Effects of temperature and irradiance on quantum yield of PSII photochemistry and xanthophyll cycle in a tropical and a temperate species

It is commonly believed that the structure of phytoplankton and the formation of cyanobacterial and algal blooms may be explained by allelopathic interactions. The main aim of this study was to investigate the allelopathic effect of picocyanobacterium Synechococcus sp. on the following growth and fluorescence parameters: the maximum quantum yield of PSII photochemistry (Fv/Fm), and the effective quantum yield of PSII photochemistry (ΦPSII) of selected diatoms – Nitzschia fonticola, Fistulifera saprophila, Navicula perminuta and Amphora coffeaeformis. In this study, it was demonstrated that picocyanobacterium caused allelopathic effects against Baltic diatoms. The results showed that the addition of cell-free filtrate from Synechococcus sp. increased the number of cells of N. fonticola and F. saprophila. Moreover, it was found that picocyanobacterium was stimulated fluorescence parameters of N. fonticola, F. saprophila, and N. perminuta. On the other hand, it was noted that filtrate obtained from picocyanobacterium caused the inhibition of Fv/Fm parameter of A. coffeaeformis. The results of this experiment may provide further information about allelopathic interactions between Baltic picocyanobacteria and diatoms that are crucial to the understanding of algal blooms in aquatic ecosystems.

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Photoinhibition of Photosynthesis in situ in Six Species of Eucalyptus

Functional Plant Biology ◽

10.1071/pp9920223 ◽

1992 ◽

Vol 19 (3) ◽

pp. 223 ◽

Cited By ~ 26

Author(s):

E Ogren ◽

JR Evans

Keyword(s):

Quantum Yield ◽

Time Course ◽

O2 Evolution ◽

Photoinhibition Of Photosynthesis ◽

Low Light ◽

First Order ◽

Psii Photochemistry ◽

Kinetics Of ◽

Quantum Yield Of Psii

Photoinhibition of photosynthesis was investigated in horizontally and vertically restrained leaves of Eucalyptus plants growing outdoors. This was done by measuring the quantum yield of PSII photochemistry, assayed by the ratio of variable to maximal fluorescence (FV/FM) after 15 min of dark adaptation, and the quantum yield of O2 evolution. On clear days, a time-dependent depression in both parameters was observed. Though horizontal leaves showed stronger photoinhibition (max. 40%) than did vertical leaves (max. 30%), this difference was smaller than the threefold difference in light interception. Since the inherent susceptibility to photoinhibition was the same in vertical and horizontal leaves, a non-linear light dependence of photoinhibition was assumed. The time course of recovery from photoinhibition under low light followed the kinetics of a first order reaction, with 50% recovery after 45 min. When watering was restricted on a hot and clear day a more severe photoinhibition developed in horizontal leaves, which took several days of low light to overcome. This photoinhibition state was triggered by high leaf temperatures, resulting from decreased stomatal conductance and transpiration, which sensitised the leaf to light.

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Seasonal Variation in Diurnal Photosynthesis and Chlorophyll Fluorescence of Four Genotypes of Cassava (Manihot esculenta Crantz) under Irrigation Conditions in a Tropical Savanna Climate

Agronomy ◽

10.3390/agronomy9040206 ◽

2019 ◽

Vol 9 (4) ◽

pp. 206 ◽

Cited By ~ 4

Author(s):

Supranee Santanoo ◽

Kochaphan Vongcharoen ◽

Poramate Banterng ◽

Nimitr Vorasoot ◽

Sanun Jogloy ◽

...

Keyword(s):

Chlorophyll Fluorescence ◽

Quantum Yield ◽

Rainy Season ◽

Genotypic Variation ◽

Effective Quantum Yield ◽

Tropical Savanna ◽

Psii Photochemistry ◽

Diurnal Photosynthesis ◽

Hot Season ◽

Quantum Yield Of Psii

Photosynthesis performance during early vegetative growth is an important physiological trait determining yield of cassava, but limited information is currently available for the tropical savanna climate of Asia. Diurnal photosynthesis and chlorophyll fluorescence of the three-month-old plants of four commercial cassava genotypes (Rayong 9, RY9; Rayong 11, RY11; Kasetsart 50, KU50 and CMR38-125-77) grown under irrigation, were investigated in three seasons i.e., rainy, cool and hot. The mean daily net photosynthetic rate (Pn) across genotypes in the rainy season (11.75 µmolCO2/m2/s) was significantly lower than that in the cool season (14.60 µmolCO2/m2/s). Daily mean Pn in the hot season was 14.32 µmolCO2/m2/s. In the rainy season, maximum photochemical quantum yield of PSII (Fv/Fm) and effective quantum yield of PSII photochemistry (ΦPSII) were significantly higher than the other seasons, while electron transfer rate (ETR) and non-photochemical quenching (NPQ) were significantly lower. Genotypic variation was observed during the hot season in which RY11 had the highest and CMR38-125-77 the lowest mean daily Pn. The prominent mechanism to avoid damages from stress during afternoon in the hot season was to reduce leaf temperature by enhancing transpiration for RY11; to close stomata early for RY9, and to increase NPQ for CMR38-125-77.

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Physiological, morphological and anatomical leaf traits variation across leaf development in 'Corylus avellana'

Mediterranean Botany ◽

10.5209/mbot.62325 ◽

2019 ◽

Vol 40 (2) ◽

pp. 185-192 ◽

Cited By ~ 1

Author(s):

Rosangela Catoni ◽

Francesco Bracco ◽

Loretta Gratani ◽

Mirko Umberto Granata

Keyword(s):

Quantum Yield ◽

Leaf Development ◽

Leaf Traits ◽

Corylus Avellana ◽

Leaf Mass Per Area ◽

Second Phase ◽

Effective Quantum Yield ◽

Maximum Quantum Yield ◽

Psii Photochemistry ◽

Quantum Yield Of Psii

The study analyzed the variations of physiological, morphological and anatomical leaf traits during its development in Corylus avellana L. saplings. Three different phases were identify during leaf development: the first phase (hereafter IP) considered in the developing leaves, the second phase (IIP) in the mature green leaves and the third phase (IIIP) in the senescent leaves. In particular, variations in parameters estimated from the photosynthetic light response curves, in chlorophyll fluorescence variables and in morphological leaf traits were analyzed during the three phases. The principal component analysis (PCA) carried out using all the considered morphological characters (leaf mass per area - LMA, and leaf tissue density - LTD) and physiological traits (the maximum net photosynthetic rates - ANmax, dark respiration rates - RD, light compensation point - LCP, light saturation point – LSP, maximum quantum yield - ɸmax, fluorescence-based maximum quantum yield of PSII photochemistry - Fv/FM and effective quantum yield of PSII photochemistry - ɸPSII) showed a complete separation among the considered phases. The results showed that the major differences occur between the phases IP and IIP. In particular, a greater variation was found for LMA, ANmax, RD. On the contrary a lower variation was observed for ɸmax which remain quite constant from IP to IIP indicating that chloroplasts present in juvenile leaves are fully functional.

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Diurnal response of effective quantum yield of PSII photochemistry to irradiance as an indicator of photosynthetic acclimation to stressed environments revealed in a xerophytic species

Ecological Indicators ◽

10.1016/j.ecolind.2016.11.027 ◽

2017 ◽

Vol 74 ◽

pp. 191-197 ◽

Cited By ~ 9

Author(s):

Tian-Shan Zha ◽

Ya Juan Wu ◽

Xin Jia ◽

Ming Yan Zhang ◽

Yu Jie Bai ◽

...

Keyword(s):

Quantum Yield ◽

Photosynthetic Acclimation ◽

Effective Quantum Yield ◽

Psii Photochemistry ◽

Quantum Yield Of Psii

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Thermostability and Photostability of Photosystem II of the Resurrection Plant Haberlea rhodopensis Studied by Chlorophyll Fluorescence

Zeitschrift für Naturforschung C ◽

10.1515/znc-2006-3-413 ◽

2006 ◽

Vol 61 (3-4) ◽

pp. 234-240 ◽

Cited By ~ 11

Author(s):

Katya Georgieva ◽

Liliana Maslenkova

Keyword(s):

Chlorophyll Fluorescence ◽

Electron Transport ◽

Quantum Yield ◽

Photochemical Efficiency ◽

Resurrection Plant ◽

Haberlea Rhodopensis ◽

Photochemical Efficiency Of Psii ◽

Light Intensities ◽

Psii Photochemistry ◽

Quantum Yield Of Psii

The stability of PSII in leaves of the resurrection plant Haberlea rhodopensis to high temperature and high light intensities was studied by means of chlorophyll fluorescence measurements. The photochemical efficiency of PSII in well-hydrated Haberlea leaves was not significantly influenced by temperatures up to 40 °C. F0 reached a maximum at 50 °C, which is connected with blocking of electron transport in reaction center II. The intrinsic efficiency of PSII photochemistry, monitored as Fv/Fm was less vulnerable to heat stress than the quantum yield of PSII electron transport under illumination (ΦPSII). The reduction of ΦPSII values was mainly due to a decrease in the proportion of open PSII centers (qP). Haberlea rhodopensis was very sensitive to photoinhibition. The light intensity of 120 μmol m−2 s−1 sharply decreased the quantum yield of PSII photochemistry and it was almost fully inhibited at 350 μmol m−2 s−1. As could be expected decreased photochemical efficiency of PSII was accompanied by increased proportion of thermal energy dissipation, which is considered as a protective effect regulating the light energy distribution in PSII. When differentiating between the three components of qN it was evident that the energy-dependent quenching, qE, was prevailing over photoinhibitory quenching, qI, and the quenching related to state 1-state 2 transitions, qT, at all light intensities at 25 °C. However, the qE values declined with increasing temperature and light intensities. The qI was higher than qE at 40 °C and it was the major part of qN at 45 °C, indicating a progressing photoinhibition of the photosynthetic apparatus.

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Photosynthetic Performance in Improved ‘KDML105’ Rice (Oryza sativa L.) Lines Containing Drought and Salt Tolerance Genes under Drought and Salt Stress

Pertanika Journal of Tropical Agricultural Science ◽

10.47836/pjtas.43.4.17 ◽

2020 ◽

Vol 43 (4) ◽

Author(s):

Dechudom Pamuta ◽

Meechai Siangliw ◽

Jirawat Sanitchon ◽

Jarunjit Pengrat ◽

Jonaliza L. Siangliw ◽

...

Keyword(s):

Oryza Sativa ◽

Salt Stress ◽

Drought Stress ◽

Salt Tolerance ◽

Quantum Yield ◽

Oryza Sativa L ◽

Photosynthetic Performance ◽

Psii Photochemistry ◽

Drought And Salt Stress ◽

Quantum Yield Of Psii

Rice (Oryza sativa L.) ‘KDML105’ is the most popular aromatic rice originating in Thailand. This cultivar is highly susceptible to abiotic stresses, especially drought and salt stress during the seedling stage. The objective of this study was to investigate the photosynthetic performance in response to drought and salt stress of four improved breeding lines, specifically CSSL94 and CSSL103 (containing drought-tolerant quantitative trait loci: DT-QTLs) and RGD1 and RGD4 (containing a salt-tolerance gene, SKC1), with ‘KDML105’ (susceptible) and DH103 (tolerant to drought and salt stress) as the controls. Rice seedlings were grown for 21 days in hydroponic solutions and then exposed to salt stress (150 mM NaCl) or drought stress (20% PEG6000) for 10 days. The results indicated that when subjected to drought and salt stress, all rice lines/cultivar exhibited significant reductions in net photosynthesis rate (PN), stomatal conductance (gs), transpiration rate (E), the maximal quantum yield of PSII photochemistry (Fv/Fm), the effective quantum yield of PSII photochemistry (Fv’/Fm’), photosynthetic pigments, and SPAD readings, whereas water use efficiency (WUE) and non-photochemical quenching (NPQ) increased. Compared with ‘KDML105’, CSSL94, and CSSL103 were more tolerant to both drought and salinity, showing less reduction in all photosynthetic parameters. For RGD1 and RGD4, it was confirmed that these lines had a higher level of salt tolerance than ‘KDML105’ based on better photosynthetic performance under salt stress, demonstrating that these lines were also more tolerant to drought stress.

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Assessment of Heat-tolerance Potential in QTL Introgressed Lines of Hybrid Rice Restorer, KMR-3R through PS-II Efficiency

International Journal of Environment and Climate Change ◽

10.9734/ijecc/2021/v11i1130540 ◽

2021 ◽

pp. 258-266

Author(s):

V. Jaldhani ◽

D. Sanjeeva Rao ◽

P. Beulah ◽

B. Srikanth ◽

P. R. Rao ◽

...

Keyword(s):

High Temperature ◽

Quantum Yield ◽

Temperature Stress ◽

Heat Tolerance ◽

Photosynthetic Apparatus ◽

High Temperature Stress ◽

Maximum Efficiency ◽

Photochemical Quenching ◽

Psii Photochemistry ◽

Heat Tolerant

Aims: To assess heat-induced PSII damage and efficiency in eight promising backcross introgression lines (BC2F6) of KMR-3R/N22 possessing qHTSF1.1 and qHTSF4.1. Study Design: Randomized Complete Block Design (RCBD) with three replications. Place and Duration of Study: ICAR-Indian Institute of Rice Research, Hyderabad India during wet/rainy (Kharif) season 2018. Methodology: Eight ILs (BC2F6) and parents were evaluated for heat tolerance. The high- temperature stress was imposed by enclosing the crop with a poly cover tent (Polyhouse) just before the anthesis stage. The fluorescence parameters viz., maximum efficiency of PSII photochemistry (Fv/Fm), Electron transport rate (ETR), effective PSII quantum yield (ΦPSII), coefficient of photochemical quenching (qP) and coefficient of non-photochemical quenching (qN) were measured under ambient and high-temperature stress. Results: The heat-tolerance potential of ILs was assessed in terms of PSII activity. The results indicated that significant differences were observed between treatments (T), genotypes (G) and the interaction between T × G. The physiological basis of introgressed QTLs controls the spikelet fertility by maintaining the productive and adaptive strategies in heat-tolerant QTL introgressed lines with stable photosynthetic apparatus (PSII) under high-temperature stress. Conclusion: The Fv/Fm ratio denotes the maximum quantum yield of PSII. The heat-tolerant QTL introgressed lines exhibited stable photosynthetic apparatus (PSII) and noted better performance under high-temperature stress. They may be used as donors for fluorescence traits in breeding rice for high-temperature tolerance.

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