The Development of Chloroplast Structure During Leaf Ontogeny

J. Kutík

Photosynthetica 1997, 35(4):481-505 | DOI: 10.1023/A:1006940421476

Advances achieved during last fifteen years in the understanding the development of chloroplast ultrastructure during natural leaf ontogeny are summarized. Life span of a typical C3 mesophyll cell chloroplast is outlined and placed into the scheme of cyclic plastid interrelationships. Possible modifications of this development by stresses, environmental factors or experimental treatments are also shown.

van den Hoek, C., Mann, D.G., Jahns, H.M.(ed.): Algae. An Introduction to Phycology

V. Zachleder

Photosynthetica 1997, 35(4):506 | DOI: 10.1023/A:1006955729654

Photosynthetic Performance and Water Use Efficiency of the Fern Cheilanthes Persica

L. Gratani, M.F. Crescente, G. Rossi

Photosynthetica 1997, 35(4):507-516 | DOI: 10.1023/A:1006970705546

Morphological, anatomical and physiological frond traits of Cheilanthes persica (Bory) Mett. ex Kuhn were studied to analyze its adaptive strategy. Mean frond life span is about 340 d. Mature fronds are characterized by 91 g m-2 areal dry mass (ADM) and 217 g m-2 succulence. The reduction of frond water content in July (dehydration phase) caused a 51 % decrease in frond surface area (SA). Fronds were dry in August (desiccation phase); nevertheless, in September they showed an increased SA (rehydration phase). Chlorophyll (Chl) a/b ratio, above 3, and the well developed palisade parenchyma (two layers, total thickness of 103.9 µm) are typical...

Diurnal and Seasonal Changes in Prunus Amygdalus Gas Exchanges

M.C. Matos, A.A. Matos, A. Mantas, V. Cordeiro, J.B. Vieira Da Silva

Photosynthetica 1997, 35(4):517-524 | DOI: 10.1023/A:1006922822385

Diurnal courses in net photosynthetic rate (PN), stomatal conductance (gs), leaf water potential (ψ), internal CO2 concentration (ci), and water use efficiency (WUE) were studied as season progressed, in relation to environmental factors in field grown Prunus amygdalus. In sun leaves PN reached maximum between 09:00 to 11:00 h and subsequently declined when high temperature and low humidity occurred. An increase was observed late in the afternoon. A decrease in gs and ψ was found as season progressed in both years of measurements. In periods of high evaporative demand, ψ was very low, however, it did not explain the reductions of PN in...

Photosynthesis-Nitrogen Relationships in Pioneer Plants of Disturbed Tropical Montane Forest Sites

A. Quilici, E. Medina

Photosynthetica 1997, 35(4):525-534 | DOI: 10.1023/A:1006974806455

Tropical forest disturbances lead to the establishment of secondary successional plant communities constituted by light demanding species with high relative growth rate that conduct to rapid canopy closure. Two main strategies for N nutrition are: (a) mineral N acquisition in the form of NH4 and NO3, and (b) symbiotic atmospheric N2 fixation. Given the high N requirement for maximization of leaf area and radiant energy absorption, we hypothesize that contrasting strategies of N nutrition in these environments are reflected in leaf photosynthetic characteristics. We compared the N-photosynthesis relationships and carbon balance parameters per unit leaf...

Diurnal and Seasonal Variations in Chlorophyll a Fluorescence in Two Mediterranean-Grassland Species Under Field Conditions

L. Fernández-Baco, M.E. Figueroa, T. Luque, A.J. Davy

Photosynthetica 1997, 35(4):535-544 | DOI: 10.1023/A:1006926923293

Seasonal and daily variations in chlorophyll (Chl) fluorescence were studied in two representative species of Mediterranean grasslands, Tuberaria guttata (an annual) and Chamaemelum nobile (a perennial), in order to assess physiological responses to climatically induced stresses during the growing season. The photochemical efficiency of photosystem (PS) 2 in dark-adapted leaves was measured by the Chl fluorescence ratio Fv/Fp. This ratio decreased progressively from December to July, as the effects of increasing solar radiation and summer drought became more severe. The seasonal decline was observed particularly as a depression of morning and midday...

Influence of the Degree of Solvent Impurity on the Spectrophotometric Determination of Chlorophylls in 80 % Aqueous Acetone and Dimethyl formamide. Application to Non-Abrasive Extraction of Leaves of Citrus Aurantium

A.L. García, N. Nicolás

Photosynthetica 1997, 35(4):545-550 | DOI: 10.1023/A:1006978907364

Chlorophyll (Chl) a and Chl b absorbances were determined in extracts from leaves of Citrus aurantium L. using the solvents diethyl ether (100 %), buffered 80 % aqueous acetone, and N,N'-dimethyl formamide (DMF) (99.83 %). The respective standard deviations (σ) and coefficients of variability (CV) were used to establish the errors obtained when using impure solvents. Buffered 80 % aqueous acetone gave an error of 2.1 % for Chl a and 7.1 % for Chl b, while DMF gave errors of 3.5 and 6.7 %, respectively. For current Chl determination we propose a non-abrasive method, which extracts 15 leaf discs (diameter 6 mm) with 10 cm3 of buffered 80 % aqueous...

Action of Mercury on the Photosynthetic Apparatus of Spinach Chloroplasts

F. Šeršeň, K. Kráľová, A. Bumbálová

Photosynthetica 1997, 35(4):551-559 | DOI: 10.1023/A:1006931024202

In chloroplasts of Spinacea oleracea L., Hg2+ ions interact with some sites in the photosynthetic electron transport chain: (l) with the intermediates Z+/D+ situated in the D1 and D2 proteins and with the manganese cluster in the oxygen evolving complex which are located on the donor side of photosystem (PS) 2, (2) with the chlorophyll a dimer in the core of PS1 (P700). P700 is oxidized in the dark by HgCl2. The Hg2+ ions form organometallic complexes with amino acids contained in chloroplast proteins.

Dashek, W.V. (ed.): Methods in Plant Biochemistry and Molecular Biology

D. Sofrová

Photosynthetica 1997, 35(4):560 | DOI: 10.1023/A:1006903712815

Chloroplastic Carbon Dioxide Concentration in Norway Spruce (Picea Abies [L.] Karst.) needles relates to the position within the crown

T. Priwitzer, O. Urban, M. Šprtová, M.V. Marek

Photosynthetica 1997, 35(4):561-571 | DOI: 10.1023/A:1006983008272

Differences between sun (E) and shaded (S) foliage were studied in a Norway spruce (Picea abies [L.] Karst.) stand. Response curves describing the dependence of the CO2 assimilation rate (PN) on the CO2 concentration at the catalytic site of ribulose-1,5-bisphosphate carboxylase/oxygenase, RuBPCO (PN-Cc) were estimated using the simultaneous measurements of chlorophyll fluorescence and leaf gas exchange. Higher PN, higher electron transport (Ja), higher carboxylation capacity (Vc), and higher RuBPCO activity (τ) for sun acclimated needles was found. The S-needles had higher portion of internal limitation and higher CO2 compensation concentration...

Photosynthetic and Transpiration Rates of Soybean as Affected by Different Irradiances During Growth

Y. Koesmaryono, H. Sugimoto, D. Ito, T. Haseba, T. Sato

Photosynthetica 1997, 35(4):573-578 | DOI: 10.1023/A:1006935125111

The diurnal variation of net photosynthetic (PN) and transpiration (E) rates in soybean [Glycine max (L.) Merr. cv. Fukuyutaka] plants grown under 100, 50, or 25 % of full sun irradiance (I100, I50, I25 plants) were compared. In the morning, activities of the plants were measured at irradiances under which they grew. However, during the afternoon, all the plants were tested under full irradiance. The lower the growth irradiance, the lower PN, E, and mesophyll conductance values were found. Stomatal conductance was considerably lower in I25 plants only. Both the increase in specific leaf area (SLA) and the decrease in nitrogen content per leaf area...

Gas Exchange in Senescing Leaves of Olea Europaea L.

P. Proietti

Photosynthetica 1997, 35(4):579-587 | DOI: 10.1023/A:1006987109181

From the beginning of olive leaf yellowing to leaf fall (1/3 months), there was a general trend from anabolism to catabolism. Rates of net photosynthesis (PN) and respiration, areal dry mass, and contents of pigments, particularly of chlorophyll (Chl) a, starch, and above all nitrogen (N) decreased. The detachment force decreased dramatically only in completely chlorotic leaves. Chl a : b ratio only declined in the last 10-20 d of senescence, when the total Chl contents diminished by about 70 %, after which the N content, PN, and efficiency of the photochemical energy conversion of the remaining Chl and N dramatically declined. Consequently, for most...

Effects of Exposure in Space on Tomato Seeds: Photosynthesis, Biomass, and Water Relations of Well-Watered and Drought-Stressed Plants

M.S. Marmor, C.E. Martin

Photosynthetica 1997, 35(4):589-596 | DOI: 10.1023/A:1006939226019

Tomato seeds exposed to space conditions for nearly six years on board the Long Duration Exposure Facility (LDEF) satellite were subsequently germinated and the resultant seedlings grown on earth under controlled conditions for analysis. Photosynthesis, biomass, and water relations were compared between mature plants grown from earth-based control seeds and space-exposed seeds under both well-watered and drought-stressed conditions. No consistent significant differences in photosynthesis and water relations were observed in the two sets of plants at any level of drought stress. Fruit production, however, though limited and variable, was significantly...

Effects of Elevated CO2 and Moisture Stress on Brassica Juncea

B.K. Rabha, D.C. Uprety

Photosynthetica 1997, 35(4):597-602 | DOI: 10.1023/A:1006991210089

The interactive effect of elevated CO2 (EC) and moisture stress (MS) on Brassica juncea cv. Pusa Bold was studied using open-top chambers. The EC markedly increased net photosynthetic rate and internal CO2 concentration and reduced variable and maximal chlorophyll fluorescence. Under MS, EC increased water potential and relative water content, and reduced transpiration rate. The greater allocation of biomass to the roots, which serve as a strong sink for assimilated carbon under EC, helped in better root growth.

The Activity and Content of Ribulose-1,5-Bisphosphate Carboxylase/Oxygenase in Wheat Plants as Affected by Water Stress and Kartolin-4

I.I. Chernyad'ev, O.F. Monakhova

Photosynthetica 1997, 35(4):603-610 | DOI: 10.1023/A:1006943326928

The carboxylating activity and content of ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBPCO, EC 4.1.1.39), and other soluble proteins in young seedlings and mature leaves of Lutescens-758, a drought-sensitive cultivar of soft spring wheat Triticum aestivum L., were studied under the conditions of drought and subsequent rehydration. Seedlings and mature plants preliminarily treated with the cytokinin-like compound kartolin-4 were compared to untreated plants. Drought-induced decrease in RuBPCO activity should be attributed not only to proteolytic decomposition of the enzyme protein itself but also to a partial inhibition of its catalytic activity....

Analysis of Photosynthetic Responses and Adaptation to Nitrogen Starvation in Chlorella Using In Vivo Chlorophyll Fluorescence

O.H. Sayed

Photosynthetica 1997, 35(4):611-619 | DOI: 10.1023/A:1006995410998

Nitrogen (N) starvation resulted in degreening, inhibition of photosynthetic oxygen evolution and dark respiration, reduced survival, and increased age-specific mortality in both Chlorella fusca and Chlorella vulgaris. Analysis of in vivo chlorophyll (Chl) fluorescence induction kinetics revealed the presence of N-starvation-induced changes at the level of degreened thylakoids in both species. These changes included decreased yield of the photochemistry of photosystem 2 (PS2), and a declined photosynthetic efficiency. Synthesis of secondary carotenoids represented a biochemical change in carotenogenesis that had a photoprotective effect in degreened...

Photoprotective Energy Dissipation in Higher Plant Leaves Investigated by Chlorophyll Fluorescence Decay Measurements with Additional Radiation Pulses

F. Terjung

Photosynthetica 1997, 35(4):621-629 | DOI: 10.1023/A:1006947527836

Chlorophyll (Chl) fluorescence decay measurements were performed on higher plant leaves to investigate the photoprotective mechanisms under in vivo conditions. Measurements on leaves with different amounts of zeaxanthin pointed out that zeaxanthin is necessary for most of the observed nonphotochemical energy quenching, that has to be activated by a transthylakoid ΔpH. An additional sustained energy quenching component was clearly resolved in leaves with high amounts of zeaxanthin. The changes of the Chl fluorescence decay parameters did not correlate with a photoprotective energy dissipation in the reaction centre of photosystem 2 (P680), nor...

Relationships Between Nitrogen Content and Net Gas Exchange Components of a Cotton Leaf During Ontogeny

B.R. Bondada, D.M. Oosterhuis

Photosynthetica 1997, 35(4):631-635 | DOI: 10.1023/A:1006999511907

Relationships between leaf nitrogen (N) content and leaf gas exchange components of a single cotton (Gossypium hirsutum L.) leaf subtending the fruit during ontogeny were investigated under field conditions. A 20-d old leaf exhibited the highest physiological activity characterized by net photosynthetic (PN) and transpiration (E) rates, stomatal conductances to CO2 exchange (gsCO2) and water vapor transfer (gsH2O), and nitrogen (N) content. With the advent of leaf senescence, the gas exchange rates declined as exhibited by the 30-, 40-, and 60-d old leaves. Regression analysis indicated close relationships between gsCO2 and PN, and gsH2O and E as the...

Enhanced Water Use Efficiency in Dry Loess Grassland Species Grown at Elevated Air CO2 Concentration

K. Szente, Z. Nagy, Z. Tuba

Photosynthetica 1997, 35(4):637-640 | DOI: 10.1023/A:1006951628745

Net CO2 assimilation rate (PN), stomatal conductance (gs), transpiration rate (E), and water use efficiency (WUE) in four perennial C3 species (grasses: Dactylis glomerata, Festuca rupicola, dicots: Filipendula vulgaris, Salvia nemorosa) grown for 231 d in open-top chambers at ambient (CA, 350 µmol mol-1) or elevated (CE, 700 µmol mol-1) CO2 concentrations were compared. When measured at CE, PN was significantly higher in CE plants of all four species than in the CA ones. The increase in PN was less prominent in the two grasses than in the two dicots. The E was significantly higher in the CE-grass F. rupicola and CE-dicot F. vulgaris than...