Photosynthetica - Latest articles

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Tolerance to photoinhibition within lichen species is higher in melanised thalli

T.C. MAFOLE, K.A. SOLHAUG, F.V. MINIBAYEVA, R.P. BECKETT

Photosynthetica 2019, 57(1):96-102 | DOI: 10.32615/ps.2019.008

Some lichenized ascomycetes synthesize melanic pigments when exposed to ultraviolet light and high solar radiation. Here, we used chlorophyll fluorescence in order to test the effect of melanisation on the ability of the lichens Cetraria islandica, Lobaria pulmonaria, Peltigera aphthosa, P. membranacea, Pseudocyphellaria gilva, and Sticta sublimbata to tolerate high-light stress. For each species, melanised and pale thalli were selected from relatively exposed and shaded individuals of the same population. For all species, melanised thalli displayed significantly less photoinhibition than pale thalli following...

Role of arbuscular mycorrhiza in alleviating the effect of cold on the photosynthesis of cucumber seedlings

J. MA, M. JANOUŠKOVÁ, L. YE, L.Q. BAI, R.R. DONG, Y. YAN, X.C. YU, Z.R. ZOU, Y.S. LI, C.X. HE

Photosynthetica 2019, 57(1):86-95 | DOI: 10.32615/ps.2019.001

Arbuscular mycorrhiza (AM) is known to enhance the rate of photosynthesis in plants, but there is little information on whether this effect is maintained at low temperature when the development of AM fungi is restrained. We therefore investigated the influence of AM on gas exchange, PSII fluorescence, and some photosynthesis-related biochemical parameters in cucumber seedlings under cold stress. Cold stress decreased, as expected, the chlorophyll content, net photosynthetic rate, and parameters related to photochemical quenching, while increasing nonphotochemical quenching and sugar contents in leaves. In contrast, AM had opposite effects on most of...

Leaf photosynthesis of three typical plant species affected by the subsidence cracks of coal mining: a case study in the semiarid region of Western China

Y. LIU, S.G. LEI, L.S. CHENG, W. CHENG, J.B. XIONG, Z.F. BIAN

Photosynthetica 2019, 57(1):75-85 | DOI: 10.32615/ps.2019.020

Increased attention has been paid to effects of coal mining subsidence on the growth of plants. Studying the changes of plants photosynthetic physiology under the disturbance of coal mining subsidence is the basis for understanding dynamic exchanges of plant energy and water at that mining area. The 52302 working face of the Shendong mining area was selected as the experimental site, with Artemisia ordosica, Caragana korshinskii, and Populus spp. as the research targets. Changes in leaf photosynthesis were monitored in plants at a subsidence crack area. We showed collapse cracks decreased soil moisture and caused drought stress....

Photosystem photochemistry, prompt and delayed fluorescence, photosynthetic responses and electron flow in tobacco under drought and salt stress

K. KHATRI, M.S. RATHORE

Photosynthetica 2019, 57(1):61-74 | DOI: 10.32615/ps.2019.028

The present study aimed to understand the photosynthetic responses and chlorophyll fluorescence transient in tobacco under drought and salt stress. Net CO₂ assimilation rate, stomatal conductance, intercellular CO₂ concentration and transpiration rate decreased significantly under drought and salt stress. The maximum quantum efficiency of PSII and electron transport rate were lower in tobacco under drought and salt stress. The maximum carboxylation rate, maximum electron transport rate, triosephosphate utilization efficiency, and mesophyll conductance decreased under drought and salt stress, while dark respiration increased. A...

Characterization of Oryza nivara introgression lines: A potential prebreeding resource to improve net photosynthetic rate in elite cultivars of rice

G. HARITHA, T. VISHNUKIRAN, Y. VENKATESWARA RAO, CH. GOWTHAMI, B. DIVYA, N. SARLA, D. SUBRAHMANYAM

Photosynthetica 2019, 57(1):47-60 | DOI: 10.32615/ps.2019.003

Photosynthesis is one of the fundamental processes influencing crop growth and productivity. In order to understand better the basis of variation in net photosynthetic rate (P_N) and yield potential in rice, two backcross populations derived from Swarna × O. nivara were studied. Gas exchange and chlorophyll fluorescence measurements were taken at flowering stage and data on yield traits at harvest. P_N was significantly correlated with stomatal conductance, transpiration rate, mesophyll conductance, carboxylation efficiency, yield per plant (YLDP), and dry mass in both populations. Ten introgression lines (ILs)...

Diurnal changes in the delayed fluorescence response of an ambient light-excited green alga

W. ECKERT, F. LEUNERT, Y.Z. YACOBI, J. KÖHLER, E. KURZBAUM

Photosynthetica 2019, 57(1):40-46 | DOI: 10.32615/ps.2019.012

Delayed fluorescence (DF) is a characteristic feature of light-excited plant cells caused by the back-reaction of electrons through the electron transport chain. Targeting the response of light-adapted green algae to diurnal light changes, the present study presents novel results of DF measurements in the absence of an artificial excitation light source. Based on a linear relationship between the DF counts and light intensities from 0.15 to 0.65 W m^-2 during daybreak, we estimated an initial algal response to light intensities of 0.01 W m^-2. Dissolved oxygen concentrations began to increase at 1.0 W m^-2. A noon depression...

Effect of soil salinity on growth, metal distribution and photosynthetic performance of two Lycium species

V.L. DIMITROVA, M.M. PAUNOV, V. GOLTSEV, M.P. GENEVA, Y.K. MARKOVSKA

Photosynthetica 2019, 57(1):32-39 | DOI: 10.32615/ps.2019.006

The effect of salinity on gas exchange and fluorescence characteristics in Lycium barbarum and Lycium chinense grown on nonsaline and saline soils was investigated. The distribution of Na⁺ between three types of substrates and different organs showed acropetal concentration gradient for Na⁺ accumulation only in L. barbarum grown on peat-moss-perlite and saline soil. Selective uptake of K⁺ over Na⁺ in the L. barbarum leaves was established. All plants grown on saline soil showed a slight inhibition of PSII activity as revealed by the quantum yield of the primary...

Effects of lanthanum on the antioxidant capacity of chloroplasts and chlorophyll fluorescence parameters of maize seedlings under chromium stress

H. DAI, C. SHAN

Photosynthetica 2019, 57(1):27-31 | DOI: 10.32615/ps.2019.015

Effects of lanthanum chloride (LaCl₃) on chromium tolerance of maize were investigated at chloroplast level. The results showed that Cr stress significantly increased activities of ascorbate peroxidase, glutathione reductase, monodehydro-ascorbate reductase, dehydroascorbate reductase, superoxide dismutase, and glutathione peroxidase, nonphotochemical quenching, malondialdehyde (MDA) and hydrogen peroxide contents, but significantly reduced the ratios of reduced ascorbate to dehydroascorbate and reduced glutathione to oxidized glutathione, the contents of chlorophyll and carotenoids, maximum photochemical efficiency of PSII, photochemical...

Leaf nitrogen supply improves sugarcane photosynthesis under low temperature

G. CERQUEIRA, M.C. SANTOS, P.E.R. MARCHIORI, N.M. SILVEIRA, E.C. MACHADO, R.V. RIBEIRO

Photosynthetica 2019, 57(1):18-26 | DOI: 10.32615/ps.2019.033

This study aimed to test the hypothesis that increases in leaf nitrogen concentration would reduce the sensitivity of sugarcane photosynthesis to low temperature. IACSP95-5000 plants were grown inside a growth chamber at 30/20^oC (day/night) and we evaluated the effects of leaf nitrogen spraying (2.5% urea) on plants facing low temperature (22/12°C) for eight days. The leaf nitrogen supply increased leaf nitrogen concentration and plants exhibited higher leaf gas exchange as compared to nonsprayed ones. We also found higher activity of the carboxylation enzymes, Rubisco and phosphoenolpyruvate carboxylase, as well as a higher chlorophyll...

Photosynthetic and yield performance of wild barley (Hordeum vulgare ssp. spontaneum) under terminal heat stress

F. BAHRAMI, A. ARZANI, M. RAHIMMALEK

Photosynthetica 2019, 57(1):9-17 | DOI: 10.32615/ps.2019.009

Terminal heat stress is one of the major constraints of cereal production. A two-year field investigation was performed to assess the response of Hordeum vulgare ssp. spontaneum genotypes to terminal heat stress using gas-exchange parameters, photosystem efficiency, proline accumulation, cell membrane leakage, and grain yield traits. Results of analysis of variance revealed the significant effects of heat stress (E), genotype (G), and G × E on the studied traits. The results of linear regression analysis showed that yield loss was inversely correlated with the maximum quantum yield of PSII photochemistry (F_v/F_m)...

Smoke compounds aggravate stress inflicted on Brassica seedlings by unfavourable soil conditions

R. BĄCZEK-KWINTA, J. ANTONKIEWICZ, A. ŁOPATA-STASIAK, W. KĘPKA

Photosynthetica 2019, 57(1):1-8 | DOI: 10.32615/ps.2019.026

The aim of the study was to assess the physiological status of Brassica seedlings grown in two types of soils following a single application of smoke water (SW). One soil was contaminated with heavy metals from a local smelter, and another was sandy and poor in nutrients. Three-week monitoring indicated that soil composition was the primary factor affecting chlorophyll fluorescence (CF) parameters, growth, and development of seedlings, and the contaminants affected the plants more than the lack of nutrients. SW aggravated the negative impact of heavy metals, which became visible when the plants transiently suffered from the heavy metal exposure....

Effects of endogenous ascorbic acid on resistance to high-temperature stress in excised rice leaves

Q.L. Zhang, Y.X. Wei, C.L. Peng

Photosynthetica 2018, 56(4):1453-1458 | DOI: 10.1007/s11099-018-0836-2

Ascorbic acid (Asc) is a major plant antioxidant. L-galactono-1,4-lactone dehydrogenase (GLDH) is an enzyme that catalyzes the last step of Asc biosynthesis in higher plants. Effects of endogenous Asc on resistance to high-temperature stress were studied by using GLDH-overexpressed (GO-2) and GLDH-suppressed transgenic rice (GI-2) as experimental materials. After high-temperature treatment, the maximal quantum yield of PSII was significantly lower in GI-2, and higher in GO-2 compared to wild type rice. The content of reactive oxygen species (ROS) was the highest in GI-2. The higher Asc content resulted in lower lipid peroxidation in GO-2. The contents...

A method of a bicolor fast-Fourier pulse-amplitude modulation chlorophyll fluorometry

V. Lysenko, D. Lazár, T. Varduny

Photosynthetica 2018, 56(4):1447-1452 | DOI: 10.1007/s11099-018-0848-y

A simple method of a bicolor (multicolor), fast-Fourier, PAM chlorophyll fluorometry has been developed to obtain fluorescence induction curves. Quantum yields of PSII photochemistry were determined with blue and red simultaneously applied pulsed measuring lights for three subsequent 20-min periods of dark-, light-adaptation under actinic light and dark recovery. Measuring lights were cross-combined with blue and red actinic lights and saturation pulses. Coefficients of chromatic divergence were calculated as a ratio of the quantum yields obtained by red measuring light to that obtained by blue measuring light. Adaptation of Ficus benjamina...

Responses of photosynthesis, dry mass and carbon isotope discrimination in winter wheat to different irrigation depths

L. J. Zheng, J. J. Ma, X. H. Sun, X. H. Guo, J. Jiang, R. Ren, X. L. Zhang

Photosynthetica 2018, 56(4):1437-1446 | DOI: 10.1007/s11099-018-0833-5

In order to test the effects of irrigation depth on winter wheat photosynthesis, four treatments were applied in a field experiment using PVC growth tubes (identical amounts of water were applied on the land surface, and at 60, 75, and 90% of the depth for the winter wheat root distribution, denoted as D0, D60, D75, and D90, respectively). Compared to the surface irrigation treatment D0, the leaf area index, chlorophyll content, net photosynthetic rate, transpiration rate, stomatal conductance, and intercellular CO₂ concentration increased with irrigation depths. The values of these indicators obtained by the underground irrigation treatment...

Effects of leaf-to-fruit ratio on chlorophyll fluorescence parameters of walnut (Juglans regia L.) leaves

C. F. Zhang, C. D. Pan, H. Chen

Photosynthetica 2018, 56(4):1429-1436 | DOI: 10.1007/s11099-018-0842-4

In this study, we investigated maximal quantum yield of PSII photochemistry(F_v/F_m),effective quantum yield of PSII photochemistry (Φ_PSII), and nonphotochemical quenching (NPQ) of walnut (Juglans regia 'Xinxin2') leaves with different leaf-to-fruit ratios (LFRs). The results indicated that the increasing LFR increased the values of F_v/F_m, Φ_PSII, and NPQ in leaves on the girdled shoot with one and two leaves, and decreased the values of F_v/F_m and Φ_PSII in leaves on the girdled shoot with five leaves, whereas had no effect on the chlorophyll...

Bioaccumulation and photosynthetic activity response of sweet sorghum seedling (Sorghum bicolor L. Moench) to cadmium stress

Z. C. Xue, J. H. Li, D. S. Li, S. Z. Li, C. D. Jiang, L. A. Liu, S. Y. Wang, W. J. Kang

Photosynthetica 2018, 56(4):1422-1428 | DOI: 10.1007/s11099-018-0835-3

A hydroponic experiment was conducted to investigate bioaccumulation and photosynthetic activity response to Cd in sweet sorghum seedlings. The seedlings were treated with 0, 50, and 100 μM Cd for 15 d. Our results showed that morphological characteristics of sweet sorghum were significantly affected by Cd treatments. The Cd concentrations in roots and shoots increased with increasing Cd concentrations in the nutrition solution; higher Cd accumulation was observed in the roots. Meanwhile, the photosynthetic activity decreased significantly and a shape of chlorophyll (Chl) a fluorescence transient in leaves was altered by Cd treatments. The...

Leaf gas exchange, phosphorus uptake, growth and yield responses of cotton cultivars to different phosphorus rates

J. Wang, Y. Chen, P. Wang, Y. S. Li, G. Wang, P. Liu, A. Khan

Photosynthetica 2018, 56(4):1414-1421 | DOI: 10.1007/s11099-018-0845-1

Growth and physiological responses of cotton (Gossypium hirsutum L.) cultivars with different phosphorus (P) efficiencies under variable P environment are poorly known. Therefore, this study explored effects of normal P [P⁺, 70 kg(P₂O₅) ha^-1] and without P (P^-, 0 kg ha^-1) on yield, growth, and physiology of different P-efficient cultivars [low-efficient Xinluzao 13 (L1) and Xinluzao 26 (L₂); medium-efficient Xinluzao 10 (M₁) and Xinluzao 24 (M₂); high-efficient Zhongmiansuo 42 (H₁) and Xinluzao19 (H₂)]. Cotton growth and yield...

Seasonal variation in photosynthesis performance of cassava at two different growth stages under irrigated and rain-fed conditions in a tropical savanna climate

K. Vongcharoen, S. Santanoo, P. Banterng, S. Jogloy, N. Vorasoot, P. Theerakulpisut

Photosynthetica 2018, 56(4):1398-1413 | DOI: 10.1007/s11099-018-0849-x

Seasonal variations in photosynthesis of cassava cv. Rayong 9 (RY9) under irrigated and rain-fed conditions were evaluated at the age of three and six months after planting (MAP). Photosynthetic light-response (P_N/I) curves revealed that cassava leaves attained the highest maximum net photosynthetic rates (P_Nmax) in the rainy season, followed by the hot one, while the lowest P_Nmax was found in the cool season. Photosynthetic potential of the 3-month-old plants was mostly higher than that of the 6-month-old plants, and the seasonal variation in photosynthetic capacity was also more apparent...

Leaf gas exchange and grain yield of common bean exposed to spermidine under water stress

S. Torabian, M. R. Shakiba, A. Dabbagh Mohammadi Nasab, M. Toorchi

Photosynthetica 2018, 56(4):1387-1397 | DOI: 10.1007/s11099-018-0834-4

Three prevalent aliphatic polyamines (PAs) include putrescine, spermidine, and spermine; they are low-molecular-mass polycations involved in many physiological processes in plants, especially, under stressful conditions. In this experiment, three bean (Phaseolus vulgaris L.) genotypes were subjected to well-watered conditions and two moderate and severe water-stressed conditions with and without spermidine foliar application. Water stress reduced leaf relative water content (RWC), chlorophyll contents, stomatal conductance (gs), intercellular CO₂ concentration (C_i), transpiration rate, maximal quantum yield...

Foliar exposure of grapevine (Vitis vinifera L.) to TiO₂ nanoparticles under field conditions: Photosynthetic response and flavonol profile

P. Teszlák, M. Kocsis, A. Scarpellini, G. Jakab, L. Kőrösi

Photosynthetica 2018, 56(4):1378-1386 | DOI: 10.1007/s11099-018-0832-6

In the past decade, utilization of nanostructured materials has increased intensively in a wide range of applications. Titanium dioxide nanoparticles (TiO₂ NPs), for instance, can be applied for the inactivation of various pathogens through photo-induced generation of reactive oxygen species. Although TiO₂ NPs with high antimicrobial activity are of great importance, in practice, their phytotoxic effects have not yet been fully clarified. In this study, we investigated the potential phytotoxicity of TiO₂ NPs on grapevine (Vitis vinifera L.) under field conditions. After foliar exposure, two particularly stress-sensitive...

Salicylic acid-induced photosynthetic adaptability of Zea mays L. to polyethylene glycol-simulated water deficit is associated with nitric oxide signaling

R. X. Shao, L. F. Xin, J. M. Guo, H. F. Zheng, J. Mao, X.P. Han, L. Jia, S. J. Jia, C. G. Du, R. Song, Q. H. Yang, R. W. Elmore

Photosynthetica 2018, 56(4):1370-1377 | DOI: 10.1007/s11099-018-0850-4

Salicylic acid (SA) and nitric oxide (NO) form a new group of plant growth substances that cooperatively interact to promote plant growth and productivity. Water deficit (WD) stress is a major limiting factor for photosynthesis, which in turn limits crop yield. However, the mechanism of SA and NO in stimulating photosynthesis has not yet been elucidated. Therefore, in this study, we investigated the SA- and NO-mediated photosynthetic adaptability of maize seedlings to WD in terms of photosynthetic parameters, activities and mRNA levels of CO₂ assimilation enzymes. Our results showed that SA alleviated the WD-induced reduction of photosynthetic...

Viscosimetric analysis of the mechanism of ATP hydrolysis by pea chloroplast F₁-ATPase

A.N. Malyan

Photosynthetica 2018, 56(4):1365-1369 | DOI: 10.1007/s11099-018-0840-6

Dependence of ATP hydrolysis kinetics by the chloroplast coupling factor (CF₁) on medium viscosity was studied at varying temperatures. For samples with oxidized and reduced CF₁ γ-subunit, this dependence was shown to be described by Cramers' relationship k ~ (η/η_o)-n, where k is the reaction rate constant, η/η_o is the medium/water viscosity ratio, and 0 < n < 1. Transition of the γ-subunit from its reduced to oxidized state was accompanied by increasing n value, which is indicative of increasing friction losses between certain enzyme sections...

Morphological and ecophysiological plasticity in dioecious plant Populus tomentosa under drought and alkaline stresses

Y. W. Lu, X. L. Miao, Q. Y. Song, S. M. Peng, B. L. Duan

Photosynthetica 2018, 56(4):1353-1364 | DOI: 10.1007/s11099-018-0846-0

Morphological and ecophysiological traits showed by male and female Populus tomentosa Carr. trees were studied under various degrees of water and alkaline stresses. The results showed that different adaptations to drought and alkaline stresses were adopted by each gender; males possessed a much higher tolerance to both stresses compared to females. In contrast to females, the males exhibited a lower inhibition in total biomass, total leaf area, net photosynthetic rate, stomatal conductance, leaf carbon and nitrogen concentrations as well as water- and nitrogen-use efficiency in response to drought and alkaline stresses. Nevertheless, compared...

Cadmium stress in Dongying wild soybean seedlings: growth, Cd accumulation, and photosynthesis

L. Liu, Y. K. Shang, L. Li, Y. H. Chen, Z. Z. Qin, L. J. Zhou, M. Yuan, C. B. Ding, J. Liu, Y. Huang, R. W. Yang, Y. H. Zhou, J. Q. Liao

Photosynthetica 2018, 56(4):1346-1352 | DOI: 10.1007/s11099-018-0844-2

In order to understand better Cd resistance in soybean, Dongying wild soybean treated with different Cd concentrations were evaluated. The biomass, chlorophyll (Chl) content, leaf color, Chl a fluorescence parameters, photosynthesis parameters, and Cd contents were determined. Our results showed that when Cd concentration was ≤ 2 kg m^-3, no significant decrease in biomass, photosynthetic parameters, and maximal photochemical efficiency of PSII was observed. This indicated that Dongying wild soybean resisted Cd toxic effects under such conditions. In addition, atomic absorption experiment results demonstrated that when Cd concentration...

Soil Cu contamination destroys the photosynthetic systems and hampers the growth of green vegetables

M.-Z. Lin, M.-F. Jin

Photosynthetica 2018, 56(4):1336-1345 | DOI: 10.1007/s11099-018-0831-7

Soil metal contamination leads to a decrease in a yield of crops and is a threat to human health. In the present study, the properties (i.e., photosynthetic pigments, gas-exchange parameters, chlorophyll fluorescence, biomass, leaf area, leaf mass per area) of three green vegetables (i.e., Brassica chinensis, Chrysanthemum coronarium, Brassica alboglabra) grown under various Cu treatments [0, 200, 400, and 600 mg(Cu) kg^-1] were measured and analysed. The results showed that soil Cu contamination resulted in the damage of photosynthetic pigments, negative effects on gas exchange, and hampered growth of all...

Coordinated variation between veins and stomata in cotton and its relationship with water-use efficiency under drought stress

Z. Y. Lei, J. M. Han, X. P. Yi, W. F. Zhang, Y. L. Zhang

Photosynthetica 2018, 56(4):1326-1335 | DOI: 10.1007/s11099-018-0847-z

Drought stress causes changes in vein and stomatal density. The objectives of this study were to determine (1) if the changes in vein and stomatal density are coordinated in cotton (Gossypium hirsutum L.) and (2) how these changes affect water-use efficiency (WUE). The results showed significant positive correlations between vein density and stomatal density when cotton was grown under different degrees of drought stress. WUE was significantly positively correlated with the densities of both veins and stomata. Stomatal pore area and stomatal density on the abaxial leaf side, but not the adaxial side, were significantly correlated...

Effects of foliar applications of nitric oxide and spermidine on chlorophyll fluorescence, photosynthesis and antioxidant enzyme activities of citrus seedlings under salinity stress

D. Khoshbakht, M. R. Asghari, M. Haghighi

Photosynthetica 2018, 56(4):1313-1325 | DOI: 10.1007/s11099-018-0839-z

The effects of exogenous sodium nitroprusside (SNP), as nitric oxide donor, and spermidine (Spd) on growth and photosynthetic characteristics of Bakraii seedlings (Citrus reticulata × Citrus limetta) were studied under NaCl stress. In citrus plants, SNP- and Spd-induced growth improvement was found to be associated with reduced electrolyte leakage, malondialdehyde, hydrogen peroxide content, and leaf Na⁺ and Cl^- concentration. However, we found increased leaf Ca²⁺, Mg²⁺, and K⁺ concentrations, relative water content, chlorophyll fluorescence parameters, antioxidant enzyme activities,...

Changes in winter snow depth affects photosynthesis and physiological characteristics of biological soil crusts in the Tengger Desert

R. Hui, R. M. Zhao, L. C. Liu, Y. X. Li, H. T. Yang, Y. L. Wang, M. Xie, X. Q. Wang

Photosynthetica 2018, 56(4):1304-1312 | DOI: 10.1007/s11099-018-0838-0

Water availability is a major limiting factor in desert ecosystems. However, a winter snowfall role in the growth of biological soil crusts is still less investigated. Here, four snow treatments were designed to evaluate the effects of snow depth on photosynthesis and physiological characteristics of biological soil crusts. Results showed that snow strongly affected the chlorophyll fluorescence properties. The increased snow depth led to increased contents of photosynthetic pigments and soluble proteins. However, all biological soil crusts also exhibited a decline in malondialdehyde and soluble sugar contents as snow increased. Results demonstrated...

Role of alternative oxidase pathway in protection against drought-induced photoinhibition in pepper leaves

W. H. Hu, X. H. Yan, Y. He, X. L. Ye

Photosynthetica 2018, 56(4):1297-1303 | DOI: 10.1007/s11099-018-0837-1

The aim of this study was to assess the impact of the mitochondrial alternative oxidase (AOX) pathway on energy metabolism in chloroplasts, and evaluate the importance of the AOX in alleviating drought-induced photoinhibition in pepper (Capsicum annuum L.). Inhibition of AOX pathway decreased photosynthesis and increased thermal energy dissipation in plants under normal conditions. It indicated that AOX pathway could influence chloroplast energy metabolism. Drought reduced carbon assimilation. Photoinhibition was caused by excess of absorbed light energy in spite of the increase of thermal energy dissipation and cyclic electron flow around PSI...

Chlorophyll fluorescence, yield and yield components of bread wheat affected by phosphate bio-fertilizer, zinc and boron under late-season heat stress

H. R. Eisvand, H. Kamaei, F. Nazarian

Photosynthetica 2018, 56(4):1287-1296 | DOI: 10.1007/s11099-018-0829-1

We examined effects of late-season heat stress (L-SHS) on chlorophyll (Chl) fluorescence parameters and yield of bread wheat as well as roles of phosphate bio-fertilizer (PB-F) and Zn and B to compensate for the likely effects of heat stress. Factors were planting date (21 November and 5 January to coincide with grain filling to L-SHS) as the main factor, no inoculation (control) and inoculation of the seeds with PB-F as the sub-factor, and foliar application of water (control), Zn, B, and Zn + B as 3 L ha^-1 as sub-sub factor. Results revealed that L-SHS reduced maximal quantum yield of PSII photochemistry, effective quantum yield of PSII...