Spatial Imaging and Quantification of Hydrogen Peroxide in Arabidopsis Roots: From Sample Preparation to Image Analysis
Reactive oxygen species (ROS) are central regulators of plant development and stress responses, with hydrogen peroxide (H2O2) acting as a key signaling molecule whose spatial distribution determines adaptive versus damaging outcomes. Accurate detection of H2O2 at tissue and cellular resolution is therefore essential for understanding redox-dependent regulation of plant growth. A variety of techniques have been used to monitor H2O2, including bulk spectrophotometric and fluorometric assays, genetically encoded sensors for real-time measurements, and chemical probes for in situ detection. While these approaches differ in sensitivity, specificity, and temporal resolution, many are limited by a lack of spatial information, technical complexity, or dependence on transgenic material. Here, we present a detailed protocol for 3,3′-diaminobenzidine (DAB)-based histochemical detection of H2O2 in seedling roots, covering staining, imaging, and semi-quantitative image analysis using open-source software (FIJI/ImageJ). The method relies on peroxidase-mediated oxidation of DAB, resulting in a stable, light-resistant, and insoluble precipitate that enables visualization of H2O2 accumulation with high spatial resolution. This protocol provides a robust, accessible, and genetically independent approach for spatial analysis of H2O2 in plant tissues. Its simplicity, compatibility with diverse genotypes and treatments, and suitability for semi-quantitative analysis make it a valuable tool for examining the spatial distribution of H2O2, thereby providing spatial insight into redox-related regulatory processes during plant development and stress responses.
Closed Systems to Study Plant–Filamentous Fungi Associations: Emphasis on Microscopic Analyses
In nature, filamentous fungi interact with plants. These fungi are characterized by rapid growth in numerous substrates and under minimal nutrient requirements. Investigating the interaction of these fungi with their plant hosts under controlled conditions is of importance for many researchers aiming to proceed with molecular or microscopical investigations of their favorite plant–fungus interaction system. The speed of growth of these fungi complicates transferring plant–fungal interaction systems in laboratory conditions. The issue is more complicated when monoxenic conditions are desired, to ensure that only two members (a fungus and a plant) are present in the system under study. Here, two simple closed systems for investigating plant–filamentous fungi associations under laboratory, monoxenic conditions are described, along with their limitations. The plant and fungal growth conditions, methods for sampling, staining, sectioning, and subsequent microscopical imaging of colonized plant tissues with affordable, common laboratory tools are described.
An Image Analysis Pipeline to Quantify Emerging Cracks in Materials or Adhesion Defects in Living Tissues
Using Silicon Polymer Impression Technique and Scanning Electron Microscopy to Measure Stomatal Aperture, Morphology, and Density
Root Aliphatic Suberin Analysis Using Non-extraction or Solvent-extraction Methods
Determining Genome Size from Spores of Seedless Vascular Plants
Documentation of Floral Secretory Glands in Pleurothallidinae (Orchidaceae) Using Scanning Electron Microscopy (SEM)
Cell Wall-bound p-Coumaric and Ferulic Acid Analysis
Sample Preparation for X-ray Micro-computed Tomography of Woody Plant Material and Associated Xylem Visualisation Techniques
Extraction of Intracellular and Cell Wall Proteins from Leaves and Roots of Harsh Hakea