Photosynthetica, 2016 (vol. 54), issue 2

Original Papers

Investigation of deleterious effects of chromium phytotoxicity and photosynthesis in wheat plant

S. Mathur, H. M. Kalaji, A. Jajoo

Photosynthetica 2016, 54(2):185-192 | DOI: 10.1007/s11099-016-0198-6  

Increasing human and industrial activities lead to heavy metal pollution. Heavy metal chromium (Cr) is considered to be a serious environmental contaminant for the biota. Phytotoxic effects of Cr were studied in wheat plants. Growth parameters were largely inhibited as a result of disturbances in the plant cell metabolism in response to Cr toxicity. Chromium toxicity led to decline in a number of active reaction centres of PSII, rate of electron transport, and change in PSII heterogeneity. Chromium did not cause any change in heterogeneity of the reducing side. A significant change in antenna size heterogeneity of PSII occurred in response to Cr toxicity....

Chlorophyll fluorescence upper-to-lower-leaf ratio for determination of irrigation time for Pentas lanceolata

C. W. Wu, M. C. Lee, Y. L. Peng, T. Y. Chou, K. H. Lin, Y. S. Chang

Photosynthetica 2016, 54(2):193-200 | DOI: 10.1007/s11099-015-0175-5  

The objective of this study was to use nondestructive measurements as the precise irrigation indices for potted star cluster (Pentas lanceolata). Drought stress was imposed on plants for 0, 3, 5, 7, 12, and 16 d by withholding water. Measurements were conducted on the third leaf counted from the apex (upper leaves) and on the third leaf from the bottom (lower leaves). Within the range of soil water content (SWC) from 10 to 45%, leaf water potential (WP), SWC, and soil matric potential (SMP), chlorophyll fluorescence, photochemical reflectance index (PRI), adjusted normalized difference vegetation index (aNDVI), and the reflectance (R) at 1950...

Relationship between flavonoids and photoprotection in shade-developed Erigeron breviscapus transferred to sunlight

R. Zhou, W. H. Su, G. F. Zhang, Y. N. Zhang, X. R. Guo

Photosynthetica 2016, 54(2):201-209 | DOI: 10.1007/s11099-016-0074-4  

Flavonoids are thought to participate in protection of the photosynthetic apparatus against photoinhibition under excessive light. Flavone glycoside, scutellarin, is a main active ingredient extracted from Erigeron breviscapus, the plant used in Chinese medicine. Shade-developed leaves of E. breviscapus were transferred from shade to full sunlight to quantify a relationship between the concentration of leaf scutellarin and tolerance to high radiation stress or the recovery from photoinhibition. The maximal quantum yield of PSII photochemistry showed a diurnal fluctuation in both shaded and sunlit leaves throughout the day. It indicated...

Effects of hypo- and hypersalinity on photosynthetic performance of Sargassum fusiforme (Fucales, Heterokontophyta)

X. J. Xie, X. L. Wang, L. D. Lin, L. W. He, W. H. Gu, S. Gao, X. F. Yan, G. H. Pan, M. J. Wu, G. C. Wang

Photosynthetica 2016, 54(2):210-218 | DOI: 10.1007/s11099-015-0169-3  

Photoprotection mechanisms protect photosynthetic organisms, especially under stress conditions, against photodamage that may inhibit photosynthesis. We investigated the effects of short-term immersion in hypo- and hypersalinity sea water on the photosynthesis and xanthophyll cycle in Sargassum fusiforme (Harvey) Setchell. The results indicated that under moderate light [110 μmol(photon) m^-2 s^-1], the effective quantum yield of PSII was not reduced in S. fusiforme fronds after 1 h in hyposalinity conditions, even in fresh water, but it was significantly affected by extreme hypersalinity treatment (90‰ sea...

Effects of solar UV radiation and temperature on morphology and photosynthetic performance of Chaetoceros curvisetus

W. Guan, X. Peng, S. Lu

Photosynthetica 2016, 54(2):219-225 | DOI: 10.1007/s11099-015-0170-x  

This study investigated the effect of solar ultraviolet radiation (UVR) and temperature on a chain length and photosynthetic performance of diatom Chaetorceros curvisetus. The cells were cultured in large quartz tubes and exposed to PAR, PAR + UV-A (PA), or PAR + UV-A + UV-B (PAB) radiation at 20°C and 28°C for six days, respectively. After recovery for 1 h, the cells were exposed again to three different radiations for 1 h. Then, a change in the photochemical efficiency (F_PSII) was examined and UVR-induced photoinhibition was calculated. The percentage of long chains (more than five single cells per chain) in C. curvisetus...

Different mechanisms of photosynthetic response to drought stress in tomato and violet orychophragmus

W. H. Sun, Y. Y. Wu, X. Y. Wen, S. J. Xiong, H. G. He, Y. Wang, G. Q. Lu

Photosynthetica 2016, 54(2):226-233 | DOI: 10.1007/s11099-015-0177-3  

Carbonic anhydrase (CA) catalyzes reversible hydration of CO₂ and it can compensate for the lack of H₂O and CO₂ in plants under stress conditions. Antioxidative enzymes play a key role in scavenging reactive oxygen species and in protecting plant cells against toxic effects. Tomato represents a stress-sensitive plant while violet orychophragmus belongs to adversity-resistant plants. In order to study the drought responses in tomato and violet orychophragmus plants, CA and antioxidative enzyme activities, photosynthetic capacity, and water potential were determined in plants under drought stress. We found that there...

Bioregulators protected photosynthetic machinery by inducing expression of photorespiratory genes under water stress in chickpea

T. V. Vineeth, P. Kumar, G. K. Krishna

Photosynthetica 2016, 54(2):234-242 | DOI: 10.1007/s11099-016-0073-5  

Globally, water deficit is one of the major constraints in chickpea (Cicer arietinum L.) production due to substantial reduction in photosynthesis. Photorespiration often enhances under stress thereby protecting the photosynthetic apparatus from photoinhibition. Application of bioregulators is an alternative to counter adverse effects of water stress. Thus, in order to analyze the role of bioregulators in protecting the photosynthetic machinery under water stress, we performed an experiment with two contrasting chickpea varieties, i.e., Pusa 362 (Desi type) and Pusa 1108 (Kabuli type). Water deficit stress was imposed at the vegetative...

Ecophysiological responses of Eichhornia crassipes (Mart.) Solms to As⁵⁺ under different stress conditions

A. C. Meneguelli-Souza, A. P. Vitória, T. O. Vieira, M. S. O. Degli-Esposti, C. M. M. Souza

Photosynthetica 2016, 54(2):243-250 | DOI: 10.1007/s11099-015-0174-6  

Arsenic is a critical contaminant that is released into the environment through geochemical processes and anthropic actions. Two independent hydroponic experiments were performed to evaluate the ecophysiological responses of water hyacinth [Eichhornia crassipes (Mart.) Solms] to As under various stress conditions. In experiment 1, water hyacinth was exposed to As⁵⁺ at concentrations of 0, 0.2, 2.0, and 20 mg L^-1 for 0, 2, and 4 d; in experiment 2, water hyacinth was exposed at concentrations of 0, 0.025, 0.05, and 0.1 mg L^-1 for 0, 10, and 20 d. In both experiments, As accumulation in plant tissue was proportional...

Effects of low irradiation on photosynthesis and antioxidant enzyme activities in cucumber during ripening stage

Z. Q. Yang, C. H. Yuan, W. Han, Y. X. Li, F. Xiao

Photosynthetica 2016, 54(2):251-258 | DOI: 10.1007/s11099-015-0179-1  

In order to investigate the effects of low irradiation (LI) on cucumber (Cucumis sativus L. cv. Jinyou 35) during a ripening stage, our experiment was carried out in a climate chamber. Two levels of PAR were set for plants: normal irradiation [NI, 600 μmol(photon) m^-2 s^-1] and low irradiation [LI, 100 μmol(photon) m^-2 s^-1], respectively. The experiments lasted for 9 d; then both groups of plants were transferred under NI to recover for 16 d. The plants showed severe chlorosis after the LI treatment. Chlorophyll (Chl) a, initial slope, photosynthetic rate at saturating irradiation (P...

Effect of low irradiance on the photosynthetic performance and spiking of Phalaenopsis

Y. C. Liu, C. H. Liu, Y. C. Lin, C. H. Lu, W. H. Chen, H. L. Wang

Photosynthetica 2016, 54(2):259-266 | DOI: 10.1007/s11099-016-0079-z  

Lowering irradiance can delay the flower stalk, i.e., spike development, in order to schedule flowering time of Phalaenopsis; however, the effect on photosynthetic performance and spiking inhibition remains poorly understood. We compared light and shade treatments of Phalaenopsis aphrodite subsp. formosana in order to determine how limiting light affects day-night changes in the photosynthetic capacity of leaves and the carbon pool of leaves and stems resulting in delayed spiking. The low irradiance treatment [20 μmol(photon) m^-2 s^-1] for six weeks did not affect potential functions of photosynthetic apparatus...

Zinc soil application enhances photosynthetic capacity and antioxidant enzyme activities in almond seedlings affected by salinity stress

A. Amiri, B. Baninasab, C. Ghobadi, A. H. Khoshgoftarmanesh

Photosynthetica 2016, 54(2):267-274 | DOI: 10.1007/s11099-016-0078-0  

Zinc is a critical mineral nutrient that protects plant cells from salt-induced cell damage. We tested whether the application of Zn at various concentrations [0, 5, 10, or 20 mg kg^-1(soil)] would protect almond (Prunus amygdalus) seedlings subjected to salt stress (0, 30, 60, or 90 mM NaCl). All concentrations of Zn, particularly the application of 10 and 20 mg kg^-1, increased the net photosynthetic rate, stomatal conductance, the maximal efficiency of PSII photochemistry, and a proline content in almond seedlings grown under salt stress; 20 mg(Zn) kg^-1 was the most effective concentration. The activity of superoxide...

Submergence-tolerant rice withstands complete submergence even in saline water: Probing through chlorophyll a fluorescence induction O-J-I-P transients

R. K. Sarkar, Anuprita Ray

Photosynthetica 2016, 54(2):275-287 | DOI: 10.1007/s11099-016-0082-4  

Plants experience multiple abiotic stresses during the same growing season. The implications of submergence with and without saline water on growth and survival were investigated using four contrasting rice cultivars, FR13A (submergence-tolerant, salinity-susceptible), IR42 (susceptible to salinity and submergence), and Rashpanjor and AC39416 (salinity-tolerant, submergence-susceptible). Though both FR13A and IR42 showed sensitivity to salinity, FR13A exhibited higher initial biomass as well as maintained greater dry mass under saline condition. Greater reduction of chlorophyll (Chl) contents due to salinity was observed in the susceptible cultivars,...

The effect of methanol on photosynthetic parameters of bean (Phaseolus vulgaris L.) under water deficit

N. Armand, H. Amiri, A. Ismaili

Photosynthetica 2016, 54(2):288-294 | DOI: 10.1007/s11099-015-0178-2  

Water availability is the main factor limiting crop growth and productivity in dry regions. This study was carried out in order to determine the effect of spraying methanol solution on the photosynthetic characteristics of bean plants. The main aim of our experiment was to improve plant performance under stress caused by water shortage. Two factors were involved: water-deficit stress, such as severe stress (25% of field capacity), mild stress (75% of field capacity), and no stress (100% of field capacity), and application of methanol solution spray at four concentrations: control (without spraying), 10, 20, and 30%. Methanol was applied three times...

Chilling tolerance and early vigour-related characteristics evaluated in two Miscanthus genotypes

S. Fonteyne, P. Lootens, H. Muylle, W. van den Ende, T. de Swaef, D. Reheul, I. Roldan-Ruiz

Photosynthetica 2016, 54(2):295-306 | DOI: 10.1007/s11099-016-0193-y  

A long growing season, mediated by the ability to grow at low temperatures early in the season, can result in higher yields in biomass of crop Miscanthus. In this paper, the chilling tolerance of two highly productive Miscanthus genotypes, the widely planted Miscanthus × giganteus and the Miscanthus sinensis genotype 'Goliath', was studied. Measurements in the field as well as under controlled conditions were combined with the main purpose to create basic comparison tools in order to investigate chilling tolerance in Miscanthus in relation to its field performance. Under field conditions, M. × giganteus...

Photosynthesis, antioxidant status and gas-exchange are altered by glyphosate application in peanut leaves

D. E. M. Radwan, K. A. Fayez

Photosynthetica 2016, 54(2):307-316 | DOI: 10.1007/s11099-016-0075-3  

Glyphosate herbicide caused oxidative stress and exhibited negative effects on photosynthesis and gas exchange of peanut [Arachis hypogaea L. cv. Giza (G) 5 and 6] leaves. We demonstrated that glyphosate caused various morphological symptoms, such as chlorosis, yellowing, and appearance of curly edges in leaves treated with high doses of herbicide in both cultivars; however, the G5 cultivar was more sensitive and showed severer symptoms. Glyphosate lowered photosynthesis and reduced contents of pigments and proteins as well as free amino acids in both cultivars. The gas-exchange parameters, such as photosynthetic (P _N) and...

Review

Prospects of photosynthetic research for increasing agricultural productivity, with emphasis on the tropical C₄ Amaranthus and the cassava C₃-C₄ crops

M. A. El-Sharkawy

Photosynthetica 2016, 54(2):161-184 | DOI: 10.1007/s11099-016-0204-z  

Productivity of most improved major food crops showed stagnation in the past decades. As human population is projected to reach 9-10 billion by the end of the 21^st century, agricultural productivity must be increased to ensure their demands. Photosynthetic capacity is the basic process underlying primary biological productivity in green plants and enhancing it might lead to increasing potential of the crop yields. Several approaches may improve the photosynthetic capacity, including integrated systems management, in order to close wide gaps between actual farmer's and the optimum obtainable yield. Conventional and molecular genetic improvement...

Brief Communications

Photosynthesis and chlorophyll fluorescence responses of Populus sibirica to water deficit in a desertification area in Mongolia

T. Y. Lee, S. Y. Woo, M. J. Kwak, K. Inkyin, K. E. Lee, J. H. Jang, I. R. Kim

Photosynthetica 2016, 54(2):317-320 | DOI: 10.1007/s11099-015-0180-8  

In the present study, photosynthetic traits and chlorophyll (Chl) fluorescence parameters of Populus sibirica grown under different irrigation regimes were investigated to estimate seedling growth and vitality for reforestation of a desertification area. According to our results, photosynthesis and Chl fluorescence were significantly affected by water deficit only under severe drought conditions.