Photosynthetica, 1995 (vol. 33), issue 2

Article

Refined carotenoid analysis of the major light-harvesting complex of Mantoniella squamata

C. Wilhelm, S. Kolz, M. Meyer, A. Schmitt, H. Zuber, E.S. Egeland, S. Liaaen-Jensen

Photosynthetica 1995, 33(2):161 | DOI: 10.1023/A:1022191626356

The major light-harvesting complex (LHC) of the prasinophycean alga Mantoniella squamata is unique compared to other chlorophyll (Chl) a/b-binding LHC with respect to the primary protein structure and the pigmentation. Although the presence of Chl a, Chl b, a Chl c-type pigment and the xanthophylls neoxanthin, violaxanthin and prasinoxanthin was clearly determined, several carotenoids remained unidentified or were described controversially. We re-analysed the carotenoid composition and identified a new set of xanthophylls present in the LHC: uriolide, micromonol, micromonal and dihydrolutein. Additionally, one hydrophobic...

Genetic variability in photosynthetic rate and leaf characters in Brassicaceae coenospecies

K. Suresh, K.L.N. Rao, T.V.R. Nair

Photosynthetica 1995, 33(2):173-178 | DOI: 10.1023/A:1022147910426

Thirty-nine Brassica coenospecies grown in pot cultures during 1993 and 1994 were screened for variability in photosynthetic rate (P _N ) and leaf characters. There were significant differences among the species in P _N per unit leaf area, chlorophyll (Chl) content, specific leaf mass (SLM), stomatal resistance (r _s ) and individual leaf size. The interactions species x year and species x date of measurement were small compared to the species effect. There was a significant negative correlation between P _N and r _s...

Short-term feedback inhibition of photosynthesis in wheat leaves supplied with sucrose and glycerol at two temperatures

R. Morcuende, P. Pérez, R. Martínez-Carrasco

Photosynthetica 1995, 33(2):179-188 | DOI: 10.1023/A:1022199927264

The inhibition of photosynthesis by reduced sink demand or low rates of end product synthesis was investigated by supplying detached wheat (Triticum aestivum L. cv. Tauro) leaves with 50 mM sucrose, 50 mM glycerol or water through the transpiration stream for 2 h, either at 23 or 12 °C. Lowering the temperature and sucrose and glycerol feeding decreased photosynthetic oxygen evolution at high irradiance and saturating CO₂. The decrease in temperature reduced the pools of sucrose and starch, and the ratio glucose 6-phosphate (G6P)/fructose 6-phosphate (F6P), while it increased the concentrations of G6P and F6P (hexose phosphates)....

Effects of phosphate on the activity, stability and regulatory properties of phosphoenolpyruvate carboxylase from the C4 plant Cynodon dactylon

G. Salahas, N.A. Gavalas

Photosynthetica 1995, 33(2):189 | DOI: 10.1023/A:1022152028173

The extraction of phosphoenolpyruvate carboxylase, PEPC (EC 4.1.1.31) from leaves of Cynodon dactylon (L.) Pers. with phosphate buffer (pH 7.4, 105 mM) was advantageous in comparison to the usual extraction with Tris-HCl buffer (pH 7.4, 100 mM); a higher activity was obtained, which was most evident at low substrate (phosphoenolpyruvate) concentrations. The PEPC activity was stable under dilution or in storage for at least 48 h at room temperature. The effects of phosphate buffer were not due to inhibition of phosphatase(s) action during the extraction, since they were also observed when the phosphates were added after the extraction with Tris-HCl....

Planting density effects on assimilation and partitioning of photosynthates during grain filling in the late-sown wheat

Zhenlin Wang, Jinmin Fu, Mingrong He, Yanping Yin, Hongming Cao

Photosynthetica 1995, 33(2):199-204 | DOI: 10.1023/A:1022156112243

Leaf blades of the late-sown winter wheat produced the major portion, i.e., more than 60 %, of the total ¹⁴C-photosynthates at grain filling, but ear (rachis and glumes) only about 15 %, sheaths about 11 %, and stem internodes about 11 %. The change of plant density in this experiment had little influence on the ¹⁴CO2-photoassimilation of the ear (rachis and glumes), flag leaf lamina, sheaths and stem internodes, but markedly affected photosynthesis of the second, the third and lower leaves. The photosynthetic rate [expressed as specific radioactivity, s-¹ kg-¹(d.m.)] and the amount of ¹⁴CO₂...

The Moricandia syndrome in species of the Brassicaceae - evolutionary aspects

P. Apel, C. Horstmann, M. Pfeffer

Photosynthetica 1995, 33(2):205-215 | DOI: 10.1023/A:1022108229082

The CO₂ compensation concentration (Γ) and leaf anatomy were determined in 107 species of six tribes of Brassicaceae. There was an abundant bundle-sheath in all investigated species. The Moricandia syndrome, characterized by a high concentration of chloroplasts in the bundle-sheath cells and Γ values < 30 cm₃(CO₂) m-³, was found within species of the genera Moricandia, Diplotaxis and Brassica. Available results from molecular systematics indicate a common phylogenetic ancestor, suggesting monophyletic evolution of the syndrome within the tribe Brassiceae....

Competition between the photosynthetic and the (chloro)respiratory electron transport chains in cyanobacteria, green algae and higher plants. Effect of heat stress

F. Lajkó, A. Kadioglu, G. Borbély, G. Garab

Photosynthetica 1995, 33(2):217-226 | DOI: 10.1023/A:1022160213152

By measuring the effect of cyanide on the flash-induced redox reactions of the cytochrome (cyt) b ₆/f complex we carried out a comparative study in order to characterize the interaction between the photosynthetic and the respiratory electron transport systems in cyanobacterial (Synechococcus sp. PCC 6301) and green algal (Chlamydomonas reinhardtii) cells, and in tobacco (Nicotiana tabacum L. cv. Petit Havana SR1) protoplasts. We found that the addition of 1 mM KCN resulted in a significant acceleration of the rereduction-rate of cyt f ⁺. This enhancement of the activity of the cyt b...

Occurrence and ecological characteristics of C4 dicot and Cyperaceae species in the Hungarian flora

T. Kalapos, A. Baloghné-Nyakas, P. Csontos

Photosynthetica 1995, 33(2):227-240 | DOI: 10.1023/A:1022112329990

The non-graminaceous wild flora of Hungary was screened for C₄ plants by using the stable carbon isotope ratio, the leaf anatomy and the photosynthetic carbon dioxide compensation concentration to determine the photosynthetic pathway type. On the whole, 31 C₄ species (native or naturalized) were found in the Amaranthaceae, Chenopodiaceae, Cyperaceae, Euphorbiaceae, Portulacaceae and Zygophyllaceae families. Together with the 26 C₄ grass species (Poaceae) reported earlier (Kalapos 1991), a total of 57 wild C₄ species occur in Hungary, which forms 2.6 % of the country's angiosperm flora. This...

Photosynthesis and growth of Erythrina variegata as affected by water stress and triacontanol

K. Muthuchelian, C. Murugan, N. Nedunchezhian, G. Kulandaivelu

Photosynthetica 1995, 33(2):241-248 | DOI: 10.1023/A:1022164314060

Erythrina variegata Lam. seedlings were grown under water stress (Ψ = -3.2 MPa) and subsequently sprayed with triacontanol (Tria). Water stress significantly reduced shoot growth rate, while roots continued to grow. Content of chlorophyll (Chl) a decreased more than that of Chl b. Water stress also reduced photosynthetic activity of chloroplasts as measured by Chl fluorescence induction. Stress effect was identified at the oxidation site of photosystem (PS) 2 prior to the hydroxylamine donating site and perhaps close to or after the diphenylcarbazide donating site. The loss of O₂ evolving thylakoid polypeptides (33,...

Photosynthesis and yield performance of cassava in seasonally dry and semiarid environments

S.M. De Tafur, M.A. El-Sharkawy, F. Calle

Photosynthetica 1995, 33(2):249-257 | DOI: 10.1023/A:1022116414969

Two field trials with two groups of cassava (Manihot esculenta Crantz) cultivars were conducted under rainfed conditions in seasonally dry and semiarid environments at the northern coast of Colombia, South America, to evaluate the genetic diversity in photosynthesis and productivity, and to determine their interrelationship. There were significant differences among cultivars in both environments, in average net photosynthetic rates (P _N ) of upper canopy leaves and in final dry root yields. Both P _N and dry root yields were much higher in the seasonally dry environment than in the semiarid...

The photosynthetic irradiance-response of Norway spruce exposed to a long-term elevation of CO₂ concentration

M.V. Marek, M. Sprtová, J. Kalina

Photosynthetica 1995, 33(2):259 | DOI: 10.1023/A:1022120531807

During an open-top chamber experiment performed in a mountain stand of young (12-year-old) Norway spruce (Picea abies [L.] Karst.), the trees were exposed to one of two CO² concentrations (ambient CO², AC, or AC + 350 µmol mol-1 = elevated CO₂, EC) continuously over three growing seasons. To evaluate the EC influence, measurements of the relations between the rate of net CO₂ uptake (P _N ) and incidental photosynthetically active photon flux density (PPFD), as well as the content of photosynthetic pigments and chlorophyll (Chl) a fluorescence were taken in the third growing...

Effect of fruiting and drought or flooding on carbon balance of apple trees

M.L. Wibbe, M.M. Blanke

Photosynthetica 1995, 33(2):269 | DOI: 10.1023/A:1022172515878

The response of fruiting or deblossomed trees to water stress such as drought or flooding was investigated in six semi open-top cuvettes each containing one apple (Malus domestica Borkh. cv. Golden Delicious) tree. Xylem water potentials of leaves dropped from -1.2 to -4.1 MPa within 7 d of drought, the effect being enhanced by fruiting. Apple trees without fruits showed smaller reductions in net photosynthetic rate (P _N ) and dark respiration rate (R _D ) after 2 d of drought and hence more positive carbon balances relative to fruiting trees. Flooding for 4 d had a more pronounced effect on...

Functional responses of Acer species to two simulated forest gap environments: leaf-level properties and photosynthesis

T.T. Lei, M.J. Lechowicz

Photosynthetica 1995, 33(2):277-289 | DOI: 10.1023/A:1022124732716

Seedlings of eight forest maple (Acer L.) species were grown outdoors through a full season under two irradiation treatments: (a) "gap edge" with a photosynthetic photon flux density of 30 µmol m-² s-¹ and a red:far-red ratio of 0.55, and (b) "gap centre" with 400 µmol m-² s-¹ and a red:far-red ratio of 1.12. Area-based leaf nitrogen concentration was greater in gap centre-grown seedlings, whereas, except for A. saccharum, area-based chlorophyll (Chl) (a+b) was higher in gap edge-grown plants. There was also a significantly lower Chl a/b ratio in gap edge-grown...

Evaluation of chlorophyll fluorescence as a tool for salt stress detection in roses

M.S. Jimenez, A.M. Gonzalez-Rodriguez, D. Morales, M.C. Cid, A.R. Socorro, M. Caballero

Photosynthetica 1995, 33(2):291-301 | DOI: 10.1023/A:1022176700857

The induction kinetic of the chlorophyll (Chl) fluorescence and the F_v/F_m ratio have been tested in order to find out the suitability of this technique to evaluate damage caused by salinity in plants of Rosa hybrida cv. Ilseta grafted on R. manetti growing in a greenhouse under non-saturating irradiance. Under these conditions salinity induced changes in plants morphology, nutrient and Chl contents and in the gas exchange parameters, but not in the F_v/F_m ratio. The Rfd index did not reveal more information. The F_v/F_m ratio as well as the fluorescence induction curves were...

Use of fluorescence probes 1-aniline-8-naphthalene sulfonate and pyrene for studying the localisation of proteins in inner membranes from wheat etioplasts

I.D. Denev, I.N. Minkov

Photosynthetica 1995, 33(2):303 | DOI: 10.1023/A:1022180817695

The fluorescence probes 1-aniline-8-naphthalene sulfonate (ANS) and pyrene were applied for characterisation of the light-induced changes in etioplast inner membranes (EPIMs) from 7 d-old dark-grown wheat seedlings (Triticum aestivum L. cv. Pobeda). The major aim was to obtain information about the localisation of membrane proteins in the EPIMs, using probes situated in different regions of the membranes. The quenching of tryptophan fluorescence showed tha the main parts of proteins were accessible to the pyrene buried in the lipid bilayer which suggests that most of the proteins also enter the lipid bilayer. The substantial quenching of the...

Carbon-based Secondary Compounds at Elevated CO₂

J. Penuelas, M. Estiarte, J. Llusia

Photosynthetica 1995, 33(2):313-319 | DOI: 10.1023/A:1022120431279

From literature sources we compiled the data on carbon-based-secondary compounds CBSC (phenolics and terpenoids) and biomass of 17 plant species grown at different CO₂ concentrations under low and high nutrient availabilities. With a low nutrient availability a possible inverse correlation was found between the biomass and CBSC changes. On the contrary, under a high nutrient availability, both the CBSC and biomass increased with elevated CO₂. The wide variation in the CBSC production among species and compounds (larger responses in phenolics than in terpenoids) indicates that the allocation to CBSC may not completely be governed...