TY  - JOUR
AB  - The systemically induced production of volatile organic compounds (VOCs) in undamaged tissues of plants under herbivore attack is still not fully understood, particularly with respect to below- and aboveground signaling. Here, we test the hypotheses that treatment of trees with jasmonic acid (JA) to simulate local herbivory (i) systemically induces VOC emissions in leaves and roots by signal propagation via the vascular bundle system and (ii) that bidirectional signaling occurs between below- and aboveground organs. We applied JA to roots and branches of Fagus sylvatica and Picea abies in a controlled experiment and shielded untreated tissues from volatile cues. VOC emissions and gas exchange were measured continuously over 6-8 days and complemented by quantification of tissue terpenoid storage pools. In contrast to the strong increase in terpenoid emissions from directly treated leaves and needles, which were mainly composed of sesquiterpenes, no systemically induced terpenoid emissions were found. Direct JA treatment of shoots reduced net photosynthesis and stomatal conductance in P. abies by ~50%, while the gas exchange of F. sylvatica remained unaffected. In the root system of P. abies, terpenoid contents increased both locally and systemically in response to belowground JA treatment. Overall, our results challenge the concept of systemically induced terpenoid emissions through vascular JA signaling, which is commonly induced in trees in response to insect herbivory. Instead, our data point toward a possible role of volatile cues in intra-plant signaling.
AU  - Meischner, M.*
AU  - Haberstroh, S.*
AU  - Kreuzwieser, J.*
AU  - Weber, B.
AU  - Ghirardo, A.
AU  - Schnitzler, J.-P.
AU  - Werner, C.*
C1  - 75271
C2  - 57884
CY  - 111 River St, Hoboken 07030-5774, Nj Usa
TI  - Localized response of de novo terpenoid emissions through the jasmonate signaling cascade in two main European tree species.
JO  - Physiol. Plant.
VL  - 177
IS  - 4
PB  - Wiley
PY  - 2025
SN  - 0031-9317
ER  - 

TY  - JOUR
AB  - The barley powdery mildew disease caused by the biotrophic fungus Blumeria hordei (Bh) poses enormous risks to crop production due to yield and quality losses. Plants and fungi can produce and release volatile organic compounds (VOCs) that serve as signals in plant communication and defense response to protect themselves. The present study aims to identify VOCs released by barley (Hordeum vulgare) during Bh-infection and to decipher VOC-induced disease resistance in receiver plants. VOC profiles of susceptible MLO wild type (MLO WT) and a resistant near-isogenic backcross line (mlo5) were characterized over time (one day or three days after Bh inoculation) using TD-GC/MS. Comparative analysis revealed genotype-dependent VOC profiles and significant differences in emission rates for β-caryophyllene, linalool, (Z)-3-hexenol, and methyl salicylate. Furthermore, susceptible barley plants were exposed to the complex VOC bouquet of MLO WT or mlo5 sender plants in plant-to-plant communication. We found that VOC-induced resistance in receiver plants depended on the sender genotype in a Bh susceptibility assay. Additionally, untargeted metabolomics and gene expression studies provide evidence toward an SA-dependent pathway mediating VOC-induced resistance against powdery mildew. The exogenous application of methyl salicylate resulted in the enhanced expression of the BARLEY CHEMICALLY INDUCED-4 marker gene and induced resistance in receiver plants. The findings suggest genotype-dependent alterations in barley VOC profiles during biotrophic plant-fungus interactions and show a VOC-mediated resistance that shares components with salicylic acid-related pathways. The VOC signals identified here could serve as non-invasive markers for disease progression in barley-powdery mildew interactions and as signals for resistance induction in recipient plants.
AU  - Laupheimer, S.*
AU  - Ghirardo, A.
AU  - Kurzweil, L.*
AU  - Weber, B.
AU  - Stark, T.D.*
AU  - Dawid, C.*
AU  - Schnitzler, J.-P.
AU  - Hückelhoven, R.*
C1  - 72695
C2  - 56694
CY  - 111 River St, Hoboken 07030-5774, Nj Usa
TI  - Blumeria hordei affects volatile emission of susceptible and resistant barley plants and modifies the defense response of recipient plants.
JO  - Physiol. Plant.
VL  - 176
IS  - 6
PB  - Wiley
PY  - 2024
SN  - 0031-9317
ER  - 

TY  - JOUR
AB  - Both above- and below-ground parts of plants are constantly challenged with microbes and interact closely with them. Many plant-growth-promoting rhizobacteria, mostly interacting with the plant's root system, enhance the immunity of plants in a process described as induced systemic resistance (ISR). Here, we characterized local induced resistance (IR) triggered by the model PGPR Pseudomonas simiae WCS417r (WCS417) in Arabidopsis thaliana. Hydroponic application of WCS417 to Arabidopsis roots resulted in propagation of WCS417 in/on leaves and the establishment of local IR. WCS417-triggered local IR was dependent on salicylic acid (SA) biosynthesis and signalling and on functional biosynthesis of pipecolic acid and monoterpenes, which are classically associated with systemic acquired resistance (SAR). WCS417-triggered local IR was further associated with a priming of gene expression changes related to SA signalling and SAR. A metabarcoding approach applied to the leaf microbiome revealed a significant local IR-associated enrichment of Flavobacterium sp.. Co-inoculation experiments using WCS417 and At-LSPHERE Flavobacterium sp. Leaf82 suggest that the proliferation of these bacteria is influenced by both microbial and immunity-related, plant-derived factors. Furthermore, application of Flavobacterium Leaf82 to Arabidopsis leaves induced SAR in an NPR1-dependent manner, suggesting that recruitment of this bacterium to the phyllosphere resulted in propagation of IR. Together, the data highlight the importance of plant-microbe-microbe interactions in the phyllosphere and reveal Flavobacterium sp. Leaf82 as a new beneficial promoter of plant health.
AU  - Sommer, A.
AU  - Wenig, M.
AU  - Knappe, C.
AU  - Kublik, S.
AU  - Fösel, B.
AU  - Schloter, M.
AU  - Vlot, A.C.
C1  - 71509
C2  - 56221
CY  - 111 River St, Hoboken 07030-5774, Nj Usa
TI  - A salicylic acid-associated plant-microbe interaction attracts beneficial Flavobacterium sp. to the Arabidopsis thaliana phyllosphere.
JO  - Physiol. Plant.
VL  - 176
IS  - 4
PB  - Wiley
PY  - 2024
SN  - 0031-9317
ER  - 

TY  - JOUR
AB  - Nitric oxide (NO) and various reactive nitrogen species (RNS) produced in cells in normal growth conditions and their enhanced production under stress conditions, are responsible for a variety of biochemical aberrations. Present findings demonstrate that sunflower seedling roots exhibit high sensitivity to salt stress in terms of nitrite accumulation. A significant reduction in S-nitrosoglutathione reductase (GSNOR) activity is evident in response to salt stress. Restoration of GSNOR activity with dithioerythritol (DTT) shows that the enzyme is reversibly inhibited under conditions of 120 mM NaCl. Salt stress mediated S-nitrosylation of cytosolic proteins was analyzed in roots and cotyledons using biotin switch assay. LC-MS/MS analysis revealed opposite patterns of S-nitrosylation in seedling cotyledons and roots. Salt stress enhances S-nitrosylation of proteins in cotyledons whereas roots exhibit denitrosylation of proteins. Highest number of proteins having undergone S-nitrosylation belonged to the category of carbohydrate metabolism followed by other metabolic proteins. Of the total 61 proteins observed to be regulated by S-nitrosylation, 17 are unique to cotyledons, 4 are unique to roots whereas 40 are common to both. Eighteen S-nitrosylated proteins are being reported for the first time in plant systems, including pectinesterase, phospholipase D alpha and calmodulin. Further physiological analysis of glyceraldehyde-3-phosphate dehydrogenase and monodehydro-ascorbate reductase showed that salt stress leads to a reversible inhibition of both these enzymes in cotyledons. However, seedling roots exhibit enhanced enzyme activity under salinity stress. These observations implicate the role of S-nitrosylation and denitrosylation in NO signaling thereby regulating various enzyme activities under salinity stress in sunflower seedlings.
AU  - Jain, P.*
AU  - von Toerne, C.
AU  - Lindermayr, C.
AU  - Bhatla, S.C.*
C1  - 51873
C2  - 43551
CY  - Hoboken
SP  - 49-72
TI  - S-nitrosylation/denitrosylation as a regulatory mechanism of salt stress sensing in sunflower seedlings.
JO  - Physiol. Plant.
VL  - 162
IS  - 1
PB  - Wiley
PY  - 2017
SN  - 0031-9317
ER  - 

TY  - JOUR
AB  - Lolium perenne (cv. AberDart) was grown at 14 locations along a latitudinal gradient across Europe (37-68°N) to study the impact of ultraviolet radiation (UV) and climate on aboveground growth and foliar UV-B absorbing compounds. At each location, plants were grown outdoors for 5 weeks in a replicated UV-B filtration experiment consisting of open, UV-B transparent (cellulose diacetate) and UV-B opaque (polyester) environments. Fourier transform-infrared spectroscopy was used to compare plant metabolite profiles in relation to treatment and location. UV radiation and climatic parameters were determined for each location from online sources and the data were assessed using a combination of anova and multiple regression analyses. Most of the variation in growth between the locations was attributable to the combination of climatic parameters, with minimum temperature identified as an important growth constraint. However, no single environmental parameter could consistently account for the variability in plant growth. Concentrations of foliar UV-B absorbing compounds showed a positive trend with solar UV across the latitudinal gradient; however, this relationship was not consistent in all treatments. The most striking experimental outcome from this study was the effect of presence or absence of filtration frames on UV-absorbing compounds. Overall, the study demonstrates the value of an European approach in studying the impacts of natural UV across a large latitudinal gradient. We have shown the feasibility of coordinated UV filtration at multiple sites but have also highlighted the need for open controls and careful interpretation of plant responses.
AU  - Comont, D.*
AU  - Martinez Abaigar, J.*
AU  - Albert, A.
AU  - Aphalo, P.*
AU  - Causton, D.R.*
AU  - Figueroa, F.L.*
AU  - Gaberscik, A.*
AU  - Llorens, L.*
AU  - Hauser, M.T.*
AU  - Jansen, M.A.*
AU  - Kardefelt, M.*
AU  - de la Coba Luque, P.*
AU  - Neubert, S.*
AU  - Núñez-Olivera, E.*
AU  - Olsen, J.*
AU  - Robson, M.*
AU  - Schreiner, M.*
AU  - Sommaruga, R.*
AU  - Strid, A.*
AU  - Torre, S.*
AU  - Turunen, M.*
AU  - Veljovic-Jovanovic, S.*
AU  - Verdaguer, D.*
AU  - Vidovic, M.*
AU  - Wagner, J.*
AU  - Winkler, J.B.
AU  - Zipoli, G.*
AU  - Gwynn-Jones, D.*
C1  - 8155
C2  - 30001
SP  - 604-618
TI  - UV responses of Lolium perenne raised along a latitudinal gradient across Europe: A filtration study.
JO  - Physiol. Plant.
VL  - 145
IS  - 4
PB  - Wiley-Blackwell
PY  - 2012
SN  - 0031-9317
ER  - 

TY  - JOUR
AB  - Over the past 20 years, nitric oxide (NO) research has generated a lot of interest in various aspects of plant biology. It is now clear that NO plays a role in a wide range of physiological processes in plants. However, in spite of the significant progress that has been made in understanding NO biosynthesis and signaling in planta, several crucial questions remain unanswered. Here we highlight several challenges in NO plant research by summarizing the latest knowledge of NO synthesis and by focusing on the potential NO source(s) and players involved. Our goal is also to provide an overview of how our understanding of NO signaling has been enhanced by the identification of array of genes and proteins regulated by NO.
AU  - Moreau, M.*
AU  - Lindermayr, C.
AU  - Durner, J.
AU  - Klessig, D.F.*
C1  - 1565
C2  - 27186
SP  - 372-383
TI  - NO synthesis and signaling in plant: Where do we stand?
JO  - Physiol. Plant.
VL  - 138
IS  - 4
PB  - Physiologia Plantarum
PY  - 2010
SN  - 0031-9317
ER  - 

TY  - JOUR
AB  - Cytosolic NAD-dependent glyceraldehyde 3-P dehydrogenase (GAPDH; GapC; EC 1.2.1.12) catalyzes the oxidation of triose phosphates during glycolysis in all organisms, but additional functions of the protein has been put forward. Because of its reactive cysteine residue in the active site, it is susceptible to protein modification and oxidation. The addition of GSSG, and much more efficiently of S-nitrosoglutathione, was shown to inactivate the enzymes from Arabidopsis thaliana (isoforms GapC1 and 2), spinach, yeast and rabbit muscle. Inactivation was fully or at least partially reversible upon addition of DTT. The incorporation of glutathione upon formation of a mixed disulfide could be shown using biotinylated glutathione ethyl ester. Furthermore, using the biotin-switch assay, nitrosylated thiol groups could be shown to occur after treatment with nitric oxide donors. Using mass spectrometry and mutant proteins with one cysteine lacking, both cysteines (Cys-155 and Cys-159) were found to occur as glutathionylated and as nitrosylated forms. In preliminary experiments, it was shown that both GapC1 and GapC2 can bind to a partial gene sequence of the NADP-dependent malate dehydrogenase (EC 1.2.1.37; At5g58330). Transiently expressed GapC-green fluorescent protein fusion proteins were localized to the nucleus in A. thaliana protoplasts. As nuclear localization and DNA binding of GAPDH had been shown in numerous systems to occur upon stress, we assume that such mechanism might be part of the signaling pathway to induce increased malate-valve capacity and possibly other protective systems upon overreduction and initial formation of reactive oxygen and nitrogen species as well as to decrease and protect metabolism at the same time by modification of essential cysteine residues.
AU  - Holtgrefe, S.*
AU  - Gohlke, J.*
AU  - Starmann, J.*
AU  - Druce, S.*
AU  - Klocke, S.*
AU  - Altmann, B.*
AU  - Wojtera, J.*
AU  - Lindermayr, C.
AU  - Scheibe, R.*
C1  - 1296
C2  - 26328
SP  - 211-228
TI  - Regulation of plant cytosolic glyceraldehyde 3-phosphate dehydrogenase isoforms by thiol modifications.
JO  - Physiol. Plant.
VL  - 133
IS  - 2
PB  - Wiley-Blackwell
PY  - 2008
SN  - 0031-9317
ER  - 

TY  - JOUR
AB  - Under saline conditions, an optimal cell water balance, possibly mediated by aquaporins, is important to maintain the whole-plant water status. Furthermore, excessive accumulation of boric acid in the soil solution can be observed in saline soils. In this work, the interaction between salinity and excess boron with respect to the root hydraulic conductance (L(0)), abundance of aquaporins (ZmPIP1 and ZmPIP2), ATPase activity and root sap nutrient content, in the highly boron- and salt-tolerant Zea mays L. cv. amylacea, was evaluated. A downregulation of root ZmPIP1 and ZmPIP2 aquaporin contents were observed in NaCl-treated plants in agreement with the L(0) measurements. However, in the H3BO3-treated plants differences in the ZmPIP1 and ZmPIP2 abundance were observed. The ATPase activity was related directly to the amount of ATPase protein and Na+ concentration in the roots, for which an increase in NaCl- and H3BO3+ NaCl-treated plants was observed with respect to untreated and H3BO3-treated plants. Although nutrient imbalance may result from the effect of salinity or H3BO3 alone, an ameliorative effect was observed when both treatments were applied together. In conclusion, our results suggest that under salt stress, the activity of specific membrane components can be influenced directly by boric acid, regulating the functions of certain aquaporin isoforms and ATPase as possible components of the salinity tolerance mechanism.
AU  - Martinez-Ballesta, M. del C.*
AU  - Bastías, E.*
AU  - Zhu, C.
AU  - Schäffner, A.
AU  - González-Moro, B.*
AU  - González-Murua, C.*
AU  - Carvajal, M.*
C1  - 3583
C2  - 25325
SP  - 479-490
TI  - Boric acid and salinity effects on maize roots. Response of aquaporins ZmPIP1 and ZmPIP2, and plasma membrane H+-ATPase, in relation to water and nutrient uptake.
JO  - Physiol. Plant.
VL  - 132
IS  - 4
PB  - Blackwell
PY  - 2008
SN  - 0031-9317
ER  - 

TY  - JOUR
AB  - Young trees of European beech (Fagus sylvatica L.) were exposed in a phytotron to different levels of ozone and CO2 under the climatic simulation of one vegetation period. High ozone levels were simulated similar to high ozone concentration in the field (up to 110 ppb), while CO2 was added as 300 ppm to the present level of ca 380 ppm. Our study describes different aspects of photosynthesis from the leaf level to the reactions of selected thylakoid components at different harvest times during growth of the beech trees under the different fumigation regimes. Ozone effects appeared in the first weeks of the treatment as a stimulation of chlorophyll fluorescence (F-v/F-m), in oxygen production and in ribulose-1,5-bisphosphate carboxylase/oxygenase activity, while the summer and early autumn harvests showed strong reductions in these parameters. Only phosphoenolpyruvate carboxylase (PEPcase) activity remained higher under high ozone. The effects of high CO2 appeared in general as a small stimulation in enzyme activity like PEPcase in spring. However, with increasing time of fumigation, reductions of all parameters were observed. Especially chlorophylls showed strong reductions under high CO2. The combined treatment with high ozone plus high CO2 resulted mostly in an amelioration of the negative ozone effects, although control levels were not reached.
AU  - Lütz, C.*
AU  - Anegg, S.
AU  - Gerant, D.*
AU  - Alaoui-Sossé, B.*
AU  - Gérard, J.*
AU  - Dizengremel, P.*
C1  - 23422
C2  - 31117
SP  - 252-259
TI  - Beech trees exposed to high CO2 and to simulated summer ozone levels: Effects on photosynthesis, chloroplast components and leaf enzyme activity.
JO  - Physiol. Plant.
VL  - 109
IS  - 3
PB  - Wiley
PY  - 2000
SN  - 0031-9317
ER  - 

TY  - JOUR
AU  - Lütz, C.
AU  - Steiger, A.
AU  - Godde, D.
C1  - 19770
C2  - 12917
SP  - 611-617
TI  - The Influence of Air Pollutants and Nutrient Deficiency on the Content and Photosynthesis in Young Spruce Trees.
JO  - Physiol. Plant.
VL  - 86
PY  - 1992
SN  - 0031-9317
ER  -