Technique of the Modulated Chlorophyll Fluorescence: Basic Concepts, Useful Parameters, and Some Applications

K. Roháček, M. Barták

Photosynthetica 1999, 37(3):339 | DOI: 10.1023/A:1007172424619

The review summarizes basic information about slow and fast chlorophyll (Chl) a fluorescence induction kinetics (FIK) recorded using fluorimeters working on a principle of the pulse amplitude modulation (PAM) of a Chl fluorescence signal. It explains fundamental principles of the measuring technique, evaluates the terminology, symbols, and parameters used. Analysis of Chl FIK resulting in a set of Chl fluorescence parameters (FPs) provides qualitative and quantitative information about photosynthetic processes in chloroplasts. Using FPs, one can describe the functioning of the photosynthetic apparatus under different internal and external conditions....

Plant Lipid Biosynthesis. Fundamentals and Agricultural Applications

N. Wilhelmová

Photosynthetica 1999, 37(3):364 | DOI: 10.1023/A:1007128315049

Greening of Peas: Parallel Measurements of 77 K Emission Spectra, OJIP Chlorophyll a Fluorescence Transient, Period Four Oscillation of the Initial Fluorescence Level, Delayed Light Emission, and P700

A. Srivastava, R.J. Strasser, Govindjee

Photosynthetica 1999, 37(3):365 | DOI: 10.1023/A:1007199408689

Irradiation of etiolated leaves leads to their greening. Although this problem has a long history, the question of whether the intermittent irradiation (IMI) grown plants have fully functional reaction centres as well as the oxygen clock, before exposure to continuous irradiation (CI), had not been resolved. To answer this question, as well as to analyze the development of the two photosystems, the following parallel measurements were made: (1) Emission spectra at 77 K; (2) OJIP chlorophyll (Chl) a fluorescence transient; (3) period 4 oscillation in the flash number dependence of initial fluorescence F₀ (at 50...

Osmotic and Atmospheric Dehydration Effects in the Lichens Hypogymnia Physodes, Lobaria Pulmonaria, and Peltigera Aphthosa: An in vivo Study of the Chlorophyll Fluorescence Induction

M. Jensen, Samira Chakir, G.B. Feige

Photosynthetica 1999, 37(3):393 | DOI: 10.1023/A:1007151625527

Inactivation of photosynthesis during atmospheric and osmotic (highly concentrated NaCl or sucrose solutions) dehydration was monitored by measurement of chlorophyll fluorescence induction (OIP-phase, Kautsky-curves) in three lichen species. The induction curves were changed in a very similar way by all three treatments. All dehydration effects were rapidly reversible after rehydration. At relatively mild water stress, the rise time to the transient peak F_p was prolonged, and the variable part of fluorescence was diminished. In addition, at severe water stress, a considerable decline of the F₀ value was observed. For NaCl treatment...

The Photosynthesis and Chlorophyll a Fluorescence in Seedlings of Kandelia Candel (L.) Druce Grown under Different Nitrogen and NaCl Controls

Wen-Yuan Kao, Hung-Chieh Tsai

Photosynthetica 1999, 37(3):405 | DOI: 10.1023/A:1007103709598

Kandelia candel (L.) Druce is the dominant mangrove species on the west coast of northern Taiwan. We have measured the net photosynthetic rate (P _N) and chlorophyll (Chl) a fluorescence of seedlings grown at combinations of two nitrogen (0.01 and 0.1 mM) and two NaCl (250 and 430 mM NaCl) controls. With the same nitrogen level, seedlings grown at higher salinity (HS) had a significantly lower P _N and stomatal conductance (g _s) than those at lower salinity (LS). An increase in nitrogen availability significantly elevated P _N and g _s of the LS-grown...

Effect of Rhizobium Sp. Inoculation on N₂-Fixing and Photosynthetic Activities of Two Cowpea [Vigna unguiculata (L.) Walp.] Genotypes

D. Lippi, M.R. De Paolis, M. Osmi, F. Pietrini, T. Pietrosanti, M.C. Villani, A. Massacci

Photosynthetica 1999, 37(3):413-422 | DOI: 10.1023/A:1007155710506

Time course of symbiotic N₂-fixing and photosynthetic activities during vegetative growth from 30 d after plantation until pod set was measured in the CB5 and 7964 cowpea [Vigna unguiculata (L.) Walp.] genotypes of contrasting senescence traits. At emergence, seedlings were inoculated with a "non-cowpea miscellany" Rhizobium strain generally used to inoculate Cicer arietinum. Maximum N₂-fixing activity occurred in inoculated CB5 and 7964 plants about 54 and 68 d after plantation, respectively. A similar temporal shift of maximum was found for net photosynthetic rate (P _N), confirming a good...

Glycinebetaine Stabilizes Photosystem 1 and Photosystem 2 Electron Transport in Spinach Thylakoid Membranes Against Heat Inactivation

Y.M. Allakhverdieva, M.D. Mamedov, N. Ferimazova, G.C. Papageorgiou, R.A. Gasanov

Photosynthetica 1999, 37(3):423-432 | DOI: 10.1023/A:1007159827344

Glycinebetaine, a compatible osmolyte of halotolerant plants and bacteria, partially protected photosystem (PS) 1 and PS2 electron transport reactions against thermal inactivation but with different efficiencies. In its presence, the temperature for half-maximal inactivation (t_1/2) was generally shifted downward by 3-12 °C. Glycinebetaine stabilized photoinduced oxygen evolving reactions of PS2 by protecting the tetranuclear Mn cluster and the extrinsic proteins of this complex. A weaker, although noticeable, stabilizing effect was observed in photoinduced PS2 electron transport reactions that did not originate in the oxygen-evolving complex...

Response of Photosynthesis to Radiation and Intercellular CO₂ Concentration in Sun and Shade Shoots of Norway Spruce

M. Šprtová, M.V. Marek

Photosynthetica 1999, 37(3):433 | DOI: 10.1023/A:1007111911415

Functional differentiation of assimilation activity of sun versus shade foliage was analysed in a Norway spruce monoculture stand (age 15 years). The investigated stand density (leaf area index 8.6) and crown structure led to variation in the photosynthetically active photon flux density (PPFD) within the crowns of the sampled trees. At the saturating PPFD, the maximum rate of CO₂ uptake (P _Nmax) of exposed shoots (E-shoots) was 1.7 times that of the shaded shoots (S-shoots). The apparent quantum yield (α) of E-shoots was 0.9 times that of the S-shoots. A lower ability to use excess energy at high PPFD in photosynthesis...

Plant Physiological Ecology

L. Adamec

Photosynthetica 1999, 37(3):446 | DOI: 10.1023/A:1007132415958

Influence of Drought, High Temperature, and Carbamide Cytokinin 4-PU-30 on Photosynthetic Activity of Bean Plants. 1. Changes in Chlorophyll Fluorescence Quenching

I. Yordanov, V. Velikova, T. Tsonev

Photosynthetica 1999, 37(3):447-457 | DOI: 10.1023/A:1007163928253

Fifteen-day-old bean plants (Phaseolus vulgaris L.) grown in a climatic chamber were exposed to water deficit (WD) and high temperature (HT) stresses applied separately or in combination. Changes in chlorophyll fluorescence quenching were investigated. Bean plants that endured mild (42 °C, 5 h for 2 d) WD separately or in combination with HT did not change their q_P and q_N quenching (measured at 25 °C) compared with those of the control. After 5 min testing at 45 °C, q_P in control and droughted plants strongly decreased, while q_P of plants that experienced combined WD+HT stress was insignificantly influenced,...

Radiation Biophysics. 2^nd Ed.

J. Nauš

Photosynthetica 1999, 37(3):458 | DOI: 10.1023/A:1007176230979

UV-B Radiation Mediated Alterations in the Nitrate Assimilation Pathway of Crop Plants 1. Kinetic Characteristics of Nitrate Reductase

T. Balakumar, V. Selvakumar, K. Sathiameena, C. Murugu Ilanchezhian, K. Paliwal

Photosynthetica 1999, 37(3):459-467 | DOI: 10.1023/A:1007116012323

The kinetics and other characteristics of nitrate reductase (NR, EC 1.6.6.1) in cowpea [Vigna unguiculata (L.) Walp.] seedlings irradiated with biologically effective UV-B radiation (280-320 nm, 3.2 W m^-2 s^-1) were recorded. The in vivo and in vitro NR activities were inhibited by 34 and 41 % under UV-B treatment, respectively. Both V_max and K_m for the substrate were enhanced by UV-B radiation. The K_m for nitrate increased from 1.2 to 1.7 mM after the UV-B irradiation. The change in K_m for NADH was from 0.12 to 0.17 mM. The increases in K_m indicate that...

Inherent Variation in Plant Growth. Physiological Mechanisms and Ecological Consequences

J. Čatský

Photosynthetica 1999, 37(3):468 | DOI: 10.1023/A:1007180331888

UV-B Radiation Mediated Alterations in the Nitrate Assimilation Pathway of Crop Plants 2. Kinetic Characteristics of Nitrite Reductase

T. Balakumar, K. Sathiameena, V. Selvakumar, C. Murugu Ilanchezhian, K. Paliwal

Photosynthetica 1999, 37(3):469-475 | DOI: 10.1023/A:1007168029162

Cowpea [Vigna unguiculata (L.) Walp. cv. Co 4] seedlings were subjected to a weighted irradiance of 3.2 W m^-2 s^-1 of biologically effective ultraviolet-B radiation (UV-B, 280-320 nm) and the changes in the kinetic and other characteristics of nitrite reductase (NiR) were recorded. The activity of NiR was hampered by 19 % under UV-B irradiation compared to the control. The UV-B treated plants required higher concentrations of nitrate for the induction of NiR synthesis than the controls. The NiR activity decay kinetics showed that the UV-B treatment significantly lowers the t_1/2 of the enzyme, thereby indicating...

Dynamics of Leaf Photosynthesis. Rapid-Response Measurements and Their Interpretations

J. Čatský

Photosynthetica 1999, 37(3):476 | DOI: 10.1023/A:1007184500028

The Effect of Low Growth Temperature on Hill Reaction and Photosystem 1 Activities and Pigment Contents in Maize Inbred Lines and Their F₁ Hybrids

M. Körnerová, D. Holá

Photosynthetica 1999, 37(3):477-488 | DOI: 10.1023/A:1007120113232

Young plants of maize inbred lines CE777, CE704, and CE810 and their F₁ hybrids displaying a positive heterotic effect in various photosynthetic characteristics were exposed to low temperature during their early growth developmental stage. The photochemical activity of isolated mesophyll chloroplasts and the contents of photosynthetic pigments in leaves of stressed and non-stressed plants were compared with the aim to find out the possible changes in the relationship between parents and hybrids, and to determine the genetic basis of heterosis in F₁ generation. Strong decrease in the content of chlorophylls was observed for all...

The Content of Light-Harvesting Complexes in Different Maize (Ze mays L.) Genotypes

D. Holá

Photosynthetica 1999, 37(3):489-492 | DOI: 10.1023/A:1007172130070

Genetic analysis of the content of light-harvesting complexes of thylakoid membranes was accomplished for the first time during the study of intraspecific variation in photosynthetic characteristics. The existence of genetically determined differences between genotypes together with positive heterosis in F₁ generation was demonstrated.

Maize Leaf Rolling Initiation

D. Fernandez, M. Castrillo

Photosynthetica 1999, 37(3):493-497 | DOI: 10.1023/A:1007124214141

Maize plants of CPB2 and CPB8 hybrids were kept under water deficit for 22 d. In the CPB8 hybrid, leaf rolling initiated at the 9^th d of water deficit period, while in CPB2 hybrid it was at the 15^th d. Both hybrids showed leaf rolling initiation at the same leaf water potential, Ψ_W of -0.480±0.095 MPa. At leaf rolling initiation, the leaf osmotic potential, Ψ_S was -0.730±0.085 MPa in CPB8 and 0.630±0.110 MPa in CPB2. The leaf temperature and stomatal conductance were higher in CPB8 than in CPB2. Values of leaf Ψ_W, ribulose-1,5-bisphosphate carboxylase activity,...