Redox Status-Selective Imaging of Iron in Vegetative and Pathogenic Fungal Cells Using Fluorescent Dyes Synthesized Via Simple Chemical Reactions.

Iron plays a prominent role in various biological processes and is an essential element in almost all organisms, including plant-pathogenic fungi. As a transition element, iron occurs in two redox states, Fe and Fe, the transition between which generates distinct reactive oxygen species (ROS) such as HO, OH anions, and toxic OH· radicals. Thus, the redox status of Fe determines ROS formation in pathogen attack and plant defense and governs the outcome of pathogenic interactions.

The serine-threonine protein kinase Snf1 orchestrates the expression of plant cell wall-degrading enzymes and is required for full virulence of the maize pathogen Colletotrichum graminicola.

Colletotrichum graminicola, the causal agent of maize leaf anthracnose and stalk rot, differentiates a pressurized infection cell called an appressorium in order to invade the epidermal cell, and subsequently forms biotrophic and necrotrophic hyphae to colonize the host tissue. While the role of force in appressorial penetration is established (Bechinger et al., 1999), the involvement of cell wall-degrading enzymes (CWDEs) in this process and in tissue colonization is poorly understood, due to the enormous number and functional redundancy of these enzymes.

Natural Urease Inhibitors Reduce the Severity of Disease Symptoms, Dependent on the Lifestyle of the Pathogens.

The development of new anti-ureolytic compounds is of great interest due to the newly discovered role of urease inhibitors in crop protection. Purine degradation and the generation of ammonium by urease are required for the full virulence of biotrophic and hemibiotrophic fungal plant pathogens. Accordingly, chemicals displaying urease inhibitor activity may be used as a novel class of fungicides.

The Small Ras Superfamily GTPase Rho4 of the Maize Anthracnose Fungus Is Required for β-1,3-glucan Synthesis, Cell Wall Integrity, and Full Virulence.

Small Ras superfamily GTPases are highly conserved regulatory factors of fungal cell wall biosynthesis and morphogenesis. Previous experiments have shown that the Rho4-like protein of the maize anthracnose fungus , formerly erroneously annotated as a Rho1 protein, physically interacts with the β-1,3-glucan synthase Gls1 (Lange et al., 2014; Curr.

Fungal Pathogenesis-Related Cell Wall Biogenesis, with Emphasis on the Maize Anthracnose Fungus .

The genus harbors many plant pathogenic species, several of which cause significant yield losses in the field and post harvest. Typically, in order to infect their host plants, spores germinate, differentiate a pressurized infection cell, and display a hemibiotrophic lifestyle after plant invasion. Several factors required for virulence or pathogenicity have been identified in different species, and adaptation of cell wall biogenesis to distinct stages of pathogenesis has been identified as a major pre-requisite for the establishment of a compatible parasitic fungus-plant interaction.

Correlating the Genetic and Physical Map of Barley Chromosome 3H Revealed Limitations of the FISH-Based Mapping of Nearby Single-Copy Probes Caused by the Dynamic Structure of Metaphase Chromosomes.

Genetic maps are based on the recombination frequency of molecular markers which often show different positions in comparison to the corresponding physical maps. To decipher the position and order of DNA sequences genetically mapped to terminal and interstitial regions of barley (Hordeum vulgare) chromosome 3H, fluorescence in situ hybridization (FISH) on mitotic metaphase chromosomes was performed with 16 genomic single-copy probes derived from fingerprinted BAC contigs. Long genetic distances at subterminal regions translated into short physical distances, confirming that recombination events occur more often at distal regions of chromosome 3H.

Construction of a map-based reference genome sequence for barley, Hordeum vulgare L.

Barley (Hordeum vulgare L.) is a cereal grass mainly used as animal fodder and raw material for the malting industry. The map-based reference genome sequence of barley cv.

A chromosome conformation capture ordered sequence of the barley genome.

Cereal grasses of the Triticeae tribe have been the major food source in temperate regions since the dawn of agriculture. Their large genomes are characterized by a high content of repetitive elements and large pericentromeric regions that are virtually devoid of meiotic recombination. Here we present a high-quality reference genome assembly for barley (Hordeum vulgare L.

Collinearity of homoeologous group 3 chromosomes in the genus Hordeum and Secale cereale as revealed by 3H-derived FISH analysis.

Crop wild relatives are considered as important genetic resources of allelic diversity for domesticated crop species. Their utilization in breeding programs, however, is often limited due to crossing barriers and genome incompatibilities. Wild relatives of barley possess attractive properties and hence allelic diversity for adapting barley better to changing environmental conditions.

A Fast Air-dry Dropping Chromosome Preparation Method Suitable for FISH in Plants.

Preparation of chromosome spreads is a prerequisite for the successful performance of fluorescence in situ hybridization (FISH). Preparation of high quality plant chromosome spreads is challenging due to the rigid cell wall. One of the approved methods for the preparation of plant chromosomes is a so-called drop preparation, also known as drop-spreading or air-drying technique.

Cytogenetic mapping with centromeric bacterial artificial chromosomes contigs shows that this recombination-poor region comprises more than half of barley chromosome 3H.

Genetic maps are based on the frequency of recombination and often show different positions of molecular markers in comparison to physical maps, particularly in the centromere that is generally poor in meiotic recombinations. To decipher the position and order of DNA sequences genetically mapped to the centromere of barley (Hordeum vulgare) chromosome 3H, fluorescence in situ hybridization with mitotic metaphase and meiotic pachytene chromosomes was performed with 70 genomic single-copy probes derived from 65 fingerprinted bacterial artificial chromosomes (BAC) contigs genetically assigned to this recombination cold spot. The total physical distribution of the centromeric 5.