. Here, it was found in a native PAGE approach that chlorophyllide, and chlorophyllide plus geranylgeraniolpyrophosphate trigger assembly of Lil3 in three chlorine binding fluorescent protein bands, termed F1, F2, and F3. It is shown that light and chlorophyllide trigger accumulation of protochlorophyllide-oxidoreductase, and chlorophyll synthase in band F3. Chlorophyllide and chlorophyll esterified to geranylgeraniol were identified as basis of fluorescence recorded from band F3. A direct interaction between Lil3, CHS and POR was confirmed in a split ubiquitin assay. In the presence of light or chlorophyllide, geranylgeraniolpyrophosphate was shown to trigger a loss of the F3 band and accumulation of Lil3 and geranylgeranyl reductase in F1 and F2. No direct interaction between Lil3 and geranylgeraniolreductase was identified in a split ubiquitin assay; however, accumulation of chlorophyll esterified to phytol in F1 and F2 corroborated the enzymes assembly. Chlorophyll esterified to phytol and the reaction center protein psbD of photosystem II were identified to accumulate together with psb29, and APX in the fluorescent band F2. Data show that Lil3 assembles with proteins regulating chlorophyll synthesis in etioplasts from barley (Hordeum vulgare L..

  12. Variability of the specific fluorescence of chlorophyll in the ocean. Part 2. Fluorometric method of chlorophyll a determination

    OpenAIRE

    Miros³awa Ostrowska; Dimitrii N. Matorin; Dariusz Ficek

    2000-01-01

    Two methods of determining the chlorophyll a concentration in the sea have been formulated on the basis of artificially induced fluorescence measured with the aid of submersible fluorometers. The method of statistical correlation is founded on the empirical relationship between fluorescence and chlorophyll concentration. The theoretical model of fluorescence described in Part 1 of this paper (see Ostrowska et al. 2000, this volume) provides the basis of the other method, the physical...

  13. Evaluation of nitrogen status and total chlorophyll in longkong (Aglaia dookkoo Griff. leaves under water stress using a chlorophyll meter

    Directory of Open Access Journals (Sweden)

    Sdoodee, S.

    2005-07-01

    Full Text Available A chlorophyll meter (SPAD-502 was used to assess nitrogen status and total chlorophyll in longkong leaves, leaves from twelve of 10-year-old trees grown in the experimental plot at Prince of Songkla University, Songkhla province. The relationship between SPAD-502 meter reading and nitrogen status and total chlorophyll content analyzed in the laboratory was evaluated during 8 months (May-December 2003. It was found that the trend of the relationships in each month was similar. There was no significant differenceamong regression linears of all months. The data of 8 months showed that SPAD-reading and nitrogen content, and SPAD-reading and total chlorophyll content were related in a positive manner. They were Y = 0.19X+10.10, r = 0.76** (n = 240, and Y = 0.43X-7.89, r = 0.79** (n = 400, respectively. The SPAD-502 was then used to assess total nitrogen and total chlorophyll content during imposed water stress. Fifteen 4-yearold plants were grown in pots (each pot containing 50 kg soil volume. The experiment was arranged in acompletely randomized design with 3 treatments: (1 daily watering (2 once watering on day 7 (3 no watering with 5 replications during 14 days of the experimental period. Measurements showed a continuous decrease of SPAD-reading in the treatment of no watering. On day 14, a significant difference of SPAD- reading values between the treatment of daily watering and no watering was found. Then, the values of nitrogen content and total chlorophyll were assessed by using the linear regression equations. From the result, it is suggested that the measurement by chlorophyll meter is a rapid technique for the evaluation of total chlorophyll and nitrogen status in longkong leaves during water stress.

  14. HPLC Analysis of Chlorophyll a, Chlorophyll b, and Beta-Carotene in Collard Greens: A Project for a Problem-Oriented Laboratory Course.

    Science.gov (United States)

    Silveira, Augustine, Jr.; And Others

    1984-01-01

    High performance liquid chromatography (HPLC) is used to separate and quantitate beta-carotene, chlorophyll a, and chlorophyll b originating from collard greens. Experimental procedures used and typical results obtained are discussed. (JN)

  15. Chlorophyll biosynthesis and assembly into chlorophyll-protein complexes in isolated developing chloroplasts

    International Nuclear Information System (INIS)

    Isolated developing plastids from greening cucumber cotyledons or from photoperiodically grown pea seedlings incorporated 14C-labeled 5-aminolevulinic acid (ALA) into chlorophyll (Chl). Incorporation was light dependent, enhanced by S-adenosylmethionine, and linear for 1 hr. The in vitro rate of Chl synthesis from ALA was comparable to the in vivo rate of Chl accumulation. Levulinic acid and dioxoheptanoic acid strongly inhibited Chl synthesis but not plastid protein synthesis. Neither chloramphenicol nor spectinomycin affected Chl synthesis, although protein synthesis was strongly inhibited. Components of thylakoid membranes from plastids incubated with [14C]ALA were resolved by electrophoresis and then subjected to autoradiography. This work showed that (i) newly synthesized Chl was assembled into Chl-protein complexes and (ii) the inhibition of protein synthesis during the incubation did not alter the labeling pattern. Thus, there was no observable short-term coregulation between Chl synthesis (from ALA) and the synthesis of membrane proteins in isolated plastids

  16. Mechanism of lanthanum effect on chlorophyll of spinach

    Institute of Scientific and Technical Information of China (English)

    洪法水; 魏正贵; 赵贵文

    2002-01-01

    The mechanism of La3+ effect on chlorophyll (chl) of spinach in solution culture has been studied. The results show that La3+ can obviously promote growth, increase chlorophyll contents and photosynthetic rate of spinach. La3+ may substitute Mg2+ for chlorophyll formation of spinach when there is no Mg2+ in solution. La3+ improves significantly PSII formation and enhances electron transport rate of PSII. By ICP-MS and atom absorption spectroscopy methods, it has been revealed that rare earth elements (REEs) can enter chloroplasts and increase Mg2+-chl contents; and REEs bind to chlorophyll and also form REE-chl. REE-chl is about 72% in total chlorophyll with La3+ treatment and without Mg2+ in solution. By UV-Vis, FT-IR and extended X-ray absorption fine structure spectroscopy (EXAFS) methods, it has been found that La3+ coordinates with nitrogen of porphyrin rings with the average La-N bond length of 0.253 nm.

  17. Instrumentation in Developing Chlorophyll Fluorescence Biosensing: A Review

    Directory of Open Access Journals (Sweden)

    Jesus R. Millan-Almaraz

    2012-08-01

    Full Text Available Chlorophyll fluorescence can be defined as the red and far-red light emitted by photosynthetic tissue when it is excited by a light source. This is an important phenomenon which permits investigators to obtain important information about the state of health of a photosynthetic sample. This article reviews the current state of the art knowledge regarding the design of new chlorophyll fluorescence sensing systems, providing appropriate information about processes, instrumentation and electronic devices. These types of systems and applications can be created to determine both comfort conditions and current problems within a given subject. The procedure to measure chlorophyll fluorescence is commonly split into two main parts; the first involves chlorophyll excitation, for which there are passive or active methods. The second part of the procedure is to closely measure the chlorophyll fluorescence response with specialized instrumentation systems. Such systems utilize several methods, each with different characteristics regarding to cost, resolution, ease of processing or portability. These methods for the most part include cameras, photodiodes and satellite images.

  18. An overview of remote sensing of chlorophyll fluorescence

    Science.gov (United States)

    Xing, Xiao-Gang; Zhao, Dong-Zhi; Liu, Yu-Guang; Yang, Jian-Hong; Xiu, Peng; Wang, Lin

    2007-03-01

    Besides empirical algorithms with the blue-green ratio, the algorithms based on fluorescence are also important and valid methods for retrieving chlorophyll-a concentration in the ocean waters, especially for Case II waters and the sea with algal blooming. This study reviews the history of initial cognitions, investigations and detailed approaches towards chlorophyll fluorescence, and then introduces the biological mechanism of fluorescence remote sensing and main spectral characteristics such as the positive correlation between fluorescence and chlorophyll concentration, the red shift phenomena. Meanwhile, there exist many influence factors that increase complexity of fluorescence remote sensing, such as fluorescence quantum yield, physiological status of various algae, substances with related optical property in the ocean, atmospheric absorption etc. Based on these cognitions, scientists have found two ways to calculate the amount of fluorescence detected by ocean color sensors: fluorescence line height and reflectance ratio. These two ways are currently the foundation for retrieval of chlorophyl l - a concentration in the ocean. As the in-situ measurements and synchronous satellite data are continuously being accumulated, the fluorescence remote sensing of chlorophyll-a concentration in Case II waters should be recognized more thoroughly and new algorithms could be expected.

  19. Modeling of estuarne chlorophyll a from an airborne scanner

    Science.gov (United States)

    Khorram, Siamak; Catts, Glenn P.; Cloern, James E.; Knight, Allen W.

    1987-01-01

    Near simultaneous collection of 34 surface water samples and airborne multispectral scanner data provided input for regression models developed to predict surface concentrations of estuarine chlorophyll a. Two wavelength ratios were employed in model development. The ratios werechosen to capitalize on the spectral characteristics of chlorophyll a, while minimizing atmospheric influences. Models were then applied to data previously acquired over the study area thre years earlier. Results are in the form of color-coded displays of predicted chlorophyll a concentrations and comparisons of the agreement among measured surface samples and predictions basedon coincident remotely sensed data. The influence of large variations in fresh-water inflow to the estuary are clearly apparent in the results. The synoptic view provided by remote sensing is another method of examining important estuarine dynamics difficult to observe from in situ sampling alone.

  20. Optimal leaf positions for chlorophyll meter measurement in rice

    Directory of Open Access Journals (Sweden)

    Zhaofeng eYuan

    2016-05-01

    Full Text Available The Soil Plant Analysis Development (SPAD chlorophyll meter is one of the most commonly used diagnostic tools to measure crop nitrogen status. However, the measurement method of the meter could significantly affect the accuracy of the final estimation. Thus, this research was undertaken to develop a new methodology to optimize SPAD meter measurements in rice (Oryza sativa L.. A flatbed color scanner was used to map the dynamic chlorophyll distribution and irregular leaf shapes. Calculus algorithm was adopted to estimate the potential positions for SPAD meter measurement along the leaf blade. Data generated by the flatbed color scanner and SPAD meter were analysed simultaneously. The results suggested that a position 2/3 of the distance from the leaf base to the apex (2/3 position could represent the chlorophyll content of the entire leaf blade, as indicated by the relatively low variance of measurements at that positon. SPAD values based on di-positional leaves and the extracted chlorophyll a and b contents were compared. This comparison showed that the 2/3 position on the lower leaves tended to be more sensitive to changes in chlorophyll content. Finally, the 2/3 position and average SPAD values of the fourth fully expanded leaf from the top were compared with leaf nitrogen concentration. The results showed the 2/3 position on that leaf was most suitable for predicting the nitrogen status of rice. Based on these results, we recommend making SPAD measurements at the 2/3 position on the fourth fully expanded leaf from the top. The coupling of dynamic chlorophyll distribution and irregular leaf shapes information can provide a promising approach for the calibration of SPAD meter measurement, which can further benefit the in situ nitrogen management by providing reliable estimation of crops nitrogen nutrition status.

  1. Investigating the Control of Chlorophyll Degradation by Genomic Correlation Mining.

    Science.gov (United States)

    Ghandchi, Frederick P; Caetano-Anolles, Gustavo; Clough, Steven J; Ort, Donald R

    2016-01-01

    Chlorophyll degradation is an intricate process that is critical in a variety of plant tissues at different times during the plant life cycle. Many of the photoactive chlorophyll degradation intermediates are exceptionally cytotoxic necessitating that the pathway be carefully coordinated and regulated. The primary regulatory step in the chlorophyll degradation pathway involves the enzyme pheophorbide a oxygenase (PAO), which oxidizes the chlorophyll intermediate pheophorbide a, that is eventually converted to non-fluorescent chlorophyll catabolites. There is evidence that PAO is differentially regulated across different environmental and developmental conditions with both transcriptional and post-transcriptional components, but the involved regulatory elements are uncertain or unknown. We hypothesized that transcription factors modulate PAO expression across different environmental conditions, such as cold and drought, as well as during developmental transitions to leaf senescence and maturation of green seeds. To test these hypotheses, several sets of Arabidopsis genomic and bioinformatic experiments were investigated and re-analyzed using computational approaches. PAO expression was compared across varied environmental conditions in the three separate datasets using regression modeling and correlation mining to identify gene elements co-expressed with PAO. Their functions were investigated as candidate upstream transcription factors or other regulatory elements that may regulate PAO expression. PAO transcript expression was found to be significantly up-regulated in warm conditions, during leaf senescence, and in drought conditions, and in all three conditions significantly positively correlated with expression of transcription factor Arabidopsis thaliana activating factor 1 (ATAF1), suggesting that ATAF1 is triggered in the plant response to these processes or abiotic stresses and in result up-regulates PAO expression. The proposed regulatory network includes the

  2. Ecology: a niche for cyanobacteria containing chlorophyll d

    DEFF Research Database (Denmark)

    Kühl, Michael; Chen, Min; Ralph, Peter J;

    2005-01-01

    The cyanobacterium known as Acaryochloris marina is a unique phototroph that uses chlorophyll d as its principal light-harvesting pigment instead of chlorophyll a, the form commonly found in plants, algae and other cyanobacteria; this means that it depends on far-red light for photosynthesis. Here...... we demonstrate photosynthetic activity in Acaryochloris-like phototrophs that live underneath minute coral-reef invertebrates (didemnid ascidians) in a shaded niche enriched in near-infrared light. This discovery clarifies how these cyanobacteria are able to thrive as free-living organisms...

  3. Endolithic chlorophyll d-containing phototrophs

    DEFF Research Database (Denmark)

    Behrendt, Lars; Larkum, Anthony W D; Norman, Anders;

    2011-01-01

    Cyanobacteria in the genus Acaryochloris are the only known oxyphototrophs that have exchanged chlorophyll a (Chl a) with Chl d as their primary photopigment, facilitating oxygenic photosynthesis with near infrared (NIR) light. Yet their ecology and natural habitats are largely unknown. We used...... hyperspectral and variable chlorophyll fluorescence imaging, scanning electron microscopy, photopigment analysis and DNA sequencing to show that Acaryochloris-like cyanobacteria thrive underneath crustose coralline algae in a widespread endolithic habitat on coral reefs. This finding suggests an important role...... of Chl d-containing cyanobacteria in a range of hitherto unexplored endolithic habitats, where NIR light-driven oxygenic photosynthesis may be significant....

  4. Chlorophyll a fluorescence to phenotype wheat genotypes for heat tolerance

    DEFF Research Database (Denmark)

    Sharma, Dew Kumari; Andersen, Sven Bode; Ottosen, Carl-Otto;

    . Chlorophyll a fluorescence has been a versatile tool in photosynthesis research to measure plant responses to various abiotic stresses that affect PSII. We aim to establish a reproducible protocol to measure response of wheat genotypes to high temperature, based on the physiological marker, maximum quantum......%. Our protocol seems to be stable over environments since interaction between genotypes and the three repeated experiments separated in time was not statistically significant. The chlorophyll a fluorescence protocol may enable identification of wheat lines reliably more or less tolerant to heat stress...

  5. Measurement of Sun Induced Chlorophyll Fluorescence Using Hyperspectral Satellite Imagery

    Science.gov (United States)

    Irteza, S. M.; Nichol, J. E.

    2016-06-01

    Solar Induced Chlorophyll Fluorescence (SIF), can be used as an indicator of stress in vegetation. Several scientific approaches have been made and there is considerable evidence that steady state Chlorophyll fluorescence is an accurate indicator of plant stress hence a reliable tool to monitor vegetation health status. Retrieval of Chlorophyll fluorescence provides an insight into photochemical and carbon sequestration processes within vegetation. Detection of Chlorophyll fluorescence has been well understood in the laboratory and field measurement. Fluorescence retrieval methods were applied in and around the atmospheric absorption bands 02B (Red wavelength) approximately 690 nm and 02A (Far red wavelengths) 740 nm. Hyperion satellite images were acquired for the years 2012 to 2015 in different seasons. Atmospheric corrections were applied using the 6S Model. The Fraunhofer Line Discrimanator (FLD) method was applied for retrieval of SIF from the Hyperion images by measuring the signal around the absorption bands in both vegetated and non vegetated land cover types. Absorption values were extracted in all the selected bands and the fluorescence signal was detected. The relationships between NDVI and Fluorescence derived from the satellite images are investigated to understand vegetation response within the absorption bands.

  6. Photoinhibition of Photosystems I and II Using Chlorophyll Fluorescence Measurements

    Science.gov (United States)

    Quiles, Maria Jose

    2005-01-01

    In this study the photoinhibition of photosystems (PS) I and II caused by exposure to high intensity light in oat ("Avena sativa," var Prevision) is measured by the emission of chlorophyll fluorescence in intact leaves adapted to darkness. The maximal quantum yield of PS II was lower in plants grown under high light intensity than in plants grown…

  7. Chlorophyll Fluorescence Analysis of Cyanobacterial Photosynthesis and Acclimation

    OpenAIRE

    Campbell, Douglas; Hurry, Vaughan; Adrian K Clarke; Gustafsson, Petter; Öquist, Gunnar

    1998-01-01

    Cyanobacteria are ecologically important photosynthetic prokaryotes that also serve as popular model organisms for studies of photosynthesis and gene regulation. Both molecular and ecological studies of cyanobacteria benefit from real-time information on photosynthesis and acclimation. Monitoring in vivo chlorophyll fluorescence can provide noninvasive measures of photosynthetic physiology in a wide range of cyanobacteria and cyanolichens and requires only small samples. Cyanobacterial fluore...

  8. Mahalanobis distance screening of Arabidopsis mutants with chlorophyll fluorescence

    Czech Academy of Sciences Publication Activity Database

    Codrea, C. C.; Hakala-Yatkin, M.; Karlund-Marttila, A.; Nedbal, Ladislav; Aittokallio, T.; Nevalainen, O. S.; Tyystjärvi, E.

    2010-01-01

    Roč. 105, č. 3 (2010), s. 273-283. ISSN 0166-8595 Institutional research plan: CEZ:AV0Z60870520 Keywords : arabidopsis thaliana * chlorophyll fluorescence * fluorescence imaging * mutant detection * outlier detection Subject RIV: EH - Ecology, Behaviour Impact factor: 2.410, year: 2010 http://www.springerlink.com/content/x3586512462pn006/

  9. Photochemical and photoelectrochemical quenching of chlorophyll fluorescence in photosystem II

    Czech Academy of Sciences Publication Activity Database

    Vredenberg, W.; Durchan, M.; Prášil, Ondřej

    2009-01-01

    Roč. 1787, č. 12 (2009), s. 1468-1478. ISSN 0005-2728 R&D Projects: GA ČR GA206/08/1683 Institutional research plan: CEZ:AV0Z50200510 Keywords : Chlorophyll a fluorescence * Photosystem II * Heterogeneity Subject RIV: EE - Microbiology, Virology Impact factor: 3.688, year: 2009

  10. Method for detecting copper complexes of chlorophyll in vegetable oils

    OpenAIRE

    Roca, María; Gallardo Guerrero, Lourdes; Gandul-Rojas, Beatriz

    2009-01-01

    [EN] The present invention relates to a method for detecting copper complexes of chlorophyll in vegetable oils and, more specifically, in olive oil. This method is of special interest for the food industry since it makes it possible to detect the presence, in the oil, of additives that are not pennitted by legislation.

  11. Chlorophyll a fluorescence to phenotype wheat genotypes for heat tolerance

    DEFF Research Database (Denmark)

    Sharma, Dew Kumari; Andersen, Sven Bode; Ottosen, Carl-Otto;

    In prospects of global climate change, heat stress is a rising constraint for the productivity of wheat (Triticum aestivum L.). It is a heat-susceptible crop beyond 17-23oC temperature throughout its phenological stages, flowering phase being the most sensitive stage. Chlorophyll a fluorescence...

  12. Laser-Induced Breakdown Spectroscopy and Chlorophyll a Flourescence Transients

    DEFF Research Database (Denmark)

    Frydenvang, Jens

    trustworthy results of a sufficient quality; something that remains a problem for many in-situ methods. In my PhD, I present my work with two such in-situ methods, Laser-Induced Breakdown Spectroscopy (LIBS) and OJIP transients, the rising part of chlorophyll a fluorescence transients from dark-adapted leaves....

  13. ECOHAB: Tester_P - Gulf of Mexico Chlorophyll - 1998-09 (NODC Accession 0000536)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Chlorophyll a is a standard measure for phytoplankton biomass. Routinely, samples for extracted chlorophyll a values are filtered at sea, stored in liquid nitrogen,...

  14. The regulatory role of reversible phosphorylation in the chlorophyll degradation pathway

    Science.gov (United States)

    Senescence represents the final stage of plant development and is characterized by several processes including the systematic degradation of the photosynthetic apparatus and chlorophyll molecules inside chloroplasts. Normally, chlorophyll is catabolized to colorless compounds through a series of enz...

  15. ECOHAB: Tester_P - Gulf of Mexico Chlorophyll - 1998-09 (NODC Accession 0000537)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Chlorophyll a is a standard measure for phytoplankton biomass. Routinely, samples for extracted chlorophyll a values are filtered at sea, stored in liquid nitrogen,...

  16. The effect of acid rain stress on chlorophyll, peroxidase of the conservation of rare earth elements

    International Nuclear Information System (INIS)

    Full text: Based on pot experiment, the effect of acid rain stress on chlorophyll, peroxidase of wheat, the relationship of them and the conservation of rare earth elements has been studied. The result showed: stress of acid rain resulted in decrease of chlorophyll content and a/b values, chlorophyll a/b value and chlorophyll content is positive correlation with pH value of acid rain: peroxidase activity was gradually rise with pH value decrease, which indirectly increased decomposition intensity of chlorophyll. Decreased content and a/b value of chlorophyll further speeded blade decay affected the transport and transformation of light energy and metabolism of carbohydrates. After being treated by rare earth elements content and pH value of chlorophyll and peroxidase activity could be relatively stable. Therefore, under lower acidity condition, rare earth elements can influence the effect of acid rain on chlorophyll and peroxidase activity of wheat

  17. Fluorometric Techniques For The Measurement Of Oceanic Chlorophyll In The Support Of Remote Sensing

    OpenAIRE

    Smith, Raymond C; Baker, Karen S.; Dustan, Phillip

    1981-01-01

    Satellite imagery is now being used to estimate the near-surface chlorophyll concentration for large ocean areas. To assess the accuracy and precision of these remote sensing techniques, contemporaneous ship and satellite data for the determination of oceanic chlorophyll concentrations have been collected. Since chlorophyll fluorometry is a widely used technique for the determination of chlorophylls at sea, our analyses have led us to review the literature of fluorometry in order to re-examin...

  18. The effect of storage temperature of cucumber fruit on chlorophyll fluorescence

    OpenAIRE

    Ryszard Kosson

    2013-01-01

    The effect of three storage temperature levels: 12,5°C, 20°C, and 1,5°C on basic indexes of chlorophyll fluorescence of cucumber fruits was studied. The greenhouse grown cucumber fruits cv. Wiktor F1 were stored in perforated polyethylene bags or without packages. The minimum chlorophyll fluorescence (Fo), maximum chlorophyll fluorescence (Fm), variable chlorophyll fluorescence (Fv) and relative variable fluorescence (Fv/Fm) of the cucumber peel were measured. Relative variable fluorescence ...

  19. Transfer of Chlorophyll Pigments from an Oily Matrix to the Instestinal Epithelial Cells

    OpenAIRE

    Gandul-Rojas, Beatriz; Gallardo Guerrero, Lourdes; Mínguez Mosquera, María Isabel

    2008-01-01

    The present work is focused on examining the factors affecting the transfer of chlorophylls from an oily food matrix to the intestinal epithelial cells during the digestive process. It was studied both chlorophyll a (Chl a) and chlorophyll b (Chl b) as the major chlorophyll derivatives present in processed vegetables common at the diet: pheophytin a (Phy a), pheophytin b (Phy b), pyropheophytin a (Pyphy a), pheophorbide a (Pho a) and pyropheophorbide a (Pypho a).

  20. Portable chlorophyll meter (PCM-502) values are related to total chlorophyll concentration and photosynthetic capacity in papaya (Carica papaya L.)

    Science.gov (United States)

    This study was carried out to verify the practical use of the portable chlorophyll meter-PCM502 (PCM) in two papaya cultivars with contrasting green coloring of the leaf blade (‘Golden’: yellowish-green; ‘Solo’: dark green). The relationship was studied between the photosynthetic process and leaf n...

  1. Integrating Biology into the General Chemistry Laboratory: Fluorometric Analysis of Chlorophyll "a"

    Science.gov (United States)

    Wesolowski, Meredith C.

    2014-01-01

    A laboratory experiment that introduces fluorometry of chlorophyll "a" at the general chemistry level is described. The use of thin-layer chromatography to isolate chlorophyll "a" from spirulina and leaf matter enables quantification of small amounts of chlorophyll "a" via fluorometry. Student results were reasonably…

  2. Sonnenlicht-induzierte Chlorophyll-Fluoreszenz im Tagesgang in Nutzpflanzenbeständen

    OpenAIRE

    Idelberger, Claudia

    2015-01-01

    Im Rahmen der Fernerkundung per Spektrometermessungen wurde die sonnenlicht-induzierte Chlorophyll-Fluoreszenz zur Feststellung des Photosynthesestatus eines Pflanzenbestandes untersucht. Aus den kinetischen Mengenverschiebungen von sonnenlicht-induzierter Chlorophyll-Fluoreszenz und Photosynthese konnte in Abdunklungsversuchen nachgewiesen werden, dass beide Outputs des Photosystems II sind. Die sonnenlicht-induzierte Chlorophyll-Fluoreszenz unterliegt einem vor allem lichtabhängigen Tagesga...

  3. Effect of automobile pollution on chlorophyll content of roadside urban trees

    Directory of Open Access Journals (Sweden)

    M. Iqbal

    2015-09-01

    Full Text Available The effect of automobile pollution was determined on chlorophyll content of four different tree species viz. Azadirachta indica L., Conocarpus erectus L., Guiacum officinale L.and Eucalyptus sp. growing along the roads of the city.  Significant changes in the level of chlorophyll “a”, chlorophyll “b” and total chlorophyll “a+b” were found in the leaves of four tree species (A. indica, C. erectus, G.officinale and Eucalyptus sp. collected from polluted sites (Airport, Malir Halt, Quaidabad as compared to control site (Karachi University Campus. Lowest concentration of chlorophyll “a”, chlorophyll “b” and chlorophyll “a+b” was recorded in the leaf samples of all tree species collected from Quaidabad site when compared with the leaf samples collected from control site. The highest levels of chlorophyll pigment were recorded in all tree species leave samples collected from Karachi University Campus.  Similarly, better levels of chlorophyll “a”, chlorophyll “b” and total chlorophyll “a+b” was observed in all tree species growing at Airport site as compared to plants growing at Malir Halt and Quaidabad sites.  This study clearly indicated that the vehicular activities induced air pollution problem and affected on the level of chlorophyll pigments in trees which were exposed to road side pollution.

  4. Two-photon excited fluorescence from higher electronic states of chlorophylls in photosynthetic antenna complexes a new approach to detect strong excitonic chlorophyll a/b coupling

    CERN Document Server

    Leupold, D; Ehlert, J; Irrgang, K D; Renger, G; Lokstein, H

    2002-01-01

    Stepwise two-photon excitation of chlorophyll a and b in the higher plant main light-harvesting complex (LHC II) and the minor complex CP29 (as well as in organic solution) with 100-fs pulses in the Q/sub y/ region results in a weak blue fluorescence. The dependence of the spectral shape of the blue fluorescence on excitation wavelength offers a new approach to elucidate the long-standing problem of the origin of spectral "chlorophyll forms" in pigment-protein complexes, in particular the characterization of chlorophyll a/b-heterodimers. As a first result we present evidence for the existence of strong chlorophyll a/b-interactions (excitonically coupled transitions at 650 and 680 nm) in LHC II at ambient temperature. In comparison with LHC II, the experiments with CP29 provide further evidence that the lowest energy chlorophyll a transition (at ~680 nm) is not excitonically coupled to chlorophyll b. (22 refs).

  5. Qtl mapping of wheat doubled haploids for chlorophyll content and chlorophyll fluorescence kinetics under drought stress imposed at anthesis stage

    International Nuclear Information System (INIS)

    Drought stress is one of the major environmental constraints to crop plants including wheat worldwide. Synthetic hexaploid can act as a vehicle for improving crop tolerance against biotic and abiotic stresses. Doubled haploid population consisting of one hundred and forty individuals derived from cross of Opata and SH223 was used in the present study to identify genomic regions associated with various quantitative attributes of physiological nature. Doubled haploid mapping population was phenotyped for chlorophyll content and chlorophyll fluorescence kinetics under control and drought stress imposed at anthesis stage. Genotyping of population was accomplished by utilizing two hundred and sixty one polymorphic Gaterslaben wheat microsatellites and Beltsville agriculture research center simple sequence repeats. Linkage map of doubled haploid population comprising of 19 linkage groups and covering map length of two thousands six hundred and twenty six (2626) cM was constructed using map maker software. Major and minor QTLs associated with quantitative traits were identified using QGene software. Major QTL for chlorophyll content (QTc.wwc-1B-S11) of doubled haploid mapping population under anthesis drought stress was mapped on chromosome 1B and explained 10.09 percent of phenotypic variation at LOD score of 5.5. Seven major and minor QTLs for PCFK of doubled haploids were identified on chromosome 1B, 7A and 7D under control and drought stress at anthesis stage. The identified QTLs are of prime importance for high resolution mapping in synthetic hexaploid wheat. Genomic synteny of doubled haploids was observed with rice chromosome 2, 4, 7 and maize chromosome 7 owing to occurrence of orthologous QTLs for chlorophyll content and chlorophyll fluorescence respectively. (author)

  6. Cylindrical aggregates of chlorophylls studied by small-angle neutron scatter

    International Nuclear Information System (INIS)

    Neutron small-angle scattering has demonstrated tubular chlorophyll aggregates formed by self-assembly of a variety of chlorophyll types in nonpolar solvents. The size and other properties of the tubular aggregates can be accounted for by stereochemical properties of the chlorophyll molecules. Features of some of the structures are remarkably similar to light harvesting chlorophyll complexes in vivo, particularly for photosynthetic bacteria. These nanotube chlorophyll structures may have applications as light harvesting biomaterials where efficient energy transfer occurs from an excited state which is highly delocalized

  7. Cylindrical aggregates of chlorophylls studied by small-angle neutron scatter

    Energy Technology Data Exchange (ETDEWEB)

    Worcester, D.L. [Univ. of Missouri, Columbus, MO (United States); Katz, J.J. [Argonne National Laboratory, IL (United States)

    1994-12-31

    Neutron small-angle scattering has demonstrated tubular chlorophyll aggregates formed by self-assembly of a variety of chlorophyll types in nonpolar solvents. The size and other properties of the tubular aggregates can be accounted for by stereochemical properties of the chlorophyll molecules. Features of some of the structures are remarkably similar to light harvesting chlorophyll complexes in vivo, particularly for photosynthetic bacteria. These nanotube chlorophyll structures may have applications as light harvesting biomaterials where efficient energy transfer occurs from an excited state which is highly delocalized.

  8. Production of Liquid Chlorophyll from The Leaves of Green Grass Jelly (Premna oblongifolia Merr.)

    OpenAIRE

    Novelina Novelina; Tuty Anggraini; Rudi Hermansyah

    2015-01-01

    Chlorophyll is known to be used as a natural dye. The last few years it is known that chlorophyll has an important role as a source of antioxidants that are good for health. The availability of sources of chlorophyll in Indonesia is very large, one of which is the green grass jelly leaves (Premna obliongifolia Merr). The research objective is to get grass jelly leaf extract as a source of chlorophyll and know the characteristics of the resulting extract chlorophyll. The process of extraction ...

  9. Chlorophyll content and culture of flax embryos in vitro

    Directory of Open Access Journals (Sweden)

    A. Petrova

    2014-02-01

    Full Text Available During in vitro cultivation of green flax embryos excised 14 days after fertilization on White's medium the chloraphylls a and b are gradually destroyed and the lamellar system of plastids is disintegrated. It was possible, to prolong somewhat the presence of chlorophyll and to enhance embryo growth by culture in the dark and by adding kinetin. Light has a stimulating effect on the germination of embryos. Streptomycin inhibits chlorophyll synthesis not earlier than at germination. Young, green embryos are unable to sumvive and develop on media without sucrose. It is supposed that photosynthesis does not occur in flax embryos in vitro, and that green embryos are not more autotrophic in vitro than those of leucoembryophytes.

  10. Estimate of Leaf Chlorophyll and Nitrogen Content in Asian Pear (Pyrus serotina Rehd. by CCM-200

    Directory of Open Access Journals (Sweden)

    Mostafa GHASEMI

    2011-03-01

    Full Text Available In many cases evaluation of chlorophyll and nitrogen content in plants need to destructive methods, more time and organic solvents. Application of chlorophyll meters save time and resources. The aim of this study was estimating of chlorophyll and nitrogen content in Asian pear leaves using non-destructive method and rapid quantification of chlorophyll by chlorophyll content meter (CCM-200. This study was conducted on 8 years old Asian pear trees during June 2008 in Tehran, Iran. To develop our regression model, the chlorophyll meter data were correlated with extracted chlorophyll and nitrogen content data obtained from DMSO and Kejeldal methods, respectively. The results showed that, there was positive and linear correlation between CCM-200 data and chlorophyll a (R�=0.7183, chlorophyll b (R�=0.8523, total chlorophyll (R�=0.90, and total nitrogen content (R�=0.76 in Asian pear leaves. Thus, it can be concluded that, CCM-200 can be used in order to predict both chlorophyll and nitrogen content in Asian pear leaves.

  11. [Vegetation index estimation by chlorophyll content of grassland based on spectral analysis].

    Science.gov (United States)

    Xiao, Han; Chen, Xiu-Wan; Yang, Zhen-Yu; Li, Huai-Yu; Zhu, Han

    2014-11-01

    Comparing the methods of existing remote sensing research on the estimation of chlorophyll content, the present paper confirms that the vegetation index is one of the most practical and popular research methods. In recent years, the increasingly serious problem of grassland degradation. This paper, firstly, analyzes the measured reflectance spectral curve and its first derivative curve in the grasslands of Songpan, Sichuan and Gongger, Inner Mongolia, conducts correlation analysis between these two spectral curves and chlorophyll content, and finds out the regulation between REP (red edge position) and grassland chlorophyll content, that is, the higher the chlorophyll content is, the higher the REIP (red-edge inflection point) value would be. Then, this paper constructs GCI (grassland chlorophyll index) and selects the most suitable band for retrieval. Finally, this paper calculates the GCI by the use of satellite hyperspectral image, conducts the verification and accuracy analysis of the calculation results compared with chlorophyll content data collected from field of twice experiments. The result shows that for grassland chlorophyll content, GCI has stronger sensitivity than other indices of chlorophyll, and has higher estimation accuracy. GCI is the first proposed to estimate the grassland chlorophyll content, and has wide application potential for the remote sensing retrieval of grassland chlorophyll content. In addition, the grassland chlorophyll content estimation method based on remote sensing retrieval in this paper provides new research ideas for other vegetation biochemical parameters' estimation, vegetation growth status' evaluation and grassland ecological environment change's monitoring. PMID:25752061

  12. Chlorophyll a and primary production in the northeastern Pacific Ocean

    Institute of Scientific and Technical Information of China (English)

    HEN Xingqun; LIN Rongeheng

    2008-01-01

    The primary production and chlorophyll a concentration of picoplankton (0.2~2μm),nanoplankton (2~20 μm) and micro- plankton (20~200 μm) are described in the northeastern Pacific Ocean near the Hawaii Islands during the six survey cruises from 1996 to 2003:DY85-4,DY95-7,DY95-8,DY95-10,DY105-11 and DY105-12.14.The primary production of carbon was in range from 76.8 to 191.9 mg/(m2·d) with an average of 116.1 mg/( m2·d) in the east region,and from 73.1 to 222.5 mg/(m2·d) with an average of 127.1 mg/( m2·d) in the west region,similar to the other oligotrophic regions of the Pacific Ocean investigated.The chlorophyll a concentration was about 0.1 mg/m3 from the surface to the 50 m depth,about 0.2-0.4 mg/m3from 50 to 100 m,and gradually decreased below the 100 m depth.The picoplankton accounted for more than 70% of the total chlorophyll a in the upper layer (surface to 125 m),but it decreased to less than 50% in depth below 125 m.The na- noplankton and microplankton combined only accounted for less than 30% of the total chlorophyll a in the upper layer,but showed a more even vertical distribution.

  13. Regional variability among nonlinear chlorophyll-phosphorus relationships in lakes

    Science.gov (United States)

    Filstrup, Christopher T.; Wagner, Tyler; Soranno, Patricia A.; Stanley, Emily H.; Stow, Craig A.; Webster, Katherine E.; Downing, John A.

    2014-01-01

    The relationship between chlorophyll a (Chl a) and total phosphorus (TP) is a fundamental relationship in lakes that reflects multiple aspects of ecosystem function and is also used in the regulation and management of inland waters. The exact form of this relationship has substantial implications on its meaning and its use. We assembled a spatially extensive data set to examine whether nonlinear models are a better fit for Chl a—TP relationships than traditional log-linear models, whether there were regional differences in the form of the relationships, and, if so, which regional factors were related to these differences. We analyzed a data set from 2105 temperate lakes across 35 ecoregions by fitting and comparing two different nonlinear models and one log-linear model. The two nonlinear models fit the data better than the log-linear model. In addition, the parameters for the best-fitting model varied among regions: the maximum and lower Chl aasymptotes were positively and negatively related to percent regional pasture land use, respectively, and the rate at which chlorophyll increased with TP was negatively related to percent regional wetland cover. Lakes in regions with more pasture fields had higher maximum chlorophyll concentrations at high TP concentrations but lower minimum chlorophyll concentrations at low TP concentrations. Lakes in regions with less wetland cover showed a steeper Chl a—TP relationship than wetland-rich regions. Interpretation of Chl a—TP relationships depends on regional differences, and theory and management based on a monolithic relationship may be inaccurate.

  14. Chlorophyll fluorescence imaging of cadmium-treated white cabbage plants

    Directory of Open Access Journals (Sweden)

    Borek M.

    2013-04-01

    Full Text Available The chlorophyll fluorescence imaging technique is a valuable tool to study the impact of heavy metal stress in plants. The aim of this paper was to investigate the influence of Cd on photosynthetic apparatus of white cabbage (Brassica oleracea subsp. capitata f. alba plants. Two cabbage cultivars ‘Ditmarska Najwcześniejsza’ (‘DN’; early and ‘Amager Polana’ (‘AP’; late were used. Cd was applied before planting seedlings (10 mg Cd kg−1 DM of soil.. Measurements were performed at the 3rd leaf after 2 weeks of planting. The level of Cd-induced stress to plants was estimated by chlorophyll (Chl content (photometrically and analyses of images and numeric values of the major fluorescence parameters of Chl (Chl fluorescence imaging system FluorCam. Cd negatively affected the chlorophyll content and Fv/Fm, Fv’/Fm’, Φ PSII and qP in leaves of early cultivar of white cabbage. However, in the case of late cv. we did not observe such distinct changes. It suggests that late cultivars. are more resistant to Cd than the early ones. Considering methodological aspect of the study, Chl fluorescence imaging can better reveal some alterations within the leaf, because numeric values of specific parameters, which are the averaged data collected from the whole leaf, cannot reflect the tissue specificity. Abbreviations: HM – heavy metal, Cd – cadmium, Chl – chlorophyll, Fv/Fm – photochemical efficiency of PSII in the dark-adapted state, F‘v’/F‘m’ – PSII maximum efficiency, Φ PSII – quantum efficiency of PSII electron transport, NPQ – nonphotochemical quenching of maximal Chl fluorescence, qP – photochemical quenching coefficient.

  15. Associations between chlorophyll a and various microcystin health advisory concentrations

    OpenAIRE

    Hollister, Jeffrey W.; Kreakie, Betty J.

    2016-01-01

    Archived source code (as an R package), data for the manuscript "Associations between chlorophyll a and various microcystin health advisory concentrations"  published in F1000Research (http://f1000research.com/articles/5-151/)  Abstract:  Cyanobacteria harmful algal blooms (cHABs) are associated with a wide range of adverse health effects that stem mostly from the presence of cyanotoxins. To help protect against these impacts, several health advisory levels ha...

  16. The Application of Variable Chlorophyll Fluorescenceto Microphytobenthic Biofilms

    OpenAIRE

    Perkins, Rupert G.; Kromkamp, Jacco C.; Serôdio, Joao; Lavaud, Johann; Jesus, Bruno; Mouget, Jean-Luc; Lefebvre, Sébastien; Forster, R. M.

    2010-01-01

    Community assemblages of diatoms, green algae andcyanobacteria comprise the microphytobenthos (MPB),which inhabit benthic sediment ecosystems (Admiraal1984; Underwood and Kromkamp 1999; Consalvey et al. 2004). Particular attention has been paid to theanalysis of intertidal soft sediment systems, e.g. cohesivemudflat and sandy substrata typical of estuarine habitats.Variable chlorophyll fluorescence has been applied tothese systems since the 1990s, in an attempt to investigatethe primary produ...

  17. Chlorophyll and carotenoid pigments in solar saltern microbial mats

    Science.gov (United States)

    Villanueva, Joan; Grimalt, Joan O.; de Wit, Rutger; Keely, Brendan J.; Maxwell, James R.

    1994-11-01

    The distributions of carotenoids, chlorophylls, and their degradation products have been studied in two microbial mat systems developed in the calcite and calcite/gypsum evaporite domains of a solar saltern system. Phormidium valderianum and Microcoleus chthonoplastes are the dominant cyanobacterial species, respectively, and large amounts of Chloroflexus-like bacteria occur in the carbonate/gypsum mat. In both systems, the major pigments are chlorophyll a, zeaxanthin, β-carotene and myxoxanthophyll, which originate from these mat-building cyanobacteria. This common feature contrasts with differences in other pigments that are specific for each mat community. Thus, chlorophyll c and fucoxanthin, reflecting diatom inputs, are only found in the calcite mat, whereas the calcite/gypsum mat contains high concentrations of bacteriochlorophylls c produced by the multicellular green filamentous bacteria. In both cases, the depth concentration profiles (0-30 and 0-40 mm) show a relatively good preservation of the cyanobacterial carotenoids, zeaxanthin, β-carotene, myxoxanthophyll, and echinenone. This contrasts with the extensive biodegradation of cyanobacterial remains observed microscopically. Fucoxanthin in the calcite mat is also transformed at a faster rate than the cyanobacterial carotenoids. Chlorophyll a, the major pigment in both mats, exhibits different transformation pathways. In the calcite/gypsum mat, it is transformed via C-13 2 carbomethoxy defunctionalization prior to loss of the phytyl chain, leading to the formation of pyrophaeophytin a and, subsequently, pyrophaeophorbide a. On the other hand, the occurrence of the enzyme chlorophyllase, attributed to diatoms in the calcite mat, gives rise to extensive phytyl hydrolysis, with the formation of chlorophyllide a, pyrophaeophorbide a and, in minor proportion, phaeophorbide a. Studies of the sources of the photosynthetic pigments and of their transformation pathways in such simplified ecosystems provide a

  18. Quantifying global marine isoprene fluxes using MODIS chlorophyll observations

    OpenAIRE

    Palmer, P.I.; Shaw, S. L.

    2005-01-01

    We report global distributions of marine isoprene flux, whose source is estimated by combining an empirical relationship for isoprene production rate with MODIS satellite chlorophyll observations from 2001. We use a steady-state water column model including losses to chemistry, bacteria, and air-sea exchange. Physical mixing is a negligible sink. Flux estimates range from 107–109 molecules cm−2s−1, with considerable spatial and temporal variability, resulting in a global annual total of 0.1 T...

  19. Declining ocean chlorophyll under unabated anthropogenic CO2 emissions

    International Nuclear Information System (INIS)

    Photosynthetic assimilation of carbon dioxide and inorganic nutrients by phytoplankton constitutes a necessary prerequisite for sustaining marine life. This process is tightly linked to the concentration of chlorophyll in the ocean's euphotic zone. According to a recent field study marine chlorophyll(a) concentrations have declined over the last century with an estimated global rate of 1.0% of the global median per year. Here we attempt to identify possible mechanisms which could explain such trends. We explore these questions using an ocean general circulation model forced with documented historic and projected future anthropogenic emissions of carbon dioxide according to the IPCC SRES A1FI emission scenario until the year 2100. We further extend the time period covered by the A1FI scenario by assuming a linear decline in emissions from 2100 to 2200 and keeping them at zero levels until 2400. Our numerical simulations reveal only weak reductions in chlorophyll(a) concentrations during the twentieth century, but project a 50% decline between 2000 and 2200. We identify a local and a remotely acting mechanism for this reduction in the North Atlantic: (I) increased sea surface temperatures reduce local deep mixing and, hence, reduce the nutrient supply from waters at intermediate depths; (II) a steady shoaling of the Atlantic overturning cell tends to transport increasingly nutrient depleted waters from the Southern Hemisphere toward the north, leading to further diminishment of nutrient supply. These results provide support for a temperature-driven decline in ocean chlorophyll(a) and productivity, but suggest that additional mechanisms need to be invoked to explain observed declines in recent decades.

  20. QTLs for Rice Leaf Chlorophyll Content Under Low N Stress

    Institute of Scientific and Technical Information of China (English)

    FANG Ping; YU Xiao-Min; ZHU Ri-Qing; WU Ping

    2004-01-01

    Quantitative trait loci (QTLs) for chlorophyll content of a rice leaf were mapped on to the molecular marker linkage nutrient solution and soil culture experiments to detect rice nitrogen nutrition status under low N stress. A chlorophyll meter was used to measure the soil plant analysis development (SPAD) value of the topmost fully expanded leaf as the index of chlorophyll content that expressed nitrogen status in rice plants. Totally 3 QTLs for SPAD values, two on chromosome 3 located at interval RG179-CDO337 and RG348-RZ329, respectively, and one on chromosome 10 at interval RZ500-RG134, were detected under stressed conditions of low N in the soil and/or nutrient solution culture experiments.One QTL located at interval RG179-CDO337 on chromosome 3 associated with a relative change in SPAD value from a high N level to a low N level in the soil culture experiment was also detected. Based on the different responses to low N stress between the two parents, it was supposed that the QTLs identified in this study associated with nitrogen efficiency in rice at low N levels might be useful in applying marker technology to rice breeding programs.

  1. [Pigment composition and photosynthetic activity of pea chlorophyll mutants].

    Science.gov (United States)

    Ladygin, V G

    2003-01-01

    Pea chlorophyll mutants chlorotica 2004 and 2014 have been studied. The mutants differ from the initial form (pea cultivar Torsdag) in stem and leaf color (light green in the mutant 2004 and yellow-green in the mutant 2014), relative chlorophyll content (approximately 80 and 50%, respectively), and the composition of carotenoids: the mutant 2004 contains a significantly smaller amount of carotene but accumulates more lutein and violaxanthine; in the mutant 2014, the contents of all carotenoids are decreased proportionally to the decrease in chlorophyll content. It is shown that the rates of CO2 assimilation and oxygen production in the mutant chlorotica 2004 and 2014 plants are reduced. The quantum efficiency of photosynthesis in the mutants is 29-30% lower than in the control plants; in their hybrids, however, it is 1.5-2 higher. It is proposed that both the greater role of dark respiration in gas exchange and the reduced photosynthetic activity in chlorotica mutants are responsible for the decreased phytomass increment in these plants. On the basis of these results, the conclusion is drawn that the mutations chlorotica 2004 and 2014 affect the genes controlling the formation and functioning of various components of the photosynthetic apparatus. PMID:12942751

  2. Normal-Phase Open Column versus Reversed-Phase High Performance Liquid Chromatography: Separation of Chlorophyll a and Chlorophyll b from their Diastereomers.

    Science.gov (United States)

    Schaber, Peter M.

    1985-01-01

    Background information, procedures used, and typical results obtained are provided for an experiment involving the separation of chlorophyll a and chlorophyll b from their diastereomers. Reasons why the experiment can be easily integrated into most laboratory curricula where high-performance liquid chromatography capabilities exist are given. (JN)

  3. Electrical characteristics of chlorophyll-a polyvinyl alcohol photovoltaic cells

    Institute of Scientific and Technical Information of China (English)

    HAN, Yun-Yu(韩允雨); DIAO, Zhao-Yu*(刁兆玉); LI, Huai-Xiang(李怀祥); CHI, Yan-Hui(迟颜辉)

    2000-01-01

    A type of photovoltaic cell was made by sandwiching microcrystalline chlorophyll-a (chla) layer and polyvinyl alcohol (PVA) film between two semiconductive optical transparent SnO2 electrodes, such as SnO2/chla/PVA/SnO2. The cell showed a dark rectifying effect and presented photovaltaic properties on illumination, which was illustrated by the charge distribution in the cell. It was suggested that the SnO2/chla junction might be responsible for photovaltage and the chla/PVA for the charge separation upon irradiation of visible light. The equivalent electric circuit was discussed and its equivalent component values were calculated.

  4. Simple heterogeneity parametrization for sea surface temperature and chlorophyll

    Science.gov (United States)

    Skákala, Jozef; Smyth, Timothy J.

    2016-06-01

    Using satellite maps this paper offers a complex analysis of chlorophyll & SST heterogeneity in the shelf seas around the southwest of the UK. The heterogeneity scaling follows a simple power law and is consequently parametrized by two parameters. It is shown that in most cases these two parameters vary only relatively little with time. The paper offers a detailed comparison of field heterogeneity between different regions. How much heterogeneity is in each region preserved in the annual median data is also determined. The paper explicitly demonstrates how one can use these results to calculate representative measurement area for in situ networks.

  5. Probing of chlorophyll a with pulsed tunable laser

    International Nuclear Information System (INIS)

    Probing with a tunable pulsed dye laser of a solution of chlorophyll a in pyridine is reported. Transmission studies at fixed wavelengths as function of laser intensity reveal that various levels within the singlet and triplet system become populated and the life-time of these excited states is determined. Fluorescence in the blue part of the electromagnetic spectrum is recorded and the spectrum is induced as a result of the consecutive absorption of two red photons. Using time resolved spectroscopical detection methods, the fluorescence spectra of dimers, free from interference of that due to the monomer, are recorded. (orig.)

  6. Influence of water-based ferrofluid upon chlorophylls in cereals

    International Nuclear Information System (INIS)

    The present experimental investigation was focused on the study of the simultaneous influence of the water-based ferrofluid and static magnetic field exposure on young cereal plants. Water-based ferrofluid, stabilized with citric acid was added daily in various concentrations, ranging between 10 and 250 μL/L, in the culture medium of maize (Zea mays) plants in their early ontogenetic stages. The used static magnetic field was about 50 mT. In order to investigate the biochemical changes of chlorophylls and total carotenoids, spectrophotometric measurements were carried out, that revealed stimulatory effects of ferrofluid and magnetic exposure upon the studied plant species

  7. Phenoplant: a web resource for the exploration of large chlorophyll fluorescence image datasets

    OpenAIRE

    Rousseau, Céline; Hunault, Gilles; Gaillard, Sylvain; Bourbeillon, Julie; Montiel, Gregory; Simier, Philippe; Campion, Claire; Jacques, Marie Agnes; Belin, Etienne; Boureau, Tristan

    2015-01-01

    Background Image analysis is increasingly used in plant phenotyping. Among the various imaging techniques that can be used in plant phenotyping, chlorophyll fluorescence imaging allows imaging of the impact of biotic or abiotic stresses on leaves. Numerous chlorophyll fluorescence parameters may be measured or calculated, but only a few can produce a contrast in a given condition. Therefore, automated procedures that help screening chlorophyll fluorescence image datasets are needed, especiall...

  8. Bark and leaf chlorophyll fluorescence are linked to wood structural changes in Eucalyptus saligna

    OpenAIRE

    Johnstone, Denise; Tausz, Michael; Moore, Gregory; Nicolas, Marc

    2014-01-01

    Wood structure and wood anatomy are usually considered to be largely independent of the physiological processes that govern tree growth. This paper reports a statistical relationship between leaf and bark chlorophyll fluorescence and wood density. A relationship between leaf and bark chlorophyll fluorescence and the quantity of wood decay in a tree is also described. There was a statistically significant relationship between the leaf chlorophyll fluorescence parameter F v/F m and wood density...

  9. Fluorescent indices of oak and wheat leaves in dependence on chlorophyll content

    Science.gov (United States)

    Kalmatskaya, Olesya Ð. ń.; Karavaev, Vladimir A.; Gunar, Lyudmila E.

    2016-04-01

    Fluorescence spectra and fluorescence induction curves of the leaves of two plant species in dependence on chlorophyll content were studied. Red oak (Quercus rubra L.) leaves upon the autumn chlorophyll degradation, as well as wheat leaves (Triticum aestivum L.) at various stages of ontogenesis showed linear dependence between the ratio ω = F740 / F685 (the ratio of the maximum values of fluorescence at respective wavelengths) and chlorophyll content. In both cases, parameter Fv / Fm (the relative value of the variable fluorescence) remained almost unchanged up to significant reduction of chlorophyll content, indicating on maintaining the high photochemical activity of photosystem 2.

  10. Chlorophyll bleaching by UV-irradiation in vitro and in situ: Absorption and fluorescence studies

    International Nuclear Information System (INIS)

    Chlorophyll bleaching by UV-irradiation has been studied by absorbance and fluorescence spectroscopy in extracts containing mixtures of photosynthetic pigments, in acetone and n-hexane solutions, and in aqueous thylakoid suspensions. Chlorophyll undergoes destruction (bleaching) accompanied by fluorescent transient formation obeying first-order kinetics. The bleaching is governed by UV-photon energy input, as well as by different chlorophyll molecular organizations in solvents of different polarities (in vitro), and in thylakoids (in situ). UV-C-induced bleaching of chlorophylls in thylakoids is probably caused by different mechanisms compared to UV-A- and UV-B-induced bleaching

  11. Ocean color spectral variability studies using solar-induced chlorophyll fluorescence

    Science.gov (United States)

    Hoge, Frank E.; Swift, Robert N.

    1987-01-01

    It is suggested that chlorophyll-induced ocean color spectral variability can be studied using only a passive airborne spectroradiometer instrument, with solar-induced chlorophyll fluorescence used as the standard against which all correlations are performed. The intraspectral correlation (ISC) method is demonstrated with results obtained during an airborne mapping mission in the New York Bight. The curvature algorithm is applied to the solar-induced chlorophyll fluorescence at about 690 nm, and good agreement is found with results obtained using active-passive correlation spectroscopy. The ISC method has application to spectral variability and resulting chlorophyll concentration measurement in different environmental conditions and in different water types.

  12. DUF538 protein superfamily is predicted to be chlorophyll hydrolyzing enzymes in plants.

    Science.gov (United States)

    Gholizadeh, Ashraf

    2016-01-01

    The possible hydrolytic activity towards chlorophyll molecules was predicted for DUF538 protein superfamily in plants. It was examined by using computational as well as experimental tools including in vitro chlorophyll degradation, antioxidant compounds production and in vivo real-time gene expression tests. Comparison of the computational data with the experimental results indicated that DUF538 proteins might be chlorophyll hydrolyzing enzyme (most probably carboxyesterase) which degrade chlorophyll molecules (66 % per 12 hrs) to produce new compounds (1.8 fold per 12 hrs) with antioxidant properties. The relevance of DUF538 gene expression level with the chlorophyll contents (2.8 fold increase per chlorophyll content of 50 %) of the drought-stressed leaves showed that chlorophyll degradation by DUF538 is most probably induced in response to stress stimuli. Despite membranous chlorophyll catabolic pathways, DUF538-dependent reactions is predicted to be occurred in the cytosol of the under stressed plants. We addressed as to whether chlorophyll breakdown to antioxidant compounds by DUF538 is a defense mechanism of plants against stress stimuli, in vivo? This question is going to be investigated in our next research project. PMID:27186021

  13. Effect of gamma radiation on chlorophylls contents, net photosynthesis and respiration of chlorella pyrenoidosa

    International Nuclear Information System (INIS)

    The effect of five doses of gamma radiation: 10, 100, 500, 1000 and 5000 Gy on chlorophylls content, net photosynthesis and respiration of chlorella pyrenoidosa has been studied. A decrease in chlorophylls levels is produced after irradiation at 500, 1000 and 5000 Gy, being, at first 'b' chlorophyll affected to a greater extent than 'a' chlorophyll. Net photosynthesis and respiration decline throughout the time of the observations after irradiation, this depressing effect being much more remarkable for the first one. Net photosynthesis inhibition levels of about 30% have got only five hours post irradiation at a dose of 5000 Gy. (author)

  14. Rapid assessment of water pollution by airborne measurement of chlorophyll content.

    Science.gov (United States)

    Arvesen, J. C.; Weaver, E. C.; Millard, J. P.

    1971-01-01

    Present techniques of airborne chlorophyll measurement are discussed as an approach to water pollution assessment. The differential radiometer, the chlorophyll correlation radiometer, and an infrared radiometer for water temperature measurements are described as the key components of the equipment. Also covered are flight missions carried out to evaluate the capability of the chlorophyll correlation radiometer in measuring the chlorophyll content in water bodies with widely different levels of nutrients, such as fresh-water lakes of high and low eutrophic levels, marine waters of high and low productivity, and an estuary with a high sediment content. The feasibility and usefulness of these techniques are indicated.

  15. Chlorophyll as a simple, inexpensive and environment-friendly colorimetric indicator for NO2 gas

    Directory of Open Access Journals (Sweden)

    May Kristine O. Bernardo

    2014-06-01

    Full Text Available Chlorophyll is utilized as a simple, inexpensive and environment-friendly (“green” colorimetric indicator for nitrogen dioxide (NO2 gas. A drastic color change from green to yellow was observed when chlorophyll, either dissolved in CH2Cl2 solution or absorbed into paper, was exposed to NO2 gas. Other gases such as CO2 and SO2 did not exhibit any color change with chlorophyll. Spectroscopic analysis showed nitration of chlorophyll as possible cause for the color change.

  16. MES16, a member of the methylesterase protein family, specifically demethylates fluorescent chlorophyll catabolites during chlorophyll breakdown in Arabidopsis.

    Science.gov (United States)

    Christ, Bastien; Schelbert, Silvia; Aubry, Sylvain; Süssenbacher, Iris; Müller, Thomas; Kräutler, Bernhard; Hörtensteiner, Stefan

    2012-02-01

    During leaf senescence, chlorophyll (Chl) is broken down to nonfluorescent chlorophyll catabolites (NCCs). These arise from intermediary fluorescent chlorophyll catabolites (FCCs) by an acid-catalyzed isomerization inside the vacuole. The chemical structures of NCCs from Arabidopsis (Arabidopsis thaliana) indicate the presence of an enzyme activity that demethylates the C13(2)-carboxymethyl group present at the isocyclic ring of Chl. Here, we identified this activity as methylesterase family member 16 (MES16; At4g16690). During senescence, mes16 leaves exhibited a strong ultraviolet-excitable fluorescence, which resulted from large amounts of different FCCs accumulating in the mutants. As confirmed by mass spectrometry, these FCCs had an intact carboxymethyl group, which slowed down their isomerization to respective NCCs. Like a homologous protein cloned from radish (Raphanus sativus) and named pheophorbidase, MES16 catalyzed the demethylation of pheophorbide, an early intermediate of Chl breakdown, in vitro, but MES16 also demethylated an FCC. To determine the in vivo substrate of MES16, we analyzed pheophorbide a oxygenase1 (pao1), which is deficient in pheophorbide catabolism and accumulates pheophorbide in the chloroplast, and a mes16pao1 double mutant. In the pao1 background, we additionally mistargeted MES16 to the chloroplast. Normally, MES16 localizes to the cytosol, as shown by analysis of a MES16-green fluorescent protein fusion. Analysis of the accumulating pigments in these lines revealed that pheophorbide is only accessible for demethylation when MES16 is targeted to the chloroplast. Together, these data demonstrate that MES16 is an integral component of Chl breakdown in Arabidopsis and specifically demethylates Chl catabolites at the level of FCCs in the cytosol. PMID:22147518

  17. Modelling GPP and chlorophyll fluorescence using SCOPE (Invited)

    Science.gov (United States)

    van der Tol, C.; Verhoef, W.

    2009-12-01

    Chlorophyll fluorescence of Photosystem II (PSII) is a measure for photosynthetic processes and the functional state of the vegetation. Research in the past has focused on the active (light-induced) measurement of fluorescence at leaf and field scale. Current research focuses on the potential of satellite remote sensing of passive (solar-induced) chlorophyll fluorescence of PSII to monitor photosynthetic processes of terrestrial vegetation at large spatial scales. This research includes the relationship between top-of-canopy (TOC) fluorescence and gross primary production (GPP). The recently developed model SCOPE simulates this relationship using three sub-models. The first sub-model (FLUSPECT) is based on PROSPECT and describes leaf fluorescence spectra as a function of their chemical composition. The second sub-model describes the effects of leaf temperature, humidity and irradiance on these spectra and on actual photosynthesis. The third sub-model is a canopy level radiative transfer model, which calculates the scattering and absorption of solar radiation and fluorescence within a canopy, and computes the TOC spectrum of fluorescence in observation direction. A sensitivity analysis of the model shows a strong relationship between solar induced fluorescence and GPP at canopy level. This relationship is consistent with data from field campaigns. Fluorescence and GPP are sensitive to stress conditions including high leaf temperatures and water stress.

  18. Molluscicidal activity of chlorophyll extraction against the freshwater snails

    Directory of Open Access Journals (Sweden)

    Mona Said Mahmoud

    2013-09-01

    Full Text Available Objective: To evaluate the molluscicidal activity of chlorophyll extract as a photodynamic substance against the snails Lymnaea stagnalis, Biomphalaria spp. and Physa marmorata. Methods: Chlorophyllin was extracted from deep-frozen spinach. Snails were incubated in chlorophyllin containing water with 2.5, 5.0, 10.0 and 15.0 µg/mL. All samples were kept in darkness overnight for incubation. After incubation, three samples were irradiated with simulated solar radiation for 3 h. After irradiation, the vitality of the organisms was determined. Results: The photodynamically active chlorophyllin, at low concentrations, was able to kill snails within a few hours under exposure of solar radiation. Besides, it had a killing effect by about 70% and 100% on the snails’ eggs and the newly hatched snails, respectively, after 3 h exposure to solar radiation. Conclusion: The derivates of chlorophyll was a very interesting substance for photodynamic freshwater snail control. Hence, it might be a promising and cheap new strategy which probably had the potential to replace the synthetic molluscicides for snail control.

  19. Chlorophyll fluorescence analysis and imaging in plant stress and disease

    Energy Technology Data Exchange (ETDEWEB)

    Daley, P.F.

    1994-12-01

    Quantitative analysis of chlorophyll fluorescence transients and quenching has evolved rapidly in the last decade. Instrumentation capable of fluorescence detection in bright actinic light has been used in conjunction with gas exchange analysis to build an empirical foundation relating quenching parameters to photosynthetic electron transport, the state of the photoapparatus, and carbon fixation. We have developed several instruments that collect video images of chlorophyll fluorescence. Digitized versions of these images can be manipulated as numerical data arrays, supporting generation of quenching maps that represent the spatial distribution of photosynthetic activity in leaves. We have applied this technology to analysis of fluorescence quenching during application of stress hormones, herbicides, physical stresses including drought and sudden changes in humidity of the atmosphere surrounding leaves, and during stomatal oscillations in high CO{sub 2}. We describe a recently completed portable fluorescence imaging system utilizing LED illumination and a consumer-grade camcorder, that will be used in long-term, non-destructive field studies of plant virus infections.

  20. Decadal variability of chlorophyll a in the South China Sea:a possible mechanism

    Institute of Scientific and Technical Information of China (English)

    LIU Fenfen; CHEN Chuqun; ZHAN Haigang

    2012-01-01

    Four climatologies on a monthly scale (January,April,May and November) of chlorophyll a within the South China Sea (SCS) were calculated using a Coastal Zone Color Scanner (CZCS) (1979-1983) and the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) (1998-2002).We analyzed decadal variability of chlorophyll a by comparing the products of the two observation periods.The relationships of variability in chlorophyll a with sea surface wind speed (SSW),sea surface temperature (SST),wind stress (WS),and mixed layer depth (MLD) were determined.The results indicate that there is obvious chlorophyll a decadal variability in the SCS.The decadal chlorophyll a presents distinct seasonal variability in characteristics,which may be as a result of various different dynamic processes.The negative chlorophyll a concentration anomaly in January was associated with the warming of SST and a shallower MLD.Generally,there were higher chlorophyll a concentrations in spring during the SeaWiFS period compared with the CZCS period.However,the chlorophyll a concentration exhibits some regional differences during this season,leading to an explanation being difficult.The deepened MLD may have contributed to the positive chlorophyll a concentration anomalies from the northwestern Luzon Island to the northeastern region of Vietnam during April and May.The increases of chlorophyll a concentration in northwestem Borneo during May may be because the stronger SSW and higher WS produce a deeper mixed layer and convective mixing,leading to high levels of nutrient concentrations.The higher chlorophyll a off southeastem Vietnam may be associated with the advective transport of the colder water extending from the Karimata Strait to southeastem Vietnam.

  1. Contribution of Chlorophyll Fluorescence to the Apparent Reflectance of Vegetation

    Science.gov (United States)

    Campbell, P. K. Entcheva; Middleton, E. M.; Kim, M. S.

    2007-01-01

    Current strategies for monitoring the physiologic status of terrestrial vegetation rely on remote sensing reflectance (R) measurements, whi ch provide estimates of relative vegetation vigor based primarily on chlorophyll content. Vegetation chlorophyll fluorescence (CF) offers a non-destructive alternative and a more direct approach for diagnosis of vegetation stress before a significant reduction in chlorophyll content has occurred. Thus, monitoring of vegetation vigor based on CF may allow earlier stress detection and more accurate carbon sequestra tion estimates, than is possible using R data alone. However, the observed apparent vegetation reflectance (Ra) in reality includes contrib utions from both the reflected and fluoresced radiation. The aim of t his study is to determine the relative R and CF fractions contributing to Ra from the vegetation in the red to near-infrared region of the spectrum. The practical objectives of the study are to: 1) evaluate t he relationship between CF and R at the foliar level for corn, soybean, maple; and 2) for corn, determine if the relationship established f or healthy (optimal N) vegetation changes under N defiiency. To obtai n generally applicable results, experimental measurements were conducted on unrelated crop and tree species (maple, soybean and corn), unde r controlled conditions and a gradient of inorganic N fertilization l evels. Optical R spectra and actively induced CF emissions were obtained on the same foliar samples, in conjunction with measurements of p hotosynthetic function, pigment levels, and C and N content. The comm on spectral trends or similarities were examined. On average, 10-20% of apparent R at 685 nm was actually due to CF. The spectral trends in steady and maximum F varied significantly, with Fs (especially red) showing higher ability for species and treatment separation. The relative contribution of ChF to R varied significantly among species, with maple emitting much higher F amounts, as

  2. Contribution of chlorophyll fluorescence to the apparent vegetation reflectance

    International Nuclear Information System (INIS)

    Current strategies for monitoring the physiologic status of terrestrial vegetation rely on remote sensing reflectance data, which provide estimates of vigor based primarily on chlorophyll content. Chlorophyll fluorescence (ChlF) measurements offer a non-destructive alternative and a more direct approach for diagnosis of vegetation stress before a significant reduction in chlorophyll content has occurred. Thus, technology based on ChlF may allow more accurate carbon sequestration estimates and earlier stress detection than is possible when using reflectance data alone. However, the observed apparent vegetation reflectance (Ra) in reality includes contributions from both the reflected and fluoresced radiation. The aim of this study is to determine the relative contributions of reflectance and ChlF fractions to Ra in the red to near-infrared region (650-800 nm) of the spectrum. The practical objectives of the study are to: 1) evaluate the relationship between ChlF and reflectance at the foliar level for corn, soybean and maple; and 2) for corn, determine if the relationship established for healthy vegetation changes under nitrogen (N) deficiency. To obtain generally applicable results, experimental measurements were conducted on unrelated crop and tree species (corn, soybean and maple) under controlled conditions and a gradient of inorganic N fertilization levels. Optical reflectance spectra and actively induced ChlF emissions were collected on the same foliar samples, in conjunction with measurements of photosynthetic function, pigment levels, and carbon (C) and N content. The spectral trends were examined for similarities. On average, 10-20% of Ra at 685 nm was actually due to ChlF. The spectral trends in steady state and maximum fluorescence varied significantly, with steady state fluorescence (especially red, 685 nm) showing higher ability for species and treatment separation. The relative contribution of ChlF to Ra varied significantly among species, with maple

  3. Photoprotective Energy Dissipation in Higher Plants Involves Alteration of the Excited State Energy of the Emitting Chlorophyll(s) in the Light Harvesting Antenna II (LHCII)*

    OpenAIRE

    Johnson, Matthew P.; Ruban, Alexander V.

    2009-01-01

    Non-photochemical quenching (NPQ), a mechanism of energy dissipation in higher plants protects photosystem II (PSII) reaction centers from damage by excess light. NPQ involves a reduction in the chlorophyll excited state lifetime in the PSII harvesting antenna (LHCII) by a quencher. Yet, little is known about the effect of the quencher on chlorophyll excited state energy and dynamics. Application of picosecond time-resolved fluorescence spectroscopy demonstrated that NPQ involves a red-shift ...

  4. Study of 660 nm laser-induced photoluminescence of chlorophyll-a and its applications

    International Nuclear Information System (INIS)

    Based on the phenomenon of chlorophyll a photoluminescence, this paper introduces a new method to measure the chlorophyll a content, using 660nm laser diode as a new kind of light source to stimulate fluorescence as well as combining a fiber and spectrum technique. We analyze the characteristics of laser-induced fluorescence spectrum of chlorophyll a and then put forward the new method using two parameters, the relative fluorescence intensity and fluorescence intensity ratio F685/F735, to measure the chlorophyll a content in the water and green leaves respectively. The experimental results indicate that it is completely feasible to give a visual judgment for chlorophyll a content, according to the fluorescence emission spectrum of chlorophyll a. Subsequently, it is verified by three kinds of typical applications. All of these provide a new kind of light source to develop the chlorophyll a fluorometry and further give a technical foundation of on-spot monitoring the chlorophyll a content in the ocean or in green leaves

  5. From chlorophyll a towards bacteriochlorophyll a: Excited-state processes of modified pigments

    OpenAIRE

    Teuchner, K.; Stiel, H.; Leupold, D; Katheder, Ingrid; Scheer, Hugo

    1994-01-01

    By means of fluorescence spectroscopy and nonlinear absorption experiments, excited-state processes of the modified pigments [3-acetyl]-chlorophyll a, [31-OH]-bacteriochlorophyll a and [3-vinyl]-bacteriochlorophyll a were investigated and compared with those of chlorophyll a and bacteriochlorophyll a.

  6. TOXICITY OF INDUSTRIAL EFFLUENT ON TOTAL CHLOROPHYLL CONTENT OF CERTAIN AQUATIC MACROPHYTES

    Directory of Open Access Journals (Sweden)

    Singh Priti

    2012-04-01

    Full Text Available To assess the toxicity of industrial effluents on certain macrophytes, the total chlorophyll content of free floating, submerged and emergent macrophytes were estimated in concentrations of industrial effluents at varying exposure duration. The result revealed reduction in total chlorophyll content of exposed macrophytes at higher concentrations of industrial effluents on prolonged duration.

  7. TOXICITY OF INDUSTRIAL EFFLUENT ON TOTAL CHLOROPHYLL CONTENT OF CERTAIN AQUATIC MACROPHYTES

    OpenAIRE

    Singh Priti; Vishen Ashish; Wadhwani R; Pandey Y.N

    2012-01-01

    To assess the toxicity of industrial effluents on certain macrophytes, the total chlorophyll content of free floating, submerged and emergent macrophytes were estimated in concentrations of industrial effluents at varying exposure duration. The result revealed reduction in total chlorophyll content of exposed macrophytes at higher concentrations of industrial effluents on prolonged duration.

  8. Nondestructive and intuitive determination of circadian chlorophyll rhythms in soybean leaves using multispectral imaging

    Science.gov (United States)

    Pan, Wen-Juan; Wang, Xia; Deng, Yong-Ren; Li, Jia-Hang; Chen, Wei; Chiang, John Y.; Yang, Jian-Bo; Zheng, Lei

    2015-06-01

    The circadian clock, synchronized by daily cyclic environmental cues, regulates diverse aspects of plant growth and development and increases plant fitness. Even though much is known regarding the molecular mechanism of circadian clock, it remains challenging to quantify the temporal variation of major photosynthesis products as well as their metabolic output in higher plants in a real-time, nondestructive and intuitive manner. In order to reveal the spatial-temporal scenarios of photosynthesis and yield formation regulated by circadian clock, multispectral imaging technique has been employed for nondestructive determination of circadian chlorophyll rhythms in soybean leaves. By utilizing partial least square regression analysis, the determination coefficients R2, 0.9483 for chlorophyll a and 0.8906 for chlorophyll b, were reached, respectively. The predicted chlorophyll contents extracted from multispectral data showed an approximately 24-h rhythm which could be entrained by external light conditions, consistent with the chlorophyll contents measured by chemical analyses. Visualization of chlorophyll map in each pixel offers an effective way to analyse spatial-temporal distribution of chlorophyll. Our results revealed the potentiality of multispectral imaging as a feasible nondestructive universal assay for examining clock function and robustness, as well as monitoring chlorophyll a and b and other biochemical components in plants.

  9. The molecular photophysics of chlorophyl : a study of its triplet state

    NARCIS (Netherlands)

    Kleibeuker, J.F.

    1977-01-01

    The lowest excited triplet state T 0 of chlorophyll a , chlorophyll b , bacteriochlorophyll and corresponding pheophytins has been studied by magnetic resonance and optical spectroscopy. Zero field splitting (US) parameters D and E, populating rates, a

  10. Strong enhancement of chlorophyll a concentration by a weak typhoon

    CERN Document Server

    SUN, Liang; Xian, Tao; Lu, Zhu-min; Fu, Yun-Fei; 10.3354/meps08477

    2010-01-01

    Recent studies demonstrate that chlorophyll a (chl a) concentrations in the surface ocean can be significantly enhanced due to typhoons. The present study investigated chl a concentrations in the middle of the South China Sea (SCS) from 1997-2007. Only the Category1 (minimal) Typhoon Hagibis (2007) had a notable effect on the chl a concentrations. Typhoon Hagibis had a strong upwelling potential due to its location near the equator, and the forcing time of the typhoon (>82 h) was much longer than the geostrophic adjustment time (~63 h). The higher upwelling velocity and the longer forcing time increased the depth of the mixed-layer, which consequently induced a strong phytoplankton bloom that accounted for about 30% of the total annual chl a concentration in the middle of the SCS. The implication is that the forcing time of a typhoon should be long enough to establish a strong upwelling and consequently for the induction of significant upper ocean responses.

  11. Contribution of Chlorophyll Fluorescence to the Reflectance of Corn Foliage

    Science.gov (United States)

    Campbell, Petya K. Entcheva; Middleton, Elizabeth M.; Corp, L. A.; McMurtrey, J. E.; Kim, M. S.; Chappelle, E. W.; Butcher, L. M.; Ranson, K. Jon (Technical Monitor)

    2002-01-01

    To assess the contribution of chlorophyll fluorescence (ChlF) to apparent reflectance (Ra) in the red/far-red, spectra were collected on a C4 agricultural species (corn, Zea Mays L.) under conditions ranging from nitrogen deficiency to excess. A significant contribution of ChlF to Ra was observed, with on average 10-25% at 685nm and 2-6% at 740nm of Ra being due to ChlF. Higher ChlF was consistently measured from the abaxial leaf surface as compared to the adaxial. Using 350-665nm excitation, the study confirms the trends in three ChlF ratios established previously by active F technology, suggesting that the ChlF utility this technology has developed for monitoring vegetation physiological status is likely applicable also under natural solar illumination.

  12. Quenching of chlorophyll fluorescence induced by silver nanoparticles.

    Science.gov (United States)

    Queiroz, A M; Mezacasa, A V; Graciano, D E; Falco, W F; M'Peko, J-C; Guimarães, F E G; Lawson, T; Colbeck, I; Oliveira, S L; Caires, A R L

    2016-11-01

    The interaction between chlorophyll (Chl) and silver nanoparticles (AgNPs) was evaluated by analyzing the optical behavior of Chl molecules surrounded by different concentrations of AgNPs (10, 60, and 100nm of diameter). UV-Vis absorption, steady state and time-resolved fluorescence measurements were performed for Chl in the presence and absence of these nanoparticles. AgNPs strongly suppressed the Chl fluorescence intensity at 678nm. The Stern-Volmer constant (KSV) showed that fluorescence suppression is driven by the dynamic quenching process. In particular, KSV was nanoparticle size-dependent with an exponential decrease as a function of the nanoparticle diameter. Finally, changes in the Chl fluorescence lifetime in the presence of nanoparticles demonstrated that the fluorescence quenching may be induced by the excited electron transfer from the Chl molecules to the metal nanoparticles. PMID:27280858

  13. Chlorophyll fluorescence control in microalgae by biogenic guanine crystals

    Science.gov (United States)

    Miyashita, Yuito; Iwasaka, Masakazu; Endo, Hirotoshi

    2015-05-01

    Magnetic fields were applied to water suspensions of guanine crystals to induce changes in light scattering as a possible way to control photosynthesis in microalgae. The effect of guanine microcrystals with and without an applied magnetic field on the photosynthesis of a unicellular microalgae (plant), Pleurochrysis. carterae (P. carterae), was investigated by examining chlorophyll fluorescence. The fluorescence intensity at 600-700 nm of the photosynthetic cells increased remarkably when the concentration ratio of guanine microcrystals was 10 times larger than that of the cells. This increase in fluorescence occurred reproducibly and was proportional to the amount of guanine microcrystals added. It is speculated that the guanine microcrystals enhance the intensity of the excitation light on the cells by concentrating the excitation light or prolonging the time of light exposure to the cells. Moreover, applying a 500-mT magnetic field allowed modulation of the fluorescence intensity, depending on the direction of the fluorescence light.

  14. Canopy Level Chlorophyll Fluorescence and the PRI in a Cornfield

    Science.gov (United States)

    Middleton, Elizabeth M.; Cheng, Yen-Ben; Corp, Lawrence A.; Campbell, Petya K. E.; Huemmrich, K. Fred; Zhang, Qingyuan; Kustas, William P.

    2012-01-01

    Two bio-indicators, the Photochemical Reflectance Index (PRI) and solar-induced red and far-red Chlorophyll Fluorescence (SIF), were derived from directional hyperspectral observations and studied in a cornfield on two contrasting days in the growing season. Both red and far-red SIF exhibited higher values on the day when the canopy in the early senescent stage, but only the far-red SIF showed sensitivity to viewing geometry. Consequently, the red/far-red SIF ratio varied greatly among azimuth positions while the largest values were obtained for the "hotspot" at both growth stages. This ratio was lower (approx.0.88 +/- 0.4) in early July than in August when the ratio approached equivalence (near approx.1). In concert, the PRI exhibited stronger responses to both zenith and azimuth angles and different values on the two growth stages. The potential of using these indices to monitor photosynthetic activities needs further investigation

  15. Laser and sunlight-induced fluorescence from chlorophyll pigments

    Science.gov (United States)

    Kim, H. H.; Brown, K. S.

    1986-01-01

    Fluorescence properties of chlorophyll pigment bearing plant foliage utilizing a 337 nm nitrogen laser and integrating sphere were studied. Measured yields, in terms of number of photons emitted per 100 photons absorbed, range from 1.5 to 0.1 for the 685 nm peak, and from 4.2 to 0.2 for the 730 nm peak. Decreasing order of magnitude puts herbaceous leaves ahead of all others followed by broad leaves of hardwoods and coniferous needles. Meaningful quantization for the fluorescence peaks at 430 and 530 nm could not be attained. Passive monitoring of these fluorescence peaks is successful only for the 685 nm from the ocean surface. Field data show the reflectance changes at 685 nm due to the algae presence amounts to 1% at most.

  16. Chlorophyll meter for estimating nitrogen status of irrigated wheat

    International Nuclear Information System (INIS)

    Chlorophyll-meter readings, generated from the leaves of irrigated wheat at particular growth stages, were normalized to the data obtained with locally recommended rates of fertilizer N, in Chile China, India and Mexico. Normalizing permitted comparisons of crop-N status across growth stages, locations, cultivars, and years. Relative yields and meter readings at growth-stage Z-50 are presented; they revealed similar trends for India, China, and Chile, however, for Mexico, the combination of soil, wheat cultivar, and climate resulted in much less response to N fertilization in the meter data. The implications are discussed. The SPAD meter proved to be a good tool to monitor and evaluate the N status of irrigated wheat. (author)

  17. Chlorophyll mediated photodynamic inactivation of blue laser on Streptococcus mutans

    Science.gov (United States)

    Astuti, Suryani Dyah; Zaidan, A.; Setiawati, Ernie Maduratna; Suhariningsih

    2016-03-01

    Photodynamic inactivation is an inactivation method in microbial pathogens that utilize light and photosensitizer. This study was conducted to investigate photodynamic inactivation effects of low intensity laser exposure with various dose energy on Streptococcus mutans bacteria. The photodynamic inactivation was achieved with the addition of chlorophyll as photosensitizers. To determine the survival percentage of Streptococcus mutans bacteria after laser exposure, the total plate count method was used. For this study, the wavelength of the laser is 405 nm and variables of energy doses are 1.44, 2.87, 4.31, 5.74, 7.18, and 8.61 in J/cm2. The results show that exposure to laser with energy dose of 7.18 J/cm2 has the best photodynamic inactivation with a decrease of 78% in Streptococcus

  18. Study on the Correlation Between Chlorophyll Maximum and Remote Sensing Data

    Institute of Scientific and Technical Information of China (English)

    XIU Peng; LIU Yuguang

    2006-01-01

    Based on the in situ optical measurements in the Bohai Sea of China, which belongs to a typical case-2 water area, we studied the characteristics of DCM (deep chlorophyll maximum) such as its spatial distribution, vertical profile,etc.We found that when the depth of the chlorophyll maximum is comparatively small, even in turbid coastal water regions,there is always a good correlation between the concentrations of chlorophyll maximum and the satellite-received signals in blue-green spectral bands; the correlation is even better than that between the surface chlorophyll concentrations and the satellite-received signals.The strong correlation existing even in turbid coastal water regions indicates that an ocean color model to retrieve the concentration of DCM can be constructed for coastal waters if a comprehensive knowledge of the vertical distribution of chlorophyll concentration in the Bohai Sea of China is available.

  19. Thermocline Regulated Seasonal Evolution of Surface Chlorophyll in the Gulf of Aden

    KAUST Repository

    Hoteit, Ibrahim

    2015-04-01

    The Gulf of Aden, although subject to seasonally reversing monsoonal winds, has been previously reported as an oligotrophic basin during summer, with elevated chlorophyll concentrations only occurring during winter due to convective mixing. However, the Sea-Viewing Wide Field-of-View Sensor (SeaWiFS) ocean color data reveal that the Gulf of Aden also exhibits a prominent summer chlorophyll bloom and sustains elevated chlorophyll concentrations throughout the fall, and is a biophysical province distinct from the adjacent Arabian Sea. Climatological hydrographic data suggest that the thermocline, hence the nutricline, in the entire gulf is markedly shoaled by the southwest monsoon during summer and fall. Under this condition, cyclonic eddies in the gulf can effectively pump deep nutrients to the surface layer and lead to the chlorophyll bloom in late summer, and, after the transition to the northeast monsoon in fall, coastal upwelling driven by the northeasterly winds produces a pronounced increase in surface chlorophyll concentrations along the Somali coast.

  20. The effect of storage temperature of cucumber fruit on chlorophyll fluorescence

    Directory of Open Access Journals (Sweden)

    Ryszard Kosson

    2013-12-01

    Full Text Available The effect of three storage temperature levels: 12,5°C, 20°C, and 1,5°C on basic indexes of chlorophyll fluorescence of cucumber fruits was studied. The greenhouse grown cucumber fruits cv. Wiktor F1 were stored in perforated polyethylene bags or without packages. The minimum chlorophyll fluorescence (Fo, maximum chlorophyll fluorescence (Fm, variable chlorophyll fluorescence (Fv and relative variable fluorescence (Fv/Fm of the cucumber peel were measured. Relative variable fluorescence was decTeasing when cucumbers were stored at temperature lower or higher than optimum level. The chlorophyll fluorescence measurements can be helpful for determination of appropriate temperature parameters of cucumber storage.

  1. Coherence and population dynamics of chlorophyll excitations in FCP complex: Two-dimensional spectroscopy study

    International Nuclear Information System (INIS)

    Energy transfer processes and coherent phenomena in the fucoxanthin–chlorophyll protein complex, which is responsible for the light harvesting function in marine algae diatoms, were investigated at 77 K by using two-dimensional electronic spectroscopy. Experiments performed on femtosecond and picosecond timescales led to separation of spectral dynamics, witnessing evolutions of coherence and population states of the system in the spectral region of Qy transitions of chlorophylls a and c. Analysis of the coherence dynamics allowed us to identify chlorophyll (Chl) a and fucoxanthin intramolecular vibrations dominating over the first few picoseconds. Closer inspection of the spectral region of the Qy transition of Chl c revealed previously not identified, mutually non-interacting chlorophyll c states participating in femtosecond or picosecond energy transfer to the Chl a molecules. Consideration of separated coherent and incoherent dynamics allowed us to hypothesize the vibrations-assisted coherent energy transfer between Chl c and Chl a and the overall spatial arrangement of chlorophyll molecules

  2. Genetic dissection of chlorophyll content at different growth stages in common wheat

    Indian Academy of Sciences (India)

    Kunpu Zhang; Zhijun Fang; Yan Liang; Jichun Tian

    2009-08-01

    Quantitative trait loci (QTLs) for chlorophyll content were studied using a doubled haploid (DH) population with 168 progeny lines, derived from a cross between two elite Chinese wheat cultivars Huapei 3 × Yumai 57. Chlorophyll content was evaluated at the maximum tillering stage (MS), the heading stage (HS), and the grain filling stage (GS), at three different environments in 2005 and 2006 cropping seasons. QTL analyses were performed using a mixed linear model approach. A total of 17 additive QTLs and nine pairs of epistatic QTLs were detected. Ten of 17 additive QTLs for chlorophyll content were persistently expressed at more than two growth stages, which suggest developmentally regulated loci controlling genetics for chlorophyll content in different growth stages in wheat. One novel major QTL for chlorophyll content was closely linked with the PCR marker Xwmc215 and was persistently expressed at three growth stages.

  3. Chlorophyll Extraction from Microalgae: A Review on the Process Engineering Aspects

    Directory of Open Access Journals (Sweden)

    Aris Hosikian

    2010-01-01

    Full Text Available Chlorophyll is an essential compound in many everyday products. It is used not only as an additive in pharmaceutical and cosmetic products but also as a natural food colouring agent. Additionally, it has antioxidant and antimutagenic properties. This review discusses the process engineering of chlorophyll extraction from microalgae. Different chlorophyll extraction methods and chlorophyll purification techniques are evaluated. Our preliminary analysis suggests supercritical fluid extraction to be superior to organic solvent extraction. When compared to spectroscopic technique, high performance liquid chromatography was shown to be more accurate and sensitive for chlorophyll analysis. Finally, through CO2 capture and wastewater treatment, microalgae cultivation process was shown to have strong potential for mitigation of environmental impacts.

  4. Inversion of chlorophyll contents by use of hyperspectral CHRIS data based on radiative transfer model

    International Nuclear Information System (INIS)

    Chlorophyll content, the most important pigment related to photosynthesis, is the key parameter for vegetation growth. The continuous spectrum characteristics of ground objects can be captured through hyperspectral remotely sensed data. In this study, based on the coniferous forest radiative transfer model, chlorophyll contents were inverted by use of hyperspectral CHRIS data in the coniferous forest coverage of Changbai Mountain Area. In addition, the sensitivity of LIBERTY model was analyzed. The experimental results validated that the reflectance simulation of different chlorophyll contents was coincided with that of the field measurement, and hyperspectral vegetation indices applied to the quantitative inversion of chlorophyll contents was feasible and accurate. This study presents a reasonable method of chlorophyll inversion for the coniferous forest, promotes the inversion precision, is of significance in coniferous forest monitoring

  5. Interpreting chlorophyll fluorescence signals: the effects of leaf age

    Science.gov (United States)

    Albert, L.; Vergeli, P.; Martins, G.; Saleska, S. R.; Huxman, T. E.

    2015-12-01

    Remote sensing of sun-induced chlorophyll fluorescence (SIF) promises robust estimation of carbon uptake across landscapes, as studies of plant physiology have shown that fluorescence emission is directly linked to photosynthesis at the leaf level. Yet most leaf-level studies demonstrating the link between chlorophyll fluorescence and photosynthesis have studied leaves in their prime: leaves that recently finished expansion and have yet to senesce. By contrast, remote sensing of landscapes involves observing leaves of different ages. For example, broadleaf deciduous forests and annual plant communities in temperate regions have leaves that develop and then senesce over the course of a growing season. In this experiment, we explored how leaf age and moisture availability affect steady-state fluoresence (Fs) at the leaf level. We simultaneously measured net photosynthesis (Anet) and Fs for leaves of known ages on greenhouse-grown dwarf Helianthus Annuus (sunflowers) from two watering treatments. To monitor plant water status, we measured pre-dawn water potential, and, for a subset of leaves, osmotic potential. Fully expanded or near-fully expanded leaves (~8 to ~23 days old) had higher Anet at saturating light than young, expanding leaves (less than 8 days old) or old leaves nearing senescence (>23 days old). We found a positive relationship between Fs and Anet, suggesting that the link between fluorescence emission and photosynthesis is robust across leaves of different ages. However, leaf age had marked effects on the light response curve of photosynthesis and fluorescence metrics. These results suggest that leaf age distribution, and changes in leaf age distribution due to phenology, should be considered when interpreting SIF at the landscape level.

  6. Chlorophyll fluorescence of the testa of Brassica oleracea seeds as an indicator of seed maturity and seed quality

    OpenAIRE

    Jalink H.; Frandas A.; Schoor R. van der; Bino J.B.

    1998-01-01

    Chlorophyll fluorescence of the testa of seeds is proposed as a non-invasive method for the determination of maturity and quality of seeds. In this study cabbage seeds (Brassica oleracea) were sorted individually based on the chlorophyll fluorescence signals into four subsamples labeled with respect to their chlorophyll fluorescence signal (low, medium, high and very high). The results show that the magnitude of the chlorophyll fluorescence signal was inversely related to the quality of the s...

  7. Differential effects of glyphosate and aminomethylphosphonic acid (AMPA) on photosynthesis and chlorophyll metabolism in willow plants.

    Science.gov (United States)

    Gomes, Marcelo Pedrosa; Le Manac'h, Sarah Gingras; Maccario, Sophie; Labrecque, Michel; Lucotte, Marc; Juneau, Philippe

    2016-06-01

    We used a willow species (Salix miyabeana cultivar SX64) to examine the differential secondary-effects of glyphosate and aminomethylphosphonic acid (AMPA), the principal glyphosate by-product, on chlorophyll metabolism and photosynthesis. Willow plants were treated with different concentrations of glyphosate (equivalent to 0, 1.4, 2.1 and 2.8kgha(-1)) and AMPA (equivalent to 0, 0.28, 1.4 and 2.8kgha(-1)) and evaluations of pigment contents, chlorophyll fluorescence, and oxidative stress markers (hydrogen peroxide content and antioxidant enzyme activities) in leaves were performed after 12h of exposure. We observed that AMPA and glyphosate trigger different mechanisms leading to decreases in chlorophyll content and photosynthesis rates in willow plants. Both chemicals induced ROS accumulation in willow leaves although only glyphosate-induced oxidative damage through lipid peroxidation. By disturbing chlorophyll biosynthesis, AMPA induced decreases in chlorophyll contents, with consequent effects on photosynthesis. With glyphosate, ROS increases were higher than the ROS-sensitive threshold, provoking chlorophyll degradation (as seen by pheophytin accumulation) and invariable decreases in photosynthesis. Peroxide accumulation in both AMPA and glyphosate-treated plants was due to the inhibition of antioxidant enzyme activities. The different effects of glyphosate on chlorophyll contents and photosynthesis as described in the literature may be due to various glyphosate:AMPA ratios in those plants. PMID:27155486

  8. Cyanobacterial chlorophyll as a sensitizer for colloidal TiO 2

    Science.gov (United States)

    Kathiravan, A.; Chandramohan, M.; Renganathan, R.; Sekar, S.

    2009-01-01

    Chlorophyll has been extracted from cyanobacteria. The adsorption of chlorophyll on the surface of colloidal TiO 2 through electrostatic interaction was observed. The apparent association constant ( Kapp) of chlorophyll-TiO 2 obtained from absorption spectra is 3.78 × 10 4 M -1. The Kapp value of chlorophyll-TiO 2 as determined from fluorescence spectra is 1.81 × 10 4 M -1, which matches well with that determined from the absorption spectra changes. These data indicate that there is an interaction between chlorophyll and colloidal TiO 2 nanoparticle surface. The dynamics of photoinduced electron transfer from chlorophyll to the conduction band of colloidal TiO 2 nanoparticle has been observed and the mechanism of electron transfer has been confirmed by the calculation of free energy change (Δ Get) by applying Rehm-Weller equation as well as energy level diagram. Lifetime measurements gave the rate constant ( ket) for electron injection from the excited state chlorophyll into the conduction band of TiO 2 is 4.2 × 10 8 s -1.

  9. Efficiency of chlorophyll in gross primary productivity: A proof of concept and application in crops.

    Science.gov (United States)

    Gitelson, Anatoly A; Peng, Yi; Viña, Andrés; Arkebauer, Timothy; Schepers, James S

    2016-08-20

    One of the main factors affecting vegetation productivity is absorbed light, which is largely governed by chlorophyll. In this paper, we introduce the concept of chlorophyll efficiency, representing the amount of gross primary production per unit of canopy chlorophyll content (Chl) and incident PAR. We analyzed chlorophyll efficiency in two contrasting crops (soybean and maize). Given that they have different photosynthetic pathways (C3 vs. C4), leaf structures (dicot vs. monocot) and canopy architectures (a heliotrophic leaf angle distribution vs. a spherical leaf angle distribution), they cover a large spectrum of biophysical conditions. Our results show that chlorophyll efficiency in primary productivity is highly variable and responds to various physiological and phenological conditions, and water availability. Since Chl is accessible through non-destructive, remotely sensed techniques, the use of chlorophyll efficiency for modeling and monitoring plant optimization patterns is practical at different scales (e.g., leaf, canopy) and under widely-varying environmental conditions. Through this analysis, we directly related a functional characteristic, gross primary production with a structural characteristic, canopy chlorophyll content. Understanding the efficiency of the structural characteristic is of great interest as it allows explaining functional components of the plant system. PMID:27374843

  10. Production of Liquid Chlorophyll from The Leaves of Green Grass Jelly (Premna oblongifolia Merr.

    Directory of Open Access Journals (Sweden)

    Novelina Novelina

    2015-01-01

    Full Text Available Chlorophyll is known to be used as a natural dye. The last few years it is known that chlorophyll has an important role as a source of antioxidants that are good for health. The availability of sources of chlorophyll in Indonesia is very large, one of which is the green grass jelly leaves (Premna obliongifolia Merr. The research objective is to get grass jelly leaf extract as a source of chlorophyll and know the characteristics of the resulting extract chlorophyll. The process of extraction is done by maceration with ethanol and addition of 7% NaHCO3. The yield of the concentrated extract obtained was 35% -36%. Concentrated extract of leaves of grass jelly contains the highest levels of total chlorophyll 1184.475 mg / L. The antioxidant activity of IC 50 (ppm is 6533.9. Likewise, the results of toxicity tests is known that chlorophyll extract treatment response inactive with LC50> 1000 mg / mL is 1170.5 to 1504.8 mg / mL.

  11. Orientation of chlorophylls within chloroplasts as shown by optical and electrochromic properties of the photosynthetic membrane.

    Science.gov (United States)

    Paillotin, G; Breton, J

    1977-04-01

    The effects on the optical properties of photosynthetic membranes caused by several types of chlorophyll differing in resonance frequency and in spatial disposition are theoretically analyzed. Using a method of moments and the linear dichroism spectrum of the lamellae, we evaluated the mean angle (phi) between the transition moment of each chlorophyll and the normal to the lamellae. We have confirmed that at about 695 nm the transition moment is in the plane of the lamellae, and outside it for chlorophyll b (phi approximately 48.6 degrees). By integrating over frequency the absorption variations affected by ionophores, we show that they may be ascribed to a Stark effect, and we analyze the dependence of this effect on the orientation of the chlorophylls. From this dependence and the degree of polarization of the Stark effect, we calculate the spatial fluctuations of the angle phi. The calculation shows that a definite value of phi corresponds to each resonance frequency of chlorophyl a found in vivo. This proves that the chlorophylls a are not oriented partly random. For chlorophylls b, on the other hand, phi may fluctuate by some 10 degrees about its mean value. The structural consequences of these results are discussed. PMID:851575

  12. Inversion of a radiative transfer model for estimation of rice chlorophyll content using support vector machine

    Science.gov (United States)

    Lv, Jie; Yan, Zhenguo; Wei, Jingyi

    2014-11-01

    Accurate retrieval of crop chlorophyll content is of great importance for crop growth monitoring, crop stress situations, and the crop yield estimation. This study focused on retrieval of rice chlorophyll content from data through radiative transfer model inversion. A field campaign was carried out in September 2009 in the farmland of ChangChun, Jinlin province, China. A different set of 10 sites of the same species were used in 2009 for validation of methodologies. Reflectance of rice was collected using ASD field spectrometer for the solar reflective wavelengths (350-2500 nm), chlorophyll content of rice was measured by SPAD-502 chlorophyll meter. Each sample sites was recorded with a Global Position System (GPS).Firstly, the PROSPECT radiative transfer model was inverted using support vector machine in order to link rice spectrum and the corresponding chlorophyll content. Secondly, genetic algorithms were adopted to select parameters of support vector machine, then support vector machine was trained the training data set, in order to establish leaf chlorophyll content estimation model. Thirdly, a validation data set was established based on hyperspectral data, and the leaf chlorophyll content estimation model was applied to the validation data set to estimate leaf chlorophyll content of rice in the research area. Finally, the outcome of the inversion was evaluated using the calculated R2 and RMSE values with the field measurements. The results of the study highlight the significance of support vector machine in estimating leaf chlorophyll content of rice. Future research will concentrated on the view of the definition of satellite images and the selection of the best measurement configuration for accurate estimation of rice characteristics.

  13. Correlation of electronic carotenoid-chlorophyll interactions and fluorescence quenching with the aggregation of native LHC II and chlorophyll deficient mutants

    International Nuclear Information System (INIS)

    The aggregation dependent correlation between fluorescence quenching and the electronic carotenoid-chlorophyll interactions, φCouplingCar S1-Chl, as measured by comparing chlorophyll fluorescence observed after two- and one-photon excitation, has been investigated using native LHC II samples as well as mutants lacking Chl 2 and Chl 13. For native LHC II the same linear correlation between φCouplingCar S1-Chl and the fluorescence quenching was observed as previously reported for the pH and Zea-dependent quenching of LHC II . In order to elucidate which carotenoid-chlorophyll pair might dominate this correlation we also investigated the mutants lacking Chl 2 and Chl 13. However, also with these mutants the same linear correlation as for native LHC II was observed. This provides indication that these two chlorophylls play only a minor role for the observed effects. Nevertheless, we also conclude that this does not exclude that their neighboured carotenoids, lutein 1 and neoxanthin, might interact electronically with other chlorophylls close by.

  14. Detection of Fluorescence from Single Chlorophyll a Molecules Absorbed on Glass Surface

    Institute of Scientific and Technical Information of China (English)

    JI Dong-Mei; HUANG Zheng-Xi; XIA An-Dong

    2005-01-01

    @@ We investigate the single molecule spectroscopy of chlorophyll a molecules on glass surface in N2-saturated environment. The basic photodynamic parameters of chlorophyll a molecules, such as fluorescence lifetime,survival time before photobleaching, on-time, and off-time, are reported. A four-level model is employed to describe the possible dynamics and photobleaching of chlorophyll a upon excitation. Broad distributions in fluorescence lifetimes and survival times are mainly due to the heterogeneities of both molecular conformation and local environment.

  15. Relationship between the Water Body Chlorophyll-a and Water Quality Factors of Wetlands Baiguishan Reservoir

    Institute of Scientific and Technical Information of China (English)

    SHE Oiu-sheng; TIAN Xun; WANG Guo-zhen; JI Xiao-cun; LI Jiu-xuan; ZHAO Zhen

    2011-01-01

    [ Objective] The aim was to explore the relationship between water body Chlorophyll-a and water quality factors of wetlands Baiguishan reservoir. [ Method] Chlorophyll-a and water quality factors of water quality of Wetlands BaiGuishan Reservoir was studied, the analysis of the relationship on water quality of Wetlands Baiguishan Reservoir was made by use of trophic status indices and SPSS17.0 statistical analysis.[ Result] Total phosphorus was an irnportant factor of influence Chlorophyll-a in reservoir, water body had slight eutrophication phenomenon in reservoir of July to October in 2010. [ Conclusion] Comprehensive management should be strengthened so as to improve the water quality of Baiguishan wetland.

  16. Studies on induction of chlorophyll mutations in soybean, Glycine max (L.) Merrill

    Institute of Scientific and Technical Information of China (English)

    Mudasir Hafiz KHAN; Sunil Dutt TYAGI

    2009-01-01

    The phenotypic response of two soybean cultivars to a chemical mutagen (ethyl methane sulphonate, EMS), physical mutagen (gamma rays) and their combinations were studied in M1 and M2 generations and the frequency and spectrum of chlorophyll mutations were worked out. Combined treatment was found to be more effective in inducing chlorophyll mutations compared to individual treatments of gamma rays and EMS in both the cultivars. As far as the spectrum of chlorophyll mutations is concerned, a wider spectrum in both the cultivars was observed in 45 kR + 0.2% EMS combined treatment.

  17. Impact of petrochemicals on the photosynthesis of Halophila ovalis using chlorophyll fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Ralph, P.J.; Burchett, M.D. [University of Sydney (Australia). Institute for Coastal Resource Management and Dept. of of Environmental Biology and Horticulture

    1998-06-01

    Laboratory-cultured Halophila ovalis showed tolerance to petrochemical exposure up to 1% (w/v) solution of Bass Strait crude oil, an oil dispersant (Corexit 9527) and a mixture of crude oil and dispersant. Quantum yield, as measured by chlorophyll fluorescence, was the most sensitive measure of the photosynthetic processes affected by petrochemical. The results indicated clearly that chlorophyll fluorescence was effective at monitoring the onset and development of stress and recovery of H. ovalis when exposed to crude oil, dispersant and a mixture of the two compounds. Photosynthetic pigment content generally confirmed the chlorophyll fluorescence response; however, several anomalies occurred. (author)

  18. Impact of petrochemicals on the photosynthesis of Halophila ovalis using chlorophyll fluorescence

    International Nuclear Information System (INIS)

    Laboratory-cultured Halophila ovalis showed tolerance to petrochemical exposure up to 1% (w/v) solution of Bass Strait crude oil, an oil dispersant (Corexit 9527) and a mixture of crude oil and dispersant. Quantum yield, as measured by chlorophyll fluorescence, was the most sensitive measure of the photosynthetic processes affected by petrochemical. The results indicated clearly that chlorophyll fluorescence was effective at monitoring the onset and development of stress and recovery of H. ovalis when exposed to crude oil, dispersant and a mixture of the two compounds. Photosynthetic pigment content generally confirmed the chlorophyll fluorescence response; however, several anomalies occurred. (author)

  19. Chlorophyll fluorescence in vivo as a probe for rapid measurement of tolerance to ultraviolet radiation

    International Nuclear Information System (INIS)

    Chlorophyll fluorescence in vivo was progressively lost in pea leaves irradiated with either short or long-wave light. The changes were consistent with the development in the intact leaves of an inhibitory site on the photooxidizing side of photosystem II. In contrast, leaves of two species of Agave, plants regarded as more resistant to UV radiation, showed only minor changes in chlorophyll fluorescence. Agave americana was affected less than A. attenuata. The application of measurements of chlorophyll fluorescence in vivo to screening for tolerance to UV radiation is discussed. (author)

  20. Time-resolved interaction investigations of carbocyanine dyes and chlorophyll a in solution

    International Nuclear Information System (INIS)

    Using a Nd:YAG laser/streak camera system of 30 ps time resolution the quenching of the fluorescence of the carbocyanine dye ICC by chlorophyll a in methanolic solution was investigated. The fluorescence lifetime of ICC decreased within the chlorophyll concentration range 0 - 9x10-5 mol/l from 170 ps to 135 ps. The observed very effective fluorescence quenching process suggests that the formation of heteroaggregates from ICC and chlorophyll is responsible for the rapid energy transfer. (author)

  1. chlorophyll autofluorescence in globular and heart-shaped embryos of some dicotyledons

    Directory of Open Access Journals (Sweden)

    B. Fyk

    2014-02-01

    Full Text Available The regions in early embryos of several species display chlorophyll autofluorescence in a certain order. First, autofluorescence in Pisum sativum appears in the basal part of globular embryos; in Lathyrus vernus in the basal part of early heart embryos; in Cardamine pratensis at the sides of the hypocotyl or in Phaseolus vulgaris in the hypocotyl of elongating heart-shaped embryos. Chlorophyll autofluorescence in an embryo proper of Pisum coincides with the development of a lamellar system in the plastids. The suspensorial plastids remain undifferentiated with one or two DNA positive nucleoids. Cardamine, Lathyrus, Phaseolus and Pisum suspensors give no chlorophyll autofluorescence.

  2. On extreme atmospheric and marine nitrogen fluxes and chlorophyll-a levels in the Kattegat Strait

    DEFF Research Database (Denmark)

    Hasager, C.B.; Carstensen, J.; Ellermann, T.; Gustafson, B.G.; Hertel, O.; Johnsson, M.; Markager, S.; Skjøth, C.A.

    2003-01-01

    A retrospective analysis is carried out to investigate the importance of the vertical fluxes of nitrogen to the marine sea surface layer in which high chlorophyll a levels may cause blooms of harmful algae and subsequent turn over and oxygen depletion at the bottom of the sea. Typically nitrogen ...... buoy observations from an experimental period in the Kattegat Strait. It is recommended to sample in-situ chlorophyll observation collocated in time to the satellite overpasses of e. g. SeaWiFS and ENVISAT MERIS to ensure improved mapping of the chlorophyll levels in the Danish waters....

  3. Influence of frequent magnetic field on chlorophyll content in leaves of sugar beet plants

    International Nuclear Information System (INIS)

    Chlorophyll content in plant leaves is correlated with the yield and nitrogen content in plants. Non-destructive investigations of chlorophyll content in leaves of 3 varieties of sugar beet grown from seeds revealed that a low frequent magnetic field, acting independently or in combination with other methods of seed improvement, increased chlorophyll content in leaves of the investigated plants. The treatment with the magnetic field increased nitrogen content in the examined plants. The effect was not connected with environmental conditions during vegetation seasons. (author)

  4. Chlorophyll a reconstruction from in situ measurements: 2. Marked carbon uptake decrease in the last century

    OpenAIRE

    Fründt, B.; Dippner, J.W.; Schulz-Bull, D. E.; Joanna J Waniek

    2015-01-01

    A chlorophyll a hindcast in the Madeira Basin from 1871 to 2008 was used to analyze the long-term variability in the oligotrophic, subtropical gyres in relation to the climate change of the last century. The deep chlorophyll maximum (DCM), as dominant pattern of the chlorophyll a field, showed a fast decrease in its strength in the 1940s. An absolute minimum was reached between 1967 and 1973 when no DCM established with a recovering to the end of the time series. Long-term variability of the ...

  5. Influence of deuterated solvents on the chlorophyll-carotene system

    International Nuclear Information System (INIS)

    Absorption, fluorescence and circular dichroism spectra of chlorophyll a (chl-a) and (chl-a + #betta#-carotene (#betta#-car)) mixture in nondeuterated and deuterated solvents (C6D6, CDCl3, CH3OD, CD3COCD3) were measured. Significant differences between absorption spectra of chl-a and (chl-a + #betta#-car) mixture in deuterated and nondeuterated solvents were observed. The dark decomposition (changes of the absorption and fluorescence intensity, spectral width and the wavelength of the absorption and fluorescence maxima during the time of storage in dark after preparation) of chl-a in deuterated solvents is quicker than that in nondeuterated ones and strongly depends on the kind of solvent. The most pronounced changes of chl-a absorption spectrum can be observed in a case of deuterated acetone (CD3COCD3). The differential circular dichroism spectra of the chl-a, #betta#-car and (chl-a + #betta#-car) mixture in different kind of nondeuterated and deuterated solvents differ in the experimental error only. Results on effect of deuterated solvents on photosynthetic pigments can be of value when comparing the data of the different spectroscopic methods with that of nuclear magnetic resonance. (author)

  6. Electron transfer reactions involving porphyrins and chlorophyll a

    International Nuclear Information System (INIS)

    Electron transfer reactions involving porphyrins (P) and quinones (Q) have been studied by pulse radiolysis. The porphyrins used were tetraphenylporphyrin (H2TPP), its tetracarboxy derivative (H2TCPP), the sodium and zinc compounds (Na2TPP and ZnTPP), and chlorophyll a (Chl a). These compounds were found to be rapidly reduced by electron transfer from (CH3)2CO-. Reduction by (CH3)2COH was rapid in aqueous solutions but relatively slow in i-PrOH solutions. Transient spectra of the anion radicals were determined and, in the case of H2TCPP-., a pK = 9.7 was derived for its protonation. Electron-transfer reactions from the anion radical of H2TCPP to benzoquinone, duroquinone, 9,10-anthraquinone 2-sulfonate, and methylviologen occur in aqueous solutions with rate constants approx. 107-109 M-1 s-1 which depend on the pH and the quinone reduction potential. Reactions of Na2TPP-., ZnTPP-., and Chl a-. with anthraquinone in basic i-PrOH solutions occur with rate constants approx. 109 M-1 s-1. The spectral changes associated with these electron-transfer reactions as observed over a period of approx. 1 ms indicated, in some cases, the formation of an intermediate complex [P...Q-.]. 8 figures, 2 tables

  7. Chloroplast ultrastructure in leaves of Cucumis sativus chlorophyll mutant

    Directory of Open Access Journals (Sweden)

    Irena Palczewska

    2014-02-01

    Full Text Available The developing and young leaves of Cucumis sativus chlorophyll mutants are yellow, when mature they become green and do not differ in their colour from those of control plants. The mesophyll of yellow leaves contains a diversiform plastid population with a varying degree of defectiveness, which is mainly manifested in the reduction or disorganization of the typical thylakoid system. DNA areas, ribosome-like particles and aggregates of electron-dense material are preserved in the stroma of mutated plastids. Starch grains are deficient. Apart from mutated plastids, chloroplasts with a normal structure, as in control plants, were also observed.The leaf greening process is accompanied by a reconstruction and rearrangement of the inner chloroplast lamellar system and an ability to accumulate starch. However, in the mutant chloroplasts as compared with control-plant ones, an irregular arrangement of grana and reduced number of inter-grana thylakoids can be seen. An osmiophilic substance stored in the stroma of mutated plastids and the vesicles formed from an internal plastid membrane take part in restoration of the membrane system.

  8. Nanotubes of Biomimetic Supramolecules Constructed by Synthetic Metal Chlorophyll Derivatives.

    Science.gov (United States)

    Shoji, Sunao; Ogawa, Tetsuya; Hashishin, Takeshi; Ogasawara, Shin; Watanabe, Hiroaki; Usami, Hisanao; Tamiaki, Hitoshi

    2016-06-01

    Various supramolecular nanotubes have recently been built up by lipids, peptides, and other organic molecules. Major light-harvesting (LH) antenna systems in a filamentous anoxygenic phototroph, Chloroflexus (Cfl.) aurantiacus, are called chlorosomes and contain photofunctional single-wall supramolecular nanotubes with approximately 5 nm in their diameter. Chlorosomal supramolecular nanotubes of Cfl. aurantiacus are constructed by a large amount of bacteriochlorophyll(BChl)-c molecules. Such a pigment self-assembles in a chlorosome without any assistance from the peptides, which is in sharp contrast to the other natural photosynthetic LH antennas. To mimic chlorosomal supramolecular nanotubes, synthetic models were prepared by the modification of naturally occurring chlorophyll(Chl)-a molecule. Metal complexes (magnesium, zinc, and cadmium) of the Chl derivative were synthesized as models of natural chlorosomal BChls. These metal Chl derivatives self-assembled in hydrophobic environments, and their supramolecules were analyzed by spectroscopic and microscopic techniques. Cryo-transmission electron microscopic images showed that the zinc and cadmium Chl derivatives could form single-wall supramolecular nanotubes and their outer and inner diameters were approximately 5 and 3 nm, respectively. Atomic force microscopic images suggested that the magnesium Chl derivative formed similar nanotubes to those of the corresponding zinc and cadmium complexes. Three chlorosomal single-wall supramolecular nanotubes of the metal Chl derivatives were prepared in the solid state and would be useful as photofunctional materials. PMID:27172060

  9. Coherence and population dynamics of chlorophyll excitations in FCP complex: Two-dimensional spectroscopy study

    CERN Document Server

    Butkus, Vytautas; Augulis, Ramūnas; Gall, Andrew; Büchel, Claudia; Robert, Bruno; Zigmantas, Donatas; Valkunas, Leonas; Abramavicius, Darius

    2015-01-01

    The energy transfer processes and coherent phenomena in the fucoxanthin-chlorophyll protein complex, which is responsible for the light harvesting function in marine algae diatoms, were investigated at 77 K by using two-dimensional electronic spectroscopy. Experiments performed on the femtosecond and picosecond timescales led to separation of spectral dynamics, witnessing evolutions of coherence and population states of the system in the spectral region of ${\\rm Q}_{y}$ transitions of chlorophylls $a$ and $c$. Analysis of the coherence dynamics allowed us to identify chlorophyll (Chl) $a$ and fucoxanthin intramolecular vibrations dominating over the first few picoseconds. Closer inspection of the spectral region of the ${\\rm Q}_{y}$ transition of Chl $c$ revealed previously not identified mutually non-interacting chlorophyll $c$ states participating in femtosecond or picosecond energy transfer to the Chl $a$ molecules. Consideration of separated coherent and incoherent dynamics allowed us to hypothesize the v...

  10. Five Year Mean Surface Chlorophyll Estimates in the Northern Gulf of Mexico for 2005 through 2009

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These images were created by combining the mean surface chlorophyll estimates to produce seasonal representations for winter, spring, summer and fall. Winter...

  11. Phytoplankton production and chlorophyll distribution in the eastarn and central Arabian Sea in 1994-1995

    Digital Repository Service at National Institute of Oceanography (India)

    Bhattathiri, P.M.A.; Pant, A.; Sawant, S.S.; Gauns, M.; Matondkar, S.G.P.; Mahanraju, R.

    Measurements of primary production, chlorophyll a, particulate organic carbon (POC) and nitrogen (PON) were carried out during the inter-monsoon winter monsoon and summer monsoon seasons of 1994-95 in the central and eastern Arabian Sea...

  12. Chlorophyll 'a' particulate organic carbon and suspended load from the mangrove areas of Cochin backwaters

    Digital Repository Service at National Institute of Oceanography (India)

    Sheeba, P.; Devi, K.S.; Balasubramanian, T.; Sankaranarayanan, V.N.

    Chlorophyll 'a' Particulate Organic Carbon and suspended load were estimated for one year from two distinct mangrove areas of Cochin backwaters, viz. Puthuvypeen and Nettoor. Environmental parameters like tau degrees C, S ppt and pH were also...

  13. Chlorophyll Detection and Mapping of Shallow Water Impoundments Using Image Spectrometry

    International Nuclear Information System (INIS)

    There exists a common perception that chlorophyll a concentrations in tidal coastal waters are unsuitable to be captured by remote sensing techniques because of high water turbidity. In this study, we use band index measurements to separate active chlorophyll pigments from other constituents in the water. Published single- and multiband spectral indices are used to establish a relationship between algal chlorophyll concentration and reflectance data. We find an index which is suitable to map chlorophyll gradients in the impoundments, ditches, and associated waterways of the Hackensack Meadow lands (NJ, USA). The resulting images clearly depict the spatial distribution of plant pigments and their relationship with the biological conditions of the waters in the estuary. Since these biological conditions are often determined by land usage, the methods in this paper provide a simple tool to address water quality management issues in fragmented urban estuaries.

  14. Chlorophyll-a, Aqua MODIS, NPP, 0.0125 degrees, East US, EXPERIMENTAL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA CoastWatch distributes chlorophyll-a concentration data from NASA's Aqua Spacecraft. Measurements are gathered by the Moderate Resolution Imaging...

  15. TRACKING CHANGES IN CHLOROPHYLL AND CAROTENOIDS IN THE PRODUCTION PROCESS OF FROZEN SPINACH PURÉE

    Directory of Open Access Journals (Sweden)

    Andrea Mendelová

    2014-02-01

    Full Text Available Spinach is in the professional and general public considered highly nutritious vegetable with many beneficial effects on human health. It is a rich source of antioxidant active substances, especially chlorophyll, carotenoids, flavonoids and minerals especially zinc and copper. This work studies the changes of chlorophyll and carotenoids that occur after mass production technology of freezing at -37 °C. Before freezing was used blanching operation. In this work we used a variety Boeing, Boa, Beaver, Hudson and Chica. The highest content of all monitored parameters are found in fresh leaves of sampled Hudson. We found that within the processing decreases chlorophyll in 16.6%, 13.8% of chlorophyll b and carotenoids of 6.15%. This decrease was in all cases statistically significant.

  16. Chlorophyll-a, Aqua MODIS, OSU DB, 0.0125 degrees, West US

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA CoastWatch distributes chlorophyll-a concentration data from NASA's Aqua satellite. Measurements are gathered by the Moderate Resolution Imaging...

  17. Chlorophyll-a, Aqua MODIS, NPP, 0.025 degrees, Pacific Ocean, EXPERIMENTAL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA CoastWatch distributes chlorophyll-a concentration data from NASA's Aqua Spacecraft. Measurements are gathered by the Moderate Resolution Imaging...

  18. Subsurface chlorophyll maxima in the north-western Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Sarma, V.V.; Aswanikumar, V.

    of thermocline suggests that the formation of the subsurface maximum is influencEd. by the presence of seasonal thermocline. Further the subsurface chlorophyll maximum is noticed within the depth ranges of ammonium maximum and nitracline, suggesting...

  19. Effect of gamma radiation on chlorophylls content, net photosynthesis and respiration of Chlorella pyrenoidosa

    International Nuclear Information System (INIS)

    The effect of five doses of gamma radiation: 10, 100, 500, 1000 and 5000 Gy on chlorophylls content, net photosynthesis and respiration of Chlorella pyrenoidosa has been studied. A decrease in chlorophylls levels is produced after irradiation at 500, 1000 and 5000 Gy, being, at first b chlorophyll affected to a greater extent than a chlorophyll. Net photosynthesis and respiration decline throughout the time of the observation after irradiation, this depressing effect being much more remarkable for the first one. Met photosynthesis inhibition levels of about 30% are got only five hours post irradiation at a dose of 5000 Gy. Radio estimation by low doses, although obtained in some cases for tho 10 Gy dose, has not been statistically confirmed. (Author) 23 refs

  20. Chlorophyll-a, Terra MODIS, OSU DB, 0.0125 degrees, West US, EXPERIMENTAL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA CoastWatch distributes chlorophyll-a concentration data from NASA's Terra satellite. Measurements are gathered by the Moderate Resolution Imaging...

  1. Chlorophyll-a, Aqua MODIS, NPP, 0.0125 degrees, Indonesia

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA CoastWatch distributes chlorophyll-a concentration data from NASA's Aqua Spacecraft. Measurements are gathered by the Moderate Resolution Imaging...

  2. Chlorophyll catalyse the photo-transformation of carcinogenic benzo[a]pyrene in water

    Science.gov (United States)

    Luo, Lijuan; Lai, Xueying; Chen, Baowei; Lin, Li; Fang, Ling; Tam, Nora F. Y.; Luan, Tiangang

    2015-08-01

    Algal blooms cause great damage to water quality and aquaculture. However, this study showed that dead algal cells and chlorophyll could accelerate the photo-transformation of benzo[a]pyrene (BaP), a ubiquitous and persistent pollutant with potently mutagenic and carcinogenic toxicities, under visible light irradiation. Chlorophyll was found to be the major active substance in dead algal cells, and generated a high level of singlet oxygen to catalyse the photo-transformation of BaP. According to various BaP metabolites formed, the degradation mechanism was proposed as that chlorophyll in dead algal cells photo-oxidized BaP to quinones via photocatalytic generation of singlet oxygen. The results provided a good insight into the role of chlorophyll in the photo-transformation of organic contaminants and could be a possible remediation strategy of organic pollutants in natural environment.

  3. Chlorophyll-a, Aqua MODIS, NPP, 0.0125 degrees, Gulf of Mexico, EXPERIMENTAL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA CoastWatch distributes chlorophyll-a concentration data from NASA's Aqua Spacecraft. Measurements are gathered by the Moderate Resolution Imaging...

  4. Two-photon excited fluorescence from higher electronic states of chlorophylls in photosynthetic antenna complexes: a new approach to detect strong excitonic chlorophyll a/b coupling.

    OpenAIRE

    Leupold, Dieter; Teuchner, Klaus; Ehlert, Jürgen; Irrgang, Klaus-Dieter; Renger, Gernot; Lokstein, Heiko

    2002-01-01

    Stepwise two-photon excitation of chlorophyll a and b in the higher plant main light-harvesting complex (LHC II) and the minor complex CP29 (as well as in organic solution) with 100-fs pulses in the Q(y) region results in a weak blue fluorescence. The dependence of the spectral shape of the blue fluorescence on excitation wavelength offers a new approach to elucidate the long-standing problem of the origin of spectral "chlorophyll forms" in pigment-protein complexes, in particular the charact...

  5. Quantitative trait loci analysis of chlorophyll content for flag leaf in rice

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    @@Chlorophyll contents are one of important physiological traits, which affect photosynthesis in plants. There were significant differences in chlorophyll contents between Zhaiyeqing 8(ZYQ 8), an indica variety and Jingxi 17(JX 17), a japonica variety (Table 1). In 117 DH lines of the cross of ZYQ 8/ JX 17, these parameters distributed conTwo neutral alleles of improving male gamete abortion in indica-japonica hybrid rice LU Chuangen and ZOU Jiangshi, Jiangsu Acad of Agri Sci, Nanjing 210014, China

  6. Effects of different cytokinins on chlorophyll retention in the moss Bryum argenteum (Bryaceae)

    OpenAIRE

    SABOVLJEVIĆ, ANETA; Sabovljević, Marko; VUKOJEVIĆ, VANJA

    2010-01-01

    Background and Purpose: Cytokinins are a group of plant hormones that have an important role in plant growth and developmental processes. Chlorophyll content is an extremely important parameter in estimating the plant production level. Since bryophytes do not have such economical importance as vascular plants and their production in many ecosystems is small, they remain uninteresting for studying their chlorophyll level. The aim of this study was to compare the effect of different cytok...

  7. Evaluation of empirical and semi-analytical chlorophyll algorithms in the Ligurian and North Tyrrhenian seas

    OpenAIRE

    C. Lapucci; M. Ampolo Rella; Brandini, C.; N. Ganzin; Gozzini, B.; Maselli, F.; L. Massi; Nuccio, C. De; A. Ortolani; C. Trees

    2012-01-01

    The estimation of chlorophyll concentration in marine waters is fundamental for a number of scientific and practical purposes. Standard ocean color algorithms applicable to moderate resolution imaging spectroradiometer (MODIS) imagery, such as OC3M and MedOC3, are known to overestimate chlorophyll concentration ([CHL]) in Mediterranean oligotrophic waters. The performances of these algorithms are currently evaluated together with two relatively new algorithms, OC5 and SAM_LT, which make use o...

  8. PIXE analysis of trace elements in relation to chlorophyll concentration in Plantago ovata Forsk

    Energy Technology Data Exchange (ETDEWEB)

    Saha, Priyanka [Department of Biophysics, Molecular Biology and Bioinformatics, University of Calcutta, 92, APC Road, 700009 Kolkata (India); Sen Raychaudhuri, Sarmistha [Department of Biophysics, Molecular Biology and Bioinformatics, University of Calcutta, 92, APC Road, 700009 Kolkata (India)], E-mail: sarmistha_rc@rediffmail.com; Chakraborty, Anindita; Sudarshan, Mathummal [UGC-DAE consortium for Scientific Research, Kolkata Centre, Radiation Biology Division, 3/LB Bidhannagar, Salt Lake, 700098 Kolkata (India)

    2010-03-15

    Plantago ovata Forsk - an economically important medicinal plant - was analyzed for trace elements and chlorophyll in a study of the effects of gamma radiation on physiological responses of the seedlings. Proton-induced X-ray emission (PIXE) technique was used to quantify trace elements in unirradiated and gamma-irradiated plants at the seedling stage. The experiments revealed radiation-induced changes in the trace element and chlorophyll concentrations.

  9. Seasonal, Diurnal and Vertical Variation of Chlorophyll Fluorescence on Phyllostachys humilis in Ireland

    OpenAIRE

    Van Goethem, Davina; De Smedt, Sebastiaan; Valcke, Roland; Potters, Geert; Samson, Roeland

    2013-01-01

    In recent years, temperate bamboo species have been introduced in Europe not only as an ornamental plant, but also as a new biomass crop. To measure adaptation stress of bamboo to the climate of Western Europe, chlorophyll fluorescence was measured on a diurnal and seasonal basis in Ballyboughal, Co. Dublin, Ireland. Measurements were attained on the leaves of each node of Phyllostachys humilis. The most frequently used parameter in chlorophyll fluorescence is the photosynthetic efficiency (F...

  10. Assessment of Salt Tolerance in Pepper Using Chlorophyll Fluorescence and Mineral Compositions

    OpenAIRE

    Mohammad Reza Zare Bavani; Gholamali Peyvast; Mahmoud Ghasemnezhad; Akbar Forghani

    2016-01-01

    In this study, leaf chlorophyll fluorescence and mineral compositions was used to compare pepper (Capsicum annuum L.) cultivars response to salt stress. Twentysix pepper cultivars were exposed to salt stress (100 mM NaCl) during two weeks. Thereafter, chlorophyll fluorescence components, stress tolerance index (STI), sodium, potassium and calcium content were measured. The results showed that a significant difference has been found among pepper cultivars for all studied characteristics....

  11. Chlorophyll fluorescence emission as a reporter on cold tolerance in Arabidopsis thaliana accessions

    OpenAIRE

    Mishra, Anamika; Mishra, Kumud B; Höermiller, Imke I; Heyer, Arnd G; Nedbal, Ladislav

    2011-01-01

    Non-invasive, high-throughput screening methods are valuable tools in breeding for abiotic stress tolerance in plants. Optical signals such as chlorophyll fluorescence emission can be instrumental in developing new screening techniques. In order to examine the potential of chlorophyll fluorescence to reveal plant tolerance to low temperatures, we used a collection of nine Arabidopsis thaliana accessions and compared their fluorescence features with cold tolerance quantified by the well establ...

  12. Red and far red sun-induced chlorophyll fluorescence as a measure of plant photosynthesis

    OpenAIRE

    M. Rossini; L. Nedbal; Luis Guanter; A. Ač; L. Alonso; A. Burkart; S. Cogliati; R. Colombo; A. Damm; M. Drusch; J. Hanus; R. Janoutova; T. Julitta; P. Kokkalis; J. Moreno

    2015-01-01

    Remote estimation of Sun-induced chlorophyll fluorescence emitted by terrestrial vegetation can provide an unparalleled opportunity to track spatiotemporal variations of photosynthetic efficiency. Here we provide the first direct experimental evidence that the two peaks of the chlorophyll fluorescence spectrum can be accurately mapped from high-resolution radiance spectra and that the signal is linked to variations in actual photosynthetic efficiency. Red and far red fluorescence measured usi...

  13. Early Water Stress Detection Using Leaf-Level Measurements of Chlorophyll Fluorescence and Temperature Data

    OpenAIRE

    Zhuoya Ni; Zhigang Liu; Hongyuan Huo; Zhao-Liang Li; Françoise Nerry; Qingshan Wang; Xiaowen Li

    2015-01-01

    The purpose of this paper was to investigate the early water stress in maize using leaf-level measurements of chlorophyll fluorescence and temperature. In this study, a series of diurnal measurements, such as leaf chlorophyll fluorescence (Fs), leaf spectrum, temperature and photosynthetically active radiation (PAR), were conducted for maize during gradient watering and filled watering experiments. Fraunhofer Line Discriminator methods (FLD and 3FLD) were used to obtain fluorescence from leav...

  14. Near infrared fluorescent chlorophyll nanoscale liposomes for sentinel lymph node mapping

    Directory of Open Access Journals (Sweden)

    Fan L

    2012-06-01

    Full Text Available Lina Fan,1,* Qiang Wu,1,* Maoquan Chu1,21School of Life Science and Technology, 2The Institute for Advanced Materials and Nano Biomedicine Tongji University, Shanghai, People's Republic of China *These authors contributed equally to this workBackground: Sentinel lymph node (SLN mapping using in vivo near infrared fluorescence imaging has attracted great attention during the past few years. Here we report on the early use of poorly water-soluble chlorophyll with near infrared fluorescence extracted from the leaf of Chimonanthus salicifolius, for mouse axillary SLN mapping.Methods and results: To improve the water solubility and SLN targeting of the chlorophyll, we encapsulated the chlorophyll in nanoscale liposomes. The liposome-coated chlorophyll nanocomposites obtained were spherical in shape and had an average diameter of 21.7 ± 6.0 nm. The nanocomposites dispersed well in water, and in aqueous suspension they exhibited brighter near infrared fluorescence than chlorophyll alone. After incubation of the nanocomposites with normal liver cells (QSG-7701 and macrophage cells (Ana-1 for no more than 48 hours, there was no obvious reduction in cell viability. When the nanocomposites were injected intradermally into the paw of a mouse, the axillary SLN was found to be strongly fluorescent and was easily visualized in real time without a requirement for surgery. The intensity of the near infrared fluorescence emitted by the SLN was obviously brighter than that emitted by the SLN of another mouse that had been intradermally injected with chlorophyll alone.Conclusion: Our data show that the liposome-coated chlorophyll nanocomposites could have great potential for clinical SLN mapping due to their lack of toxicity, bright near infrared fluorescence, and small diameter.Keywords: chlorophyll, liposomes, nanocomposites, near infrared fluorescence, sentinel lymph node mapping

  15. CHLOROPHYLL AND CAROTENOID PIGMENTS IN THE PEEL AND FLESH OF COMMERCIAL APPLE FRUITS VARIETIES.

    OpenAIRE

    Delgado-Pelayo, Raúl; Gallardo Guerrero, Lourdes; Hornero-Méndez, Dámaso

    2014-01-01

    Apple (Malus x domestica Borkh) has always been considered a fruit with low chlorophyll and carotenoid contents; however these pigments contribute also to the external (peel) and internal (flesh) fruit colouration, as well as to the health benefits associated with the regular consumption of this fruit. In the present work we studied the chlorophyll and carotenoid composition of the peel and flesh of thirteen marketed apple varieties presenting different external colouration (gr...

  16. Structural Effects of Heat-Treated Silica Xerogel Induced by Incorporation of Chlorophyll Species

    OpenAIRE

    J. R. Martínez; G. Martínez-Castañón; Ortega-Zarzosa, G.; de la Cruz-Mendoza, J. A.; Facundo Ruiz; S. A. Palomares-Sánchez

    2007-01-01

    Composites containing chlorophyll aggregates dispersed in amorphous silica are of interest because of their optical attractive properties. The silica powders added with chlorophyll species, prepared by the sol-gel method, were studied using X-ray diffraction, IR spectroscopy and differential temperature analysis. Silica xerogel samples were prepared using an ethanol/H2O/TEOS molar ratio of 4:11.6:1 and loaded with extracts from frozen spinach leaves. The silica xerogel microstructure of the p...

  17. PIXE analysis of trace elements in relation to chlorophyll concentration in Plantago ovata Forsk

    International Nuclear Information System (INIS)

    Plantago ovata Forsk - an economically important medicinal plant - was analyzed for trace elements and chlorophyll in a study of the effects of gamma radiation on physiological responses of the seedlings. Proton-induced X-ray emission (PIXE) technique was used to quantify trace elements in unirradiated and gamma-irradiated plants at the seedling stage. The experiments revealed radiation-induced changes in the trace element and chlorophyll concentrations.

  18. PIXE analysis of trace elements in relation to chlorophyll concentration in Plantago ovata Forsk.

    Science.gov (United States)

    Saha, Priyanka; Raychaudhuri, Sarmistha Sen; Chakraborty, Anindita; Sudarshan, Mathummal

    2010-03-01

    Plantago ovata Forsk - an economically important medicinal plant - was analyzed for trace elements and chlorophyll in a study of the effects of gamma radiation on physiological responses of the seedlings. Proton-induced X-ray emission (PIXE) technique was used to quantify trace elements in unirradiated and gamma-irradiated plants at the seedling stage. The experiments revealed radiation-induced changes in the trace element and chlorophyll concentrations. PMID:20047839

  19. Estimation of chlorophyll-a concentration in the Zhujiang Estuary from SeaWiFS data

    Institute of Scientific and Technical Information of China (English)

    Chen Chuqun(陈楚群); Shi Ping(施平); Magnus Larson; Lennart Jonsson

    2002-01-01

    The chlorophyll-a concentration is generally overestimated for the southem China coastal waters if the default algorithm of the SeaDAS is employed. An algorithm is developed for retrieval of chlorophyll-a concentration in the Zhujiang Estuary, Guangdong Province, China, by using simulated reflectance data. The simulated reflectance is calculated corresponding to the SeaWiFS wavelength bands, via a general model by inputting measured water components, I.e., the suspended sediment,chlorophyll-a, and yellow substance (DOC) concentration data of 130 samples. Empirical relationships of the chlorophyll-a concentration to 240 different band combinations are investigated based on the simulated reflectance data, and the band combination, R5R6/R3R4, is found to be the optimum one for the development of an algorithm valid for the Zhujiang Estuary. This algorithm is then employed to determine the chlorophyll-a concentration from SeaWiFS data. The estimated concentrations have a better accuracy than those obtained from the SeaDAS default algorithm when comnpared with sea truth data. The new algorithm is demonstrated to work well and is used to derive a series of image maps of the chlorophyll-a concentration distribution for the Zhujiang Estuary and adjacent coastal areas.

  20. Genetic Analysis and Molecular Mapping of a Novel Chlorophyll-Deficit Mutant Gene in Rice

    Institute of Scientific and Technical Information of China (English)

    HUANG Xiao-qun; WANG Ping-rong; ZHAO Hai-xin; DENG Xiao-jian

    2008-01-01

    A rice etiolation mutant 824ys featured with chlorophyll deficiency was identified from a normal green rice variety 824B.It showed whole green-yellow plant from the seedling stage,reduced number of tillers and longer growth duration.The contents of chlorophyll,chlorophyll a,chlorophyll b and net photosynthetic rate in leaves of the mutant obviously decreased,as well as the number of spikelets per panicle,seed setting rate and 1000-grain weight compared with its wild-type parent.Genetic analyses on F1 and F2 generetions of 824ys crossed with three normal green varieties showed that the chlorophyll-deficit mutant character was controlled by a pair of recessive nuclear gene.Genetic mapping of the mutant gene was conducted by using microsatellite markers and F2 mapping population of 495R/824ys,and the mutant gene of 824ys was mapped on the shon arm of rice chromosome 3.The genetic distances from the target gene to the markers RM218,RM282 and RM6959 were 25.6 cM,5.2 cM and 21.8 cM,respectively.It was considered to be a now chlorophyll-deficit mutant gene and tentatively named as chl11(t).

  1. Mixed layer variability and chlorophyll a biomass in the Bay of Bengal

    Science.gov (United States)

    Narvekar, J.; Prasanna Kumar, S.

    2014-07-01

    The mixed layer is the most variable and dynamically active part of the marine environment that couples the underlying ocean to the atmosphere and plays an important role in determining the oceanic primary productivity. We examined the basin-scale processes controlling the seasonal variability of mixed layer depth in the Bay of Bengal and its association with chlorophyll using a suite of in situ as well as remote sensing data. A coupling between mixed layer depth and chlorophyll was seen during spring intermonsoon and summer monsoon, but for different reasons. In spring intermonsoon the temperature-dominated stratification and associated shallow mixed layer makes the upper waters of the Bay of Bengal nutrient depleted and oligotrophic. In summer, although the salinity-dominated stratification in the northern Bay of Bengal shallows the mixed layer, the nutrient input from adjoining rivers enhance the surface chlorophyll. This enhancement is confined only to the surface layer and with increase in depth, the chlorophyll biomass decreases rapidly due to reduction in sunlight by suspended sediment. In the south, advection of high salinity waters from the Arabian Sea and westward propagating Rossby waves from the eastern Bay of Bengal led to the formation of deep mixed layer. In contrast, in the Indo-Sri Lanka region, the shallow mixed layer and nutrient enrichment driven by upwelling and Ekman pumping resulted in chlorophyll enhancement. The mismatch between the nitrate and chlorophyll indicated the inadequacy of present data to fully unravel its coupling to mixed layer processes.

  2. On extreme atmospheric and marine nitrogen fluxes and chlorophyll-a levels in the Kattegat Strait

    DEFF Research Database (Denmark)

    Hasager, C.B.; Carstensen, J.; Ellermann, T.; Gustafson, B.G.; Hertel, O.; Johnsson, M.; Markager, S.; Skjøth, C.A.

    2003-01-01

    Strait. In the southern part, the extreme chlorophyll level is only 4 mg m(-3) according to the statistics of a multi-year time-series of water samples. The chlorophyll level varies greatly in time and space as documented by a series of SeaWiFS satellite maps (OC4v4 algorithm) of chlorophyll ScanFish and...... are calculated by the periodic maximum method and the results are successfully compared to a map of chlorophyll return periods based on in-situ observations. The one-year return of extreme atmospheric wet deposition is around 60 mg N m(-2) day(-1) and 30 mg N m(-2) day(-1) for deep-water entrainment...... buoy observations from an experimental period in the Kattegat Strait. It is recommended to sample in-situ chlorophyll observation collocated in time to the satellite overpasses of e. g. SeaWiFS and ENVISAT MERIS to ensure improved mapping of the chlorophyll levels in the Danish waters....

  3. GIS based spatial distribution of Temperature and Chlorophyll-a along Kalpakkam, southeast coast of India

    Directory of Open Access Journals (Sweden)

    Muthulakshmi.AL

    2015-05-01

    Full Text Available This paper briefly describes the status of Temperature and Chlorophyll-a trend in Kalpakkam Coast, discusses its ecological and temperature impacts recommending measures to achieve long term sustainability using advanced tools like Geographic Information System (GIS. Present study reveals the monthly spatial distribution of Temperature and Chlorophyll-a at Kalpakkam. Transect based in-situ Temperature and Chlorophyll-a collected at 200m, 500m and 1 km distance into the sea was interpolated using the Inverse Distance Weightage (IDW method in ARC GIS. Data revealed the extent of spatial distribution of thermal effluent in Kalpakkam. It could be found that temperature range of 26.2 – 31.9°C provided substantial Chlorophyll-a concentration between 0.8 – 2.9 mg/m3 for surface and bottom waters. Further, increase of Chlorophyll-a levels did not lead to higher productivity. Combined temperature and chlorophyll a showed little synergistic effects. It is concluded that the effect of thermal discharge from the power plant into the receiving water body is quite localized and productivity of the coastal waters are not affected. From the results obtained, the spatial data has been found to be useful in determining zones of safe use of seawater and to understand the extent of relationship between the relatable parameters.

  4. Chlorophyll and carbohydrates in Arachis pintoi plants under influence of water regimes and nitrogen fertilization

    Directory of Open Access Journals (Sweden)

    Rita Manuele Porto Sales

    2013-06-01

    Full Text Available In this experiment the chlorophyll and carbohydrate contents of Arachis pintoi were evaluated to verify if the presence of nitrogen in the soil could contribute to the effectiveness of the establishment of this legume. The design was completely randomized, in a 4 × 4 factorial arrangement, with four N rates (0, 40, 80 and 120 kg ha-1 and four irrigation levels (25, 50, 75 and 100% of field capacity, with four replications. The biochemical evaluations of chlorophylls a and b and total chlorophyll and total soluble sugars, sucrose and starch were performed. The highest contents of chlorophyll a and b and total chlorophyll in leaves were found at the dose of 120 kg ha-1. The water regime of 25% of field capacity was responsible for the lowest content of reducing sugars and total soluble sugars in leaves, stolons and roots. In the roots, the sucrose contents were higher in these conditions, which can be associated with a slight tolerance of the plant to water stress. The water deficiency was responsible for the decrease of reducing sugars and total N in the whole plant and positively influenced the levels of chlorophyll and sugars in the stolon, promoting growth, especially of shoots, at the beginning of establishment.

  5. Contrasting correlation patterns between environmental factors and chlorophyll levels in the global ocean

    Science.gov (United States)

    Feng, Jianfeng; Durant, Joël. Marcel; Stige, Leif Chr.; Hessen, Dag Olav; Hjermann, Dag Øystein; Zhu, Lin; Llope, Marcos; Stenseth, Nils Chr.

    2015-12-01

    In this study we analyze large-scale satellite-derived data using generalized additive models to characterize the global correlation patterns between environmental forcing and marine phytoplankton biomass. We found systematic differences in the relationships between key environmental drivers (temperature, light, and wind) and ocean chlorophyll in the subtropical/tropical and temperate oceans. For the subtropical/tropical and equatorial oceans, the chlorophyll generally declined with increasing temperature and light, while in temperate oceans, chlorophyll was best explained by bell-shaped or positive functions of temperature and light. The relationship between chlorophyll and wind speed is generally positive in low-latitude oceans and bell shaped in temperate oceans. Our analyses also demonstrated strong and geographically consistent positive autoregressive effects of chlorophyll from 1 month to the next and negative autoregressive effects for measurements 2 months apart. These findings imply possibly different regional phytoplankton responses to environmental forcing, suggesting that future environmental change could affect the tropical and temperate upper ocean chlorophyll levels differently.

  6. Effect of PEG-6000 Imposed Water Deficit on Chlorophyll Metabolism in Maize Leaves

    Directory of Open Access Journals (Sweden)

    Rekha Gadre

    2013-08-01

    Full Text Available Drought stress is one of the major abiotic constraint limiting plant growth and productivity world wide. The current study was undertaken with the aim to investigate the effect of water deficit imposed by PEG-6000, on chlorophyll metabolism in maize leaves to work out the mechanistic details. Leaf segments prepared from primary leaves of etiolated maize seedlings were treated with varying concentrations of polyethylene glycol-6000 (PEG-6000; w/v- 5%, 10%, 20%, 30% in continuous light of intensity 40 Wm-2 at 26±2 °C for 24 h in light chamber. The results demonstrate a concentration dependent decline in chlorophyll content with increasing concentration of polyethylene glycol-6000 (PEG-6000. Reduction in chlorophyll ‘a’ level was to a greater extent than the chlorophyll ‘b’. The RNA content decreased in a concentration dependent manner with PEG, however, proline content increased significantly. Relative water content decreased significantly with the supply of 30% PEG only. A substantial decrease in chlorophyll synthesis due to significant reduction in ALA content and ALAD activity, with no change in chlorophyllase activity with the supply of PEG suggests that water deficit affects chlorophyll formation rather than its degradation.

  7. Spatiotemporal Variation in Mangrove Chlorophyll Concentration Using Landsat 8

    Directory of Open Access Journals (Sweden)

    Julio Pastor-Guzman

    2015-11-01

    Full Text Available There is a need to develop indicators of mangrove condition using remotely sensed data. However, remote estimation of leaf and canopy biochemical properties and vegetation condition remains challenging. In this paper, we (i tested the performance of selected hyperspectral and broad band indices to predict chlorophyll concentration (CC on mangrove leaves and (ii showed the potential of Landsat 8 for estimation of mangrove CC at the landscape level. Relative leaf CC and leaf spectral response were measured at 12 Elementary Sampling Units (ESU distributed along the northwest coast of the Yucatan Peninsula, Mexico. Linear regression models and coefficients of determination were computed to measure the association between CC and spectral response. At leaf level, the narrow band indices with the largest correlation with CC were Vogelmann indices and the MTCI (R2 > 0.5. Indices with spectral bands around the red edge (705–753 nm were more sensitive to mangrove leaf CC. At the ESU level Landsat 8 NDVI green, which uses the green band in its formulation explained most of the variation in CC (R2 > 0.8. Accuracy assessment between estimated CC and observed CC using the leave-one-out cross-validation (LOOCV method yielded a root mean squared error (RMSE = 15 mg·cm−2, and R2 = 0.703. CC maps showing the spatiotemporal variation of CC at landscape scale were created using the linear model. Our results indicate that Landsat 8 NDVI green can be employed to estimate CC in large mangrove areas where ground networks cannot be applied, and mapping techniques based on satellite data, are necessary. Furthermore, using upcoming technologies that will include two bands around the red edge such as Sentinel 2 will improve mangrove monitoring at higher spatial and temporal resolutions.

  8. The algorithms of chlorophyll-a concentration for CMODIS

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The algorithms of extracting chlorophyll-a (Chl-a) concentration have been established for Chinese moderate resolution imaging spectrometer (CMODIS) mounted on Shenzhou-3 spaceship launched on 25 March 2002. The CMODIS is an ocean color sensor with 30 visible channels and 4 infrared channels, much different from other ocean color satellites and needs new algorithms to process data. Three models of Chl-a concentration were established based on Chl-a data retrieved from sea-viewing wide field-of-view sensor (SeaWiFS), with the average relative errors of 26.6%, 24%.0% and 33.5%, respectively. This practical and economic approach can be used for developing the algorithms of Chinese ocean color and temperature sensor (COCTS) on the satellite Haiyang-1 to derive the Chl-a concentration concentration distribution.The applicability of the algorithms was analyzed using some in situ measurements. Suspended sediment is the main factor influencing the accuracy of the spectral ratio algorithms of Chl-a concentration. The algorithms are suitable to using in the regions where suspended sediment concentrations (SSC) are less than 5 g/m3 under the condition of relative error of Chl-a concentration retrieval within 35%. High concentration of suspended sediment leads to the overestimate remote sensing retrieval of concentration of Chl-a, while low-middle SSCs lead to the low Chl-a concentration values using the spectral ratio algorithms. Since the accuracy of Chl-a concentration by the spectral ratio algorithms is limited to waters of Case 2, it is necessary to develop semi-analytical models to improve the performance of satellite ocean color remote sensing in turbid coastal waters.

  9. Analysis of quantitative trait loci underlying the traits related to chlorophyll content of the flag leaf in rice

    Institute of Scientific and Technical Information of China (English)

    Guohua YANG; Sansi TU; Shaoqing LI; Lingling FENG; Jin KONG; Hui LI; Yangsheng LI

    2008-01-01

    A population of 117 doubled haploid (DH) lines derived from the cross of Zhaiyeqing 8 (indica) x Jingxi 17 (japonica) was employed to map quantitative trait loci (QTL) underlying four physiological traits related to chlorophyll contents of the flag leaf. There were significantly positive correlations among chlorophyll a, chlorophyll b and chlorophyll a+ b content. Chlorophyll a/b ratio was significantly negatively correlated with chlorophyll b content. These four traits were normally distributed with transgressive segregation, suggesting that they were controlled by multiple minor genes. A total of 11 QTLs were detected for the four traits and they lay on six chromosomes. Each of them explained 9.2%-19.6% of the phenotypic variations, respectively. Of these, two QTLs controlling chlorophyll a content were mapped on chromosomes 2 and 5; four QTLs underlying chlorophyll b content were mapped on chromosomes 2, 3, 5 and 9; three QTLs underlying chlorophyll a+b amount were mapped on chromosomes 3, 5 and 9; two QTLs under-lying chlorophyll a/b ratio were mapped on chromosomes 6 and 1 1. The intrinsic relationship among the four traits and the practical implication in rice breeding are discussed.

  10. Effects of Chlorophyll Availability on Fluorescence Components of Photosystems in the ORF469-Deletion Mutant of Cyanobacterium

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    PCR-amplified ORF469 fragment from Synechocystis sp.PCC 6803 was cloned into pUC118 and a construct was made in which part of ORF469 was deleted and replaced by erythromycin resistance cassette.Transformation of wild type strain of Synechocystis sp.PCC 6803 with this construct yielded a mutant in which ORF469 was deleted.In the resulting mutant, the light-independent pathway of chlorophyll biosynthesis was inactivated and availability of chlorophyll was fully dependent on light.When propagated the mutant in dark, the chlorophyll was non-detectable and protochlorophyllide with 645 nm fluorescence emission peak was accumulated.Meanwhile, the fluorescence emission peaks (excited at 435 nm) of thylakoids at 685 nm, 695 nm and 725 nm, which represented relative chlorophyll-binding proteins, disappeared.Upon return of dark-grown ORF469 mutant to the light, greening occurred and chlorophyll was synthesized to assembly fluorescence emission components in photosystems.Newly synthesized chlorophyll combined the fluorescence component of 685 nm at first, then 725 nm and 695 nm at last, which indicates a pecking order for biogenesis of chlorophyll-binding proteins when availability of chlorophyll is limited.The mutant lacking ORF469 in Synechocystis sp.PCC 6803 was suggested as an excellent cyanobacterial system for studies on the interactions between chlorophyll and chlorophyll-binding proteins in photosystems.

  11. Mixed layer variability and chlorophyll a biomass in the Bay of Bengal

    Directory of Open Access Journals (Sweden)

    J. Narvekar

    2013-10-01

    Full Text Available Mixed layer is the most variable and dynamically active part of the marine environment that couples the underlying ocean to the atmosphere and plays an important role in determining the chlorophyll concentration. In this paper we examined the seasonal variability of the mixed layer depth in the Bay of Bengal, the factors responsible for it and the coupling of mixed layer processes to the chlorophyll biomass using a suite of in situ as well as remote sensing data. The basin-wide mixed layer depth was the shallowest during spring intermonsoon, which was associated with strong themohaline stratification of the upper water column. The prevailing winds which were the weakest of all the seasons were unable to break the stratification leading to the observed shallow mixed layer. Consistent with the warm oligotrophic upper ocean, the surface chlorophyll concentrations were the least and the vertical profile of chlorophyll was characterized by a subsurface chlorophyll maximum. Similarly, during summer though the monsoon winds were the strongest they were unable to break the upper ocean haline-stratification in the northern Bay brought about by a combination of excess precipitation over evaporation and fresh water influx from rivers adjoining the Bay of Bengal. Consistent with this though the nitrate concentrations were high in the northern part of the Bay, the chlorophyll concentrations were low indicating the light limitation. In contrast, in the south, advection of high salinity waters from the Arabian Sea coupled with the westward propagating Rossby waves of annual periodicity were able to decrease stability of the upper water column and the prevailing monsoon winds were able to initiate deep mixing leading to the observed deep mixed layer. The high chlorophyll concentration observed in the south resulted from the positive wind stress curl which pumped nutrient rich subsurface waters to the euphotic zone. The southward extension of the shallow mixed

  12. Long-term dynamics of chlorophyll concentration in the ocean surface layer (by space data)

    Science.gov (United States)

    Shevyrnogov, A.; Vysotskaya, G.

    To preserve the biosphere and to use it efficiently, it is necessary to gain a deep insight into the dynamics of the primary production process on our planet. Variability of chlorophyll concentration in the ocean is one of the most important components of this process. These investigations are, however, very labor-consuming, because of the difficulties related to the accessibility of the water surface and its large size. In this work long-term changes in chlorophyll concentration in the surface layer of the ocean have been analyzed on the basis of the CZCS data for 7.5 years from 1979 to 1986 and the SeaWiFS data from 1997 to 2004. It has been shown that the average chlorophyll concentration calculated in all investigated areas varies moderately. However, when analyzing spatially local trends, the areas have been detected that have significant rise and fall of chlorophyll concentrations. Some interesting features of the long-term dynamics of chlorophyll concentration have been found. The opposite directions of long-term trends (essential increase or decrease) cannot be explained only by large-scale hydrological phenomena in the ocean (currents, upwellings, etc.). The measured chlorophyll concentration results from the balance between production and destruction processes. Which process dominates is determined by various hydrophysical, hydrobiological, and climatic processes, leading to sharp rises or falls of the concentration. It is important to estimate the scale of the areas in which this or that process dominates. Therefore, the study addresses not only the dynamics of the mean value but also the dynamics of the areas in which the dominance of certain factors has led to a sharp fall or rise in chlorophyll concentration. Thus, the obtained results can be used to estimate long-term changes in the ocean biota.

  13. Predicting crappie recruitment in Ohio reservoirs with spawning stock size, larval density, and chlorophyll concentrations

    Science.gov (United States)

    Bunnell, David B.; Hale, R. Scott; Vanni, Michael J.; Stein, Roy A.

    2006-01-01

    Stock-recruit models typically use only spawning stock size as a predictor of recruitment to a fishery. In this paper, however, we used spawning stock size as well as larval density and key environmental variables to predict recruitment of white crappies Pomoxis annularis and black crappies P. nigromaculatus, a genus notorious for variable recruitment. We sampled adults and recruits from 11 Ohio reservoirs and larvae from 9 reservoirs during 1998-2001. We sampled chlorophyll as an index of reservoir productivity and obtained daily estimates of water elevation to determine the impact of hydrology on recruitment. Akaike's information criterion (AIC) revealed that Ricker and Beverton-Holt stock-recruit models that included chlorophyll best explained the variation in larval density and age-2 recruits. Specifically, spawning stock catch per effort (CPE) and chlorophyll explained 63-64% of the variation in larval density. In turn, larval density and chlorophyll explained 43-49% of the variation in age-2 recruit CPE. Finally, spawning stock CPE and chlorophyll were the best predictors of recruit CPE (i.e., 74-86%). Although larval density and recruitment increased with chlorophyll, neither was related to seasonal water elevation. Also, the AIC generally did not distinguish between Ricker and Beverton-Holt models. From these relationships, we concluded that crappie recruitment can be limited by spawning stock CPE and larval production when spawning stock sizes are low (i.e., CPE , 5 crappies/net-night). At higher levels of spawning stock sizes, spawning stock CPE and recruitment were less clearly related. To predict recruitment in Ohio reservoirs, managers should assess spawning stock CPE with trap nets and estimate chlorophyll concentrations. To increase crappie recruitment in reservoirs where recruitment is consistently poor, managers should use regulations to increase spawning stock size, which, in turn, should increase larval production and recruits to the fishery.

  14. Chlorophyll Variability in the Oligotrophic Gyres: Mechanisms, Seasonality and Trends

    Directory of Open Access Journals (Sweden)

    Sergio Romano Signorini

    2015-02-01

    Full Text Available A 16-year (1998-2013 analysis of trends and seasonal patterns was conducted for the five subtropical ocean gyres using satellite data: chlorophyll-a (Chl-a retrievals from ocean color, sea surface temperature (SST, and sea-level anomaly (SLA. Trend analysis was also performed on mixed-layer data derived from ocean model gridded temperature and salinity profiles (1998-2010. The Chl-a monthly composites were constructed from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS and Moderate-resolution Imaging Spectroradiometer (MODIS on Aqua using two different algorithms: the standard algorithm (STD that has been in use since the start of the SeaWiFS mission in 1997, and a more recently developed Ocean Color Index (OCI algorithm with improved accuracy in low Chl-a waters. Trends were obtained for all gyres using both STD and OCI algorithms, which demonstrated generally consistent results. The North Pacific, Indian Ocean, North Atlantic and South Atlantic gyres showed significant downward trends in Chl-a, while the South Pacific gyre has a much weaker upward trend with no statistical significance. Time series of satellite-derived net primary production (NPP showed downward trends for all the gyres, while all five gyres exhibited positive trends in SST and SLA. The seasonal variability of Chl-a in each gyre is tightly coupled to the variability in mixed layer depth (MLD with peak values in winter in both hemispheres when vertical mixing is more vigorous, reaching depths approaching the nutricline. On a seasonal basis, Chl-a concentrations increase when the MLD approaches or is deeper than the nutricline depth, in agreement with the concept that vertical mixing is the major driving mechanism for phytoplankton photosynthesis in the interior of the gyres. The combination of surface warming trends and biomass reduction over the 16-year period has the potential to reduce atmospheric CO2 uptake by the gyres and therefore influence the global carbon cycle.

  15. Overview of Global Monitoring of Terrestrial Chlorophyll Fluorescence from Space

    Science.gov (United States)

    Guanter, Luis; Zhang, Yongguang; Kohler, Philipp; Walther, Sophia; Frankenberg, Christian; Joiner, Joanna

    2016-01-01

    Despite the critical importance of photosynthesis for the Earth system, understanding how it is influenced by factors such as climate variability, disturbance history, and water or nutrient availability remains a challenge because of the complex interactions and the lack of GPP measurements at various temporal and spatial scales. Space observations of the sun-induced chlorophyll fluorescence (SIF) electromagnetic signal emitted by plants in the 650-850nm spectral range hold the promise of providing a new view of vegetation photosynthesis on a global basis. Global retrievals of SIF from space have recently been achieved from a number of spaceborne spectrometers originally intended for atmospheric research. Despite not having been designed for land applications, such instruments have turned out to provide the necessary spectral and radiometric sensitivity for SIF retrieval from space. The first global measurements of SIF were achieved in 2011 from spectra acquired by the Japanese GOSAT mission launched in 2009. The retrieval takes advantage of the high spectral resolution provided by GOSATs Fourier Transform Spectrometer (FTS) which allows the evaluation of the in-filling of solar Fraunhofer lines by SIF. Unfortunately, GOSAT only provides a sparse spatial sampling with individual soundings separated by several hundred kilometers. Complementary, the Global Ozone Monitoring Experiment-2 (GOME-2) instruments onboard MetOp-A and MetOp-B enable SIF retrievals since 2007 with a continuous and global spatial coverage. GOME-2 measures in the red and near-infrared (NIR) spectral regions with a spectral resolution of 0.5 nm and a pixel size of up to 40x40 km2. Most recently, another global and spatially continuous data set of SIF retrievals at 740 nm spanning the 2003-2012 time frame has been produced from ENVISATSCIAMACHY. This observational scenario has been completed by the first fluorescence data from the NASA-JPL OCO-2 mission (launched in July 2014) and the upcoming

  16. Chlorophyll fluorescence response to water and nitrogen deficit

    Science.gov (United States)

    Cendrero Mateo, Maria del Pilar

    The increasing food demand as well as the need to predict the impact of warming climate on vegetation makes it critical to find the best tools to assess crop production and carbon dioxide (CO2) exchange between the land and atmosphere. Photosynthesis is a good indicator of crop production and CO2 exchange. Chlorophyll fluorescence (ChF) is directly related to photosynthesis. ChF can be measured at leaf-scale using active techniques and at field-scales using passive techniques. The measurement principles of both techniques are different. In this study, three overarching questions about ChF were addressed: Q1) How water, nutrient and ambient light conditions determine the relationships between photosynthesis and ChF? Which is the optimum irradiance level for detecting water and nutrient deficit conditions with ChF? ; Q2) which are the limits within which active and passive techniques are comparable?; and Q3) What is the seasonal relationship between photosynthesis and ChF when nitrogen is the limiting factor? To address these questions, two main experiments were conducted: Exp1) Concurrent photosynthesis and ChF light-response curves were measured in camelina and wheat plants growing under (i) intermediate-light and (ii) high-light conditions respectively. Plant stress was induced by (i) withdrawing water, and (ii) applying different nitrogen levels; and Exp2) coincident active and passive ChF measurements were made in a wheat field under different nitrogen treatments. The results indicated ChF has a direct relationship with photosynthesis when water or nitrogen drives the relationship. This study demonstrates that the light level at which plants were grown was optimum for detecting water and nutrient deficit with ChF. Also, the results showed that for leaf-average-values, active measurements can be used to better understand the daily and seasonal behavior of passive ChF. Further, the seasonal relation between photosynthesis and ChF with nitrogen stress was not a

  17. Indian Ocean Dipole and El Nino/Southern Oscillation impacts on regional chlorophyll anomalies in the Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Currie, J.C.; Lengaigne, M.; Vialard, J.; Kaplan, D.M.; Aumont, O.; Naqvi, S.W.A.; Maury, O.

    in the supplemen- tary material of Aumont and Bopp (2006). The biogeochem- ical model has 24 compartments, which include two sizes of sinking particles and four “living” biological pools, rep- resented by two phytoplankton (nano-phytoplankton and di- atoms) and two... model levels. Chlorophyll concentrations were calculated as the sum of chlorophyll from the two phytoplankton size classes (di- atoms and nano-phytoplankton). Surface chlorophyll con- centrations (denoted by SChl; units of mg m−3) were aver- aged over...

  18. Integrated impact of tropical cyclones on sea surface chlorophyll in the North Atlantic

    Science.gov (United States)

    Hanshaw, M.N.; Lozier, M.S.; Palter, J.B.

    2008-01-01

    Past studies have shown that surface chlorophyll-a concentrations increase in the wake of hurricanes. Given the reported increase in the intensity of North Atlantic hurricanes in recent years, increasing chlorophyll-a concentrations, perhaps an indication of increasing biological productivity, would be an expected consequence. However, in order to understand the impact of variable hurricane activity on ocean biology, the magnitude of the hurricane-induced chlorophyll increase relative to other events that stir or mix the upper ocean must be assessed. This study investigates the upper ocean biological response to tropical cyclones in the North Atlantic from 1997-2005. Specifically, we quantitatively compare the anomalous chlorophyll-a concentrations created by cyclone activity to the total distribution of anomalies in the subtropical waters. We show that the cyclone-induced chlorophyll-a increase has minimal impact on the integrated biomass budget, a result that holds even when taking into consideration the lagged and asymmetrical response of ocean color. Copyright 2008 by the American Geophysical Union.

  19. Effects of lanthanum nitrate on growth and chlorophyll fluorescence characteristics of Alternanthera philoxeroides under perchlorate stress

    Institute of Scientific and Technical Information of China (English)

    谢寅峰; 蔡贤雷; 刘伟龙; 陶功胜; 陈倩; 张强

    2013-01-01

    To investigate the effects of exogenous lanthanum (La) on Alternanthera philoxeroides (Mart.) Griseb under perchlorate stress, changes in the growth and physiological parameters were investigated in solution culture experiments under controlled condi-tions. Different concentrations of La (NO3)3 were used in our study. It was shown that 0.1 and 0.5 mg/L La3+alleviated the inhibition effect of perchlorate on A. philoxeroides, including relative growth yield, dry weight of different organs, leaf area and root activity. And La3+prevented decline in the relative chlorophyll content and chlorophyll fluorescence parameters including Fv/Fm, Fv'/Fm',ΦPSI and ETR induced by perchlorate stress. Moreover, 0.5 mg/L La3+showed an optimal mitigative effect, while excess La3+(5.0 mg/L) led to synergistic effect on stress. Correlation analysis revealed a significant positive relationship between growth indexes and the chlorophyll fluorescence parameters, root activity and relative chlorophyll content (p<0.05). The results suggested that appropriate concentration of La3+could effectively alleviate growth inhibition and injury of A. philoxeroides caused by perchlorate stress, and the mitigative effect of La3+might be achieved by improving root activity, maintaining chlorophyll content and promoting photochemical efficiency of photosystem II of A. philoxeroides under perchlorate stress.

  20. Coherence and population dynamics of chlorophyll excitations in FCP complex: Two-dimensional spectroscopy study

    Energy Technology Data Exchange (ETDEWEB)

    Butkus, Vytautas; Gelzinis, Andrius; Valkunas, Leonas [Department of Theoretical Physics, Faculty of Physics, Vilnius University, Sauletekio Ave. 9-III, 10222 Vilnius (Lithuania); Center for Physical Sciences and Technology, Savanoriu Ave. 231, 02300 Vilnius (Lithuania); Augulis, Ramūnas [Center for Physical Sciences and Technology, Savanoriu Ave. 231, 02300 Vilnius (Lithuania); Gall, Andrew; Robert, Bruno [Institut de Biologie et Technologies de Saclay, Bât 532, Commissariat à l’Energie Atomique Saclay, 91191 Gif sur Yvette (France); Büchel, Claudia [Institut für Molekulare Biowissenschaften, Universität Frankfurt, Max-von-Laue-Straße 9, Frankfurt (Germany); Zigmantas, Donatas [Department of Chemical Physics, Lund University, P.O. Box 124, 22100 Lund (Sweden); Abramavicius, Darius, E-mail: darius.abramavicius@ff.vu.lt [Department of Theoretical Physics, Faculty of Physics, Vilnius University, Sauletekio Ave. 9-III, 10222 Vilnius (Lithuania)

    2015-06-07

    Energy transfer processes and coherent phenomena in the fucoxanthin–chlorophyll protein complex, which is responsible for the light harvesting function in marine algae diatoms, were investigated at 77 K by using two-dimensional electronic spectroscopy. Experiments performed on femtosecond and picosecond timescales led to separation of spectral dynamics, witnessing evolutions of coherence and population states of the system in the spectral region of Q{sub y} transitions of chlorophylls a and c. Analysis of the coherence dynamics allowed us to identify chlorophyll (Chl) a and fucoxanthin intramolecular vibrations dominating over the first few picoseconds. Closer inspection of the spectral region of the Q{sub y} transition of Chl c revealed previously not identified, mutually non-interacting chlorophyll c states participating in femtosecond or picosecond energy transfer to the Chl a molecules. Consideration of separated coherent and incoherent dynamics allowed us to hypothesize the vibrations-assisted coherent energy transfer between Chl c and Chl a and the overall spatial arrangement of chlorophyll molecules.

  1. Measuring Leaf Chlorophyll Concentration from Its Color: A Way in Monitoring Environment Change to Plantations

    CERN Document Server

    Shibghatallah, Muhammad Abdul Hakim; Suhandono, Sony; Viridi, Sparisoma; Kesuma, Teja

    2013-01-01

    Leaf colors of a plant can be used to identify stress level due to its adaptation to environmental change. For most leaves green-related colors are sourced from chlorophyll a and b. Chlorophyll concentration is normally measured using a spectrophotometer in laboratory. In some remote observation places, it is impossible to collect the leaves, preserve them, and bring them to laboratory to measure their chlorophyll content. Based on this need, measurement of chlorophyll content is observed through its color. Using CIE chromaticity diagram leaf color information in RGB is transformed into wavelength (in nm). Paddy seed with variety name IR-64 is used in observation during its vegetation stage t (age of 0-10 days). Light exposure time {\\tau} is chosen as environmental change, which normally should be about 12 hours/day, is varied (0-12 hours/day). Each day sample from different exposure time is taken, its color is recorded using HP Deskjet 1050 scanner with 1200 dpi, and its chlorophyll content is obtained from ...

  2. Relationships between nutrients and chlorophyll a concentration in the international Alma Gol Wetland, Iran

    Directory of Open Access Journals (Sweden)

    Saeed Balali

    2013-05-01

    Full Text Available This study investigated the relationships between nutrients and chlorophyll, a concentration in the International Alma Gol Wetland. Chlorophyll a is the major photosynthetic pigment in lots of phytoplanktons and has been used as a trophy index in aquatic ecosystems. Water samples were collected fortnightly from five stations in the wetland during summer and autumn. Chlorophyll-a ranged between 4.38 to 156.55 mg/m3, sulfate ranged between 138 to 190 mg/l, total alkalinity ranged between 80 to 280 mg/l, silica ranged between 3.80 to 35.00 mg/l, phosphate ranged between 0.02 to 3.70 mg/l, ammonia ranged between 0.10 to 11.90 mg/l, nitrate ranged between 0.01 to 2.75 mg/l and nitrite ranged between 0.01 to 0.39 mg/l. There was a significant correlation between chlorophyll a and nitrate, nitrite and ammonia but there was no significant correlation between chlorophyll a and silica, total alkalinity, sulfate and phosphorus.

  3. Thermocline Regulated Seasonal Evolution of Surface Chlorophyll in the Gulf of Aden

    KAUST Repository

    Yao, Fengchao

    2015-03-19

    The Gulf of Aden, although subject to seasonally reversing monsoonal winds, has been previously reported as an oligotrophic basin during summer, with elevated chlorophyll concentrations only occurring during winter due to convective mixing. However, the Sea-Viewing Wide Field-of-View Sensor (SeaWiFS) ocean color data reveal that the Gulf of Aden also exhibits a prominent summer chlorophyll bloom and sustains elevated chlorophyll concentrations throughout the fall, and is a biophysical province distinct from the adjacent Arabian Sea. Climatological hydrographic data suggest that the thermocline, hence the nutricline, in the entire gulf is markedly shoaled by the southwest monsoon during summer and fall. Under this condition, cyclonic eddies in the gulf can effectively pump deep nutrients to the surface layer and lead to the chlorophyll bloom in late summer, and, after the transition to the northeast monsoon in fall, coastal upwelling driven by the northeasterly winds produces a pronounced increase in surface chlorophyll concentrations along the Somali coast. © 2015 Yao, Hoteit.

  4. [Monitoring of the Moskva River Water Using Microbiological Parameters and Chlorophyll a Fluorescence].

    Science.gov (United States)

    Mosharova, I V; Il'inskii, V V; Matorin, D N; Mosharov, S A; Akulova, A Yu; Protopopov, F F

    2015-01-01

    The results of investigations of three Moskva River sites with different degree of pollution using a complex of microbiological characteristics and the parameters of chlorophyll a fluorescence are presented. We determined that the bacterioplankton seasonal dynamics at less polluted waters (Tushino and Vorobyovy Gory) were similar and differed significantly from one in more polluted waters (Dzerzhinskii). The number of bacteria with active electron transport chain, as well as their share in the bacterioplankton structure, was higher in the water of Dzerzhinskii (average annual values of 0.23 x 10(6) cells/mL and 14%), that in the less polluted water of Tushino and Vorobyovy Gory (0.14 x 10(6) cells/mL; 6% and 0.15 x 10(6) cells/mL; 7%, respectively). From April to October, the content of chlorophyll a and its photosynthetic activity were the highest in Tushino. In Dzerzhinskii, during spring the increase in photosynthetic activity commenced earlier and was more intensive that the increase in chlorophyll a content, i.e., the increase in phytoplankton biomass was temporarily suppressed. We suggest association of this phenomenon with suppression of organic matter synthesis by phytoplankton due to the high water pollution in Dzerzhinskii. The second autumn peak of chlorophyll a content, that was typical of clear water and was observed in Tushino, did not occur in Dzerzhinskii. We recommend combined application of these microbiological parameters and characteristics of chlorophyll a fluorescence for a monitoring. PMID:26964361

  5. Seasonal variability of seasurface chlorophyll-a of waters around Sri Lanka

    Indian Academy of Sciences (India)

    Kanthi K A S Yapa

    2000-12-01

    Remotely sensed data on ocean colour of waters surrounding Sri Lanka received from the Coastal Zone Colour Scanner (CZCS) are processed and analyzed. Raw data of 1 km resolution on relatively cloud free days during 1978-1986 are processed to produce sea surface chlorophyll maps within latitudes 4.5N-11N and longitudes 78E-85E, a region in the Indian Ocean surrounding Sri Lanka. The processed data include about 110 single day maps and composite averages for each month and season. The months of July, August and September are omitted in the calculation of averages due to insufficient data. The waters in the Gulf of Mannar and Palk Bay areas show high chlorophyll-a concentrations throughout the year. However, these high values may represent other suspended particles and dissolved organic matter besides chlorophyll-a as this region is shallow (< 100 m). Regions with high chlorophyll concentrations (>0:5 mg m-3) along the coast and western ocean region can be seen in the months of October and November, after the southwest monsoon period. As high surface chlorophyll concentrations may indicate high productivity, these regions need extensive measurements of primary production and also continuous monitoring of fish catches, during and after the southwest monsoon. Studies of particle composition in shallow water areas, in particular waters in Palk Bay and Gulf of Mannar, should be carried out in order to elucidate the effect of non-phytogenic.

  6. On the calibration of large-scale fluorometric chlorophyll measurements from towed undulating vehicles

    Science.gov (United States)

    Strass, Volker

    1990-03-01

    Calibrating in situ fluorescence profiles to give the concentration of chlorophyll a at high resolution on the oceanic gyre scale must take into account large variations of fluorescence yield R (the ratio of the fluorescence signal and the chlorophyll concentration within the fluorometer detection volume). The calibration method suggested in this paper has been developed to handle fluorescence measurements made from a towed undulating vehicle along a section about 2000 km long between the Azores and Greenland repeated during the years 1984-1986. The calibration is based on equally spaced samples with photometrically determined near-surface chlorophyll concentrations and incorporates profiles of solar irradiance as auxillary variable. Judging from the auto-correlation function of R, the large variations of fluorescence yield are well resolved by the time interval of 4 h (corresponding to a horizontal distance of about 65 km) between adjacent chlorophyll samples. Using a filter based on the auto-correlation function the variability of yield is smoothed; the smoothed yield function is employed to calibrate the fluoresence signal continuously, in which yield between supporting points is interpreted linearly. Significant correlations of R with solar irradiance appear to be negative; this ambient-light-dependent fluorescence quenching is eliminated during calibration. The relative error in the chlorophyll concentration derived in this way is estimated to be 4% near the surface and 15% deeper down. The suggested calibration method is as accurate as more expensive procedures involving bottle cast series.

  7. The control of chlorophyll catabolism and the status of yellowing as a biomarker of leaf senescence.

    Science.gov (United States)

    Ougham, H; Hörtensteiner, S; Armstead, I; Donnison, I; King, I; Thomas, H; Mur, L

    2008-09-01

    The pathway of chlorophyll catabolism during leaf senescence is known in a fair amount of biochemical and cell biological detail. In the last few years, genes encoding a number of the catabolic enzymes have been characterized, including the key ring-opening activities, phaeophorbide a oxygenase (PaO) and red chlorophyll catabolite reductase (RCCR). Recently, a gene that modulates disassembly of chlorophyll-protein complexes and activation of pigment ring-opening has been isolated by comparative mapping in monocot species, positional cloning exploiting rice genomics resources and functional testing in Arabidopsis. The corresponding gene in pea has been identified as Mendel's I locus (green/yellow cotyledons). Mutations in this and other chlorophyll catabolic genes have significant consequences, both for the course of leaf senescence and senescence-like stress responses, notably hypersensitivity to pathogen challenge. Loss of chlorophyll can occur via routes other than the PaO/RCCR pathway, resulting in changes that superficially resemble senescence. Such 'pseudosenescence' responses tend to be pathological rather than physiological and may differ from senescence in fundamental aspects of biochemistry and regulation. PMID:18721307

  8. Color measurements as a reliable method for estimating chlorophyll degradation to phaeopigments.

    Science.gov (United States)

    Sanmartín, P; Villa, F; Silva, B; Cappitelli, F; Prieto, B

    2011-07-01

    The application of biocides is a traditional method of controlling biodecay of outdoor cultural heritage. Chlorophyll degradation to phaeopigments is used to test the biocidal efficacy of the antimicrobial agents. In the present study, the usefulness of color measurements in estimating chlorophyll degradation was investigated. An aeroterrestrial stone biofilm-forming cyanobacterium of the genus Nostoc was chosen as test organism, comparing its different behaviour in both planktonic and biofilm mode of growth against the isothiazoline biocide Biotin T®. Changes in A(435 nm)/A(415 nm) and A(665 nm)/A(665a nm) and in the chlorophyll a and adenosine triphosphate (ATP) cell content were compared with the variations in the CIELAB color parameters (L*, a*, b*, C*(ab) and h(ab)). Our findings showed that both the phaeophytination indexes are useful in describing degradation of chlorophyl a to phaeopigments. Moreover, the CIELAB color parameters represented an effective tool in describing chlorophyll degradation. L* CIELAB parameter appeared to be the most informative parameter in describing the biocidal activity of Biotin T® against Nostoc sp. in both planktonic and biofilm mode of growth. PMID:20714920

  9. Chlorophyll formation and the development of photosynthesis in illuminated etiolated pea leaves.

    Science.gov (United States)

    Dowdell, R J; Dodge, A D

    1971-03-01

    The protein synthesis inhibitors chloramphenicol and terramycin, and light of low intensity were used to retard the rate of chlorophyll formation in illuminated dark grown pea leaves. In the control leaves the onset of photosynthesis, as measured by carbon dioxide exchange of the whole leaves, and reduction of ferricyanide and metmyoglobin and photo-oxidation of ascorbate in isolated chloroplasts, was observed after 2-4 hours illumination. The photosynthetic activity of the treated leaves did not commence until 10-12 hours illumination had elapsed. In both the control and treated leaves the onset of photosynthesis occurred when the total chlorophyll content was 0.04 mg/g fresh weight. The precise point of photosynthetic inception was apparently more related to the attainment of a specific total chlorophyl content than to the ratio of chlorophyll a to chlorophyll b. A marked increase in the evolution of carbon dioxide in the light was observed in the treated leaves during the first 10 hours of greening. This observation could not be ascribed to photorespiration since the leaves did not possess an active photosystem. It is suggested that the enhanced respiration may have been due to the light-induced activation of synthetic pathways responsible for the formation of chloroplast constituents. PMID:24493304

  10. Why is the Ratio of Reflectivity Effective for Chlorophyll Estimation in the Lake Water?

    Directory of Open Access Journals (Sweden)

    Kazuo Oki

    2010-07-01

    Full Text Available The reasons why it is effective to estimate the chlorophyll-a concentration with the ratio of spectral radiance reflectance at the red light region and near infrared regions were shown in theory using a two-flow model. It was found that all of the backscattering coefficients can consequently be ignored by using the ratio of spectral radiance reflectance, which is the ratio of the upward radiance to the downward irradiance, at the red light and near infrared regions. In other words, the ratio can be expressed by using only absorption coefficients, which are more stable for measurement than backscattering coefficients. In addition, the band selection is crucial for producing the band ratio when the chlorophyll-a concentration is estimated without the effects of backscattering. I conclude that the two wavelengths selected must be close, but one must be within the absorption range of chlorophyll-a, and the other must be outside of the absorption range of chlorophyll-a, in order to accurately estimate the chlorophyll-a concentration.

  11. The Distribution and Variability of Simulated Chlorophyll Concentration over the Tropical Indian Ocean from Five CMIP5 Models

    Institute of Scientific and Technical Information of China (English)

    LIU Lin; FENG Lin; YU Weidong; WANG Huiwu; LIU Yanliang; SUN Shuangwen

    2013-01-01

    Performances of 5 models from the Coupled Model Intercomparison Project Phase 5 (CMIP5) in simulating the chlorophyll concentration over the tropical Indian Ocean are evaluated.Results show that these models are able to capture the dominant spatial distribution of observed chlorophyll concentration and reproduce the maximum chlorophyll concentration over the western part of the Arabian Sea,around the tip of the Indian subcontinent,and in the southeast tropical Indian Ocean.The seasonal evolution of chlorophyll concentration over these regions is also reproduced with significant amplitude diversity among models.All of 5 models is able to simulate the interannual variability of chlorophyll concentration.The maximum interannual variation occurs at the same regions where the maximum climatological chlorophyll concentration is located.Further analysis also reveals that the Indian Ocean Dipole events have great impact on chlorophyll concentration in the tropical Indian Ocean.In the general successful simulation of chlorophyll concentration,most of the CMIP5 models present higher than normal chlorophyll concentration in the eastern equatorial Indian Ocean.

  12. Effect of Phosphatidylcholine on the Steady State Fluorescence of Chlorophyll in Photosystem Ⅱ Particles

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    Phosphatidylcholine (PC) accounts for less than 1% of the total lipids in plant photosystem II (PSII) particles.In this experiment, PSII particles were reconstituted with PC to construct PSII-PC vesicles.The effect of PC on the steady state fluorescence of chlorophyll (Chl) in PSII particles was studied.The results show that PC significantly affected the fluorescence intensity, but did not obviously affect the fluorescence emission band peak position.PC also did not obviously affect the absorbance at 436 nm or the amide I band peak position in FT-IR spectroscopy of PSII particles.The results suggest that PC may affect the light energy transfer from the antenna chlorophyll molecules to the reaction center chlorophyll molecule (P680).

  13. The evaluation of fish farming impact by nutrient content and chlorophyll A in Mala Lamljana bay

    Directory of Open Access Journals (Sweden)

    Jelic-Mrcelic Gorana

    2013-01-01

    Full Text Available This paper offers a brief review of the impacts of fish farming on the nutrient content and chlorophyll a in Mala Lamljana Bay, Croatia. Local loading of nitrogen and phosphorous compounds in fish farms can be very significant and can represent the largest source of N and P in a given area. Low N and P concentrations, low chlorophyll a concentration and a great variety of phytoplankton species were found in the bay, despite the high nutrient loading during the long history of farming in the bay. The phytoplankton community consisted mostly of diatoms and partly of dinoflagellates. Skeletonema costatum and Chaetoceros compressus were the dominant species (90% in summer chlorophyll, which is typical for Middle Adriatic oligotrophic coastal waters. Nevertheless, further studies are required to determine changes in water column factors and planktonic communities in this area.

  14. Chlorophyll fluorescence, Orbital and Photosynthesis: practical activities integrating concepts of Chemistry, Physics and Biology

    Directory of Open Access Journals (Sweden)

    Elgion Lucio da Silva Loreto

    2013-11-01

    Full Text Available These laboratory activities explore the relationship between the reserve of energy that occur during photosynthesis and the chlorophyll fluorescence emission when in solution as opposed to absence of fluorescence when the chlorophyll are in intact chloroplasts. This proposal can be used as short demo or as  activities with longer duration, to show chlorophyll's properties associated with the photosynthesis. The materials proposed for the implementation of the activities are simple, and possible to building it by the students, enabling the development of various skills and experimental proposals. The protocols are based on observations and record key questions to continue the execution. During the activities, questions promotes pauses for moments of reflection and review of concepts. At the end are presented and discussed proposals for development of interdisciplinary projects.

  15. Structural Effects of Heat-Treated Silica Xerogel Induced by Incorporation of Chlorophyll Species

    Directory of Open Access Journals (Sweden)

    J. R. Martínez

    2007-10-01

    Full Text Available Composites containing chlorophyll aggregates dispersed in amorphous silica are of interest because of their optical attractive properties. The silica powders added with chlorophyll species, prepared by the sol-gel method, were studied using X-ray diffraction, IR spectroscopy and differential temperature analysis. Silica xerogel samples were prepared using an ethanol/H2O/TEOS molar ratio of 4:11.6:1 and loaded with extracts from frozen spinach leaves. The silica xerogel microstructure of the powders was studied as a function of the annealing temperature. We found in our samples partial crystallization of the glass matrix in form of tridymite and cristobalite phases and quenching centers or nonfluorescing aggregates due to denaturation of photosystem promoted by chlorophyll decomposition after 400∘C.

  16. Effects of Molybdenum on the Intermediates of Chlorophyll Biosynthesis in Winter Wheat Cultivars Under Low Temperature

    Institute of Scientific and Technical Information of China (English)

    YU Min; HU Cheng-xiao; WANG Yun-hua

    2006-01-01

    The objective was to probe the site where the biosynthesis of chlorophyll was blocked under Mo deficiency at low temperature, which led to the decrease of chlorophyll in winter wheat cultivars. The intermediates of chlorophyll biosynthesis were analyzed in winter wheat cultivars in soil culture, miniblock culture, and solution culture to study the effects of Mo on chlorophyll biosynthesis without Mo addition (CK, soil available Mo 0.112 mg kg-1) and Mo addition (+ Mo,0.13 mg kg-1 Mo was added). Laevulinic acid (LA), the competitive analog of δ-aminolaevulinic acid (ALA) was also introduced in the experiment. The ratio of Chl a/Chl b was constant between CK and + Mo treatment, whereas it increased at low temperature, which indicated that Mo deficiency did not inhibit the transformation of Chl a to Chl b at low temperature. Under Mo deficiency, the contents of protochlorophyll (Pchl), Mg-protoporphyrin Ⅸ (Mg-Proto Ⅸ),protoporphyrin Ⅸ (proto Ⅸ), and uroporphyrinogen Ⅲ (Uro Ⅲ) decreased [Uro Ⅲ decreased significantly (P < 0.01)],whereas ALA and glutamate increased significantly (P < 0.01) compared with that of Mo addition, which suggested that the transformation from ALA to Ufo Ⅲ might be inhibited. The content of ALA reversed after addition of LA, it was significantly higher (P<0.01) in Mo addition than in CK. The results indicated that the transformation from ALA to Uro Ⅲ was blocked under Mo deficiency, which resulted in the inhibition of the biosynthesis of chlorophyll and led to the decrease of chlorophyll in winter wheat cultivars.

  17. Statistical characteristics of chlorophyll-a concentration in Hong Kong′s coastal waters

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    In this paper seven of the ten Water Control Zones (WCZs) in Hong Kong′s coastal waters with monthly or bi-weekly sampling data of 17 parameters collected at 37 monitoring stations from 1988 to 1999 were selected to analyze the spatial and temporal variations of chlorophyll-a and its influencing factors. Cluster analysis was employed to group the monitoring stations based on the structure of the data set. Multiple step regression was employed to determine the significant influencing factors of chlorophyll-a level. The results suggest that all the monitoring stations could be grouped into two clusters. Cluster I with frequent red tide incidents comprises two WCZs which aresemi-enclosed bays. Cluster II with less red tide occurrence comprises the other five WCZs in an estuarine environment in the west. For both clusters, the organic contents indicator, BOD5, was a common significant influencing factor of the chlorophyll-a level. Nitrogen and light penetration condition related to turbidity, total volatile solids and suspended solids had more influence on the cholophyll-a level in Cluster I than in Cluster II, while phosphorus and oceanographic conditions associated with salinity, temperature, dissolved oxygen and pH were more important in Cluster II than in Cluster 1. Generally, there was a higher average chlorophyll-a level in winter and autumn in a year.The chlorophyll-a level was much higher in Cluster I than in Cluster II among all seasons. Although the chlorophyll-a concentration had great variations from place to place in Hong Kong′s coastal waters, it seemed to have a common long term fluctuation period of 8-10 years with a high-low-high variation in the period in the whole region, which might be influenced by other factors of global scale.

  18. Plant Leaf Chlorophyll Content Retrieval Based on a Field Imaging Spectroscopy System

    Directory of Open Access Journals (Sweden)

    Bo Liu

    2014-10-01

    Full Text Available A field imaging spectrometer system (FISS; 380–870 nm and 344 bands was designed for agriculture applications. In this study, FISS was used to gather spectral information from soybean leaves. The chlorophyll content was retrieved using a multiple linear regression (MLR, partial least squares (PLS regression and support vector machine (SVM regression. Our objective was to verify the performance of FISS in a quantitative spectral analysis through the estimation of chlorophyll content and to determine a proper quantitative spectral analysis method for processing FISS data. The results revealed that the derivative reflectance was a more sensitive indicator of chlorophyll content and could extract content information more efficiently than the spectral reflectance, which is more significant for FISS data compared to ASD (analytical spectral devices data, reducing the corresponding RMSE (root mean squared error by 3.3%–35.6%. Compared with the spectral features, the regression methods had smaller effects on the retrieval accuracy. A multivariate linear model could be the ideal model to retrieve chlorophyll information with a small number of significant wavelengths used. The smallest RMSE of the chlorophyll content retrieved using FISS data was 0.201 mg/g, a relative reduction of more than 30% compared with the RMSE based on a non-imaging ASD spectrometer, which represents a high estimation accuracy compared with the mean chlorophyll content of the sampled leaves (4.05 mg/g. Our study indicates that FISS could obtain both spectral and spatial detailed information of high quality. Its image-spectrum-in-one merit promotes the good performance of FISS in quantitative spectral analyses, and it can potentially be widely used in the agricultural sector.

  19. Determination of chlorophyll a and total phosphorus abundance in organic manured fish ponds

    Directory of Open Access Journals (Sweden)

    Kelvin M. Chanda

    2012-09-01

    Full Text Available An experiment was conducted for 6 weeks (between August and September 2010 with 4treatments (T1: poultry manure, T2: cattle manure, T3: poultry and cattle manure and T4: control-nomanure assigned to 8 concrete ponds at random to determine chlorophyll a and total phosphorusabundance in organic manured fish ponds. Results of the study suggest that T1, T2, and T3 had an effecton chlorophyll a and total phosphorus abundance in organic manured ponds. The final mean average forchlorophyll a ranged from 0.0105mg/m3 to 0.045mg/m3 and that of total phosphorus ranged from0.024mg/50mL to 0.522mg/50mL. Chlorophyll a and phosphorus were positively correlated with acoefficient of 0.92 and it was significant (p ≤ 0.05. However, weekly performance of chlorophyll a andtotal phosphorus was higher in T3 compared to other treatments. The treatments also showeddifferences in the number of plankton species available. Phytoplankton species in T3 increased from 888in week three to 933 in week six. However, the zooplankton species reduced from 10 in week three to 4in week six compared to other treatments. These results indicate that animal manure varied ininfluencing the production of chlorophyll a, planktons and phosphorus. The variation may be attributed tofeed nutritive value of the animals to which they were fed. Farmers should therefore be encouraged touse a combination of poultry and cattle manure to obtain maximum benefits in increasing chlorophyll aand total phosphorus.

  20. Plant leaf chlorophyll content retrieval based on a field imaging spectroscopy system.

    Science.gov (United States)

    Liu, Bo; Yue, Yue-Min; Li, Ru; Shen, Wen-Jing; Wang, Ke-Lin

    2014-01-01

    A field imaging spectrometer system (FISS; 380-870 nm and 344 bands) was designed for agriculture applications. In this study, FISS was used to gather spectral information from soybean leaves. The chlorophyll content was retrieved using a multiple linear regression (MLR), partial least squares (PLS) regression and support vector machine (SVM) regression. Our objective was to verify the performance of FISS in a quantitative spectral analysis through the estimation of chlorophyll content and to determine a proper quantitative spectral analysis method for processing FISS data. The results revealed that the derivative reflectance was a more sensitive indicator of chlorophyll content and could extract content information more efficiently than the spectral reflectance, which is more significant for FISS data compared to ASD (analytical spectral devices) data, reducing the corresponding RMSE (root mean squared error) by 3.3%-35.6%. Compared with the spectral features, the regression methods had smaller effects on the retrieval accuracy. A multivariate linear model could be the ideal model to retrieve chlorophyll information with a small number of significant wavelengths used. The smallest RMSE of the chlorophyll content retrieved using FISS data was 0.201 mg/g, a relative reduction of more than 30% compared with the RMSE based on a non-imaging ASD spectrometer, which represents a high estimation accuracy compared with the mean chlorophyll content of the sampled leaves (4.05 mg/g). Our study indicates that FISS could obtain both spectral and spatial detailed information of high quality. Its image-spectrum-in-one merit promotes the good performance of FISS in quantitative spectral analyses, and it can potentially be widely used in the agricultural sector. PMID:25341439

  1. Experiments in optimizing simulations of the subsurface chlorophyll maximum in the South China Sea

    Science.gov (United States)

    Wang, Siying; Li, Shiyu; Hu, Jiatang; Geng, Bingxu

    2016-04-01

    The subsurface chlorophyll maximum (SCM) is widespread in the oligotrophic ocean and significantly contributes to primary production. One reason for the SCM formation is believed to be the rapid export of phytoplankton from surface layers, which might be caused by aggregation, faster sinking rates under nutrient limitation, or the formation of a resting stage. In this study, these three processes were included in a biological model to investigate their contributions to subsurface chlorophyll. To further identify their individual effects on SCM formation, four modeling experiments were carried out. Three used a simple approach with either (a) density-dependent aggregation, (b) accelerated sinking rate of phytoplankton, or (c) a resting stage. The other experiment combined all three approaches (a-c). A set of observations in the South China Sea was used to optimize the four experiments and compare their abilities to replicate observed values. The results of the experiments with the resting stage showed the best fit to the field observations. All experiments were able to capture major features of the chlorophyll field (e.g. surface bloom and SCM). The experiment with accelerated sinking rate failed to reproduce the observed profile of particulate organic carbon. The experiment with only aggregation predicted lower chlorophyll concentrations in summer than those measured in the field, while experiments with the resting stage reproduced more accurate chlorophyll concentrations. Formulas including the resting stage more successfully captured the timing of phytoplankton export than did those including aggregation and accelerated sinking rate. The processes of aggregation and accelerated sinking rate made small contributions to the SCM formation in the last experiment. Overall, these results show that introducing the resting stage improves SCM simulations of the South China Sea. The results of the experiment with only the resting stage showed that the resting cells shift

  2. Determination of double decker sanwich structured La—substituted chlorophyll a by EXAFS

    Institute of Scientific and Technical Information of China (English)

    W.Chen; Z.Wei; F.Hong; Y.Tao; G.Zhao; J.Yang; S.lkeda; J.Jiang; T.Hu

    2001-01-01

    As a representative naural porphyrin derivative,it is interesting to know the chemical form of lanthanide in chlorophyll a.We select the natural fern dicranopteris dichotoma,the most lanthanide-concentrated plant known,to isolate the chlorophyll a for our study. It is found by EXAFS that lanthanum substutes in the magnesium position in chorophyll and coordinates with the porphyrin ring.The lanthanum is seen to have a similar coordination structure to a sandwich-type lanthanide complex,with the La surrounded by eight nitrogen atoms from two porphyrin rings with average La-N bond length of 2.65A.

  3. Gamma ray induced seedling injury and chlorophyll mutants in two varieties of rice

    International Nuclear Information System (INIS)

    Dry, well filled seeds of rice cultivars Basmati and Phalguna were irradiated with 20, 30, 40, and 50 kR gamma ray doses with a view to study their radio sensitivity in inducing seedling injury and chlorophyll mutants. In general, the percentage of germination, survival, seedling height and leaf number decreased in the irradiated population. The spectrum of chlorophyll mutants induced include albino, viridis, xantha and other categories like striata, zebra and maculata. Viridis was more predominant in Basmati whereas xantha was more in phalguna. (author). 7 refs., 2 tabs

  4. Determination of chlorophyll a and total phosphorus abundance in organic manured fish ponds

    OpenAIRE

    Kelvin M. Chanda; Confred G. Musuka

    2012-01-01

    An experiment was conducted for 6 weeks (between August and September 2010) with 4treatments (T1: poultry manure, T2: cattle manure, T3: poultry and cattle manure and T4: control-nomanure) assigned to 8 concrete ponds at random to determine chlorophyll a and total phosphorusabundance in organic manured fish ponds. Results of the study suggest that T1, T2, and T3 had an effecton chlorophyll a and total phosphorus abundance in organic manured ponds. The final mean average forchlorophyll a range...

  5. Chlorophyll Fluorescence Spectra as an Indicator of X-Ray + EMS-Induced Phytotoxicity in Safflower

    OpenAIRE

    Pandey, Jitendra Kumar; Srivastava, Preeti; Yadav, Ram Singh; Gopal, Ram

    2012-01-01

    The present investigation deals with the study of in vivo laser-induced chlorophyll florescence spectra (LICF) of safflower leaves (Carthamus tinctorius L.) for X-rays + EMS-treated plants. Seeds were treated with different doses of X-ray + EMS (5, 8, 12, 25, and 30 Kr + 0.5% EMS) and were grown in the green house. The effects of the concerned treatment on chlorophyll (Chl) contents and Chl fluorescence were investigated after 7 days of germination. Results obtained revealed that the values o...

  6. A new indicator in early drought diagnosis of cucumber with chlorophyll fluorescence imaging

    Science.gov (United States)

    Wang, Heng; Li, Haifeng; Xu, Liang; Liu, Xu

    2015-05-01

    Crop population growth information can more fully reflect the state of crop growth, eliminate individual differences, and reduce error in judgment. We have built a suitable plant population growth information online monitoring system with the plant chlorophyll fluorescence and spectral scanning imaging to get the crop growth status. On the basis of the fluorescence image detection, we have studied the early drought diagnosis of cucumber. The typical chlorophyll fluorescence parameters can not reflect the drought degree significantly. We define a new indication parameter (DI). With the drought deepening, DI declines. DI can enlarge the early manifestation of cucumber drought (3-5 days), indicate more significantly in the early drought diagnosis of cucumber.

  7. Spectral and physiological information from chlorophyll fluorescence signals in the detection of pine damage

    Energy Technology Data Exchange (ETDEWEB)

    Meinander, O. [Finnish Meteorological Inst., Helsinki (Finland). Air Quality Dept.; Somersalo, S. [Helsinki Univ., Helsinki (Finland). Dept. of Plant Biology

    1995-12-31

    Photosynthesis is often among the first targets of the air pollution stress of plants. As chlorophyll fluorescence is a process competing with photosynthetic electron transport it can be employed to study the potential photosynthetic capacity and to detect damage to the photosynthetic apparatus. Many previous studies have shown that chlorophyll fluorescence can be a powerful tool in the detection of forest damage. In this preliminary study, singular value analysis of the fluorescence induction curves was used together with the traditional way of analyzing fluorescence measurements. The experimental data were collected from ozone and carbon dioxide fumigated Scots pine saplings. (author)

  8. Mixed layer variability and chlorophyll a biomass in the Bay of Bengal

    OpenAIRE

    J. Narvekar; Prasanna Kumar, S.

    2013-01-01

    Mixed layer is the most variable and dynamically active part of the marine environment that couples the underlying ocean to the atmosphere and plays an important role in determining the chlorophyll concentration. In this paper we examined the seasonal variability of the mixed layer depth in the Bay of Bengal, the factors responsible for it and the coupling of mixed layer processes to the chlorophyll biomass using a suite of in situ as well as remote sensing data. The basin-wide mixed layer de...

  9. The chlorophyll-binding protein CP47 in photosystem II. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Vermaas, W.F.J.

    1995-12-31

    Generally, light-harvesting chlorophyll-binding proteins (LHCP) of the Cab family that are prevalent antenna systems in plants are thought to be absent in cyanobacteria. Therefore, it often is tacitly assumed that in cyanobacteria all chlorophyll is associated with the PS II and PS I core antenna. For this reason, it was of interest to investigate what the effect would be of genetic deletion of both the PS I core complex and the PS II core antenna in Synechocystis. Therefore, a mutant was made in which the psaAB genes for the PS I core were deleted, in addition to deletion or inactivation of psbB and/or psbC (coding for CP43). In this series of mutants, also apcE was deleted. In the absence of both CP47 and CP43, also the PS II reaction center proteins D1 and D2 were not detectable in the thylakoid membrane. Thus, both PS II and PS I were deleted in the resulting strains. Nonetheless, a significant amount of chlorophyll (about 15% of that present when PS II was left intact) was found to remain in the PS I-less, psbB{sup {minus}}, psbC{sup {minus}}, apcE{sup {minus}} mutant. This chlorophyll had fluorescence characteristics resembling those of LHC II in higher plants, with a 678 nm emission maximum at 77 K. The properties of this chlorophyll remaining in the absence of PS II and PS I in Synechocystis did not resemble those of chlorophyll bound to a CP43-like protein that has been found in cyanobacteria and that is expressed under iron-stress conditions. However, some similarities in terms of fluorescence emission were observed with the isolated 22 kDa protein encoded by psbS. The role and association of the remaining chlorophyll in the PS I-less, psbB{sup {minus}}, psbC{sup {minus}}, apcE{sup {minus}} mutant remains unclear, however, this chlorophyll protein is expected to be functionally connected to PS II when this photosystem is present.

  10. Chlorophyll a Covalently Bonded to Organo-Modified Translucent Silica Xerogels: Optimizing Fluorescence and Maximum Loading

    Directory of Open Access Journals (Sweden)

    M. A. García-Sánchez

    2016-07-01

    Full Text Available Chlorophyll is a pyrrolic pigment with important optical properties, which is the reason it has been studied for many years. Recently, interest has been rising with respect to this molecule because of its outstanding physicochemical properties, particularly applicable to the design and development of luminescent materials, hybrid sensor systems, and photodynamic therapy devices for the treatment of cancer cells and bacteria. More recently, our research group has been finding evidence for the possibility of preserving these important properties of substrates containing chlorophyll covalently incorporated within solid pore matrices, such as SiO2, TiO2 or ZrO2 synthesized through the sol-gel process. In this work, we study the optical properties of silica xerogels organo-modified on their surface with allyl and phenyl groups and containing different concentrations of chlorophyll bonded to the pore walls, in order to optimize the fluorescence that these macrocyclic species displays in solution. The intention of this investigation was to determine the maximum chlorophyll a concentration at which this molecule can be trapped inside the pores of a given xerogel and to ascertain if this pigment remains trapped as a monomer, a dimer, or aggregate. Allyl and phenyl groups were deposited on the surface of xerogels in view of their important effects on the stability of the molecule, as well as over the fluorescence emission of chlorophyll; however, these organic groups allow the trapping of either chlorophyll a monomers or dimers. The determination of the above parameters allows finding the most adequate systems for subsequent in vitro or in vivo studies. The characterization of the obtained xerogels was performed through spectroscopic absorption, emission and excitation spectra. These hybrid systems can be employed as mimics of natural systems; the entrapment of chlorophyll inside pore matrices indicates that it is possible to exploit some of the most

  11. Spectral luminescence and photochemical properties of chlorophyll a in solution containing carbon tetrachloride

    International Nuclear Information System (INIS)

    Studies were conducted on photophysical and photochemical processes in chlorophyll a in carbon tetrachloride and ether by means of flash photolysis, electron spin resonance, and fluorescence spectroscopy. Lifetimes and quenching of triplet states were analyzed and absorption spectra and fluorescence decay times are given. The kinetics of triplet-triplet absorption and hyperfine structure were determined. An absolute quantum yield of the photochemical reaction was measured within the range of linear dependence of the optical density on the time of chlorophyll a irradiation by a krypton laser and the excitation wavelength of 647.1 nm

  12. Chlorophyll a Covalently Bonded to Organo-Modified Translucent Silica Xerogels: Optimizing Fluorescence and Maximum Loading.

    Science.gov (United States)

    García-Sánchez, M A; Serratos, I N; Sosa, R; Tapia-Esquivel, T; González-García, F; Rojas-González, F; Tello-Solís, S R; Palacios-Enriquez, A Y; Esparza Schulz, J M; Arrieta, A

    2016-01-01

    Chlorophyll is a pyrrolic pigment with important optical properties, which is the reason it has been studied for many years. Recently, interest has been rising with respect to this molecule because of its outstanding physicochemical properties, particularly applicable to the design and development of luminescent materials, hybrid sensor systems, and photodynamic therapy devices for the treatment of cancer cells and bacteria. More recently, our research group has been finding evidence for the possibility of preserving these important properties of substrates containing chlorophyll covalently incorporated within solid pore matrices, such as SiO₂, TiO₂ or ZrO₂ synthesized through the sol-gel process. In this work, we study the optical properties of silica xerogels organo-modified on their surface with allyl and phenyl groups and containing different concentrations of chlorophyll bonded to the pore walls, in order to optimize the fluorescence that these macrocyclic species displays in solution. The intention of this investigation was to determine the maximum chlorophyll a concentration at which this molecule can be trapped inside the pores of a given xerogel and to ascertain if this pigment remains trapped as a monomer, a dimer, or aggregate. Allyl and phenyl groups were deposited on the surface of xerogels in view of their important effects on the stability of the molecule, as well as over the fluorescence emission of chlorophyll; however, these organic groups allow the trapping of either chlorophyll a monomers or dimers. The determination of the above parameters allows finding the most adequate systems for subsequent in vitro or in vivo studies. The characterization of the obtained xerogels was performed through spectroscopic absorption, emission and excitation spectra. These hybrid systems can be employed as mimics of natural systems; the entrapment of chlorophyll inside pore matrices indicates that it is possible to exploit some of the most physicochemical

  13. Heat Denaturation of Protein Structures and Chlorophyll States in PSII Membranes

    Institute of Scientific and Technical Information of China (English)

    李冬海; 阮翔; 许强; 王可玢; 公衍道; 匡廷云; 赵南明

    2002-01-01

    Heat denaturation is an important technique in the study of the structure and function of photosynthetic proteins. Heat denaturation of photosystem II (PSII) membrane was studied using circular dichroism (CD) spectroscopy, differential scanning calorimetry (DSC) and oxygen electrode. Complete loss of oxygen-evolving activity of the PSII membrane was observed at temperatures below 45℃. The decrease of excitonic interaction between chlorophyll molecules occurred more rapidly than the change of the protein secondary structure of the PSII membrane at temperatures above 45℃. The results indicate that the protein secondary structure of the membrane proteins in PSII membranes is more stable than the excitonic interaction between chlorophyll molecules during heat denaturation.

  14. Development of the spectrometric imaging apparatus of laser induced fluorescence from plants and estimation of chlorophyll contents of rice leaves; Laser reiki keiko sokutei sochi no kaihatsu to inehanai no chlorophyll ganryo no suitei

    Energy Technology Data Exchange (ETDEWEB)

    Nakaya, K.; Shoji, K.; Hanyu, H.

    1999-05-01

    Photosynthetic activity of plants is an important factor to assess the micrometeorological effect of plant canopy or to estimate the influence of circumstances such as water stress. Light illumination induces fluorescence from a leaf or suspension of chloroplasts. The red chlorophyll fluorescence had been used to determine the process of the electron transportation in photosynthetic reaction. The fluorescence source other than chlorophyll is not announced sufficiently, but is supposed to be useful to determine the contents of the substance corresponding to physiological response of plants. We developed a fluorescence imaging apparatus to observe spectrum and distribution of laser induced fluorescence from a leaf. Pulsed UV-laser (Nd:YAG) induced blue-green fluorescence and red chlorophyll fluorescence from a green leaf. The pulse modulated measuring light and CCD with image-intensifier (ICCD) enable to detect the fluorescence from plants under illumination. The laser induced fluorescence (LIF) spectra were investigated to estimate the chlorophyll contents in leaves of rice. During the greening course of dark grown etiolated rice leaves, chlorophyll contents were determined using the extraction of leaves and steady state LIF spectra were measured. As a result, the ratio of fluorescent intensity between blue-green and red peaks (F460/F740 and F510/F740) decreased in proportion to alteration of chlorophyll contents respectively. These fluorescence intensity ratios perform more precise estimation of higher chlorophyll contents of leaves than reported red chlorophyll fluorescence intensity ratio (F690/E740). (author)

  15. Effect of changes in chlorophyll concentration on photosynthetic properties I. Fluorescence and absorption of greening bean leaves

    NARCIS (Netherlands)

    Goedheer, J.C.

    1961-01-01

    In order to obtain new information about the way of functioning of chlorophyll in vivo a study was made of optical properties and photosynthesis under condition of a low chlorophyll content in the leave. It was found that the fluorescence yeild of greening bean leaves decreased from a value approxim

  16. Novel type of red-shifted chlorophyll a antenna complex from Chromera velia: II. Biochemistry and spectroscopy

    Czech Academy of Sciences Publication Activity Database

    Bína, David; Gardian, Zdenko; Herbstová, Miroslava; Kotabová, Eva; Koník, P.; Litvín, Radek; Prášil, Ondřej; Tichý, Josef; Vácha, František

    2014-01-01

    Roč. 1837, č. 6 (2014), s. 802-810. ISSN 0005-2728 R&D Projects: GA ČR GBP501/12/G055 Institutional support: RVO:60077344 ; RVO:61388971 Keywords : Chromera velia * red-shifted chlorophyll * Chlorophyll fluorescence Subject RIV: CE - Biochemistry; CE - Biochemistry (MBU-M) Impact factor: 5.353, year: 2014

  17. Optimization and effects of different culture conditions on growth of Halomicronema hongdechloris – a filamentous cyanobacterium containing chlorophyll f

    OpenAIRE

    Li, Yaqiong; Lin, Yuankui; Patrick C. Loughlin; Chen, Min

    2014-01-01

    A chlorophyll f containing cyanobacterium, Halomicronema hongdechloris (H. hongdechloris) was isolated from a stromatolite cyanobacterial community. The extremely slow growth rate of H. hongdechloris has hindered research on this newly isolated cyanobacterium and the investigation of chlorophyll f-photosynthesis. Therefore, optimizing H. hongdechloris culture conditions has become an essential requirement for future research. This work investigated the effects of various culture conditions, e...

  18. Estimation of digestive stability and bioavailability of chlorophylls by an in vitro digestion/Caco-2 cell culture model

    OpenAIRE

    Gallardo Guerrero, Lourdes; Gandul-Rojas, Beatriz; Mínguez Mosquera, María Isabel

    2006-01-01

    The aim of this work was to study the effect of food matrix both on the chlorophyll pigment transformations and on their micellarization as a measure of bioavailability, using an two-stage in vitro digestion model. We also validate the above mentioned bioavailability measurement by evaluating the absorption of the micellarized chlorophyll pigments by Caco-2 human intestinal cell cultures.

  19. A GIS Approach to Wind,SST(Sea Surface Temperature) and CHL(Chlorophyll) variations in the Caspian Sea

    Science.gov (United States)

    Mirkhalili, Seyedhamzeh

    2016-07-01

    Chlorophyll is an extremely important bio-molecule, critical in photosynthesis, which allows plants to absorb energy from light. At the base of the ocean food web are single-celled algae and other plant-like organisms known as Phytoplankton. Like plants on land, Phytoplankton use chlorophyll and other light-harvesting pigments to carry out photosynthesis. Where Phytoplankton grow depends on available sunlight, temperature, and nutrient levels. In this research a GIS Approach using ARCGIS software and QuikSCAT satellite data was applied to visualize WIND,SST(Sea Surface Temperature) and CHL(Chlorophyll) variations in the Caspian Sea.Results indicate that increase in chlorophyll concentration in coastal areas is primarily driven by terrestrial nutrients and does not imply that warmer SST will lead to an increase in chlorophyll concentration and consequently Phytoplankton abundance.

  20. Identical substitutions in magnesium chelatase paralogs result in chlorophyll deficient soybean mutants

    Science.gov (United States)

    The soybean (Glycine max (L.) Merr.) chlorophyll deficient line MinnGold is a spontaneous mutant characterized by yellow foliage. Map-based cloning and transgenic complementation revealed that the mutant phenotype is caused by a non-synonymous nucleotide substitution in the third exon of a Mg-chelat...

  1. Cross-system comparison of factors influencing chlorophyll-a concentration in Oregon estuaries

    Science.gov (United States)

    Water column chlorophyll-a (chla) is a proxy for phytoplankton biomass and is often used as a biological response indicator of eutrophication. Although watershed nutrient loading may influence chla concentration in estuaries, factors such as freshwater inflow, residence time, and...

  2. Effect of different temperature regimes on the chlorophyll a concentration in four species of Antarctic macroalgae

    Digital Repository Service at National Institute of Oceanography (India)

    Dhargalkar, V.K.

    from beneath the sea-ice from the coast of the Vestfold Hills, Antarctica were cultured under different temperature regimes (- 4, -1.8, +4, +12, +20°C). The algae were cultured at each of these temperatures and Chlorophyll a concentrations of the algae...

  3. PREDICTING CONCENTRATION OF TOTAL PHOSPHORUS AND CHLOROPHYLL 'A' IN A LAKE WITH SHORT HYDRAULIC RESIDENCE TIME

    Science.gov (United States)

    The relationship between total phosphorus and chlorophyll a concentration was determined for Skinner Lake, Indiana over an annual cycle in 1978-79. Total nitrogen: total phosphorus ratios in the epilimnion ranged from 19 to 220 suggesting a phosphorus-dependent algal yield in the...

  4. Chlorophyll biosynthesis and chloroplast development in etiolated seedlings of Ginkgo biloba L

    Czech Academy of Sciences Publication Activity Database

    Pavlovič, A.; Slováková, L.; Demko, V.; Durchan, Milan; Mikulová, K.; Hudák, J.

    2009-01-01

    Roč. 47, č. 4 (2009), s. 510-516. ISSN 0300-3604 Institutional research plan: CEZ:AV0Z50510513 Keywords : Aminolevulinic acid * Ginkgo biloba * light-independent chlorophyll biosynthesis Subject RIV: CE - Biochemistry Impact factor: 1.072, year: 2009

  5. Feeding with aminolevulinic acid increased chlorophyll content in Norway spruce (Picea abies) in the dark

    Czech Academy of Sciences Publication Activity Database

    Pavlovič, A.; Demko, V.; Durchan, Milan; Hudák, J.

    2009-01-01

    Roč. 47, č. 4 (2009), s. 631-634. ISSN 0300-3604 Institutional research plan: CEZ:AV0Z50510513 Keywords : Aminolevulinic acid * Ginkgo biloba * light-independent chlorophyll biosynthesis Subject RIV: CE - Biochemistry Impact factor: 1.072, year: 2009

  6. Interactions between iron and titanium metabolism in spinach: A chlorophyll fluorescence study in hydropony

    Czech Academy of Sciences Publication Activity Database

    Cígler, Petr; Olejníčková, Julie; Hrubý, Martin; Cséfalvay, Ladislav; Peterka, J.; Kužel, S.

    2010-01-01

    Roč. 167, č. 18 (2010), s. 1592-1597. ISSN 0176-1617 Institutional research plan: CEZ:AV0Z40550506; CEZ:AV0Z40500505; CEZ:AV0Z60870520 Keywords : chlorophyll fluorescence * iron * photosynthetic apparatus * spinach * titanium Subject RIV: CC - Organic Chemistry Impact factor: 2.677, year: 2010

  7. The effects of different salt concentrations on growth and chlorophyll content of some pumpkin rootstocks

    Directory of Open Access Journals (Sweden)

    Köksal AYDİNŞAKİR

    2015-12-01

    Full Text Available This study was conducted to determine the effects of different salinity levels, (0.7, 4.0, 8.0, 12.0, 16.0 dS m-1 on some physiological parameters of Obez F1, Ferro F1, RS841 F1, which are used as rootstocks in watermelon cultivation. Salty irrigation water was obtained through mixing of NaCl and CaCl2 salt into tap water. When the plants were at the 3-4 leaf stage, different salinity levels were applied. Plants were harvested during the phase of florescence. The study was carried out using split plots in randomized complete block design while rootstocks are main plot, salinity levels are sub-plot with three replications. While the salinity level was increasing, the physiological parameters decreased in each three rootstocks. While the plant height changed between 14.4-107.1 cm, the plant leaf area varied between 152.0-2182.7 cm2. Chlorophyll-a, chlorophyll-b and total carotenoid values decreased as the salinity level increased. Excluding the maximum value obtained from control plot, the highest chlorophyll-a, chlorophyll-b, and total carotenoid values were obtained in Obez variety under 4.0 dS m-1 application with 14.8 mg l-1, 12.8 mg l-1 and 0.28 mg g-1 fw, respectively.

  8. Effect of drought stress on yield, proline and chlorophyll contents in three chickpea cultivars

    NARCIS (Netherlands)

    Mafakheri, A.; Siosemardeh, A.; Bahramnejad, B.; Struik, P.C.; Sohrabi, Y.

    2010-01-01

    Drought stress is one of the major abiotic stresses in agriculture worldwide. This study was carried out to investigate the effect of drought stress on proline content, chlorophyll content, photosynthesis and transpiration, stomatal conductance and yield characteristics in three varieties of chickpe

  9. Induction of the 'in vivo' chlorophyll fluorescence excited by CW and pulse-periodical laser radiation

    International Nuclear Information System (INIS)

    Inductional changes of fluorescence of the native chlorophyll molecules in plant leaves excited by CW and pulse-periodical laser radiation are studied. The opportunity of controlling of the photosynthesis efficiency through fluorescence response at different rates of the electron flow in charge transfer chain of the photosynthetic apparatus of plant is shown. (author). 13 refs.; 4 refs

  10. Control of electron transport processes in photosystem II by chlorophyll fluorescence parameters

    International Nuclear Information System (INIS)

    In this work the opportunity of the electron photosynthetic transport control in plant leaves by means of the prompt and delayed chlorophyll fluorescence are shown. Influence of environment conditions (temperature, water provision) is considered in respect to their limiting role in efficiency of the energy-transmutation processes in the photosynthetic apparatus. (author)

  11. Behavior of Sethoxydim Alone or in Combination with Turnip Oils on Chlorophyll Fluorescence Parameter

    Directory of Open Access Journals (Sweden)

    Hossein HAMMAMI

    2014-03-01

    Full Text Available Sethoxydim is an acetyl-coenzyme A carboxylase (ACCase inhibitor that changed the shape of the chlorophyll fluorescence curve (kautsky curve in wild oat (Avena ludoviciana Durieu. in greenhouse experiment. This experiment was conducted as completely randomized factorial design with three replications at the College of Agriculture, Ferdowsi University of Mashhad, Iran, during 2012. Results of this study revealed that sethoxydim only and plus emulsifiable turnip oil changed the shape of the chlorophyll fluorescence curve (kautsky curve 7 days after spraying. Sethoxydim plus emulsifiable turnip oil changed the shape of the kautsky curve more than for sethoxydim only. We found that in our study the fv/fm (maximum quantum efficiency was closely linked to the fresh and dry weight dose-response. Sethoxydim plus emulsifiable turnip oil proved more rapidly effect on fv/fm in comparison with sethoxydim only. The fresh and dry weight dose-response relationship with fv/fm showed a similar behavior. This study revealed a good relation between fresh and dry weight according with values of 28 DAS and fv/fm 7 DAS. In general, the findings of this study revealed that Fv/Fm is a good parameter for evaluating effect of sethoxydim little time after spraying. Also, this research showed that 4 folds more time for classical screening methods comparing to chlorophyll fluorescence method. Thereupon, classical screening methods may be replaced by chlorophyll fluorescence method in future.

  12. Plastid ultrastructure in chlorophyll mutant sectors of leaves in seed-irradiated lactuceae

    International Nuclear Information System (INIS)

    In the M1 plants from seed irradiated Lactuceae, at least two types of chlorophyll mutant, 'albo-xantha a' common to two cultivars of L. sativa, and 'albo-xantha b' common to L. sativa and L. serriola, were recognised (c.f. von Wettstein et al. 1971, von Wettstein 1980). They are illustrated and discussed. (author)

  13. Natural chlorophyll but not chlorophyllin prevents heme-induced cytotoxic and hyperproliferative effects in rat colon

    NARCIS (Netherlands)

    Vogel, de J.; Jonker-Termont, D.S.M.L.; Katan, M.B.; Meer, van der R.

    2005-01-01

    Diets high in red meat and low in green vegetables are associated with an increased risk of colon cancer. In rats, dietary heme, mimicking red meat, increases colonic cytotoxicity and proliferation of the colonocytes, whereas addition of chlorophyll from green vegetables inhibits these heme-induced

  14. Chlorophyll-a, Orbview-2 SeaWiFS, 0.0125 degrees, West US

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA CoastWatch distributes chlorophyll-a concentration images from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) on the Orbview-2 satellite. Because data is...

  15. Influence of a tropical cyclone on chlorophyll-a concentration in the Arabian Sea

    Digital Repository Service at National Institute of Oceanography (India)

    Subrahmanyam, B; Rao, K.H.; Rao, N.S.; Murty, V.S.N.

    The effect of a tropical cyclone on the variation of phytoplankton biomass in terms of surface chlorophyll-a is brought out based on satellite observations and mixed layer model simulations in the Arabian Sea during 21 May-3 June 2001. Along...

  16. Non-invasive method for in vivo detection of chlorophyll precursors

    DEFF Research Database (Denmark)

    Kristiansen, Kim Anker; Khrouchtchova, Anastassia; Stenbæk, Anne;

    2009-01-01

    Traditionally chlorophyll (Chl) and Chl precursors have been studied in vitro or in leaf tissue at low temperature. These methods are destructive and make it impossible to work with the same individual plant later on. In this paper we present a method for in vivo detection of Chl and its precurso...

  17. Mutational analysis of three bchH paralogs in (bacterio-)chlorophyll biosynthesis in Chlorobaculum tepidum

    DEFF Research Database (Denmark)

    Gomez Maqueo Chew, Aline; Frigaard, Niels-Ulrik; Bryant, Donald A

    2009-01-01

    The first committed step in the biosynthesis of (bacterio-)chlorophyll is the insertion of Mg2+ into protoporphyrin IX by Mg-chelatase. In all known (B)Chl-synthesizing organisms, Mg-chelatase is encoded by three genes that are homologous to bchH, bchD, and bchI of Rhodobacter spp. The genomes of...

  18. Effects of sodium pentaborate pentahydrate exposure on Chlorella vulgaris growth, chlorophyll content, and enzyme activities.

    Science.gov (United States)

    Chen, Xueqing; Pei, Yuansheng

    2016-10-01

    Sodium pentaborate pentahydrate (SPP) is a rare mineral. In this study, SPP was synthesized from boric acid and borax through low-temperature crystallization, and its effects on the growth of the alga, Chlorella vulgaris (C. vulgaris) were assessed. The newly synthesized SPP was characterized by chemical analysis, X-ray diffraction, Fourier-transform infrared spectroscopy, Raman spectroscopy, thermogravimetric analysis, and differential thermal analysis. The changes in C. vulgaris growth, chlorophyll content, and enzyme activities upon exposure to SPP for 168h were evaluated. Results showed that SPP treatment was detrimental to C. vulgaris growth during the first 24-120h of exposure. The harmful effects, however, diminished over time (168h), even at an effective medium concentration of 226.37mg BL(-1) (the concentration of boron applied per liter of culture medium). A similar trend was observed for chlorophyll content (chlorophyll a and b) and indicated that the photosynthesis of C. vulgaris was not affected and that high levels of SPP may even promote chlorophyll synthesis. Superoxide dismutase and catalase activities of C. vulgaris increased during 24-120h exposure to SPP, but these activities gradually decreased as culture time progressed. In other words, the initial detrimental effects of synthetic SPP on C. vulgaris were temporary and reversible. This research provides a scientific basis for applications of SPP in the environment. PMID:27367150

  19. Chlorophyll-a, Orbview-2 SeaWiFS, 0.1 degrees, Global

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NASA GSFC Ocean Color Web distributes science-quality chlorophyll-a concentration data from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) on the Orbview-2...

  20. Spectrometric estimation of the content of chlorophyll in plants subjected to anthropogenic action

    Science.gov (United States)

    Quliev, R. B.; Azizov, B. M.; Abbaszadeh, A. A.

    2009-03-01

    Spectral methods for determining the content of chlorophyll in vegetation subjected to anthropogenic action are considered. The regularities in the changes in the spectral radiance coefficients of vegetation in certain intervals of the visible range are considered in relation to the degree of remoteness of the pollution source.

  1. Comparison of chlorophyll in the Red Sea derived from MODIS-Aqua and in vivo fluorescence

    KAUST Repository

    Brewin, Robert J W

    2013-09-01

    The Red Sea is a unique marine environment but relatively unexplored. The only available long-term biological dataset at large spatial and temporal scales is remotely-sensed chlorophyll observations (an index of phytoplankton biomass) derived using satellite measurements of ocean colour. Yet such observations have rarely been compared with in situ data in the Red Sea. In this paper, satellite chlorophyll estimates in the Red Sea from the MODIS instrument onboard the Aqua satellite are compared with three recent cruises of in vivo fluorometric chlorophyll measurements taken in October 2008, March 2010 and September to October 2011. The performance of the standard NASA chlorophyll algorithm, and that of a new band-difference algorithm, is found to be comparable with other oligotrophic regions in the global ocean, supporting the use of satellite ocean colour in the Red Sea. However, given the unique environmental conditions of the study area, regional algorithms are likely to fare better and this is demonstrated through a simple adjustment to the band-difference algorithm. © 2013 Elsevier Inc.

  2. Chlorophyll fluorescence as an indicator of plant water status in cotton

    Science.gov (United States)

    Various methods exist for the measurement of plant water status. Plant breeders value methods that are fast and inexpensive lending themselves to the efficient evaluation of large segregating populations. Chlorophyll fluorescence is a parameter commonly measured by plant physiologists when studying ...

  3. Fast and nondestructive method for leaf level chlorophyll estimation using hyperspectral LiDAR

    NARCIS (Netherlands)

    Nevalainen, O.; Hakala, T.; Suomalainen, J.M.; Mäkipää, R.; Peltoniemi, M.; Krooks, A.; Kaasalainen, S.

    2014-01-01

    We propose an empirical method for nondestructive estimation of chlorophyll in tree canopies. The first prototype of a full waveform hyperspectral LiDAR instrument has been developed by the Finnish Geodetic Institute (FGI). The instrument efficiently combines the benefits of passive and active remot

  4. Making proteins green: biosynthesis of chlorophyll-binding proteins in cyanobacteria

    Czech Academy of Sciences Publication Activity Database

    Sobotka, Roman

    2014-01-01

    Roč. 119, č. 2 (2014), s. 223-232. ISSN 0166-8595 R&D Projects: GA ČR GAP501/10/1000; GA MŠk ED2.1.00/03.0110 Institutional support: RVO:61388971 Keywords : cyanobacteria * green proteins * chlorophyll * tetrapyrroles Subject RIV: EE - Microbiology, Virology Impact factor: 3.502, year: 2014

  5. Enzyme-catalyzed organic syntheses: transesterification reactions of chlorophyl a, bacteriochlorophyll a, and derivatives with chlorophyllase

    Energy Technology Data Exchange (ETDEWEB)

    Michalski, T.J.; Hunt, J.E.; Bradshaw, C.; Wagner, A.M.; Norris, J.R.; Katz, J.J.

    1988-08-17

    The green plant enzyme chlorophyllase (EC 3.1.1.14, chlorophyll chlorophyllido-hydroase) has been used for the synthesis of a variety of primary alcohol and diol esters of chlorophyll a, bacteriochlorophyll a, and pyrobacteriochlorophyll a. Green plant chlorophyllase accepts a much larger range of alcohol and chlorophyll substrates than had previously been realized. Thus, chlorophyllide and bacteriochlorophyllide esters of primary alcohols such as retinol and the detergent Triton X-100 and of dihydric alcohols such as ethylene glycol, butanediol, or 2-hydroxyethyl disulfide can readily be obtained by enzyme-assisted transesterification. The diol chlorophyllide esters are valuable intermediates for the synthesis of reaction center special pair models. Chlorophyllase-assisted reactions can be carried out in media containing up to 95% of organic solvents without the concomitant side reactions that important chlorophyll functional groups readily undergo even under mild conditions in conventional chemical synthetic procedures. In competitive chlorophyllase-catalyzed transesterification reactions, long-chain alcohols such as farnesol and retinol vs simple aliphatic alcohols and diols, the enzyme shows a definite preference for the long-chain alcohol. 37 references, 1 figure, 2 tables.

  6. Phytol: A chlorophyll component with anti-inflammatory and metabolic properties

    DEFF Research Database (Denmark)

    Olofsson, Peter; Hultqvist, Malin; Hellgren, Lars I.;

    2014-01-01

    The naturally occurring dipterpene molecule Phytol is an alcohol that can be extracted from the chlorophyll of green plants. Phytol has been studied for decades and has been suggested to have both metabolic properties as well as potent anti-inflammatory effects. Phytol represents a molecule derived...

  7. Effect of discharge on the chlorophyll a distribution in the tidally-influenced Potomac River

    Science.gov (United States)

    Bennett, J.P.; Woodward, J.W.; Shultz, D.J.

    1986-01-01

    In the tidal Potomac River, high river discharges during the spring are associated with high chlorophyll a concentrations in the following in the following summer, assuming that summertime light and temperature conditions are favorable. Spring floods deliver large loads of particulate N and P to the tidal river. This particulate N and P could be mineralized by bacteria to inorganic N and P and released to the water column where it is available for phytoplankton use during summertime. However, during the study period relatively low concentrations of chlorophyll a (less than 50 ??g l-1 occurred in the tidal river if average monthly discharge during July or August exceeded 200 m3s-1. Discharge and other conditions combined to produce conditions favorable for nuisance levels of chlorophyll a (greater than 100 ??g l-1 approximately one year out of four. Chlorophyll a maxima occurred in the Potomac River transition zone and estuary during late winter (dinoflagellates) and spring (diatoms). Typical seasonal peak concentrations were achieved at discharges as high as 970 m3 s-1, but sustained discharges greater than 1,100 m3 s-1 retarded development. Optimum growth conditions occurred following runoff events of 10 to 15 d duration which produced transit times to the transition zone of 7 to 10 d. Wet years with numerous moderate-sized runoff events, such as 1980, tend to produce greater biomass in the transition zone and estuary than do dry years such as 1981. ?? 1986 Estuarine Research Federation.

  8. Plankton studies in San Francisco Bay; I, Chlorophyll distributions and hydrographic properties, July 1977-December 1979

    Science.gov (United States)

    Alpine, Andrea E.; Cloern, James E.; Cole, Brian E.

    1981-01-01

    This report summarizes the distribution of phytoplankton biomass and selected hydrographic properties measured in the San Francisco Bay Estuary, on a near-monthly basis, from July 1977 through December 1979. Parameters measured were: chlorophyll a, phaeopigments, in-vivo fluorescence, turbidity, size distribution of phytoplankton, salinity and temperature. (USGS)

  9. Fine mapping of a dominant gene conferring chlorophyll-deficiency in Brassica napus.

    Science.gov (United States)

    Wang, Yankun; He, Yongjun; Yang, Mao; He, Jianbo; Xu, Pan; Shao, Mingquan; Chu, Pu; Guan, Rongzhan

    2016-01-01

    Leaf colour regulation is important in photosynthesis and dry material production. Most of the reported chlorophyll-deficient loci are recessive. The dominant locus is rarely reported, although it may be more important than the recessive locus in the regulation of photosynthesis efficiency. During the present study, we mapped a chlorophyll-deficient dominant locus (CDE1) from the ethyl methanesulfonate-mutagenized Brassica napus line NJ7982. Using an F2 population derived from the chlorophyll-deficient mutant (cde1) and the canola variety 'zhongshuang11', a high-density linkage map was constructed, consisting of 19 linkage groups with 2,878 bins containing 13,347 SNP markers, with a total linkage map length of 1,968.6 cM. Next, the CDE1 locus was mapped in a 0.9-cM interval of chromosome C08 of B. napus, co-segregating with nine SNP markers. In the following fine-mapping of the gene using the inherited F2:3 populations of 620 individuals, the locus was identified in an interval with a length of 311 kb. A bioinformatics analysis revealed that the mapping interval contained 22 genes. These results produced a good foundation for continued research on the dominant locus involved in chlorophyll content regulation. PMID:27506952

  10. The Energy Transfer Processes between Carotenoid and Chlorophyll Regulated by Electron Exchange Mechanism

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The energy transfer efficiency between carotenoids and chlorophyll depend on temperature and viscosity of the media. A 3.5 ps process was detected by the pico-second time-resolved spectra and the process was proved to be regulated by electron exchange mechanism.

  11. Induced mutations in chickpea (Cicer arietinum L.) II. frequency and spectrum of chlorophyll mutations

    International Nuclear Information System (INIS)

    A comparative study of frequency and spectrum of chlorophyll mutations induced by two physical (gamma rays, fast neutrons) and two chemical mutagens (NMU, EMS) in relation to the effects in M1 plants and induction of mutations in M2 was made in four chickpea (Cicer arietinum L.) varieties, two desi (G 130 & H 214) one Kabuli (C 104) and one green seeded (L 345). The treatments included three doses each of gamma rays (400, 500 & 600 Gy) and fast neutrons (5, 10 & 15 Gy) and two concentrations with two different durations of two chemical mutagens, NMU [0.01% (20h), & 0.02% (8h)] and EMS [0.1% (20h) & 0.2% (8h)]. The frequencies and spectrum of three different kinds of induced chlorophyll mutations in the order albina (43.5%), chlorina (27.3%) and xantha (24.2%) were recorded. Chemical mutagens were found to be efficient in inducing chlorophyll mutations in chickpea. Highest frequency of mutations was observed in green seeded var. L 345 (83% of M1 families and 19.9/1000 M2 plants). Kabuli var. C 104 was least responsive for chlorophyll mutations

  12. Predicting chlorophyll content of greenhouse tomato with ground-based remote sensing

    Science.gov (United States)

    Ding, Yong-jun; Li, Min-zan; Li, Shu-qiang; An, Deng-kui

    2010-11-01

    NIR spectroscopy can be used in analysis of plant chlorophyll content on a large scale area. This offers the opportunity to use spectral reflectance as a non-destructive method for analyzing photosynthetic pigment status in plant. This research studied the variation of the chlorophyll content and spectral response at different growth stages of greenhouse tomato. Leaf spectral measurements from each treatment (4 N-levels: 0%, 33.3%, 66.6%, 100%) were taken in the greenhouse using an ASD FieldSpec HH spectrophotometer. Chlorophyll content of tomato leaves were measured by alcoholic-acetone extraction in lab. It was found that chlorophyll content of tomato leaf was increasing continuously to the maximum 50 days after the transplantation, while red edge moved to the NIR bands (long wave), and green peak position moved to the Blue bands (short wave) and green peak amplitude decreased. The chlorophyll content would decrease after fruiting stage, while red edge, green peak position and amplitude moved to the opposite direction. Regarding quantitative analysis the relationship between chlorophyll content and spectral response, red edge parameters (Sred(area of red edge), Dred (amplitude of red edge) and Pred (position of red edge ) ) in the first derivative of reflectance curve were obtained at bands of 680-760 nm. Similarly, blue edge, green peak and red valley parameters were defined to reflect spectral character. Vegetation indices were used extensively to estimate the vegetation growth status. Thus, the following wavelengths were used for developing RVI, NDVI and ARVI indices: λ440nm, λ500nm, λ550nm, λ680nm, λ770nm, Pblue (position of blue edge), Pyellow (position of yellow edge), Pred (position of red edge), Pgreenpeak (position of green peak), Predvalley (position of red valley). Seven optimal spectral parameters were chosen with the method of Karhunen-Loeve from the above-mentioned 68 self-defined property parameters. Stepwise multiple regression (SMLR

  13. Chlorophyll evaluation methods in Brachiaria brizantha brs Piatã added with poultry litter compost

    Directory of Open Access Journals (Sweden)

    Alexandre Antonio Pasqualini

    2013-12-01

    Full Text Available One of the major limitations for pastures high production is the low fertility of tropical soils. In general, the nutrient reposition through chemical fertilizers increases the cost of production and can unbalance the plant besides the environment pollution. Recycling solid residues from agribusiness is a sustainable alternative for farmers. Among the residues, the poultry litter (PL aerobically fermented is a very good bio fertilizer for pastures. The Piatã Grass (Brachiaria brizantha is a new option for the pasture market and can be used for bovine, equine or ovine. The fast diagnosis of the nutritional stage of this plant, based upon portable methods as the Dualex, measuring leaf light reflectance is a practical alternative.  By this way,  it is possible to offer to the herd high nutritional food, correcting eventual shortage, mainly nitrogen. Nitrogen nutrition is directely related to chlorophyll content in the leaf blade. This study aimed to verify the effects of doses of PL over total chlorophyll, in comparison to two methods of evaluation: Dualex Scientific 4.0 and Spectrophotometer Analysis according to Lichtenthaler & Wellburn (1983. The experiment was conducted in greenhouse conditions, at IZ, Nova Odessa, with a Haplortox soil, between May and July, 2013. Treatments consisted of five compost doses (PL: 0, 20, 40, 60 and 120 Mg ha-1, with the following chemical composition (%: 2.88 of N, 3.85 of P2O5, 2.50 of K2O, 9.06 of Ca and 1.16 of Mg. The experimental design was on randomized blocks with five replications. Data were analyzed using the GLM procedure of the SAS program. Chlorophyll data were taken from the third medium of the leaf blade from a third of the expanded leaf from the apical using the Dualex. At the same time, samples were harvested for the Spectrophotometer analyses according to methodology described by Lichtenthaler & Wellburn (1983. Total Chlorophyll amounts were increased with the higher doses of PL, adjusting

  14. Retrieval and Validation of Chlorophyll-a Concentrations in the Coastal Waters Off Yanam and Kakinada (Godavari) Basin Along East Coast of India.

    Digital Repository Service at National Institute of Oceanography (India)

    Latha, T.P.; Nagamani, P.V.; Rao, K.H.; Dash, S.K.; Choudhury, S.B.; Rehman, A.; Sarma, V.V.S.S.; Babu, M.N.; Amarendra, P.; Rao, B.S.; Prasad, T.D.V.

    depth) using Underwater radiometer (Hyperpro-II). In-vivo chlorophyll profiles were collected using wet labs fluorometer integrated with underwater Hyperspectral radiometer. Chlorophyll-a concentrations were estimated using HPLC by collecting the water...

  15. Chlorophyll modulation of mixed layer thermodynamics in a mixed-layer isopycnal general circulation model - An example from Arabian Sea and Equatorial Pacific

    Digital Repository Service at National Institute of Oceanography (India)

    Nakamoto, S.; PrasannaKumar, S.; Oberhuber, J.M.; Saito, H.; Muneyama, K.

    and supported by quasi-steady upwelling. Remotely sensed chlorophyll pigment concentrations from the Coastal Zone Color Scanner (CZCS) are used to investigate the chlorophyll modulation of ocean mixed layer thermodynamics in a bulk mixed-layer model, embedded...

  16. Distribution patterns of bacterioplankton and chlorophyll-a in the German Wadden Sea

    Science.gov (United States)

    Poremba, K.; Tillmann, U.; Hesse, K.-J.

    1999-08-01

    In a first synoptic evaluation, the temporal and spatial distribution of bacterioplankton and chlorophyll-a were determined in the German Wadden Sea. Three surveys were undertaken in winter, spring, and summer of 1994 using up to eight ships simultaneously between the river Ems and Sylt island. Despite intensive hydrodynamic mixing of the Wadden Sea water, spatial gradients were obvious. The abundance of bacterioplankton ranged from 0.4 to 26×105 ml-1 and chlorophyll-a varied between <0.1 and 79 µg l-1. In winter, relatively homogeneous distribution patterns of both parameters with small gradients were found. Highest chlorophyll-a values connected with a highly patchy structure were observed in spring, while in summer both total chlorophyll-a values and the complexity of the distribution pattern had decreased. In contrast, bacterial numbers increased steadily from January to July with the highest bacterial densities and greatest patchiness observed in summer. Moreover, in some regions of the Wadden Sea, a trophic succession of algae as carbon producers and bacteria as consumers was evident. Correlation analysis verified the relationship between bacteria and chlorophyll a, indicating bottom-up control of bacterial abundance in the northern part of the German Wadden Sea. Since the observed regression slope is remarkably low (0.12-0.46) compared to literature values (0.5-0.8), we suggest that the link between phytoplankton and bacteria found here is a special characteristic of the Wadden Sea as a transition zone between the coastal region and the outer North Sea.

  17. Impacts of Organic Macromolecules, Chlorophyll and Soot on Arctic Sea Ice

    Science.gov (United States)

    Ogunro, O. O.; Wingenter, O. W.; Elliott, S.; Flanner, M.; Dubey, M. K.

    2014-12-01

    Recent intensification of Arctic amplification can be strongly connected to positive feedback relating black carbon deposition to sea ice surface albedo. In addition to soot deposition on the ice and snow pack, ice algal chlorophyll is likely to compete as an absorber and redistributor of energy. Hence, solar radiation absorption by chlorophyll and some components of organic macromolecules in/under the ice column is currently being examined to determine the level of influence on predicted rate of ice loss. High amounts of organic macromolecules and chlorophyll are produced in global sea ice by the bottom microbial community and also in vertically distributed layers where substantial biological activities take place. Brine channeling in columnar ice can allow for upward flow of nutrients which leads to greater primary production in the presence of moderate light. Modeling of the sea-ice processes in tandem with experiments and field observations promises rapid progress in enhancing Arctic ice predictions. We are designing and conducting global climate model experiments to determine the impact of organic macromolecules and chlorophyll on Arctic sea ice. Influences on brine network permeability and radiation/albedo will be considered in this exercise. Absorption by anthropogenic materials such as soot and black carbon will be compared with that of natural pigments. We will indicate areas of soot and biological absorption dominance in the sense of single scattering, then couple into a full radiation transfer scheme to attribute the various contributions to polar climate change amplification. The work prepares us to study more traditional issues such as chlorophyll warming of the pack periphery and chemical effects of the flow of organics from ice internal communities. The experiments started in the Arctic will broaden to include Antarctic sea ice and shelves. Results from the Arctic simulations will be presented.

  18. A new chlorophyll d-containing cyanobacterium: evidence for niche adaptation in the genus Acaryochloris.

    Science.gov (United States)

    Mohr, Remus; Voss, Björn; Schliep, Martin; Kurz, Thorsten; Maldener, Iris; Adams, David G; Larkum, Anthony D W; Chen, Min; Hess, Wolfgang R

    2010-11-01

    Chlorophyll d is a photosynthetic pigment that, based on chemical analyses, has only recently been recognized to be widespread in oceanic and lacustrine environments. However, the diversity of organisms harbouring this pigment is not known. Until now, the unicellular cyanobacterium Acaryochloris marina is the only characterized organism that uses chlorophyll d as a major photopigment. In this study we describe a new cyanobacterium possessing a high amount of chlorophyll d, which was isolated from waters around Heron Island, Great Barrier Reef (23° 26' 31.2″ S, 151° 54' 50.4″ E). The 16S ribosomal RNA is 2% divergent from the two previously described isolates of A. marina, which were isolated from waters around the Palau islands (Pacific Ocean) and the Salton Sea lake (California), suggesting that it belongs to a different clade within the genus Acaryochloris. An overview sequence analysis of its genome based on Illumina technology yielded 871 contigs with an accumulated length of 8 371 965 nt. Their analysis revealed typical features associated with Acaryochloris, such as an extended gene family for chlorophyll-binding proteins. However, compared with A. marina MBIC11017, distinct genetic, morphological and physiological differences were observed. Light saturation is reached at lower light intensities, Chl d/a ratios are less variable with light intensity and the phycobiliprotein phycocyanin is lacking, suggesting that cyanobacteria of the genus Acaryochloris occur in distinct ecotypes. These data characterize Acaryochloris as a niche-adapted cyanobacterium and show that more rigorous attempts are worthwhile to isolate, cultivate and analyse chlorophyll d-containing cyanobacteria for understanding the ecophysiology of these organisms. PMID:20505751

  19. Decomposing the effects of ocean warming on chlorophyll a concentrations into physically and biologically driven contributions

    International Nuclear Information System (INIS)

    Recently compiled observational data suggest a substantial decline in the global median chlorophyll a concentration over the 20th century, a trend that appears to be linked to ocean warming. Several modelling studies have considered changes in the ocean’s physical structure as a possible cause, while experimental work supports a biological mechanism, namely an observed increase in zooplankton grazing rate that outpaces phytoplankton production at higher temperatures. Here, we present transient simulations derived from a coupled ocean general circulation and carbon cycle model forced by atmospheric fields under unabated anthropogenic global warming (IPCC SRES A1FI scenario). The simulations account for both physical and biological mechanisms, and can reproduce about one quarter of the observed chlorophyll a decline during the 20th century, when using realistically parameterized temperature sensitivity of zooplankton metabolism (Q10 between 2 and 4) and phytoplankton growth (Q10 ∼ 1.9). Therefore, we have employed and re-calibrated the standard ecosystem model which assumes a lower temperature sensitivity of zooplankton grazing (Q10 = 1.1049) by re-scaling phytoplankton growth rates and zooplankton grazing rates. Our model projects a global chlorophyll a decline of >50% by the end of the 21st century. While phytoplankton abundance and chlorophyll a experience pronounced negative effects, primary production and zooplankton concentrations are less sensitive to ocean warming. Although changes in physical structure play an important role, much of the simulated change in chlorophyll a and productivity is related to the uneven temperature sensitivity of the marine ecosystem. (letter)

  20. Effects of different concentrations of nitrogen and phosphorus on chlorophyll biosynthesis,chlorophyll a fluorescence,and photosynthesis In Larix olgensis seedlings

    Institute of Scientific and Technical Information of China (English)

    Wu Chu; Wang Zhengquan; Sun Hailong; Guo Shenglei

    2006-01-01

    In our experiments,one-year-old Larix olgensis seedlings were cultivated in sand,and supplied with solutions with different concentrations of nitrate or phosphate.The effects of nitrogen and phosphorus supply on chlorophyll biosynthesis,total nitrogen content,and photosynthetic rate were studied.The experimental results are listed below: 1) 5-aminolevulinic acid (ALA) synthetic rate increased as nitrate concentrations supplied to larch seedlings increased from 1 to 8 mmol/L.But the rate decreased by 17% when nitrate concentration increased to 16 mmol/L,in contrast to the control.Under phosphate treatments,ALA synthetic rates were similar to those under nitrate treatments.The activities of porphobilinogen (PBG)synthase reached a maximum when larch seedlings were supplied with 8 mmol/L of nitrate or 1 mmol/L of phosphate.2) When larch seedlings were supplied with 8 mmol/L of nitrate and 0.5 mmol/L of phosphate,the contents of chlorophyll a,chlorophyll b,total chlorophyll,and carotenoids reached a maximum.The total nitrogen contents in leaves increased as nitrate concentrations increased.3) When phosphate concentrations increased from 0.125 to 1 mmol/L,the total nitrogen contents in leaves slightly increased;however,continuous increase of phosphate concentrations resulted in the decrease in total nitrogen contents in leaves.When nitrate concentrations increased from 1 to 8 mmol/L,soluble protein contents in leaves increased in general,and continuous increase of nitrate concentrations induced a decrease in soluble protein contents in leaves.Under treatment of 0.25 mmol/L of phosphate,the soluble protein contents reached a maximum.4) In general,Fv/Fm increased as nitrate concentrations increased from 1 to 8 mmol/L,and continuous increase of nitrate concentration resulted in decrease in FvlFm.The similar changes occurred under phosphate treatments.As nitrate concentrations increased from 1 to 8 mmol/L,photosynthetic rates gradually increased,but when nitrate

  1. Spectral Feature Analysis for Quantitative Estimation of Cyanobacteria Chlorophyll-A

    Science.gov (United States)

    Lin, Yi; Ye, Zhanglin; Zhang, Yugan; Yu, Jie

    2016-06-01

    In recent years, lake eutrophication caused a large of Cyanobacteria bloom which not only brought serious ecological disaster but also restricted the sustainable development of regional economy in our country. Chlorophyll-a is a very important environmental factor to monitor water quality, especially for lake eutrophication. Remote sensed technique has been widely utilized in estimating the concentration of chlorophyll-a by different kind of vegetation indices and monitoring its distribution in lakes, rivers or along coastline. For each vegetation index, its quantitative estimation accuracy for different satellite data might change since there might be a discrepancy of spectral resolution and channel center between different satellites. The purpose this paper is to analyze the spectral feature of chlorophyll-a with hyperspectral data (totally 651 bands) and use the result to choose the optimal band combination for different satellites. The analysis method developed here in this study could be useful to recognize and monitor cyanobacteria bloom automatically and accrately. In our experiment, the reflectance (from 350nm to 1000nm) of wild cyanobacteria in different consistency (from 0 to 1362.11ug/L) and the corresponding chlorophyll-a concentration were measured simultaneously. Two kinds of hyperspectral vegetation indices were applied in this study: simple ratio (SR) and narrow band normalized difference vegetation index (NDVI), both of which consists of any two bands in the entire 651 narrow bands. Then multivariate statistical analysis was used to construct the linear, power and exponential models. After analyzing the correlation between chlorophyll-a and single band reflectance, SR, NDVI respetively, the optimal spectral index for quantitative estimation of cyanobacteria chlorophyll-a, as well corresponding central wavelength and band width were extracted. Results show that: Under the condition of water disturbance, SR and NDVI are both suitable for quantitative

  2. Is It Possible to Distinguish Between Dust and Salt Aerosol Over Waters with Unknown Chlorophyll Concentrations Using Spectral Remote Sensing?

    Science.gov (United States)

    Levy, R. C.; Kaufman, Y. J.

    1999-01-01

    Atmospheric aerosol has uncertain impacts on the global climate system, as well as on atmospheric and bio-geo-chemical processes of regional and local scales. EOS-MODIS is one example of a satellite sensor designed to improve understanding of the aerosols' type, size and distribution at all temporal and spatial scales. Ocean scientists also plan to use data from EOS-MODIS to assess the temporal and spatial coverage of in-water chlorophyll. MODIS is the first sensor planned to observe the combined ocean-atmosphere system with a wide spectral range (from 410 to 2200 nm). Dust aerosol and salt aerosol have similar spectral signals for wavelengths longer than 550 nm, but because dust selectively absorbs blue light, they have divergent signals in the blue wavelength regions (412 to 490 nm). Chlorophyll also selectively absorbs blue radiation, so that varying chlorophyll concentrations produces a highly varying signal in the blue regions, but less variability in the green, and almost no signal in the red to mid-infrared regions. Thus, theoretically, it may be difficult to differentiate dust and salt in the presence of unknown chlorophyll in the ocean. This study attempts to address the cases in which aerosol and chlorophyll signals can and cannot be separated. For the aerosol spectra, we use the aerosol lookup table from the operational MODIS aerosol-over-ocean algorithm, and for chlorophyll spectra, we use the SeaBAM data set (created for SeaWiFS). We compare the signals using Principal Component Analysis and attempt to retrieve both chlorophyll and aerosol properties using a variant of the operational MODIS aerosol-over-ocean algorithm. Results show that for small optical depths, less than 0.5, it is not possible to differentiate between dust and salt and to determine the chlorophyll concentration at the same time. For larger aerosol optical depths, the chlorophyll signals are comparatively insignificant, and we can hope to distinguish between dust and salt.

  3. Energy transfer among CP29 chlorophylls: calculated Förster rates and experimental transient absorption at room temperature.

    Science.gov (United States)

    Cinque, G; Croce, R; Holzwarth, A; Bassi, R

    2000-10-01

    The energy transfer rates between chlorophylls in the light harvesting complex CP29 of higher plants at room temperature were calculated ab initio according to the Förster mechanism (Förster T. 1948, Ann. Physik. 2:55-67). Recently, the transition moment orientation of CP29 chlorophylls was determined by differential linear dichroism and absorption spectroscopy of wild-type versus mutant proteins in which single chromophores were missing (Simonetto R., Crimi M., Sandonà D., Croce R., Cinque G., Breton J., and Bassi R. 1999. Biochemistry. 38:12974-12983). In this way the Q(y) transition energy and chlorophyll a/b affinity of each binding site was obtained and their characteristics supported by reconstruction of steady-state linear dichroism and absorption spectra at room temperature. In this study, the spectral form of individual chlorophyll a and b ligands within the protein environment was experimentally determined, and their extinction coefficients were also used to evaluate the absolute overlap integral between donors and acceptors employing the Stepanov relation for both the emission spectrum and the Stokes shift. This information was used to calculate the time-dependent excitation redistribution among CP29 chlorophylls on solving numerically the Pauli master equation of the complex: transient absorption measurements in the (sub)picosecond time scale were simulated and compared to pump-and-probe experimental data in the Q(y) region on the native CP29 at room temperature upon selective excitation of chlorophylls b at 640 or 650 nm. The kinetic model indicates a bidirectional excitation transfer over all CP29 chlorophylls a species, which is particularly rapid between the pure sites A1-A2 and A4-A5. Chlorophylls b in mixed sites act mostly as energy donors for chlorophylls a, whereas site B5 shows high and bidirectional coupling independent of the pigment hosted. PMID:11023879

  4. The Characterization of Chlorophyll-A and Microalgae Isolation Process of Wastewater Collected at Sembrong Dam

    Science.gov (United States)

    Wellson, R.; Othman, N.; Matias-Peralta, H. M.

    2016-07-01

    Recently, there has been an increasing number of river water quality deterioration that has brought into water quality disruptions that entering dams including in Johor and one of them is occurred in Sembrong Dam in Johor. Sembrong Dam is a major water source for some 120,000 people in the districts of Kluang and parts of Batu Pahat. The quality of water in Sembrong should be well-monitored in ensuring the continuous distribution of clean and safe water supply to peoples. Based on the news reported by The Star news dated on 11 May 2015, the water bodies in Sembrong Dam are polluted by the algae blooms which has started to cause problems in treating water phase by clogging up the filters and causing the production to be reduced and finally resulting in frequent water disruptions to residents. Therefore, there is a need to study the water quality of the dam water prior to further water treatment. One of important characterizations is by measuring chlorophyll-a and the isolation of the dominant microalgae species in the water body in which they are able to indicate the level of water pollution. This paper presents the determination of chlorophyll-a and the isolation of microalgae strains collected from Sembrong Dam. Chlorophyll-a is a photosynthetic pigment present in all species of phytoplankton, including algae and in some photosynthetic bacteria, known as cyanobacteria. The method used in measuring the chlorophyll-a is based on the standard method of IS0 10 260. The average chlorophyll-a concentration measured at Sembrong Dam is 175.9 µg L-1 and it is responsible for the appearance of green color in the sample and it is categorized into hypereutrophic state which is highly polluted. The technique used for isolation of microalgae strains is traditional method which is by spreading the sample on agar. The pure isolate indicated that the genus Botryococcus is the dominant algae species which is characterized morphologically. Both chlorophyll-a and microalgae

  5. Steady-state solutions for subsurface chlorophyll maximum in stratified water columns with a bell-shape vertical profile of chlorophyll

    Directory of Open Access Journals (Sweden)

    X. Gong

    2014-06-01

    Full Text Available A bell-shape vertical profile of chlorophyll a (Chl a concentration, conventionally referred as Subsurface Chlorophyll Maximum (SCM phenomenon, has frequently been observed in stratified oceans and lakes. This profile is assumed to be a general Gaussian distribution in this study. By substituting the general Gaussian function into ecosystem dynamical equations, the steady-state solutions for SCM characteristics (i.e. SCM layer depth, thickness, and intensity in various scenarios are derived. These solutions indicate that: (1 The maximum in Chl a concentrations occurs at or below the depth with the maximum in growth rates of phytoplankton locating at the transition from nutrient limitation to light limitation, and the depth of SCM layer deepens logarithmically with an increase in surface light intensity; (2 The shape of SCM layer (thickness and intensity is mainly influenced by nutrient supply, but independence of surface light intensity; (3 The intensity of SCM layer is proportional to the diffusive flux of nutrient from below, getting stronger as a result of this layer being shrank by a higher light attenuation coefficient or a larger sinking velocity of phytoplankton. The analytical solutions can be useful to estimate environmental parameters difficultly obtained from on-site observations.

  6. Analysis of Chloroplast Ultrastructure, Photosystem Ⅱ Light Harvesting Complexes and Chlorophyll Synthesis in a Chlorophyll-Less Rice Mutant W2555

    Institute of Scientific and Technical Information of China (English)

    XU Pei-zhou; LI Yun; YUAN Shu; ZHANG Hong-yu; WANG Xu-dong; LIN Hong-hui; WU Xian-jun

    2006-01-01

    A comparative study on chloroplast ultrastructure and light harvesting complex of photosystem Ⅱ (LHC Ⅱ) was conducted between a new rice mutant (W2555) and its wild type (WT). The chloroplasts of W2555 had less thylakoids and grana stacks compared with the wild type. There was no significant change in the composition of LHC Ⅱ polypeptide in W2555, while a decline had been noted in LHC Ⅱ content. Northern blot analysis with a specific cab gene probe showed no appreciable difference in the LHC Ⅱ mRNA level between the W2555 and its wild type. The precursors of chlorophyll synthesis, δ-aminolevulinic acid (ALA)and porphobilinogen (PBG) were over accumulated in W2555, but the other precursors were all decreased. These results indicated that the decreased level of LHC Ⅱ in the mutant W2555 was attributed to the change of cab gene transcription, but a blockage in chlorophyll biosynthesis due to the formation of uroporphyrinogen Ⅲ (Urogen Ⅲ).

  7. Steady-state Solutions for Subsurface Chlorophyll Maximum in Stratified Water Columns with a Bell-shape Vertical Profile of Chlorophyll

    Science.gov (United States)

    Gong, X.; Shi, J.; Gao, H.; Yao, X.

    2014-12-01

    A bell-shape vertical profile of chlorophyll a (Chl a) concentration, conventionally referred as Subsurface Chlorophyll Maximum (SCM) phenomenon, has frequently been observed in stratified oceans and lakes. This profile is assumed to be a general Gaussian distribution in this study. By substituting the general Gaussian function into ecosystem dynamical equations, the steady-state solutions for SCM characteristics (i.e. SCM layer depth, thickness, and intensity) in various scenarios are derived. These solutions indicate that: 1) The maximum in Chl a concentrations occurs at or below the depth with the maximum in growth rates of phytoplankton locating at the transition from nutrient limitation to light limitation, and the depth of SCM layer deepens logarithmically with an increase in surface light intensity; 2) The shape of SCM layer (thickness and intensity) is mainly influenced by nutrient supply, but independent of surface light intensity; 3) The intensity of SCM layer is proportional to the diffusive flux of nutrient from below, getting stronger as a result of this layer being shrank by a higher light attenuation coefficient or a larger sinking velocity of phytoplankton. 4) The depth of SCM layer is approximately linear with the nutricine depth, which is inversely proportional to light attenuation coefficient in regions with a low subsurface turbulent diffusivity. The analytical solutions can be useful to estimate environmental parameters which are difficult to observe on site.

  8. Enhancement of Chlorophyll Concentration and Growing Harmful Algal Bloom Along the California Coast

    Science.gov (United States)

    Aceves, Joselyn; Singh, Ramesh

    2016-07-01

    We have carried out detailed analysis of satellite and ground data at different locations, Cal Poly, Goleta, Newport, Santa Monica, and Scripps piers and Monterey, Stearns and Santa Cruz wharfs along the California coast for the period 2008-2015. The sea surface temperature and chlorophyll concentrations derived from satellite data are analyzed together with ground observations of nitrogen, phosphorus, domoic acids and harmful algal blooms. The frequency of harmful algal blooms are found to increase in recent years depending upon the enhancement of chlorophyll concentrations and the discharges along the coast and dynamics of the sea surface temperature. The frequency of harmful algal blooms is higher in the northern California compared to southern California. The anthropogenic activities along the coast have increased which are associated with the forest fires and long range transport of dusts from Asia. The aerosol optical depth derived from satellite data during summer months seems to play an important role in the frequency of harmful algal blooms.

  9. Enhancement of phytoplankton chlorophyll by submesoscale frontal dynamics in the North Pacific Subtropical Gyre

    Science.gov (United States)

    Liu, Xiao; Levine, Naomi M.

    2016-02-01

    Subtropical gyres contribute significantly to global ocean productivity. As the climate warms, the strength of these gyres as a biological carbon pump is predicted to diminish due to increased stratification and depleted surface nutrients. We present results suggesting that the impact of submesoscale physics on phytoplankton in the oligotrophic ocean is substantial and may either compensate or exacerbate future changes in carbon cycling. A new statistical tool was developed to quantify surface patchiness from sea surface temperatures. Chlorophyll concentrations in the North Pacific Subtropical Gyre were shown to be enhanced by submesoscale frontal dynamics with an average increase of 38% (maximum of 83%) during late winter. The magnitude of this enhancement is comparable to the observed decline in chlorophyll due to a warming of ~1.1°C. These results highlight the need for an improved understanding of fine-scale physical variability in order to predict the response of marine ecosystems to projected climate changes.

  10. A new three-band algorithm for estimating chlorophyll concentrations in turbid inland lakes

    Energy Technology Data Exchange (ETDEWEB)

    Duan Hongtao; Ma Ronghua; Zhao Chenlu; Zhou Lin; Shang Linlin [State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing (China); Zhang Yuanzhi [Institute of Space and Earth Information Science, Chinese University of Hong Kong (Hong Kong); Loiselle, Steven Arthur [Dipartimento Farmaco Chimico Tecnologico, CSGI, University of Siena, Siena (Italy); Xu Jingping, E-mail: mrhua2002@niglas.ac.cn [State Key Laboratory of Remote Sensing Science, Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University, Beijing (China)

    2010-10-15

    A new three-band model was developed to estimate chlorophyll-a concentrations in turbid inland waters. This model makes a number of important improvements with respect to the three-band model commonly used, including lower restrictions on wavelength optimization and the use of coefficients which represent specific inherent optical properties. Results showed that the new model provides a significantly higher determination coefficient and lower root mean squared error (RMSE) with respect to the original model for upwelling data from Taihu Lake, China. The new model was tested using simulated data for the MERIS and GOCI satellite systems, showing high correlations with the former and poorer correlations with the latter, principally due to the lack of a 709 nm centered waveband. The new model provides numerous advantages, making it a suitable alternative for chlorophyll-a estimations in turbid and eutrophic waters.

  11. Differentiation between heterotrophic and photosynthetic plankton by size fractionation, glucose uptake, ATP and chlorophyll content

    International Nuclear Information System (INIS)

    By means of a technique which included 3H-D-glucose uptake, ATP and chlorophyll analyses in different size fractions of lake water microorganisms, the bacterial and the phytoplankton biomasses were estimated from four eutrophic lakes. Short term glucose uptake experiments and chlorophyll analyses in lake water used as indicators of the bacteria and the phytoplankton present in the different size fractions, whereas ATP measurements were used to quantify their respective biomasses. The bacteria comprised between 3 and 18% of total biomass (phytoplankton + bacteria) and between 50 and 90% of the bacteria were free-living. The numbers of bacteria calculated from the bacterial ATP content were 20 to 50% higher than the numbers estimated by direct counting. (author)

  12. A new three-band algorithm for estimating chlorophyll concentrations in turbid inland lakes

    International Nuclear Information System (INIS)

    A new three-band model was developed to estimate chlorophyll-a concentrations in turbid inland waters. This model makes a number of important improvements with respect to the three-band model commonly used, including lower restrictions on wavelength optimization and the use of coefficients which represent specific inherent optical properties. Results showed that the new model provides a significantly higher determination coefficient and lower root mean squared error (RMSE) with respect to the original model for upwelling data from Taihu Lake, China. The new model was tested using simulated data for the MERIS and GOCI satellite systems, showing high correlations with the former and poorer correlations with the latter, principally due to the lack of a 709 nm centered waveband. The new model provides numerous advantages, making it a suitable alternative for chlorophyll-a estimations in turbid and eutrophic waters.

  13. Towards a merged satellite and in situ fluorescence ocean chlorophyll product

    Directory of Open Access Journals (Sweden)

    H. Lavigne

    2011-12-01

    Full Text Available Understanding the ocean carbon cycle requires a precise assessment of phytoplankton biomass in the oceans. In terms of numbers of observations, satellite data represents the largest available data set. However, as they are limited to surface waters, they have to be merged with in situ observations. Amongst the in situ data, fluorescence profiles constitute the greatest data set available, because fluorometers operate routinely on oceanographic cruise since the seventies. Nevertheless, fluorescence is only a proxy of the Total Chlorophyll-a concentration and a data calibration is required. Calibration issues are, however, source of uncertainty and they have prevented a systematic and wide range exploitation of the fluorescence data set. In particular, very few attempts to standardize the fluorescence data bases exist. Consequently, merged estimations with other data sources (i.e. satellite are lacking.

    We propose a merging method to fill this gap. It consists firstly, in adjusting the fluorescence profile to impose a zero Chlorophyll-a concentration at depth. Secondly, each point of the fluorescence profile is then multiplied by a correction coefficient which forces the Chlorophyll-a integrated content measured on the fluorescence profile to be consistent with the concomitant ocean color observation. The method is close to the approach proposed by Boss et al. (2008 to calibrate fluorescence data of a profiling float, although important differences do exist. To develop and test our approach, in situ data from three open ocean stations (BATS, HOT and DYFAMED were used. Comparison of the so-called "satellite-corrected" fluorescence profiles with concomitant bottle derived estimations of Chlorophyll-a concentration was performed to evaluate the final error, which resulted to be of about 31 %. Comparison with the Boss et al. (2008 method, carried out on a subset of the DYFAMED data set simulating a profiling float

  14. Towards a merged satellite and in situ fluorescence ocean chlorophyll product

    Directory of Open Access Journals (Sweden)

    H. Lavigne

    2012-06-01

    Full Text Available Understanding the ocean carbon cycle requires a precise assessment of phytoplankton biomass in the oceans. In terms of numbers of observations, satellite data represent the largest available data set. However, as they are limited to surface waters, they have to be merged with in situ observations. Amongst the in situ data, fluorescence profiles constitute the greatest data set available, because fluorometers have operated routinely on oceanographic cruises since the 1970s. Nevertheless, fluorescence is only a proxy of the total chlorophyll a concentration and a data calibration is required. Calibration issues are, however, sources of uncertainty, and they have prevented a systematic and wide range exploitation of the fluorescence data set. In particular, very few attempts to standardize the fluorescence databases have been made. Consequently, merged estimations with other data sources (e.g. satellite are lacking.

    We propose a merging method to fill this gap. It consists firstly in adjusting the fluorescence profile to impose a zero chlorophyll a concentration at depth. Secondly, each point of the fluorescence profile is then multiplied by a correction coefficient, which forces the chlorophyll a integrated content measured on the fluorescence profile to be consistent with the concomitant ocean colour observation. The method is close to the approach proposed by Boss et al. (2008 to correct fluorescence data of a profiling float, although important differences do exist. To develop and test our approach, in situ data from three open ocean stations (BATS, HOT and DYFAMED were used. Comparison of the so-called "satellite-corrected" fluorescence profiles with concomitant bottle-derived estimations of chlorophyll a concentration was performed to evaluate the final error (estimated at 31%. Comparison with the Boss et al. (2008 method, using a subset of the DYFAMED data set, demonstrated that the methods have similar

  15. pH Dependence of Chlorophyll States, Protein Structures and Function of the PSII Membranes

    Institute of Scientific and Technical Information of China (English)

    李冬海; 阮翔; 许强; 王可玢; 公衍道; 匡廷云; 张秀芳; 赵南明

    2003-01-01

    The effect of varying pH on the photosystem II (PSII) membrane was studied using absorption and steady-state fluorescence spectroscopy, and using a variable fluorescence technique.pH variations induced significant changes in the chlorophyll states of the PSII membrane, but no effect was seen on the chlorophyll fluorescence parameter F′v/F′m.For acidic pH conditions, protein structures of the PSII membrane were slightly altered, whilst at alkaline pH levels, large changes in the protein structure of the PSII membrane were detected.The results indicate that the microenvironment around Cys in the PSII membrane is very susceptible to alkaline pH conditions, and that in the acid (4≤pH7) regions, pH variation has no effect on the protein structures of the PSII reaction center (RC).

  16. Um novo clorofilômetro para estimar os teores de clorofila em folhas do capim Tifton 85 A new chlorophyll meter to estimate chlorophyll contents in leaves of Tifton 85 bermudagrass

    Directory of Open Access Journals (Sweden)

    Élio Barbieri Junior

    2012-12-01

    Full Text Available O propósito deste trabalho foi verificar o desempenho de um novo clorofilometro portátil, em parcelas experimentais vegetadas com o capim-Tifton 85 (Cynodon spp.. Para tal, foi utilizado um experimento de curta duração, em que três doses de N (0,75 e 150kg de N ha-1 foram combinadas com quatro datas de amostragem (8, 16, 24 e 28 dias após um corte de uniformização. As análises foram feitas em lâminas da folha mais nova totalmente expandida. Os teores das clorofilas a, b e a+b foram quantificados espectrofotometricamente após a extração com acetona 80%, enquanto que o clorofilômetro forneceu os correspondentes valores de Índice de Clorofila Falker (ICF. As leituras do aparelho foram sensíveis tanto às doses de N quanto às datas de amostragem. Foram obtidas correlações positivas entre ambos os métodos de quantificação (clorofila a: r=0,646; b: r=0,797; e total: r=0,721, que evidenciaram a utilidade desse novo clorofilometro na determinação indireta dos teores de clorofila foliar no capim-Tifton 85.The purpose of this research was to evaluate the performance of a new portable chlorophyll meter in the indirect determination of chlorophyll contents in Tifton 85 bermudagrass leaves. In a field trial of short duration, three N doses (0, 75 and 150kg ha-1 were combined with four sampling dates (8, 16, 24 e 28 days after a cut for sward uniformity in completely randomized blocks, with treatments arranged in a split-plot design. Analyses were performed in the youngest fully expanded leaf blade. Contents of chlorophylls a, b and total were quantified spectrophotometrically, after extraction with acetone 80%, while chlorophyll meter readings, expressed as Falker Chlorophyll Index (FCI units, provided the same information. Chlorophyll meter readings were sensitive to both N rates and sampling dates. It were obtained significant positive correlations between both methods (chlorophyll a: r=0.646, chlorophyll b: r=0.797 and for total

  17. Locality of Chlorophyll-A Distribution in the Intensive Study Area of the Ariake Sea, Japan in Winter Seasons based on Remote Sensing Satellite Data

    Directory of Open Access Journals (Sweden)

    Kohei Arai

    2015-08-01

    Full Text Available Mechanism of chlorophyll-a appearance and its locality in the intensive study area of the Ariake Sea, Japan in winter seasons is clarified by using remote sensing satellite data. Through experiments with Terra and AQUA MODIS data derived chlorophyll-a concentration and truth data of chlorophyll-a concentration together with meteorological data and tidal data which are acquired for 6 years (winter 2010 to winter 2015, it is found that strong correlation between the chlorophyll-a concentration and tidal height changes. Also it is found that the relations between ocean wind speed and chlorophyll-a concentration. Meanwhile, there is a relatively high correlation between sunshine duration a day and chlorophyll-a concentration. Furthermore, it is found that there are different sources of chlorophyll-a in the three different sea areas of Ariake Sea area in the back, Isahaya bay area, and Kumamoto offshore area.

  18. Chlorophyll Reference Conditions for European Lake Types used for Intercalibration of Ecological Status

    OpenAIRE

    Carvalho, L; Solimini, A.; Phillips, G.; van den Berg, M.; Pietilainen, O.-P.; Lyche Solheim, A.; Poikane, S.; MISCHKE U

    2008-01-01

    The Water Framework Directive (WFD), requires European Member States to assess the “ecological status” of surface waters. As part of this, many European countries have developed an ecological quality classification scheme for chlorophyll concentrations as a measure of phytoplankton abundance. The assessment of ecological quality must be based on the degree of divergence of a water body from an appropriate baseline, or ‘reference condition’. It is, therefore, necessary to determine chloroph...

  19. DIFFERENTIAL RESPONSES OF SEVEN CONTRASTING SPECIES TO HIGH LIGHT USING PIGMENT AND CHLOROPHYLL A FLUORESCENCE

    OpenAIRE

    Mittal S; Kumari, N.; Sharma, V.

    2011-01-01

    High light intensity may induce severe photodamage to chloroplast and consequently cause decreases in the yield capacity of plants and destruction of pigments, causing an overall yellowing of the foliage. Thus, study related to light adaptation becomes necessary to understand adaptation processes in higher plants on the basis of which they are characterized as full sunlight or shade plants. Chlorophyll can be regarded as an intrinsic fluorescent probe of the photosynthetic system. The ecophys...

  20. Distribution of nutrients and chlorophyll a in the Three-Gorges Reservoir,China

    Institute of Scientific and Technical Information of China (English)

    LI Chongming; ZHANG Sheng; LIU Jinghong; WEI Shiqiang; ZHANG Yong; GAO Jixi

    2006-01-01

    The Three-Gorges Reservoir (TGR) is one of the largest water conservancy projects in the world. The status of nutrients and phytoplankton biomass has changed since the Three-Gorges Reservoir started water storage on June 1,2003. The distribution features of nutrients and chlorophyll a were deter mined by cruise monitoring during September 8 - 15, 2003. The results showed that the concentrations of dissolved total nitrogen (DTN) range from 1.01 to 1.35 mg · L-1, those of dissolved total phosphorus (DTP) from 0.028 to 0.054 mg · L-1. The concentrations of dissolved nitrogen and phosphorus exceed the eutrophication standards of OECD, and the ratio of DTN to DTP is over 16: 1. It is shown that phos phorus is an eutrophication-limiting element in the water body. The concentrations of potassium range from 2.80 to 3.44 mg · L-1; those of total organic carbon from 1.92 to 2.59 mg · L -1; those of chlorophyll a from 1.58 to 7.53 mg · m-3 with an average value of 4.69 mg · m-3 at surface layer. Atrophic gradient could be observed from the oligotropher to the mesotropher in the flow direction. Phytoplankton biomass in creased significantly in the reservoir area than before. A significant positive correlation (p < 0.05, r = 0. 728 ) between chlorophyll a and NO3-N and a significant negative correlation (p < 0. 01, r = -0.9207) between chlorophyll a and turbidity were also observed. Distribution features could be well divided into three clusters in terms of systematic cluster analyses, including the upper-stream area cluster, the middle stream area cluster and the down-stream area cluster.

  1. MERIS imagery of Belgian coastal waters: mapping of suspended particulate matter and chlorophyll-a

    OpenAIRE

    Ruddick, K.; PARK, Y.; B. Nechad

    2003-01-01

    This paper describes a first application-oriented analysis of MERIS products for Suspended Particulate Matter (SPM) and Chlorophyll-a (CHL) concentration in Belgian coastal waters. Regional algorithms designed for Belgian waters have been implemented and compared with the standard MERIS products, termed Total Suspended Matter and Algal2 respectively. The standard and regional SPM products seem robust and give similar data. Notwithstanding a more complete match-up validation analysis, these pr...

  2. Chlorophyll fluorescence quenching as a tool to screen olive cultivars tolerant to drought stress

    OpenAIRE

    Faraloni, Cecilia; Cutino, Ilaria; Petruccelli, Raffaella; Leva, Anna Rita; Traversi, Maria Laura; Torzillo, Giuseppe

    2009-01-01

    The measurements of fluorescence chlorophyll is considered a promising technique to rapidly quantify the response to physiological stress in higher plants. Drought stress can be considered one of the most frequent environmental constraints causing the failure of newly planted trees. Olive tree (Olea europaea), a representative drought stress tolerant plant, is one of the most typical and economically relevant plant species grown in the Mediterranean area. However, as different cultivars may e...

  3. Photosynthesis monitoring to optimize growth of microalgal mass cultures: application of chlorophyll fluorescence techniques

    Czech Academy of Sciences Publication Activity Database

    Malapascua, José R.F.; Jerez, Celia G.; Sergejevova, Magda; Figueroa, Felix L.; Masojídek, Jiří

    2014-01-01

    Roč. 22, č. 2014 (2014), s. 123-140. ISSN 1864-7790 R&D Projects: GA MŠk ED2.1.00/03.0110; GA MŠk EE2.3.30.0059 Grant ostatní: ACTION(AT) CTM2011-15659-E Institutional support: RVO:61388971 Keywords : chlorophyll * biomass * photosynthesis Subject RIV: EE - Microbiology, Virology Impact factor: 1.258, year: 2014

  4. Chlorophyll fluorescence emission can screen cold tolerance of cold acclimated Arabidopsis thaliana accessions

    Czech Academy of Sciences Publication Activity Database

    Mishra, Anamika; Heyer, A. G.; Mishra, Kumud

    2014-01-01

    Roč. 10, č. 38 (2014). ISSN 1746-4811 R&D Projects: GA MŠk EE2.3.20.0246; GA MŠk 7E12047 Institutional support: RVO:67179843 Keywords : high-throughput screening * chlorophyll a fluorescence transients * cold tolerance * cold acclimation * whole plant * Arabidopsis thaliana Subject RIV: EH - Ecology, Behaviour Impact factor: 3.102, year: 2014

  5. Gas exchanges in peach palms as a function of the spad chlorophyll meter readings

    Directory of Open Access Journals (Sweden)

    Maria Luiza Sant'anna Tucci

    2011-10-01

    Full Text Available The close relationship between the chlorophyll-meters readings and the total chlorophyll and nitrogen contents in leaves, has allowed their evaluation both in annual and perennial species. Besides, some physiological events such as the CO2 assimilation have also been estimated by chlorophyll meters. This work was carried out aiming to evaluate the gas exchanges of peach palms as a function of the chlorophyll SPAD-Meter readings. Three year-old peach palms from Yurimaguas, Peru were studied in Ubatuba, SP, Brazil, spaced 2 x 1 m in area under a natural gradient of organic matter which allowed four plots to be considered, according to the peach palms leaves colors, from light yellow to dark green. The SPAD readings and the stomatal frequency of leaflets were evaluated. The photosynthetic photon flux density (PPFD, μmol m-2 s-1, the leaf temperature (Tleaf, ºC, the CO2 assimilation (A, μmol m-2 s-1, the stomatal conductance (g s, mol m-2 s-1, the transpiration (E, mmol m-2 s-1 and the intercellular CO2 concentration (Ci, μmol mol-1 were evaluated with a portable infrared gas analyzer (LCA-4, ADC BioScientific Ltd., Great Amwell, U.K.. A linear increase in the CO2 assimilation as a function of the SPAD readings (y = -0.34 + 0.19x, R² = 0.99, indicates that they can be a rapid and cheap complementary method to evaluate in peach palms some important physiological events, such as CO2 assimilation.

  6. Retrieval of spruce leaf chlorophyll content from airborne image data using continuum removal and radiative transfer

    Czech Academy of Sciences Publication Activity Database

    Malenovský, Z.; Homolová, L.; Zurita-Milla, R.; Lukeš, Petr; Kaplan, Věroslav; Hanuš, Jan; Gastellu-Etchegory, J.P.; Schaepman, M.E.

    2013-01-01

    Roč. 131, APR (2013), s. 85-102. ISSN 0034-4257 R&D Projects: GA MŠk(CZ) ED1.1.00/02.0073; GA MŠk(CZ) LM2010007 Institutional support: RVO:67179843 Keywords : Chlorophyll retrieval * Imaging spectroscopy * Continuum removal * Radiative transfer * PROSPECT * DART * Optical indices * Norway spruce * High spatial resolution * AISA Subject RIV: EH - Ecology, Behaviour Impact factor: 4.769, year: 2013

  7. Mixed layer variability and chlorophyll a biomass in the Bay of Bengal

    OpenAIRE

    Narvekar, J.; Prasanna Kumar, S.

    2014-01-01

    The mixed layer is the most variable and dynamically active part of the marine environment that couples the underlying ocean to the atmosphere and plays an important role in determining the oceanic primary productivity. We examined the basin-scale processes controlling the seasonal variability of mixed layer depth in the Bay of Bengal and its association with chlorophyll using a suite of in situ as well as remote sensing data. A coupling between mixed layer depth and chlorop...

  8. Chlorophyll increases off the coasts of Japan after the 2011 tsunami using NASA/MODIS data

    OpenAIRE

    E. Sava; Edwards, B; Cervone, G.

    2014-01-01

    Large chlorophyll anomalies are observed after the 2011 Japanese tsunami using the NASA MODIS instrument onboard the TERRA and AQUA satellites. These anomalies are observed both along the eastern coast of Japan, where the tsunami wave hit with maximum force, and in the deep water surrounding the epicentral region. Although both satellites show agreeing spatio-temporal patterns, larger anomalies are detected using the AQUA satellite. A temporal analysis shows increased chloro...

  9. Chlorophyll increases off the coasts of Japan after the 2011 Tsunami using NASA/MODIS data

    OpenAIRE

    E. Sava; Edwards, B; Cervone, G.

    2013-01-01

    Large chlorophyll anomalies are observed after the 2011 Japanese tsunami using the NASA MODIS instrument onboard the TERRA and AQUA satellites. These anomalies are observed both along the Eastern coast of Japan, where the tsunami wave hit with maximum force, and in the deep water surrounding the epicentral region. Although both satellites show agreeing spatio-temporal patterns, larger anomalies are detected using the AQUA satellite. A temporal analysis shows increased chloro...

  10. Effect of drought stress on yield, proline and chlorophyll contents in three chickpea cultivars

    OpenAIRE

    Mafakheri, A.; Siosemardeh, A.; Bahramnejad, B.; Struik, P.C.; Sohrabi, Y. (Yahya)

    2010-01-01

    Drought stress is one of the major abiotic stresses in agriculture worldwide. This study was carried out to investigate the effect of drought stress on proline content, chlorophyll content, photosynthesis and transpiration, stomatal conductance and yield characteristics in three varieties of chickpea (drought tolerant Bivaniej and ILC482 and drought sensitive Pirouz). A field experiment with four irrigation regimes was carried out in a randomized complete block design with three replications....

  11. Near infrared fluorescent chlorophyll nanoscale liposomes for sentinel lymph node mapping

    OpenAIRE

    Fan L; Wu Q; Chu M

    2012-01-01

    Lina Fan,1,* Qiang Wu,1,* Maoquan Chu1,21School of Life Science and Technology, 2The Institute for Advanced Materials and Nano Biomedicine Tongji University, Shanghai, People's Republic of China *These authors contributed equally to this workBackground: Sentinel lymph node (SLN) mapping using in vivo near infrared fluorescence imaging has attracted great attention during the past few years. Here we report on the early use of poorly water-soluble chlorophyll with near infrared fluoresc...

  12. Forest productivity and water stress in Amazonia: observations from GOSAT chlorophyll fluorescence

    OpenAIRE

    J.-E. Lee; C. Frankenberg; C. van der Tol; J. A. Berry; Luis Guanter; C. K. Boyce; J. B. Fisher; E. Morrow; J. R. Worden; S. Asefi; G. Badgley; S. Saatchi

    2013-01-01

    It is unclear to what extent seasonal water stress impacts on plant productivity over Amazonia. Using new Greenhouse gases Observing SATellite (GOSAT) satellite measurements of sun-induced chlorophyll fluorescence, we show that midday fluorescence varies with water availability, both of which decrease in the dry season over Amazonian regions with substantial dry season length, suggesting a parallel decrease in gross primary production (GPP). Using additional SeaWinds Scatterometer onboard Qui...

  13. Deriving sun-induced chlorophyll fluorescence from airborne based spectrometer data

    OpenAIRE

    Damm, A.; Schickling, A.; Schlapfer, D.; M. E. Schaepman; Rascher, U.

    2010-01-01

    Sun-induced chlorophyll fluorescence (Fs) is a promising parameter for remote measuring plant photosynthesis. It has been demonstrated that Fs at cell and leaf level is strongly related to photosynthesis. The transfer of the Fs approach to canopy level remains challenging as the canopy Fs signal is not fully understood yet. Several factors influence the Fs signal and need to be quantified. However, the absence of dedicated imaging spectrometers limits the experimental data for such investigat...

  14. First observations of global and seasonal terrestrial chlorophyll fluorescence from space

    OpenAIRE

    Joiner, J.; A. P. Vasilkov; Y. Yoshida; Corp, L. A.; E. M. Middleton

    2011-01-01

    Remote sensing of terrestrial vegetation fluorescence from space is of interest because it can potentially provide global coverage of the functional status of vegetation. For example, fluorescence observations may provide a means to detect vegetation stress before chlorophyll reductions take place. Although there have been many measurements of fluorescence from ground- and airborne-based instruments, there has been scant information available from satellites. In this work...

  15. Chlorophyll a fluorescence lifetime reveals reversible UV-induced photosynthetic activity in the green algae Tetraselmis

    OpenAIRE

    Kristoffersen, Arne Skodvin; Hamre, Børge; Frette, Øyvind; Erga, Svein Rune

    2015-01-01

    The fluorescence lifetime is a very useful parameter for investigating biological materials on the molecular level as it is mostly independent of the fluorophore concentration. The green alga Tetraselmis blooms in summer, and therefore its response to UV irradiation is of particular interest. In vivo fluorescence lifetimes of chlorophyll a were measured under both normal and UV-stressed conditions of Tetraselmis. Fluorescence was induced by two-photon excitation using a femtosecond laser and ...

  16. Computer Reconstruction of Plant Growth and Chlorophyll Fluorescence Emission in Three Spatial Dimensions

    OpenAIRE

    Ladislav Nedbal; David Šebela; Chandra Bellasio; Radek Tesař; Julie Olejníčková

    2012-01-01

    Plant leaves grow and change their orientation as well their emission of chlorophyll fluorescence in time. All these dynamic plant properties can be semi-automatically monitored by a 3D imaging system that generates plant models by the method of coded light illumination, fluorescence imaging and computer 3D reconstruction. Here, we describe the essentials of the method, as well as the system hardware. We show that the technique can reconstruct, with a high fidelity, the leaf size, the leaf an...

  17. Co-registration of chlorophyll fluorescence emission and 3D models of plants

    Czech Academy of Sciences Publication Activity Database

    Ryba, Tomáš; Železný, Miloš

    Brno : Global change research centre, Academy of Sciences of the Czech Republic, v. v. i, 2013 - (Stojanov, R.; Žalud, Z.; Cudlín, P.; Farda, A.; Urban, O.; Trnka, M.), s. 264-267 ISBN 978-80-904351-8-6. [Global Change and Resilience. Brno (CZ), 22.05.2013-24.05.2013] Institutional support: RVO:67179843 Keywords : chlorophyll fluorescence * 3D model of plant * co- registration * image registration * calibration object Subject RIV: EH - Ecology, Behaviour

  18. Sensitized Triplet Formation of Chlorophyll-A and beta-Carotene

    DEFF Research Database (Denmark)

    Jensen, Nina Mejlhede; Wilbrandt, Robert Walter; Pagsberg, Palle Bjørn

    1980-01-01

    The naphthalene-sensitized formation of triplet excited chlorophyll-a (Chl-a) and all-transß-carotene has been studied by pulse radiolysis. The rate constants for transfer of triplet energy from naphthalene to Chl-a and all-transß-carotene in benzene at 25°C are (3.6 ± 0.6)·109M-1 s-1 and (10.7 ±...

  19. Estimation of single leaf chlorophyll content in sugar beet using machine vision

    OpenAIRE

    MOGHADDAM, Parviz Ahmadi; DERAFSHI, Mohammadali Haddad; SHIRZAD, Vine

    2011-01-01

    Estimating crop nitrogen status accurately during side-dressing operations is essential for effective management of site-specific nitrogen applications. Variable rate technology (VRT) is one of the major operations in precision agriculture to reduce environmental risks and increase fertilizer use efficiency. In the present study, color image analysis was performed to estimate sugar beet leaf chlorophyll status. The experiment was carried out in a phytotron and nitrogen was applied at 6 levels...

  20. Estimation of Spruce Needle-Leaf Chlorophyll Content Based on DART and PARAS Canopy Reflectance Models

    Czech Academy of Sciences Publication Activity Database

    Yáñez-Rausell, L.; Malenovský, Z.; Rautiainen, M.; Clevers, J G P W.; Lukeš, Petr; Hanuš, Jan; Schaepman, M. E.

    2015-01-01

    Roč. 8, č. 4 (2015), s. 1534-1544. ISSN 1939-1404 R&D Projects: GA MŠk(CZ) ED1.1.00/02.0073 Institutional support: RVO:67179843 Keywords : Chlorophyll a plus b estimation * CHRIS-PROBA * coniferous forest * continuum removal * discrete anisotropic radiative transfer model (DART) * needle-leaf * Norway spruce * optical indices * PARAS * PROSPECT * radiative transfer * recollision probability Subject RIV: EH - Ecology, Behaviour Impact factor: 3.026, year: 2014

  1. Beziehungen zwischen den Xanthophyllzyklen und der Biosynthese von Lichtsammelxanthophyllen in Chlorophyll a/c-haltigen Algen

    OpenAIRE

    Lohr, Martin

    2001-01-01

    Zusammenfassung:In Chlorophyll(Chl) a/c-haltigen Algen leisten Xanthophylle einen wesentlichen Beitrag zur Lichtsammlung. Daneben finden sich weitere Xanthophylle, die an einem Schutzmechanismus bei überoptimalem Lichtangebot beteiligt sind, dem sog. Xanthophyllzyklus. Ein Teil der Chl a/c-haltigen Algen besitzt den auch bei Höheren Pflanzen anzutreffenden Violaxanthin/Antheraxanthin/Zeaxanthin-(Vx/Ax/Zx-)Zyklus. In anderen Gruppen wie den Dinophyta, Haptophyta und den Kieselalgen (Bacillario...

  2. Engineered drought tolerance in tomato plants is reflected in chlorophyll fluorescence emission

    Czech Academy of Sciences Publication Activity Database

    Mishra, Kumud; Iannacone, R.; Petrozza, A.; Mishra, Anamika; Armentano, N.; La Vecchia, G.; Trtílek, M.; Cellini, F.; Nedbal, Ladislav

    2012-01-01

    Roč. 182, SI (2012), s. 79-86. ISSN 0168-9452 R&D Projects: GA MŠk OC08055; GA MŠk 2B06068; GA MŠk(CZ) ED1.1.00/02.0073 Institutional support: RVO:67179843 Keywords : Chlorophyll fluorescence * Drought * High-throughput screening * Solanum lycopersicum * Transcription factor * Transgenic plant Subject RIV: EH - Ecology, Behaviour Impact factor: 2.922, year: 2012

  3. SPAD GREENNESS TO ESTIMATE GENOTYPIC VARIATION IN FLAG LEAF CHLOROPHYLL IN SPRING WHEAT UNDER MEDITERRANEAN CONDITIONS

    OpenAIRE

    Celaleddin BARUTCULAR; TOPTAS, Irem; TURKTEN, Hatice; Yildirim, Mehmet; KOC, Mujde

    2015-01-01

    Leaf chlorophyll (Chl) is emphasized as an indicator for photosynthesis in wheat (Triticum aestivum L.). SPAD greenness meters are used to predict extractable Chl, but few studies have evaluated relationships between flag leaf greenness and Chl among wheat genotypes. Sixteen spring wheat genotypes with similar development patterns were studied in eight environments (2 years, 2 irrigation treatments and 2 sowing times) to investigate the precision of the SPAD-502 meter to predict Chl content/c...

  4. Simulations of chlorophyll fluorescence incorporated into the Community Land Model version 4

    OpenAIRE

    Lee, Jung-Eun; Berry, Joseph A.; van der Tol, Christiaan; Yang, Xi; Guanter, Luis; DAMM Alexander; Baker, Ian; Frankenberg, Christian

    2015-01-01

    Several studies have shown that satellite retrievals of solar-induced chlorophyll fluorescence (SIF) provide useful information on terrestrial photosynthesis or gross primary production (GPP). Here, we have incorporated equations coupling SIF to photosynthesis in a land surface model, the National Center for Atmospheric Research Community Land Model version 4 (NCAR CLM4) and have demonstrated its use as a diagnostic tool for evaluating the calculation of photosynthesis, a key process in a lan...

  5. Chlorophyll a Covalently Bonded to Organo-Modified Translucent Silica Xerogels: Optimizing Fluorescence and Maximum Loading

    OpenAIRE

    García-Sánchez, M. A.; I. N. Serratos; R. Sosa; T. Tapia-Esquivel; F. González-García; F. Rojas-González; S. R. Tello-Solís; A. Y. Palacios-Enriquez; J. M. Esparza Schulz; A. Arrieta

    2016-01-01

    Chlorophyll is a pyrrolic pigment with important optical properties, which is the reason it has been studied for many years. Recently, interest has been rising with respect to this molecule because of its outstanding physicochemical properties, particularly applicable to the design and development of luminescent materials, hybrid sensor systems, and photodynamic therapy devices for the treatment of cancer cells and bacteria. More recently, our research group has been finding evidence for the ...

  6. Comparison of Sun-Induced Chlorophyll Fluorescence Estimates Obtained from Four Portable Field Spectroradiometers

    OpenAIRE

    JULITTA Tommaso; Corp, Lawrence; Schickling, Anke; Colombo, Roberto; Rossini, Micol; Burkart, Andreas; COGLIATI Sergio; Davies, Neville; Hom, Milton; Mac Arthur, Alasdair; Middleton, Elizabeth; Rascher, Uwe

    2016-01-01

    Remote Sensing of Sun-Induced Chlorophyll Fluorescence (SIF) is a research field of growing interest because it offers the potential to quantify actual photosynthesis and to monitor plant status. New satellite missions from the European Space Agency, such as the Earth Explorer 8 FLuorescence EXplorer (FLEX) mission—scheduled to launch in 2022 and aiming at SIF mapping—and from the National Aeronautics and Space Administration (NASA) such as the Orbiting Carbon Observatory-2 (OCO-2) sampling m...

  7. Monitoring of Plant Chlorophyll and Nitrogen Status Using the Airborne Imaging Spectrometer AVIS

    OpenAIRE

    Oppelt, Natascha

    2002-01-01

    Airborne hyperspectral remote sensing enables not only spatial monitoring of vegetation cover, but also the derivation of individual plant constituents such as chlorophyll and nitrogen content. These are important parameters for optimised agricultural management on a field basis through the possibility of spatially differentiated fertilisation and for hydrological and vegetation yield modelling. The use of existing airborne imaging spectrometers is cost-intensive. Moreover, it ...

  8. Analysis of chlorophyll pigment concentration in the northern Arabian Sea using remote sensing and GIS

    Digital Repository Service at National Institute of Oceanography (India)

    Thapa, S.

    , and the hysiology of phytoplankton impose fundamental constraints on the rate of uction of a water column (Platt et al., 1984; Gallegos et al., 1990; Kirk, 1996). d T p primary prod 21 CHAPTER 3 INTRODUCTION TO REMOTE SENSING .1 INTRODUCTION emote sensing has... in the chlorophyll pigment concentrations, possible factors that are responsible for the observed variability is also explored through this project work. and results in large fis In order to understand the environmental factor responsible for the distribution an a...

  9. Soil Salinity Alters Growth, Chlorophyll Content, and Secondary Metabolite Accumulation in Catharanthus roseus

    OpenAIRE

    Jaleel, Cheruth Abdul; SANKAR, Beemarao; SRIDHARAN, Ramalingam

    2008-01-01

    The effect of salinity on growth, photosynthetic pigment content, and alkaloid secondary metabolite accumulation were studied in an economically important medicinal plant, Catharanthus roseus (L.) G. Don., under pot culture conditions. Plants were treated with different concentrations of NaCl, (e.g. 50 and 100 mM) 30, 45, 60, and 75 days after sowing (DAS). The plants were uprooted randomly 90 DAS to analyse growth, and chlorophyll and alkaloid content. Salinity affected all the morphological...

  10. Models of fluorescence and photosynthesis for interpreting measurements of solar-induced chlorophyll fluorescence

    OpenAIRE

    van der Tol, C.; Berry, J. A.; P. K. E. Campbell; Rascher, U.

    2014-01-01

    We have extended a conventional photosynthesis model to simulate field and laboratory measurements of chlorophyll fluorescence at the leaf scale. The fluorescence paramaterization is based on a close nonlinear relationship between the relative light saturation of photosynthesis and nonradiative energy dissipation in plants of different species. This relationship diverged only among examined data sets under stressed (strongly light saturated) conditions, possibly caused by differences in xanth...

  11. Recent Progress in Chemical Modifications of Chlorophylls and Bacteriochlorophylls for the Applications in Photodynamic Therapy.

    Science.gov (United States)

    Staron, Jakub; Boron, Bożena; Karcz, Dariusz; Szczygieł, Małgorzata; Fiedor, Leszek

    2015-01-01

    Since photodynamic therapy emerged as a promising cancer treatment, the development of photosensitizers has gained great interest. In this context, the photosynthetic pigments, chlorophylls and bacteriochlorophylls, as excellent natural photosensitizers, attracted much attention. In effect, several (bacterio) chlorophyll-based phototherapeutic agents have been developed and (or are about to) enter the clinics. The aim of this review article is to give a survey of the advances in the synthetic chemistry of these pigments which have been made over the last decade, and which are pertinent to the application of their derivatives as photosensitizers for photodynamic therapy (PDT). The review focuses on the synthetic strategies undertaken to obtain novel derivatives of (bacterio)chlorophylls with both enhanced photosensitizing and tumorlocalizing properties, and also improved photo- and chemical stability. These include modifications of the C- 17-ester moiety, the isocyclic ring, the central binding pocket, and the derivatization of peripheral functionalities at the C-3 and C-7 positions with carbohydrate-, peptide-, and nanoparticle moieties or other residues. The effects of these modifications on essential features of the pigments are discussed, such as the efficiency of reactive oxygen species generation, photostability, phototoxicity and interactions with living organisms. The review is divided into several sections. In the first part, the principles of PDT and photosensitizer action are briefly described. Then the relevant photophysical features of (bacterio)chlorophylls and earlier approaches to their modification are summarized. Next, a more detailed overview of the progress in synthetic methods is given, followed by a discussion of the effects of these modifications on the photophysics of the pigments and on their biological activity. PMID:26282940

  12. An Automated Comparative Observation System for Sun-Induced Chlorophyll Fluorescence of Vegetation Canopies

    OpenAIRE

    Xijia Zhou; Zhigang Liu; Shan Xu; Weiwei Zhang; Jun Wu

    2016-01-01

    Detecting sun-induced chlorophyll fluorescence (SIF) offers a new approach for remote sensing photosynthesis. However, to analyse the response characteristics of SIF under different stress states, a long-term time-series comparative observation of vegetation under different stress states must be carried out at the canopy scale, such that the similarities and differences in SIF change law can be summarized under different time scales. A continuous comparative observation system for vegetation ...

  13. Variation of phytoplankton biomass as Chlorophyll a in Banglang Reservoir, Yala Province

    OpenAIRE

    Reungchai Tansakul; Pimpan Tansakul; Chalinda Ariyadej1

    2008-01-01

    Environmental variables and phytoplankton biomass as chlorophyll a in Banglang Reservoir were investigated. Phytoplankton were collected monthly from May 2000 to April 2001 from four sampling sites including the inflow from Pattani River (from Betong District), the inflow site from Balahala Forest, the middle of the reservoir, and at the spillway that helds the water before drain. Samples were taken at three levels: water surface,10 meter, and 30 meter depth. Physicochemical parameters were r...

  14. Computer Reconstruction of Plant Growth and Chlorophyll Fluorescence Emission in Three Spatial Dimensions

    Czech Academy of Sciences Publication Activity Database

    Bellasio, Ch.; Olejníčková, Julie; Tesař, R.; Šebela, David; Nedbal, Ladislav

    2012-01-01

    Roč. 12, č. 1 (2012), s. 1052-1071. ISSN 1424-8220 R&D Projects: GA ČR GA522/09/1565; GA MŠk(CZ) ED1.1.00/02.0073 Institutional support: RVO:67179843 Keywords : 3D reconstruction * chlorophyll fluorescence imaging * leaf area * leaf angle * plant growth * coded light Subject RIV: EH - Ecology, Behaviour Impact factor: 1.953, year: 2012

  15. Protein and Chlorophyll Contents of Solanum melongena on Diesel Oil Polluted Soil Amended with Nutrient Supplements

    OpenAIRE

    C.O. Akujobi; R.A. Onyeagba; V.O. Nwaugo; N.N. Odu

    2011-01-01

    The study investigated the remediation effect of nutrient amendments of diesel oil polluted soil on protein and chlorophyll contents of eggplant (Solanum melongena). Soil samples were polluted and amended separately with different weights of poultry waste, pig waste, cow dung and inorganic fertilizer. Soil samples were also polluted with diesel oil without amendment to achieve 2, 4, 6, 8 and 10% pollution. Samples were analyzed at two weeks interval for sixteen weeks. The plant protein and ch...

  16. Optimized Merger of Ocean Chlorophyll Algorithms of MODIS-Aqua and VIIRS

    OpenAIRE

    Kahru, M.; Kudela, RM; Anderson, CR; Mitchell, BG

    2015-01-01

    Standard ocean chlorophyll-a (Chla) products from currently operational satellite sensors Moderate Resolution Imaging Spectroradiometer (MODIS) Aqua and Visible Infrared Imager Radiometer Suite (VIIRS) underestimate medium and high in situ Chla concentrations and have approximately 9% bias between each other in the California Current. By using the regional optimization approach of Kahru et al., we minimized the differences between satellite estimates and in situ match-ups as well as between e...

  17. Evaluation of Chlorophyll Content and Fluorescence Parameters as Indicators of Drought Tolerance in Barley

    Institute of Scientific and Technical Information of China (English)

    LI Rong-hua; GUO Pei-guo; Michael Baum; Stefania Grando; Salvatore Ceccarelli

    2006-01-01

    Drought is a major abiotic stress that severely affects food production worldwide. Agronomic and physiological traits associated with drought tolerance are suitable indicators for selection of drought tolerance genotypes to reduce the impact of water deficit on crop yield in breeding program. The objective of this study was to identify indicators related to drought tolerance through analysis of photosynthetic traits in barley (Hordeum vulgare L.). These traits included chlorophyll content, initial fluorescence (Fo), maximum primary yield of photochemistry of pho tosystem Ⅱ (Fv / Fo) and maximum quantum yield of photosystem Ⅱ (Fv/Fm). Four genotypes (Tadmor, Arta, Morocco9-75 and WI2291) variable in drought tolerance were used to investigate the correlation between these traits and drought tolerance. The results reflected that all of these traits were affected negatively in the four genotypes at different levels of post-anthesis drought stress, but the decrease in drought tolerant genotypes was much less than that of drought sensitive genotypes. The results further revealed that the components of the photosynthetic apparatus could be damaged significantly in drought sensitive genotypes, while drought tolerant genotypes were relatively less affected. On the other hand, the values of chlorophyll content, Fo, Fv/Fo and Fv/Fm in drought tolerance genotypes were significantly higher than those in drought sensitive genotypes under drought stress. It was concluded that chlorophyll content, Fo, Fv / Fo and Fv / Fm could be considered as reliable indicators in screening barley germplasm for drought tolerance.

  18. Long-range correlations in remotely sensed chlorophyll in the South China Sea

    Institute of Scientific and Technical Information of China (English)

    ZHAN Haigang; SHI Ping; MAO Qinwen; ZHANG Tonghui

    2006-01-01

    A 8-year time series of 8-day Seaviewing Wide Field-of-view Sensor (SeaWiFS) data,which spans from Oct 1997 to Oct 2005, was used to study the temporal correlations and scaling behaviour of ocean chlorophyll fluctuations in the South China Sea (SCS) by means of detrended fluctuation analysis (DFA). Long-range correlations in chlorophyll fluctuations were detected in almost all the SCS. The scaling exponents vary over a wide range from 0.5 to 1.14, with an average value of 0.79. High values are found in the upwelling regions, such as the northwest of Luzon and the north of Sunda Shelf. Low values occur in the southwest of Luzon, the east of Hainan Island and a majority of the southern SCS. This spatial pattern is considerably different from that of the scaling exponents of the sea surface temperature (SST) time series. It is also demonstrated that SST exhibits more persistence than chlorophyll in almost all the SCS.

  19. Identification and determination of flavonoids, carotenoids and chlorophyll concentration in Cynodon dactylon (L.) by HPLC analysis.

    Science.gov (United States)

    Muthukrishnan, Saradha Devi; Kaliyaperumal, Ashokkumar; Subramaniyan, Annapoorani

    2015-01-01

    Cynodon dactylon (L.) is a potent medicinal plant in the traditional and current Indian medicinal systems. The objective of this research was to find out the levels of flavonoids, carotenoids and chlorophyll b in C. dactylon leaves by high-performance liquid chromatography (HPLC) equipped with a diode array detector. HPLC analysis revealed that total carotenoid and total flavonoid concentration were 62 mg/100 g and 249.1 μg/g, respectively. The mean chlorophyll b was 85.1 mg/100 g in C. dactylon. Among the flavonoids, quercetin (164.7 μg/g) was the major flavonoid followed by kaempferol (48.2 μg/g), rutin (18.4 μg/g), catechin (12.1 μg/g) and myricetin (5.7 μg/g). Of the carotenoids, β-carotene (35.2 mg/100 g) was predominant followed by lutein (17.0 mg/100 g), violaxanthin (5.8 mg/100 g) and zeaxanthin (4.2 mg/100 g). Chlorophyll b concentration was 85.1 mg/100 g in C. dactylon. The results of this investigation should be useful information for further pharmacological studies. PMID:25495959

  20. A Comparison between Local and Global Spaceborne Chlorophyll Indices in the St. Lawrence Estuary

    Directory of Open Access Journals (Sweden)

    Martin A. Montes-Hugo

    2012-11-01

    Full Text Available Spaceborne chlorophyll indices based on red fluorescence (wavelength = 680 nm and water leaving radiance (Lw in the visible spectrum (i.e., 400–700 nm were evaluated in the St Lawrence Estuary (SLE during September of 2011. Relationships between chlorophyll concentration (chl and fluorescence were constructed based on fluorescence line height (FLH measurements derived from a compact laser-based spectrofluorometer developed by ENEA (CASPER and using spectral bands corresponding to the satellite sensor MERIS (MEdium Resolution Imaging Spectrometer. Chlorophyll concentration as estimated from CASPER (chlCASPER was relatively high NE of the MTZ (upper Estuary, and nearby areas influenced by fronts or freshwater plumes derived from secondary rivers (lower estuary. These findings agree with historical shipboard measurements. In general, global chl products calculated from Lw had large biases (up to 27-fold overestimation and 50-fold underestimation with respect to chlCASPER values. This was attributed to the smaller interference of detritus (mineral + organic non-living particulates and chromophoric dissolved organic matter on chlCASPER estimates. We encourage the use of spectrofluorometry for developing and validating remote sensing models of chl in SLE waters and other coastal environments characterized by relatively low to moderate (<10 g·m−3 concentrations of detritus.

  1. Quenching action of monofunctional sulfur mustard on chlorophyll fluorescence: towards an ultrasensitive biosensor.

    Science.gov (United States)

    Kaur, Simerjit; Singh, Minni; Flora, Swaran Jeet Singh

    2013-11-01

    An ultrasensitive fluorimetric biosensor for the detection of chemical warfare agent sulfur mustard (SM) was developed using its monofunctional analogue. SM is a vesicant and a potent chemical threat owing to its direct toxic effects on eyes, lungs, skin and DNA. This work investigates the quenching action of the analyte on chlorophyll fluorescence as elucidated by nuclear magnetic resonance, Fourier transform infrared spectroscopy and mass spectrometry studies suggesting the electrophilic attack of carbonium ion on nitrogens of the porphyrin moiety of chlorophyll. The properties of immobilisation matrix were optimised and scanning electron microscope observations confirmed improvement in pore size of sol-gels by addition of 32 % (v/v) glycerol, a feature enabling enhanced sensitivity towards the analyte. Chlorophyll embedded sol-gel was treated with increasing concentrations of monofunctional SM and the corresponding drop in maximum fluorescence intensity as measured by emission at 673 nm was observed, which varied linearly and had a detection limit of 7.68 × 10(-16) M. The biosensor was found to be 6 orders of magnitude more sensitive than the glass microfibre-based disc biosensor previously reported by us. PMID:23955347

  2. Effectiveness of Chlorophyll Meter Measurement in Winter Wheat at Field Scale Level

    Directory of Open Access Journals (Sweden)

    Lukas Vojtěch

    2014-07-01

    Full Text Available This paper examines the relationship among chlorophyll meter Yara N-Tester readings, nutrition status and growth parameters (leaf area index (LAI, plant height of the winter wheat plants. Data used in this study were collected in 2010 from two fields located in the Czech Republic (area 52 and 38 ha from different farms, both with uniform and conventional crop management. The monitoring of crop stands was done at growth stage BBCH 30 in a regular sampling grid with 150 m distance between points (27 and 18 points. At each sampling point, the plant height, LAI (Delta-T SunScan and the chlorophyll concentration (Yara N-Tester were recorded. Plant samples were taken to analyse the content of main nutrients (N, P, K, Mg, Ca and S. The results of plant analysis showed that both fields were in different nutrition status: one in a correct status and another had a complex nutritional deficit (K, Ca and N. Linear regressions and ANOVA proved that under a multiple nutritional deficit, N-Tester readings responded to the growth of the crop, while in the adequate nutritional conditions the sensitivity of N-Tester to the variation in the nitrogen concentration is lower. The relationships between crop parameters and chlorophyll meter readings are not generalisable and thus the interpretation of N-Tester results has to be done separately for each field.

  3. Transcriptome Analysis of Manganese-deficient Chlamydomonas reinhardtii Provides Insight on the Chlorophyll Biosynthesis Pathway

    Energy Technology Data Exchange (ETDEWEB)

    Lockhart, Ainsley; Zvenigorodsky, Natasha; Pedraza, Mary Ann; Lindquist, Erika

    2011-08-11

    The biosynthesis of chlorophyll and other tetrapyrroles is a vital but poorly understood process. Recent genomic advances with the unicellular green algae Chlamydomonas reinhardtii have created opportunity to more closely examine the mechanisms of the chlorophyll biosynthesis pathway via transcriptome analysis. Manganese is a nutrient of interest for complex reactions because of its multiple stable oxidation states and role in molecular oxygen coordination. C. reinhardtii was cultured in Manganese-deplete Tris-acetate-phosphate (TAP) media for 24 hours and used to create cDNA libraries for sequencing using Illumina TruSeq technology. Transcriptome analysis provided intriguing insight on possible regulatory mechanisms in the pathway. Evidence supports similarities of GTR (Glutamyl-tRNA synthase) to its Chlorella vulgaris homolog in terms of Mn requirements. Data was also suggestive of Mn-related compensatory up-regulation for pathway proteins CHLH1 (Manganese Chelatase), GUN4 (Magnesium chelatase activating protein), and POR1 (Light-dependent protochlorophyllide reductase). Intriguingly, data suggests possible reciprocal expression of oxygen dependent CPX1 (coproporphyrinogen III oxidase) and oxygen independent CPX2. Further analysis using RT-PCR could provide compelling evidence for several novel regulatory mechanisms in the chlorophyll biosynthesis pathway.

  4. Movement influences carambola leaflet chlorophyll fluorescence and temperature under sunny conditions

    International Nuclear Information System (INIS)

    Leaflets of 'Arkin', 'B-10', 'Kary', and 'Sri Kembangan' carambola (Averrhoa carambola L.) trees were restrained in a horizontal position for 3.5 h during midday under full sun conditions to determine the influence of overriding natural leaflet movement on adaxial chlorophyll fluorescence and temperature. Induced chlorophyll fluorescence obtained after 30 minutes of dark adaptation following the period of full sun exposure was affected by leaflet movement. Restrained leaflets exhibited a variable fluorescence (Fv)/peak fluorescence (Fm) of 0.48, while that of unrestrained leaflets was 0.65. Adaxial leaflet temperature of restrained leaflets was 6C higher than that of leaflets that were allowed to move. The influence of leaflet movement on temperature or chlorophyll fluorescence was not different among the four cultivars. However, mean Fv/Fm of 'Kary' and 'Sri Kembangan' was lower than that of 'B-10'. Our results indicate that the ability of carambola to change leaflet angle leads to lower temperature and higher photochemical efficiency than occurs when leaflets are not allowed to move naturally (vertically orient) under full sun conditions

  5. A new relative referencing method for crop monitoring using chlorophyll fluorescence

    Science.gov (United States)

    Norikane, J.; Goto, E.; Kurata, K.; Takakura, T.

    2003-01-01

    The measurement of plant chlorophyll fluorescence has been used for many years as a method to monitor a plant's health status. These types of methods have been mostly relegated to the laboratory. The newly developed Relative Referencing Method allows for the measurement of chlorophyll fluorescence under artificial lighting conditions. The fluorescence signal can be determined by first taking a reference signal measurement, then a second measurement with an additional fluorescence excitation source. The first signal can then be subtracted from the second and the plant's chlorophyll fluorescence due to the second lighting source can be determined. With this simple approach, a photosynthesizing plant can be monitored to detect signs of water stress. Using this approach experiments on tomato plants have shown that it was possible to detect water stress, while the plants were continuously illuminated by fluorescent lamps. This method is a promising tool for the remote monitoring of crops grown in a CELSS-type application. Published by Elsevier Science Ltd on behalf of COSPAR.

  6. Elevated surface chlorophyll associated with natural oil seeps in the Gulf of Mexico

    Science.gov (United States)

    D'Souza, N. A.; Subramaniam, A.; Juhl, A. R.; Hafez, M.; Chekalyuk, A.; Phan, S.; Yan, B.; MacDonald, I. R.; Weber, S. C.; Montoya, J. P.

    2016-03-01

    Natural hydrocarbon seeps occur on the sea floor along continental margins, and account for up to 47% of the oil released into the oceans. Hydrocarbon seeps are known to support local benthic productivity, but little is known about their impact on photosynthetic organisms in the overlying water column. Here we present observations with high temporal and spatial resolution of chlorophyll concentrations in the northern Gulf of Mexico using in situ and shipboard flow-through fluorescence measurements from May to July 2012, as well as an analysis of ocean-colour satellite images from 1997 to 2007. All three methods reveal elevated chlorophyll concentrations in waters influenced by natural hydrocarbon seeps. Temperature and nutrient profiles above seep sites suggest that nutrient-rich water upwells from depth, which may facilitate phytoplankton growth and thus support the higher chlorophyll concentrations observed. Because upwelling occurs at natural seep locations around the world, we conclude that offshore hydrocarbon seeps, and perhaps other types of deep ocean vents and seeps at depths exceeding 1,000 m, may influence biogeochemistry and productivity of the overlying water column.

  7. Effect of xanthophyll composition on the chlorophyll excited state lifetime in plant leaves and isolated LHCII

    Science.gov (United States)

    Johnson, Matthew P.; Zia, Ahmad; Horton, Peter; Ruban, Alexander V.

    2010-07-01

    Xanthophyll excited states have been implicated by transient absorption and two-photon excitation studies in playing a key role in the regulation of photosynthetic light harvesting via photoprotective energy dissipation. For any proposed quenching mechanism to be effective it must reduce the chlorophyll excited state lifetime from 2 ns to ˜0.5-0.4 ns. In the presented study the effect of xanthophyll composition on the chlorophyll excited state lifetime in Arabidopsis leaves in the light harvesting ( F m) and photoprotective (NPQ) states was determined. The data was compared to the chlorophyll excited state lifetime of native isolated LHCII and CP26 in detergent micelles with varying xanthophyll composition. It was found that although the differences in xanthophyll composition between LHC complexes from various Arabidopsis mutants were sufficient to explain the varying F m lifetime (and varying PSII efficiency), they were not of a sufficient scale to fully explain the observed differences in the NPQ lifetimes. Only when the LHC complexes were exposed to a low detergent/low pH media, a condition known to mimic the conformational state of LHCII associated with NPQ in vivo, were variations in excited state lifetime large enough to explain the differences observed in leaves. Furthermore, the data reveal that the replacement of lutein by either zeaxanthin or violaxanthin in the internal xanthophyll binding sites of LHCII and CP26 reduces the efficiency of energy dissipation in the photoprotective state in leaves and isolated complexes.

  8. A High Efficiency Chlorophyll Sensitized Solar Cell with Quasi Solid PVA Based Electrolyte

    Directory of Open Access Journals (Sweden)

    H. C. Hassan

    2016-01-01

    Full Text Available The objective of this work is to investigate the performance of chlorophyll sensitized solar cells (CSSCs with gel electrolyte based on polyvinyl alcohol (PVA with single iodide salt (potassium iodide (KI and double salt (KI and tetrapropylammonium iodide (TPAI. Chlorophyll was extracted from the bryophyte Hyophila involuta. The CSSC with electrolyte containing only KI salt produced a short circuit current density (Jsc of 4.59 mA cm−2, open circuit voltage (Voc of 0.61 V, fill factor (FF of 0.64, and efficiency (η of 1.77%. However, the CSSC with double salt electrolyte exhibited Jsc of 5.96 mA cm−2, Voc of 0.58 V, fill factor FF of 0.58, and η of 2.00%. Since CSSC with double salt electrolyte showed better efficiency, other cells fabricated will use the double salt electrolyte. On addition of 0.7 M tetrabutyl pyridine (TBP to the double salt electrolyte, the cell’s efficiency increased to 2.17%, Jsc=5.37 mA cm−2, Voc=0.55 V, and FF = 0.73. With 5 mM chenodeoxycholic acid (CDCA added to the chlorophyll, the light to electricity efficiency increased to 2.62% with Jsc of 8.44 mA cm−2, Voc of 0.54 V, and FF of 0.58.

  9. Chlorophyll concentration profiles from in situ radiances by ant colony optimization

    Energy Technology Data Exchange (ETDEWEB)

    Souto, R P [Instituto de Informatica, Universidade Federal do Rio Grande do Sul (UFRGS), Av. Bento Gonalves, 9500, P. O. Box 15064, 91501-970, Porto Alegre, RS (Brazil); Velho, H F Campos; Stephany, S [Laboratorio Associado de Computacao e Matematica Aplicada (LAC), Instituto Nacional de Pesquisas Espaciais (INPE), P. O. Box 515, 12245-970, Sao Jose dos Campos, SP (Brazil); Kampel, M [Divisao de Sensoriamento Remoto (DSR), Instituto Nacional de Pesquisas Espaciais (INPE), P. O. Box 515, 12245-970, Sao Jose dos Campos, SP (Brazil)], E-mail: rpsouto@inf.ufrgsbr, E-mail: haroldo@lac.inpe.br, E-mail: stephan@lac.inpe.br, E-mail: milton@dsr.inpe.br

    2008-07-15

    A methodology for the reconstruction of vertical profiles of the absorption (a) and scattering (b) coefficients in natural waters is presented. Reconstruction is performed using single-wavelength in situ radiance measurements at several depths. The depth is discretized by a multi-region approach assuming that absorption and scattering coefficients are constant in each region. The inverse problem is iteratively computed employing the radiative transfer equation as direct model, and bio-optical models to correlate the chlorophyll concentration to these coefficients. At every iteration, the inverse solver generates a candidate solution that is a set of discrete chlorophyll concentration values. For each region, the concentration is mapped to the values of absorption and scattering coefficients. The radiative transfer equation is then solved by a parallel version of the Laplace transform discrete ordinate (LTSN) method considering polar and azimuthal scattering angles. An objective function is given by the square difference between reconstructed and experimental radiances. In order to compensate the nearly exponential radiance decay with depth, that unbalances the influence of the radiance at different depths, a depth correction factor is applied to weight radiance values at each level. This objective function is minimized by an Ant Colony System (ACS) implementation. A new regularization scheme pre-selects candidate solutions based on their smoothness quantified by the Tikhonov's norm. A new chlorophyll candidate profile is then generated and iterations proceed. Synthetic and real data show the suitability of the proposed method.

  10. Photosynthesis rate, chlorophyll content and initial development of physic nut without micronutrient fertilization

    Directory of Open Access Journals (Sweden)

    Elcio Ferreira dos Santos

    2013-10-01

    Full Text Available Few studies in Brazil have addressed the need for micronutrients of physic nut focusing on physiological responses, especially in terms of photosynthesis. The objective of this study was to evaluate the effects of omission of boron (B, copper (Cu, iron (Fe, manganese (Mn and zinc (Zn on Jatropha curcas L.. The experimental design was a randomized block with four replications. The treatments were complete solution (control and solution without B, Cu, Fe, Mn, and Zn. We evaluated the chlorophyll content (SPAD units, photosynthetic rate, dry matter production and accumulation of micronutrients in plants, resulting from different treatments. The first signs of deficiency were observed for Fe and B, followed by Mn and Zn, while no symptoms were observed for Cu deficiency. The micronutrient omission reduced the dry matter yield, chlorophyll content and photosynthetic rate of the plants differently for each omitted nutrient. It was, however, the omission of Fe that most affected the development of this species in all parameters evaluated. The treatments negatively affected the chlorophyll content, evaluated in SPAD units, and the photosynthetic rate, except for the omission of B. However this result was probably due to the concentration effect, since there was a significant reduction in the dry matter production of B-deficient plants.

  11. Non-radiative relaxation of photoexcited chlorophylls: theoretical and experimental study

    Science.gov (United States)

    Bricker, William P.; Shenai, Prathamesh M.; Ghosh, Avishek; Liu, Zhengtang; Enriquez, Miriam Grace M.; Lambrev, Petar H.; Tan, Howe-Siang; Lo, Cynthia S.; Tretiak, Sergei; Fernandez-Alberti, Sebastian; Zhao, Yang

    2015-09-01

    Nonradiative relaxation of high-energy excited states to the lowest excited state in chlorophylls marks the first step in the process of photosynthesis. We perform ultrafast transient absorption spectroscopy measurements, that reveal this internal conversion dynamics to be slightly slower in chlorophyll B than in chlorophyll A. Modeling this process with non-adiabatic excited state molecular dynamics simulations uncovers a critical role played by the different side groups in the two molecules in governing the intramolecular redistribution of excited state wavefunction, leading, in turn, to different time-scales. Even given smaller electron-vibrational couplings compared to common organic conjugated chromophores, these molecules are able to efficiently dissipate about 1 eV of electronic energy into heat on the timescale of around 200 fs. This is achieved via selective participation of specific atomic groups and complex global migration of the wavefunction from the outer to inner ring, which may have important implications for biological light-harvesting function.

  12. SPATIAL AND TEMPORAL ANALYSIS OF SEAWIFS CHLOROPHYLL IN THE SOUTH TROPICAL PACIFIC OCEAN

    Directory of Open Access Journals (Sweden)

    C Dupouy

    2004-01-01

    Full Text Available The South West Tropical Pacific (SWTP is generally considered as an N-limiting oligotrophic area with parts characterized by permanent deep thermocline and nutricline as the Melanesian Archipelago. However, ocean color imagery shows in this region a strong seasonal chlorophyll cycle, with large blooms which have for long been attributed to nitrogen-fixing cyanobacteria as Trichodesmium. SeaWiFS surface chlorophyll analysis of the area between 5°S-25°S, 150°E-170°W has been conducted from 1997 to 2004. A strong seasonal and interannual variability is described, which relates well with the sea-truth measured chlorophyll concentrations. An empirical orthogonal function analysis helped in determining principal explicative factors of this variability, and in identifying different patterns, i.e., seasonality (austral winter and summer blooms, which may be driven by different fertilization processes, and a unexplained interannual variability. This work represents part of the French PROOF-IRD DIAPAZON (DIAzotrophy in a PAcific ZONe program aiming at estimating nitrogen and carbon fixation by cyanobacteria at the SWTP scale

  13. Indirect Estimations of Lentil Leaf and Plant N by SPAD Chlorophyll Meter

    Directory of Open Access Journals (Sweden)

    Hossein Zakeri

    2015-01-01

    Full Text Available A Soil Plant Analysis Development (SPAD chlorophyll meter can be used to screen for leaf nitrogen (N concentration in breeding programs. Lentil (Lens culinaris L. cultivars were grown under varied N regimes, SPAD chlorophyll meter readings (SCMR were recorded from the cultivars leaves, and leaf N concentration was measured by combustion. Linear regression and the nonlinear Radial Basis Functions (RBF neural networks models were employed to estimate leaf N concentration (LNC based on the SCMR values. The closest estimates of LNC were obtained from the multivariate models in which the combination of plant age, leaf thickness, and SCMR was employed as the independent variable. In comparison, SCMR as the single independent variable in both models estimated less than 50% of LNC variations. The results showed significant effects of soil moisture and plant age on the association of LNC –SCMR as well as the relationship of LNC with plant N, grain yield, and days to maturity. However, the effect of cultivar on the measured variables was negligible. Although lentil N can be diagnosed by comparing SCMR values of the crop with those from a well-fertilized (N fixing plot, the results did not support using SPAD chlorophyll meter for screening lentil LNC.

  14. Assessment of the impact of chlorophyll derivatives to control parasites in aquatic ecosystems.

    Science.gov (United States)

    Erzinger, Gilmar Sidnei; Souza, Suellen Carolina; Pinto, Luciano Henrique; Hoppe, Roberto; Del Ciampo, Lineu Fernando; Souza, Ozair; Correia, Cláudia Hack Gumz; Häder, Donat-Peter

    2015-05-01

    Several research groups have studied new biopesticides which are less toxic to the environment and capable of controlling the vectors of parasitic diseases, especially in aquatic ecosystems. Pest control by photodynamic substances is an alternative to chemical or other measures, with chlorophyll and its derivatives as the most studied substances supported by their easy availability and low production costs. The impact of chlorophyll derivatives on four different species, a small crustacean (Daphnia similis), a unicellular alga (Euglena gracilis) and two species of fish (Astyanax bimaculatus and Cyprynus carpio) were tested under short-term conditions. In addition, the effects of long-term exposure were evaluated in D. similis and E. gracilis. In short-term tests, mortality of D. similis (EC50 = 7.75 mg/L) was most strongly affected by chlorophyllin, followed by E. gracilis (EC50 = 12.73 mg/L). The fish species showed a greater resistance documented by their EC50 values of 17.58 and 29.96 mg/L in C. carpio and A. bimaculatus, respectively. A risk quotient is calculated by dividing an estimate of exposure by an estimate of effect. It indicated that chlorophyll derivatives can be applied in nature to control the vectors of parasitic diseases under short-term conditions, but long-term exposure requires new formulations. PMID:25750014

  15. Chlorophyll concentration profiles from in situ radiances by ant colony optimization

    International Nuclear Information System (INIS)

    A methodology for the reconstruction of vertical profiles of the absorption (a) and scattering (b) coefficients in natural waters is presented. Reconstruction is performed using single-wavelength in situ radiance measurements at several depths. The depth is discretized by a multi-region approach assuming that absorption and scattering coefficients are constant in each region. The inverse problem is iteratively computed employing the radiative transfer equation as direct model, and bio-optical models to correlate the chlorophyll concentration to these coefficients. At every iteration, the inverse solver generates a candidate solution that is a set of discrete chlorophyll concentration values. For each region, the concentration is mapped to the values of absorption and scattering coefficients. The radiative transfer equation is then solved by a parallel version of the Laplace transform discrete ordinate (LTSN) method considering polar and azimuthal scattering angles. An objective function is given by the square difference between reconstructed and experimental radiances. In order to compensate the nearly exponential radiance decay with depth, that unbalances the influence of the radiance at different depths, a depth correction factor is applied to weight radiance values at each level. This objective function is minimized by an Ant Colony System (ACS) implementation. A new regularization scheme pre-selects candidate solutions based on their smoothness quantified by the Tikhonov's norm. A new chlorophyll candidate profile is then generated and iterations proceed. Synthetic and real data show the suitability of the proposed method

  16. Eddy and deep chlorophyl maximum response to wind-shear in the lee of Gran Canaria

    Science.gov (United States)

    Basterretxea, G.; Barton, E. D.; Tett, P.; Sangrá, P.; Navarro-Perez, E.; Arístegui, J.

    2002-06-01

    The physical and biological properties of the warm wake of Gran Canaria were examined during a survey carried out in June 1998. The sampling region was dominated by the presence of a warm triangular region downwind the island and an anticyclonic eddy spun off the island. Convergent and divergent frontal regions were generated by the wind shear zones extending along either side of the sheltered region of the warm wake. With increasing distance from shore, evidence of convergent/divergent frontal regions weakened, but the influence of the eddy increased. Both structures, frontal regions and the eddy, clearly altered the vertical phytoplankton biomass distribution as indicated by chlorophyll-fluorescence. Downwelling on the convergent boundary moved the 26.2 kg m -3 isopycnal and its associated deep chlorophyll maximum (DCM) below the 1% light zone. Upwelling at the divergent boundary not only elevated the DCM with its associated isopycnal but also, because of the increased light levels, allowed a shift in the DCM to higher (deeper) density surfaces (26.4 kg m -3). However, the highest integrated chlorophyll occurred in the central wake.

  17. Revisiting the chlorophyll biosynthesis pathway using genome scale metabolic model of Oryza sativa japonica.

    Science.gov (United States)

    Chatterjee, Ankita; Kundu, Sudip

    2015-01-01

    Chlorophyll is one of the most important pigments present in green plants and rice is one of the major food crops consumed worldwide. We curated the existing genome scale metabolic model (GSM) of rice leaf by incorporating new compartment, reactions and transporters. We used this modified GSM to elucidate how the chlorophyll is synthesized in a leaf through a series of bio-chemical reactions spanned over different organelles using inorganic macronutrients and light energy. We predicted the essential reactions and the associated genes of chlorophyll synthesis and validated against the existing experimental evidences. Further, ammonia is known to be the preferred source of nitrogen in rice paddy fields. The ammonia entering into the plant is assimilated in the root and leaf. The focus of the present work is centered on rice leaf metabolism. We studied the relative importance of ammonia transporters through the chloroplast and the cytosol and their interlink with other intracellular transporters. Ammonia assimilation in the leaves takes place by the enzyme glutamine synthetase (GS) which is present in the cytosol (GS1) and chloroplast (GS2). Our results provided possible explanation why GS2 mutants show normal growth under minimum photorespiration and appear chlorotic when exposed to air. PMID:26443104

  18. AVIRIS spectra correlated with the chlorophyll concentration of a forest canopy

    Science.gov (United States)

    Kupiec, John; Smith, Geoffrey M.; Curran, Paul J.

    1993-01-01

    Imaging spectrometers have many potential applications in the environmental sciences. One of the more promising applications is that of estimating the biochemical concentrations of key foliar biochemicals in forest canopies. These estimates are based on spectroscopic theory developed in agriculture and could be used to provide the spatial inputs necessary for the modeling of forest ecosystem dynamics and productivity. Several foliar biochemicals are currently under investigation ranging from those with primary absorption features in visible to middle infrared wavelengths (e.g., water, chlorophyll) to those with secondary to tertiary absorption features in this part of the spectrum (e.g., nitrogen, lignin). The foliar chemical of interest in this paper is chlorophyll; this is a photoreceptor and catalyst for the conversion of sunlight into chemical energy and as such plays a vital role in the photochemical synthesis of carbohydrates in plants. The aim of the research reported here was to determine if the chlorophyll concentration of a forest canopy could be correlated with the reflectance spectra recorded by the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS).

  19. Growth, chlorophyll content and combined output value in eggplant/garlic relay intercropping systems

    International Nuclear Information System (INIS)

    A plastic tunnel experiment was conducted to investigate the effect of eggplant/garlic relay intercropping on the eggplant growth, chlorophyll content and combined output value in 2011 and 2012. The experimental design was randomized block with three replications consisting of eggplant monoculture (CK), eggplant relay intercropping with normal garlic (NG) and eggplant relay intercropping with green garlic (GG). It is showed that the eggplant stem in 2011 was first thicker then thinner in CK than NG, and it was always thicker in CK than GG; the plant height and stem diameter were both higher in relay intercropping treatments than CK in 2012. The chlorophyll content and chlorophyll a/b ratio were lower in NG compared with CK in most cases. In 2011, the eggplant yield and combined output value in GG were lower than CK, but in 2012, they were higher and the difference of combined output value between GG and CK was significant; for NG, they were always promoted both in 2011 and 2012. Different results between 2011 and 2012 may be due to the different time of green garlic uprooted in the spring. It is proved that uprooting green garlic before eggplant transplanting in 2012 was better to eggplant growth than uprooting them after eggplant transplanting in 2011. The conclusions are drawn that relay intercropping with normal or green garlic can improve the eggplant growth, increase the yield and the combined output value. As a result, eggplant/garlic relay intercropping systems may contribute to sustainable production of eggplant. (author)

  20. Protein and Chlorophyll Contents of Solanum melongena on Diesel Oil Polluted Soil Amended with Nutrient Supplements

    Directory of Open Access Journals (Sweden)

    C.O. Akujobi

    2011-09-01

    Full Text Available The study investigated the remediation effect of nutrient amendments of diesel oil polluted soil on protein and chlorophyll contents of eggplant (Solanum melongena. Soil samples were polluted and amended separately with different weights of poultry waste, pig waste, cow dung and inorganic fertilizer. Soil samples were also polluted with diesel oil without amendment to achieve 2, 4, 6, 8 and 10% pollution. Samples were analyzed at two weeks interval for sixteen weeks. The plant protein and chlorophyll were affected adversely by the diesel oil pollution and the higher the level of pollution, the more the effect. The nutrient amendments were able to remedy the effect of the diesel oil pollution. The remediation effect was nutrient weight dependent and the best remediation effect was observed in poultry waste amended samples. This study has shown that diesel oil contaminated soil may have adverse effect on the protein and chlorophyll contents of plants, but this can be remedied by addition of organic nutrient supplements especially poultry waste.

  1. Characterisation of chlorophyll oxidation mediated by peroxidative activity in olives (Olea europaea L.) cv. Hojiblanca.

    Science.gov (United States)

    Vergara-Domínguez, Honorio; Roca, María; Gandul-Rojas, Beatriz

    2013-08-15

    The oxidation of chlorophyll a (chl a) catalysed by peroxidase (POD) from mesocarp of the olive fruit (Olea europaea L., cv Hojiblanca) in the presence of H2O2 and 2,4-dichlorophenol (2,4-DCP), is characterised via the individualised quantification of the products of the enzymatic reaction using a new methodology of HPLC-UV spectrometry. This innovation has allowed the discovery that, in addition to 13(2) OH chl a and 15(1) OH lactone chl a, which are the first products of POD on chl a, the reaction process sequentially creates another series of oxidised chlorophyll derivatives which have not been previously described. Their origins have been linked to POD activity in the presence of 2,4-DCP. Likewise, a study of the effect of the concentration of the various cosubstrates on the POD reaction rate demonstrated that the correct establishment of the relative concentrations of the same ([H2O2]/[2,4-DCP]/[Chl]=1:3:0.02) is crucial to explaining inhibition effects by substrates and carrying out optimum measurements. Therefore, new essential parameters for the determination of POD activity on a chlorophyll substrate are established. PMID:23561174

  2. Spatiotemporal chlorophyll-a dynamics on the Louisiana continental shelf derived from a dual satellite imagery algorithm

    Science.gov (United States)

    A monthly time series of remotely sensed chlorophyll-a (Chlars) over the Louisiana continental shelf (LCS) was developed and examined for its relationship to river discharge, nitrate concentration, total phosphorus concentration, photosynthetically available radiation (PAR), wind...

  3. Rapid assessment of different oxygenic phototrophs and single-cell photosynthesis with multicolour variable chlorophyll fluorescence imaging

    DEFF Research Database (Denmark)

    Trampe, Erik Christian Løvbjerg; Kolbowski, J.; Schreiber, U.;

    2011-01-01

    We present a new system for microscopic multicolour variable chlorophyll fluorescence imaging of aquatic phototrophs. The system is compact and portable and enables microscopic imaging of photosynthetic performance of individual cells and chloroplasts using different combinations of blue, green...

  4. Response of the equatorial Pacific to chlorophyll pigment in a mixed layer isopycnal ocean general circulation model

    Digital Repository Service at National Institute of Oceanography (India)

    Nakamoto, S.; PrasannaKumar, S.; Oberhuber, J.M.; Ishizaka, J.; Muneyama, K.; Frouin, R.

    pigment concentration from the Coastal Zone Color Scanner (CZCS). In the equatorial Pacific heat accumulation due to a higher abundance of chlorophyll pigments in the equatorial Pacific leads to a decrease of the mixed layer thickness. This generates...

  5. Filtering remotely sensed chlorophyll concentrations in the Red Sea using a space-time covariance model and a Kalman filter

    KAUST Repository

    Dreano, Denis

    2015-04-27

    A statistical model is proposed to filter satellite-derived chlorophyll concentration from the Red Sea, and to predict future chlorophyll concentrations. The seasonal trend is first estimated after filling missing chlorophyll data using an Empirical Orthogonal Function (EOF)-based algorithm (Data Interpolation EOF). The anomalies are then modeled as a stationary Gaussian process. A method proposed by Gneiting (2002) is used to construct positive-definite space-time covariance models for this process. After choosing an appropriate statistical model and identifying its parameters, Kriging is applied in the space-time domain to make a one step ahead prediction of the anomalies. The latter serves as the prediction model of a reduced-order Kalman filter, which is applied to assimilate and predict future chlorophyll concentrations. The proposed method decreases the root mean square (RMS) prediction error by about 11% compared with the seasonal average.

  6. Sterile measurement on the characteristics of chlorophyll fluorescence in plantlets in vitro preserved under low temperature condition

    Science.gov (United States)

    Wu, Yanyou; Xing, Deke

    Micro-environment such as temperature influenced the growth and quality of plantlets in vitro. Chlorophyll fluorescence (ChlF) parameter is an important one for photosynthesis capacity in plant. The modulated chlorophyll fluorescence imaging system can be used for obtaining ChlF imaging and signal of plantlet in vitro because the container has light permeability. Therefore, the biological activity and growth condition of plantlet in vitro can be estimated by sterilely measuring the characteristics of chlorophyll fluorescence. This study determined the parameter of chlorophyll fluorescence in Orychophragmus violaceus plantlets in vitro preserved under different temperature levels (0, 4, and 8°C). The results showed that photosynthesis capacity in Orychophragmus violaceus plantlets in vitro preserved under 4°C condition were higher than that under 0°C or 8°C conditions. The plantlets in vitro preserved under 4°C condition maintained a high vitality to be subcultured.

  7. Influence of single and combination treatments of physical and chemical mutagen on chlorophyll mutations in Finger Millet

    International Nuclear Information System (INIS)

    Gamma rays, ethyl methane sulfonate (EMS) and their combined treatments influenced differently in producing chlorophyll mutations. A good number of chlorophyll mutants with varied frequencies were recorded in M2 generation. The frequency of chlorophyll mutants was higher at lower doses of gamma rays, EMS and their combination treatments. The most frequently observed mutant was Albino type. The other chlorophyll mutants isolated were Xantha, Viridis, Striata and Tigrina. The frequency of tigrina and striata was lowest in variety A-404 and Hr-374, respectively. The efficiency and effectiveness was high at the lower doses of mutagens in both the varieties. EMS (0.2%) was more effective than the corresponding lower dose of gamma rays for both the varieties. (author). 10 refs., 4 tabs

  8. Influence of lecithin liposomes on chlorophyllase-catalyzed chlorophyll hydrolysis. Comparison of intramembraneous and solubilized Phaeodactylum chlorophyllase

    OpenAIRE

    Terpstra, Willemke

    1980-01-01

    1. 1. Chlorophyllase-catalyzed chlorophyll hydrolysis is greatly enhanced by the addition of divalent cations (Mg2+) combined with a reducing agent (dithiothreitol, ascorbate). A similar effect is obtained by the addition of lecithin. In the presence of lecithin, dithiothreitol has only slight or no influence on chlorophyll hydrolysis. Mg2+ eliminates the activating effect of lecithin. 2. 2. In the absence of Mg2+ + dithiothreitol or of lecithin, Triton X-100 has a slight activating effect on...

  9. Application of Chlorophyll Fluorescence Imaging Technology for Fresh Quality Control of Grape Fruit Preserved Under Different Storage Conditions

    OpenAIRE

    Sung Yung Yoo; Sok Samait; Jong Yong Park; Tae Wan Kim

    2014-01-01

    The objective of this study was to find a rapid determination of the freshness of grape (Vitis vinifera. L.) fruits using portable chlorophyll fluorescence imaging instrument. To assess the fresh quality of grape fruits, an imaging technique of the photochemical responses of pericarp of grape fruit was performed with fruits preserved under the different storage conditions. The observed chlorophyll imaging photos were numerically transformed to the photochemical parameters on the basis of chlo...

  10. A Label-Free Microfluidic Biosensor for Activity Detection of Single Microalgae Cells Based on Chlorophyll Fluorescence

    OpenAIRE

    Junsheng Wang; Jinyang Sun; Yongxin Song; Yongyi Xu; Xinxiang Pan; Yeqing Sun; Dongqing Li

    2013-01-01

    Detection of living microalgae cells is very important for ballast water treatment and analysis. Chlorophyll fluorescence is an indicator of photosynthetic activity and hence the living status of plant cells. In this paper, we developed a novel microfluidic biosensor system that can quickly and accurately detect the viability of single microalgae cells based on chlorophyll fluorescence. The system is composed of a laser diode as an excitation light source, a photodiode detector, a signal anal...

  11. Seaglider observations of variability in daytime fluorescence quenching of chlorophyll-a in Northeastern Pacific coastal waters

    OpenAIRE

    B. S. Sackmann; M.J. Perry; C. C. Eriksen

    2008-01-01

    The use of new autonomous and Lagrangian platforms (e.g. gliders, drifters, etc.) has revolutionized sampling of the ocean. The incorporation of in vivo chlorophyll-a fluorometers into these platforms for characterizing chlorophyll-a concentrations and phytoplankton biomass has reinforced the need for a thorough understanding of the variability and biases associated with basic fluorescence measurements. Seaglider, a long-range autonomous glider, has been deployed routinely i...

  12. Using leaf chlorophyll to parameterize light-use-efficiency within a thermal-based carbon, water and energy exchange model

    OpenAIRE

    HOUBORG RASMUS; Anderson, Martha C.; Daughtry, C.S.T.; W. P. Kustas; Rodell, Matthew

    2011-01-01

    Chlorophylls absorb photosynthetically active radiation and thus function as vital pigments for photosynthesis, which makes leaf chlorophyll content (Cab) useful for monitoring vegetation productivity and an important indicator of the overall plant physiological condition. This study investigates the utility of integrating remotely sensed estimates of Cab into a thermal-based Two-Source Energy Balance (TSEB) model that estimates land-surface CO2 and energy fluxes using an analytic...

  13. Chlorophyll catabolism in senescing plant tissues: In vivo breakdown intermediates suggest different degradative pathways for Citrus fruit and parsley leaves

    OpenAIRE

    Amir-Shapira, Dekel; Goldschmidt, Eliezer E.; Altman, Arie

    1987-01-01

    High-pressure liquid chromatography was used to separate chlorophyll derivatives in acetone extracts from senescing Citrus fruit peel, autumnal Melia azedarach L. leaves, and dark-held detached parsley (Petroselinum sativum L.) leaves. Chlorophyllide a and another polar, dephytylated derivative accumulated in large amounts in senescing Citrus peel, particularly in fruit treated with ethylene. Ethylene also induced a 4-fold increase in the specific activity of Citrus chlorophyllase (chlorophyl...

  14. Chlorophyll content mapping of urban vegetation in the city of Valencia based on the hyperspectral NAOC index

    OpenAIRE

    Delegido, Jesús; Van Wittenberghe, Shari; Verrelst, Jochem; Ortiz, Violeta; Veroustraete, Frank; Valcke, Roland; Samson, Roeland; Rivera, Juan P.; Tenjo, Carolina; Moreno, José

    2014-01-01

    Spatially distributed chlorophyll content of urban vegetation provides an important indicator of a plant's health status, which might depend on the habitat quality of the specific urban environment. Recent advances in optical remote sensing led to improved methodologies to monitor vegetation properties. The hyperspectral index NAOC (Normalized Area Over reflectance Curve) is one of these new tools that can be used for mapping chlorophyll content. In this paper we present the work done to quan...

  15. Variation in Chlorophyll Content per Unit Leaf Area in Spring Wheat and Implications for Selection in Segregating Material

    OpenAIRE

    John Hamblin; Katia Stefanova; Tefera Tolera Angessa

    2014-01-01

    Reduced levels of leaf chlorophyll content per unit leaf area in crops may be of advantage in the search for higher yields. Possible reasons include better light distribution in the crop canopy and less photochemical damage to leaves absorbing more light energy than required for maximum photosynthesis. Reduced chlorophyll may also reduce the heat load at the top of canopy, reducing water requirements to cool leaves. Chloroplasts are nutrient rich and reducing their number may increase availab...

  16. Biomass, chlorophyll and nitrogen content of leaves of two chili pepper varieties (Capsicum annum) in different fertilization treatments

    OpenAIRE

    SUTARNO; SUHARJA

    2009-01-01

    Suharja, Sutarno. 2009. Biomass, chlorophyll and nitrogen content of leaves of two chili pepper varieties (Capsicum annum) in different fertilization treatments. Nusantara Bioscience 1: 9-16. This study aims to determine the influence of various fertilization treatments on biomass, chlorophyll and nitrogen content of leaves from two varieties of chili, Sakti (large chili) and Fantastic (curly chili). The study was conducted in the village of Gatak, Karangnongko sub-district, Klaten District, ...

  17. Kinetics and thermodynamics of {beta}-carotene and chlorophyll adsorption onto acid-activated bentonite from Xinjiang in xylene solution

    Energy Technology Data Exchange (ETDEWEB)

    Wu Zhansheng [School of Life Science and Technology, Beijing Institute of Technology, Beijing 100081 (China); School of Chemistry and Chemical Engineering, Shihezi University, Shihezi, Xinjiang 832003 (China); Li Chun, E-mail: lichun@bit.edu.cn [School of Life Science and Technology, Beijing Institute of Technology, Beijing 100081 (China); School of Chemistry and Chemical Engineering, Shihezi University, Shihezi, Xinjiang 832003 (China)

    2009-11-15

    The kinetics and thermodynamics of {beta}-carotene and chlorophyll adsorption from xylene solution onto acid-activated bentonite (AAB) within the temperature range 65-95 deg. C were investigated. Adsorption of {beta}-carotene was described well with the Langmuir isotherm, whereas chlorophyll adsorption was determined well with the Freundlich isotherm, and the experimental data on chlorophyll adsorption were also fitted by the Langmuir isotherm to a certain extent, as reflected by correlation coefficients (R{sup 2}) over 0.9865. In addition, the adsorption of {beta}-carotene and chlorophyll onto AAB are favorable. The pseudo-second-order model was found to explain the kinetics of adsorption of both pigments more effectively. Increase of temperature enhanced the adsorption rate and equilibrium adsorption capacity of {beta}-carotene and chlorophyll on AAB. The activation energy for the sorption of {beta}-carotene and chlorophyll on AAB was 19.808 kJ/mol and 16.475 kJ/mol, respectively. The thermodynamic parameters {Delta}H{sup {theta}}, {Delta}S{sup {theta}} and {Delta}G{sup {theta}}, computed from K{sub F} of the adsorption isotherm constant, were 21.766 kJ/mol, 92.244 J/K mol and -9.554 kJ/mol respectively for the adsorption of {beta}-carotene on AAB at 65 deg. C, and for adsorption of chlorophyll on AAB at 65 deg. C were 31.051 kJ/mol, 93.549 J/K mol and -0.729 kJ/mol, respectively. The adsorption of {beta}-carotene and chlorophyll in xylene solution on AAB was a spontaneous and endothermic process with increasing in the randomness at the solid-solution interface.

  18. A Passive Method for Detecting Vegetation Stress from Orbit: Chlorophyll Fluorescence Spectra from Fraunhofer Lines

    Science.gov (United States)

    Theisen, Arnold F.

    2000-01-01

    Solar-stimulated chlorophyll fluorescence measured with the Fraunhofer line depth method has correlated well with vegetation stress in previous studies. However, the instruments used in those studies were limited to a single solar absorption line (e.g. 656.3 nm), obviating the red/far-red ratio (R/FR) method. Optics and detector technology have reached the level whereby multiple, very narrow Fraunhofer lines are resolvable. Thirteen such lines span the visible spectrum in the red to far-red region where chlorophyll fluorescence occurs. Fluorescence intensities at the 13 Fraunhofer line wavelengths were used to model emission spectra. The source data were collected for summer and fall bean crops (Phaseolus vulgaris L.) subjected to various levels of nitrogen fertilization. The intensities were adjusted to account for Fraunhofer line depth and atmospheric transmittance. Multiple R/FR fluorescence ratios, calculated from the modeled fluorescence spectra, correlated strongly with leaf chlorophyll concentration and well with applied nitrogen. The ratio yielding the best correlation with chlorophyll utilized red fluorescence at the 694.5 nm Fraunhofer line and farred fluorescence at the 755.6 nm Fraunhofer line. Twenty R/FR ratios, each evaluated for the maximum differential between low and high (optimal) nitrogen treatments, ranked higher in some cases and lower in others, possibly related to the time of year the crops were grown and the stage of growth of the crops. Ratios with 728.9 nm and 738.9 nm in the denominator consistently ranked in the lowest and next lowest quartile, respectively. Ratios of the 656.3 nm Fraunhofer line and the 755.6 nm line consistently ranked highest for the summer crop. Ratios with 755.6 nm in the denominator ranked in the upper quartile for 10 out of 12 measurement dates. Differences in ratio ranking indicate that physiological conditions may be estimated using selected ratios of Fraunhofer lines within the context of R/FR analysis. A

  19. Studies on liposomes with Chlorophyll for monitoring the electromagnetic influence at molecular level

    International Nuclear Information System (INIS)

    The liposomes with Chlorophyll are excellent model membranes and could be successfully used to study the electromagnetic influence at molecular level. The strong visible absorption and fluorescence of Chlorophyll allow its use as sensor for the interactions at molecular level and as a fluorescence marker; it reflects certain aspects of the supramolecular structure of the lipid phase: fluidity, lipid and liposomes aggregation. The objective of our work was to evidence athermal effect of low level, pulsed microwave (MW) fields on liposomes and to evidence the possible mechanism of interaction at molecular level. Unilamellar liposomes were obtained from multilamellar vesicles by the hand-shaken method and sonication for 30 minutes. The multilamellar vesicles were prepared using Chla /lipid films with specific molar ratio (lipid/Chla 1/10 and 1/100) and different lipids (Dipalmitoyl phosphatidylcholine, Dimirystoyl Phosphatidylcholine and Dioleoyl Phosphatidylcholine-Sigma). The films were dispersed in buffer solutions of different pH (6.2 - 7.6). The Chlorophyll was freshly extracted from spinach leaves and separated by the chromatographic method. Portions of liposome suspension (0.6 ml) were inserted into Teflon cuvettes. The samples were irradiated in series, for periods of 5-30 minutes. The exposure system was: MW generator + adapted load (shortened rectangular waveguide) + Teflon cuvette filled with sample liquid. The effect of MW irradiation is not observable on multilamellar vesicles, but only on small unilamellar vesicles. The MW effect is athermal, verified by conventional heating in the same range of temperatures and results in enlarging the size of vesicles. The enlarging effect of MW is opposed to the effect of ultrasounds exposure. It is not clear if effects due to MW are proportional with exposure duration; it seems that this mostly depends on the type of lipid in vesicles. The UV and VIS spectra were recorded to observe the oxidation state of the

  20. New vegetation indices for remote measurement of chlorophylls based on leaf directional reflectance spectra.

    Science.gov (United States)

    Maccioni, A; Agati, G; Mazzinghi, P

    2001-08-15

    Directional reflectance (R) spectra from 380 to 780 nm for nadir illuminated leaves of four different plants (croton, Codiaeum variegatum; spotted eleagnus, Eleagnus pungens Maculata; Japanese pittosporum, Pittosporum tobira and Benjamin fig, Ficus benjamina Starlight) were acquired at a viewing angle of 30 degrees from the nadir direction. Chlorophyll-a and -b content of leaves covered a range of 1-60 and 0.5-21 microg/cm(2), respectively. In contrast with previous results from hemispherical reflectance measurements, directional reflectance data does not correlate well with chlorophyll concentration. This is mainly due to the external reflectance (R(E)) at the leaf epidermis, caused by the mismatch of the refractive index at the air-epidermis and epidermis-inner layer boundary. The external reflectance can be identified with the blue flat reflectance between 380 and 480 nm. The inner reflectance (R(I)), obtained by subtracting the external reflectance from the measured spectra, was found to be linearly related to the logarithm of the chlorophyll content. Good fitting of the log (Chl) versus R(I)(lambda) curves were obtained for R(I) in the green band (around 550 nm) and close to the inflection point in the red edge (around 700 nm). The coefficient of determination, r(2), of curve fitting improved (up to 0.97) when the normalised inner reflectance NR(I)(lambda)=R(I)(lambda)/R(I)(lambda(0)), with lambda(0)>or=750 nm, was used instead of the absolute reflectance. The best indices for Chl, Chl-a and Chl-b determination were R(I)(542)/R(I)(750), R(I)(706)/R(I)(750) and R(I)(556)/R(I)(750), respectively. However, since the content of Chl-a relative to Chl-b was almost constant for the plants investigated, the two last indices must be further validated on leaves with a high variability in the Chl-a:Chl-b ratio. The error in the determination of chlorophyll content was found to be of the order of 10%. This value was lower than those obtained by applying the vegetation

  1. Chlorophyll catabolism in senescing plant tissues: In vivo breakdown intermediates suggest different degradative pathways for Citrus fruit and parsley leaves.

    Science.gov (United States)

    Amir-Shapira, D; Goldschmidt, E E; Altman, A

    1987-04-01

    High-pressure liquid chromatography was used to separate chlorophyll derivatives in acetone extracts from senescing Citrus fruit peel, autumnal Melia azedarach L. leaves, and dark-held detached parsley (Petroselinum sativum L.) leaves. Chlorophyllide a and another polar, dephytylated derivative accumulated in large amounts in senescing Citrus peel, particularly in fruit treated with ethylene. Ethylene also induced a 4-fold increase in the specific activity of Citrus chlorophyllase (chlorophyll chlorophyllidohydrolase, EC 3.1.1.14). Detailed kinetics based on a hexane/acetone solvent partition system showed that the in vivo increase in dephytylated derivatives coincided with the decrease in total chlorophyll. Polar, dephytylated derivatives accumulated also in senescing Melia leaves. Senescing parsley leaves revealed a very different picture. The gradual disappearance of chlorophyll a was accompanied by an increase in pheophytin a and by the transient appearance of several phytylated derivatives. Only pheophytin a and an adjacent peak were left when all the chlorophyll a had disappeared. The pathways for breakdown of chlorophyll in the Citrus and parsley senescence systems are discussed. PMID:16593821

  2. Mutagenic effects of gamma rays and EMS on frequency and spectrum of chlorophyll mutations in urdbean (Vigna mungo (L.) Hepper)

    International Nuclear Information System (INIS)

    Chlorophyll mutations act as a significant index in the judgment of induced genetic variations in mutagen treated populations. Different types of chlorophyll mutation have been observed in various crop plants. In the current study, the effect of different concentrations (40 kR, 50 kR and 60 kR) of gamma rays, Ethyl Methane Sulphonate (50 mM, 60 mM and 70 mM) in single and combination dose/concentration on the frequency and spectrum of chlorophyll mutation and the effect of VBN 4 urdbean variety to such irradiation dose was observed. Results showed induction of broad spectrum of chlorophyll mutations which included albina, xantha, chlorina and viridis. Among these chlorina type was predominant in all the mutagenic treatments. The albina type of chlorophyll mutants occurred very rarely and was found only at 60 mM of EMS treatment and at 40 kR + 50 mM, 60 kR + 70 mM of combination treatments. Based on the chlorophyll mutation frequency, gamma rays were most effective followed by EMS and combination of treatments. (author)

  3. Discovery of a chlorophyll binding protein complex involved in the early steps of photosystem II assembly in Synechocystis.

    Science.gov (United States)

    Knoppová, Jana; Sobotka, Roman; Tichy, Martin; Yu, Jianfeng; Konik, Peter; Halada, Petr; Nixon, Peter J; Komenda, Josef

    2014-03-01

    Efficient assembly and repair of the oxygen-evolving photosystem II (PSII) complex is vital for maintaining photosynthetic activity in plants, algae, and cyanobacteria. How chlorophyll is delivered to PSII during assembly and how vulnerable assembly complexes are protected from photodamage are unknown. Here, we identify a chlorophyll and β-carotene binding protein complex in the cyanobacterium Synechocystis PCC 6803 important for formation of the D1/D2 reaction center assembly complex. It is composed of putative short-chain dehydrogenase/reductase Ycf39, encoded by the slr0399 gene, and two members of the high-light-inducible protein (Hlip) family, HliC and HliD, which are small membrane proteins related to the light-harvesting chlorophyll binding complexes found in plants. Perturbed chlorophyll recycling in a Ycf39-null mutant and copurification of chlorophyll synthase and unassembled D1 with the Ycf39-Hlip complex indicate a role in the delivery of chlorophyll to newly synthesized D1. Sequence similarities suggest the presence of a related complex in chloroplasts. PMID:24681620

  4. Coincident patterns of waste water suspended solids reduction, water transparency increase and chlorophyll decline in Narragansett Bay.

    Science.gov (United States)

    Borkman, David G; Smayda, Theodore J

    2016-06-15

    Dramatic changes occurred in Narragansett Bay during the 1980s: water clarity increased, while phytoplankton abundance and chlorophyll concentration decreased. We examine how changes in total suspended solids (TSS) loading from wastewater treatment plants may have influenced this decline in phytoplankton chlorophyll. TSS loading, light and phytoplankton observations were compiled and a light- and temperature-dependent Skeletonema-based phytoplankton growth model was applied to evaluate chlorophyll supported by TSS nitrogen during 1983-1995. TSS loading declined 75% from ~0.60×10(6)kgmonth(-1) to ~0.15×10(6)kgmonth(-1) during 1983-1995. Model results indicate that nitrogen reduction related to TSS reduction was minor and explained a small fraction (~15%) of the long-term chlorophyll decline. The decline in NBay TSS loading appears to have increased water clarity and in situ irradiance and contributed to the long-term chlorophyll decline by inducing a physiological response of a ~20% reduction in chlorophyll per cell. PMID:27087354

  5. Analysis of in vivo chlorophyll fluorescence spectra to monitor physiological state of tomato plants growing under zinc stress.

    Science.gov (United States)

    Cherif, Jaouhra; Derbel, Najoua; Nakkach, Mohamed; Bergmann, Hubertus von; Jemal, Fatma; Lakhdar, Zohra Ben

    2010-12-01

    The effects of zinc (Zn) on plant chlorophyll fluorescence were investigated in 10-day-old tomato (Solanum lycopersicum) seedlings subjected for 7 days to a series of zinc (10, 50, 100 and 150μM) applied via the nutrient solution. The chlorophyll fluorescence spectra of leaves were recorded in the spectral region 650-800nm using the spectroscopic technique of ultraviolet light emitting diode induced fluorescence spectroscopy (UV-LED IFS). These spectra have been used to analyze the effect of several doses of zinc on the photosynthetic activities of tomato plants. The fluorescence intensity ratios (FIR) at the two maxima (F(690)/F(735)) of control as well as treated tomato plants were calculated by evaluating curve-fitted parameters using a Gaussian spectral function. The variable chlorophyll fluorescence decrease ratio (R(Fd)) values were determined from the fluorescence induction kinetics curves recorded at 690nm and 735nm. In addition, Zn accumulation in plants, plant growth, photosynthetic pigments content and malondialdehyde level (MDA, an index of lipid peroxidation) were also estimated. The results indicated that the plants treated with 10μM of zinc exhibited better growth, however, higher concentrations of zinc were harmful for plants. Excess Zn induced a decrease in the R(Fd) values, which was associated with a strong decline of the total chlorophylls content and an increase of MDA level. The total chlorophylls content decline could also be followed via an increase of the chlorophyll fluorescence ratio F(690)/F(735). PMID:20829059

  6. From the chlorophyll a in the surface layer to its vertical profile: a Greenland Sea relationship for satellite applications

    Directory of Open Access Journals (Sweden)

    A. Cherkasheva

    2013-04-01

    Full Text Available Current estimates of global marine primary production range over a factor of two. Improving these estimates requires an accurate knowledge of the chlorophyll vertical profiles, since they are the basis for most primary production models. At high latitudes, the uncertainty in primary production estimates is larger than globally, because here phytoplankton absorption shows specific characteristics due to the low-light adaptation, and in situ data and ocean colour observations are scarce. To date, studies describing the typical chlorophyll profile based on the chlorophyll in the surface layer have not included the Arctic region, or, if it was included, the dependence of the profile shape on surface concentration was neglected. The goal of our study was to derive and describe the typical Greenland Sea chlorophyll profiles, categorized according to the chlorophyll concentration in the surface layer and further monthly resolved profiles. The Greenland Sea was chosen because it is known to be one of the most productive regions of the Arctic and is among the regions in the Arctic where most chlorophyll field data are available. Our database contained 1199 chlorophyll profiles from R/Vs Polarstern and Maria S. Merian cruises combined with data from the ARCSS-PP database (Arctic primary production in situ database for the years 1957–2010. The profiles were categorized according to their mean concentration in the surface layer, and then monthly median profiles within each category were calculated. The category with the surface layer chlorophyll (CHL exceeding 0.7 mg C m−3 showed values gradually decreasing from April to August. A similar seasonal pattern was observed when monthly profiles were averaged over all the surface CHL concentrations. The maxima of all chlorophyll profiles moved from the greater depths to the surface from spring to late summer respectively. The profiles with the smallest surface values always showed a subsurface chlorophyll

  7. Validation of OCM-2 sensor performance in retrieving chlorophyll and TSM along the southwest Bay of Bengal coast

    Indian Academy of Sciences (India)

    R Shanthi; D Poornima; S Raja; G Vijayabaskara Sethubathi; T Thangaradjou; T Balasubramanian; K N Babu; A K Shukla

    2013-04-01

    The Chlorophyll and Total Suspended Matter (TSM) data retrieved from Ocean Colour Monitor (OCM-2) onboard Oceansat-2 were tested for the accuracy using in-situ measurements made along the southwest Bay of Bengal coast during cruises and monthly samplings synchronized with satellite overpass from January 2010 to May 2011. The observed range of in-situ chlorophyll and TSM concentrations were 0.10–4.60 gl−1 and 12.70–34.56 mgl−1 respectively, while OCM-2 derived chlorophyll and TSM concentration ranged from 0.324 to 1.552 gl−1 and 3.537 to 32.11 mgl−1, respectively. The in-situ dataset was grouped into low (0.1-0.5 gl−1), moderate (0.51-1.0 gl−1) and high (< 1 gl−1) chlorophyll concentration and low (12.7–17.81 mgl−1), moderate (18.1–29.0 mgl−1) and high (< 30 mgl−1) TSM concentration for evaluating the performance of algorithms against different ranges of field measurements. The OCM-2 chlorophyll retrieval algorithm (OC4V4) showed a systematic and large overestimation of low chlorophyll values with 2 = 0.607, root mean square error (RMSE) = 0.33 gl−1 and mean normalized bias (MNB) = 1.57 and consistent underestimation of high chlorophyll values with 2 = 0.497, RMSE = 1.486 gl−1 and MNB = 0.52 especially at nearshore waters due to the interference of suspended matter and coloured dissolved organic matter. However, moderate range of chlorophyll values showed better performance of OC4V4 algorithm in chlorophyll retrieval with 2 = 0.676, RMSE = 0.254 gl−1 and MNB = 0.09 when compared to low and high chlorophyll values. The TSM algorithm (modified algorithm of Tassan 1994) showed large underestimation in TSM retrievals and this was proved by the statistical results which shown maximum 2 = 0.551 for low TSM values with less RMSE = 0.909 mgl−1 and MNB = 0.616 error compared to moderate and high TSM values. OCM-2 retrieved TSM values were not well correlated with in-situ TSM concentration and constantly underestimates four times

  8. The persistence of a chlorophyll spectral biosignature from Martian evaporite and spring analogues under Mars-like conditions

    Science.gov (United States)

    Stromberg, J. M.; Applin, D. M.; Cloutis, E. A.; Rice, M.; Berard, G.; Mann, P.

    2014-07-01

    Spring and evaporite deposits are considered two of the most promising environments for past habitability on Mars and preservation of biosignatures. Manitoba, Canada hosts the East German Creek (EGC) hypersaline spring complex, and the post impact evaporite gypsum beds of the Lake St. Martin (LSM) impact. The EGC complex has microbial mats, sediments, algae and biofabrics, while endolithic communities are ubiquitous in the LSM gypsum beds. These communities are spectrally detectable based largely on the presence of a chlorophyll absorption band at 670 nm however, the robustness of this feature under Martian surface conditions was unclear. Biological and biology-bearing samples from EGC and LSM were exposed to conditions similar to the surface of present day Mars (high UV flux, 100 mbar, anoxic, CO2 rich) for up to 44 days, and preservation of the 670 nm chlorophyll feature and chlorophyll red-edge was observed. A decrease in band depth of the 670 nm band ranging from ~16 to 80% resulted, with correlations seen in the degree of preservation and the spatial proximity of samples to the spring mound and mineral shielding effects. The spectra were deconvolved to Mars Exploration Rover (MER) Pancam and Mars Science Laboratory (MSL) Mastcam science filter bandpasses to investigate the detectability of the 670 nm feature and to compare with common mineral features. The red-edge and 670 nm feature associated with chlorophyll can be distinguished from the spectra of minerals with features below ~1000 nm, such as hematite and jarosite. However, distinguishing goethite from samples with the chlorophyll feature is more problematic, and quantitative interpretation using band depth data makes little distinction between iron oxyhydroxides and the 670 nm chlorophyll feature. The chlorophyll spectral feature is observable in both Pancam and Mastcam, and we propose that of the proposed EXOMARS Pancam filters, the PHYLL filter is best suited for its detection.

  9. Temperature and plant adaptation. I. Interaction of temperature and light in the synthesis of chlorophyll in corn.

    Science.gov (United States)

    McWilliam, J R; Naylor, A W

    1967-12-01

    The effect of temperature and light intensity have been studied in relation to the greening of etiolated corn (Zea mays cv. Pioneer 309-B) seedlings. Chlorophyll accumulation is rapid at high temperature (28 degrees ) under all conditions of light intensity. At low temperature (16 degrees ), and particularly in combination with high light intensity (3000-4500 ft-c), the accumulation of both chlorophyll and carotene is inhibited.Low pigment content at 16 degrees is not directly due to a block in the pigment synthesizing mechanism, but rather to the photodestruction of chlorophyll prior to its stabilization in the membrane structure of the chloroplast lamellae. The parallel reduction in carotene content at high light intensity is probably a contributing factor, because of its role in protecting chlorophyll from photodestruction. The greater severity of photo-oxidation of chlorophyll at low temperature in corn when compared with wheat, appears to be due to a slower rate of protochlorophyllide synthesis and subsequent esterification. Thus in corn at 16 degrees there is a prolongation of the photosensitive stage during chlorophyll synthesis. Photo-oxidation at 16 degrees has also been shown to be a function of the incident light energy, with the photosynthetic pigments acting as receptors for their own destruction.In comparison with the behavior of corn, wheat seedlings green rapidly at high light intensity at both 16 degrees and 28 degrees . This contrasting temperature response with respect to chlorophyll synthesis may underlie a fundamental difference in adaptation of these 2 species to growth in the temperate zones of the world. PMID:16656709

  10. Factors challenging our ability to detect long-term trends in ocean chlorophyll

    Directory of Open Access Journals (Sweden)

    C. Beaulieu

    2012-11-01

    Full Text Available Global climate change is expected to affect the ocean's biological productivity. The most comprehensive information available about the global distribution of contemporary ocean primary productivity is derived from satellite data. Large spatial patchiness and interannual to multidecadal variability in chlorophyll a concentration challenges efforts to distinguish a global, secular trend given satellite records which are limited in duration and continuity. The longest ocean color satellite record comes from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS, which failed in December 2010. The Moderate Resolution Imaging Spectroradiometer (MODIS ocean color sensors are beyond their originally planned operational lifetime. Successful retrieval of a quality signal from the current Visible Infrared Imager Radiometer Suite (VIIRS instrument, or successful launch of the Ocean Land Colour Instrument (OLCI in 2013 will hopefully extend the ocean color time series and increase the potential for detecting trends in ocean productivity in the future. Alternatively, a potential discontinuity in the time series of ocean chlorophyll a, introduced by a change of instrument without overlap and opportunity for cross-calibration, would make trend detection even more challenging. In this paper, we demonstrate that there are a few regions with statistically significant trends over the ten years of SeaWiFS data, but at a global scale the trend is not large enough to be distinguished from noise. We quantify the degree to which red noise (autocorrelation especially challenges trend detection in these observational time series. We further demonstrate how discontinuities in the time series at various points would affect our ability to detect trends in ocean chlorophyll a. We highlight the importance of maintaining continuous, climate-quality satellite data records for climate-change detection and attribution studies.

  11. Phytoplankton carbon biomass and specific growth rates determined with the labeled chlorophyll a technique

    International Nuclear Information System (INIS)

    The labeled chlorophyll a technique, based on the incorporation of H14CO-3 into chlorophyll a (chl a) gives accurate determinations of both phytoplankton carbon biomass (Csub(p)) and specific growth rate (μ). Csub(P) and μ, derived from the labeled chl a method, exhibited a diel periodicity and the mean μ over 24 h compared well with the dilution rate for an oceanic microflagellate in NH+sub(4-) limited continuous culture. The specific activity of carbon in Csub(P) (Rsup(*)sub(CP)) and in chl a (Rsup(*)sub(chl) sub(a)) were equal after only 2 h and remained the same through 24 h. This supports the main assumption of the technique that within a useful time scale, the specific activities are equal. Values of Csub(P) and phytoplankton POC measured with a CHN analyser were the same for the microflagellate in continuous culture. Estimates of phytoplankton carbon derived from several indirect methods were either greater than (methods based on measurement of adenosine triphosphate and microscopic examination of cell counts and volumes) or less than (methods based on measurement of particulate organic carbon and chlorophyll a concentrations) values determined with the labeled chl a technique. Time course 14C incubations indicate that both Csub(P) and μ exhibit diel variability through 24 h in the fluorescence maximum layer and overlying water column in the Southern California Bight. Phytoplankton populations in the fluorescence maximum layer grew with generation times of 2 to 3 d, while generation times in the water column above averaged less than 1 d. (orig.)

  12. Factors challenging our ability to detect long-term trends in ocean chlorophyll

    Directory of Open Access Journals (Sweden)

    C. Beaulieu

    2013-04-01

    Full Text Available Global climate change is expected to affect the ocean's biological productivity. The most comprehensive information available about the global distribution of contemporary ocean primary productivity is derived from satellite data. Large spatial patchiness and interannual to multidecadal variability in chlorophyll a concentration challenges efforts to distinguish a global, secular trend given satellite records which are limited in duration and continuity. The longest ocean color satellite record comes from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS, which failed in December 2010. The Moderate Resolution Imaging Spectroradiometer (MODIS ocean color sensors are beyond their originally planned operational lifetime. Successful retrieval of a quality signal from the current Visible Infrared Imager Radiometer Suite (VIIRS instrument, or successful launch of the Ocean and Land Colour Instrument (OLCI expected in 2014 will hopefully extend the ocean color time series and increase the potential for detecting trends in ocean productivity in the future. Alternatively, a potential discontinuity in the time series of ocean chlorophyll a, introduced by a change of instrument without overlap and opportunity for cross-calibration, would make trend detection even more challenging. In this paper, we demonstrate that there are a few regions with statistically significant trends over the ten years of SeaWiFS data, but at a global scale the trend is not large enough to be distinguished from noise. We quantify the degree to which red noise (autocorrelation especially challenges trend detection in these observational time series. We further demonstrate how discontinuities in the time series at various points would affect our ability to detect trends in ocean chlorophyll a. We highlight the importance of maintaining continuous, climate-quality satellite data records for climate-change detection and attribution studies.

  13. Relationship between leaf optical properties, chlorophyll fluorescence and pigment changes in senescing Acer saccharum leaves.

    Science.gov (United States)

    Junker, Laura Verena; Ensminger, Ingo

    2016-06-01

    The ability of plants to sequester carbon is highly variable over the course of the year and reflects seasonal variation in photosynthetic efficiency. This seasonal variation is most prominent during autumn, when leaves of deciduous tree species such as sugar maple (Acer saccharum Marsh.) undergo senescence, which is associated with downregulation of photosynthesis and a change of leaf color. The remote sensing of leaf color by spectral reflectance measurements and digital repeat images is increasingly used to improve models of growing season length and seasonal variation in carbon sequestration. Vegetation indices derived from spectral reflectance measurements and digital repeat images might not adequately reflect photosynthetic efficiency of red-senescing tree species during autumn due to the changes in foliar pigment content associated with autumn phenology. In this study, we aimed to assess how effectively several widely used vegetation indices capture autumn phenology and reflect the changes in physiology and photosynthetic pigments during autumn. Chlorophyll fluorescence and pigment content of green, yellow, orange and red leaves were measured to represent leaf senescence during autumn and used as a reference to validate and compare vegetation indices derived from leaf-level spectral reflectance measurements and color analysis of digital images. Vegetation indices varied in their suitability to track the decrease of photosynthetic efficiency and chlorophyll content despite increasing anthocyanin content. Commonly used spectral reflectance indices such as the normalized difference vegetation index and photochemical reflectance index showed major constraints arising from a limited representation of gradual decreases in chlorophyll content and an influence of high foliar anthocyanin levels. The excess green index and green-red vegetation index were more suitable to assess the process of senescence. Similarly, digital image analysis revealed that vegetation

  14. Chlorophyll Fluorescence as a Tool to Assess the Regeneration Potential of African Violet Leaf Explants

    Directory of Open Access Journals (Sweden)

    Norbert KEUTGEN

    2016-06-01

    Full Text Available Micropropagation of many ornamentals has enabled their efficient commercialisation and many problems have been solved by the elaboration of adequate culture protocols. Nevertheless, a non-destructive technique for monitoring the developmental progress of explants would be desirable. The present study focussed on the applicability of chlorophyll fluorescence in leaf explants of African violet (a Saintpaulia ionantha × confusa – hybrid explanted onto Murashige and Skoog basic medium. The explants that survived on the medium without additional phytohormones had the capacity to develop further into two different kinds of explants: light green explants, characterized by a non-regular size growth and stiffer appearance, and dark green explants capable of organogenesis. Compared to the source leaves of African violet plants, explants were characterized by reduced chlorophyll (Chl and carotenoid (Car contents as well as a tendency towards a higher Car/Chl ratio. The Chl a/b ratio decreased significantly in the light green explants. A reduction of maximum quantum efficiency of photosystem II (Fv/Fm accompanied by a high percentage (> 50% of thermal energy dissipation as a consequence of an elevated light intensity (800 µmol m-2 s-1 quanta indicated photoinhibition in the light green explants, whereas in the dark green explants the largest percentage (> 50% of the light energy was dissipated into the fraction of photon energy trapped by ‘closed’ photosystem II reaction centres. These results suggest that the capacity of organogenesis of leaf explants of African violet can be monitored using chlorophyll fluorescence, because it is related to modifications of the photosynthetic system.

  15. Study of water chlorophyl content in the Venice Lagoon through hyperspectral data

    Science.gov (United States)

    Garfagnoli, Francesca; Bizzaro, Beatrice; Moretti, Sandro

    2013-04-01

    In the framework of the HICO Project (http://hico.coas.oregonstate.edu/), a number of radiance and reflectance images of the Venice Lagoon were used to evaluate the possibility of performing quick and reliable mapping of water quality parameters. Sponsored by the Office of Naval Research, the Hyperspectral Imager for the Coastal Ocean (HICO™) is the first spaceborne imaging spectrometer specifically designed to sample the coastal areas, with 128 spectral bands, a 90 m spatial resolution, full spectral coverage (380 to 960 nm sampled at 5.7 nm) and a very high signal-to-noise ratio to resolve the complexity of the coastal ocean. Eutrophication is one of the major causes of water quality deterioration. The concentration of chlorophyll-a found in water can be used to trace the abundance of planktonic algae in rivers, lakes or lagoons. The Venice Lagoon, famous worldwide, represents one of the most fragile and vulnerable ecosystems, which is being constantly threatened by factors of stress, both human and natural, such as erosion, presence of urban and agricultural sources of pollution, stress from fishing, pollution produced by the industrial area of Porto Marghera and by the city of Venice itself, downwash of sediments from the hinterland and eutrophication. Traditional methods of water quality estimation are often time consuming and involve periodical sampling and plenty of laboratory analyses. In this study the possibility of using imaging spectroscopy to rapidly obtain raster-based maps of chlorophyll concentration by comparing the results obtained through five different literature bio-optical models, which permit the retrieval of mathematical relations between the water's spectral properties and physicochemical parameters; pH, dissolved oxygen, turbidity and chlorophyll concentration. Evaluation of performances is achieved by comparing the hyperspectral based maps with maps of kriged concentration values, provided by the Magistrato delle Acque di Venezia (http

  16. Multispectral In-situ Measurements of Organic Matter and Chlorophyll Fluorescence in Seawater: Documenting the Intrusion of the Mississippi River Plume in the West Florida Shelf

    Science.gov (United States)

    DelCastillo, Carlos E.; Coble, Paula G.; Conmy, Robyn N.; Mueller-Karger, Frank E.; Vanderbloomen, Lisa; Vargo, Gabriel A.

    2000-01-01

    We performed multispectral in-situ fluorescence measurement of colored dissolved organic matter and chlorophyll in surface water of the West Florida Shelf using West Labs Spectral absorption and Fluorescence Instrument (SAFIre). Continuous measurements underway allowed us to simultaneously map the dispersion of riverine organic material and chlorophyll on the shelf. By using two fluorescence emission ratios we were able to differentiate between riverine and marine CDOM. Our data also showed unusually high concentrations of CDOM offshore. These were attributed to an intrusion of the Mississippi River Plume. We performed limited comparisons between in-situ chlorophyll concentrations measured with SAFIre and chlorophyll values obtained from SeaWiFS satellite data using OC4 and MODIS algorithm. Our results show that, although both algorithms overestimated chlorophyll, MODIS performed better than OC4, particularly in areas with high CDOM concentrations. Analysis of the relationship between chlorophyll and CDOM concentrations within the study area showed regional variability causes by differences in river source.

  17. Estimation of Norway Spruce leaf chlorophyll content from chris/proba satellite image data

    Czech Academy of Sciences Publication Activity Database

    Lukeš, Petr; Malenovský, Z.; Kaplan, Věroslav; Hanuš, Jan; Homolová, L.

    Noordwijk: ESA communication, 2010 - (Lacoste-Francis, H.), s. 1-4 ISBN 978-92-9221-247-6. ISSN 1609-042X. [Hyperspectral worskhop 2010 from chris/proba to PRISMA and EnMAP and beyond. Frascati (IT), 17.03.2010-19.03.2010] R&D Projects: GA MŽP(CZ) SP/2D1/70/08 Institutional research plan: CEZ:AV0Z60870520 Keywords : Norway spruce * chlorophyll * chris/proba Subject RIV: EH - Ecology, Behaviour

  18. Contrast agent free detection of bowel perforation using chlorophyll derivatives from food plants

    Science.gov (United States)

    Han, Jung Hyun; Jo, Young Goun; Kim, Jung Chul; Lee, Jee-Bum; Kim, Yong-Chul; Kang, Hoonsoo; Hwang, In-Wook

    2016-01-01

    Chlorophylls occur abundantly in food plants and show bright emission bands at long-wavelength regions (∼675 and ∼720 nm) compared to the autofluorescence of animal organs and peritoneal fluids. The use of these emissions as biomarkers for monitoring bowel perforation with a modality that does not involve synthetic contrast agents seems promising. To validate this, we measured the fluorescence spectra of rat organs, human peritoneal and intestinal fluids, and human intestinal fluids diluted with physiological saline. The developed technique showed a high detection sensitivity (∼50 ppm) under irrigation for abdominal surgery, highlighting the potential of this tool in the surgical setting.

  19. Remote sensing of chlorophyll a fluorescence of vegetation canopies. 1. Near and far field measurement techniques

    International Nuclear Information System (INIS)

    This article presents instruments and techniques, used in several vegetation monitoring experiments. Simultaneous monitoring was performed with different approaches, including fluorescence lidar and passive remote sensing, leaf level reflectance, and laser fluorimetry, and compared with physiological measurements. Most of the instrumentation described was designed and built for this application. Experiments were carried out in the laboratory and in the field, to investigate the relationship between chlorophyll fluorescence spectra and plant ecophysiology. Remote sensing, spectroscopy, and ecophysiology data were then collected by an intensive research team, joining different experiences and working in national and international projects

  20. Validation of MODIS FLH and In Situ Chlorophyll a from Tampa Bay, Florida (USA)

    Science.gov (United States)

    Fischer, Andrew; MorenoMadrinan, Max J.

    2012-01-01

    Satellite observation of phytoplankton concentration or chlorophyll-a (chla) is an important characteristic, critically integral to monitoring coastal water quality. However, the optical properties of estuarine and coastal waters are highly variable and complex and pose a great challenge for accurate analysis. Constituents such as suspended solids and dissolved organic matter and the overlapping and uncorrelated absorptions in the blue region of the spectrum renders the blue-green ratio algorithms for estimating chl-a inaccurate. Measurement of suninduced chlorophyll fluorescence, on the other hand, which utilizes the near infrared portion of the electromagnetic spectrum may, provide a better estimate of phytoplankton concentrations. While modelling and laboratory studies have illustrated both the utility and limitations of satellite algorithms based on the sun induced chlorophyll fluorescence signal, few have examined the empirical validity of these algorithms or compared their accuracy against bluegreen ratio algorithms . In an unprecedented analysis using a long term (2003-2011) in situ monitoring data set from Tampa Bay, Florida (USA), we assess the validity of the FLH product from the Moderate Resolution Imaging Spectrometer against a suite of water quality parameters taken in a variety of conditions throughout this large optically complex estuarine system. . Overall, the results show a 106% increase in the validity of chla concentration estimation using FLH over the standard chla estimate from the blue-green OC3M algorithm. Additionally, a systematic analysis of sampling sites throughout the bay is undertaken to understand how the FLH product responds to varying conditions in the estuary and correlations are conducted to see how the relationships between satellite FLH and in situ chlorophyll-a change with depth, distance from shore, from structures like bridges, and nutrient concentrations and turbidity. Such analysis illustrates that the correlations between

  1. Clearance rate of the mussel Mytilus galloprovincialis. I. Response to extreme chlorophyll ranges

    OpenAIRE

    Filgueira, Ramón; Fernández-Reiriz, María José; Labarta, Uxío

    2009-01-01

    [EN] Clearance rate (CR) measurements in Mytilus galloprovincialis were determined over 16 experiments in which the mussels were exposed to diets characterized by variable chlorophyll content (0.28–104.88 μg Chla L–1) in order to: (1) establish the lower trigger level and the saturation reduction, (2) elucidate whether these thresholds were controlled by an on/off switch or by a progressive response, and (3) determine whether the experimental time exerted an effect on the CR measurem...

  2. Rapid TaqMan-Based Quantification of Chlorophyll d-Containing Cyanobacteria in the Genus Acaryochloris

    DEFF Research Database (Denmark)

    Behrendt, Lars; Nielsen, Jeppe Lund; Sørensen, Søren;

    2014-01-01

    RNA gene copy numbers based on standard curves consisting of plasmid inserts. DNA from five Acaryochloris strains, i.e., MBIC11017, CCMEE5410, HICR111A, CRS, and Awaji-1, exhibited amplification efficiencies of>94% when tested in the TaqMan assay. When used on complex natural communities, the TaqMan assay......Reports of the chlorophyll (Chl) d-containing cyanobacterium Acaryochloris have accumulated since its initial discovery in 1996. The majority of this evidence is based on amplification of the gene coding for the 16S rRNA, and due to the wide geographical distribution of these sequences, a global...

  3. Chlorophyll content, productivities and biomass allocations of seagrasses in Talim Bay, Lian, Batangas, Philippines

    Directory of Open Access Journals (Sweden)

    Michael A. Clores

    2013-09-01

    Full Text Available This study determined the chlorophyll content, productivities and biomass allocations of three abundant species of seagrasses in Talim Bay, Lian, Batangas. Philippines: Enhalus acoroides, Cymodocea rotundata, and Thalassia hemprichii. Four seagrass meadows in the bay were selected based on their terrestrial sources of nutrient loads. Results reveal that seagrasses at South Matuod (a site which receives nutrient load drained mostly from corn- and cane-fields, yields the highest GPP (Gross Primary Productivity, but R (Respiration is higher than GPP, and therefore NPP (Net Primary Productivity was negative. The same pattern of productivity values were observed in the other sites implying that seagrasses were not making enough oxygen for their life processes at the time of the study (October to November 2010. Although the NPP of seagrasses was negative in Talim Point, (a site which does not receive nutrient load from terrestrial area serving as the control site, they had the highest chlorophyll a and b content with the other sites. R in this site is the lowest despite its low GPP, suggesting a more efficient primary production. Seagrasses in Kayreyna (which receives nutrient load from primarily from sewerage as well as farmland, i.e., near one creek that drains houses had the highest total average Wet weight (WW, Dry Weight (DW and Ash-Free Dry Weight (AFDW while those seagrasses collected in South Matuod had the lowest biomass. The low biomass of seagrasses in Matuod could be related to their very low productivity and low chlorophyll content needed for such production. Kayreyna is characterized by seagrasses with second highest chlorophyll content after Talim point, and in terms of productivity, two of seagrass species in this site E. acoroides and T. hemprichii are among those with the lowest R. Evidently, seagrasses in Talim Point, Shields Marine Station (the site which receives primarily agriculture run-off, i.e., near a creek that drains mostly

  4. Synoptic-scale analysis of mechanisms driving surface chlorophyll dynamics in the North Atlantic

    DEFF Research Database (Denmark)

    Ferreira, Ana Sofia; Hatun, H.; Counillon, F.; Payne, Mark; Visser, Andre

    2015-01-01

    show that, in terms of bottom-up processes alone, there is a dominant physical mechanism, namely mixed-layer shoaling, that best predicts the interannual variation in the initial increase in surface chlorophyll across large sectors of the North Atlantic. We further show that different regions are...... governed by different physical phenomena and that wind-driven mixing is a common component, with either heat flux or light as triggers. We believe these findings to be relevant to the ongoing discussion on North Atlantic bloom onset....

  5. Meris imageries to investigate surface chlorophyll in the upper gulf of Thailand

    OpenAIRE

    BURANAPRATHEPRAT, Anukul; NIEMANN, K. Olaf; MATSUMURA, Satsuki; Yanagi, Tetsuo

    2009-01-01

    Medium Resolution Imaging Spectrometer Instrument (MERIS) Level 2 data were used to investigate the seasonal patterns of surface chlorophyll-a (chl-a) distribution related to eutrophic conditions in the upper Gulf of Thailand (UGoT). Initial overestimation of chl-a using MERIS Rrs was reduced when Rrs ratios were used. A local in-water algorithm, named Chula algorithm, was embedded into MERIS data due to higher accuracy in chl-a prediction, compared to standard MERIS chl-a products. Subsequen...

  6. Evaluation of Copper Oxide Nanoparticles Toxicity Using Chlorophyll a Fluorescence Imaging in Lemna gibba

    OpenAIRE

    François Perreault; Abdallah Oukarroum; Laura Pirastru; Louka Sirois; William Gerson Matias; Radovan Popovic

    2010-01-01

    Copper oxide nanoparticles (CuO NPs), used in antifouling paints of boats, are released in the environment and can induce toxicity to aquatic organisms. In this report, we used chlorophyll a fluorescence imaging to evaluate CuO NPs toxicity in Lemna gibba. This approach allowed to evaluate the differential effect of CuO NPs on photosynthesis of whole L. gibba plants. Exposure to 0.1 to 0.4 g/L CuO NPs during 48h induced strong inhibition of photosynthetic processes resulting in a decrease of ...

  7. High night temperature-induced accelerated maturation of rice panicles can be detected by chlorophyll fluorescence

    Czech Academy of Sciences Publication Activity Database

    Šebela, David; Quiňones, C.; Olejníčková, Julie; Jagadish, K. S. V.

    Brno: Global Change Research Centre, The Czech Academy of Sciences, v. v. i., 2015 - (Urban, O.; Šprtová, M.; Klem, K.), s. 134-137 ISBN 978-80-87902-10-3. [Global Change: A Complex Challenge /4th/. Brno (CZ), 23.03.2015-24.03.2015] R&D Projects: GA MŠk EE2.3.20.0246; GA MŠk(CZ) LO1415 Institutional support: RVO:67179843 Keywords : temperature * chlorophyll fluorescence Subject RIV: EH - Ecology, Behaviour

  8. [Effects of controlled-release fertilizer on chrysanthemum leaf chlorophyll fluorescence characteristics and ornamental quality].

    Science.gov (United States)

    Song, Xu-xu; Zheng, Cheng-shu; Sun, Xia; Ma, Hai-yan

    2011-07-01

    Taking cut flower chrysanthemum 'Baima' as test material, a pot experiment was conducted to study the effects of controlled-release fertilizer on the leaf chlorophyll fluorescence parameters, chlorophyll and nutrient contents, and ornamental quality of chrysanthemum. Under no fertilization, the maximal photochemical efficiency of PS II in dark (F(v)/F(m)), potential photochemical efficiency of PS II (F(v)/F(0)), and quantum yield of PS II electron transport (phi(PS II)) decreased significantly, compared with those under fertilization. With the application of conventional compound fertilizers CCFA (N:P:K=20:8:10) and CCFB (N:P:K= 14:14:14), the F(v)/F(m), F(v)/F(0) and phi(PS II) had a slight increase in early period (30-60 d) but a remarkable decrease in mid and later periods (75 - 120 d), compared with those under the application of controlled-release fertilizers CRFA (N:P:K = 20:8:10) and CRFB (N:P:K= 14:14:14). Under the application of CRFA, the F(v)/F(m), phi(PS II), and photochemical quenching (q(P)) had somewhat increase, as compared with the application of CRFB. The non-photochemical quenching (NPQ) under the application of CRFA and CRFB decreased significantly, compared with that under the application of CCFA and CCFB and the control. The chlorophyll content had a similar change trend with F(v)/F(m), F(v)/F(0), and phi(PS II). The leaf N, P, and K contents, flower stalk length and stalk diameter, flower diameter, and flower fresh and dry mass at harvest stage all increased under the application of CRFA and CRFB, compared with those under the application of CCFA and CCFB and the control, and the flower fresh and dry mass was significantly higher under the application of CRFA than of CRFB. This study showed that controlled-release fertilizer could improve the ornamental quality of chrysanthemum via improving the leaf chlorophyll content, photochemical transduction rate, and nutrient uptake, and CRFA had better effects than CRFB. PMID:22007449

  9. The influence of Phaeocystis globosa on microscale spatial patterns of chlorophyll a and bulk-phase seawater viscosity

    OpenAIRE

    Seuront, L.; Lacheze, C.; Doubell, M.J.; Seymour, J.R.; Van Dongen-Vogels, V.; Newton, K; Alderkamp, A.-C.; J. G. Mitchell

    2007-01-01

    A two-dimensional microscale (5 cm resolution) sampler was used over the course of a phytoplankton spring bloom dominated by Phaeocystis globosa to investigate the structural properties of chlorophyll a and seawater excess viscosity distributions. The microscale distribution patterns of chlorophyll a and excess viscosity were never uniform nor random. Instead they exhibited different types and levels of aggregated spatial patterns that were related to the dynamics of the bloom. The chlorophyl...

  10. On the influence of dissolved organic-matter on remote-sensing of chlorophyll in the straits of skagerrak and kattegat

    OpenAIRE

    Karabashev, Gs

    1992-01-01

    An experimental techniques to estimate the influence of dissolved organic matter (DOM) on remote sensing of chlorophyll in water has been developed, based on the relationship between fluorescence and absorption of light by a substance. The profiles of fluorescence, chlorophyll content in sea water and estimates of light attenuation in water samples were used in the paper. These data have permitted to calculate the regressions linking fluorescence and light absorption at 450 nm by chlorophyll ...

  11. Influence of foliar application of silicon on chlorophyll fluorescence, photosynthetic pigments, and growth in water-stressed wheat cultivars differing in drought tolerance

    OpenAIRE

    MAGHSOUDI, KOBRA; Emam, Yahya; Ashraf, Muhammad

    2015-01-01

    The influence of foliar application of silicon (Si) on chlorophyll contents, chlorophyll fluorescence, and growth of four wheat cultivars differing in drought tolerance (Sirvan and Chamran, as relatively drought tolerant, and Shiraz and Marvdasht, as drought sensitive) was examined under water deficit (100% and 40% F.C.) created in a greenhouse. The results showed that water deficit decreased shoot and root lengths, shoot dry weight, root dry weight, water utilization efficiency, chlorophyll ...

  12. Vertical distribution of chlorophyll a concentration and phytoplankton community composition from in situ fluorescence profiles: a first database for the global ocean

    OpenAIRE

    R. Sauzède; Lavigne, H.; Claustre, H.; J. Uitz; C. Schmechtig; F. D'Ortenzio; Guinet, C.; Pesant, S.

    2015-01-01

    In vivo chlorophyll a fluorescence is a proxy of chlorophyll a concentration, and is one of the most frequently measured biogeochemical properties in the ocean. Thousands of profiles are available from historical databases and the integration of fluorescence sensors to autonomous platforms has led to a significant increase of chlorophyll fluorescence profile acquisition. To our knowledge, this important source of environmental data has not yet been included in global analyse...

  13. Vertical distribution of chlorophyll a concentration and phytoplankton community composition from in situ fluorescence profiles: a first database for the global ocean

    OpenAIRE

    R. Sauzède; Lavigne, H.; Claustre, H.; J. Uitz; C. Schmechtig; F. D'Ortenzio; Guinet, C.; Pesant, S.

    2015-01-01

    In vivo chlorophyll a fluorescence is a proxy of chlorophyll a concentration, and is one of the most frequently measured biogeochemical properties in the ocean. Thousands of profiles are available from historical databases and the integration of fluorescence sensors to autonomous platforms led to a significant increase of chlorophyll fluorescence profile acquisition. To our knowledge, this important source of environmental data has not yet been included in global analyses. A total o...

  14. Thermal-based modeling of coupled carbon, water, and energy fluxes using nominal light use efficiencies constrained by leaf chlorophyll observations

    OpenAIRE

    Schull, M. A.; Anderson, M C; Houborg, R.; Gitelson, A.; Kustas, W.P.

    2015-01-01

    Recent studies have shown that estimates of leaf chlorophyll content (Chl), defined as the combined mass of chlorophyll a and chlorophyll b per unit leaf area, can be useful for constraining estimates of canopy light use efficiency (LUE). Canopy LUE describes the amount of carbon assimilated by a vegetative canopy for a given amount of absorbed photosynthetically active radiation (APAR) and is a key parameter for modeling land-surface carbon fluxes. A carbon-enabled version ...

  15. Thermal-based modeling of coupled carbon, water and energy fluxes using nominal light use efficiencies constrained by leaf chlorophyll observations

    OpenAIRE

    Schull, M. A.; Anderson, M C; Houborg, R.; Gitelson, A.; Kustas, W.P.

    2014-01-01

    Recent studies have shown that estimates of leaf chlorophyll content (Chl), defined as the combined mass of chlorophyll a and chlorophyll b per unit leaf area, can be useful for constraining estimates of canopy light-use-efficiency (LUE). Canopy LUE describes the amount of carbon assimilated by a vegetative canopy for a given amount of Absorbed Photosynthetically Active Radiation (APAR) and is a key parameter for modeling land-surface carb...

  16. Environmental factors associated with long-term changes in chlorophyll-a concentration in the Amazon floodplain

    Directory of Open Access Journals (Sweden)

    J. P. Ometto

    2011-04-01

    Full Text Available Long-term environmental time series of continuously collected data are fundamental to identify and classify pulses and determine their role in aquatic systems. This paper presents in situ daily mean chlorophyll-a concentration time series, key information for the current understanding of carbon fluxes in and out of the Amazonian floodplain system. This paper also investigates how seasonal fluctuations in water level affect the relationship between chlorophyll-a concentration and some of its controlling limnological (water level, water surface temperature, pH and turbidity and meteorological (wind intensity, relative humidity and short wave radiation variables provided by an automatic monitoring system (Integrated System for Environmental Monitoring-SIMA deployed at Curai Lake. The data are collected in preprogrammed time interval (1 h and are transmitted by satellite in quasi-real time for any user in a range of 2500 km from the acquisition point. We used Pearson correlation to determine the quantitative relationship between chlorophyll-a time series and others environmental parameters. Fourier power spectrum analyses were applied to identify periods of high variability in chlorophyll-a time series and wavelet power spectrum analyses helped to characterize their time-frequency structure. To further investigate the relationship between chlorophyll-a and the statistically significant variable highlighted by Pearson's correlation, the set of time series was submitted to cross wavelet analysis. The time series of chlorophyll-a shows two high peaks (47 μg L−1 and 53.30 μg L−1 of concentration during a year: first during the rising water and second during the low water level. A small peak was observed during the high water level (10 μg L−1. For the most part of rising, high and receding water level, the chlorophyll-a concentration is often low (from 2.20 μg L−1 to 9.10 μg L−1. chlorophyll-a concentration displays periodicities ranging

  17. Development of an eco-protocol for seaweed chlorophylls extraction and possible applications in dye sensitized solar cells

    Science.gov (United States)

    Armeli Minicante, S.; Ambrosi, E.; Back, M.; Barichello, J.; Cattaruzza, E.; Gonella, F.; Scantamburlo, E.; Trave, E.

    2016-07-01

    Seaweeds are a reserve of natural dyes (chlorophylls a, b and c), characterized by low cost and easy supply, without potential environmental load in terms of land subtraction, and also complying with the requirements of an efficient waste management policy. In particular, the brown seaweed Undaria pinnatifida is a species largely present in the Venice Lagoon area, and for it a removal strategy is actually mandatory. In this paper, we set-up an eco-protocol for the best extraction and preparation procedures of the pigment, with the aim of finding an easy and affordable method for chlorophyll c extraction, exploring at the same time the possibility of using these algae within local sustainable management integrated strategies, among which the possible use of chlorophylls as a dye source in dye sensitized solar cells (DSSCs) is investigated. Experimental results suggest that the developed protocols are useful to optimize the chlorophyll c extraction, as shown by optical absorption spectroscopy measurements. The DSSCs built with the chlorophyll extracted by the proposed eco-protocol exhibit solar energy conversion efficiencies are similar to those obtained following extraction protocols with larger environmental impacts.

  18. Effects of Different Nitrogen Forms on the Contents of Chlorophyll and Mineral Elements in Chinese chive Seedlings

    Directory of Open Access Journals (Sweden)

    Yongdong Sun

    2014-05-01

    Full Text Available Chinese chive is an important leafy vegetable, for which nitrogen is vital for growth, development and nutritional quality. In order to study the effects of improved hoagland nutrient solution with different nitrate (NO3- to ammonium (NH4+ ratios (25:75, 50:50, 75:25 and 100:0 on the contents of chlorophyll and mineral elements (Ca, Fe, Zn, Cu, Mn, Mg and K for three cultivars, Saisong, Pingjiu No.4 and Pingjiu No.8, under 14 mmol/L nitrogen. An experiment was conducted at experimental plots and lab of the school of horticulture and landscape architecture, henan institute of science and technology. The results showed that the chlorophyll a, chlorophyll b and total chlorophyll of the three cultivars were all reached a maximum value with NO3- and NH4+ ratio of 50:50. The eight mineral elements contents were higher for three cultivars at a NO3- and NH4+ ratios of 50:50 and 75:25. It could be concluded that the NO3- and NH4+ ratio of 50:50 effectively improved the chlorophyll contents and promoted accumulation of mineral elements in Chinese chive under hydroponic culture and was the optimal ratio.

  19. A light-harvesting siphonaxanthin-chlorophyll a/b-protein complex of marine green alga,Bryopsis corticulans

    Institute of Scientific and Technical Information of China (English)

    CHEN Hui; SHEN Shihua; HE Junfang; LENG Jing; LI Liangbi; KUANG Tingyun

    2004-01-01

    A light-harvesting chlorophyll a/b-protein complex (LHCP) was isolated directly from thylakoid membranes of marine green alga, Bryopsis corticulans, by two consecutive runs of liquid chromatography. The trimeric form of the light-harvesting complex has been obtained by sucrose gradient ultracentrifugation. The result of SDSPAGE shows that the light-harvesting complex is composed of at least five apoproteins in which a protein with apparent molecular weight of about 31 kD was never found in the major light-harvesting complex (LHC Ⅱ) from higher plants.The isolated Bryopsis corticulans light-harvesting complex contains a specific carotenoid, siphonaxanthin, as well as chlorophyll (Chl) a, Chl b, neoxanthin and violaxanthin. Siphonaxanthin which is present in the light-harvesting siphonaxanthin-chlorophyll a/b-protein complex of Bryopsis corticulans is responsible for enhanced absorption in the blue-green region (530 nm). Efficient energy transfer from both siphonaxanthin and Chl b to Chl a in Bryopsis corticulans LHCP, which has similar absorption and fluorescence emission spectra to those of the lutein-chlorophyll a/b-protein of higher plants, proved that molecular arrangement of the light-harvesting pigments was highly ordered in the Bryopsis corticulans LHCP. The siphonaxanthin-chlorophyll a/b-proteins allow enhanced absorption of blue-green light, the predominant light available in deep ocean waters or shaded subtidal marine habitats.

  20. Alterations in Chlorophyll a Fluorescence and Pigments Concentration in the Leaves of Cauliflower and Broccoli Transplants Subjected to Chilling

    Directory of Open Access Journals (Sweden)

    Renata WOJCIECHOWSKA

    2016-06-01

    Full Text Available Chlorophyll a fluorescence parameters and photosynthetic pigments content in leaves of broccoli (Brassica oleracea L. var. italica cv. ‘Monaco’ F1 and cauliflower (Brassica oleracea L. var. botrytis cv. ‘Bruce’ F1 transplants were analyzed to investigate the effects of chilling temperatures (6 and 10 °C and the exposure length (1 or 2 weeks on the photosynthetic apparatus condition in 3-year experiment. Data were compared to control plants exposed to 14 °C for 1 and 2 weeks. The lowest values of maximum quantum efficiency of photosystem II (Fv/Fm and the performance index (PI were observed in cauliflower chilled at 6 °C for 2 weeks. This was not accompanied by any substantial reduction in chlorophylls concentration, however, significant correlations between Fv/Fm or PI and chlorophylls content in cauliflower leaves were found. There was no negative effects of chilling on photosynthetic activity and chlorophyll content in broccoli leaves, the amount of carotenoids significantly increased in the broccoli chilled for 2 weeks in 6 °C. The chlorophyll a fluorescence indices and accelerated carotenoids synthesis showed that broccoli had less vulnerable photosynthetic apparatus to stress-induced temperatures and more efficient protection mechanisms in comparison to cauliflower transplants.

  1. Prediction of chlorophyll-a concentration by HJ-1 satellite imagery for Xiangxi Bay in Three Gorges Reservoir

    Directory of Open Access Journals (Sweden)

    Dong-xing FAN

    2014-01-01

    Full Text Available Since the impoundment of the Three Gorges Reservoir in 2003, algal blooms have frequently been observed in it. The chlorophyll a concentration is an important parameter for evaluating algal blooms. In this study, the chlorophyll a concentration in Xiangxi Bay, in the Three Gorges Reservoir, was predicted using HJ-1 satellite imagery. Several models were established based on a correlation analysis between in situ measurements of the chlorophyll a concentration and the values obtained from satellite images of the study area from January 2010 to December 2011. Chlorophyll a concentrations in Xiangxi Bay were predicted based on the established models. The results show that the maximum correlation is between the reflectance of the band combination of B4/(B2+B3 and in situ measurements of chlorophyll a concentration. The root mean square errors of the predicted values using the linear and quadratic models are 18.49 mg/m3 and 18.52 mg/m3, respectively, and the average relative errors are 37.79% and 36.79%, respectively. The results provide a reference for water bloom prediction in typical tributaries of the Three Gorges Reservoir and contribute to large-scale remote sensing monitoring and water quality management.

  2. Change Law of Hyperspectral Data in Related with Chlorophyll and Carotenoid in Rice at Different Developmental Stages

    Institute of Scientific and Technical Information of China (English)

    DENG Zhi-rui; TANG Yan-lin; ZHANG Rong-xian; HUANG Jing-feng; WANG Ren-chao

    2004-01-01

    The hyperspectral reflectances of the canopy, the first and the third unfolding leaves from the top and the panicles of two rice varieties (Xiushui 110 and Xieyou 9308) were measured by a ASD FieldSpec Pro FRTM in field and indoor environments under three nitrogen levels at different developmental stages. The concentrations of chlorophyll and carotenoid in leaves and panicle corresponding to the spectra were determined by biochemical method. The spectral differences were significant for rice under different nitrogen levels, and the concentrations of chlorophyll and carotenoid in leaves increased along with increasing applied nitrogen. There were more pronounced differences for the pigment concentrations in rice leaves with different nitrogen levels. The spectral reflectance of canopy was gradually getting smaller in the visible region and bigger in the near infrared region as the growth edge in the spectra of canopy, leaves and panicle after heading. The concentrations of chlorophyll and carotenoid in leaves presented S-shape change. The concentrations of chlorophyll and carotenoid in canopies, leaves and panicles were highly significantly correlated to the hyperspectral vegetation indices (Vis) R990/R553, R1200/R553, R750/R553, R553/R670, R800/R553, PSSRa,PSNDa and the red edge position λ red, indicating that these Vis could be used to estimate the concentrations of chlorophyll and carotenoid in canopies, leaves and panicles of rice.

  3. Changes in Chlorophyll Fluorescence of Rice Mutants Induced by High Hydrostatic Pressure

    Institute of Scientific and Technical Information of China (English)

    BAI; Cheng-ke; LI; Gui-shuang; PENG; Chang-lian; DUAN; Jun

    2003-01-01

    Three mutants of rice (Oryza sativa L. ), Mutant 1, Mutant 2and Mutant 3, which were selected by high hydrostatic pressure (75 MPa), and their parent Yuexiangzhan were used to study the changes in chlorophyll fluorescence during different growth stages. In all the three mutants, the function of PSⅡ was improved, Fy/Fm ratio of mutants increased compared to their parent at tillering and heading stage, and φPS Ⅱ also improved except for Mutant 2 at heading stage. Similar to their parent, the mutants exhibited slight photoinhibition at noon and almost complete recovery to initial levels of 6:00 after 18:00 at heading stage. At milking stage, the photoinhibition in the mutants was obvious, and recovered rapidly compared to the parent. Yields of individual plant and grain/straw ratio were also higher in three mutants than the parent. Results indicated that characteristics of chlorophyll fluorescence in leaves of mutants and their photoinhibition in the field had changed. It is suggested that high hydrostatic pressure induction could be applied as a new effective approach in high-yield rice breeding in the future.

  4. Evaluation of empirical and semi-analytical chlorophyll algorithms in the Ligurian and North Tyrrhenian Seas

    Science.gov (United States)

    Lapucci, Chiara; Ampolo Rella, Marina; Brandini, Carlo; Ganzin, Nicolas; Gozzini, Bernardo; Maselli, Fabio; Massi, Luca; Nuccio, Caterina; Ortolani, Alberto; Trees, Charles

    2012-01-01

    The estimation of chlorophyll concentration in marine waters is fundamental for a number of scientific and practical purposes. Standard ocean color algorithms applicable to moderate resolution imaging spectroradiometer (MODIS) imagery, such as OC3M and MedOC3, are known to overestimate chlorophyll concentration ([CHL]) in Mediterranean oligotrophic waters. The performances of these algorithms are currently evaluated together with two relatively new algorithms, OC5 and SAM_LT, which make use of more of the spectral information of MODIS data. This evaluation exercise has been carried out using in situ data collected in the North Tyrrhenian and Ligurian Seas during three recent oceanographic campaigns. The four algorithms perform differently in Case 1 and Case 2 waters defined following global and local classification criteria. In particular, the mentioned [CHL] overestimation of OC3M and MedOC3 is not evident for typical Case 1 waters; this overestimation is instead significant in intermediate and Case 2 waters. OC5 and SAM_LT are less sensitive to this problem, and are generally more accurate in Case 2 waters. These results are finally interpreted and discussed in light of a possible operational utilization of the [CHL] estimation methods.

  5. The Use of Chlorophyll Fluorescence Lifetime to Assess Phytoplankton Physiology within a River-Dominated Environment

    Science.gov (United States)

    Hall, Callie M.; Miller, Richard L.; Redalje, Donald G.; Fernandez, Salvador M.

    2002-01-01

    Chlorophyll a fluorescence lifetime was measured for phytoplankton populations inhabiting the three physical zones surrounding the Mississippi River's terminus in the Gulf of Mexico. Observations of river discharge volume, nitrate + nitrite, silicate, phosphate, PAR (Photosynthetically Active Radiation) diffuse attenuation within the water column, salinity, temperature, SPM, and chl a concentration were used to characterize the distribution of chl fluorescence lifetime within a given region within restricted periods of time. 33 stations extending from the Mississippi River plume to the shelf break of the Louisiana coast were surveyed for analysis of chlorophyll fluorescence lifetime during two cruises conducted March 31 - April 6, 2000, and October 24 - November 1, 2000. At each station, two to three depths were chosen for fluorescence lifetime measurement to represent the vertical characteristics of the water column. Where possible, samples were taken from just below the surface and from just above and below the pycnocline. All samples collected were within the 1% light level of the water column (the euphotic zone). Upon collection, samples were transferred to amber Nalgene bottles and left in the dark for at least 15 minutes to reduce the effects of non-photochemical quenching and to insure that photosynthetic reaction centers were open. Before measurements within the phase fluorometer were begun, the instrument was allowed to warm up for no less than one hour.

  6. Development of a canopy Solar-induced chlorophyll fluorescence measurement instrument

    International Nuclear Information System (INIS)

    A portable solar-induced chlorophyll fluorescence detecting instrument based on Fraunhofer line principle was designed and tested. The instrument has a valid survey area of 1.3 × 1.3 meter when the height was fixed to 1.3 meter. The instrument uses sunlight as its light source. The instrument is quipped with two sets of special photoelectrical detectors with the centre wavelength at 760 nm and 771 nm respectively and bandwidth less than 1nm. Both sets of detectors are composed of an upper detector which are used for detecting incidence sunlight and a bottom detector which are used for detecting reflex light from the canopy of crop. This instrument includes photoelectric detector module, signal process module, A/D convert module, the data storage and upload module and human-machine interface module. The microprocessor calculates solar-induced fluorescence value based on the A/D values get from detectors. And the value can be displayed on the instrument's LCD, stored in the flash memory of instrument and can also be uploaded to PC through the PC's serial interface. The prototype was tested in the crop field and the results demonstrate that the instrument can measure the solar-induced chlorophyll value exactly with the correlation coefficients was 0.9 compared to the values got from Analytical Spectral Devices FieldSpec Pro spectrometer. This instrument can diagnose the plant growth status by the acquired spectral response

  7. Toxicological effects of chlorpyrifos on growth, enzyme activity and chlorophyll a synthesis of freshwater microalgae.

    Science.gov (United States)

    Chen, Shangchao; Chen, Mindong; Wang, Zhuang; Qiu, Weijian; Wang, Junfeng; Shen, Yafei; Wang, Yajun; Ge, Shun

    2016-07-01

    This paper aims to acquire the experimental data on the eco-toxicological effects of agricultural pollutants on the aquatic plants and the data can support the assessment of toxicity on the phytoplankton. The pesticide of Chlorpyrifos used as a good model to investigate its eco-toxicological effect on the different microalgae in freshwater. In order to address the pollutants derived from forestry and agricultural applications, freshwater microalgae were considered as a good sample to investigate the impact of pesticides such as Chlorpyrifos on aquatic life species. Two microalgae of Chlorella pyrenoidosa and Merismopedia sp. were employed to evaluate toxicity of Chlorpyrifos in short time and long time by means of measuring the growth inhibition rate, the redox system and the content of chlorophyll a, respectively. In this study, the results showed that EC50 values ranging from 7.63 to 19.64mg/L, indicating the Chlorpyrifos had a relatively limited to the growth of algae during the period of the acute toxicity experiment. Moreover, when two kinds of algae were exposed to a medium level of Chlorpyrifos, SOD and CAT activities were importantly advanced. Therefore, the growth rate and SOD and CAT activities can be highly recommended for the eco-toxicological assessment. In addition, chlorophyll a also could be used as a targeted parameter for assessing the eco-toxicity of Chlorpyrifos on both Chlorella pyrenoidosa and Merismopedia sp. PMID:27314761

  8. Effect of arsenic on reflectance spectra and chlorophyll fluorescence of aquatic plants.

    Science.gov (United States)

    Iriel, Analia; Dundas, Gavin; Fernández Cirelli, Alicia; Lagorio, Maria G

    2015-01-01

    Arsenic pollution of groundwater is a serious problem in many regions of Latin America that causes severe risks to human health. As a consequence, non-destructive monitoring methodologies, sensitive to arsenic presence in the environment and able to perform a rapid screening of large polluted areas, are highly sought-after. Both chlorophyll - a fluorescence and reflectance of aquatic plants may be potential indicators to sense toxicity in water media. In this work, the effects of arsenic on the optical and photophysical properties of leaves of different aquatic plants (Vallisneria gigantea, Azolla filiculoides and Lemna minor) were evaluated. Reflectance spectra were recorded for the plant leaves from 300 to 2400 nm. The spectral distribution of the fluorescence was also studied and corrected for light re-absorption processes. Photosynthetic parameters (Fv/Fm and ΦPSII) were additionally calculated from the variable chlorophyll fluorescence recorded with a pulse amplitude modulated fluorometer. Fluorescence and reflectance properties for V. gigantea and A. filiculoides were sensitive to arsenic presence in contrast to the behaviour of L. minor. Observed changes in fluorescence spectra could be interpreted in terms of preferential damage in photosystem II. The quantum efficiency of photosystem II for the first two species was also affected, decreasing upon arsenic treatment. As a result of this research, V. gigantea and A. filiculoides were proposed as bioindicators of arsenic occurrence in aquatic media. PMID:25150973

  9. Chlorophyll degradation in the gut of generalist and specialist Lepidopteran caterpillars.

    Science.gov (United States)

    Badgaa, Amarsanaa; Jia, Aiqun; Ploss, Kerstin; Boland, Wilhelm

    2014-12-01

    Plant feeding herbivores excrete most of the ingested chlorophyll (Chl) as partly degraded derivatives lacking the phytol side chain and the central magnesium ion. An ecological role of digested and degraded Chls in the interactions between insects, their food plant and other insects has been described recently. To gain more information on common degradation patterns in plant-feeding insects, the orals secretions and frass of five Lepidopteran caterpillars covering generalists and specialists, namely Spodoptera littoralis, Spodoptera eridania, Heliothis virescens, Helicoverpa armigera, Manduca sexta, and, for comparison, of the leaf beetle larva Chrysomela lapponica were analyzed for chlorophyll catabolites. The major degradation products were determined as pheohorbide a/b and pyropheophorbide a/b by using LC-MS, LC-NMR, UV, and fluorescence spectrometry. The compounds were not present in fresh leaves of the food plants (Phaseolus lunatus, Nicotiana tabacum). The catabolite spectrum in generalists and specialists was qualitatively similar and could be attributed to the action of gut proteins and the strongly alkaline milieu in the digestive tract. Due to the anaerobic environment of the larval gut, the tetrapyrrole core of the Chl catabolites was not cleaved. Substantial amounts of Chl a/b metabolites were strongly complexed by a protein in the mid-gut. PMID:25416033

  10. Analysis of MERIS Reflectance Algorithms for Estimating Chlorophyll-a Concentration in a Brazilian Reservoir

    Directory of Open Access Journals (Sweden)

    Pétala B. Augusto-Silva

    2014-11-01

    Full Text Available Chlorophyll-a (chl-a is a central water quality parameter that has been estimated through remote sensing bio-optical models. This work evaluated the performance of three well established reflectance based bio-optical algorithms to retrieve chl-a from in situ hyperspectral remote sensing reflectance datasets collected during three field campaigns in the Funil reservoir (Rio de Janeiro, Brazil. A Monte Carlo simulation was applied for all the algorithms to achieve the best calibration. The Normalized Difference Chlorophyll Index (NDCI got the lowest error (17.85%. The in situ hyperspectral dataset was used to simulate the Ocean Land Color Instrument (OLCI spectral bands by applying its spectral response function. Therefore, we evaluated its applicability to monitor water quality in tropical turbid inland waters using algorithms developed for MEdium Resolution Imaging Spectrometer (MERIS data. The application of OLCI simulated spectral bands to the algorithms generated results similar to the in situ hyperspectral: an error of 17.64% was found for NDCI. Thus, OLCI data will be suitable for inland water quality monitoring using MERIS reflectance based bio-optical algorithms.

  11. Prospects for Detecting Oxygen, Water, and Chlorophyll in an Exo-Earth

    CERN Document Server

    Brandt, Timothy D

    2014-01-01

    The goal of finding and characterizing nearby Earth-like planets is driving many NASA high-contrast flagship mission concepts, the latest of which is known as the Advanced Technology Large-Aperture Space Telescope (ATLAST). In this article, we calculate the optimal spectral resolution $R=\\lambda/\\delta\\lambda$ and minimum signal-to-noise ratio per spectral bin (SNR), two central design requirements for a high-contrast space mission, in order to detect signatures of water, oxygen, and chlorophyll on an Earth twin. We first develop a minimally parametric model and demonstrate its ability to fit model Earth spectra; this allows us to measure the statistical evidence for each component's presence. We find that water is the most straightforward to detect, requiring a resolving power R>~20, while the optimal resolving power for oxygen is likely to be closer to R=150, somewhat higher than the canonical value in the literature. At these resolutions, detecting oxygen will require ~3 times the SNR as water. Chlorophyll...

  12. Effect of Chlorocholine Chloride on Chlorophyll, Photosynthesis, Soluble Sugar and Flavonoids of Ginkgo biloba

    Directory of Open Access Journals (Sweden)

    Weiwei ZHANG

    2013-05-01

    Full Text Available The flavonoids content determines the quality characteristics of Ginkgo biloba extract that could be increased by using of plant growth regulators. The objective of study was to investigate the effect of chlorocholine chloride (CCC, an anti-gibberellin growth retardant, on photosynthesis, chlorophyll, soluble sugar, total amino acids and phenylalanine contents, flavonoid accumulation, and flavonoids enzyme activity in G. biloba leaves. The ginkgo seedlings were grown in the greenhouse conditions with foliar applications of 0 (control, 0.5, 1.0 and 2.0 g l-1 CCC. Results showed that 0.5, 1.0 and 2.0 g l-1 CCC treatments significantly increased photosynthetic rates of leaves, the contents of chlorophyll, soluble sugar, total amino acids and phenylalnine in ginkgo leaves. Total polyphenols, flavonoids, anthocyanins content, phenylalanine ammonia-lyase (PAL, chalcone synthase (CHS and chalcone isomerase (CHI activities were all significantly increased by 1.0 and 2.0 g l-1 CCC treatments. Foliar treatment with CCC therefore might be a useful means of improving pharmacological properties of G. biloba leaves.

  13. Triplet excited state energies and phosphorescence spectra of (bacterio)chlorophylls.

    Science.gov (United States)

    Hartzler, Daniel A; Niedzwiedzki, Dariusz M; Bryant, Donald A; Blankenship, Robert E; Pushkar, Yulia; Savikhin, Sergei

    2014-07-01

    (Bacterio)Chlorophyll ((B)Chl) molecules play a major role in photosynthetic light-harvesting proteins, and the knowledge of their triplet state energies is essential to understand the mechanisms of photodamage and photoprotection, as the triplet excitation energy of (B)Chl molecules can readily generate highly reactive singlet oxygen. The triplet state energies of 10 natural chlorophyll (Chl a, b, c2, d) and bacteriochlorophyll (BChl a, b, c, d, e, g) molecules and one bacteriopheophytin (BPheo g) have been directly determined via their phosphorescence spectra. Phosphorescence of four molecules (Chl c2, BChl e and g, BPheo g) was characterized for the first time. Additionally, the relative phosphorescence to fluorescence quantum yield for each molecule was determined. The measurements were performed at 77K using solvents providing a six-coordinate environment of the Mg(2+) ion, which allows direct comparison of these (B)Chls. Density functional calculations of the triplet state energies show good correlation with the experimentally determined energies. The correlation determined computationally was used to predict the triplet energies of three additional (B)Chl molecules: Chl c1, Chl f, and BChl f. PMID:24896677

  14. Web camera as low cost multispectral sensor for quantification of chlorophyll in soybean leaves

    Science.gov (United States)

    Adhiwibawa, Marcelinus A.; Setiawan, Yonathan E.; Prilianti, Kestrilia R.; Brotosudarmo, Tatas H. P.

    2015-01-01

    Soybeans is one of main crops in Indonesia but the demand for soybeans is not followed by an increase in soybeans national production. One of the production limitation factor is the availability of lush cultivation area for soybeans plantation. Indonesian farners are usually grow soybeans in marginal cultivation area that requires soybeans varieties which tolerant with environmental stress such as drought, nutrition limitation, pest, disease and many others. Chlorophyll content in leaf is one of plant health indicator that can be used to determine environmental stress tolerant soybean varieties. However, there are difficulties in soybeans breeding research due to the manual acquisition of data that are time consume and labour extensive. In this paper authors proposed automatic system of soybeans leaves area and chlorophyll quantification based on low cost multispectral sensor using web camera as an indicator of soybean plant tollerance to environmental stress particularlly drought stress. The system acquires the image of the plant that is placed in the acquisition box from the top of the plant. The image is segmented using NDVI (Normalized Difference Vegetation Index) from image and quantified to yield an average value of NDVI and leaf area. The proposed system showed that acquired NDVI value has a strong relationship with SPAD value with r-square value 0.70, while the leaf area prediction has error of 18.41%. Thus the automation system can quantify plant data with good result.

  15. Assessment of remotely sensed chlorophyll-a concentration in Guanabara Bay, Brazil

    Science.gov (United States)

    Oliveira, Eduardo N.; Fernandes, Alexandre M.; Kampel, Milton; Cordeiro, Renato C.; Brandini, Nilva; Vinzon, Susana B.; Grassi, Renata M.; Pinto, Fernando N.; Fillipo, Alessandro M.; Paranhos, Rodolfo

    2016-04-01

    The Guanabara Bay (GB) is an estuarine system in the metropolitan region of Rio de Janeiro (Brazil), with a surface area of ˜346 km2 threatened by anthropogenic pressure. Remote sensing can provide frequent data for studies and monitoring of water quality parameters, such as chlorophyll-a concentration (Chl-a). Different combination of Medium Resolution Imaging Spectrometer (MERIS) remote sensing reflectance band ratios were used to estimate Chl-a. Standard algorithms such as Ocean Color 3-band, Ocean Color-4 band, fluorescence line height, and maximum chlorophyll index were also tested. The MERIS Chl-a estimates were statistically compared with a dataset of in situ Chl-a (2002 to 2012). Good correlations were obtained with the use of green, red, and near-infrared bands. The best performing algorithm was based on the red (665 nm) and green (560 nm) band ratio, named "RG3" algorithm (r2=0.71, chl-a=62,565*x1.6118). The RG3 was applied to a time series of MERIS images (2003- to 2012). The GB has a high temporal and spatial variability of Chl-a, with highest values found in the wet season (October to March) and in some of the most internal regions of the estuary. Lowest concentrations are found in the central circulation channel due to the flushing of ocean water masses promoted by pumping tide.

  16. Retrieval of aerosol parameters from the oxygen A band in the presence of chlorophyll fluorescence

    Directory of Open Access Journals (Sweden)

    A. F. J. Sanders

    2013-10-01

    Full Text Available We have investigated the precision of retrieved aerosol parameters for a generic aerosol retrieval algorithm over vegetated land using the O2 A band. Chlorophyll fluorescence is taken into account in the forward model. Fluorescence emissions are modeled as isotropic contributions to the upwelling radiance field at the surface and they are retrieved along with aerosol parameters. Precision is calculated by propagating measurement errors and a priori errors, including model parameter errors, using the forward model's derivatives. Measurement errors consist of noise and calibration errors. The model parameter errors considered are related to the single scattering albedo, surface pressure and temperature profile. We assume that measurement noise is dominated by shot noise; thus, results apply to grating spectrometers in particular. We describe precision for various atmospheric states, observation geometries and spectral resolutions of the instrument in a number of retrieval simulations. These precision levels can be compared with user requirements. A comparison of precision estimates with the literature and an analysis of the dependence on the a priori error in the fluorescence emission indicate that aerosol parameters can be retrieved in the presence of chlorophyll fluorescence: if fluorescence is present, fluorescence emissions should be included in the state vector to avoid biases in retrieved aerosol parameters.

  17. Retrieval of aerosol parameters from the oxygen A band in the presence of chlorophyll fluorescence

    Science.gov (United States)

    Sanders, A. F. J.; de Haan, J. F.

    2013-10-01

    We have investigated the precision of retrieved aerosol parameters for a generic aerosol retrieval algorithm over vegetated land using the O2 A band. Chlorophyll fluorescence is taken into account in the forward model. Fluorescence emissions are modeled as isotropic contributions to the upwelling radiance field at the surface and they are retrieved along with aerosol parameters. Precision is calculated by propagating measurement errors and a priori errors, including model parameter errors, using the forward model's derivatives. Measurement errors consist of noise and calibration errors. The model parameter errors considered are related to the single scattering albedo, surface pressure and temperature profile. We assume that measurement noise is dominated by shot noise; thus, results apply to grating spectrometers in particular. We describe precision for various atmospheric states, observation geometries and spectral resolutions of the instrument in a number of retrieval simulations. These precision levels can be compared with user requirements. A comparison of precision estimates with the literature and an analysis of the dependence on the a priori error in the fluorescence emission indicate that aerosol parameters can be retrieved in the presence of chlorophyll fluorescence: if fluorescence is present, fluorescence emissions should be included in the state vector to avoid biases in retrieved aerosol parameters.

  18. Characterization of red-shifted phycobilisomes isolated from the chlorophyll f-containing cyanobacterium Halomicronema hongdechloris.

    Science.gov (United States)

    Li, Yaqiong; Lin, Yuankui; Garvey, Christopher J; Birch, Debra; Corkery, Robert W; Loughlin, Patrick C; Scheer, Hugo; Willows, Robert D; Chen, Min

    2016-01-01

    Phycobilisomes are the main light-harvesting protein complexes in cyanobacteria and some algae. It is commonly accepted that these complexes only absorb green and orange light, complementing chlorophyll absorbance. Here, we present a new phycobilisome derived complex that consists only of allophycocyanin core subunits, having red-shifted absorption peaks of 653 and 712 nm. These red-shifted phycobiliprotein complexes were isolated from the chlorophyll f-containing cyanobacterium, Halomicronema hongdechloris, grown under monochromatic 730 nm-wavelength (far-red) light. The 3D model obtained from single particle analysis reveals a double disk assembly of 120-145 Å with two α/β allophycocyanin trimers fitting into the two separated disks. They are significantly smaller than typical phycobilisomes formed from allophycocyanin subunits and core-membrane linker proteins, which fit well with a reduced distance between thylakoid membranes observed from cells grown under far-red light. Spectral analysis of the dissociated and denatured phycobiliprotein complexes grown under both these light conditions shows that the same bilin chromophore, phycocyanobilin, is exclusively used. Our findings show that red-shifted phycobilisomes are required for assisting efficient far-red light harvesting. Their discovery provides new insights into the molecular mechanisms of light harvesting under extreme conditions for photosynthesis, as well as the strategies involved in flexible chromatic acclimation to diverse light conditions. PMID:26514405

  19. Identification of a peroxisomal-targeted aldolase involved in chlorophyll biosynthesis and sugar metabolism in rice.

    Science.gov (United States)

    Zhang, Fei; Zhang, Pan; Zhang, Yu; Wang, Shouchuang; Qu, Lianghuan; Liu, Xianqing; Luo, Jie

    2016-09-01

    Chlorophyll plays remarkable and critical roles in photosynthetic light-harvesting, energy transduction and plant development. In this study, we identified a rice Chl-deficient mutant, ygdl-1 (yellow green and droopy leaf-1), which showed yellow-green leaves throughout plant development with decreased content of Chls and carotene and an increased Chl a/b ratio. The ygdl-1 mutant also exhibited severe defects in chloroplast development, including disorganized grana stacks. Sequence analysis revealed that the mutant contained a T-DNA insertion within the promoter of a fructose-1,6-bisphosphate aldolase (OsAld-Y), which dramatically reduced the OsAld-Y mRNA level, and its identity was verified by transgenic complementation. Real-time PCR analysis showed that the expression levels of genes associated with chlorophyll biosynthesis and chloroplast development were concurrently altered in the ygdl-1 mutant. The expression of OsAld-Y-GFP fusion protein in tobacco epidermal cells showed that OsAld-Y was localized to the peroxisome. In addition, the analysis of primary carbon metabolites revealed the significantly reduced levels of sucrose and fructose in the mutant leaves, while the glucose content was similar to wild-type plants. Our results suggest that the OsAld-Y participates in Chl accumulation, chloroplast development and plant growth by influencing the photosynthetic rate of leaves and the sugar metabolism of rice. PMID:27457997

  20. Effect of Zn stresses on physiology, growth, Zn accumulation, and chlorophyll of Phyllostachys pubescen s.

    Science.gov (United States)

    Peng, Danli; Shafi, Mohammad; Wang, Ying; Li, Song; Yan, Wenbo; Chen, Junren; Ye, Zhengqian; Liu, Dan

    2015-10-01

    The effects of Zinc (Zn) on lipid peroxidation, antioxidative enzymes, growth, Zn accumulation, and leaf chlorophyll of Phyllostachys pubescens (Pradelle) Mazel ex J.Houz. were investigated in two greenhouse experiments. Hydroponics experiment with Zn application of 0, 20, 100, and 400 μM revealed that lower concentration of Zn in solution led to increased malondialdehyde (MDA) and proline contents but inhibited SOD activity in all treatments. P. pubescens had showed strong ability to accumulate Zn in stems and reached maximum level at 100 μM with 7.91-fold increase compared with control. In pot experiment, treatment with Zn ranged from 0, 200, 400, 800, 1,600, to 3,200 mg kg(-1). Application of 800 mg kg(-1) revealed 116, 24.6, and 28.3 times increase in Zn concentration of roots, stems, and leaves, respectively. Growth and chlorophyll contents of plants in pots were better promoted at 400 mg kg(-1) Zn, with 60.5 and 30.9 % enhanced roots and shoot compared with control. The bioaccumulation factor (BAF) was in the sequence of stem > roots > leaves. The translocation factor (TF) of stem was higher than leaves. PMID:26002363

  1. Cationic chlorophyl derivatives with SOD mimicking activity suppress the proliferation of human ovarian cancer cells.

    Science.gov (United States)

    Kobayashi, Y; Maniki, M; Nakamura, K

    1996-06-01

    Derivatives of chlorophyl, e.g. Fe-chlorin e6-Na, alpha, beta, gamma, delta-Tetraphenylporphine-tetrasulfonic acid disulfonic acid salt tetrahydrate (Fe-TPPTS) and alpha, beta, gamma, delta-Tetrakis (4-N-trimethylaminophenyl) porphine, tetra (p-toluensulfonate (Fe-TTMAPP), express SOD mimicking activity. Examination was made of suppressive effects of human cancer cell lines by derivatives of chlorophyl. Fe-TPPTS and Fe-TTMAPP suppressed proliferation of the human ovarian cancer cell lines but Fe-chlorin e6-Na failed to suppress the proliferation. Lipid peroxide was increased by application of Fe-TPPTS and Fe-TTMAPP, but decreased by application of Fe-chlorin e6-Na. SOD activity of the cancer cells did not change by application of these drugs. TPPTS and TTMAPP have a cationic charge but Fe-chlorin e6-Na has an anionic charge. It is suggested that charge of these drugs relates to the suppressive effects of the cancer cell proliferation. PMID:10851538

  2. Error in interpreting field chlorophyll fluorescence measurements: heat gain from solar radiation

    International Nuclear Information System (INIS)

    Temperature and chlorophyll fluorescence characteristics were determined on leaves of various horticultural species following a dark adaptation period where dark adaptation cuvettes were shielded from or exposed to solar radiation. In one study, temperature of Swietenia mahagoni (L.) Jacq. leaflets within cuvettes increased from approximately 36C to approximately 50C during a 30-minute exposure to solar radiation. Alternatively, when the leaflets and cuvettes were shielded from solar radiation, leaflet temperature declined to 33C in 10 to 15 minutes. In a second study, 16 horticultural species exhibited a lower variable: maximum fluorescence (Fv:Fm) when cuvettes were exposed to solar radiation during the 30-minute dark adaptation than when cuvettes were shielded. In a third study with S. mahagoni, the influence of self-shielding the cuvettes by wrapping them with white tape, white paper, or aluminum foil on temperature and fluorescence was compared to exposing or shielding the entire leaflet and cuvette. All of the shielding methods reduced leaflet temperature and increased the Fv:Fm ratio compared to leaving cuvettes exposed. These results indicate that heat stress from direct exposure to solar radiation is a potential source of error when interpreting chlorophyll fluorescence measurements on intact leaves. Methods for moderating or minimizing radiation interception during dark adaptation are recommended. (author)

  3. Data for iTRAQ-based quantitative proteomics analysis of Brassica napus leaves in response to chlorophyll deficiency

    Directory of Open Access Journals (Sweden)

    Pu Chu

    2015-03-01

    Full Text Available The essential pigment chlorophyll (Chl plays important roles in light harvesting and energy transfer during photosynthesis. Here we present the data from a comparative proteomic analysis of chlorophyll-deficient Brassica napus mutant cde1 and its corresponding wild-type using the iTRAQ approach (Pu Chu et al., 2014 [1]. The distribution of length and number of peptides, mass and sequence coverage of proteins identified was calculated, and the repeatability of the replicates was analyzed. A total of 443 differentially expressed proteins were identified in B. napus leaves, including 228 down-accumulated proteins mainly involved in photosynthesis, porphyrin and chlorophyll metabolism, biosynthesis of secondary metabolites, carbon fixation and 215 up-accumulated proteins that enriched in the spliceosome, mRNA surveillance and RNA degradation.

  4. A Reassessment of the Integrated Impact of Tropical Cyclones on Surface Chlorophyll in the Western Subtropical North Atlantic

    Energy Technology Data Exchange (ETDEWEB)

    Foltz, Gregory R.; Balaguru, Karthik; Leung, Lai-Yung R.

    2015-02-28

    The impact of tropical cyclones on surface chlorophyll concentration is assessed in the western subtropical North Atlantic Ocean during 1998–2011. Previous studies in this area focused on individual cyclones and gave mixed results regarding the importance of tropical cyclone-induced mixing for changes in surface chlorophyll. Using a more integrated and comprehensive approach that includes quantification of cyclone-induced changes in mixed layer depth, here it is shown that accumulated cyclone energy explains 22% of the interannual variability in seasonally-averaged (June–November) chlorophyll concentration in the western subtropical North Atlantic, after removing the influence of the North Atlantic Oscillation (NAO). The variance explained by tropical cyclones is thus about 70% of that explained by the NAO, which has well-known impacts in this region. It is therefore likely that tropical cyclones contribute significantly to interannual variations of primary productivity in the western subtropical North Atlantic during the hurricane season.

  5. Modified methods for defining the chlorophyll concentration in the sea using submersible fluorimeters - Theoretical and quantitative analysis

    Science.gov (United States)

    Ostrowska, Mirosława; Stoń-Egiert, Joanna; Woźniak, Bogdan

    2015-10-01

    The paper analyses the reliability of fluorimetric methods for determining chlorophyll concentrations in the sea using a submersible fluorimeter. To this end, such concentrations were measured with a bbe FluoroProbe spectrofluorimeter as well as standard methods in a range of Baltic basins of different trophic index. This analysis shows that fluorimetrically determined chlorophyll concentrations are usually slightly lower than those obtained with standard methods and that the error increases with rising trophic index. Similar tendencies are observed in relation to measurements carried out with different types of fluorimeters and in different waters. Probably due to the nonlinearity of the relationship between the concentration of chlorophyll a and the intensity of its fluorescence, this can be explained by the changes in the fluorescence quantum yield and package effect function with trophic index. It is therefore recommended that the internal algorithms of fluorimeters be recalibrated in the manner suggested.

  6. Towards a Non-Perturbative Theory of Optical Spectra of Pigment Protein Complexes: Application to the Water Soluble Chlorophyll Protein

    International Nuclear Information System (INIS)

    Full text: We present a theory of optical spectra of pigment-protein complexes that allows to include both the excitonic and the exciton-vibrational coupling on an equal footing. The theory is applied to two different types of the water soluble chlorophyll binding protein (WSCP) containing chlorophyll dimers. First, it is tested in simulation of optical spectra of class IIb WSCP with known crystal structure, and then it is applied to class IIa WSCP with unknown structure, in order to check whether a similar arrangement of chlorophylls as in type IIb WSCP can be assumed. Using a homology modeling of the unknown structure in combination with quantum chemical/ electrostatic calculations we propose an explanation of the 10 nm redshift observed of its optical bands with respect to class IIb WSCP. (author)

  7. Chlorophyll and pheophytin content in needles of different age of trees growing under conditions of chronic industrial pollution

    Directory of Open Access Journals (Sweden)

    Teresa Gowin

    2015-05-01

    Full Text Available Chlorophyll and pheophytin content was determined by means of Vernon method (Vernon, 1960 in needles of different age. Needles of Pinus strobus L., Pinus nigra Arnd., Pinus silvestris L., and Pseudotsuga menziesii Franco growing under conditions of chronic industrial pollution as well as under unpolluted conditions were examined. High pheophytin content was found in needles of trees growing under the conditions of chronic pollution. The youngest needles always showed the highest pheophytin content' as related to Chlorophyll content. The examined species showed different degree of Chlorophyll decomposition under the influence of polluted environment. Trees growing under control environment showed small and similar amounts of pheophytin in needles of different age. Pheophytin content does not seem to be a convenient indicator to test the effect of pollution before visual symptoms occur, since the method is very labourious and plant material very variable.

  8. Effect of UV-C radiation and hypergravity on germination, growth and content of chlorophyll of wheat seedlings

    Science.gov (United States)

    Rupiasih, N. Nyoman; Vidyasagar, Pandit B.

    2016-03-01

    An investigation of the effects of UV-C radiation and hypergravity on germination, growth and content of chlorophyll of wheat seedlings has been done. The UV-C irradiation periods of exposure were 30, 60, 90, 120 and 180 minutes. The hypergravity used were 1000 g, 2000 g and 2500 g. The combination treatment is UV-C irradiation for 180 min followed by each hypergravity. The results showed that irradiation of UV-C on wheat seeds have stimulated the seed germination, but hypergravity and combination treatments on wheat seeds have inhibited the seed germination. Those treatments gave negative effects to growth rate, the content of chlorophyll a, b and total chlorophyll of wheat seedlings.

  9. Evaluating Chlorophyll-a Changes During Algal Bloom in Three Gorges Reservoir Using an Extended WASP Model

    Directory of Open Access Journals (Sweden)

    Jian Li

    2016-01-01

    Full Text Available Algal bloom in Three Gorges Reservoir (TGR and one of its tributaries, Xiangxi River (XR, have become major concerns and the dynamic changes of such events were investigated using the hydrodynamic model SELFE and the extended Water Quality Analysis Simulation Program (WASP model to address nutrient and biomass dynamics. The model has taken into consideration the surface wind, heat fluxes, oxygen exchanges, solar radiations and boundary conditions from main river channel and tributaries. As an extension to our previous work, this study aimed to report in more detailed the result of chlorophyll-a simulations, where the field observed data of algal blooms in TGR in 2007 was used for calibration and the horizontal and vertical distributions of phytoplankton biomass (based on chlorophyll-a were presented. It was found that the chlorophyll-a concentration characterized as algal biomass was influenced by many complex factors. Further study results are yet to be reported.

  10. Effects of a coal-fired power plant on the rock lichen Rhizoplaca melanophthalma: chlorophyll degradation and electrolyte leakage

    Science.gov (United States)

    Belnap, Jayne; Harper, Kimball T.

    1990-01-01

    Chlorophyll degradation and electrolyte leakage were measured for the umbilicate desert lichen Rhizoplaca melanophthalma (Ram.) Leuck. & Poelt in the vicinity of a coal-fired power plant near Page, Arizona. Patterns of lichen damage indicated by chlorophyll degradation were similar to those indicated by electrolyte leakage. Regression analyses of chlorophyll degradation as well as electrolyte leakage on distance from the power plant were significant (p power plant. Mean values for both variables at the two sites closest to the power plant (7 and 12 km) differed significantly from values for the two sites farthest from the plant (21 and 42 km; p power plant combine with local weather factors to produce the observed levels of damage.

  11. Growth response and toxic effects of three antibiotics on Selenastrum capricornutum evaluated by photosynthetic rate and chlorophyll biosynthesis

    Institute of Scientific and Technical Information of China (English)

    Binyang Liu; Weiqiu Liu; Xiangping Nie; Chao Guan; Yufeng Yang; Zhaohui Wang; Wei Liao

    2011-01-01

    The effects of three types of antibiotics (erythromycin,ciprofloxacin and sulfamethoxazole) on the photosynthesis of freshwater algae,Selenastrum capricornutum Printz,were investigated by determining the growth rate,chloroplast pigments content,seven main precursors (including δ-aminolevulinic acid,porphobilinogen,uroporphyrinogen Ⅲ,coproporphyrinogen Ⅲ,protoporphyrin Ⅸ,Mg-proporphyrin Ⅸ and protochlorophyllide),and photosynthetic rate during chlorophyll biosynthesis.The antibiotics significantly decreased the growth rate,chlorophyll content,and photosynthetic rate.Erythromycin induced a decreasing effect at a concentration of 0.06 mg/L,while ciprofloxacin and sulfamethoxazole achieved the same results at concentrations higher than 1.5 mg/L.Only erythromycin significantly inhibited chlorophyll biosynthesis,which indicated that it was considerably more toxic to S.capricornutum than ciprofloxacin and sulfamethoxazole,and may pose a high potential risk to aquatic ecosystems.

  12. Comparison of green and variegated foliage plant species based on chlorophyll fluorescence parameters under different light intensities

    International Nuclear Information System (INIS)

    To compare green and variegated foliage plants namely; Hedera helix, Ardisia pusilla and Scindapsus aureus were treated under three different light intensities (2, 10 and 20 micro mol-m-2-s-1) using florescent lights for three months, and photosynthetic characteristics and chlorophyll content were measured. IMAGING-PAM chlorophyll fluorescence system was used to determine photosynthetic characteristics. The results showed that Fv/Fm (maximal PS-II quantum yield) and Y (II) (effective PS-II quantum yield) values were lower in variegated species compared to those in green species at 2 micro mol-m-2-s-1 light intensity. Although, Fv/Fm and Y (II) values in variegated S. aureus was lower than variegated H. helix, but variegated S. aureus survived and Hedera helix plants died after low light treatment. In contrast, Fv/Fm and Y (II) values were increased in green and variegated species with increasing the light intensity, except Fv/Fm value for variegated S. aureus which was slightly decreased at 20 micro mol-m-2-s-1 light intensity. The ETR (electron transport rate) value was also lower in both green and variegated species at 2 micro mol-m-2-s-1 intensity. ETR values saturated in green and variegated plants with increasing the light intensity. Higher level of chlorophyll was obtained in green species compared to variegated species for both low and high light intensity treatments. Chlorophyll content in green species decreased at 20 micro mol-m-2-s-1 light intensity, whereas in variegated species, chlorophyll content increased with increasing the light intensities. The results of chlorophyll fluorescence parameters showed that especially low light intensity created stress condition in variegated foliage plants compared to green plants, and affected the normal growth and development. (author)

  13. [Flag leaf photosynthetic characteristics, change in chlorophyll fluorescence parameters, and their relationships with yield of winter wheat sowed in spring].

    Science.gov (United States)

    Xu, Lan; Gao, Zhi-qang; An, Wei; Li, Yan-liang; Jiao, Xiong-fei; Wang, Chuang-yun

    2016-01-01

    With five good winter wheat cultivars selected from the middle and lower reaches of Yangtze River and Southwest China as test materials, a field experiment in Xinding basin area of Shanxi Province was conducted to study the photosynthetic characteristics, chlorophyll content, and chlorophyll fluorescence parameters of flag leaf at different sowing dates, as well as the correlations between these indices and yield for two years (2013-2014). The results showed that the difference in most fluorescence parameters except chlorophyll content among cultivars was significant. The correlations between these fluorescence parameters and yield were significant. The variation coefficient of chlorophyll (Chl) content was low (0.12-0.17), and that of performance index based on absorption (PIabs) was high (0.32-0.39), with the partial correlation coefficients of them with grain yield from 2013 to 2014 ranged in 0.70-0.81. Under the early sowing condition, the grain yield positively correlated with PIabs at flowering and filling stages and chlorophyll content at grain filling stage, but negatively correlated with the relative variable fluorescence at I point (Vi) at grain filling stage. About 81.1%-82.8% of grain yield were determined by the variations of PIabs, Chl, and Vi. Wheat cultivars had various performances in the treatments with different sowing dates and a consistent trend was observed in the two experimental years. Among these 5 cultivars, Yangmai 13 was suitable for early sowing, with the flag leaf photosynthetic rate (Pn), Chl, most fluorescence parame-ters, and grain yield showed obviously high levels. In conclusion, under early sowing condition chlorophyll content at grain filling stages, PIabs at flowering and filling stages, and Pn were important indices for selecting wheat cultivars with high photosynthetic efficiency. PMID:27228602

  14. Remote sensing of chlorophyll a fluorescence of vegetation canopies. 2. Physiological significance of fluorescence signal in response to environmental stresses

    International Nuclear Information System (INIS)

    Measurements of laser-induced chlorophyll fluorescence of living leaves were compared to ecophysiological parameters, both in near and far field conditions. Near field measurements were carried out with a two-wavelength portable fluorometer, both in the laboratory and in the field. Results show significant changes of the 690 nm and 730 nm chlorophyll fluorescence bands in different environmental conditions. Water stress and carboxylation limitations also affect the fluorescence spectra. Far field measurements from a ground-operated fluorescence LIDAR system confirm those results. The F690 / F730 fluorescence ratio is then demonstrated as a good index for vegetation remote sensing. (author)

  15. Salt stress change chlorophyll fluorescence in mango Estresse salino altera a fluorescência da clorofila em mangueira

    OpenAIRE

    Cicero Cartaxo de Lucena; Dalmo Lopes de Siqueira; Hermínia Emilia Prieto Martinez; Paulo Roberto Cecon

    2012-01-01

    This study evaluated the tolerance of mango cultivars 'Haden', 'Palmer', 'Tommy Atkins' and 'Uba' grafted on rootstock 'Imbú' to salt stress using chlorophyll fluorescence. Plants were grown in modified Hoagland solution containing 0, 15, 30, and 45 mmol L-1 NaCl. At 97 days the parameters of the chlorophyll fluorescence (F0, Fm, Fv, F0/Fm, Fv/Fm, Fv'/Fm', ΦPSII = [(Fm'-Fs)/(Fm')], D = (1- Fv'/Fm') and ETR = (ΦPSII×PPF×0,84×0,5) were determined. At 100 days, the leaf emission and le...

  16. NOA1 Functions in a Temperature-Dependent Manner to Regulate Chlorophyll Biosynthesis and Rubisco Formation in Rice

    OpenAIRE

    Yang, Qiaosong; He, Han; Li, Heying; Tian, Hua; Zhang, Jianjun; Zhai, Liguang; Chen, Jiandong; Wu, Hong; Yi, Ganjun; He, Zheng-Hui; Peng, Xinxiang

    2011-01-01

    NITRIC OXIDE-ASSOCIATED1 (NOA1) encodes a circularly permuted GTPase (cGTPase) known to be essential for ribosome assembly in plants. While the reduced chlorophyll and Rubisco phenotypes were formerly noticed in both NOA1-supressed rice and Arabidopsis, a detailed insight is still necessary. In this study, by using RNAi transgenic rice, we further demonstrate that NOA1 functions in a temperature-dependent manner to regulate chlorophyll and Rubisco levels. When plants were grown at 30°C, the c...

  17. Changes in chlorophyll content and fluorescence and fruit yield contributing traits in different genotypes of strawberry (Fragaria x ananassa DUCH.)

    OpenAIRE

    Elżbieta Kaczmarska; Władysław Michałek

    2014-01-01

    Analysis of changes in chlorophyll fluorescence parameters in strawberry leaves was based on a field experiment performed in the years 2009–2010. Ten genotypes including 5 cultivars: ‘Kent’, ‘Teresa’, ‘Senga Sengana’, ‘Chandler’ and the breeding clone 1387 as well as their inbred progeny, were the object of the study. During the experiment the following indicators were evaluated: chlorophyll a and b content in fresh leaf mass as well as fluorescence parameters: minimum (F0) and maximum fluore...

  18. Effects of Light Intensity on Development and Chlorophyll Content in the Arabidopsis Mutant Plants with Defects in Photosynthesis

    OpenAIRE

    E.Yu. Garnik; D.V. Deeva; V.I. Belkov; V.I. Tarasenko; Yu.M. Konstantinov

    2015-01-01

    The developmental stages and adaptability to different light intensity (150 µmol*m-2*s-1 and 100 µmol*m-2*s-1) in Arabidopsis mutant lines with defects of photosynthetic apparatus were analyzed. Plant development in the mutant lines depended on the light intensity to varying degrees. Lines ch1-1 (lack of the chlorophyllide a oxygenase) and rtn16 (decreased chlorophyll a and b amounts) were the most susceptible to the light decrease. No one of the investigated lines demonstrated chlorophyll a/...

  19. The impact of turbulence and phytoplankton dynamics on foam formation, seawater viscosity and chlorophyll concentration in the eastern English Channel

    Directory of Open Access Journals (Sweden)

    Irma Kesaulya

    2008-06-01

    Full Text Available The space-time dynamics of chlorophyll a concentration and seawater excess viscosity has been investigated in the hydrographically contrasting inshore and offshore water masses of the eastern English Channel. This was done during the phytoplankton spring bloom dominated by Phaeocystis globosa before and after the very large-scale formation of foam induced by an increase in wind-driven turbulence and the related wave breakings. The results suggest that the dynamics of chlorophyll a concentration and seawater excess viscosity are differentially controlled by the formation of foam through the intensity of the spring bloom and wind-generated turbulence.

  20. Combining Principal Component Regression and Artificial Neural Network to Predict Chlorophyll-a Concentration of Yuqiao Reservoir’s Outflow

    Institute of Scientific and Technical Information of China (English)

    张旋; 王启山; 于淼; 吴京

    2010-01-01

    In order to investigate the eutrophication degree of Yuqiao Reservoir, a hybrid method, combining principal component regression (PCR) and artificial neural network (ANN), was adopted to predict chlorophyll-a concentration of Yuqiao Reservoir’s outflow. The data were obtained from two sampling sites, site 1 in the reservoir, and site 2 near the dam. Seven water variables, namely chlorophyll-a concentration of site 2 at time t and that of both sites 10 days before t, total phosphorus(TP), total nitrogen(TN),...