Violeta Velikova

Professor Violeta Velikova, DrSc

Bldg. 21, Office 109
Phone: +359-2-9792683

ORCID ID: 0000-0002-3058-919X
ResearcherID: AAE-3251-2021
Research Gate: Violeta Velikova

DSc. Violeta Velikova holds a professor position at the Institute of Plant Physiology and Genetics – Bulgarian Academy of Sciences.

She has published 119 scientific research papers, with total impact factor of 295.045, total citations of 7003 (Scopus), 6358 (Web of Science Core collection) up to March 2023, and H-index of 30/30 (Scopus/Web of Science).

Dr. Velikova has 31-year experience in studying photosynthesis and 23-year experience in investigating biogenic volatile organic compounds. Dr. Velikova studies the interaction between biosphere and atmosphere with emphasis on primary and secondary metabolism of plants under environmental constrains; the impact of changing climatic factors and anthropogenic pollution on photosynthetic productivity. Phenotypic differences between plant populations from contrasting environments for identification of putative stress-responsive metabolites and understanding mechanisms of plant adaptation to stress conditions are also studied. Innovative LED light technology is used to develop more sustainable plant genotypes with increased levels of natural secondary metabolites, which are an important raw material for the food and pharmaceutical industries. Research in the Velikova lab is also focused on the application of innovative agrotechnical substances (biostimulants based on plant protein hydrolysates) and nanomaterials (carbon nanotubes, biocompatible polymer nanoparticles and magnetite), their physiological effects and the possibilities for overcoming adverse abiotic factors.


2020 DSc, Institute of Plant Physiology and Genetics (IPPG), Bulgarian Academy of Sciences, Bulgaria (BAS)
1998 PhD in Plant Physiology, Institute of Plant Physiology (IPP), Bulgarian Academy of Sciences, Bulgaria
1986 MSc in Ecophysiology, Department of Ecology, Biological Faculty, Sofia University “St. Kl. Ohridski”, Bulgaria


2022 – present Chairman of the Scientific Council, IPPG, BAS
2022 – present Leader of the Laboratory of Photosynthesis – activity and regulation, IPPG, BAS
2018 – 2022 Chairman of the Scientific Council, IPPG, BAS
2016 – 2022 Leader of the Laboratory of Photosynthesis – activity and regulation, IPPG, BAS
2014 – 2018 Chairman of the Scientific Council, IPPG, BAS
2014 – 2016 Leader of the Department of Photosynthesis, IPPG, BAS
2012 – present Professor, BAS – IPPG, Sofia, Bulgaria
2006 – 2012 Senior Researcher, BAS – IPP, Sofia, Bulgaria
1999 – 2006 Assistant Professor, BAS – IPP
1988 – 1998 Research Assistant, BAS – IPP


05/2012 – 2014 Alexander von Humboldt fellowship (ID: 1140077), Institute of Biochemical Plant Pathology (BIOP), Helmholtz Zentrum München, Neuherberg, Germany (18 months)
01/2011 – 12/2011 EC – Marie Curie Industry-Academia Partnership and Pathways (IAPP) “Application of innovative PTR-TOF mass spectrometry in plant biology, environmental science and food/food packaging” (PTR-TOF) (project no. 218065), CNR – Institute of Agroenvironmental and Forest Biology, Monterotondo (Rome) and Institute of Plant Protection, Florence, Italy (12 months) (FP 7)
05/2009 – 05/2010 PostDoc position at CNR, Istituto di Biologia Agroambientale e Forestale (IBAF), Rome, Italy (12 months)
01/2009 ACCENT “Access to infrastructures”, Istituto di Biologia Agroambientale e Forestale, Monterotondo Scalo (Rome), Italy (1 month)
07/2008 – 10/2008 European Science Foundation (ESF) – VOCBAS exchange grant – CNR, Istituto di Biologia Agroambientale e Forestale, Italy (4 months)
10/2007 – 12/2007 EC – Marie Curie Research and Training Network “Ecological and physiological functions of biogenic isoprenoids and their impact on the environment” (ISONET) (MRTN-CT-2003-504720) (3 months) (FP 6)
09/2006 – 12/2006 European Science Foundation (ESF) – VOCBAS exchange grant – Lancaster University, Department of Environmental Science, Lancaster, United Kingdom (4 months)
04/2006 – 06/2006 ACCENT “Access to infrastructures”, Istituto di Biologia Agroambientale e Forestale, Monterotondo Scalo (Rome), Italy (3 months)
01/2004 – 12/2004 NATO Science Fellowship Programme – New University of Lisbon, Faculty of Science and Technology, Lisbon, Portugal (12 months)
06/2003 – 11/2003 CNR-NATO Outreach Fellowship – Istituto di Biochimica ed Ecofisiologia Vegetale del CNR, Roma, Italy (6 months)
10/2002 – 12/2002 University of Dundee, Biological Faculty, Scotland (2 months)
07/2002 – 09/2002 CNR-NATO Outreach Fellowship – Istituto di Biochimica ed Ecofisiologia Vegetale del CNR, Roma, Italy (3 months)
05/2001 – 07/2001 NATO fellowship – Aristotle University of Thessaloniki, Faculty of Sciences, School of Biology, Department of Botany, Thessalonoki, Greece (2 months)
10/2000 – 03/2001 CNR-NATO Outreach Fellowship – Istituto di Biochimica ed Ecofisiologia Vegetale del CNR, Roma, Italy (6 months)


(PC = project coordinator)


2018 – 2022 ESA contract №4000122781/18/NL/SC „Design and development of Space Greenhouse Microgravity Specific ENvironment Simulating Equipment (SG µg-SENSE)”
2016 – 2021 COST Action CA15226 “Climate-Smart Forestry in Mountain Regions” (CLIMO) [Memorandum of understanding (MoU): Approval date: 26/02/2016; End of Action:25/02/2021]
2015 – 2017 Bilateral co-operation between BAS and Estonian University if Life Sciences, Tartu (Estonia) “Biogenic volatile organic compounds and their function in plant adaptation to changing environment” (PC)
2012 – 2016 Forest, their Products and Services COST Action FP1204 “Green Infrastructure approach: linking environment with social aspects in studying and managing urban forests” [Memorandum of understanding (MoU), CSO Approval date: 21/11/2012; End of Action:20/11/2016]
2012 – 2016 “Team 2011” PAT – “Manipulation of volatile isoprenoids to improve plant performances against abiotic and biotic stresses” (MAN-VIP) (PC)
2011 – 2015 EU-Environment project “Effects of climate change on air pollution impacts and response strategies for European ecosystems” (ECLAIRE)
2010 – 2012 Bilateral co-operation between BAS and CNR (Italy) “Physiological role of biogenic isoprene against UV-B radiation stress” (PC)
2010 – 2012 Bilateral co-operation between BAS and HAS (Hungary) “Role of supramolecular organization of PSII – LHCII complex in isoprene emitting plants and its relation to thermoprotection”
2009 – 2011 Bilateral co-operation between BAS and TUBITAK (Turkey) “Comparative study of valuable medicinal plants of Achillea millefolium group: physiological and phytochemical approaches, and practical applications”
2007 – 2009 Bilateral co-operation between BAS and CNR (Italy) “Effect of phosphorus availability on the isoprene emission rate” (PC)
2006 – 2008 NATO LST.CLG 982412 “Plants from ultramafic sites as tools for remediation”
2006 – 2008 Bilateral co-operation between BAS and TUBITAK (Turkey) “Drought tolerance in cotton: a biochemical and physiological approach”
2004 – 2007 NATO EAP.RIG.981279 “Ecophysiological effects of isoprene emission” (PC)
2004 – 2006 Bilateral co-operation between BAS and CNR (Italy) “Present and future antioxidant action of plant isoprenoids” (PC)
2004 – 2006 Bilateral co-operation between BAS and HAS (Hungary) “Role of LHCII in the light harvesting and photoprotection”
2002 – 2004 Royal Society grant “Light stress tolerance in plants acclimated to different low-temperature regimes: Role of polyamines”
2002 – 2003 NATO LST.CLG 978838 “Physiological role of endogenous isoprene under different environmental stresses” (PC)
2000 – 2003 Bilateral co-operation between BAS and TUBITAK (Turkey) “Reddening of cotton leaves: causes and biochemical mechanisms”
2000 – 2003 Bilateral co-operation between BAS and HAS (Hungary) “Mechanisms of injury and acclimation of the photosynthetic apparatus and cell metabolism in pea plants under high temperature stress”
1999 – 2000 NATO – LST.CLG 974973 “Low temperature induced photoinhibition in bean plants: recovery and acclimation”
1996 – 1999 Bilateral co-operation between Bulgarian Academy of Sciences (BAS) and Hungarian Academy of Sciences (HAS) “Effect of thermal stress on the macroorganization of antenna system and the regulation of dissipative ways in the chloroplasts of higher plants”


2021 – 2024 National Science Fund, Bulgaria, КP-06-Н49-7 „Natural zeolites as a base for space soil (ZeoSpace)“
2019 – 2022 National Science Fund, Bulgaria, KP-06 PN 36/8 “Exploring the interactions between innovative nanomaterials and higher plants – basis for development of sustainable nanoagronomic practices” (PC)
2019 – 2022 National Research Program:Healthy nutrition for a strong bioeconomy and quality of life”
2014 – 2017 National Science Fund, Bulgaria, B02-8/2012 “Biogenic volatile organic compounds, global climate change, and plant adaptation potential to changing environment” (PC)
2009 – 2012 National Science Fund, Bulgaria, DO 02-137/2009 “Desiccation induced damages and ecological sustainability of plants evaluated in terms of open system thermodynamics model derived from noninvasive biophysical tests”
2007 – 2010 National Science Fund, Bulgaria, ТКB-1604 “Role of isoprene for improving of plant thermotolerance in elevated CO2 environment”
2007 –2010 National Science Fund, Bulgaria, G-5-02 “Biochemical and physiological characteristics of mutant Arabidopsis thaliana plants altered in the H2O2-induced programmed cell death”
1998 – 2001 National Council for Scientific Investigations, Bulgaria, SS-814 “Comparative physiological and biochemical characterization of different genotypes of wheat (Triticum aestivum L.) for determination of their drought tolerance and choice of selection criteria”
1996 – 1999 National Council for Scientific Investigations, Bulgaria, K-603 “Photoinhibition at the background of high and low temperature – common characteristics and differences”
1996 – 1998 National Council for Scientific Investigations, Bulgaria, MU-BAV7 “Influence of simulated acid rain on the functional activity of the photosynthetic apparatus” (PC)
1995 – 1998 National Council for Scientific Investigations, Bulgaria, K-505 “Molecular mechanisms of acclimation of pea plants to low temperatures”
1994 – 1997 National Council for Scientific Investigations, Bulgaria, K-408 “Mechanisms of recovery of the photosynthetic apparatus after temperature and water stress by means of physiologically active substances”
1992 – 1995 National Council for Scientific Investigations, Bulgaria, K-210 “Studies of harmful heavy metal effects on photosynthetic apparatus of pea plants”


Velikova V, Dani KGS, Loreto F. Origin, evolution, and future of isoprene and nitric oxide interactions within leaves. Journal of Experimental Botany 74(3), 688-706, 2023, Darwin Review.

Pollastri S, Velikova V, Castaldini M, Fineschi S, Ghirardo A, Renaut J, Schnitzler J-P, Sergeant K, Winkler B, Zorzan S, Loreto F. 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 12 (2), 333, 2023.

Teneva I, Velikova V, Belkinova D, Moten D, Dzhambazov B. Allelopathic potential of the cyanotoxins Microcystin-LR and Cylindrospermopsin on green algae. Plants 12(6), 1403, 2023.

Weatherall A, Nabuurs G-J, Velikova V, Santopuoli G, Neroj B, Bowditch E, Temperli C, Binder F, Ditmarová L, Jamnická G, Lesinski J, La Porta N, Pach M, Panzacchi P, Sarginci M, Serengil Y, Tognetti R. Chapter 2 – Defning Climate-Smart Forestry. In: Managing Forest Ecosystems, Vol. 40, Tognetti R, Smith M, Panzacchi P (Eds): Climate-Smart Forestry in Mountain Regions. Springer Nature, Switzerland, AG. ISBN 978-3-030-80766-5, ISBN 978-3-030-80767-2. pp. 35-58, 2022. (eBook).

Walter GM, Clark J, Cristaudo A, Terranova D, Nevado B, Catara S, Paunov M, Velikova V, Filatov D, Cozzolino S, Hiscock SJ, Bridle JR. Adaptive divergence generates distinct plastic responses in two closely related Senecio species. Evolution 76(6):1229-1245, 2022.

Popova AV, Vladkova R, Borisova P, Georgieva K, Mihailova G, Velikova V, Tsonev T, Ivanov AG. Photosynthetic response of lutein deficient mutant lut2 of  Arabidopsis thaliana to low temperature at high light. Photosynthetica 60(SI):108-118, 2022.

Vitale E, Velikova V, Tsonev T, Costanzo G, Paradiso R, Arena C. 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 10:e13677, 2022.

Delfine S, Velikova VB, Mastrodonato F. Soil mulching influence spearmint yield, eco-physiological activities and essential oil content in rainfed environment of Southern Italy. Agronomy 12, art. 1521, 2022.

Vitale E, Izzo LG, Amitrano C, Velikova V, Tsonev T, Simoniello P, De Micco V, Arena C. Light quality modulates photosynthesis and antioxidant properties of B. vulgaris L. plants from seeds irradiated with high-energy heavy ions: Implications for cultivation in space. Plants 11 (14), art. 1816, 2022.

Doneva D, Pál M, Brankova L, Szalai G, Tajti J, Khalil R, Ivanovska B, Velikova V, Misheva S, Janda T, Peeva V – The effects of putrescine pre-treatment on osmotic stress responses in drought-tolerant and drought-sensitive wheat seedlings. Physiologia Plantarum 171(2); 200-216, 2021.

Petrova N, Paunov M, Petrov P, Velikova V, Goltsev V, Krumova S – Polymer-modified single-walled carbon nanotubes affect photosystem II photochemistry, intersystem electron transport carriers and photosystem I end acceptors in pea plants. Molecules 26(19):5958, 2021.

Velikova V, Petrova N, Kovács L, Petrova A, Koleva D, Tsonev T, Taneva S, Petrov P, Krumova S – Single-walled carbon nanotubes modify leaf micromorphology, chloroplast ultrastructure and photosynthetic activity of pea plants. International Journal of Molecular Sciences 22(9):4878, 2021.

Vitale E, Velikova V, Tsonev T, Ferrandino I, Capriello T, Arena C – The interplay between light quality and biostimulant application affects the antioxidant capacity and photosynthetic traits of soybean (Glycine max L.). Plants 10(5), 861, 2021.

Vitale E, Vitale L, Costanzo G, Velikova V, Tsonev T, Simoniello P, De Micco V, Arena C – Light spectral composition influences structural and eco‐physiological traits of Solanum lycopersicum L. cv. ‘Microtom’ in response to high‐LET ionizing radiation. Plants 10(8),1752, 2021.

Bowditch E, Santopuoli G, Binder F, del Rio M, La Porta N, Kluvankova T, Lesinski J, Motta R, Pach M, Panzacchi P, Pretzsch H, Temperli C, Tonon G, Smith M, Velikova V, Weatherall A, Tognetti R – What is Climate-Smart Forestry? A definition from a multinational collaborative process focused on mountain regions of Europe. Ecosystem Services 43, art. number 101113, 2020.

Dimitrova S, Paunov M, Pavlova B, Dankov K, Kouzmanova M, Velikova V, Tsonev T, Kalaji HM, Goltsev V – Photosynthetic efficiency of two Platanus orientalis L. ecotypes exposed to moderately high temperature – JIP-test analysis. Photosynthetica 58 (SI): 657-670, 2020.

Velikova V, Arena C, Izzo LG, Tsonev T, Koleva D, Tattini M, Roeva O, De Maio A, Loreto F – Functional and structural leaf plasticity determine photosynthetic performances during drought stress and recovery in two Platanus orientalis populations from contrasting habitats. International Journal of Molecular Sciences 21(11), 3912, 2020.

Brunetti C, Tattini M, Guidi L, Velikova V, Ferrini F, Fini A. An integrated overview of physiological and biochemical responses of Celtis australis to drought stress. Urban Forestry & Urban Greening volume 46, art. num. 126480, 2019.

Hristozkova M, Gigova L, Geneva M, Stancheva I, Velikova V, Marinova G – Influence of mycorrhizal fungi and microalgae dual inoculation on basil plants performance. Gesunde Pflanzen 70(2): 99-107, 2018.

Petrova N, Koleva P, Velikova V, Tsonev T, Andreeva T, Taneva S, Krumova S, Danova K – Relations between photosynthetic performance and polyphenolics productivity of Atemisia alba Turra in in vitro tissue culture. International Journal Bioautomation 22(1), 73-82, 2018.

Velikova V, Tsonev T, Tattini M, Arena C, Krumova S, Koleva D, Peeva V, Stojchev S, Todinova S, Izzo LG, Brunetti C, Stefanova M, Taneva S, Loreto F. Physiological and structural adjustments of two ecotypes of Platanus orientalis L. from different habitats in response to drought and re-watering. Conservation Physiology 6(1):coy073, 2018.

Baldacchini C, Castanheiro A, Maghakyan N, Sgrigna G, Verhelst J, Alonso R, Amorim J, Bellan P, Breuste J, Bühler O, Cântar I, Cariñanos P, Carriero G, Churkina G, Dinca L, Esposito R, Gawronski S, Kern M, Le Thiec D, Moretti M, Ningal T, Rantzoudi E, Sinjur I, Stojanova B, Aničić Urošević M, Velikova V, Zivojinovic I, Sahakyan L, Calfapietra C, Samson R – How does the amount and composition of PM deposit on Platanus acerifolia leaves change across different cities in Europe? Environmental Science & Technology 51 (3), 1147–1156, 2017.

Ahrar M, Doneva D, Tattini M, Brunetti C, Gori A, Rodeghiero M, Wohlfart G, Biasioli F, Varotto C, Loreto F, Velikova V – Phenotipic differences determine drought stress responses in ecotypes of Arundo donax adapted to different environments. Journal of Experimental Botany 68(9): 2439-2451, 2017.

Li M, Xu J, Alarcon AA, Carlin S, Barbaro E, Cappellin L, Velikova V, Vorska U, Loreto F, Varotto C – In planta recapitulation of isoprene synthase evolution from ocimene synthases. Molecular Biology and Evolution 34(10):2583-2599, 2017.

Hristozkova M, Geneva M, Stancheva I, Velikova V – LED spectral composition effects on mycorrhizal symbiosis formation with tomato plants. Applied Soil Ecology 120, 189-196, 2017.

Vanzo E, Merl-Pham J, Velikova V, Ghirardo A, Lindermayr C, Hauck SM, Bernhardt J, Riedel K, Durner J, Schnitzler J-P – Modulation of protein S-nitrosylation by isoprene emission in poplar. Plant Physiology 170 (4), 1945-1961, 2016.

Fu Y, Poli M, Sablok G, Wang B, Liang Y, La Porta N, Velikova V, Loreto F, Li M, Varotto C – Dissection of early transcriptional responses to water stress in Arundo donax L. by unigene-based RNA-Seq. Biotechnology for Biofuels 9, 54, 2016.

Arena C, Tsonev T, Doneva D, De Micco V, Michelozzi M, Brunetti C, Centritto M, Fineschi S, Velikova V, Loreto F – The effect of light quality on growth, photosynthesis, leaf anatomy and secondary metabolites of a monoterpene-emitting herbaceous species (Solanum lycopersicum L.) and an isoprene-emitting tree (Platanus orientalis L.).  Environmental and Experimental Botany 130, 122-132, 2016.

Velikova V, Brunetti C, Tattini M, Doneva D, Ahrar M, Tsonev T, Stefanova M, Ganeva T, Gori A, Ferrini F, Varotto C, Loreto F – Physiological significance of isoprenoids and phenylpropanoids in drought response of Arundinoideae species with contrasting habitats and metabolism. Plant, Cell & Environment 39, 2185-2197, 2016.

Astier J, Loake G, Velikova V, Gaupels F – Editorial: Interplay between NO signalling, ROS and the antioxidant system in plants. Frontiers in Plant Science, section Plant Physiology 7:1731, 2016.

Tattini M, Loreto F, Fini A, Guidi L, Brunetti C, Velikova V, Gori A, Ferrini F – Isoprenoids and phenylpropanoids are part of the antioxidant defense orchestrated daily by drought stressed Platanus x acerifolia plants during Mediterranean summers. New Phytologist 207, 613-626, 2015.

Ahrar M, Doneva D, Koleva D, Romano A, Rodeghiero M, Tsonev T, Biasioli F, Stefanova M, Peeva V, Wohlfahrt G, Loreto F, Varotto C, Velikova V – Isoprene emission in the monocot Arundineae tribe in relation to functional and structural organization of the photosynthetic apparatus. Environmental and Experimental Botany 119: 87-95, 2015.

Velikova V, Müller C, Ghirardo A, Rock TM, Aichler M, Walch A, Schmitt-Kopplin P, Schnitzler JP – Knocking down isoprene emission modifies the lipid matrix of thylakoid membranes and influences the chloroplast ultrastructure in poplar. Plant Physiology 168: 859-870, 2015.

Loreto F, Pollastri S, Fineschi S, Velikova V – Volatile isoprenoids and their importance for protection against environmental constraints in the Mediterranean area. Environmental and Experimental Botany 103, 99-106, 2014 (Review).

Sablok G, Fu Y, Bobbio V, Laura M, Rotino G, Bagnaresi P, Allavena A, Velikova V, Viola R, Loreto F, Li M, Varotto C – Fuelling genetic and metabolic exploration of C3 bioenergy crops through the first reference transcriptome of Arundo donax L. Plant Biotechnology Journal 12(5), 554-567, 2014.

Velikova V, Ghirardo A, Vanzo E, Merl J, Hauck SM, Schnitzler J-P – Genetic manipulation of isoprene emissions in poplar plants remodels the chloroplast proteome. Journal of Proteome Research 13 (4), 2005-2018, 2014.

Tattini M, Velikova V, Vickers C, Brunetti C, Di Ferdinando M, Trivellini A, Fineschi S, Agati G, Ferrini F, Loreto – Isoprene production in transgenic tobacco alters isoprenoids, non-structural carbohydrates and phenylpropanoids metabolism, and protects photosynthesis from drought stress. Plant, Cell and Environment 37 (8), 1950-1964, 2014.

Centritto M, Haworth M, Marino G, Pallozi E, Tsonev T, Velikova V, Nogues I, Loreto F – Isoprene emission aids recovery of photosynthetic performance in transgenic Nicotiana tabacum following high intensity acute UV-B exposure. Plant Science 226, 82-91, 2014.

Brilli F, Tsonev T, Mahmood T, Velikova V, Loreto F, Centritto M – Ultradian variation of isoprene emission, photosynthesis, mesophyll conductance and optimum temperature sensitivity for isoprene emission in water-stressed Eucalyptus citriodora saplings. Journal of Experimental Botany 64(2): 519-528, 2013.

Calfapietra C, Pallozzi E, Lusini I, Velikova V – Modification of BVOC emissions induced by changes in atmospheric CO2 and air pollution levels. In: “Biology, Controls and Models of Tree Volatile Organic Compound Emissions”, eds. Ü. Niinemets & R.K. Monson. Tree Physiology 5, Springer Science+Business Media Dordrecht, CHAPTER 10: pp. 253-284, 2013.

Krumova S, Zhipinova M, Dankov K, Velikova V, Balashev K, Andreeva T, Russinova E, Taneva S – Brassinosteroids regulate the thylakoid membrane architecture and the photosystem II function. Journal of Photochemistry and Photobiology B, 126, 97-104, 2013.

Beckett M, Loreto F, Velikova V, Brunetti C, Di Ferdinando M, Tattini M, Calfapietra C, Farrant JM – Photosynthetic limitations and volatile and non-volatile isoprenoids in the poikilochlorophyllous resurrection plant Xerophyta humilis during dehydration and rehydration. Plant, Cell and Environment 35 (12), 2061-2074, 2012.

Velikova V, La Mantia T, Lauteri M, Michelozzi M, Nogues I, Loreto F – The impact of winter flooding with saline water on foliar carbon uptake and the volatile fraction of leaves and fruits of lemon (Citrus x limon L. (Burm. f.)) trees. Functional Plant Biology 39 (3), 199-213, 2012.

Velikova V, Sharkey TD, Loreto F – Stabilization of thylakoid membranes in isoprene-emitting plants reduces formation of reactive oxygen species. Plant Signaling & Behavior 7(1), 139-141, 2012.

Tsonev T, Velikova V, Yildiz-Aktas L, Gűrel A, Edreva A – Effect of water deficit and potassium fertilization on photosynthetic activity in cotton plants. Plant Biosystems 145 (4), 841-847, 2011.

Velikova V, Tsonev T, Loreto F, Centritto M – Changes in photosynthesis, mesophyll conductance to CO2, and isoprenoid emissions in Populus nigra plants exposed to excess nickel. Environmental Pollution 159, 1058-1066, 2011.

Velikova V, Várkonyi Z, Szabó M, Maslenkova L, Nogues I, Kovács L, Peeva V, Busheva M, Garab G, Sharkey TD, Loreto F – Increased thermostability of thylakoid membranes in isoprene-emitting leaves probed with three biophysical techniques. Plant Physiology 157, 905-916, 2011.

Velikova V, Salerno G, Frati F, Peri E, Conti E, Colazza S, Loreto F – Influence of feeding and oviposition by phytophagous pentatomids on photosynthesis of herbaceous plants. Journal of Chemical Ecology 36: 629-641, 2010.

Vickers CE, Possell M, CI Cojocariu, Velikova VB, Laothawornkitkul J, Ryan A, Mullineaux PM, Hewitt CN – Isoprene synthesis protects transgenic plants from oxidative stress. Plant Cell and Environment 32: 520-531, 2009.

Velikova V, Tsonev T, Barta C, Centritto M, Koleva D, Stefanova M, Busheva M, Loreto F – BVOC emissions, photosynthetic characteristics and changes in chloroplast ultra-structure of Platanus orientalis L. exposed to elevated CO2 and high temperature.  Environmental Pollution 157: 2629-2637, 2009.

Velikova V, Loreto F, Brilli1 F, Stefanov D, Yordanov I – Characterization of juvenile and adult leaves of Eucalyptus globulus showing distinct heteroblastic development: photosynthesis and volatile isoprenoids. Plant Biology 10: 55-64, 2008.

Fares S, Brilli F, Noguès I, Velikova V, Tsonev T, Dagli S, Loreto F – Isoprene emission and primary metabolism in Phragmites australis grown under different phosphorus levels. Plant Biology 10: 38-43, 2008.

Velikova V – Isoprene as a tool for plant protection against abiotic stresses – review. Journal of Plant Interactions 3: 1-15, 2008.

Velikova V, Fares S, Loreto F – Isoprene and nitric oxide reduce damages in leaves exposed to oxidative stress. Plant Cell and Environment 31: 1882-1894, 2008.

Edreva A, Velikova V, Tsonev T, Dagnon S, Gürel A, Aktaş, Gesheva E – Stress-protective role of secondary metabolites: diversity of functions and mechanisms. General and Applied Plant Physiology v. XXXIV (1-2): 67-78, 2008.

Edreva AM, Velikova VB, Tsonev TsD – Phenylamides in plants (review). Russ Journal of Plant Physiology, 54 (3), 325-341, 2007.

Velikova V, Edreva A, Tsonev T, Jones HG – Singlet oxygen quenching by phenylamides and their parent compounds. Zeitschrift fur Naturforschung 62c: 833-838, 2007.

Velikova V, Loreto F, Tsonev T, Brilli F, Edreva A – Isoprene prevents the negative consequences of high temperature stress in Platanus orientalis leaves. Functional Plant Biology, 33: 931-940, 2006.

Stoyanova-Koleva D, Edreva A, Velikova V, Gürel A – Effect of reddening of cotton (Gossypium hirsutum L.) leaves on the ultrastructure of mesophyll cells. Photosynthetica 43(2): 313-316, 2005.

Velikova V, Loreto F – On the relationship between isoprene emission and thermotolerance in Phragmites australis leaves exposed to high temperatures and during the recovery from a heat stress. Plant Cell and Environment 28, 318-327, 2005.

Velikova V, Pinelli P, Loreto F – Consequences of inhibition of isoprene synthesis in Phragmites australis leaves exposed to elevated temperatures. Agriculture, Ecosystems & Environment 106 (2-3): 209-217, 2005.

Velikova V, Pinelli P, Pasqualini S, Reale L, Ferranti F, Loreto F – Isoprene decreases the concentration of nitric oxide in leaves exposed to elevated ozone. New Phytologist 166: 419-426, 2005.

Velikova V, Tsonev T, Pinelli P, Alessio GA, Loreto F – Localized O3-fumigation for field-studies of the impact of different ozone levels on photosynthesis, respiration, electron transport rate and isoprene emission in Mediterranean oak species. Tree Physiology, 25: 1523-1532, 2005.

Velikova V, Edreva A, Loreto F – Endogenous isoprene protects Phragmites australis leaves against singlet oxygen. Physiologia Plantarum 122, 219-225, 2004.

Tsonev T, Velikova V, Georgieva K, Hyde PF, Jones HG – Low temperature enhances photosynthetic down-regulation in French bean (Phaseolus vulgaris L.) plants. Annals of Botany 91: 343-352, 2003.

Velikova V, Tsonev T, Edreva A, Gürel A, Hakerlerler H – Effects of reddening of cotton (Gossypium hirsutum L.) leaves on functional activity of photosynthetic apparatus. Photosynthetica 40 (3): 449-452, 2002.

Loreto F, Velikova V, Di Marco G – Respiration in the light measured by 12CO2 emission in 13CO2 atmosphere in maize leaves. Australian Journal of Plant Physiology 28 (11): 1103-1108, 2001.

Loreto F, Velikova V – Isoprene produced by leaves protects the photosynthetic apparatus against ozone damage, quenches ozone products, and reduces lipid peroxidation of cellular membranes. Plant Physiology 127: 1781-1787, 2001.

Velikova V, Yordanov I, Edreva A – Oxidative stress and some antioxidant systems in acid rain-treated bean plants. Protective role of exogenous polyamines. Plant Science 151: 59-66, 2000.

Yordanov I, Velikova V, Tsonev T – Plant responses to drought, acclimation, and stress tolerance (review). Photosynthetica 38 (1): 171-186, 2000.

Dr. Velikova’s activities prove:

  • For the first time to demonstrate that endogenous isoprene has an important protective role in plants, namely isoprene quenches the amount of hydrogen peroxide formed in leaves expose to ozone and reduces lipid peroxidation of cellular membranes (Loreto and Velikova – Plant Physiology 127:1781-1787, 2001).
  • The protective role of endogenous isoprene against singlet oxygen was also demonstrated (Velikova et al. – Physiologia Plantarum 122:219-225, 2004), suggesting that the protection mechanisms may involve a direct reaction of isoprene with this harmful reactive oxygen species (ROS).
  • Expansion of the work on isoprene antioxidant ability it was demonstrated that isoprene can regulate nitric oxide (NO) and ROS accumulation and this is an effective mechanism to control dangerous compounds formed under oxidative stress conditions, thus attenuating the induction of hypersensitive response leading to programmed cell death (Velikova et al. – New Phytologist 166:419-426, 2005; Velikova et al. – Plant Cell and Environment 31:1882-1894, 2008). Moreover, it is demonstrated that the nitrosative pressure is lower when isoprene is present in the leaf cells. The main target sites of NO action in non-isoprene emitting poplar are proteins related to the light and dark reactions of photosynthesis, the tricarboxylic acid cycle, protein metabolism, and redox regulation. The antioxidative defense system is rearranged in non-isoprene emitting poplar genotype at the protein level and at the level of protein S-nitrosylation strongly supporting the hypothesis that isoprene can alter signaling pathways by modulating to what extent and how rapidly RO and NO signaling molecules are generated within a cell (Vanzo et al. – Plant Physiology 170: 1945-1961, 2016).
  • Evidences are provided that endogenous isoprene is not only able to protect leaves against heat but also helps leaves to recover when the heat stress is alleviated (Velikova and Loreto – Plant Cell Environment 28:318-327, 2005). This protective action was due to ROS-scavenging and membrane-stabilizing properties of isoprene, and it was suggested that endogenous isoprene can contribute to the non-enzymatic defence of the plant (Velikova et al. – Functional Plant Biology 33:931-940, 2006).
  • It was directly demonstrated by using different biophysical techniques that isoprene has crucial role in preserving the intactness of thylakoid membranes under heat stress, and more specifically the functionality of photosystem II, suggesting some modifications in lipid environment due to isoprene presence (Velikova et al. – Plant Physiology 157: 905-916, 2011).
  • It was shown that not only isoprene, but other, higher molecular weight isoprenoids, as cis-beta-ocimene and linalool, may play an important role in plant resistance mechanisms against heavy metal stress (Velikova et al. – Environmental Pollution 159:1058-1066, 2011).
  • The effect of a future climate scenario – elevated CO2 and temperature, on plant stress resistance as mediated by volatile secondary metabolites was also reveal (Velikova et al. – Environment Pollution 157:2629-2637, 2009).
  • It was demonstrated that genetically modified tobacco plants able to emit isoprene were better protected from oxidative stress than naturally non-isoprene emitting tobacco (Vickers et al. – Plant Cell and Environment 32:520-531, 2009).
  • New approach for quantitative and qualitative proteomics based on stable isotope-coded protein labeling (ICPL) in combination with polyacrylamide gel electrophoresis (PAGE) and liquid chromatography tandem mass spectrometry (LC-MS/MS) were used to elucidate the chloroplast proteome of isoprene-emitting and non-isoprene emitting poplars. It was demonstrated that the suppression of isoprene synthase by RNA interference, leading to the development of non-isoprene emitting poplar genotypes, decreased levels of chloroplast proteins involved in photosynthesis and increased levels of histones and ribosomal proteins. The removal of isoprene emission in poplar causes large changes in the proteome of chloroplasts affecting the structural organization of thylakoid membranes. The absence of isoprene synthase activity and consequently of isoprene emission implied a down-regulation of proteins related to light reactions of photosynthesis, redox regulation and oxidative stress defense (Velikova et al. – Journal of Proteome Research 13:2005-2018, 2014).
  • The removal of isoprene emission in poplar causes large changes not only in the chloroplast proteome but also the lipid content affecting the structural organization of thylakoid membranes. It is demonstrated that the total amount of monogalactosyldiacylglycerols, digalactosyldiacylglycerols and phospholipids is reduced in chloroplasts when isoprene emission is blocked. The chloroplasts of non-isoprene emitting poplar are more rounded and contain fewer grana stacks and longer stroma thylakoids, more plastoglobules, and larger associative zones between chloroplasts and mitochondria (Velikova et al. – Plant Physiology 168: 859-870, 2015).

Dr. Velikova’s scientific achievements made significant contribution to the field of plant physiology and biochemistry:

  • The mitochondrial respiration during photosynthesis was measured for the first time in illuminated C4 plant. The results show that a very low amount of respiratory CO2 is released by maize leaves even when they are subject to rapidly developing salt and water stresses. Experimental evidence is also provided that CO2 is released only when photosynthesis is low because of limiting light intensity or in leaves exposed to heat stress. The majority of the CO2 formed through mitochondrial respiration is refixed in the mesophyll when photosynthesis is high. Mitochondrial respiration may become inhibited only under severe water-stress conditions (Loreto et al. – Australian Journal of Plant Physiology 28:1103-1108, 2001).
  • The singlet oxygen quenching properties of phenylamide compounds was demonstrated for the first time. Evidence was obtained that their acidic parent compounds (p-coumaric, caffeic and ferulic), as well as free polyamines (putrescine, spermidine and spermine) can act as quenchers of singlet oxygen, with this ability being dependent on the number of amino groups. The covalent bonding of putrescine with hydroxycinnamic acids results in potentiation of the singlet oxygen quenching ability in the phenylamide conjugates. Thus, both PA and phenylamides implicate in the versatile non-enzymatic ROS-scavenging network of plants, and can play a role in the antioxidant defense, particularly at sites of intensive singlet oxygen generation, such as the photosynthetic centers (Velikova et al. – Zeitschrift für Naturforschung 62c:833-838, 2007). Exogenous polyamines (spermidine and spermine) prevent plants from developing of oxidative stress injuries caused by simulated acid rain. It was suggested that polyamines may “prime” the cell to meet and combat stress by stabilizing membranes and forming a potential of higher “buffering” and antioxidant capacity. The more pronounced protective effect of spermine in comparison with spermidine could be accounted for by its longer chain and greater number of positive charges which allows more important neutralizing and membrane stabilizing ability (Velikova et al. – Plant Science 151:59-66, 2000).
  • It was demonstrated that egg deposition per se may significantly affect the plant’s primary metabolism and reduce photosynthetic activity (Velikova et al. – Journal of Chemical Ecology 36:629-641, 2010).

The awards granted to Dr. Velikova’s proposed projects by various associations, as Alexander von Humboldt Foundation (in 2012), EU-FP7 – Marie Curie Industry-Academia Partnership and Pathways (IAPP) (in 2011), the North Atlantic Treaty Organization (NATO, in 2000, 2001, 2003, 2004), European Science Foundation (ESF, in 2005, 2006, 2008), ACCENT-BIAFLUX (in 2006, 2009) prove her scientific excellence.

[ Top ]

Write to us

Meet us

Acad. G. Bonchev Street, Bldg. 21
1113 Sofia, Bulgaria

Contact us

Phone: +359 2 9792606
Fax: +359 2 8739952