Photosynthesis in Cuscuta Reflexa: A Total Plant Parasite

N. K. Choudhury, D. Sahu

Photosynthetica 1998, 36(1):1 | DOI: 10.1023/A:1007025500452

Photosynthetic properties of Cuscuta species, such as chloroplast ultrastructure, contents of chlorophylls, carotenoids, and plastid proteins, photosystem and CO₂ fixation activities, and photosynthetic genes composition are reviewed.

Fraser, J.: How to Publish in Biomedicine

Z. Šesták

Photosynthetica 1998, 36(1):10 | DOI: 10.1023/A:1007020231828

A Comparison of Photosynthetic Capacity between Myrica Gale var. Tomentosa a Nitrogen-Fixing Shrub, and Co-Occurring Species in an Oligotrophic Moor

K. Maeda, Y. Yamamura, H. Ozawa, Y. Hori

Photosynthetica 1998, 36(1):11-20 | DOI: 10.1023/A:1007054317290

Photosynthetic and transpiration (E) rates, stomatal conductance, and leaf nitrogen content were surveyed for Myrica gale var. tomentosa, a N₂-fixing wetland shrub, Betula platyphylla var. japonica, and Rhododendron japonicum in Ozegahara moor, an oligotrophic moor in Central Japan. Net photosynthetic rate saturated with irradiance (P_max) of M. gale was 15.2-16.5 μmol(CO₂) m^-2 s^-1, higher than those of the other species throughout the growing season. P_max was positively correlated with leaf N content among the three species. The large leaf N content in M. gale was due to N₂-fixation...

The Influence of Increased Solar UV-B Radiation on Magnesium-Deficient Cowpea Seedlings: Changes in the Photosynthetic Characteristics

A. Premkumar, G. Kulandaivelu

Photosynthetica 1998, 36(1):21 | DOI: 10.1023/A:1007006401360

The influence of increased solar UV-B radiation on the photosynthetic characteristics in cowpea seedlings (Vigna unguiculata) grown at optimal (Mg_s) and low (Mg_d) Mg levels were studied. Both higher UV-B and Mg_d treatments caused significant drops of photochemical activities and net CO₂ uptake rates (P_N). Yet the UV-B-induced decrease in the photosynthetic efficiency was lesser in Mg_d seedlings. The leaf Chl a fluorescence measurements proved that after receiving an enhanced UV-B radiation these seedlings showed a significant enhancement in their variable parts. The PSM oscillation of...

Campbell, G.S., Norman, J.M.: An Introduction to Environmental Biophysics

J. Nauš

Photosynthetica 1998, 36(1):30 | DOI: 10.1023/A:1007016114990

Effects of Manganese in Solution Culture on the Growth of Five Deciduous Broad-Leaved Tree Species with Different Successional Characters from Northern Japan

M. Kitao, T.T. Lei, T. Koike

Photosynthetica 1998, 36(1):31 | DOI: 10.1023/A:1007058418199

The effects of four manganese (Mn) concentrations (1, 10, 50, and 100 g m^-3 = Mn₁, Mn₁₀, Mn₅₀, Mn₁₀₀) in solution culture on growth variables were studied for seedlings of five deciduous broad-leaved trees with different successional characteristics and shoot development patterns in northern Japan. The five species were: Betula ermanii, Betula platyphylla var. japonica, and Alnus hirsuta (early-successional species with continuous leaf development), Ulmus davidiana var. japonica (mid-successional species with flush and continuous leaf development), and Acer mono (late-successional species with...

Seasonal Patterns of Photosystem 2 Photochemical Efficiency in Evergreen Sclerophylls and Drought Semi-Deciduous Shrubs under Mediterranean Field Conditions

S. Karavatas, Y. Manetas

Photosynthetica 1998, 36(1):41 | DOI: 10.1023/A:1007010502269

Photochemical efficiency of photosystem 2 (PS2), assessed from in situ chlorophyll (Chl) fluorescence measurements, was seasonally monitored in five evergreen sclerophyll and five malacophyllous drought semi-deciduous species, co-occurring in the same Mediterranean field site. In evergreen sclerophylls, a considerable drop in the variable (F_v) to maximum (F_m) Chl fluorescence ratio coincided with the lowest winter temperatures, indicating low PS2 efficiency during this period. Summer drought caused a comparatively slight decrease in F_v/F_m and only in three of the five evergreen sclerophyll species tested....

Kahru, M., Brown, C.W. (ed.): Monitoring Algal Blooms: New Techniques for Detecting Large-Scale Environmental Change

B. Maršálek

Photosynthetica 1998, 36(1):50 | DOI: 10.1023/A:1007072215898

Protective Action of Abscisic Acid Against the Inhibition of Photosynthesis of Barley Leaves by Bisulphite

C.N. N'Soukpoè-Kossi, A.G. Ivanov, K. Veeranjaneyulu, R.M. Leblanc

Photosynthetica 1998, 36(1):51 | DOI: 10.1023/A:1007062519107

The inhibition of photosynthetic activity by bisulphite was studied in intact leaves of abscisic acid (ABA)-treated and non-treated (control) barley plants. ABA inhibited the photosynthetic process as evidenced by lower values of chlorophyll fluorescence kinetic parameters F_v/F_m (photosystem 2 activity) and R_fd (vitality index, related to the whole photosynthetic activity) compared with ABA-non-treated plants. After bisulphite treatment, the extent of inhibition was smaller in ABA-treated plants than in the control ones indicating a protective effect of ABA. The protective action sites of ABA were the Q_A...

Diurnal Fluctuations in Photochemical Activities of Chloroplasts in Field Grown Cyamopsis Tetragonoloba Seedlings

K. Lingakumar, G. Kulandaivelu

Photosynthetica 1998, 36(1):61 | DOI: 10.1023/A:1007014603178

In field-grown Cyamopsis seedlings, distinct changes were found in the rates of photosystems (PS) 2 and 1 activities at different time of the day. Maximum PS2 activity was at around 11:00 h and decreased thereafter. On the contrary, PS1 activity continued to increase up to 14:00 h and declined in evening hours. Significant energy transfer from PS2 to PS1 was evident during the morning and evening hours of the day whereas a slow excitation of PS2 and energy transfer was favoured during noon hours.

Induction of the Photosystem 2 Dark Formation in Etiolated Leaves with the Involvement of Exogenous Chlorophyllides

V.P. Domanskiï, L.I. Fradkin

Photosynthetica 1998, 36(1):69-78 | DOI: 10.1023/A:1007066720016

The delayed luminescence (DL) of photosystem 2 (PS2) after infiltration of 7-d-old etiolated barley leaves with chlorophyllides (Chlide) a or b followed by 2.5 h dark incubation was studied. Chlide a caused a very weak DL of PS2 just at the beginning of irradiation and the intensity of this DL was not higher when the infiltration medium contained 2 mM of NADPH. Chlide b was a somewhat more efficient inducer of PS2 formation in the dark and NADPH enhanced this efficiency 4.5 times though it did not affect the amount of esterified Chlides. The photoconversion of endogenous Pchlide led to a much higher intensity of the DL in comparison with the infiltration...

Effects of Drought on Photosynthetic Performance and Water Relations of Four Vigna Genotypes

P. Scotti Campos, J.C. Ramalho, J.A. Lauriano, M.J. Silva, M. do Céu Matos

Photosynthetica 1998, 36(1):79 | DOI: 10.1023/A:1007018804086

The effect of drought on plant water relations and photosynthesis of Vigna glabrescens (Vg) and Vigna unguiculata (cvs. 1183, EPACE-1 and Lagoa), which differ in their drought resistance, was compared. With the increase of drought severity, Vg showed a more gradual stomatal closure and maintained significantly higher levels of stomatal conductance (g_s) and photosynthetic activity (P_N) than the other genotypes even when minimum relative water content (RWC) values were observed. Furthermore, Vg was the only genotype able to accumulate significant amounts of proline already under moderate water deficit, what could explain the lower...

Clonal Differences in Photosynthesis in Hevea Brasiliensis Müll. Arg.

K.N. Nataraja, J. Jacob

Photosynthetica 1998, 36(1):89 | DOI: 10.1023/A:1007070820925

The objective of the present investigation was to examine the extent of variations in single leaf net photosynthetic rate (P_N) and its relative dependence on stomatal conductance (g_s) and the mesophyll capacity to fix carbon in 12 clones of the natural rubber plant. There were significant variations in P_N measured at low and saturating photon flux density (PFD); the extent of variation was larger at low than at saturating PFD. The compensation irradiance (CI) and apparent quantum yield of CO₂ assimilation (φ_c) calculated from the P_N/PFD response curves showed significant variations...

Influence of Phosphorus on Gas Exchange and Plant Growth of Two Morphologically Distinct Types of Capsicum Annuum

F.T. Davies Jr., S.A. Duray, L. Phavaphutanon, R.S. Stahl

Photosynthetica 1998, 36(1):99 | DOI: 10.1023/A:1007022904995

Tolerance to phosphorus stress was studied in Capsicum annuum L. Chile ancho cv. San Luis and bell pepper cv. Jupiter plants. Plants were fertilized weekly with Long-Ashton nutrient solution (LANS) modified to supply 0, 11, 22, 44, 66, or 88 g(P) m^-3 (P0, P11, P22, P44, P66, P88). Phosphorus stress occurred in both cultivars at P0 and P11, with reduced plant growth and development. At P0, the lowest percentage of total biomass was directed toward reproductive growth. The root/shoot ratio was greatest at P0, reflecting greater dry matter partitioning to the root system. Growth of 'San Luis' was more sensitive to phosphorus stress than 'Jupiter'....

Prolonged Exposure of Tobacco to a Low Oxygen Atmosphere to Suppress Photorespiration Decreases Net Photosynthesis and Results in Changes in Plant Morphology and Chloroplast Structure

A. Migge, U. Kahmann, H.P. Fock, T.W. Becker

Photosynthetica 1998, 36(1):107-116 | DOI: 10.1023/A:1007074921833

Air-grown tobacco (Nicotiana tabacum L.) plants were transferred for one week into a low oxygen atmosphere (2 kPa O₂, LO) to study both immediate and long-term effects of the suppression of photorespiration on net photosynthetic rate (P_N), plant morphology, and chloroplast ultrastructure. The P_N and the leaf conductance for CO₂ increased upon exposure of attached tobacco leaves to LO. These results may suggest that under LO, external CO₂ is used to consume the radiant energy normally utilized in photorespiration by net CO₂ assimilation at the expense of an increased rate of transpiration....

Chloroplast biogenesis 80. Proposal of a unified multibranched chlorophyll a/b biosynthetic pathway

C.A. Rebeiz, I.M. Ioannides, V. Kolossov, K.J. Kopetz

Photosynthetica 1998, 36(1):117 | DOI: 10.1023/A:1007027005903

A unified multibranched chlorophyll (Chl) biosynthetic pathway is proposed. The proposed pathway takes into account the following considerations: (a) that the earliest putative precursor of monovinyl Chl b that has been detected in higher plants is monovinyl protochlorophyllide b, (b) that in most cases, Chl b biosynthesis has its roots in the Chl a biosynthetic pathway, (c) that the Chl a biosynthetic pathway exhibits extensive biosynthetic heterogeneity, (d) that Chl biosynthesis may proceed differently at different stages of greening and in different greening groups of plants. Integration of the Chl a and b biosynthetic pathways into a unified multibranched...

Net photosynthetic rate in peanut (Arachis hypogaea L.): Influence of leaf position, time of day, and reproductive-sink

P.C. Nautiyal, V. Ravindra, Y.C. Joshi

Photosynthetica 1998, 36(1):129 | DOI: 10.1023/A:1007079022742

Net photosynthetic rate (P_N) was studied in field-grown peanut cv. GG 2 in relation to leaf position, time of day, reproductive-sink, and phenophase. In general, P_N remained higher in the upper leaves (first from top to the fourth) than in the lower leaves (fifth to eighth). The mean P_N of the leaves situated upper and the leaves lower in the canopy increased from the morning, reached a maximum during noon hours, and decreased thereafter. Between 09:00 to 10:00 h, P_N, stomatal conductance (g_s), and transpiration rate (E) in the upper leaves were higher than in the lower leaves, but between 12:00...

The Influence of Leaf "Windows" on Crassulacean Acid Metabolism in the South African Succulent Senecio Rowleyanus (Asteraceae)

K.J. Egbert, C.E. Martin

Photosynthetica 1998, 36(1):139-147 | DOI: 10.1023/A:1007031106812

Net CO₂ exchange rate (P_N) of shoots and diel fluctuations in titratable acidity of leaves of Senecio rowleyanus were measured to determine whether penetration of radiant energy through leaf "windows" (narrow, translucent strips on the leaf epidermis) resulted in increased CAM. Nocturnal P_N and nighttime increases in acidity were compared among plants with windows covered with reflective adhesive tape, transparent adhesive tape (to control for potential effects of the adhesive), and no tape. The windows did not significantly enhance the degree of CAM in S. rowleyanus.

Thermal dissipation during photosynthetic induction and subsequent dark recovery as measured by photoacoustic signals

C. Buschmann

Photosynthetica 1998, 36(1):149-161 | DOI: 10.1023/A:1007083123650

The thermal photoacoustic signal (279 Hz) and the chlorophyll (Chl) fluorescence of radish cotyledons (Raphanus sativus L.) were measured simultaneously. The signals were recorded during a photosynthetic induction with actinic radiation of different quantum fluence rates [20, 200, and 1200 µmol(PAR-quantum) m^-2 s^-1]. The rise of these signals upon irradiation saturating photosynthesis was followed in the steady state of the induction and during the subsequent dark-recovery (i.e., in dark periods of 1, 5, 15, and 45 min after the induction). From these values various parameters (e.g., quantum yield, photochemical loss, different...

Phycobilisome from Anabaena Variabilis Kütz. and its Model Conjugates

Jiquan Zhao, Jingquan Zhao, Jingmin Zhang, Lijin Jiang

Photosynthetica 1998, 36(1):163-170 | DOI: 10.1023/A:1007035207721

The model conjugates phycocyanin-allophycocyanin (C-PC-APC) and phycoerythrocyanin-phycocyanin-allophycocyanin (PEC-C-PC-APC) were synthesized by using a heterobifunctional coupling reagent N-succinimidyl-3-(2-pyridyldithio)propionate. The rod-core complex (αβ)₆ ^PCL_RC ²⁷(αβ)₃ ^APCL_C ^8.9 and phycobilisomes were separated from Anabaena variabilis. Energy transfer features for the conjugates and the complexes were compared. The absorption and fluorescence emission spectra indicated that the linker-peptides mediate interaction of phycobiliproteins...

Glutathione counteracts the inhibitory effect induced by cadmium on photosynthetic process in soybean

F. El-Shintinawy

Photosynthetica 1998, 36(1):171-179 | DOI: 10.1023/A:1007087224559

In soybean seedlings, Cd²⁺ affected growth and inhibited photosynthesis. Both the length and fresh mass decreased more in roots than in shoots. Cd₂₊ stress caused an increase in ratio of chlorophyll (Chl) (a+b)/b by 1.3 fold and ratio of total xanthophylls/β-carotene by 3 fold compared to the control. A reduced activity of photosystem 2 by about 85 % measured in Cd₂₊-treated chloroplasts was associated with a dramatic quenching of fluorescence emission intensity, with a band shift of 4 nm. A major suppression of absorption was accompanied with shift in peaks in the visible region of the spectrum. In Cd₂₊-treated...

Photosynthetic and stomatal responses of two tropical and two temperate trees to atmospheric humidity

S. Y. Park, A. Furukawa

Photosynthetica 1998, 36(1):181 | DOI: 10.1023/A:1007039308629

The effects of leaf to air vapour pressure differences (ΔW) on net photosynthetic rate (P_N) and stomatal conductance (g_s) were examined in the leaves of two tropical rain forest trees, Eugenia grandis and Pongamia pinnata, and two temperate evergreen trees, Viburnum awabuki and Daphniphyllum macropodum. A single leaf was set inside a small chamber and ΔW was varied from 7 to 24 mmol mol^-1 at 25 and 500 μmol m^-2 s^-1 of photon flux density. P_N and g_s of the two tropical rain forest trees decreased with increasing ΔW, while the two temperate evergreen trees...

Genetically based differences in photochemical activities of isolated maize (Zea mays L.) mesophyll chloroplasts

D. Holá, M. Kočová, M. Körnerová, D. Sofrová, B. Sopko

Photosynthetica 1998, 36(1):187 | DOI: 10.1023/A:1007091325468

Photochemical activity of isolated mesophyll chloroplasts was measured as Hill reaction activity (HRA) and photosystem 1 (PS1) activity in three diallel crosses of maize (Zea mays L.) inbred lines and F₁ hybrids. Statistically significant differences between genotypes together with positive heterotic effect in F₁ generation were found for both traits studied. These differences were more pronounced when HRA or PS1 activity was expressed per leaf area unit or dry matter unit compared to the expression per chlorophyll content unit. Analysis of variance showed that both the genetic and non-genetic components of variation in the photochemical...

Structure-function correlation during the etioplast-chloroplast transition in cucumber cotyledonary leaves

K. Bala Krishna, M.K. Joshi, B. Vani, P. Mohanty

Photosynthetica 1998, 36(1):199-212 | DOI: 10.1023/A:1007043409538

We studied the development of chloroplasts from etioplasts in the cotyledonary leaves of 4-d-old dark-grown cucumber (Cucumis sativus) seedlings after irradiation (20 μmol m^-2 s^-1). Upon irradiation, the triggering of chlorophyll (Chl) synthesis and accumulation showed a relatively short lag phase. The irradiation of etiolated seedlings initiated the synthesis of apoproteins of pigment-protein complexes. While Chl-protein 2 (CP2) was detected at 6 h after irradiation, CP1 only after 29 h. The appearance and accumulation of some of the apoproteins were monitored by Western-blotting. LHC2 apoprotein was detected after a 6 h-irradiation....

Formation of cross-linking between photosystem 2 proteins during irradiation of thylakoid membranes at high temperature

Abhay K. Singh, G.S. Singhal

Photosynthetica 1998, 36(1):213-223 | DOI: 10.1023/A:1007095426376

Irradiation of thylakoid membranes at 40 °C resulted in complete inhibition of photosystem (PS) 2 activity measured as 2,6-dichlorophenol indophenol (DCIP) photoreduction either in the absence or presence of 1,5-diphenylcarbazide (DPC). Concomitant with the inactivation of PS2 activity, several thylakoid proteins were lost and high molecular mass cross-linking products appeared that cross-reacted with antibodies against proteins of PS2 but not with antibodies against proteins of other three complexes PS1, ATP synthase, and cytochrome b₆f. Irradiation of thylakoid membranes suspended in buffer of basic pH or high concentration of Tris at...

Tyrosyl Residue at or Near the Active Site of Maize NADP-malic Enzyme

S.R. Rao, B.G. Kamath, A.S. Bhagwat

Photosynthetica 1998, 36(1):225-231 | DOI: 10.1023/A:1007047610446

Incubation of maize NADP-malic enzyme with tetranitromethane (TNM) resulted in a total loss of enzyme activity. The loss of enzyme activity was not observed at pH 6.3 but at pH 8.0. NADP-malic enzyme was inactivated to almost 90 % by incubation with an 80-fold molar excess of TNM for 5 min at 30 °C. The substrate malate or Mg²⁺ alone gave no protection, while NADP provided considerable protection. NADP in the presence of malate and Mg²⁺ totally protected the enzyme activity, suggesting that tyrosine residue may be located at or near the active site of maize NADP-malic enzyme. The spectral analysis of the modified enzyme indicated...

Photorespiration Rate in Spinach Leaves Under Moderate NaCl Stress

C. Di Martino, S. Delfine, A. Alvino, F. Loreto

Photosynthetica 1998, 36(1):233 | DOI: 10.1023/A:1007099627285

We analyzed the effect of NaCl stress on photorespiration of spinach leaves by calculating the rate of carboxylation/oxygenation of ribulose-1,5-bisphosphate carboxylase/oxygenase, and by measuring the content of amino acids produced through photorespiration. After 20 d of NaCl stress the carboxylation rate was reduced while the oxygenation rate was not affected. The contents of serine, glycine, and alanine increased relevantly. The amount of glutamine also increased after 20 d but the amount of glutamate did not. Hence photorespiration may be stimulated under moderate NaCl stress. A relevant electron transport rate was observed under CO₂-free...

Effects of Micropropagation Conditions of Rose Shootlets on Chlorophyll Fluorescence

C. Genoud, A. Coudret, C. Amalric, H. Sallanon

Photosynthetica 1998, 36(1):243-251 | DOI: 10.1023/A:1007051711355

Rosa hybrida plantlets were rooted on solid sucrosed medium (MS) under an irradiance (PPFD) of 45 μmol m_-2 s_-1 or on liquid hydroponic solution (MH) at 100 μmol m_-2 s_-1. Then all plantlets were acclimated without sucrose under 100 μmol m_-2 s_-1 PPFD. After 7 d in rooting stage, the ratio of variable over maximal chlorophyll fluorescence (F_v/F_m) was significantly higher for plants grown in MH than in MS and hence the higher irradiance at this stage of growth had no photoinhibitory effect. The radiant energy was used by the photochemical process and also by...

Chloroplast Biogenesis 82: Development of a Cell-free System Capable of the Net Synthesis of Chlorophyll(ide) b

V. Kolossov, I.M. Ioannides, S. Kulur, C.A. Rebeiz

Photosynthetica 1998, 36(1):253-258 | DOI: 10.1023/A:1007003828193

Recent experimental evidence (see part 80) suggests that the chlorophyll (Chl) b pathway is biosynthetically heterogeneous. The dissection of this biosynthetic heterogeneity requires the availability of a cell-free system capable of the net synthesis of Chl(ide) a and b. The development of such a system is described.

Effects of Inorganic Nitrogen Availability on the Sporophytes of Acrostichum Aureum L.

R.S. Pillai, B. L. Ong

Photosynthetica 1998, 36(1):259 | DOI: 10.1023/A:1007055812264

Plants grown at low irradiance were fertilized with 0, 60, and 600 g m_-3 NH₄NO₃ once every fortnight. Plants treated with high N concentrations showed an increased growth, producing longer and broader fronds with larger areas, and were darker green in colour. Nitrogen also increased the content of chlorophyll (Chl) and carotenoids per leaf area unit. Different N treatments did not affect the photosynthetic efficiency of photosystem 2, as reflected by the high values of Chl fluorescence kinetics F_v/F_m, ranging between 0.81 to 0.84, and F_v/F₀ of 4.30 to 5.10. An increase in...

Are Calcium Ions and Calcium Channels Involved in the Mechanisms of Cu²⁺ Toxicity in Bean Plants? The Influence of Leaf Age

W. Maksymiec, T. Baszyński

Photosynthetica 1998, 36(1):267 | DOI: 10.1023/A:1007007929102

The influence of calcium channel blockers and ionophore on Cu₂₊-induced changes of the photosynthetic activity of runner bean plants (Phaseolus coccineus L.) was investigated. Excess Cu₂₊ was applied to leaves by injection or via the roots to examine a short/local or a long time/systemic effect of this metal, respectively. The changes in fluorescence parameters indicated that the mechanism of toxic action of Cu₂₊ ions on the photosynthetic apparatus was only partially connected with Ca₂₊ or Ca₂₊ channels. In young plants Ca₂₊ diminished especially photochemical and nonphotochemical dissipative...

Photosynthetic Capacity and Carbon Contribution of Leaves and Bracts to Developing Floral Buds in Cotton

Duli Zhao, D.M. Oosterhuis

Photosynthetica 1998, 36(1):279 | DOI: 10.1023/A:1007059930011

During ontogeny of Gossypium hirsutum L. floral buds (squares), increases in area and dry mass (DM) of floral bracts and the subtending sympodial leaf followed a sigmoid growth curve with increasing square age. The maximum growth rates of the bract area and bract DM occurred between 15 and 20 d after square first appearance (3 mm in diameter). Net photosynthetic rate (P_N) of the sympodial leaf at first fruiting branch position of main-stem node 10 reached a maximum when the subtended square developed into a white flower. Floral bracts had much lower P_N and higher dark respiration than the subtending leaf. The amount of ¹⁴CO₂...

Bibliography of Reviews and Methods of Photosynthesis - 81

Z. Šesták, J. Čatský

Photosynthetica 1998, 36(1):291-319 | DOI: 10.1023/A:1007064014081