Photosynthetica, 2020 (vol. 58), issue 3

Ultrasonic seed treatment and Cu application modulate photosynthesis, grain quality, and Cu concentrations in aromatic rice

Z. MO, Q. LIU, W. XIE, U. ASHRAF, M. ABRAR, S. PAN, M. DUAN, H. TIAN, S. WANG, X. TANG

Photosynthetica 2020, 58(3):682-691 | DOI: 10.32615/ps.2020.009

The present study investigated the effects of ultrasonic seed treatment and Cu application on grain yield, photosynthesis, grain quality, and Cu contents of aromatic rice. The ultrasonic treated and nontreated seeds of two aromatic rice cultivars, i.e., Nongxiang 18 and Meixiangzhan 2, were sown in Cu-contaminated soil with 1.5 and 3.0 g(Cu) m-2 whereas the soil without Cu application was taken as control (CK). Ultrasonic seed treatment and Cu application increased grain yield by 2.7-33.5% in Nongxiang 18 and by 12.9-20.2% in Meixiangzhan 2 owing to substantial improvements in morphophysiological and yield-related traits. Both ultrasonic...

Silicon improves the photosynthetic performance of black pepper plants inoculated with Fusarium solani f. sp. piperis

V. DꞌADDAZIO, J.V.G. SILVA, A.S. JARDIM, L.L. LONGUE, R.A.A. SANTOS, A.A. FERNANDES, M.B. SILVA, D.M. SILVA, T.A. SANTOS, E.R. SCHMILDT, L.H. PFENNING, A.R. FALQUETO

Photosynthetica 2020, 58(3):692-701 | DOI: 10.32615/ps.2019.182

This study evaluated the effect of silicon (Si)-supplementation in controlling the fusariosis in two Piper nigrum cultivars (Bragantina and Kottanadan). We hypothesized that susceptible cultivar improves the photosynthetic performance with Si-supplementation. Under greenhouse conditions, six-month-old plants were treated with silicon 30 and 15 d before inoculation with Fusarium solani f. sp. piperis and compared with untreated plants and with healthy control plants. All samples remained photosynthetically active after infection. Chlorophyll content, chlorophyll a fluorescence, and leaf gas-exchange parameters were less affected...

Transcription analysis of chlorophyll biosynthesis in wildtype and chlorophyll b-lacking rice (Oryza sativa L.)

M.K. NGUYEN, T.H. SHIH, S.H. LIN, W.D HUANG, C.M. YANG

Photosynthetica 2020, 58(3):702-711 | DOI: 10.32615/ps.2020.022

The aim of the present study was to investigate the photosynthetic properties and transcriptomic profiles of wildtype and chlorophyll (Chl) b-lacking rice (Oryza sativa L.). The plastid ultrastructure of the Chl b-lacking rice (i.e., loss of starch granules, abundant vesicles, and abundant plastoglobuli) indicated abnormal plastid development, whereas the analysis of transcriptome profiles and differentially expressed genes revealed that gene encoding PsbR (PSII core protein) was downregulated in the mutant, thereby reducing the Chl accumulation of the mutant. Meanwhile, in regards to Chl biosynthesis and degradation pathways,...

Effects of exogenous zinc on the photosynthesis and carbonic anhydrase activity of millet (Setaria italica L.)

M.L. CAO, Y.X. LI, H.L. DU

Photosynthetica 2020, 58(3):712-719 | DOI: 10.32615/ps.2020.018

This study aimed to evaluate the effects of Zn on the growth safety and activity of carbonic anhydrase (CA) in foxtail millet (Setaria italica L.). The photosynthetic characteristics, CA activity, and relative gene expression of different varieties of millet at the seedling stage were studied by spraying Zn solution under pot experiment and indoor culture conditions. Results showed that spraying low-concentration Zn solution (20, 40, and 60 mg L-1) reduced malondialdehyde content and intercellular CO2 concentration (Ci) but increased antioxidant enzyme activity, pigment content, and photosynthetic...

Endogenous ascorbic acid delays ethylene-induced leaf senescence in Arabidopsis thaliana

X.T. ZHENG, Z.C. YU, X.F. CHEN, M.L. CAI, Y.Z. WANG, C.L. PENG

Photosynthetica 2020, 58(3):720-731 | DOI: 10.32615/ps.2020.028

Leaf senescence is an important event in the plant life cycle. Ethylene and ascorbic acid (AsA) both regulate the leaf senescence process. The role of endogenous AsA in ethylene-induced leaf senescence was explored in two independent endogenous AsA changing Arabidopsis thaliana mutants. The line vtc2-1 with a single base change in VTC was AsA-deficient mutant; the GLDH-overexpressing line (GLDHOE) driven by the CaMV 35S promoter was AsA-overaccumulating mutant. After spraying 600 μM ethephon for 6 d, vtc2-1 showed the most serious leaf chlorosis, reactive oxygen species (ROS) accumulation, chlorophyll breakdown,...

Light reacclimatization of lower leaves in C4 maize canopies grown at two planting densities

T. YABIKU, S. AKAMATSU, O. UENO

Photosynthetica 2020, 58(3):732-739 | DOI: 10.32615/ps.2020.029

C4 plants have high photosynthetic capacity but are inefficient under low light. In a canopy, lower leaves developed under high light are progressively shaded. To elucidate how lower leaves in a C4 canopy reacclimatize to low light, we investigated maize canopies differing in light environment grown at standard and low planting densities (SPD, LPD). Although upper leaves at SPD and both upper and lower leaves at LPD had light-response curves of photosynthesis of sun leaves, lower leaves at SPD had that of shade leaves. All leaves at both densities had anatomical framework of sun leaves, but the chloroplast content in mesophyll...

Photosynthetic characteristics and growth performance of lettuce (Lactuca sativa L.) under different light/dark cycles in mini plant factories

J. ZHOU, J.Z. WANG, T. HANG, P.P. LI

Photosynthetica 2020, 58(3):740-747 | DOI: 10.32615/ps.2020.013

We investigated the photosynthesis and growth of lettuce (Lactuca sativa L.) grown under three light/dark cycles in a mini plant factory with artificial illumination. A relative longer light cycle [12/12 h (light/dark)] increased not only light-response curve parameters, such as light-saturated net photosynthetic rate, light-saturation point, light-compensation point, dark respiration rate, but also upregulated CO2-response curves parameters, such as CO2-saturated net photosynthetic rate, initial carboxylation efficiency, and photorespiration rate, compared to those of the shorter light cycles [6/6 h and 3/3 h (light/dark)]....

Neodymium improves the activity of ascorbate-glutathione cycle and chloroplast function of wheat seedlings under chromium stress

N.H. LU, L.M. WU, R. YANG, H. LI, C.J. SHAN

Photosynthetica 2020, 58(3):748-754 | DOI: 10.32615/ps.2020.024

We investigated the roles of neodymium trichloride (NdCl3) in regulating ascorbate-glutathione (AsA-GSH) cycle and chloroplast function of chromium (Cr)-stressed wheat seedlings. The findings showed that Cr stress markedly increased malondialdehyde (MDA) content, electrolytic leakage (EL), nonphotochemical quenching, and the activities of enzymes in AsA-GSH cycle, compared with control. However, Cr stress markedly reduced the ratios of reduced ascorbate to dehydroascorbate and reduced glutathione to oxidized glutathione, net photosynthetic rate, the contents of chlorophylls and carotenoids, maximum photochemical efficiency of PSII, photochemical...

Light stability of the isolated CP43 studied by infrared and terahertz spectroscopy

Y.G. QU, X.L. WANG, T.Y. KUANG

Photosynthetica 2020, 58(3):755-761 | DOI: 10.32615/ps.2020.019

Here, the light-induced changes of the core antenna complex chlorophyll protein 43 (CP43) isolated from PSII of spinach were assessed using infrared and terahertz (THz) spectroscopy. We found that the collective vibrational modes at low frequencies and the secondary structures of CP43 were altered upon illumination. The helix changed more than any other secondary structure. CP43 is more easily damaged by illumination than PSII. Infrared and THz spectroscopy have different functions in protein studies. THz spectroscopy has potential in evaluating the stability of proteins.

Paclobutrazol improves leaf carbon-use efficiency by increasing mesophyll conductance rate, while abscisic acid antagonizes this increased rate

L.J. XU, H.X. LIU, J. WU, C.Y. XU

Photosynthetica 2020, 58(3):762-768 | DOI: 10.32615/ps.2020.026

Our experiment was conducted to understand the effects of foliar sprays of paclobutrazol (PBZ), its mixture with abscisic acid (ABA), or water (control) on leaf carbon-use efficiency (CUEl), photosynthesis, and respiration of Euonymus japonicus seedlings. Plants were pot-grown in a greenhouse. The study revealed that elevated stomatal conductance, mesophyll conductance, and maximum rate of Rubisco carboxylation (Vcmax) in plants treated with PBZ could strongly improve net photosynthetic rate (PN). ABA could antagonize the increase of mesophyll conductance and stomatal conductance by PBZ, thereby...

Parameterization of the Farquhar-von Caemmerer-Berry C3 photosynthesis model for oil palm

S.S. CHEAH, C.B.S. TEH

Photosynthetica 2020, 58(3):769-779 | DOI: 10.32615/ps.2020.020

The Farquhar-von Caemmerer-Berry C3 photosynthesis (FvCB) model is used to model photosynthesis of oil palm. However, some model parameters and their temperature dependencies are not known for oil palm. Hence, the aim of this study was to determine the intercellular photocompensation point (Ci*), rate of leaf day respiration in the light (Rd), the chloroplastic photocompensation point (Γ*), mesophyll conductance (gm), maximum rates of Rubisco carboxylation (Vcmax) and electron transport (Jmax), triose phosphate utilization (TPU) and their temperature...

Photosynthetic response and transcriptomic profiling provide insights into the alkali tolerance of clone halophyte Leymus chinensis

H. WANG, Y. XIANG, L.H. LI, N. BHANBHRO, C.W. YANG, Z. ZHANG

Photosynthetica 2020, 58(3):780-789 | DOI: 10.32615/ps.2020.027

Alkali stress is one of the important factors in restricting agriculture production. Leymus chinensis is constructive halophyte species in alkalized grassland in China. In order to investigate the gene expression response of L. chinensis to alkali stress, we used PacBio technology to obtain reference full-length transcript sequences for transcriptomic analysis of alkali stress response. In order to elucidate the alkali tolerance mechanisms of L. chinensis, we measured the photosynthetic parameters, concentrations of ions and compatible solutes, chloroplast ultrastructure and anatomy of control and stressed plants. Our results showed...

Photosynthetic CO2 response to soil water and its simulation using different models in leaves of two species

Q. WU, T. ZHANG, C.R. LI, H.B. XIE, G.C. ZHANG

Photosynthetica 2020, 58(3):790-798 | DOI: 10.32615/ps.2020.023

CO2 concentrations and soil moisture conditions are important factors in photosynthesis of trees. This study investigated the photosynthetic CO2 responses in the leaves of Prunus sibirica L. and Pinus tabulaeformis Carr. under eight soil water conditions in a semiarid loess hilly region. CO2-response curves and physiological parameters were fitted using a rectangular hyperbola model, nonrectangular hyperbola model, exponential equation, and modified rectangular hyperbola model. Results revealed the relative soil water content (RWCs) for P. sibirica required to maintain higher photosynthetic rate...

Can anthocyanin presence ameliorate the photosynthetic performance of Prunus saplings subjected to polyethylene glycol-simulated water stress?

E. LO PICCOLO, M. LANDI, T. GIORDANI, G. LORENZINI, F. MALORGIO, R. MASSAI, C. NALI, E. PELLEGRINI, G. RALLO, D. REMORINI, P. VERNIERI, L. GUIDI

Photosynthetica 2020, 58(3):799-807 | DOI: 10.32615/ps.2020.017

The aim was the evaluation of the biochemical and physiological responses of green- (GP) and red-leafed (RP) Prunus cerasifera mature leaves to 20 d of polyethylene glycol (PEG 6000)-induced water stress in order to elucidate a possible ameliorative role exerted by anthocyanins. At 10 d, the anthocyanin content remained unchanged in RP water-stressed leaves. Photosynthetic rate was lower in GP than that of RP (83.4 vs. 76.5%, respectively), paralleled by a higher degree of photoinhibition (Fv/Fm) in GP leaves. Leaves of GP accounted for higher content of soluble sugars at 10 d, when RP only showed a slight sucrose...

A mixture of trehalose derivatives mitigates the adverse effects of water deficits in maize: an analysis of photosynthetic efficiency

A.S. AMBRÓSIO, J.A.N. PORTUGAL, K.R.D. SOUZA, L.C. SILVA, D.F. DIAS, J.R. MANTOVANI, P.C. MAGALHÃES, T.B. SOUZA, T.C. SOUZA

Photosynthetica 2020, 58(3):808-818 | DOI: 10.32615/ps.2020.031

This study tested a tosylated and azide trehalose derivative mixture for its ability to mitigate water deficit-induced stress in maize via photosynthetic efficiency analyses. The experiment was conducted in greenhouse pots, using a maize hybrid that is sensitive to drought. The mixture of derivatives (28 mM) was applied with a hand sprayer. Plants containing five/six fully expanded leaves were subjected to water deficit stress for 12 d, followed by rehydration. The derivative mixture increased the photosynthetic rate, electron transport rate, and photochemical quenching, and mitigated damage to photosystem II. Moreover, it led to anatomical...

Effect of chitin and chitosan hexamers on growth and photosynthetic characteristics of wheat seedlings

K.C. LI, X.Q. ZHANG, Y. YU, R.E. XING, S. LIU, P.C. LI

Photosynthetica 2020, 58(3):819-826 | DOI: 10.32615/ps.2020.021

In this study, two homogeneous chitin and chitosan hexamers and one partially acetylated chitosan hexamer were used to investigate the degree of acetylation (DA) effects of chitooligosaccharides on the growth and photosynthesis of wheat seedlings. Both chitin and chitosan hexamers showed a significant promoting effect on the growth and photosynthesis of wheat seedlings but the positive effect depended on their DA. The homogeneous chitosan hexamers [(GlcN)6] exhibited the optimal activity compared to other samples. Seven days after (GlcN)6 treatment, the growth parameters of wheat seedlings were all significantly enhanced including...

Photochemical performance and source-sink relationships in galls induced by Pseudophacopteron longicaudatum (Hemiptera) on leaves of Aspidosperma tomentosum (Apocynaceae)

V. MARTINI, A.S.F.P. MOREIRA, V.C. KUSTER, D.C. OLIVEIRA

Photosynthetica 2020, 58(3):827-835 | DOI: 10.32615/ps.2020.033

The establishment of the galling insect generates a biotic stress that leads to tissue transformation. However, galls can maintain chlorophyll (Chl) and consequently photosynthesize. Herein, we evaluated the consequences of the biotic stress generated by the galling insect Pseudophacopteron longicaudatum on photosynthetic rate during the leaf galls development on Aspidosperma tomentosum. In addition, we quantified polysaccharides and water content in order to evaluate the capacity of gall tissues to drain photoassimilates. The non-galled leaves contained more Chl and carotenoids per gram of fresh mass. Galls had lower values of maximum...

Leaf gas exchange, oxidative stress, and physiological attributes of rapeseed (Brassica napus L.) grown under different light-emitting diodes

M.H. SALEEM, M. REHMAN, S. FAHAD, S.A. TUNG, N. IQBAL, A. HASSAN, A. AYUB, M.A. WAHID, S. SHAUKAT, L. LIU, G. DENG

Photosynthetica 2020, 58(3):836-845 | DOI: 10.32615/ps.2020.010

Through its impact on morphogenesis, light is the key environmental factor that alters plant structural development; however, the understanding how light controls plant growth and developmental processes is still poor and needs further research. For this purpose, a Petri dish and pot experiment was conducted to investigate the effects of different LEDs, i.e., white light (WL), red light (RL), blue light (BL), and orange light (OL) on morphology, gas-exchange parameters, and antioxidant capacity of Brassica napus. Compared with WL, RL significantly promoted plant growth and biomass, contents of photosynthetic pigments, and gas-exchange...

Comparison of leaves and stems of Paederia scandens (Lour.) Merr. in tolerance to low temperature

M.L. CAI, Q.L. ZHANG, X.T. ZHENG, J.J. ZHAI, C.L. PENG

Photosynthetica 2020, 58(3):846-852 | DOI: 10.32615/ps.2020.034

Low temperature is an important environmental factor that affects plant growth and development. To determine the adaptability of different organs of Paederia scandens (Lour.) Merr. to low temperature, the chlorophyll (Chl) fluorescence parameters as well as the Chl, malondialdehyde (MDA), soluble sugar, and anthocyanin contents of leaves and stems were measured under low temperature. The results confirmed that the Chl fluorescence parameters and Chl content of the leaves and stems of P. scandens tended to decrease consistently, while the MDA content increased, and the change range of the stems was much lower than that of the leaves. The...

Low pH in simulated acid rain promotes the toxicity of copper on the physiological performance in Sargassum horneri

Z.H. ZHONG, S. QIN, Y. WANG, C. MA, Z.Y. LIU

Photosynthetica 2020, 58(3):853-861 | DOI: 10.32615/ps.2020.035

In order to investigate the interactive effects of simulated acid rain and copper (Cu) on macroalgae, Sargassum horneri was cultured under pH of 8.2, 5.6, 4.5 and Cu concentrations of 0, 25, 100 μg L-1. Under the medium concentration of Cu, moderate pH mitigated the toxicity of Cu on S. horneri, while the low pH and high Cu concentration reduced the contents of chlorophyll (Chl) a and carotenoids. Furthermore, pH had no interaction with Cu on maximal Chl fluorescence or electron transport efficiency, while effective PSII quantum yield, maximum electron transport rate, and saturating irradiance were obviously affected by pH and...

Changes in photosynthetic pigments and chlorophyll fluorescence parameters in the super-high-yielding rice hybrid Peiai64S/E32 during senescence

L.D. ZENG, Q.L. ZHANG, M.L. CAI, W.S. CHOW, C.L. PENG

Photosynthetica 2020, 58(3):862-868 | DOI: 10.32615/ps.2020.037

The hybrid rice (Oryza sativa L.) cultivar Peiai64S/E32, which is a hybrid of E32 and Peiai64S, has a super high yield compared with that of its parents. Changes in photosynthetic pigments and chlorophyll (Chl) fluorescence parameters were investigated in the flag leaves during senescence. The content of Chl and carotenoids in the flag leaves of Peiai64S/E32 was more stable than those of their parents during senescence. Furthermore, Peiai64S/E32 had a more stable PSII activity and a lower nonphotochemical quenching and deepoxidation state than that of its parents in the later stage of senescence. These results demonstrated that Peiai64S/E32...

Estimation of total nitrogen content in sugar beet leaves based on chlorophyll fluorescence parameters

C. FEI, H. FAN, X.X. FAN, G. XU

Photosynthetica 2020, 58(3):869-872 | DOI: 10.32615/ps.2020.036

Two sugar beet cultivars, Beta 356 and KWS9147, were grown in field trials at four different nitrogen contents (0, 75, 150, and 225 kg ha-1), and each fertilizer treatment was divided into four applications (100% prior to seeding; 70% prior to seeding and 30% at canopy development; 50% prior to seeding and 50% at canopy development; 30% prior to seeding and 70% at canopy development) in two consecutive growing seasons. Leaf chlorophyll fluorescence (ChlF) parameters and leaf nitrogen content were measured simultaneously at different growth stages, establishing an evaluation model of leaf nitrogen nutrition. The results showed that the correlation...

Leaf gas exchange and growth of Capsicum annuum var. glabriusculum under conditions of flooding and water deficit

E. MARTÍNEZ-ACOSTA, L.C. LAGUNES-ESPINOZA, M. CASTELÁN-ESTRADA, F. LARA-VIVEROS, C. TREJO

Photosynthetica 2020, 58(3):873-880 | DOI: 10.32615/ps.2020.032

Growth and gas-exchange traits of Capsicum annuum var. glabriusculum under flooding and water deficit (WD) stress were measured in a greenhouse experiment. Flooding was applied to a group of plants for 0 (control), 5, and 10 d, and WD to another set at 100 (control field capacity), 70, 50, and 25% of the water applied to control. Flooding negatively affected stomatal conductance, photosynthetic and transpiration rate from 20 d after transplanting (DAT), with a significant decrease in biomass at 120 DAT. WD at 70, 50, and 25% severely affected the plant aerial and root biomass and the gas-exchange traits from 80 DAT, inhibiting both flowering...

Effects of light intensity on the growth, photosynthetic characteristics, and secondary metabolites of Eleutherococcus senticosus Harms

M.Y. XU, K.X. WU, Y. LIU, J. LIU, Z.H. TANG

Photosynthetica 2020, 58(3):881-889 | DOI: 10.32615/ps.2020.045

In this investigation, we used the growth, photosynthetic physiological parameters, and targeted metabolite analysis to evaluate the responses of Eleutherococcus senticosus in different shading treatments. The results showed that the moderate shading treatment (Z1) promoted the growth and inhibited photosynthesis of plants. The severe shading treatment (Z2)inhibited both the growth and photosynthesis of the plants. Besides, Z1 had no significant effect on the PSII, while Z2 inhibited the PSII. Most of the eight medicinal metabolites accumulated in the Z1. The C6C1-...