Relationship between specific leaf area, leaf thickness, leaf water content and SPAD-502 readings in six Amazonian tree species

R.A. Marenco, S.A. Antezana-Vera, H.C.S. Nascimento

Photosynthetica 2009, 47(2):184-190 | DOI: 10.1007/s11099-009-0031-6

The aim of this work was to assess the effect of leaf thickness, leaf succulence (L_S), specific leaf area (SLA), specific leaf mass (W_s) and leaf water content (LWC) on chlorophyll (Chl) meter values in six Amazonian tree species (Carapa guianensis, Ceiba pentandra, Cynometra spruceana, Pithecolobium inaequale, Scleronema micranthum and Swietenia macrophylla). We also tested the accuracy of a general calibration equation to convert Minolta Chl meter (SPAD-502) readings into absolute Chl content. On average, SPAD values (x) increased with fresh leaf thickness (FLT [μm] = 153.9 + 0.98 x, r ²...

Diurnal changes in gas exchange and chlorophyll fluorescence parameters of Fritillaria cirrhosa and F. delavayi under field conditions

Xi-Wen Li, Shi-Lin Chen

Photosynthetica 2009, 47(2):191-198 | DOI: 10.1007/s11099-009-0032-5

To determine what factors limit the growth of wild Fritillaria cirrhosa and Fritillaria delavayi in field conditions, we investigated diurnal changes of the net photosynthetic rate (P _N) and the correlation between P _N and various environmental factors. Parameters of chlorophyll (Chl) fluorescence were evaluated to test whether ecological fragility caused the extinction of wild F. cirrhosa and F. delavayi. Our study reveals for the first time that F. cirrhosa and F. delavayi did not encounter significant stress under field conditions. A small reduction in maximum photochemical...

Photosynthetic electron transport at low temperatures in the green algal foliose lichens Lasallia pustulata and Umbilicaria hirsuta affected by manipulated levels of ribitol

J. Hájek, P. Váczi, M. Barták

Photosynthetica 2009, 47(2):199-205 | DOI: 10.1007/s11099-009-0033-4

In lichens, ribitol is known as a carbon storage compound, an osmotic agens involved effectively in cell compartments protection during dehydration of lichen thalli and as a cryoprotective compound. In our study, we investigated the effect of ribitol on photochemical processes of photosynthesis in foliose lichens [Lasallia pustulata (L.) Mérat., Umbilicaria hirsuta (Sw. ex Westr.) Hoffm.] at low temperature. The effects of three concentrations of ribitol, added externally to thalli segments on several chlorophyll (Chl) fluorescence parameters, were evaluated. The 72 h exposition to 8, 16, and 26 mM ribitol led to a concentration-dependent...

Modelling the dynamics of the electron transport rate measured by PAM fluorimetry during Rapid Light Curve experiments

J. M. Guarini, C. Moritz

Photosynthetica 2009, 47(2):206-214 | DOI: 10.1007/s11099-009-0034-3

We propose a dynamic model specifically designed to simulate changes in the photosynthetic electron transport rate, which is calculated from fluorescence measurements when plants are exposed, for a short time, to a series of increasing photon flux densities. This model simulates the dynamics of the effective yield of photochemical energy conversion from the maximum and natural chlorophyll fluorescence yields, taking into account a cumulative effect of successive irradiations on photosystems. To estimate a characteristic time of this effect on photosystems, two series of experiments were performed on two benthic diatom culture concentrations. For each...

Photosynthesis and water relations of well-watered orange plants as affected by winter and summer conditions

R.V. Ribeiro, E.C. Machado, M.G. Santos, R.F. Oliveira

Photosynthetica 2009, 47(2):215-222 | DOI: 10.1007/s11099-009-0035-2

The aim of this study was to evaluate how the summer and winter conditions affect the photosynthesis and water relations of well-watered orange trees, considering the diurnal changes in leaf gas exchange, chlorophyll (Chl) fluorescence, and leaf water potential (Ψ) of potted-plants growing in a subtropical climate. The diurnal pattern of photosynthesis in young citrus trees was not significantly affected by the environmental changes when compared the summer and winter seasons. However, citrus plants showed higher photosynthetic performance in summer, when plants fixed 2.9 times more CO₂ during the diurnal period than in the winter season....

Evidence for light-independent and steeply decreasing PSII efficiency along twig depth in four tree species

C. Yiotis, Y. Petropoulou, Y. Manetas

Photosynthetica 2009, 47(2):223-231 | DOI: 10.1007/s11099-009-0036-1

Recent reports have indicated a considerably inactivated PSII in twig cortices, in spite of the low light transmittance of overlying periderms. Corresponding information for more deeply located and less illuminated tissues like xylem rays and pith are lacking. In this investigation we aimed to characterize the efficiency of PSII and its light sensitivity along twig depth, in conjunction with the prevailing light quantity and quality. To that aim, optical methods (spectral reflectance and transmittance, chlorophyll fluorescence imaging, low temperature fluorescence spectra) and photoinhibitory treatments were applied in cut twig sections of four tree...

Fluorescence hole-burning and site-selective studies of LHCII

K. Gibasiewicz, M. Rutkowski, R. van Grondelle

Photosynthetica 2009, 47(2):232-240 | DOI: 10.1007/s11099-009-0037-0

We report the observation of two types of changes in fluorescence spectra of LHCII at 4.2 K following intense illumination of the sample with a spectrally narrow laser beam at wavelengths between 678 and 686 nm. Nonspecific changes (burning-wavelength independent) are characterized by two relatively broad bands: a positive one at ∼ 678.7 nm and a negative one at ∼ 680.8 nm. These changes reveal a ∼1.3-nm blue shift of the distribution of final emitters in LHCII, from 680.3 nm to ∼ 679.0 nm independent of the excitation wavelength. Specific fluorescence changes (burning-wavelength dependent) are characterized by a sharp hole exactly...

Effect of nitrogen-deficiency on midday photoinhibition in flag leaves of different rice (Oryza sativa L.) cultivars

E. Kumagai, T. Araki, O. Ueno

Photosynthetica 2009, 47(2):241-246 | DOI: 10.1007/s11099-009-0038-z

Effects of nitrogen (N)-deficiency on midday photoinhibition in flag leaves were compared between two contrastive Japanese rice cultivars, a traditional japonica cultivar with low yield, cv. Shirobeniya (SRB), and a japonica-indica intermediate type with high yield, cv. Akenohoshi (AKN). Both cultivars were grown under high-N and low-N conditions. At midday, low-N supply resulted in more intensive reductions in net photosynthetic rate, stomatal conductance, maximal quantum yield of photosystem II (PSII) and quantum yield of PSII electron transport in SRB than in AKN, indicating that SRB was more strongly photoinhibited than AKN under...

Photosynthetic and yield responses of an old and a modern winter wheat cultivars to short-term ozone exposure

H. Xu, S. B. Chen, D.K. Biswas, Y. G. Li, G. M. Jiang

Photosynthetica 2009, 47(2):247-254 | DOI: 10.1007/s11099-009-0039-y

In order to study the responses of winter wheat cultivars released in different years to short-term high O₃ exposure, an old cultivar ('Nongda 311', released in 1960s) and a modern one ('Yannong 19', released in 1990s) were treated with an O₃ exposure (145 ± 12 mm³ m^-3, 4 h d^-1 for 3 d) shortly after anthesis stage (> 50 % main stems blossomed). During the O₃ exposure, light-saturated photosynthetic rate (P _N) and stomatal conductance (g _s) of both cultivars decreased considerably. Elevated O₃ did not decrease dark-adapted maximum...

Thermotolerance of the photosynthetic light reactions in two Phaseolus species: a comparative study

C.M. Tsai, B.D. Hsu

Photosynthetica 2009, 47(2):255-262 | DOI: 10.1007/s11099-009-0040-5

The common bean (Phaseolus vulgaris L.) is sensitive to high temperature, while an ecologically contrasting species (Phaseolus acutifolius A. Gray) is cultivated successfully in hot environments. In this study, the two bean species were respectively acclimated to a control temperature of 25 °C and a moderately elevated temperature of 35 °C in order to compare the thermotolerance capabilities of their photosynthetic light reactions. Growth at 35 °C appeared to have no obvious adverse effect on the photosynthetic activities of the two beans, but changed their thermotolerance. After a short period of heat shock (40 °C for up to 4 h), the...

The effect of altered sink-source relations on photosynthetic traits and matter transport during the phase of reproductive growth in the annual herb Chenopodium album

Y. Yasumura

Photosynthetica 2009, 47(2):263-270 | DOI: 10.1007/s11099-009-0041-4

Annual plants transport a large portion of carbohydrates and nitrogenous compounds from leaves to seeds during the phase of reproductive growth. This study aimed to clarify how reproductive growth affects photosynthetic traits in leaves and matter transport within the plant in the annual herb Chenopodium album L. Plants were grown in pots and either reproductive tissues or axillary leaves were removed at anthesis. Matter transport was evaluated as temporal changes in dry mass (as a substitute of carbohydrates) and nitrogen content of aboveground organs: leaves, axillary leaves, stems and reproductive tissues. Photosynthetic capacity (light-saturated...

Photosynthetic net O₂ evolution enhancement as a sign of acclimation to phosphorus deficiency in bean (Phaseolus vulgaris L.) leaves

B. Kozłowska-Szerenos, A. Jarosz, S. Maleszewski

Photosynthetica 2009, 47(2):271-276 | DOI: 10.1007/s11099-009-0042-3

Primary leaves of bean (Phaseolus vulgaris L.) seedlings cultivated for 14 days in a growth chamber on complete (control) and phosphate deficient (-P) Knop liquid medium were used for measurements. The -P leaves were smaller and showed an increased specific leaf area (SLA). Their inorganic phosphate (P_i) concentration was considerably lowered. They did not show any significant changes in chlorophyll (Chl) (a + b) concentration and in their net CO₂ assimilation rate when it was estimated under the conditions close to those of the seedlings growth. Light response curves of photosynthetic net O₂ evolution...

Changes of photosynthetic activities of maize (Zea mays L.) seedlings in response to cadmium stress

H. Wang, S.C. Zhao, R.L. Liu, W. Zhou, J.Y. Jin

Photosynthetica 2009, 47(2):277-283 | DOI: 10.1007/s11099-009-0043-2

Maize (Zea mays L.) seedlings were grown in nutrient solution culture containing 0, 5, and 20 μM cadmium (Cd) and the effects on various aspects of photosynthesis were investigated after 24, 48, 96 and 168 h of Cd treatments. Photosynthetic rate (P _N) decreased after 48 h of 20 μM Cd and 96 h of 5μM Cd addition, respectively. Chl a and total Chl content in leaves declined under 48 h of Cd exposure. Chl b content decreased on extending the period of Cd exposure to 96 h. The maximum quantum efficiency and potential photosynthetic capacity of PSII, indicated by F_v/F_m and F_v/F_o,...

Drought resistance and recovery of photosystem II activity in a Mediterranean semi-deciduous shrub at the seedling stage

A. Petsas, G. Grammatikopoulos

Photosynthetica 2009, 47(2):284-292 | DOI: 10.1007/s11099-009-0044-1

Phlomis fruticosa is one of the main species of post-fire Mediterranean communities, occupying areas with post-fire grazing or altered precipitation pattern and consequently water stress imposed on seedlings of co-occurring species. Seedlings of woody perennials often differ from their mature individuals regarding their resistance of photosynthetic performance to environmental stresses. Such differences have been reported for tree species but there is a lack of information regarding shrub species. In the present study, we tried to detect changes in (PSII) activity imposed by water stress in P. fruticosa seedlings as well as its capability...

Retardation in seedling growth and induction of early senescence in plants upon caffeine exposure is related to its negative effect on Rubisco

P. Mohanpuria, S.K. Yadav

Photosynthetica 2009, 47(2):293-297 | DOI: 10.1007/s11099-009-0045-0

Adverse effect of caffeine consumption has been well documented in animals and in human beings. However, here we studied the influence of caffeine exposure on seedling growth of Arabidopsis and tobacco plants. Retardation in the seedling growth of these plants was observed when grown on MS medium plates containing 1 mM caffeine and their growth retarded further upon increasing the concentration of caffeine to 5 mM. Retardation in seedling size including both root and shoot size, yellowing and decrease in chlorophyll content of seedlings upon caffeine treatment indicated that caffeine exposure induced early senescence in plants. Therefore, the...

Occurrence and altitudinal pattern of C₄ plants on Qinghai Plateau, Qinghai province, China

M.C. Li, J.J. Zhu, L.X. Li

Photosynthetica 2009, 47(2):298-303 | DOI: 10.1007/s11099-009-0046-z

The natural occurrence and altitudinal pattern of species with C₄ photosynthesis were investigated on Qinghai Plateau, Qinghai province by using stable carbon isotopes in plant leaves and using additional data from references. A total of 58 species belonging to 10 families and 34 genera were identified using C₄ photosynthetic pathway, which is only 1.66 % of total 3 500 plant species in Qinghai province. The leading two families, i.e. Gramineae (23 species) and Chenopodiaceae (22 species) contain 77.6 % of all C₄ plants in the studied area. The number of C₄ species increased from 1 600 to 2 400 m a.s.l....

Pioneering research on C₄ leaf anatomical, physiological, and agronomic characteristics of tropical monocot and dicot plant species: Implications for crop water relations and productivity in comparison to C₃ cropping systems

M. A. El-Sharkawy

Photosynthetica 2009, 47(2):163-183 | DOI: 10.1007/s11099-009-0030-7

The review is done to summarise the history of the discoveries of the many anatomical, agronomical, and physiological aspects of C₄ photosynthesis (where the first chemical products of CO₂ fixation in illuminated leaves are four-carbon dicarboxylic acids) and to document correctly the scientists at the University of Arizona and the University of California, Davis, who made these early discoveries. The findings were milestones in plant science that occurred shortly after the biochemical pathway of C₃ photosynthesis in green algae (where the first chemical product is a three-carbon compound) was elucidated at the...

Effects of rapidly imposed water deficit on photosynthetic parameters of three C₄ grasses

A.S. Soares-Cordeiro, A.E. Carmo-Silva, A. Bernardes da Silva, J. Marques da Silva, A.J. Keys, M.C. Arrabaça

Photosynthetica 2009, 47(2):304-308 | DOI: 10.1007/s11099-009-0047-y

Water deficit, when rapidly imposed on three C₄ grasses of the different metabolic subtypes, Paspalum dilatatum Poiret (NADP-malic enzyme), Cynodon dactylon (L.) Pers (NAD-malic enzyme) and Zoysia japonica Steudel (phosphoenolpyruvate carboxykinase), caused decreases in photosynthetic rates, in the quantum yield of PS II and photochemical quenching, and in the activities of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) and phosphoenolpyruvate carboxylase (PEPC). The results provide evidence for non-stomatal limitations of photosynthesis differing in nature between the three species.

Diurnal cycle of chlorophyll fluorescence in Phalaenopsis

B. Pollet, K. Steppe, M. C. van Labeke, R. Lemeur

Photosynthetica 2009, 47(2):309-312 | DOI: 10.1007/s11099-009-0048-x

Chlorophyll (Chl) fluorescence of warm day/cool night temperature exposed Phalaenopsis plants was measured hourly during 48 h to study the simultaneous temperature and irradiance response of the photosynthetic physiology. The daily pattern of fluorescence kinetics showed abrupt changes of photochemical quenching (q_P), non-photochemical quenching (NPQ) and quantum yield of photosystem II electron transport (Φ_PSII) upon transition from day to night and vice versa. During the day, the course of Φ_PSII and NPQ was related to the air temperature pattern, while maximum quantum efficiency of PSII photochemistry...

Effects of evening and nighttime leaf wetting on stomatal behavior of Cryptomeria japonica growing in dry soil

T. Tange, K. Yanaga, H. Osawa, M. Masumori

Photosynthetica 2009, 47(2):313-316 | DOI: 10.1007/s11099-009-0049-9

To examine the hypothesis that stomatal behavior of plants in dry soil is influenced by a slow recovery from daytime water deficit, we studied the effect of repeated wetting of leaves during evening and night in Cryptomeria japonica seedlings grown in dry soil. After 7 and 10 days of leaf wetting treatment the midday leaf water potential decreased and the transpiration rate increased, respectively. Therefore, we suggest that rapid recovery from daytime water deficit could weaken the water conserving stomatal behavior that adapts to drought conditions in the roots.

Effect of 24-epibrassinolide on the photosynthetic activity of radish plants under cadmium stress

S. Anuradha, S. Seeta Ram Rao

Photosynthetica 2009, 47(2):317-320 | DOI: 10.1007/s11099-009-0050-3

The present study was conducted to study the effect of 24-epibrassinolide (EBL) on changes of plant growth, net photosynthetic rate, carbonic anhydrase (E.C. 4.2.1.1) and nitrate reductase (E.C.1.6.6.1) activities in the leaves of Raphanus sativus L. under the influence of cadmium (Cd) stress. Cd reduced plant growth, photosynthetic pigment levels, net photosynthetic rate and the activities of carbonic anhydrase and nitrate reductase. However seed application of EBL reduced the toxic effect of Cd on plant growth, pigment content, photosynthesis and enzyme activities. The studies clearly demonstrated the ameliorating effect of 24-epibrassinolide...

Jiří Čatský

Jan Květ

Photosynthetica 2009, 47(2):161-162 | DOI: 10.1007/s11099-009-0029-0