Editorial

J. Nauš

Photosynthetica 2012, 50(3):321-322 | DOI: 10.1007/s11099-012-0056-0  

Effect of Glomus mosseae on chlorophyll content, chlorophyll fluorescence parameters, and chloroplast ultrastructure of beach plum (Prunus maritima) under NaCl stress

X. M. Zai, S. N. Zhu, P. Qin, X. Y. Wang, L. Che, F. X. Luo

Photosynthetica 2012, 50(3):323-328 | DOI: 10.1007/s11099-012-0035-5  

The present study was undertaken to investigate the effect of Glomus mosseae on chlorophyll (Chl) content, Chl fluorescence parameters and chloroplast ultrastructure of beach plum seedlings under 2% NaCl stress. The results showed that compared to control, both Chl a and Chl b contents of NaCl + G. mosseae treatment were significantly lower during the salt stress, while Chl a/b ratio increased significantly. The increase of minimal fluorescence of darkadapted state (F₀), and the decrease of maximal fluorescence of dark-adapted state (F_m) and variable fluorescence (F_v) values were inhibited....

Photosynthetic limitations caused by different rates of water-deficit induction in Glycine max and Vigna unguiculata

S. C. Bertolli, G. L. Rapchan, G. M. Souza

Photosynthetica 2012, 50(3):329-336 | DOI: 10.1007/s11099-012-0036-4  

Plants are constantly subjected to variations in their surrounding environment, which affect their functioning in different ways. The influence of environmental factors on the physiology of plants depends on several factors including the intensity, duration and frequency of the variation of the external stimulus. Water deficit is one of the main limiting factors for agricultural production worldwide and affects many physiological processes in plants. The aim of this study was to analyse the effects of different rates of induced water deficit on the leaf photosynthetic responses of soybean (Glycine max L.) and cowpea (Vigna unguiculata...

Leaf shape alters the coefficients of leaf area estimation models for Saussurea stoliczkai in central Tibet

Z. Wang, L. Zhang

Photosynthetica 2012, 50(3):337-342 | DOI: 10.1007/s11099-012-0039-1  

Nondestructive methods to estimate individual leaf area (LA) accurately, by leaf length (L) and/or width (W), is helpful for the in situ and successive LA measurements. However, leaf shape and size may covary with environment and thus alter the coefficients of LA estimation models. To test such hypothesis, we carried out an experiment by measuring Saussurea stoliczkai C. B. Clarke leaves along an altitudinal transect in Damxung county, central Tibet. In July 2011, we selected seven sites at about every 150 m in altitude from 4,350 m to 5,250 m a.s.l. A total of 1,389 leaves (182 to 203 leaves for each site) were measured. For each site,...

Evaluation of reflectance spectroscopy indices for estimation of chlorophyll content in leaves of a tropical tree species

M. S. Mielke, B. Schaffer, A. C. Schilling

Photosynthetica 2012, 50(3):343-352 | DOI: 10.1007/s11099-012-0038-2  

The effectiveness of eight spectral reflectance indices for estimating chlorophyll (Chl) content in leaves of Eugenia uniflora L., a tropical tree species widely distributed throughout the world and a key species for ecosystem restoration projects, was evaluated. Spectral reflectance indices were tested using sun and shade leaves with a broad variation in leaf mass per area (LMA). Shortly after plants were exposed to chilling temperatures, there was a dramatic visible change in some sun leaves from green to red. Prior to testing Chl-related reflectance indices, the green and red leaves were separated according to the anthocyanin reflectance...

Effect of Ca/Mg ions ratio on copper accumulation, photosynthetic activity and growth of Cu²⁺-treated Salix viminalis L. 'Cannabina'

K. Borowiak, K. Drzewiecka, Z. Magdziak, M. Gąsecka, M. Mleczek

Photosynthetica 2012, 50(3):353-361 | DOI: 10.1007/s11099-012-0040-8  

The aim of the study was to the assess the influence of Ca/Mg ions ratio on the photosynthetic activity of Salix viminalis L. 'Cannabina' plants cultivated in medium enriched with Cu(NO₃)₂. The experiment was conducted in controlled conditions in a phytotron for 21 days; hence the early plant response was tested. Plants were cultivated with different Ca/Mg ions ratios, i.e. (4:1)_l, (4:1)_h, and 1:10. Plants were additionally treated with Cu(NO₃)₂ at 1, 2, and 3 mM concentration in cultivation medium. Net photosynthetic rate, stomatal conductance and transpiration were measured...

Effects of fully open-air [CO₂] elevation on leaf ultrastructure, photosynthesis, and yield of two soybean cultivars

X. Y. Hao, X. Han, S. K. Lam, T. Wheeler, H. Ju, H. R. Wang, Y. C. Li, E. D. Lin

Photosynthetica 2012, 50(3):362-370 | DOI: 10.1007/s11099-012-0043-5  

The objective of this study was to investigate the effect of elevated (550 ± 17 μmol mol^-1) CO₂ concentration ([CO₂]) on leaf ultrastructure, leaf photosynthesis and seed yield of two soybean cultivars [Glycine max (L.) Merr. cv. Zhonghuang 13 and cv. Zhonghuang 35] at the Free-Air Carbon dioxide Enrichment (FACE) experimental facility in North China. Photosynthetic acclimation occurred in soybean plants exposed to long-term elevated [CO₂] and varied with cultivars and developmental stages. Photosynthetic acclimation occurred at the beginning bloom (R1) stage for both cultivars, but at the...

Effects of postharvest pretreatments and preservative solutions on vase life longevity and flower quality of sweet pea (Lathyrus odoratus L.)

K. M. Elhindi

Photosynthetica 2012, 50(3):371-379 | DOI: 10.1007/s11099-012-0053-3  

The effects of postharvest pretreatments on vase life, keeping quality and carbohydrate concentrations in cut sweet pea (Lathyrus odoratus L.) flowers were investigated. Compared to the control, all treatments promoted floret quality and extended longevity. The cut flowers held in the solution containing sucrose + 8-hydroxyquinoline (Suc+HQS) was more effective in promoting absorption rate, achieved greater maximum fresh mass, had better water balance for a longer period, extended the vase life (up to 17 d), and delayed degradation of chlorophylls. The same treatment also enhanced the concentration of soluble carbohydrates in the petals and...

Monitoring moderate Cu and Cd toxicity by chlorophyll fluorescence and P₇₀₀ absorbance in pea leaves

B. Wodala, G. Eitel, T. N. Gyula, A. Ördög, F. Horváth

Photosynthetica 2012, 50(3):380-386 | DOI: 10.1007/s11099-012-0045-3  

We investigated the effect of moderate Cu²⁺ and Cd²⁺ stress by applying chlorophyll (Chl) fluorescence and P₇₀₀ absorbance measurements to monitor the photosynthetic electron transport activity of 3-week-old Pisum sativum L. cv. Petit Provençal plants grown in a modified Hoagland solution containing 50 μM CuSO₄ or 5 μM CdCl₂. Both heavy metals caused a slight inhibition in PSII photochemistry as indicated by the decrease in the effective quantum efficiency of PSII (Φ_PSII), the maximum electron transport capacity (ETR_max), and the maximum quantum yield for...

Contribution of leaf nitrogen to photosynthetic gas exchange in contrasting rice (Oryza sativa L.) cultivars during the grain-filling period

S. Shimoda

Photosynthetica 2012, 50(3):387-394 | DOI: 10.1007/s11099-012-0044-4  

Photosynthetic parameters and leaf carbon isotope composition (δ¹³C) in contrasting rice genotypes in relation to supplemental nitrogen (N) application and water management during the grain-filling period were compared. The changes in stomatal conductance (g _s) and ratio of intercellular to ambient CO₂ mole fraction (C _i/C _a) depended on the leaf nitrogen concentration (leaf N) in both 'Hinohikari' (temperate japonica genotype) and 'IR36' (indica genotype). In 'Hinohikari', δ¹³C reflects photosynthetic gas exchange during the grain-filling...

Responses of cotton and wheat photosynthesis and growth to cyclic variation in carbon dioxide concentration

J. A. Bunce

Photosynthetica 2012, 50(3):395-400 | DOI: 10.1007/s11099-012-0041-7  

The carbon dioxide concentration in free air carbon dioxide enrichment (FACE) systems typically has rapid fluctuations. In our FACE system, power spectral analysis of CO₂ concentration measured every second with an open path analyzer indicated peaks in variation with a period of about one minute. I used open-top chambers to expose cotton and wheat plants to either a constant elevated CO₂ concentration of 180 μmol mol^-1 above that of outside ambient air, or to the same mean CO₂ concentration, but with the CO₂ enrichment cycling between about 30 and 330 μmol mol^-1 above the concentration...

Growth, gas exchange, water-use efficiency, and carbon isotope composition of 'Gale Gala' apple trees grafted onto 9 wild Chinese rootstocks in response to drought stress

B. H. Liu, L. Cheng, D. Liang, Y. J. Zou, F. W. Ma

Photosynthetica 2012, 50(3):401-410 | DOI: 10.1007/s11099-012-0048-0  

To determine the effects of rootstock choice on the scion response to drought stress, we compared the vegetative growth, biomass accumulation, gas exchange, and water-use efficiency (WUE) of 'Gale Gala' apple (Malus domestica Borkh.) trees grafted onto nine wild Chinese Malus rootstocks. Compared with the well-watered control, drought treatment limited growth, as manifested by smaller increments in plant height (PH), trunk diameter (TD), total fresh biomass (TB), total dry biomass (TDB), total leaf area (LA), and relative growth rate (RGR). The extent of this effect differed among rootstocks. Stress conditions led to increases in the...

Investigation of the ameliorating effects of eggplant, datura, orange nightshade, local Iranian tobacco, and field tomato as rootstocks on alkali stress in tomato plants

Y. Mohsenian, H. R. Roosta, H. R. Karimi, M. Esmaeilizade

Photosynthetica 2012, 50(3):411-421 | DOI: 10.1007/s11099-012-0054-2  

Among the most important quality parameters of irrigation water used for greenhouse crops, alkalinity of water is considered critical due to its impact on soil or growing medium solution pH. In this study, plant growth, Fe content, photosynthetic pigment content, maximal quantum yield of PSII photochemistry (F_v/F_m), performance index (PI), leaf relative water content (LRWC), and soluble sugars concentration were investigated in nongrafted and grafted tomato (Lycopersicon esculentum Mill. cv. Red stone) plants onto five rootstocks of eggplant (Solanum melongena cv. Long purple), datura (Datura patula), orange...

Photosynthesis and nitrogen allocation in needles in the sun and shade crowns of hybrid larch saplings: effect of nitrogen application

Q. Z. Mao, M. Watanabe, M. Imori, Y. S. Kim, K. Kita, T. Koike

Photosynthetica 2012, 50(3):422-428 | DOI: 10.1007/s11099-012-0049-z  

We studied the effects of applying 50 kg(N) ha^-1 year^-1 of nitrogen (N) on needle photosynthesis, N allocation and nutrient content in the sun- and shade crowns of the hybrid larch F₁ (Larix gmelinii var. japonica × L. kaempferi). The light-saturated net photosynthetic rate (P _Nmax) was not significantly affected by N application or crown position, although the contents of N, P, K, and chlorophyll (Chl), and the maximum rates of carboxylation and electron transport were lower in needles of the shade crown than of the sun crown. This difference was mainly due to an increase in the...

Water relations and gas exchange in Coespeletia moritziana (Sch. Bip) Cuatrec., a giant rosette species of the high tropical Andes

F. Rada, A. Azócar, A. Rojas-Altuve

Photosynthetica 2012, 50(3):429-436 | DOI: 10.1007/s11099-012-0050-6  

Giant rosettes are ones of the most striking features of the vegetation in the high tropical Andes, with Coespeletia moritziana reaching the highest altitudes up to 4,600 m a.s.l. Different from other giant rosettes, this species grows on rock outcrops with poorly developed soils and where water availability may be limited. Two questions are addressed in this study: How does this species respond in terms of water relations to maintain favorable gas-exchange conditions? Considering that adult plants rely on a water-reserving central pith, how do early stages respond to this environment's extreme conditions? Water relations and gas-exchange studies...

Photosynthetic response of Vallisneria natans (Lour.) Hara (Hydrocharitaceae) to increasing nutrient loadings

X. L. Cai, G. Gao, X. M. Tang, J. Y. Dai, D. Chen

Photosynthetica 2012, 50(3):437-446 | DOI: 10.1007/s11099-012-0046-2  

To explore the effects of water column nutrient loading on photosynthesis of the submerged macrophyte Vallisneria natans (Lour.) Hara during the growth season (June to October), we determined the diurnal and seasonal variation in rapid light curves of plants cultivated under 4 different nutrient concentrations (N-P [mg L^-1]: (1) 0.5, 0.05; (2) 1.0, 0.1; (3) 5.0, 0.5; (4) 10.0, 1.0). Nutrient concentration significantly affected the magnitude of the rapid light curves of V. natans, but not the direction of their diurnal variations. At low nutrient conditions (N-P 1 [mg L^-1]: 0.5, 0.05),...

Physiological and biochemical responses of Theobroma cacao L. genotypes to flooding

F. Z. Bertolde, A. A. F. Almeida, C. P. Pirovani, F. P. Gomes, D. Ahnert, V. C. Baligar, R. R. Valle

Photosynthetica 2012, 50(3):447-457 | DOI: 10.1007/s11099-012-0052-4  

Flooding is common in lowlands and areas with high rainfall or excessive irrigation. A major effect of flooding is the deprivation of O₂ in the root zone, which affects several biochemical and morphophysiological plant processes. The objective of this study was to elucidate biochemical and physiological characteristics associated with tolerance to O₂ deficiency in two clonal cacao genotypes. The experiment was conducted in a greenhouse with two contrasting clones differing in flood tolerance: TSA-792 (tolerant) and TSH-774 (susceptible). Leaf gas exchange, chlorophyll (Chl) fluorescence, chemical composition and oxidative stress...

Leaf cuticular waxes and physiological parameters in alfalfa leaves as influenced by drought

Y. Ni, Y. J. Guo, Y. J. Guo, L. Han, H. Tang, M. Conyers

Photosynthetica 2012, 50(3):458-466 | DOI: 10.1007/s11099-012-0055-1  

Drought significantly constrains higher yield of alfalfa (Medicago sativa L.) in arid and semiarid areas all over the world. This study evaluated the responses of leaf cuticular wax constituents to drought treatment and their relations to gas-exchange indexes across six alfalfa cultivars widely grown in China. Water deficit was imposed by withholding water for 12 d during branching stage. Cuticular waxes on alfalfa leaves were dominated by primary alcohols (41.7-54.2%), alkanes (13.2-26.9%) and terpenes (17.5-28.9%), with small amount of aldehydes (1.4-3.4%) and unknown constituents (4.5-18.4%). Compared to total wax contents, the wax constituents...

Black leaf-clips of a commercial fluorometer increased leaf temperature during dark adaptation under high solar radiation

P. Giorio, V. Nuzzo, G. Guida, R. Albrizio

Photosynthetica 2012, 50(3):467-471 | DOI: 10.1007/s11099-012-0042-6  

The use of black leaf-clips for dark adaptation under high solar radiation conditions is reported to underestimate the maximum quantum yield of PSII photochemistry (F_v/F_m) measured by the continuous-excitation fluorometer Pocket PEA. The decrease in F_v/F_m was due to a rise in minimum fluorescence emission (F_o), probably resulting from increased leaf temperature (T_l). In field-grown tomato and pepper, fluorescence parameters and T_l in the region covered by the black leaf clip were measured in clipped leaves exposed to solar radiation during dark adaptation (clipped-only...

Evaluation of photosynthetic electron flow using simultaneous measurements of gas exchange and chlorophyll fluorescence under photorespiratory conditions

Z. P. Ye, Q. Yu, H. J. Kang

Photosynthetica 2012, 50(3):472-476 | DOI: 10.1007/s11099-012-0051-5  

Simultaneous measurements of leaf gas exchange and chlorophyll fluorescence for Koelreuteria paniculata Laxm. at 380 ± 5.6 and 600 ± 8.5 μmol mol^-1 were conducted, and the photosynthetic electron flow via photosystem II (PSII) to photosynthesis, photorespiration, and other electron-consuming processes were calculated. The results showed that the photosynthetic electron flow associated with carboxylation (J _c), oxygenation (J _o), and other electron-consuming processes (J _r) were 72.7, 45.7, and 29.4 μmol(e^-) m^-2 s^-1 at...

Is the rate of photosynthesis under blue light altered in the 7B-1 tomato mutant?

E. Ježilová, M. Fellner, V. Bergougnoux, M. Špundová

Photosynthetica 2012, 50(3):477-480 | DOI: 10.1007/s11099-012-0047-1  

Changes of photosynthesis under blue light were examined in the ABA-overproducing 7B-1 mutant in tomato. Net photosynthetic rate (P _N), stomatal conductance (g _s), intrinsic water-use efficiency (WUE_i) and chlorophyll (a+b) [Chl (a+b)] content in leaves of different insertion (1^st, 4^th and 9^th ones) were measured in 5-, 7- and 9-week-old plants. P _N, g _s, and Chl (a+b) content were mostly similar in young leaves of 7B-1 and wild type (WT) plants. With the aging of leaves, a blue-light-induced...