Short-term effects of extensive fertilization on community composition and carbon uptake in a Pannonian loess grassland

S. Z. Czóbel, Z. Németh, O. Szirmai, C. S. Gyuricza, A. Tóth, J. Házi, D. Vikár, K. Penksza

Photosynthetica 2013, 51(4):490-496 | DOI: 10.1007/s11099-013-0052-z  

Among the most extended ecosystems of the temperate zone, the seminatural, dry grasslands constitute a substantial proportion in the Carpathian Basin. The aim of our present study was to investigate the short-term effect of extensive fertilization on the species composition and CO₂ exchange of loess grassland at community level. The in situ investigation of the latter parameter have not been yet carried out in Pannonian loess grasslands. Most of the parameters studied showed a considerable interannual variation both in the fertilized and in the control stands. As a result of the treatment, the average species number of the fertilized...

Developmental changes in energy dissipation in etiolated wheat seedlings during the greening process

E. V. Garmash, O. V. Dymova, R. V. Malyshev, S. N. Plyusnina, T. K. Golovko

Photosynthetica 2013, 51(4):497-508 | DOI: 10.1007/s11099-013-0044-z  

We studied the developmental changes in photosynthetic and respiration rates and thermal dissipation processes connected with chloroplasts and mitochondria activity in etiolated wheat (Triticum aestivum L., var. Irgina) seedlings during the greening process. Etioplasts gradually developed into mature chloroplasts under continuous light [190 μmol(photon) m^-2 s^-1] for 48 h in 5-day-dark-grown seedlings. The net photosynthetic rate of irradiated leaves became positive after 6 h of illumination and increased further. The first two hours of de-etiolation were characterized by low values of maximum (F_v/F_m)...

Effects of addition of external nitric oxide on the allocation of photosynthetic electron flux in Rumex K-1 leaves under osmotic shock

H. D. Li, W. B. Wang, P. M. Li, K. Xu, H. Y. Gao, J. Xiao

Photosynthetica 2013, 51(4):509-516 | DOI: 10.1007/s11099-013-0049-7  

Photosynthetic electron flux allocation, stomatal conductance, and the activities of key enzymes involved in photosynthesis were investigated in Rumex K-1 leaves to better understand the role of nitric oxide (NO) in photoprotection under osmotic stress caused by polyethylene glycol. Gas exchange and chlorophyll fluorescence were measured simultaneously with a portable photosynthesis system integrated with a pulse modulated fluorometer to calculate allocation of photosynthetic electron fluxes. Osmotic stress decreased stomatal conductance, photosynthetic carbon assimilation, and nitrate assimilation, increased Mehler reaction, and resulted in...

Isolation and characterization of oxygen-evolving photosystem II particles and photosystem II core complex from the filamentous cyanobacterium Spirulina platensis

E. Šetlíková, D. Sofrová, V. Kovář, P. Budáč

Photosynthetica 2013, 51(4):517-530 | DOI: 10.1007/s11099-013-0051-0  

Photosystem (PS) II particles retaining a high rate of O₂ evolution were isolated from the mesophilic filamentous cyanobacterium, Spirulina platensis. To achieve high production of PSII complexes in the cells, irradiance from halogen incandescent lamps was used. Disruption of cells by vibration of glass beads proved to be the most suitable procedure for isolation of thylakoid membranes. The selectivity of detergents for PSII particle preparation rose in the order of Triton X-100 < decyl-β-D-glucopyranoside < dodecyldimethyl-aminooxide < n-heptyl-β-D-thioglucoside < N-dodecyl-N,N-dimethylammonio-3-propane...

Development of models for estimating leaf chlorophyll and nitrogen contents in tree species with respect to seasonal changes

D. Mizusaki, K. Umeki, T. Honjo

Photosynthetica 2013, 51(4):531-540 | DOI: 10.1007/s11099-013-0050-1  

Models were developed to estimate nondestructively chlorophyll (Chl) content per unit of leaf area (Chl_area) and nitrogen content per unit of leaf area (N_area) using readings of two optical meters for five warm-temperate, evergreen, broadleaved tree species (Castanopsis sieboldii, Cinnamomum tenuifolium, Eurya japonica, Machilus thunbergii, and Neolitsea sericea). It was determined whether models should be adjusted seasonally. Readings (were obtained six times during a year period and Chl_area and N_area were determined using destructive methods. Bayesian inference was used to estimate parameters...

Influence of foliar-applied triacontanol on growth, gas exchange characteristics, and chlorophyll fluorescence at different growth stages in wheat under saline conditions

S. Perveen, M. Shahbaz, M. Ashraf

Photosynthetica 2013, 51(4):541-551 | DOI: 10.1007/s11099-013-0054-x  

A greenhouse experiment was conducted to examine the effect of foliar application of triacontanol (TRIA) on two cultivars (cv. S-24 and MH-97) of wheat (Triticum aestivum L.) at different growth stages. Plants were grown in full strength Hoagland's nutrient solution under salt stress (150 mM NaCl) or control (0 mM NaCl) conditions. Three TRIA concentrations (0, 10, and 20 μM) were sprayed over leaves at three different growth stages, i.e. vegetative (V), boot (B), and vegetative + boot (VB) stages (two sprays on same plants, i.e., the first at 30-d-old plants and the second 78-d-old plants). Salt stress decreased significantly...

Gender, mediterranean drought, and seasonality: photosystem II photochemistry in Pistacia lentiscus L.

S. Ait Said, F. Torre, A. Derridj, T. Gauquelin, J. P. Mevy

Photosynthetica 2013, 51(4):552-564 | DOI: 10.1007/s11099-013-0055-9  

In this work, photosystem II (PSII) photochemistry, leaf water potential, and pigment contents of male and female Pistacia lentiscus L. were investigated during a seasonal cycle at three different, arid locations: superior semiarid, inferior semiarid, and arid. The results showed that the gender, season, and the site conditions interacted to influence the quantum yield and pigment contents in P. lentiscus. Predawn leaf water status was determined only by the site and season. The annual patterns of PSII maximum quantum efficiency (F_v/F_m) were characterized by a suboptimal activity during the winter, especially, populations...

Effect of chromate on photosynthesis in Cr(VI)-resistant Chlorella

S. N. Yewalkar, K. N. Dhumal, J. K. Sainis

Photosynthetica 2013, 51(4):565-573 | DOI: 10.1007/s11099-013-0056-8  

Chromate-resistant Chlorella spp. isolated from effluents of electroplating industry could grow in the presence of 30 μM K₂Cr₂O₇. Since photosynthesis is sensitive to oxidative stress, chromate toxicity to photosynthesis was examined in this algal isolate. Chromate [Cr(VI)] up to 100 μM was found to stimulate photosynthesis, while 90% inhibition was found, when the cells were incubated with 1 mM Cr(VI) for 4 h. Photosystem (PS) II was inhibited by 80% and PSI by 40% after such Cr(VI) treatment. Thermoluminescence studies on cells treated with 1 mM Cr(VI) for 4 h showed that S₂Q_A ^-...

Effects of drought stress on the evergreen Quercus ilex L., the deciduous Q. robur L. and their hybrid Q. × turneri Willd.

S. Koller, V. Holland, W. Brüggemann

Photosynthetica 2013, 51(4):574-582 | DOI: 10.1007/s11099-013-0058-6  

Five-year-old trees of deciduous Quercus robur L., evergreen Q. ilex L., and their semideciduous hybrid, Q. × turneri Willd. (var. pseudoturneri), growing in pots, were subjected to drought stress by withholding water for 18-22 days, until leaf water potentials decreased below -2 MPa. Gas-exchange rates, oxygen evolution, and modulated chlorophyll (Chl) fluorescence measurements revealed that by strong stomata closure and declining photosynthetic capacity down to approximately 50%, all three taxa responded with strongly reduced photosynthesis rates. In Q. robur, photochemical quenching of the drought-stressed...

Role of cyanide-resistant respiration during light-induced attraction of predators to herbivore-infested leaves

H. Q. Feng, K. Sun, Y. Wei, R. F. Wang, L. Y. Jia, J. P. Zhang, Y. Li

Photosynthetica 2013, 51(4):583-592 | DOI: 10.1007/s11099-013-0057-7  

The present work showed that spider mite-infested leaves placed in the light were more attractive to predatory mites than the infested leaves placed in the dark; furthermore, an increase in the light intensity enhanced this attractiveness. However, the increase of the light intensity did not change the attractiveness of the uninfested leaves to predatory mites. The capacity of cyanide-resistant respiration and the photosynthetic rates of both the infested and uninfested leaves increased with increasing light intensities, whereas the photosystem (PS) II chlorophyll (Chl) fluorescence decreased. The increase of the capacity of cyanide-resistant respiration...

Effect of nitrogen application and elevated CO₂ on photosynthetic gas exchange and electron transport in wheat leaves

X. C. Zhang, X. F. Yu, Y. F. Ma

Photosynthetica 2013, 51(4):593-602 | DOI: 10.1007/s11099-013-0059-5  

Nitrogen (N) availability is a critical factor affecting photosynthetic acclimation of C₃ plants under elevated atmospheric CO₂ concentration ([CO₂]_e). However, current understanding of N effects on photosynthetic electron transport rate and partitioning, as well as its impact on photosynthesis under [CO₂]_e, is inadequate. Using controlled environment open-top chambers, wheat (Triticum aestivum L.) was grown at two N levels (0 and 200 mg(N) kg^-1 soil) and two atmospheric CO₂ concentrations of 400 ([CO₂]_a) and 760 μmol mol^-1([CO₂]_e)...

Effects of water stress and fertilization on leaf gas exchange and photosynthetic light-response curves of Bothriochloa ischaemum L.

W. Z. Xu, X. P. Deng, B. C. Xu

Photosynthetica 2013, 51(4):603-612 | DOI: 10.1007/s11099-013-0061-y  

Bothriochloa ischaemum L. is an important species in many temperate regions, but information about the interactive effects of water stress and fertilization on its photosynthetic characteristics was inadequate. A pot experiment was conducted to investigate the effects of three water [80% (HW), 40% (MW), and 20% (LW) of field capacity (FC)] and four fertilization regimes [nitrogen (N), phosphorus (P), nitrogen with phosphorus (NP), and no fertilization] on leaf photosynthesis. Leaf gas exchange and photosynthetic light-response curves were measured at the flowering phase of B. ischaemum. Water stress decreased not only the leaf gas-exchange...

Leaf area estimation in muskmelon by allometry

E. Misle, B. Kahlaoui, M. Hachicha, P. Alvarado

Photosynthetica 2013, 51(4):613-620 | DOI: 10.1007/s11099-013-0062-x  

This study developed a method for estimating the leaf area (LA) of muskmelon by using allometry. The best linear measure was evaluated first, testing both a leaf length and width (W). Leaf samples were collected from plants grown in containers of different sizes, leaves of four cultivars, at different develpoment stages, and of different leaf sizes. Two constants of a power equation were determined for relating allometrically a linear leaf measure and LA, in a greenhouse crop. W proved to be a better fit than the leaf length. The maximum attainable W and LA were estimated at W_x = 15.4 cm and LA_x = 174.1 cm². The indicators...

Salinity response pattern and isolation of catalase gene from halophyte plant Aeluropus littoralis

M. Modarresi, G. A. Nematzadeh, F. Moradian

Photosynthetica 2013, 51(4):621-629 | DOI: 10.1007/s11099-013-0060-z  

The role of the antioxidant defense system in salt tolerance of Aeluropus littoralis has not been yet reported; therefore in the present study, the changes of catalase (CAT) activity in this halophyte plant was investigated and CAT gene was isolated. The leaves of treated and control plants were harvested at various times, starting 1 day prior to initiating treatment, then periodically at 72-h intervals for 21 days. The data collected showed that CAT activity increased significantly with time in plants treated with 200, 400, and 600 mM NaCl when compared with the control plants. Maximum enzyme activity was observed between the 6^th...

Effect of high temperature on dehydration-induced alterations in photosynthetic characteristics of the resurrection plant Haberlea rhodopensis

M. Velitchkova, V. Doltchinkova, D. Lazarova, G. Mihailova, S. Doncheva, K. Georgieva

Photosynthetica 2013, 51(4):630-640 | DOI: 10.1007/s11099-013-0063-9  

The effect of high temperature (HT) and dehydration on the activity of photosynthetic apparatus and its ability to restore membrane properties, oxygen evolution, and energy distribution upon rehydration were investigated in a resurrection plant, Haberlea rhodopensis. Plants growing under low irradiance in their natural habitat were desiccated to air-dry state at a similar light intensity [about 30 μol(photon) m^-2 s^-1] under optimal day/night (23/20°C) or high (38/30°C) temperature. Our results showed that HT alone reduced the photosynthetic activity and desiccation of plants at 38°C and it had more detrimental effect...

Effects of exogenous nitric oxide on photosynthesis

D. Procházková, D. Haisel, N. Wilhelmová, D. Pavlíková, J. Száková

Photosynthetica 2013, 51(4):483-489 | DOI: 10.1007/s11099-013-0053-y  

Nitric oxide (NO) is an important signalling molecule with diverse physiological functions in plants. In plant cell, it is synthesised in several metabolic ways either enzymatically or nonenzymatically. Due to its high reactivity, it could be also cytotoxic in dependence on concentration. Such effects could be also mediated by NO-derived compounds. However, the role of NO in photosynthetic apparatus arrangement and in photosynthetic performance is poorly understood as indicated by a number of studies in this field with often conflicting results. This review brings a short survey of the role of exogenous NO in photosynthesis under physiological and...

Lubomír Nátr

J. Krekule

Photosynthetica 2013, 51(4):481-482 | DOI: 10.1007/s11099-013-0064-8