Lantana camara L.: a weed with great light-acclimation capacity

J. Carrión-Tacuri, A. E. Rubio-Casal, A. de Cires, M. E. Figueroa, J. M. Castillo

Photosynthetica 2011, 49(3):321 | DOI: 10.1007/s11099-011-0039-6

Plant invasions may be limited by low radiation levels in ecosystems such as forests. Lantana camara has been classified among the world's 10 worst weeds since it is invading many different habitats all around the planet. Morphological and physiological responses to different light fluxes were analyzed. L. camara was able to acclimate to moderately shaded environments, showing a high phenotypic plasticity. Morphological acclimation to low light fluxes was typified by increasing leaf size, leaf biomass, leaf area index and plant height and by reduced stomatal density and leaf thickness. Plants in full sunlight produced many more inflorescences...

Ecosystem carbon fluxes of a ryegrass and clover fodder crop in a Mediterranean environment

L. Vitale, P. di Tommasi, C. Arena, M. Oliva, T. Bertolini, S. Ranucci, A. Virzo de Santo, V. Magliulo

Photosynthetica 2011, 49(3):330 | DOI: 10.1007/s11099-011-0045-8

A mixture of ryegrass (Lolium italicum A. Braun) and clover (Trifolium alexandrinum L.) was sown in Eboli (Salerno, Southern Italy) in September 2007. Crop growth, leaf and canopy gas exchange and ecophysiological traits were monitored throughout the growth cycle. The gross primary production (GPP) was not affected by air temperature (T _air); on the contrary the ecosystem respiration (R _eco) decreased as T _air decreased while net ecosystem CO₂ exchange (NEE) increased. When was normalized with leaf area index (LAI), GPP decreased with T _air, a likely response...

Responses of pepper to waterlogging stress

L. J. Ou, X. Z. Dai, Z. Q. Zhang, X. X. Zou

Photosynthetica 2011, 49(3):339 | DOI: 10.1007/s11099-011-0043-x

One of the effective ways to address the effects of abnormal climate change on plant is to find germplasms that have better resistance to adverse environments. In this paper, we studied the responses of 5 pepper species Capsicum annuum L. (CA), C. baccatum L. (CB), C. chinense Jacquin. (CC), C. frutescens L. (CF) and C. pubescens Ruiz & Pavon (CP) as well as a wild pepper C. baccatum var. baccatum (CBY) to waterlogging stress. The results showed that warterlogging treatment greatly decreases photosynthetic pigment content, net photosynthetic rate (P _N) and stomatal conductance (g...

Photosynthesis and photoinhibition in two differently coloured varieties of Oxalis triangularis - the effect of anthocyanin content

S. L. Nielsen, A. M. Simonsen

Photosynthetica 2011, 49(3):346 | DOI: 10.1007/s11099-011-0042-y

The purpose of this study was to clarify effects of anthocyanins on photosynthesis and photoinhibition in green and red leaves of Oxalis triangularis. Gas analysis indicated that green plants had the highest apparent quantum yield for CO₂ assimilation [0.051 vs. 0.031 μmol(CO₂) μmol^-1(photon)] and the highest maximum photosynthesis [10.07 vs. 7.24 μmol(CO₂) m^-2 s^-1], while fluorescence measurements indicated that red plants had the highest PSII quantum yield [0.200 vs. 0.143 μmol(e^-) μmol^-1(photon)] and ETR_max...

Biphasic regulation of superoxide radical levels in Mn-depleted and photoactivated photosystem II

Y. G. Song, B. Liu, Y. P. Liu, L. B. Du, F. A. Villamena, Y. Liu

Photosynthetica 2011, 49(3):353 | DOI: 10.1007/s11099-011-0044-9

In the past decades, it has become clear that superoxide radical (O₂ ^.-) can be generated from photosystem II (PSII) during photosynthesis. Depending on the extent of its accumulation, O₂ ^.- plays an important role in plant physiology and pathology. The photoinhibition/repair cycle is a typical process in PSII which is mainly responsible for the survival of plants under the photoinihibition condition. It is therefore of significant importance to determine O₂ ^.- production in this cycle, and then explore how O₂ ^.- is controlled by PSII within a normal physiological...

A comparison between yellow-green and green cultivars of four vegetable species in pigments, ascorbate, photosynthesis, energy dissipation, and photoinhibition

J. H. Weng, L. F. Chien, C. Y. Jiang, F. C. Shih, H. Y. Chen

Photosynthetica 2011, 49(3):361 | DOI: 10.1007/s11099-011-0046-7

Yellow-green foliage cultivars of four vegetables grown outdoors, i.e., Chinese mustard (Brassica rapa), Chinese kale (Brassica oleracea var. alboglabra), sweet potato (Ipomoea batatas) and Chinese amaranth (Amaranthus tricolor), had lower chlorophyll (Chl) (a+b) (29-36% of green cultivars of the same species), total carotenoids (46-62%) and ascorbate (72-90%) contents per leaf area. Furthermore, yellow-green cultivars had smaller photosystem II (PSII) antenna size (65-70%) and lower photosynthetic capacity (52-63%), but higher Chl a/b (107-156%) and from low (60%) to high (129%) ratios of de-epoxidized...

Black leaf-clips increased minimum fluorescence emission in clipped leaves exposed to high solar radiation during dark adaptation

P. Giorio

Photosynthetica 2011, 49(3):371 | DOI: 10.1007/s11099-011-0040-0

Tomato and pepper leaves were clipped with black leaf clips for dark adaptation under solar radiation in the late spring or early summer 2010 in southern Italy. The leaves showed highly variable maximum PSII quantum yield (F_v/F_m = 0.026-0.802) using a continuous-excitation fluorometer Pocket PEA. These results were confirmed using the modulated fluorometer FMS1 on tomato leaves in mid summer, with F_v/F_m as low as 0.222 ± 0.277 due to nearly equal minimum (F_o) and maximum (F_m) fluorescence emission. A significant clip effect on F_v/F_m occurred...

A simple model for nondestructive leaf area estimation in bedding plants

F. Giuffrida, Y. Rouphael, S. Toscano, D. Scuderi, D. Romano, C. M. Rivera, G. Colla, C. Leonardi

Photosynthetica 2011, 49(3):380 | DOI: 10.1007/s11099-011-0041-z

Measurement of leaf area is commonly used in many horticultural research experiments, but it is generally destructive, requiring leaves to be removed for measurement. Determining the individual leaf area (LA) of bedding plants like pot marigold (Calendula officinalis L.), dahlia (Dahlia pinnata), sweet William (Dianthus barbatus L.), geranium (Pelargonium × hortorum), petunia (Petunia × hybrida), and pansy (Viola wittrockiana) involves measurements of leaf parameters such as length (L) and width (W) or some combinations of these parameters. Two experiments were carried out during spring 2010 (on two pot marigold,...

Responses of gas exchange, cellular membrane integrity, and antioxidant enzymes activities of salinity-stressed winter wheat to ozone pollution

Y. H. Zheng, Y. G. Li, W. R. Xia, H. Xu, B. Y. Su, G. M. Jiang, T. Y. Ning

Photosynthetica 2011, 49(3):389 | DOI: 10.1007/s11099-011-0047-6

A sand-culture experiment was conducted in open-top chambers which were constructed in a greenhouse to investigate the responses of salt-stressed wheat (Triticum aestivum L.) to O₃. Plant seeding of JN17 (a popular winter wheat cultivar) was grown in saltless (-S) and saline (+S, 100 mM NaCl) conditions combined with charcoal-filtered air (CF, < 5 ppb O₃) and elevated O₃ (+O₃, 80 ± 5 ppb, 8 h day^-1) for 30 d. O₃ significantly reduced net photosynthetic rate (PN), stomatal conductance, chlorophyll contents and plant biomass in -S treatment, but no considerable...

Comparative effect of 28-homobrassinolide and 24-epibrassinolide on the growth, carbonic anhydrase activity and photosynthetic efficiency of Lycopersicon esculentum

S. Hayat, S. Yadav, A. S. Wani, M. Irfan, A. Ahmad

Photosynthetica 2011, 49(3):397 | DOI: 10.1007/s11099-011-0051-x

The present piece of work highlights the comparative effects of two active forms of brassinosteroids (BRs), 28-homobrassinolide (HBL) and 24-epibrassinolide (EBL), on growth parameters, carbonic anhydrase activity and photosynthetic parameters in Lycopersicon esculentum (cv. K-21) sampled at 45 (24 h after spray) and 60 days after sowing, under natural conditions. Out of the two active forms of BR, EBL proved better than HBL in improving the above parameters, when applied as foliar spray. Of the three concentrations (10^-6 M, 10^-8 M or 10^-10 M) of HBL and EBL, 10^-8M proved best in both cases.

Application of linear models for estimation of leaf area in soybean [Glycine max (L.) Merr]

E. Bakhshandeh, B. Kamkar, J. T. Tsialtas

Photosynthetica 2011, 49(3):405 | DOI: 10.1007/s11099-011-0048-5

Leaf area estimation is an important measurement for comparing plant growth in field and pot experiments. In this study, determination of the leaf area (LA, cm²) in soybean [Glycine max (L.) Merr] involves measurements of leaf parameters such as maximum terminal leaflet length (L, cm), width (W, cm), product of length and width (LW), green leaf dry matter (GLDM) and the total number of green leaflets per plant (TNLP) as independent variables. A two-year study was carried out during 2009 (three cultivars) and 2010 (four cultivars) under field conditions to build a model for estimation of LA across soybean cultivars. Regression analysis...

Comparative effects of osmotic-, salt- and alkali stress on growth, photosynthesis, and osmotic adjustment of cotton plants

W. Chen, C. Feng, W. Guo, D. Shi, C. Yang

Photosynthetica 2011, 49(3):417 | DOI: 10.1007/s11099-011-0050-y

In this study, cotton seedlings were subjected to osmotic-, salt- and alkali stresses. The growth, photosynthesis, inorganic ions, and organic acids in the stressed seedlings were measured, to compare the mechanisms by which plants adapt to these stresses and attempt to probe the mechanisms by which plants adapt to high pH stress. Our results indicated that, at high stress intensity, both osmotic and alkali stresses showed a stronger injurious effect on growth and photosynthesis than salt stress. Cotton accumulated large amount of Na+ under salt and alkali stresses, but not under osmotic stress. In addition, the reductions of K⁺, NO₃...

Acclimation of winter wheat (Triticum aestivum, cv. Yangmai 13) to low levels of solar irradiance

Y. Zheng, B. Mai, R. Wu, Y. Feng, A. Sofo, Y. Ni, J. Sun, J. Li, J. Xu

Photosynthetica 2011, 49(3):426 | DOI: 10.1007/s11099-011-0055-6

Winter wheat is a grass species widely planted in northern and central China, where the increase of aerosols, air pollutants and population density are causing significant reduction in solar irradiance. In order to investigate the adaptation of winter wheat (Triticum aestivum L., cv. Yangmai 13) to low irradiance conditions occurring in the downstream plain of the Yangtze River (China), plants were subjected to four solar irradiance treatments (100%, 60%, 40%, and 20% of environmental incident solar irradiance). Significant increases in chlorophyll (Chl) and xanthophyll (Xan) pigments, and decreases in Chl a/b and Xan/Chl ratios...

Effects of elevated temperature on photosynthesis in desert plant Alhagi sparsifolia S

W. Xue, X. Y. Li, L. S. Lin, Y. J. Wang, L. Li

Photosynthetica 2011, 49(3):435 | DOI: 10.1007/s11099-011-0054-7

Most plants growing in temperate desert zone exhibit brief temperature-induced inhibition of photosynthesis at midday in the summer. Heat stress has been suggested to restrain the photosynthesis of desert plants like Alhagi sparsifolia S. It is therefore possible that high midday temperatures damage photosynthetic tissues, leading to the observed inhibition of photosynthesis. In this study, we investigated the mechanisms underlying heat-induced inhibition of photosynthesis in A. sparsifolia, a dominant species found at the transition zone between oasis and sandy desert on the southern fringe of the Taklamakan desert. The chlorophyll (Chl)...

Responses in the physiology and biochemistry of Korean pine (Pinus koraiensis) under supplementary UV-B radiation

Y. G. Zu, X. X. Wei, J. H. Yu, D. W. Li, H. H. Pang, L. Tong

Photosynthetica 2011, 49(3):448 | DOI: 10.1007/s11099-011-0057-4

The effect of supplementary UV-B radiation on Korean pine (Pinus koraiensis Sieb. et Zucc) was investigated. Compared with the control, the T1, T2, and T3 UV-B treatments increased by 1.40, 2.81, and 4.22 kJ m^-2 d^-1, respectively. Gas-exchange parameters, photosynthetic pigment concentrations, contents of secondary metabolites, epicuticular wax, free radical, malondialdehyde (MDA), and the activities of antioxidant enzymes were determined after 40 d of exposure. The concentrations of chlorophyll (Chl) a, Chl b, total Chl, carotenoid (Car), and the ratio Chl a/b in the pine needles were in the...

Photosynthetic properties of Quercus × hispanica Lam. and Q. suber L. under harsh Central European winter conditions

V. Holland, W. Brüggemann

Photosynthetica 2011, 49(3):459 | DOI: 10.1007/s11099-011-0052-9

In search for new forestation tree species for future Central European climate conditions, Mediterranean evergreen oak taxa are investigated for their summer drought- and winter frost-hardiness. Here we report on the winter performance of the photosynthetic apparatus of Quercus × hispanica Lam. and its evergreen parental species Q. suber L. under extraordinary harsh winter conditions. Both taxa showed a strong decline of photosystem II (PSII) quantum efficiency (F_v/F_m) with a concomitant increase in the deepoxidation state (DES) of the xanthophyll pigments depending on (severe) frost events during winter,...

van Emden, H.E.: Statistics for Terrified Biologists

J. Nauš

Photosynthetica 2011, 49(3):466 | DOI: 10.1007/s11099-011-0058-3

A mathematical model for describing light-response curves in Nicotiana tabacum L.

Z. Y. Chen, Z. S. Peng, J. Yang, W. Y. Chen, Z. M. Ou-Yang

Photosynthetica 2011, 49(3):467 | DOI: 10.1007/s11099-011-0056-5

A modified exponential model was used to describe light-response curves of Nicotiana tabacum L. The accuracies of an exponential model, a nonrectangular hyperbola model, a rectangular hyperbola model, a modified rectangular hyperbola model and the modified exponential model were evaluated by Mean square error (MSE) and Mean absolute error (MAE). The tests MSE and MAE of the modified exponential model were the lowest among the five models. The light saturation point (LSP) obtained by the exponential model, the nonrectangular hyperbola model and the rectangular hyperbola model were much lower than the measured values, and the maximum net photosynthetic...

Activity of C₄ enzymes in C₃-type herbaceous plants

M. Kocurek, J. Pilarski

Photosynthetica 2011, 49(3):473 | DOI: 10.1007/s11099-011-0053-8

The activity of enzymes characteristic for C₄-type photosynthesis was determined in different organs of two herbaceous plants: Reynoutria japonica Houtt. and Helianthus tuberosus L. The activity of phosphoenolpyruvate carboxylase (PEPC) was usually higher in the roots, some of the stem tissues and petioles in comparison to the leaf blades. The highest activity of malic enzymes (NAD-ME, NADP-ME) and phosphoenolpyruvate carboxykinase (PEPCK) was in the petioles and stem tissues of both plants and the lowest in the leaf blades and the pith of Helianthus tuberosus L.

Leaf area expansion and net photosynthetic rate of three bromegrass (Bromus) species

B. Biligetu, B. Coulman

Photosynthetica 2011, 49(3):478 | DOI: 10.1007/s11099-011-0049-4

This study measured individual leaf area expansion rate and leaf net photosynthetic rate (P _N) of meadow bromegrass (Bromus riparius Rehm.), smooth bromegrass (Bromus inermis Leyss.) and hybrid bromegrass (B. riparius × B. inermis). Smooth bromegrass expanded individual leaf area 1.5 times faster than meadow bromegrass and hybrid bromegrass. P _N was highest in smooth bromegrass, intermediate in hybrid bromegrass, and lowest in meadow bromegrass. Rapid growth of meadow bromegrass following defoliation compared to smooth bromegrass and hybrid bromegrass could not be explained by higher rates...

Erratum to High-light-induced superoxide anion radical formation in cytochrome b₆f complex from spinach as detected by EPR spectroscopy

M. Sang, X. C. Qin, W. D. Wang, J. Xie, X. B. Chen, K. B. Wang, J. P. Zhang, L. B. Li, T. Y. Kuang

Photosynthetica 2011, 49(3):472 | DOI: 10.1007/s11099-011-0059-2