Violeta Velikova - Academia.edu (original) (raw)

Papers by Violeta Velikova

Research paper thumbnail of Allelopathic Potential of the Cyanotoxins Microcystin-LR and Cylindrospermopsin on Green Algae

Plants

Allelopathic interactions are widespread in all aquatic habitats, among all groups of aquatic pri... more Allelopathic interactions are widespread in all aquatic habitats, among all groups of aquatic primary biomass producers, including cyanobacteria. Cyanobacteria are producers of potent toxins called cyanotoxins, whose biological and ecological roles, including their allelopathic influence, are still incompletely understood. The allelopathic potential of the cyanotoxins microcystin-LR (MC-LR) and cylindrospermopsin (CYL) on green algae (Chlamydomonas asymmetrica, Dunaliella salina, and Scenedesmus obtusiusculus) was established. Time-dependent inhibitory effects on the growth and motility of the green algae exposed to cyanotoxins were detected. Changes in their morphology (cell shape, granulation of the cytoplasm, and loss of flagella) were also observed. The cyanotoxins MC-LR and CYL were found to affect photosynthesis to varying degrees in the green algae Chlamydomonas asymmetrica, Dunaliella salina, and Scenedesmus obtusiusculus, affecting chlorophyll fluorescence parameters such a...

Research paper thumbnail of Photosynthetic response of lutein-deficient mutant lut2 of Arabidopsis thaliana to low temperature at high light

Photosynthetica, 2022

AL-actinic light; CEF-cyclic electron flow around PSI; Chl-chlorophyll; F0-minimal fluorescence y... more AL-actinic light; CEF-cyclic electron flow around PSI; Chl-chlorophyll; F0-minimal fluorescence yield of the dark-adapted state; F0'-minimal fluorescence yield of the light-adapted state; Fm-maximal fluorescence yield of the dark-adapted state; Fm'-maximal fluorescence yield of the light-adapted state; Fv-variable chlorophyll fluorescence; Fv/Fm-maximal quantum yield of PSII photochemistry; LCP-light-compensation point; MT-multiple-turnover flash; NPQ-nonphotochemical quenching; P700-reaction center chlorophyll of PSI; P700 +-oxidized form of PSI reaction center; PNmax-saturating level of oxygen evolution; PQ-plastoquinone; qE-energy-dependent component of NPQ; R-recovery; ST-single-turnover flash; WUE-water-use efficiency; Φf,D-quantum yield of nonregulated energy dissipation of PSII; ΦNPQ-quantum yield of the regulated energy dissipation of PSII; ΦPSII-actual photochemical efficiency of PSII. Acknowledgments: This work was financially supported by Bulgarian Science Fund under project KП-06-H26/11. The seeds of the wt and mutant lut2 of Arabidopsis thaliana were a generous gift from Prof. R. Bassi.

Research paper thumbnail of Seed Priming with Single-Walled Carbon Nanotubes Grafted with Pluronic P85 Preserves the Functional and Structural Characteristics of Pea Plants

Nanomaterials, Apr 11, 2023

This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY

Research paper thumbnail of Manipulation of light quality is an effective tool to regulate photosynthetic capacity and fruit antioxidant properties of Solanum lycopersicum L. cv. ‘Microtom’ in a controlled environment

PeerJ

Light quality plays an essential role in setting plant structural and functional traits, includin... more Light quality plays an essential role in setting plant structural and functional traits, including antioxidant compounds. This paper aimed to assess how manipulating the light spectrum during growth may regulate the photosynthetic activity and fruit bioactive compound synthesis in Solanum lycopersicum L. cv. ‘Microtom’ to improve plant physiological performance and fruit nutritional value. Plants were cultivated under three light quality regimes: red-green-blue LEDs (RGB), red-blue LEDs (RB) and white fluorescent lamps (FL), from sowing to fruit ripening. Leaf functional traits, photosynthetic efficiency, Rubisco and D1 protein expression, and antioxidant production in fruits were analyzed. Compared to FL, RGB and RB regimes reduced height and increased leaf number and specific leaf area, enhancing plant dwarf growth. The RGB regime improved photosynthesis and stomatal conductance despite lower biomass, favoring Rubisco synthesis and carboxylation rate than RB and FL regimes. The RB...

Research paper thumbnail of Isoprene-Emitting Tobacco Plants Are Less Affected by Moderate Water Deficit under Future Climate Change Scenario and Show Adjustments of Stress-Related Proteins in Actual Climate

Plants

Isoprene-emitting plants are better protected against thermal and oxidative stresses, which is a ... more Isoprene-emitting plants are better protected against thermal and oxidative stresses, which is a desirable trait in a climate-changing (drier and warmer) world. Here we compared the ecophysiological performances of transgenic isoprene-emitting and wild-type non-emitting tobacco plants during water stress and after re-watering in actual environmental conditions (400 ppm of CO2 and 28 °C of average daily temperature) and in a future climate scenario (600 ppm of CO2 and 32 °C of average daily temperature). Furthermore, we intended to complement the present knowledge on the mechanisms involved in isoprene-induced resistance to water deficit stress by examining the proteome of transgenic isoprene-emitting and wild-type non-emitting tobacco plants during water stress and after re-watering in actual climate. Isoprene emitters maintained higher photosynthesis and electron transport rates under moderate stress in future climate conditions. However, physiological resistance to water stress in...

Research paper thumbnail of Defining Climate-Smart Forestry

Climate-Smart Forestry in Mountain Regions, 2021

Climate-Smart Forestry (CSF) is a developing concept to help policymakers and practitioners devel... more Climate-Smart Forestry (CSF) is a developing concept to help policymakers and practitioners develop focused forestry governance and management to adapt to and mitigate climate change. Within the EU COST Action CA15226, CLIMO (Climate-Smart Forestry in Mountain Regions), a CSF definition was developed considering three main pillars: (1) adaptation to climate change, (2) mitigation of climate change, and (3) the social dimension. Climate mitigation occurs through carbon (C) sequestration by trees, C storage in vegetation and soils, and C substitution by wood. However, present and future climate mitigation depends on the adaptation of trees, woods, and forests to adapt to climate change, which is also driven by societal change.Criteria and Indicators (C & I) can be used to assess the climate smartness of forestry in different conditions, and over time. A suite of C & I that quantify the climate smartness of forestry practices has been developed by experts as guidelines for CSF. This ch...

Research paper thumbnail of Photoinhibition of Photosystem 1

Till recently the term photoinhibition (PI) has been related to PS2 part of photosynthetic electr... more Till recently the term photoinhibition (PI) has been related to PS2 part of photosynthetic electron transport chain, in spite of some publications showing that PS1 can also be inhibited at definite conditions. At chilling temperature and low light intensity PS1 is selectively inhibited while PS2 remains practically unchanged. This review describes the nature of PS1 PI; the differences between PS1 and PS2 PI; PI of PS1 and chilling stress of photo-synthesis; mechanisms of PS1 PI and their targets; reactive oxygen species as the primary cause of photoinhibitory injury of PS1; degradation of PsaB and PsaA gene products-the site of PS1 PI. In the conclusion some questions were put on to be answered in the near future.

Research paper thumbnail of ÉCLAIRE Effects of Climate Change on Air Pollution Impacts and Response Strategies for European Ecosystems Seventh Framework Programme Theme: Environment Project Final Report

The central goal of ECLAIRE is to assess how climate change will alter the extent to which air po... more The central goal of ECLAIRE is to assess how climate change will alter the extent to which air pollutants threaten terrestrial ecosystems. Particular attention has been given to nitrogen compounds, especially nitrogen oxides (NOx) and ammonia (NH3), as well as Biogenic Volatile Organic Compounds (BVOCs) in relation to tropospheric ozone (O3) formation, including their interactions with aerosol components. ECLAIRE has combined a broad program of field and laboratory experimentation and modelling of pollution fluxes and ecosystem impacts, advancing both mechanistic understanding and providing support to European policy makers. The central finding of ECLAIRE is that future climate change is expected to worsen the threat of air pollutants on Europe’s ecosystems. Firstly, climate warming is expected to increase the emissions of many trace gases, such as agricultural NH3, the soil component of NOx emissions and key BVOCs. Experimental data and numerical models show how these effects will tend to increase atmospheric N deposition in future. By contrast, the net effect on tropospheric O3 is less clear. This is because parallel increases in atmospheric CO2 concentrations will offset the temperature-driven increase for some BVOCs, such as isoprene. By contrast, there is currently insufficient evidence to be confident that CO2 will offset anticipated climate increases in monoterpene emissions. Secondly, climate warming is found to be likely to increase the vulnerability of ecosystems towards air pollutant exposure or atmospheric deposition. Such effects may occur as a consequence of combined perturbation, as well as through specific interactions, such as between drought, O3, N and aerosol exposure. These combined effects of climate change are expected to offset part of the benefit of current emissions control policies. Unless decisive mitigation actions are taken, it is anticipated that ongoing climate warming will increase agricultural and other biogenic emissions, posing a challenge for national emissions ceilings and air quality objectives related to nitrogen and ozone pollution. The O3 effects will be further worsened if progress is not made to curb increases in methane (CH4) emissions in the northern hemisphere. Other key findings of ECLAIRE are that: 1) N deposition and O3 have adverse synergistic effects. Exposure to ambient O3 concentrations was shown to reduce the Nitrogen Use Efficiency of plants, both decreasing agricultural production and posing an increased risk of other forms of nitrogen pollution, such as nitrate leaching (NO3-) and the greenhouse gas nitrous oxide (N2O); 2) within-canopy dynamics for volatile aerosol can increase dry deposition and shorten atmospheric lifetimes; 3) ambient aerosol levels reduce the ability of plants to conserve water under drought conditions; 4) low-resolution mapping studies tend to underestimate the extent of local critical loads exceedance; 5) new dose-response functions can be used to improve the assessment of costs, including estimation of the value of damage due to air pollution effects on ecosystems, 6) scenarios can be constructed that combine technical mitigation measures with dietary change options (reducing livestock products in food down to recommended levels for health criteria), with the balance between the two strategies being a matter for future societal discussion. ECLAIRE has supported the revision process for the National Emissions Ceilings Directive and will continue to deliver scientific underpinning into the future for the UNECE Convention on Long-range Transboundary Air Pollution.

Research paper thumbnail of Influence of Mycorrhizal Fungi and Microalgae Dual Inoculation on Basil Plants Performance

Gesunde Pflanzen, 2018

The rhizosphere microbial community is a complex of organisms interconnecting in multifold ways, ... more The rhizosphere microbial community is a complex of organisms interconnecting in multifold ways, acting upon each other and reacting to the surrounding environment. In the present research, we evaluated the influence of dual inoculation with arbuscular mycorrhizal fungi (AMF) and microalgae (Scenedesmus incrassatulus R83 and Synechocystis sp. R10) on basil plants performance. Different modes of basil inoculation (AMF, microalgae and a combination of both) were analyzed. We characterized AMF function (colonization and glomalin-related soil proteins), acid phosphatase activity (in root and soil), plant growth, photosynthetic parameters, secondary metabolites (fluorescence indices of leaf chlorophyll content; flavonols contents; nitrogen balance index), and the activity of plant enzymes linking nitrogen and carbon metabolism (glutamate synthase, aspartate aminotransferase and NADP-malic enzyme). The highest values of biometrical data were as a result of mycorrhiza application alone and in the mixed treatments with both microalgae strains. Dual inoculation with both microalgae and AMF, stimulated mycorrhizal function (concentration of glomalin-related proteins). Indexes of secondary metabolites (flavonols and anthocyanins) increased after treatment with Scenedesmus (Al1 and AM + Al1) compared to control plants. The addition of Synechocystis alone and in combination with fungi positively influenced nitrogen balance index. Different modes of inoculation increased gas-exchange parameters in all variations of inoculations compare to control plants. The results for activities of nitrogen-carbon metabolizing enzymes demonstrated close relationships with the plant growth. The mycorrhizal root colonization of basil may bear considerable economic importance. Thus, the addition of suitable AMF to the rhizosphere would significantly improve the growth and productivity of commercial Ocimum spp. cultivation.

Research paper thumbnail of Soil-Mulching Influence on Spearmint Oil Yield, Ecophysiological Activities and Essential-Oil Content in Rainfed Environment of Southern Italy

Agronomy

The application of soil mulching is widely used to improve crop productivity within semiarid regi... more The application of soil mulching is widely used to improve crop productivity within semiarid regions of Mediterranean environments. A field study was conducted during two consecutive cycles of spearmint (Mentha spicata L.) within the rainfed region of Southern Italy to evaluate the effects of straw mulch cultivation practices on crop yields and ecophysiological activities. Four treatments were evaluated: (1) rainfed with straw mulch (RM), (2) rainfed without straw mulch (R), (3) well-watered control plants (W) and (4) well-watered with straw mulch (WM). The rainfed mulch treatment (RM) significantly improved oil yields and ecophysiological activity of the spearmint in comparison with rainfed (R). The rainfed mulch treatment (RM) showed lower inhibition of photosynthesis and smaller diffusive limitations than control treatment, while in rainfed plants (R) photosynthetic activity and diffusive limitations strongly decreased at the end of crop cycle. The average essential-oil content w...

Research paper thumbnail of MOESM1 of Dissection of early transcriptional responses to water stress in Arundo donax L. by unigene-based RNA-seq

Additional file 1: Table S1. Experimental design, number of reads per library and sampling scheme.

Research paper thumbnail of MOESM2 of Dissection of early transcriptional responses to water stress in Arundo donax L. by unigene-based RNA-seq

Additional file 2: Table S2. Validation of 10 A. donax DEGs by Real Time qrt-PCR.

Research paper thumbnail of Eucalyptus

Ultradian variation of isoprene emission, photosynthesis, mesophyll conductance, and optimum temp... more Ultradian variation of isoprene emission, photosynthesis, mesophyll conductance, and optimum temperature sensitivity for isoprene emission in water-stressed

Research paper thumbnail of Dark drops of prompt chlorophyll fluorescence as a novel approach for evaluation of the photosynthetic machinery state

Analyzing the changes that occur in the photosynthetic machinery of plants is one of the most inf... more Analyzing the changes that occur in the photosynthetic machinery of plants is one of the most informative approaches for evaluation of the plant physiological state, their stress reactions, productivity and the adaptive mechanisms that develop in order to protect the plant in a changing environment. An informative method for detection and analyzing of the photosynthetic process is measuring the chlorophyll a fluorescence emitted from leaves. Illumination of a plant sample induces a rise in the chlorophyll a fluorescence that draws characteristic induction curves which carry broad spectrum of data about every step of the photosynthetic process. Chlorophyll a fluorescence gives two types of signals – prompt (PF) and delayed chlorophyll fluorescence (DF). The Multifunctional Plant Efficiency Analyzer (MPEA), developed by Hansatech is constructed to measure both simultaneously in only one measurement, but as the initial steps of their kinetics overlap they cannot be recorded together wh...

Research paper thumbnail of © 2012 Landes Bioscience. Do not distribute. Stabilization of thylakoid membranes in isoprene-emitting plants reduces formation of reactive oxygen species

*Correspondence to: Francesco Loreto;Email: francesco.loreto@ipp.cnr.itAddendum to: Velikova V, V... more *Correspondence to: Francesco Loreto;Email: francesco.loreto@ipp.cnr.itAddendum to: Velikova V, Varkonyi Z, Szabo M,Maslenkova L, Nogues I, Kovacs V, et al. Increasedthermostability of thylakoid membranes inisoprene-emitting leaves probed with threebiophysical techniques. Plant Physiol 2011;157:905–16; PMID:21807886; http://dx.doi.org/10.1104/pp.111.182519

Research paper thumbnail of Plant-soil Water Status-induced Changes in Physiological and Biochemical Properties of Yarrow

Journal of Essential Oil Bearing Plants, 2016

As medicinal plants are generally collected from the wild flora, it is of fundamental importance ... more As medicinal plants are generally collected from the wild flora, it is of fundamental importance to identify the optimum growth conditions for increasing the yield and quality potential of ex-situ cultivated plants. Effects of different soil water content [20, 40, 60 and 80 % of water holding capacity (WHC)] on growth, physiology and biochemical profile of Achillea millefolium group-related cv. Proa were investigated in the present study. Alterations in drug herbage, chlorophyll content, quantum efficiency of photosystem II, essential oil rate and composition, proline content and lipid peroxidation, antioxidant activity and flavonoid content of the plants under different plant and soil water status were determined. Decrease in soil water status under 40 % of WHC resulted in degradation of chlorophyll pigments, reduction in photochemical efficiency and lower dry matter production. The essential oil (EO) rate of cv. Proa was higher under limited and excessive water content of soil whereas the main component of EO, chamazulene, was negatively correlated with WHC of soil. Our results suggest a general trend of inverse correlation of antioxidant capacity and flavonoid content with essential oil rate in contrast to the positive correlation of these parameters with chamazulene content. The data obtained may serve as a basis of programming the optimum soil moisture conditions for successful cultivation of cv.Proa.

Research paper thumbnail of The Interplay between Light Quality and Biostimulant Application Affects the Antioxidant Capacity and Photosynthetic Traits of Soybean (Glycine max L. Merrill)

Plants, 2021

This paper evaluates the combined effect of biostimulant and light quality on bioactive compound ... more This paper evaluates the combined effect of biostimulant and light quality on bioactive compound production and seedling growth of soybean (Glycine max L. Merrill) plants. Germinated seeds pre-treated with different concentrations (0.01%, 0.05%, 0.5%) of an amino acid-based biostimulant were grown for 4 days at the dark (D), white fluorescent light (FL), full-spectrum LED (FS), and red-blue (RB) light. Potential changes in the antioxidant content of sprouts were evaluated. Part of the sprouts was left to grow at FL, FS, and RB light regimes for 24 days to assess modifications in plants’ anatomical and physiological traits during the early developmental plant stage. The seed pre-treatment with all biostimulant concentrations significantly increased sprout antioxidant compounds, sugar, and protein content compared to the control (seeds treated with H2O). The positive effect on bioactive compounds was improved under FS and RB compared to D and FL light regimes. At the seedling stage, 0...

Research paper thumbnail of Light Spectral Composition Influences Structural and Eco-Physiological Traits of Solanum lycopersicum L. cv. ‘Microtom’ in Response to High-LET Ionizing Radiation

Plants, 2021

This study evaluated if specific light quality (LQ) regimes (white fluorescent, FL; full-spectrum... more This study evaluated if specific light quality (LQ) regimes (white fluorescent, FL; full-spectrum, FS; red-blue, RB) during plant growth modified morphological and photosynthetic traits of Solanum lycopersicum L. ‘Microtom’ plants irradiated at the dry seed stage with 25 Gy 48Ca ions (IR). The irradiation reduced plant size while it increased leaf dry matter content (LDMC) and relative water content (RWC) compared to the control. FS and RB light regimes determined a decrease of plant height and a rise of RWC compared to FL plants. The irradiation under FS and RB regimes favoured the development of dwarf plants and improved the leaf water status. Under the FL regime, irradiated plants showed reduced photosynthesis and stomatal conductance. The opposite behavior was observed in RB irradiated plants in which gas exchanges were significantly stimulated. RB regime enhanced Rubisco expression in irradiated plants also inducing anatomical and functional adjustments (i.e., increase of leaf ...

Research paper thumbnail of Functional and structural consequences of foliar application of single-walled carbon nanotubes on photosynthetic membranes

Various examination methods applied for the detection of pathological changes in the nasal mucosa... more Various examination methods applied for the detection of pathological changes in the nasal mucosa and patency of the nasal passages in patients with the reduced sense of smell ..

Research paper thumbnail of What is Climate-Smart Forestry? A definition from a multinational collaborative process focused on mountain regions of Europe

Research paper thumbnail of Allelopathic Potential of the Cyanotoxins Microcystin-LR and Cylindrospermopsin on Green Algae

Plants

Allelopathic interactions are widespread in all aquatic habitats, among all groups of aquatic pri... more Allelopathic interactions are widespread in all aquatic habitats, among all groups of aquatic primary biomass producers, including cyanobacteria. Cyanobacteria are producers of potent toxins called cyanotoxins, whose biological and ecological roles, including their allelopathic influence, are still incompletely understood. The allelopathic potential of the cyanotoxins microcystin-LR (MC-LR) and cylindrospermopsin (CYL) on green algae (Chlamydomonas asymmetrica, Dunaliella salina, and Scenedesmus obtusiusculus) was established. Time-dependent inhibitory effects on the growth and motility of the green algae exposed to cyanotoxins were detected. Changes in their morphology (cell shape, granulation of the cytoplasm, and loss of flagella) were also observed. The cyanotoxins MC-LR and CYL were found to affect photosynthesis to varying degrees in the green algae Chlamydomonas asymmetrica, Dunaliella salina, and Scenedesmus obtusiusculus, affecting chlorophyll fluorescence parameters such a...

Research paper thumbnail of Photosynthetic response of lutein-deficient mutant lut2 of Arabidopsis thaliana to low temperature at high light

Photosynthetica, 2022

AL-actinic light; CEF-cyclic electron flow around PSI; Chl-chlorophyll; F0-minimal fluorescence y... more AL-actinic light; CEF-cyclic electron flow around PSI; Chl-chlorophyll; F0-minimal fluorescence yield of the dark-adapted state; F0'-minimal fluorescence yield of the light-adapted state; Fm-maximal fluorescence yield of the dark-adapted state; Fm'-maximal fluorescence yield of the light-adapted state; Fv-variable chlorophyll fluorescence; Fv/Fm-maximal quantum yield of PSII photochemistry; LCP-light-compensation point; MT-multiple-turnover flash; NPQ-nonphotochemical quenching; P700-reaction center chlorophyll of PSI; P700 +-oxidized form of PSI reaction center; PNmax-saturating level of oxygen evolution; PQ-plastoquinone; qE-energy-dependent component of NPQ; R-recovery; ST-single-turnover flash; WUE-water-use efficiency; Φf,D-quantum yield of nonregulated energy dissipation of PSII; ΦNPQ-quantum yield of the regulated energy dissipation of PSII; ΦPSII-actual photochemical efficiency of PSII. Acknowledgments: This work was financially supported by Bulgarian Science Fund under project KП-06-H26/11. The seeds of the wt and mutant lut2 of Arabidopsis thaliana were a generous gift from Prof. R. Bassi.

Research paper thumbnail of Seed Priming with Single-Walled Carbon Nanotubes Grafted with Pluronic P85 Preserves the Functional and Structural Characteristics of Pea Plants

Nanomaterials, Apr 11, 2023

This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY

Research paper thumbnail of Manipulation of light quality is an effective tool to regulate photosynthetic capacity and fruit antioxidant properties of Solanum lycopersicum L. cv. ‘Microtom’ in a controlled environment

PeerJ

Light quality plays an essential role in setting plant structural and functional traits, includin... more Light quality plays an essential role in setting plant structural and functional traits, including antioxidant compounds. This paper aimed to assess how manipulating the light spectrum during growth may regulate the photosynthetic activity and fruit bioactive compound synthesis in Solanum lycopersicum L. cv. ‘Microtom’ to improve plant physiological performance and fruit nutritional value. Plants were cultivated under three light quality regimes: red-green-blue LEDs (RGB), red-blue LEDs (RB) and white fluorescent lamps (FL), from sowing to fruit ripening. Leaf functional traits, photosynthetic efficiency, Rubisco and D1 protein expression, and antioxidant production in fruits were analyzed. Compared to FL, RGB and RB regimes reduced height and increased leaf number and specific leaf area, enhancing plant dwarf growth. The RGB regime improved photosynthesis and stomatal conductance despite lower biomass, favoring Rubisco synthesis and carboxylation rate than RB and FL regimes. The RB...

Research paper thumbnail of Isoprene-Emitting Tobacco Plants Are Less Affected by Moderate Water Deficit under Future Climate Change Scenario and Show Adjustments of Stress-Related Proteins in Actual Climate

Plants

Isoprene-emitting plants are better protected against thermal and oxidative stresses, which is a ... more Isoprene-emitting plants are better protected against thermal and oxidative stresses, which is a desirable trait in a climate-changing (drier and warmer) world. Here we compared the ecophysiological performances of transgenic isoprene-emitting and wild-type non-emitting tobacco plants during water stress and after re-watering in actual environmental conditions (400 ppm of CO2 and 28 °C of average daily temperature) and in a future climate scenario (600 ppm of CO2 and 32 °C of average daily temperature). Furthermore, we intended to complement the present knowledge on the mechanisms involved in isoprene-induced resistance to water deficit stress by examining the proteome of transgenic isoprene-emitting and wild-type non-emitting tobacco plants during water stress and after re-watering in actual climate. Isoprene emitters maintained higher photosynthesis and electron transport rates under moderate stress in future climate conditions. However, physiological resistance to water stress in...

Research paper thumbnail of Defining Climate-Smart Forestry

Climate-Smart Forestry in Mountain Regions, 2021

Climate-Smart Forestry (CSF) is a developing concept to help policymakers and practitioners devel... more Climate-Smart Forestry (CSF) is a developing concept to help policymakers and practitioners develop focused forestry governance and management to adapt to and mitigate climate change. Within the EU COST Action CA15226, CLIMO (Climate-Smart Forestry in Mountain Regions), a CSF definition was developed considering three main pillars: (1) adaptation to climate change, (2) mitigation of climate change, and (3) the social dimension. Climate mitigation occurs through carbon (C) sequestration by trees, C storage in vegetation and soils, and C substitution by wood. However, present and future climate mitigation depends on the adaptation of trees, woods, and forests to adapt to climate change, which is also driven by societal change.Criteria and Indicators (C & I) can be used to assess the climate smartness of forestry in different conditions, and over time. A suite of C & I that quantify the climate smartness of forestry practices has been developed by experts as guidelines for CSF. This ch...

Research paper thumbnail of Photoinhibition of Photosystem 1

Till recently the term photoinhibition (PI) has been related to PS2 part of photosynthetic electr... more Till recently the term photoinhibition (PI) has been related to PS2 part of photosynthetic electron transport chain, in spite of some publications showing that PS1 can also be inhibited at definite conditions. At chilling temperature and low light intensity PS1 is selectively inhibited while PS2 remains practically unchanged. This review describes the nature of PS1 PI; the differences between PS1 and PS2 PI; PI of PS1 and chilling stress of photo-synthesis; mechanisms of PS1 PI and their targets; reactive oxygen species as the primary cause of photoinhibitory injury of PS1; degradation of PsaB and PsaA gene products-the site of PS1 PI. In the conclusion some questions were put on to be answered in the near future.

Research paper thumbnail of ÉCLAIRE Effects of Climate Change on Air Pollution Impacts and Response Strategies for European Ecosystems Seventh Framework Programme Theme: Environment Project Final Report

The central goal of ECLAIRE is to assess how climate change will alter the extent to which air po... more The central goal of ECLAIRE is to assess how climate change will alter the extent to which air pollutants threaten terrestrial ecosystems. Particular attention has been given to nitrogen compounds, especially nitrogen oxides (NOx) and ammonia (NH3), as well as Biogenic Volatile Organic Compounds (BVOCs) in relation to tropospheric ozone (O3) formation, including their interactions with aerosol components. ECLAIRE has combined a broad program of field and laboratory experimentation and modelling of pollution fluxes and ecosystem impacts, advancing both mechanistic understanding and providing support to European policy makers. The central finding of ECLAIRE is that future climate change is expected to worsen the threat of air pollutants on Europe’s ecosystems. Firstly, climate warming is expected to increase the emissions of many trace gases, such as agricultural NH3, the soil component of NOx emissions and key BVOCs. Experimental data and numerical models show how these effects will tend to increase atmospheric N deposition in future. By contrast, the net effect on tropospheric O3 is less clear. This is because parallel increases in atmospheric CO2 concentrations will offset the temperature-driven increase for some BVOCs, such as isoprene. By contrast, there is currently insufficient evidence to be confident that CO2 will offset anticipated climate increases in monoterpene emissions. Secondly, climate warming is found to be likely to increase the vulnerability of ecosystems towards air pollutant exposure or atmospheric deposition. Such effects may occur as a consequence of combined perturbation, as well as through specific interactions, such as between drought, O3, N and aerosol exposure. These combined effects of climate change are expected to offset part of the benefit of current emissions control policies. Unless decisive mitigation actions are taken, it is anticipated that ongoing climate warming will increase agricultural and other biogenic emissions, posing a challenge for national emissions ceilings and air quality objectives related to nitrogen and ozone pollution. The O3 effects will be further worsened if progress is not made to curb increases in methane (CH4) emissions in the northern hemisphere. Other key findings of ECLAIRE are that: 1) N deposition and O3 have adverse synergistic effects. Exposure to ambient O3 concentrations was shown to reduce the Nitrogen Use Efficiency of plants, both decreasing agricultural production and posing an increased risk of other forms of nitrogen pollution, such as nitrate leaching (NO3-) and the greenhouse gas nitrous oxide (N2O); 2) within-canopy dynamics for volatile aerosol can increase dry deposition and shorten atmospheric lifetimes; 3) ambient aerosol levels reduce the ability of plants to conserve water under drought conditions; 4) low-resolution mapping studies tend to underestimate the extent of local critical loads exceedance; 5) new dose-response functions can be used to improve the assessment of costs, including estimation of the value of damage due to air pollution effects on ecosystems, 6) scenarios can be constructed that combine technical mitigation measures with dietary change options (reducing livestock products in food down to recommended levels for health criteria), with the balance between the two strategies being a matter for future societal discussion. ECLAIRE has supported the revision process for the National Emissions Ceilings Directive and will continue to deliver scientific underpinning into the future for the UNECE Convention on Long-range Transboundary Air Pollution.

Research paper thumbnail of Influence of Mycorrhizal Fungi and Microalgae Dual Inoculation on Basil Plants Performance

Gesunde Pflanzen, 2018

The rhizosphere microbial community is a complex of organisms interconnecting in multifold ways, ... more The rhizosphere microbial community is a complex of organisms interconnecting in multifold ways, acting upon each other and reacting to the surrounding environment. In the present research, we evaluated the influence of dual inoculation with arbuscular mycorrhizal fungi (AMF) and microalgae (Scenedesmus incrassatulus R83 and Synechocystis sp. R10) on basil plants performance. Different modes of basil inoculation (AMF, microalgae and a combination of both) were analyzed. We characterized AMF function (colonization and glomalin-related soil proteins), acid phosphatase activity (in root and soil), plant growth, photosynthetic parameters, secondary metabolites (fluorescence indices of leaf chlorophyll content; flavonols contents; nitrogen balance index), and the activity of plant enzymes linking nitrogen and carbon metabolism (glutamate synthase, aspartate aminotransferase and NADP-malic enzyme). The highest values of biometrical data were as a result of mycorrhiza application alone and in the mixed treatments with both microalgae strains. Dual inoculation with both microalgae and AMF, stimulated mycorrhizal function (concentration of glomalin-related proteins). Indexes of secondary metabolites (flavonols and anthocyanins) increased after treatment with Scenedesmus (Al1 and AM + Al1) compared to control plants. The addition of Synechocystis alone and in combination with fungi positively influenced nitrogen balance index. Different modes of inoculation increased gas-exchange parameters in all variations of inoculations compare to control plants. The results for activities of nitrogen-carbon metabolizing enzymes demonstrated close relationships with the plant growth. The mycorrhizal root colonization of basil may bear considerable economic importance. Thus, the addition of suitable AMF to the rhizosphere would significantly improve the growth and productivity of commercial Ocimum spp. cultivation.

Research paper thumbnail of Soil-Mulching Influence on Spearmint Oil Yield, Ecophysiological Activities and Essential-Oil Content in Rainfed Environment of Southern Italy

Agronomy

The application of soil mulching is widely used to improve crop productivity within semiarid regi... more The application of soil mulching is widely used to improve crop productivity within semiarid regions of Mediterranean environments. A field study was conducted during two consecutive cycles of spearmint (Mentha spicata L.) within the rainfed region of Southern Italy to evaluate the effects of straw mulch cultivation practices on crop yields and ecophysiological activities. Four treatments were evaluated: (1) rainfed with straw mulch (RM), (2) rainfed without straw mulch (R), (3) well-watered control plants (W) and (4) well-watered with straw mulch (WM). The rainfed mulch treatment (RM) significantly improved oil yields and ecophysiological activity of the spearmint in comparison with rainfed (R). The rainfed mulch treatment (RM) showed lower inhibition of photosynthesis and smaller diffusive limitations than control treatment, while in rainfed plants (R) photosynthetic activity and diffusive limitations strongly decreased at the end of crop cycle. The average essential-oil content w...

Research paper thumbnail of MOESM1 of Dissection of early transcriptional responses to water stress in Arundo donax L. by unigene-based RNA-seq

Additional file 1: Table S1. Experimental design, number of reads per library and sampling scheme.

Research paper thumbnail of MOESM2 of Dissection of early transcriptional responses to water stress in Arundo donax L. by unigene-based RNA-seq

Additional file 2: Table S2. Validation of 10 A. donax DEGs by Real Time qrt-PCR.

Research paper thumbnail of Eucalyptus

Ultradian variation of isoprene emission, photosynthesis, mesophyll conductance, and optimum temp... more Ultradian variation of isoprene emission, photosynthesis, mesophyll conductance, and optimum temperature sensitivity for isoprene emission in water-stressed

Research paper thumbnail of Dark drops of prompt chlorophyll fluorescence as a novel approach for evaluation of the photosynthetic machinery state

Analyzing the changes that occur in the photosynthetic machinery of plants is one of the most inf... more Analyzing the changes that occur in the photosynthetic machinery of plants is one of the most informative approaches for evaluation of the plant physiological state, their stress reactions, productivity and the adaptive mechanisms that develop in order to protect the plant in a changing environment. An informative method for detection and analyzing of the photosynthetic process is measuring the chlorophyll a fluorescence emitted from leaves. Illumination of a plant sample induces a rise in the chlorophyll a fluorescence that draws characteristic induction curves which carry broad spectrum of data about every step of the photosynthetic process. Chlorophyll a fluorescence gives two types of signals – prompt (PF) and delayed chlorophyll fluorescence (DF). The Multifunctional Plant Efficiency Analyzer (MPEA), developed by Hansatech is constructed to measure both simultaneously in only one measurement, but as the initial steps of their kinetics overlap they cannot be recorded together wh...

Research paper thumbnail of © 2012 Landes Bioscience. Do not distribute. Stabilization of thylakoid membranes in isoprene-emitting plants reduces formation of reactive oxygen species

*Correspondence to: Francesco Loreto;Email: francesco.loreto@ipp.cnr.itAddendum to: Velikova V, V... more *Correspondence to: Francesco Loreto;Email: francesco.loreto@ipp.cnr.itAddendum to: Velikova V, Varkonyi Z, Szabo M,Maslenkova L, Nogues I, Kovacs V, et al. Increasedthermostability of thylakoid membranes inisoprene-emitting leaves probed with threebiophysical techniques. Plant Physiol 2011;157:905–16; PMID:21807886; http://dx.doi.org/10.1104/pp.111.182519

Research paper thumbnail of Plant-soil Water Status-induced Changes in Physiological and Biochemical Properties of Yarrow

Journal of Essential Oil Bearing Plants, 2016

As medicinal plants are generally collected from the wild flora, it is of fundamental importance ... more As medicinal plants are generally collected from the wild flora, it is of fundamental importance to identify the optimum growth conditions for increasing the yield and quality potential of ex-situ cultivated plants. Effects of different soil water content [20, 40, 60 and 80 % of water holding capacity (WHC)] on growth, physiology and biochemical profile of Achillea millefolium group-related cv. Proa were investigated in the present study. Alterations in drug herbage, chlorophyll content, quantum efficiency of photosystem II, essential oil rate and composition, proline content and lipid peroxidation, antioxidant activity and flavonoid content of the plants under different plant and soil water status were determined. Decrease in soil water status under 40 % of WHC resulted in degradation of chlorophyll pigments, reduction in photochemical efficiency and lower dry matter production. The essential oil (EO) rate of cv. Proa was higher under limited and excessive water content of soil whereas the main component of EO, chamazulene, was negatively correlated with WHC of soil. Our results suggest a general trend of inverse correlation of antioxidant capacity and flavonoid content with essential oil rate in contrast to the positive correlation of these parameters with chamazulene content. The data obtained may serve as a basis of programming the optimum soil moisture conditions for successful cultivation of cv.Proa.

Research paper thumbnail of The Interplay between Light Quality and Biostimulant Application Affects the Antioxidant Capacity and Photosynthetic Traits of Soybean (Glycine max L. Merrill)

Plants, 2021

This paper evaluates the combined effect of biostimulant and light quality on bioactive compound ... more This paper evaluates the combined effect of biostimulant and light quality on bioactive compound production and seedling growth of soybean (Glycine max L. Merrill) plants. Germinated seeds pre-treated with different concentrations (0.01%, 0.05%, 0.5%) of an amino acid-based biostimulant were grown for 4 days at the dark (D), white fluorescent light (FL), full-spectrum LED (FS), and red-blue (RB) light. Potential changes in the antioxidant content of sprouts were evaluated. Part of the sprouts was left to grow at FL, FS, and RB light regimes for 24 days to assess modifications in plants’ anatomical and physiological traits during the early developmental plant stage. The seed pre-treatment with all biostimulant concentrations significantly increased sprout antioxidant compounds, sugar, and protein content compared to the control (seeds treated with H2O). The positive effect on bioactive compounds was improved under FS and RB compared to D and FL light regimes. At the seedling stage, 0...

Research paper thumbnail of Light Spectral Composition Influences Structural and Eco-Physiological Traits of Solanum lycopersicum L. cv. ‘Microtom’ in Response to High-LET Ionizing Radiation

Plants, 2021

This study evaluated if specific light quality (LQ) regimes (white fluorescent, FL; full-spectrum... more This study evaluated if specific light quality (LQ) regimes (white fluorescent, FL; full-spectrum, FS; red-blue, RB) during plant growth modified morphological and photosynthetic traits of Solanum lycopersicum L. ‘Microtom’ plants irradiated at the dry seed stage with 25 Gy 48Ca ions (IR). The irradiation reduced plant size while it increased leaf dry matter content (LDMC) and relative water content (RWC) compared to the control. FS and RB light regimes determined a decrease of plant height and a rise of RWC compared to FL plants. The irradiation under FS and RB regimes favoured the development of dwarf plants and improved the leaf water status. Under the FL regime, irradiated plants showed reduced photosynthesis and stomatal conductance. The opposite behavior was observed in RB irradiated plants in which gas exchanges were significantly stimulated. RB regime enhanced Rubisco expression in irradiated plants also inducing anatomical and functional adjustments (i.e., increase of leaf ...

Research paper thumbnail of Functional and structural consequences of foliar application of single-walled carbon nanotubes on photosynthetic membranes

Various examination methods applied for the detection of pathological changes in the nasal mucosa... more Various examination methods applied for the detection of pathological changes in the nasal mucosa and patency of the nasal passages in patients with the reduced sense of smell ..

Research paper thumbnail of What is Climate-Smart Forestry? A definition from a multinational collaborative process focused on mountain regions of Europe