Can Ceylon Leadwort (Plumbago zeylanica L.) Acclimate to Lead Toxicity?—Studies of Photosynthetic Apparatus Efficiency

Ceylon leadwort (Plumbago zeylanica) is ornamental plant known for its pharmacological properties arising from the abundant production of various secondary metabolites. It often grows in lead polluted areas. The aim of presented study was to evaluate the survival strategy of P. zeylanica to lead toxicity via photosynthetic apparatus acclimatization. Shoots of P. zeylanica were cultivated on media with different Pb concentrations (0.0, 0.05, and 0.1 g Pb∙l−1). After a four-week culture, the efficiency of the photosynthetic apparatus of plants was evaluated by Chl a fluorescence measurement, photosynthetic pigment, and Lhcb1, PsbA, PsbO, and RuBisCo protein accumulation, antioxidant enzymes activity, and chloroplast ultrastructure observation. Plants from lower Pb concentration revealed no changes in photosynthetic pigments content and light-harvesting complex (LHCII) size, as well as no limitation on the donor side of Photosystem II Reaction Centre (PSII RC). However, the activity and content of antioxidant enzymes indicated a high risk of limitation on the acceptor side of Photosystem I. In turn, plants from 0.1 g Pb∙l−1 showed a significant decrease in pigments content, LHCII size, the amount of active PSII RC, oxygen-evolving complex activity, and significant remodeling of chloroplast ultrastructure indicated limitation of PSII RC donor side. Obtained results indicate that P. zeylanica plants acclimate to lead toxicity by Pb accumulation in roots and, depending on Pb concentration, by adjusting their photosynthetic apparatus via the activation of alternative (cyclic and pseudocyclic) electron transport pathways.

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Phytotoxicity of Silver Nanoparticles on Tobacco Plants: Evaluation of Coating Effects on Photosynthetic Performance and Chloroplast Ultrastructure

Nanomaterials ◽

10.3390/nano11030744 ◽

2021 ◽

Vol 11 (3) ◽

pp. 744

Author(s):

Petra Peharec Štefanić ◽

Karla Košpić ◽

Daniel Mark Lyons ◽

Lara Jurković ◽

Biljana Balen ◽

...

Keyword(s):

Silver Nanoparticles ◽

Cetyltrimethylammonium Bromide ◽

Photosynthetic Apparatus ◽

Chloroplast Ultrastructure ◽

Photosynthetic Performance ◽

Pigment Content ◽

Inhibitory Effects ◽

Tobacco Plants ◽

Agriculture And Food ◽

The Impact

Silver nanoparticles (AgNPs) are the most exploited nanomaterial in agriculture and food production, and their release into the environment raises concern about their impact on plants. Since AgNPs are prone to biotransformation, various surface coatings are used to enhance their stability, which may modulate AgNP-imposed toxic effects. In this study, the impact of AgNPs stabilized with different coatings (citrate, polyvinylpyrrolidone (PVP), and cetyltrimethylammonium bromide (CTAB)) and AgNO3 on photosynthesis of tobacco plants as well as AgNP stability in exposure medium have been investigated. Obtained results revealed that AgNP-citrate induced the least effects on chlorophyll a fluorescence parameters and pigment content, which could be ascribed to their fast agglomeration in the exposure medium and consequently weak uptake. The impact of AgNP-PVP and AgNP-CTAB was more severe, inducing a deterioration of photosynthetic activity along with reduced pigment content and alterations in chloroplast ultrastructure, which could be correlated to their higher stability, elevated Ag accumulation, and surface charge. In conclusion, intrinsic properties of AgNP coatings affect their stability and bioavailability in the biological medium, thereby indirectly contributing changes in the photosynthetic apparatus. Moreover, AgNP treatments exhibited more severe inhibitory effects compared to AgNO3, which indicates that the impact on photosynthesis is dependent on the form of Ag.

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Zinc oxide nanocatalyst mediates cadmium and lead toxicity tolerance mechanism by differential regulation of photosynthetic machinery and antioxidant enzymes level in cotton seedlings

Toxicology Reports ◽

10.1016/j.toxrep.2021.01.016 ◽

2021 ◽

Vol 8 ◽

pp. 295-302

Author(s):

Priyanka N. ◽

Geetha N. ◽

Manish T. ◽

Sahi S.V. ◽

Venkatachalam P.

Keyword(s):

Zinc Oxide ◽

Antioxidant Enzymes ◽

Lead Toxicity ◽

Differential Regulation ◽

Tolerance Mechanism ◽

Photosynthetic Machinery ◽

Cadmium And Lead

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Mechanisms Involved in Photosynthetic Apparatus Protection Against Lead Toxicity

Radionuclides and Heavy Metals in the Environment - Lead in Plants and the Environment ◽

10.1007/978-3-030-21638-2_7 ◽

2019 ◽

pp. 117-128 ◽

Cited By ~ 1

Author(s):

Krzysztof Tokarz ◽

Barbara Piwowarczyk ◽

Wojciech Makowski

Keyword(s):

Photosynthetic Apparatus ◽

Lead Toxicity

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Physiological Effect of Kinetin on the Photosynthetic Apparatus and Antioxidant Enzymes Activities During Production of Anthurium

Horticultural Plant Journal ◽

10.1016/j.hpj.2018.04.001 ◽

2018 ◽

Vol 4 (5) ◽

pp. 182-192 ◽

Cited By ~ 5

Author(s):

Fabiana B. de MOURA ◽

Marcos R. da S. VIEIRA ◽

Adriano do N. SIMÕES ◽

Sérgio L. FERREIRA-SILVA ◽

Carlos A.V. de SOUZA ◽

...

Keyword(s):

Antioxidant Enzymes ◽

Photosynthetic Apparatus ◽

Physiological Effect ◽

Enzymes Activities ◽

Antioxidant Enzymes Activities

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Application of exogenous glycinebetaine alleviates lead toxicity in pakchoi (Brassica chinensis L.) by promoting antioxidant enzymes and suppressing Pb accumulation

Environmental Science and Pollution Research ◽

10.1007/s11356-021-17760-4 ◽

2021 ◽

Author(s):

Yu Ji ◽

Yanfang Ren ◽

Chuan Han ◽

Wenjia Zhu ◽

jinyu Gu ◽

...

Keyword(s):

Antioxidant Enzymes ◽

Lead Toxicity ◽

Brassica Chinensis ◽

Pb Accumulation

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Freezing Tolerance of Lolium multiflorum/Festuca arundinacea Introgression Forms is Associated with the High Activity of Antioxidant System and Adjustment of Photosynthetic Activity under Cold Acclimation

International Journal of Molecular Sciences ◽

10.3390/ijms21165899 ◽

2020 ◽

Vol 21 (16) ◽

pp. 5899 ◽

Cited By ~ 1

Author(s):

Adam Augustyniak ◽

Izabela Pawłowicz ◽

Katarzyna Lechowicz ◽

Karolina Izbiańska-Jankowska ◽

Magdalena Arasimowicz-Jelonek ◽

...

Keyword(s):

Gene Expression ◽

Reactive Oxygen Species ◽

Cold Acclimation ◽

Antioxidant System ◽

Freezing Tolerance ◽

Photosynthetic Apparatus ◽

Reactive Oxygen Species Generation ◽

Reactive Oxygen ◽

Protein Accumulation ◽

Oxygen Species

Though winter-hardiness is a complex trait, freezing tolerance was proved to be its main component. Species from temperate regions acquire tolerance to freezing in a process of cold acclimation, which is associated with the exposure of plants to low but non-freezing temperatures. However, mechanisms of cold acclimation in Lolium-Festuca grasses, important for forage production in Europe, have not been fully recognized. Thus, two L. multiflorum/F. arundinacea introgression forms with distinct freezing tolerance were used herein as models in the comprehensive research to dissect these mechanisms in that group of plants. The work was focused on: (i) analysis of cellular membranes’ integrity; (ii) analysis of plant photosynthetic capacity (chlorophyll fluorescence; gas exchange; gene expression, protein accumulation, and activity of selected enzymes of the Calvin cycle); (iii) analysis of plant antioxidant capacity (reactive oxygen species generation; gene expression, protein accumulation, and activity of selected enzymes); and (iv) analysis of Cor14b accumulation, under cold acclimation. The more freezing tolerant introgression form revealed a higher integrity of membranes, an ability to cold acclimate its photosynthetic apparatus and higher water use efficiency after three weeks of cold acclimation, as well as a higher capacity of the antioxidant system and a lower content of reactive oxygen species in low temperature.

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Changes in photosynthetic apparatus of mustard (Sinapis alba) cotyledons following cycloheximide and kinetin treatments

Biologia ◽

10.2478/s11756-008-0128-6 ◽

2008 ◽

Vol 63 (5) ◽

Author(s):

Adriana Machlicová ◽

L’udmila Slováková ◽

Ján Hudák

Keyword(s):

Photosynthetic Pigments ◽

Structural Characteristics ◽

Photosynthetic Apparatus ◽

Chloroplast Ultrastructure ◽

Membrane System ◽

Sinapis Alba ◽

Negative Effects ◽

Chlorophyll Pigments ◽

Leaf Mesophyll ◽

Rubisco Subunits

AbstractBiochemical and accompanying structural characteristics of the photosynthetic process were studied in mustard seedlings cultivated on medium with increasing concentrations of cycloheximide alone as well as in combination with various kinetin concentrations. After 7 days of cultivation the contents of total chlorophyll, carotenoids and content of Rubisco in mustard cotyledons were determined. The content of chlorophyll pigments and carotenoids decreased in dependence of cycloheximide concentration. Following antibiotic treatment the content of both Rubisco subunits markedly decreased. In addition cycloheximide caused disturbance in mesophyll organization and chloroplast ultrastructure.Kinetin applied with cycloheximide increased the amount of photosynthetic pigments as well as of Rubisco, compared to the cycloheximide alone. In the seedlings treated with cycloheximide+kinetin the structure of leaf mesophyll and chloroplast membrane system was similar to control. Our results indicate that kinetin diminished the negative effects of cycloheximide on photosynthetic pigments and Rubisco as well as on the structural traits of the cotyledons.

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