Salinity Tolerance of Four Hardy Ferns from the Genus Dryopteris Adans. Grown under Different Light Conditions

Hardy ferns form a group of attractive garden perennials with an unknown response to abiotic stresses. The aim of this study was to evaluate the tolerance of three species of ferns of Dryopteris genus (D. affinis, D. atrata and D. filix-mas) and one cultivar (D. filix-mas cv. “Linearis-Polydactylon”) to salinity and light stress. The plants were grown in full sun and shade and watered with 50 and 100 mM dm−3 NaCl solution. All taxa treated with 100 mM NaCl responded with reduced height, leaf greenness index and fresh weight of the above-ground part. In D. affinis and D. atrata salinity caused leaf damage manifested by necrotic spots, which was not observed in the other two taxa. The effect of NaCl depended on light treatments and individual taxon. D. affinis and D. atrata were more tolerant to salinity when growing under shade. Contrary to that, D. filix-mas cv. “Linearis-Polydactylon” seemed to show significantly greater tolerance to this stress under full sun. Salt-treated D. filix-mas cv. “Linearis-Polydactylon” plants accumulated enhanced amounts of K+ in the leaves, which might be associated with the taxon’s tolerance to salinity. Among the investigated genotypes, D. filix-mas cv. “Linearis-Polydactylon” seemed the most and D. affinis and D. atrata the least tolerant to salinity and light stress.

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A chloroplast thylakoid lumen protein is required for proper photosynthetic acclimation of plants under fluctuating light environments

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1712206114 ◽

2017 ◽

Vol 114 (38) ◽

pp. E8110-E8117 ◽

Cited By ~ 15

Author(s):

Jun Liu ◽

Robert L. Last

Keyword(s):

Photosystem Ii ◽

Light Stress ◽

High Irradiance ◽

Light Conditions ◽

Agricultural Plant ◽

Photosynthetic Organisms ◽

Fluctuating Light ◽

Stress Susceptibility ◽

Efficiency And Productivity ◽

Photosynthetic Adaptation

Despite our increasingly sophisticated understanding of mechanisms ensuring efficient photosynthesis under laboratory-controlled light conditions, less is known about the regulation of photosynthesis under fluctuating light. This is important because—in nature—photosynthetic organisms experience rapid and extreme changes in sunlight, potentially causing deleterious effects on photosynthetic efficiency and productivity. Here we report that the chloroplast thylakoid lumenal protein MAINTENANCE OF PHOTOSYSTEM II UNDER HIGH LIGHT 2 (MPH2; encoded byAt4g02530) is required for growth acclimation ofArabidopsis thalianaplants under controlled photoinhibitory light and fluctuating light environments. Evidence is presented thatmph2mutant light stress susceptibility results from a defect in photosystem II (PSII) repair, and our results are consistent with the hypothesis that MPH2 is involved in disassembling monomeric complexes during regeneration of dimeric functional PSII supercomplexes. Moreover,mph2—and previously characterized PSII repair-defective mutants—exhibited reduced growth under fluctuating light conditions, while PSII photoprotection-impaired mutants did not. These findings suggest that repair is not only required for PSII maintenance under static high-irradiance light conditions but is also a regulatory mechanism facilitating photosynthetic adaptation under fluctuating light environments. This work has implications for improvement of agricultural plant productivity through engineering PSII repair.

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Occurrence of neoxanthin and lutein epoxide cycle in parasitic Cuscuta species.

Acta Biochimica Polonica ◽

10.18388/abp.2008_3111 ◽

2008 ◽

Vol 55 (1) ◽

pp. 183-190 ◽

Cited By ~ 7

Author(s):

Jerzy Kruk ◽

Renata Szymańska

Keyword(s):

Substrate Specificity ◽

Xanthophyll Cycle ◽

Higher Plants ◽

Light Stress ◽

High Light ◽

Light Conditions ◽

Strong Light ◽

Zeaxanthin Epoxidase ◽

Typical Response ◽

Cuscuta Species

In the present study, xanthophyll composition of eight parasitic Cuscuta species under different light conditions was investigated. Neoxanthin was not detected in four of the eight species examined, while in others it occurred at the level of several percent of total xanthophylls. In C. gronovii and C. lupuliformis it was additionally found that the neoxanthin content was considerably stimulated by strong light. In dark-adapted plants, lutein epoxide level amounted to 10-22% of total xanthophylls in only three species, the highest being for C. lupuliformis, while in others it was below 3%, indicating that the lutein epoxide cycle is limited to only certain Cuscuta species. The obtained data also indicate that the presence of the lutein epoxide cycle and of neoxanthin is independent and variable among the Cuscuta species. The xanthophyll cycle carotenoids violaxanthin, antheraxanthin and zeaxanthin were identified in all the examined species and occurred at the level found in other higher plants. The xanthophyll and lutein epoxide cycle pigments showed typical response to high light stress. The obtained results also suggest that the ability of higher plants to synthesize lutein epoxide probably does not depend on the substrate specificity of zeaxanthin epoxidase but on the availability of lutein for the enzyme.

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Influence of light intensity and salt-treatment on mode of photosynthesis and enzymes of the antioxidative response system of Mesembryanthemum crystallinum

Functional Plant Biology ◽

10.1071/pp00135 ◽

2002 ◽

Vol 29 (1) ◽

pp. 13 ◽

Cited By ~ 44

Author(s):

Fernando Broetto ◽

Ulrich Lüttge ◽

Rafael Ratajczak

Keyword(s):

Light Stress ◽

High Light ◽

Mesembryanthemum Crystallinum ◽

Stress Factors ◽

Lag Phase ◽

Light Conditions ◽

Cam Plants ◽

Salt Treatment ◽

Sod Activity ◽

Antioxidative Response

The metabolic switch from C3-photosynthesis to crassulacean acid metabolism (CAM),and the antioxidative response of Mesembryanthemum crystallinum L. plants cultured under severe salt stress and high light intensities, and a combination of both stress conditions, were studied. High light conditions led to a more rapid CAM induction than salinity. The induction time was still shortened when both stress factors were combined. A main pattern observed in CAM plants was a decrease in mitochondrial Mn–superoxide dismutase (SOD) activity during the day. The activities of the chloroplastic Fe–SOD and cytosolic CuZn–SOD were increased due to salt treatment after a lag phase, while catalase activity was decreased. Combination of salt and light stress did not lead to a higher SOD activity as found after application of one stress factor alone, indicating that there is a threshold level of the oxidative stress response. The fact that salt-stressed plants grown under high light conditions showed permanent photoinhibition and lost the ability for nocturnal malate storage after 9 d of treatment indicate serious malfunction of metabolism, leading to accelerated senescence. Comparison of CuZn–SOD activity with CuZn–SOD protein amount, which was determined immunologically, indicates that the activity of the enzyme is at least partially post-translationally regulated.

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Isotonic Beverage Pigmented with Water-Dispersible Emulsion from Astaxanthin Oleoresin

Molecules ◽

10.3390/molecules25040841 ◽

2020 ◽

Vol 25 (4) ◽

pp. 841

Author(s):

Pedro Cerezal Mezquita ◽

Carolina Espinosa Álvarez ◽

Jenifer Palma Ramírez ◽

Waldo Bugueño Muñoz ◽

Francisca Salinas Fuentes ◽

...

Keyword(s):

Light Stress ◽

Color Difference ◽

Vital Role ◽

Oxygen Radical ◽

Light Conditions ◽

Rapid Degradation ◽

Water Dispersible ◽

Red Color ◽

Initial Content ◽

Dark Conditions

Astaxanthin is a powerful antioxidant, because it neutralizes free radicals and plays a vital role in the prevention of human diseases. The objective of this work was to develop an isotonic beverage (IB) of orange-red color, using an astaxanthin oleoresin emulsion (AOE) that is dispersible in water. This was carried out in order to simulate the color of commercial isotonic beverages (CIB) prepared from artificial pigments. The size of the AOE micelles ranged from 0.15 to 7.60 µm2. The color difference (ΔE) was similar for the samples exposed to dark as well as light conditions. The samples subjected to light stress showed pigment degradation after seven days, followed by a decrease in the concentration of astaxanthin; whereas, the samples exposed to dark conditions remained stable for seven days and then showed a decrease in the concentration of astaxanthin (this decrease ranged from 65% to 76% when compared to the initial content) after a period of 91 days. For the astaxanthin oleoresin (AO) and AOE, the oxygen radical absorbance capacity (ORAC) values reached 5224 and 1968 µmol of trolox equivalents (TE)/100 g, respectively. When exposed to light conditions, the addition of AOE in the IB led to its rapid degradation, while it remained stable in the samples exposed to the dark conditions.

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Genome-Wide Identification and Expression Analyses of the Fibrillin Family Genes Reveal Their Involvement in the Photoprotection in Cucumber

10.20944/preprints201805.0330.v1 ◽

2018 ◽

Author(s):

Inyoung Kim ◽

Sang-Choon Lee ◽

Eun-Ha Kim ◽

Kiwhan Song ◽

Tae-Jin Yang ◽

...

Keyword(s):

Low Temperature ◽

Dna Sequences ◽

Light Stress ◽

High Light ◽

Light Conditions ◽

Transcript Levels ◽

Photosynthetic Organisms ◽

Conserved Domain ◽

Genome Wide ◽

Cucumber Genome

Fibrillin (FBN) is a plastid lipid-associated protein found in photosynthetic organisms from cyanobacteria to plants. In this study, 10 CsaFBN genes were identified in genomic DNA sequences of cucumber (Chinese long and Gy14) through database searches using the conserved domain of FBN and the 14 FBN genes of Arabidopsis. Phylogenetic analysis of CsaFBN protein sequences showed that there was no counterpart of Arabidopsis and rice FBN5 in the cucumber genome. FBN5 is essential for growth in Arabidopsis and rice; its absence in cucumber may be because of incomplete genome sequences or that another FBN carries out its functions. Among the 10 CsaFBN genes, CsaFBN1 and CsaFBN9 were the most divergent in terms of nucleotide sequences. Most of the CsaFBN genes were expressed in the leaf, stem, and fruit. CsaFBN4 showed the highest mRNA expression levels in various tissues, followed by CsaFBN6, CsaFBN1, and CsaFBN9. High-light stress combined with low temperature decreased photosynthetic efficiency and highly induced transcript levels of CsaFBN1, CsaFBN6, and CsaFBN11, which decreased after 24 h treatment. Transcript levels of the other seven genes were changed only slightly. This result suggests that CsaFBN1, CsaFBN6, and CsaFBN11 may be involved in photoprotection under high-light conditions at low temperature.

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Photosynthetic potential of sun and shade Viola species

Canadian Journal of Botany ◽

10.1139/b84-171 ◽

1984 ◽

Vol 62 (6) ◽

pp. 1273-1278 ◽

Cited By ~ 10

Author(s):

William F. Curtis

Keyword(s):

Dark Respiration ◽

Photosynthetic Performance ◽

Light Conditions ◽

Low Light ◽

Light Regimes ◽

Photosynthetic Plasticity ◽

Photosynthetic Potential ◽

Photosynthetic Responses ◽

Sun And Shade ◽

Meadow Species

The photosynthetic responses of a forest floor violet (Viola blanda) and a related meadow species (Viola flmbriatula) grown under controlled conditions were measured to test the prediction that these two species were photosynthetically shade and sun adapted, respectively. Based on their low photosynthetic and dark respiration rates, and low light saturation and compensation points, both violets can be classified as shade-tolerant. The forest species was photosynthetically and morphologically inflexible when grown under high light conditions, which led to chlorosis and greatly decreased photosynthetic performance. Conversely, the meadow species was both photosynthetically and morphologically flexible; its photosynthetic performance allowed it to grow well under both high and low light regimes. As a consequence, morphological flexibility may play a greater role than physiological (i.e., photosynthetic) plasticity in regulating the distribution of these two violets under field conditions.

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Morphological and Photosynthetic Response to High and Low Irradiance ofAeschynanthus longicaulis

The Scientific World JOURNAL ◽

10.1155/2014/347461 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

Qiansheng Li ◽

Min Deng ◽

Yanshi Xiong ◽

Allen Coombes ◽

Wei Zhao

Keyword(s):

Light Stress ◽

High Irradiance ◽

Anthocyanin Content ◽

Light Conditions ◽

Leaf Color ◽

Low Light ◽

Light Levels ◽

Chlorophyll Fluorescence Parameter ◽

Fluorescence Parameter ◽

Length Width

Aeschynanthus longicaulisplants are understory plants in the forest, adapting to low light conditions in their native habitats. To observe the effects of the high irradiance on growth and physiology, plants were grown under two different light levels, PPFD 650 μmol·m–2·s–1and 150 μmol·m–2·s–1for 6 months. Plants under high irradiance had significantly thicker leaves with smaller leaf area, length, width, and perimeter compared to the plants grown under low irradiance. Under high irradiance, the leaf color turned yellowish and the total chlorophyll decreased from 5.081 mg·dm−2to 3.367 mg·dm−2. The anthocyanin content of high irradiance leaves was double that of those under low irradiance. The plants under high irradiance had significantly lower Amax(5.69 μmol·m–2·s–1) and LSP (367 μmol·m–2·s–1) and higher LCP (21.9 μmol·m–2·s–1). The chlorophyll fluorescence parameterFv/Fmwas significantly lower and NPQ was significantly higher in high irradiance plants. RLCs showed significantly lowerETRmax⁡andEkin plants under high irradiance. It can be concluded that the maximum PPFD of 650 μmol·m–2·s–1led to significant light stress and photoinhibition ofA. longicaulis.

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Degradation of the Light-Stress Protein is Mediated by an ATP-Independent, Serine-Type Protease Under Low-Light Conditions

European Journal of Biochemistry ◽

10.1111/j.1432-1033.1996.00591.x ◽

1996 ◽

Vol 236 (2) ◽

pp. 591-599 ◽

Cited By ~ 24

Author(s):

Iwona Adamska ◽

Marika Lindahl ◽

Margrit Roobol-Boza ◽

Bertil Andersson

Keyword(s):

Light Stress ◽

Stress Protein ◽

Light Conditions ◽

Low Light

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Defoliation Significantly Suppressed Plant Growth Under Low Light Conditions in Two Leguminosae Species

Frontiers in Plant Science ◽

10.3389/fpls.2021.777328 ◽

2022 ◽

Vol 12 ◽

Author(s):

Ning Wang ◽

Tianyu Ji ◽

Xiao Liu ◽

Qiang Li ◽

Kulihong Sairebieli ◽

...

Keyword(s):

Plant Growth ◽

Combined Treatment ◽

Chlorophyll Concentration ◽

Light Stress ◽

Early Period ◽

Light Treatment ◽

High Light ◽

Herbivorous Insects ◽

Light Conditions ◽

Low Light

Seedlings in regenerating layer are frequently attacked by herbivorous insects, while the combined effects of defoliation and shading are not fully understood. In the present study, two Leguminosae species (Robinia pseudoacacia and Amorpha fruticosa) were selected to study their responses to combined light and defoliation treatments. In a greenhouse experiment, light treatments (L+, 88% vs L−, 8% full sunlight) and defoliation treatments (CK, without defoliation vs DE, defoliation 50% of the upper crown) were applied at the same time. The seedlings’ physiological and growth traits were determined at 1, 10, 30, and 70 days after the combined treatment. Our results showed that the effects of defoliation on growth and carbon allocation under high light treatments in both species were mainly concentrated in the early stage (days 1–10). R. pseudoacacia can achieve growth recovery within 10 days after defoliation, while A. fruticosa needs 30 days. Seedlings increased SLA and total chlorophyll concentration to improve light capture efficiency under low light treatments in both species, at the expense of reduced leaf thickness and leaf lignin concentration. The negative effects of defoliation treatment on plant growth and non-structural carbohydrates (NSCs) concentration in low light treatment were significantly higher than that in high light treatment after recovery for 70 days in R. pseudoacacia, suggesting sufficient production of carbohydrate would be crucial for seedling growth after defoliation. Plant growth was more sensitive to defoliation and low light stress than photosynthesis, resulting in NSCs accumulating during the early period of treatment. These results illustrated that although seedlings could adjust their resource allocation strategy and carbon dynamics in response to combined defoliation and light treatments, individuals grown in low light conditions will be more suppressed by defoliation. Our results indicate that we should pay more attention to understory seedlings’ regeneration under the pressure of herbivorous insects.

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