A5001109813- Plant-Microbe Interactions and Immunity
- Plant Molecular Biology Research
- Plant and Biological Electrophysiology Studies
- Plant Stress Responses and Tolerance
- Legume Nitrogen Fixing Symbiosis
- Plant nutrient uptake and metabolism
- Plant Parasitism and Resistance
- Phytoplasmas and Hemiptera pathogens
- Plant Reproductive Biology
- Polysaccharides and Plant Cell Walls
- Mycorrhizal Fungi and Plant Interactions
- Cocoa and Sweet Potato Agronomy
- Plant Pathogens and Fungal Diseases
- Plant Pathogenic Bacteria Studies
- Plant and animal studies
- Insect-Plant Interactions and Control
- Plant Virus Research Studies
- Plant responses to water stress
- Insect symbiosis and bacterial influences
- Plant and Fungal Interactions Research
- Agronomic Practices and Intercropping Systems
- Potato Plant Research
- Mycotoxins in Agriculture and Food
- Photosynthetic Processes and Mechanisms
- Plant tissue culture and regeneration
Friedrich Schiller University Jena
2016-2025
Justus-Liebig-Universität Gießen
2005-2014
Schiller International University
2014
Giessen School of Theology
2009
Senckenberg Research Institute and Natural History Museum Frankfurt/M
2009
Utrecht University
2005
Ludwig-Maximilians-Universität München
1985
Technical University of Munich
1985
Meeting the increasing food and energy demands of a growing population will require development ground-breaking strategies that promote sustainable plant production. Host-induced gene silencing has shown great potential for controlling pest diseases in crop plants. However, while delivery inhibitory noncoding double-stranded (ds)RNA by transgenic expression is promising concept, it requires generation plants which may cause substantial delay application depending on transformability genetic...
According to an established concept, injury of the phloem triggers local sieve plate occlusion including callose-mediated constriction and, possibly, protein plugging pores. Sieve can also be achieved by distant stimuli, depends on passage electropotential waves (EPWs), and is reversible in intact plants. The time-course wound response was studied elements main veins Vicia faba plants using confocal multiphoton microscopy. Only 15–45 s after burning a leaf tip, forisomes (giant bodies...
Ca2+-binding proteins in the watery saliva of Megoura viciae counteract Ca2+-dependent occlusion sieve plates Vicia faba and so prevent shut-down food supply response to stylet penetration. The question arises whether this interaction between aphid sieve-element is a universal phenomenon as inferred by coincidence sieve-tube salivation. For purpose, leaf tips were burnt number plant species from four different families induce remote sieve-plate occlusion. Resultant these was counteracted an...
In stressed plants, electrophysiological reactions (elRs) are presumed to contribute long-distance intercellular communication between distant plant parts. Because of the focus on abiotic stress-induced elRs in recent decades, biotic stress-triggered have been widely ignored. It is likely that challenge identify particular elR types (action potential [AP], variation potential, and system [SP]) was responsible for this course action. Thus, survey focused insect larva feeding (Spodoptera...
This study focuses on the question how and where information acquired by FLS2 perception of flg22 is transformed into electrical signals crucial for generation local systemic defense responses. In Arabidopsis thaliana Vicia faba leaves, density was high in epidermis vascular parenchyma, low mesophyll, absent sieve elements (SEs). Aequorin-based examinations disclosed dual cytosolic Ca 2+ peaks shortly after application, which corresponded with two voltage shifts from to SEs. These were...
Abstract Damage induces remote occlusion of sieve tubes in Vicia faba by forisome dispersion, triggered during the passage an electropotential wave (EPW). This study addresses role Ca2+ channels and cytosolic elevation as a link between EPWs dispersion. channel antagonists affect initial phase EPW well prolonged plateau phase. Resting levels tube ∼50 nM were independently estimated using Ca2+-selective electrodes Ca2+-sensitive dye. Transient changes observed phloem tissue response to...
The relationships between damage-induced electropotential waves (EPWs), sieve tube occlusion, and stop of mass flow were investigated in intact Cucurbita maxima plants. After burning leaf tips, EPWs propagating along the phloem main vein recorded by extra- intracellular microelectrodes. respective EPW profiles (a steep hyperpolarization/depolarization peak followed a prolonged hyperpolarization/depolarization) probably reflect merged action variation potentials. A few minutes after passage...
Piriformospora indica, an endophytic root-colonizing fungus, efficiently promotes plant growth and induces resistance to abiotic stress biotic diseases. P. indica fungal cell wall extract cytoplasmic calcium elevation in host roots. Here, we show that cellotriose (CT) is elicitor-active moiety released by into the medium. CT a mild defense-like response, including production of reactive oxygen species, changes membrane potential, expression genes involved regulation root development....
The endophytic fungus Mortierella hyalina colonizes the roots of Arabidopsis thaliana and stimulates growth biomass production aerial parts but not roots. An exudate fraction from induces rapid transient cytoplasmic Ca2+elevation in Ca2+ response does require well-characterized (co)receptors BAK1, CERK1, FLS2 for pathogen-associated molecular patterns, channels GLR-2.4, GLR-2.5, GLR-3.3 or vacuolar TWO PORE CHANNEL1, which might be involved elevation. We isolated an...
Small (s) RNA molecules are crucial factors in the communication between hosts and their interacting pathogens/pests that can modulate both host defense microbial virulence/pathogenicity known as cross-kingdom interference (ckRNAi). Consistent with this, sRNAs double-stranded (ds) precursors have been adopted to control plant diseases through exogenously applied biopesticides, spray-induced gene silencing (SIGS). While spray proved be effective, mechanisms underlying transfer uptake of...
Plants host numerous endophytic microbes which promote plant performance, in particular under stress. A new fungus was isolated from the leaves of a deciduous wood tree Leucas aspera. Morphological inspection and multilocus phylogeny identified as Trichoderma strain. If applied to Arabidopsis thaliana Nicotiana attenuata , it mainly colonizes their roots strongly promotes initial growth plants on soil. The grows high NaCl or mannitol concentrations, shows predatory capability pathogenic...
Cell wall integrity (CWI) maintenance is central for plant cells. Mechanical and chemical distortions, pH changes, breakdown products of cell polysaccharides activate plasma membrane-localized receptors induce appropriate downstream responses. Microbial interactions alter or destroy the structure wall, connecting CWI to immune Cellulose major polysaccharide in primary secondary wall. Its generates short-chain cellooligomers that Ca2+-dependent We show these responses require malectin...
Abstract In transport phloem, photoassimilates escaping from the sieve tubes are released into apoplasmic space between element (SE)/companion cell (CC) complexes (SE/CCs) and phloem parenchyma cells (PPCs). For uptake respective retrieval, PPCs SE/CCs make use of plasma membrane translocators energized by proton motive force (PMF). Their mutual competitiveness, which essentially determines amount translocated through tubes, therefore depends on PMFs. We measured components PMF, potential...
Vascular tissue was recently shown to be capable of producing nitric oxide (NO), but the production sites and sources were not precisely determined. Here, NO synthesis analysed in phloem Vicia faba response stress- pathogen defence-related compounds. The chemical stimuli added shallow paradermal cortical cuts main veins leaves attached intact plants. bare-lying area visualized by real-time confocal laser scanning microscopy using NO-specific fluorochrome 4,5-diaminofluorescein diacetate...
Fusarium graminearum is one of the most common and potent fungal pathogens wheat (Triticum aestivum), known for causing devastating spike infections grain yield damage. F. a typical soil-borne pathogen that builds up during consecutive cereal cropping. Speculation on systemic colonization cereals by root infection have long existed but not been proven. We assessed rot disease macroscopically in diverse set 12 genotypes microscopically comparative study two with diverging responses. Here, we...
Auxin (indole-3-acetic acid, IAA) is an important phytohormone involved in root growth and development. Root-interacting beneficial pathogenic fungi utilize auxin its target genes to manipulate the performance of their hosts for own needs. In order follow visualize effects fungi-colonized Arabidopsis roots, we used dual reporter construct DR5::EGFP-DR5v2::tdTomato fluorescence microscopy as well LC-MS-based analyses. We demonstrate that endophytic Piriformospora indica Mortierella hyalina...
Verticillium dahliae is a soil-borne vascular pathogen that causes severe wilt symptoms in wide range of plants. Co-culture the fungus with Arabidopsis roots for 24 hours induces many changes gene expression profiles both partners, even before defense-related phytohormone levels are induced plant. Both partners reprogram sugar and amino acid metabolism, activate genes signal perception transduction, induce defense stress responsive genes. Furthermore, analysis suggests redirection from...
Sieve element (SE) protoplasts were liberated by exposing excised phloem strands of Vicia faba to cell wall-degrading enzyme mixtures. Two types SE found: simple with forisome inclusions and composite twin protoplasts—two intermitted a sieve plate—of which one protoplast often includes forisome. Forisomes are giant protein SEs in Fabaceae. Membrane integrity was tested application CFDA, sequestered the form carboxyfluorescein. Further evidence for membrane intactness provided swelling...
In Fabaceae, dispersion of forisomes—highly ordered aggregates sieve element proteins—in response to phytoplasma infection was proposed limit phloem mass flow and, hence, prevent pathogen spread. this study, the involvement filamentous proteins in containment phytoplasmas investigated non-Fabaceae plants. Healthy and infected Arabidopsis plants lacking one or two genes related filament formation—AtSEOR1 (At3g01680), AtSEOR2 (At3g01670), AtPP2-A1 (At4g19840)—were analysed. TEM images revealed...
Cucurbits developed the unique extrafascicular phloem (EFP) as a defensive structure against herbivorous animals. Mechanical leaf injury was previously shown to induce systemic wound response in EFP of pumpkin (Cucurbita maxima). Here, we demonstrate that antioxidant system and protein modifications by NO are strongly regulated during this process. Activities central enzymes dehydroascorbate reductase, glutathione reductase ascorbate were rapidly down-regulated at 30 min with second minimum...
Rhizobia are soil bacteria that induce nodule formation on leguminous plants. In the nodules, they reduce dinitrogen to ammonium can be utilized by Besides nitrogen fixation, rhizobia have other symbiotic functions in plants including phosphorus and iron mobilization protection of against various abiotic stresses salinity. Worldwide, about 20% cultivable 33% irrigation land is saline, it estimated around 50% arable will saline 2050. Salinity inhibits plant growth development, results...