Chlorophyll Meter
Mostrando 25-36 de 44 artigos, teses e dissertações.
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25. ESTIMATE OF NUTRITIONAL STATE OF FLOODED RICE / ESTIMATIVA DO ESTADO NUTRICIONAL DE ARROZ IRRIGADO POR ALAGAMENTO
The difficulty to predict the intensity of soil properties alterative by soil flooding frequently makes the interpretation of the soil analysis results inaccurate when considering nutrients availability to the plants. Complementary methods of soil analysis, as leaf tissue analysis, chlorophyll meter and the leaf color chart can be used in order to estimate p
Publicado em: 2007
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26. Cultivo em campo de Coffea arabica L. cv. Obatã a pleno sol x sombreamento parcial: avaliações bioquímicas, fisiológicas e nutricionais / Field growth of Coffea arabica L. cv. Obatã under full x partial shade: biochemical, physiological and nutritional evaluations
Plants of Arabian coffee with 4,5 years of age, had been compared from August to December growing under full sun and under natural shade conditions. The plants presented significant differences in growth terms and physiological and biochemical's aspects. The nitrogen supply in the October month provided a significant increase on levels of amino acid tota
Publicado em: 2007
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27. Photosystem Stoichiometry and Excitation Distribution in Chloroplasts from Surface and Minus 20 Meter Blades of Macrocystis pyrifera, the Giant Kelp 1
The photochemical apparatus organization in the thylakoid membrane of Macrocystis pyrifera, the giant kelp, was investigated. Chloroplasts were isolated from surface and minus 20 meter blades. Photosynthetic electron-transport complex quantitation revealed ratios of photosystem (PS) II/cytochrome b6-f/PSI = 1.8:3.3:1.0 in surface and 2.2:2.3:1.0 in minus 20
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28. Chlorophyll-Protein Complexes from the Red-Tide Dinoflagellate, Gonyaulax polyedra Stein 1: Isolation, Characterization, and the Effect of Growth Irradiance on Chlorophyll Distribution
A comparision of high (330 microeinsteins per meter squared per second) and low (80 microeinsteins per meter squared per second) light grown Gonyaulax polyedra indicated a change in the distribution of chlorophyll a, chlorophyll c2, and peridinin among detergent-soluble chlorophyll-protein complexes. Thylakoid fractions were prepared by sonication and centri
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29. Effects of Growth Irradiance Levels on the Ratio of Reaction Centers in Two Species of Marine Phytoplankton 1
Cells of two species of single-celled marine algae, the diatom Skeletonema costatum (Greve), Cleve, and the chlorophyte Dunaliella tertiolecta Butcher, were cultured in white light of high (500-600 microeinsteins per square meter per second) and low (30 microeinsteins per square meter per second) intensity. For both algal species, cells grown at low light le
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30. Blue-Light Regulation of Epicotyl Elongation in Pisum sativum1
Blue light is known to induce suppression of stem elongation. To avoid the complication of blue-light-induced transformation of phytochrome we have adapted the procedure of measuring blue-light-induced suppression of stem elongation in Pisum sativum L. var Alaska grown under continuous red light. The resulting fluence-response curve for suppression of epicot
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31. Light-Dependent Accumulation of Radiolabeled Plastid-Encoded Chlorophyll a-Apoproteins Requires Chlorophyll a1: I. Analysis of Chlorophyll-Deficient Mutants and Phytochrome Involvement
The accumulation of radiolabeled plastid-encoded chlorophyll a-apoproteins is light dependent and is controlled at a posttranscriptional level. Illumination of dark-grown barley (Hordeum vulgare L.) with a brief pulse of red light induced the accumulation of radiolabeled chlorophyll a-apoproteins in subsequent protein synthesis assays. The induction of radio
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32. Photosynthetic Apparatus of Pea Thylakoid Membranes 1: Response to Growth Light Intensity
We investigated the effect of growth light intensity on the photosynthetic apparatus of pea (Pisum sativum) thylakoid membranes. Plants were grown either in a growth chamber at light intensities that ranged from 8 to 1050 microeinsteins per square meter per second, or outside under natural sunlight. In thylakoid membranes we determined: the amounts of active
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33. Image Analysis of Chlorophyll Fluorescence Transients for Diagnosing the Photosynthetic System of Attached Leaves
A new image instrumentation system for quantitative analysis of the rapid change in intensity of chlorophyll fluorescence during dark-light transition (CFI, chlorophyll fluorescence induction), which is a sensitive indicator of the various reactions of photosynthesis, was developed and its performance was evaluated. This system made it possible to resolve CF
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34. Enhancement of the Stomatal Response to Blue Light by Red Light, Reduced Intercellular Concentrations of CO2, and Low Vapor Pressure Differences 1
The effects of environmental parameters on the blue light response of stomata were studied by quantifying transient increases in stomatal conductance in Commelina communis following 15 seconds by 0.100 millimole per square meter per second pulses of blue light. Because conductance increases were not observed following red light pulses of the same or greater
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35. Chilling-Enhanced Photooxidation 1: Evidence for the Role of Singlet Oxygen and Superoxide in the Breakdown of Pigments and Endogenous Antioxidants
Chilling temperatures (5°C) and high irradiance (1000 microeinsteins per square meter per second) were used to induce photooxidation in detached leaves of cucumber (Cucumis sativus L.), a chilling-sensitive plant. Chlorophyll a, chlorophyll b, β carotene, and three xanthophylls were degraded in a light-dependent fashion at essentially the same rate. Lipid
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36. Increased Thermal Deactivation of Excited Pigments in Pea Leaves Subjected to Photoinhibitory Treatments
The photoacoustic technique was used to monitor thermal deexcitation of the photosynthetic pigments in intact pea leaves (Pisum sativum L.) submitted to photoinhibitory treatments. When the leaves were exposed to photon flux densities above 1000 micromoles per square meter per second, the amplitude of the photothermal component of the in vivo photoacoustic s