Application of Photoautotrophic Suspension Cultures in Plant Science

T. Roitsch, A.K. Sinha

Photosynthetica 2002, 40(4):481-492 | DOI: 10.1023/A:1024332430494

Whereas most plant suspension cultures are grown heterotrophically in the presence of sugars, a limited number of photoautotrophic cultures have been established which are able to grow with CO₂ as the sole carbon source. Photoautotrophic cultures are useful to address various aspects of photosynthesis, source-sink regulation, nitrogen metabolism, production of secondary metabolites, and defence responses. The homogenous populations of these cultures provide an ideal and sensitive system to obtain reproducible results. The availability of an increasing number of photoautotrophic cultures from different economically important species provides...

Photosynthetic Activity and Cellular Integrity of the Andean Legume Pachyrhizus ahipa (Wedd.) Parodi under Heat and Water Stress

M.C. Matos, P.S. Campos, J.C. Ramalho, M.C. Medeira, M.I. Maia, J.M. Semedo, N.M. Marques, A. Matos

Photosynthetica 2002, 40(4):493-501 | DOI: 10.1023/A:1024331414564

Pachyrhizus ahipa (Wedd.) Parodi, originally from Latin America, is an agronomy interesting legume crop due to high seed protein content and saccharides-rich tuber root. Its capacity of adaptation to Mediterranean climate, where heat and water stress are frequently associated, is being tested. Two accessions of P. ahipa (AC 102 and AC 524) differing in field production were compared as concerns the effects of water stress and high temperature on photosynthetic performance. Membrane integrity was also evaluated through electrolyte leakage (injury index, I%), lipid composition, and ultrastructure observations. Short-term heat stress (40...

Correlation between Photoinhibition Sensitivity and the Rates and Relative Extents of Xanthophyll Cycle De-epoxidation in Chlorina Mutants of Barley (Hordeum vulgare L.)

Chang-Lian Peng, Jun Duan, Guizhu Lin, A.M. Gilmore

Photosynthetica 2002, 40(4):503-508 | DOI: 10.1023/A:1024383431403

We compared photoinhibition sensitivity to high irradiance (HI) in wild-type barley (wt) and both its chlorina f₁₀₄-nuclear gene mutant, that restricts chlorophyll (Chl) a and Chl b synthesis, and its f₂-nuclear gene mutant, that inhibits all Chl b synthesis. Both F_v/F_m and Φ_PS2 decreased more significantly in f₂ than f₁₀₄ and wt with duration of HI exposure. Chl degraded more rapidly in the f₂ than in either f₁₀₄ or wt. Most sensitivity to photoinhibition was exhibited for f₂,...

A Salt-Tolerant Cultivar of Wheat Maintains Photosynthetic Activity by Suppressing Sodium Uptake

S. Muranaka, K. Shimizu, M. Kato

Photosynthetica 2002, 40(4):505-515 | DOI: 10.1023/A:1024335515473

The effects of NaCl treatment on the photosynthetic machinery in wheat (Triticum aestivum L.) cultivars differing in salt tolerance were investigated by comparison with iso-osmotic PEG treatment. Both cultivars similarly reduced the photosystem 2 (PS2) energy conversion efficiency (Φ_PS2) rapidly when plants were exposed to a 100 mM NaCl solution, though no decline was detected under the iso-osmotic PEG treatment. There was no correlation between the reduction of the leaf relative water content (RWC) and the Φ_PS2 in the two iso-osmotic stress treatments. In contrast, a decline of Φ_PS2 along with the...

Substitutions of the Conserved Thr42 Increased the Roles of the ε-Subunit of Maize CF₁ as CF₁ Inhibitor and Proton Gate

Zhang-Lin Ni, Da-Fu Wang, Jia-Mian Wei

Photosynthetica 2002, 40(4):517-522 | DOI: 10.1023/A:1024387632311

The conserved residue Thr42 of ε-subunit of the chloroplast ATP synthase of maize (Zea mays L.) was substituted with Cys, Arg, and Ile, respectively, through site-directed mutagenesis. The over-expressed and refolded ε-proteins were purified by chromatography on DEAE-cellulose and FPLC on mono-Q column, which were as biologically active (inhibiting Ca²⁺-ATPase activity and blocking proton gate) as the native ε subunit isolated from chloroplasts. The εT42C and εT42R showed higher inhibitory activities on the soluble CF₁(-ε) Ca²⁺-ATPase than the εWT. The εT42I...

Protective Effects of Exogenous Antioxidants and Phenolic Compounds on Photosynthesis of Wheat Leaves under High Irradiance and Oxidative Stress

Hui Jie Zhao, Qi Zou

Photosynthetica 2002, 40(4):523-527 | DOI: 10.1023/A:1024339716382

Infiltration of methyl viologen (MV, source of O₂^-) and Na-diethyldithiocarbamate (DDC, inhibitor of SOD) into wheat leaves resulted in the accumulation of active oxygen species and photo-oxidative damage to photosynthetic apparatus under both moderate and high irradiance. Exogenous antioxidants, ascorbate (ASA) and mannitol, scavenged active oxygen efficiently, protected the photosynthetic system from MV and DDC induced oxidative damage, and maintained high F_v/F_m [maximal photochemical efficiency of photosystem 2 (PS2) while all PS2 reaction centres are open], F_m/F₀ (another expression...

van Kooten, O., Snel, J.F.H. (ed.): Plant Spectrofluorometry: Applications and Basic Research

Z. Šesták

Photosynthetica 2002, 40(4):528 | DOI: 10.1023/A:1024345212264

Effect of Chlorophyll-Protein Complex I Deficiency on the Physiological Character of a Chlamydomonas reinhardtii Mutant

Qing-Xiu Tang, Zhang-Lin Ni, Jia-Mian Wei

Photosynthetica 2002, 40(4):529-534 | DOI: 10.1023/A:1024391700452

In the mutant CC-1047 of Chlamydomonas reinhardtii, LDS-PAGE showed that the chlorophyll-protein complex I (CPI) is almost absent. The mutant could not grow in a culture medium without organic carbon source while the wild type (WT) C. reinhardtii grew quickly. When an organic carbon source was added into the culture medium, the mutant grew almost as well as WT. The rate of photosystem 1 (PS1) electron transport (DCPIP→MV) and the rate of whole chain electron transport (H₂O→MV) of chloroplasts of the CC-1047 mutant were both lower than those of WT. The photophosphorylation activity, photosynthetic O₂ evolution...

Gas Exchange, Membrane Permeability, and Ion Uptake in Two Species of Indian Jujube Differing in Salt Tolerance

N.K. Gupta, S.K. Meena, S. Gupta, S.K. Khandelwal

Photosynthetica 2002, 40(4):535-539 | DOI: 10.1023/A:1024343817290

Effect of NaCl (electrical conductivity of 0, 5, 10, 15, and 20 dS m^-1) on growth, gas exchange, and ion uptake in two Ziziphus species (Z. rotundifolia and Z. nummularia) differing in salt tolerance was studied. At 30 and 45 d after first leaf initiation, the dry mass of shoot and leaves, and rates of net photosynthesis (P_N) and transpiration (E) decreased significantly with increasing NaCl concentration whereas membrane injury and accumulation of proline increased. The sodium content was highest in the roots of Z. rotundifolia and in the leaves of Z. nummularia. Potassium content...

Mechanism of Action of Sulcotrione, a 4-Hydroxyphenylpyruvate Dioxygenase Inhibitor, in Developed Plant Tissues

J. S. Kim, T. J. Kim, O.K. Kwon, K.Y. Cho

Photosynthetica 2002, 40(4):541-545 | DOI: 10.1023/A:1024395801360

The herbicides diuron, fluridone, or sulcotrione differently reduced chlorophyll (Chl) and carotenoid (Car) contents. Four days after herbicide treatment, application of sulcotrione resulted in a Chl/Car ratio of 5.88, similar as in untreated controls; diuron resulted in ratio of 5.24, while fluridone induced a greater diminution in Car contents and yielded a final ratio of 7.02. Sulcotrione induced a more rapid decrease than fluridone did in the quantum yield of photosystem 2 (PS2) as monitored by Chl fluorescence. Measurements of DPIP reduction with isolated thylakoids indicated that sulcotrione was a more effective inhibitor of the Hill reaction...

Pessarakli, M.: Handbook of Plant and Crop Stresses. 2^nd Ed.

Z. Šesták

Photosynthetica 2002, 40(4):546 | DOI: 10.1023/A:1024393128193

Changes of Photosynthetic Characteristics in Relation to Leaf Senescence in Two Maize Hybrids with Different Senescent Appearance

Ping He, Mitsuru Osaki, Masako Takebe, Takuro Shinano

Photosynthetica 2002, 40(4):547-552 | DOI: 10.1023/A:1024347918199

A field experiment was conducted to investigate the changes in chlorophyll (Chl) and nitrogen (N) contents, ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBPCO) and phosphoenolpyruvate carboxylase (PEPC) contents and PEPC activity, and the photon-saturated net photosynthetic rate (P_Nsat), and their relationships with leaf senescence in two maize hybrids with different senescent appearance. One stay-green (cv. P3845) and one earlier senescent (cv. Hokkou 55) hybrid were used in this study, and we found that Chl and N contents and the P_Nsat in individual leaves of P3845 were greater than those in corresponding...

Stomatal and Mesophyll Limitations to Photosynthesis in One Evergreen and One Deciduous Mediterranean Oak Species

S. Mediavilla, H. Santiago, A. Escudero

Photosynthetica 2002, 40(4):553-559 | DOI: 10.1023/A:1024399919107

In the evergreen Quercus rotundifolia and the co-existing deciduous Q. faginea we studied the diurnal variations in photosynthetic capacity (P_max), measured as the rate of O₂ evolution at photon and CO₂ saturation, and in the rate of net CO₂ assimilation (P_N) in the field during the period of maximum photosynthetic activity. Our aim was to check the contribution of stomatal and non-stomatal limitations to the diurnal variation in photosynthesis, and to study the differences between both species. Q. faginea leaves displayed lower mass per unit area and higher nitrogen...

Chen, F., Jiang, Y. (ed.): Algae and Their Biotechnological Potential.

J. Kopecký

Photosynthetica 2002, 40(4):560 | DOI: 10.1023/A:1024341111355

Ribulose-1,5-Bisphosphate Carboxylase/Oxygenase Specific Proteolysis in Barley Chloroplasts During Dark Induced Senescence

L. Simova-Stoilova, K. Demirevska-Kepova, Z. Stoyanova

Photosynthetica 2002, 40(4):561-566 | DOI: 10.1023/A:1024304103178

Intact chloroplasts were isolated from dark-senescing primary barley (Hordeum vulgare L.) leaves in order to study selective ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBPCO) degradation by the stromal and membrane fractions. RuBPCO specific degradation was estimated and characterised applying sensitive avidin-biotin ELISA method with non-modified or oxidatively modified biotinylated RuBPCO (BR) as substrates. Distinct proteolytic activities were detected. They differed in ATP and divalent metal ion dependence, protease inhibitory profile, and dynamics in the time-course of dark-induced senescence. The results supported involvement of...

Treatment with Methyl Jasmonate Alleviates the Effects of Paraquat on Photosynthesis in Barley Plants

V.A. Hristova, L.P. Popova

Photosynthetica 2002, 40(4):567-574 | DOI: 10.1023/A:1024356120016

Twelve-day-old barley seedlings were supplied with 23 μM methyl jasmonate (MeJA) or 10 μM paraquat (Pq) via the transpiration stream and kept in the dark for 24 h. Then they were exposed to 100 μmol m^-2 s^-1 PAR and samples were taken 1, 2, 3, and 6 h after irradiation. Treatment of seedlings with MeJA alone resulted in decreased content of chlorophyll (Chl), and net photosynthetic (P_N) and transpiration rates. Pq treatment led to a decrease in Chl content and to a very strong inhibition of P_N, the effects were manifested by 1 h of irradiation. Pq treatment did not affect the...

Photosynthesis of Cockspur [Echinochloa crus-galli (L.) Beauv.] at Sites of Naturally Elevated CO₂ Concentration

D. Vodnik, H. Pfanz, I. Maček, D. Kastelec, S. Lojen, F. Batič

Photosynthetica 2002, 40(4):575-579 | DOI: 10.1023/A:1024308204086

High abundance of cockspur (Echinochloa crus-galli) at the geothermal carbon dioxide spring area in Stavešinci indicates that this species is able to grow under widely varying CO₂ concentrations. Living cockspur plants can even be found very close to gas-releasing vents where growth is significantly reduced. Plant height correlated well with CO₂ exposure. The δ¹³C value of the CO₂ spring air was -3.9 ‰ and δ¹³C values of high-, medium-, and low-CO₂ plants were -10.14, -10.44, and -11.95 ‰, respectively. Stomatal response directly followed the prevailing...

Wilson, K, Walker, J.: Principles and Techniques of Practical Biochemistry. 5^th Ed.

N. Wilhelmová

Photosynthetica 2002, 40(4):580 | DOI: 10.1023/A:1024380827285

Effects of High Temperature on Chlorophyll Fluorescence Induction and the Kinetics of Far Red Radiation-Induced relaxation of apparent F₀ in maize leaves

Ming-Xian Jin, De-Yao Li, Hualing Mi

Photosynthetica 2002, 40(4):581-586 | DOI: 10.1023/A:1024360220925

Temperature dependence (25-50 °C) of chlorophyll (Chl) fluorescence induction, far-red radiation (FR)-induced relaxation of the post-irradiation transient increase in apparent F₀, and the trans-thylakoid proton gradients (ΔpH) was examined in maize leaves. Temperatures above 30 °C caused an elevation of F₀ level and an enhancement of F₀ quenching during actinic irradiation. Millisecond delayed light emission (ms-DLE), which reflects the magnitude of ΔpH, decreased strikingly above 35 °C, and almost disappeared at 50 °C. It indicates that the heat-enhanced quenching of F₀ under actinic irradiation...

Thermotolerance of Photosystem 2 of Three Alpine Plant Species Under Field Conditions

V. Braun, O. Buchner, G. Neuner

Photosynthetica 2002, 40(4):587-595 | DOI: 10.1023/A:1024312304995

The species specific response of photosystem 2 (PS2) efficiency and its thermotolerance to diurnal and seasonal alterations in leaf temperature, irradiance, and water relations were investigated under alpine field conditions (1 950 m) and in response to an in situ long-term heat treatment (+3 K). Three plant species were compared using the naturally occurring microstratification of alpine environments, i.e. under contrasting leaf temperatures but under similar macroclimatic conditions. Thermotolerance of PS2 showed a high variability in all three species of up to 9.6 K. Diumal changes (increases or even decreases) in PS2 thermotolerance...

Photoinhibition of Photosynthesis in Vitis berlandieri and Vitis rupestris Leaves under Field Conditions

M. Bertamini, N. Nedunchezhian

Photosynthetica 2002, 40(4):597-603 | DOI: 10.1023/A:1024364321833

Photoinhibition of photosynthesis was investigated in Vitis berlandieri and Vitis rupestris leaves under field conditions at different sampling time in a day. The degree of photoinhibition was determined by means of the ratio of variable to maximum chlorophyll fluorescence (F_v/F_m) and photosynthetic electron transport measurements. When the photochemical efficiency of PS2, F_v/F_m, markedly declined, F₀ increased significantly in leaves of V. berlandieri, while F₀ did not increase in V. rupestris leaves. Isolated thylakoids of leaves of V. berlandieri...

Responses of Tobacco Plantlets to Change of Irradiance During Transfer from in vitro to ex vitro Conditions

Š. Semorádová, H. Synková, J. Pospíšilová

Photosynthetica 2002, 40(4):605-614 | DOI: 10.1023/A:1024316405903

Chlorophyll a fluorescence kinetics, net photosynthetic rate (P_N), water relations, and photosynthetic pigment contents were studied during acclimation of in vitro grown tobacco to higher irradiance (HL; 700 μmol m^-2 s^-1). Plantlets were grown on medium containing sucrose in glass vessels (G-plants) or in Magenta boxes (M-plants) with better CO₂ supply in the latter ones. The effect of HL was studied either (1) in plantlets grown under original in vitro conditions (closed vessels), (2) in in vitro plantlets exposed to ambient CO₂ concentration...

Gas Exchange Characteristics and Water Relations in Some Elite Okra Cultivars Under Water Deficit

M. Ashraf, M. Arfan, M. Shahbaz, Ashfaq Ahmad, A. Jamil

Photosynthetica 2002, 40(4):615-620 | DOI: 10.1023/A:1024368522742

Thirty-days-old plants of two cultivars of okra (Hibiscus esculentus L.), Sabzpari and Chinese-red, were subjected for 30 d to two water regimes (100 and 60 % field capacity). Leaf water potential and osmotic potential of both lines decreased significantly with the imposition of drought. Both the leaf pressure potential and osmotic adjustment were much lower in Chinese-red than those in Sabzpari. Chlorophyll (Chl) b content increased, whereas Chl a content remained unchanged and thus Chl a/b ratios were reduced in both lines. Drought stress also caused a significant reduction in net photosynthetic rate (P_N),...

Effect of Foliar Application of Chitin and Chitosan Oligosaccharides on Photosynthesis of Maize and Soybean

W.M. Khan, B. Prithiviraj, D.L. Smith

Photosynthetica 2002, 40(4):621-624 | DOI: 10.1023/A:1024320606812

On the first day after foliar application, chitosan pentamer (CH5) and chitin pentamer (CHIT5) decreased net photosynthetic rate (P_N) of soybean and maize, however, on subsequent days there was an increase in P_N in some treatments. CH5 caused an increase in maize P_N on day 3 at 10^-5 and 10^-7 M; the increases were 18 and 10 % over the control plants. This increase was correlated with increases in stomatal conductance (g_s) and transpiration rate (E), while the intercellular CO₂ concentration (C_i) was not different from the...

Photosynthetic Response to Irradiance in Valeriana jatamansi Jones, a Threatened Understorey Medicinal Herb of Western Himalaya

S.K. Vats, S. Pandey, P.K. Nagar

Photosynthetica 2002, 40(4):625-628 | DOI: 10.1023/A:1024372623650

Net photosynthetic rate (P_N) of Valeriana jatamansi plants, grown under nylon net shade or under different tree canopies, was saturated with photons at 1 000 μmol m^-2 s^-1 photosynthetic photon-flux-density (PPFD), whereas open-grown plants were able to photosynthesise even at higher PPFD, e.g. of 2 000 μmol m^-2 s^-1. Plants grown under net shade had higher total chlorophyll (Chl) content per unit area of leaf surface. However, Chl a/b ratio was maximal in open-grown plants, but remained unchanged in plants grown in nylon net shade and under different tree canopies....

Irradiance Effects on Growth and Bacteriochlorophyll Content of Phototrophic Heliobacteria, Purple and Green Photosynthetic Bacteria

L.K. Kimble-Long, M.T. Madigan

Photosynthetica 2002, 40(4):629-632 | DOI: 10.1023/A:1024324707721

Two species of heliobacteria along with a purple and green bacterium were tested for their ability to grow phototrophically at irradiances ranging from 0.125 to 50 W m^-2. The heliobacteria were incapable of growth below 0.5 W m^-2, while both the purple and green bacterium grew at significantly lower irradiances. Specific bacteriochlorophyll contents were higher for the purple and green bacteria than for the heliobacteria at all irradiances tested. Thus in distinct contrast to purple and green bacteria, heliobacteria are "high-irradiance" phototrophs, and this characteristic may influence their distribution in nature.

Activities of Carbonic Anhydrase and Ribulose-1,5-Bisphosphate Carboxylase, and Dry Mass Accumulation in Brassica juncea following Defoliation

N.A. Khan

Photosynthetica 2002, 40(4):633-634 | DOI: 10.1023/A:1024376724559

The effect of 30 % defoliation of shaded leaves in lower layers of plant was studied on activities of carbonic anhydrase (CA) and ribulose-1,5-bisphosphate carboxylase (RuBPC), leaf dry mass per unit leaf area, and plant dry mass of mustard (Brassica juncea). Removal of 30 % of leaves resulted in increased CA and RuBPC activities of leaves, and leaf and plant dry masses.

The Effect of Phyllode Temperature on Gas Exchange and Chlorophyll Fluorescence of Acacia mangium

Hua Yu, Bee-Lian Ong

Photosynthetica 2002, 40(4):635-639 | DOI: 10.1023/A:1024328808629

The optimum temperature for photosynthetic CO₂ assimilation of A. mangium phyllodes was 30-32 °C. Photosystem 2 (PS 2) exhibited high tolerance to high temperature. Gas exchange and the function of PS2 of A. mangium were adapted to the temperature regime of the tropical environment and this might be the contributing factor to their fast growth under tropical conditions.