scholarly journals The barley HvSTP13GR mutant triggers resistance against biotrophic fungi

2021 ◽  
Author(s):  
Caroline Ines Skoppek ◽  
Wilko Punt ◽  
Marleen Heinrichs ◽  
Frank Ordon ◽  
Gwendolin Wehner ◽  
...  
Keyword(s):  
Biotrophic Fungi

Effectors of biotrophic fungal plant pathogens

2010 ◽  
Vol 37 (10) ◽  
pp. 913 ◽  
Author(s):  
Pamela H. P. Gan ◽  
Maryam Rafiqi ◽  
Adrienne R. Hardham ◽  
Peter N. Dodds
Keyword(s):  
Plant Tissue ◽  
Fungal Pathogen ◽  
Plant Pathogens ◽  
Plant Cells ◽  
Host Cells ◽  
Plant Proteins ◽  
Living Plant ◽  
Host Cytoplasm ◽  
Fungal Plant Pathogens ◽  
Biotrophic Fungi

Plant pathogenic biotrophic fungi are able to grow within living plant tissue due to the action of secreted pathogen proteins known as effectors that alter the response of plant cells to pathogens. The discovery and identification of these proteins has greatly expanded with the sequencing and annotation of fungal pathogen genomes. Studies to characterise effector function have revealed that a subset of these secreted pathogen proteins interact with plant proteins within the host cytoplasm. This review focuses on the effectors of intracellular biotrophic and hemibiotrophic fungal plant pathogens and summarises advances in understanding the roles of these proteins in disease and in elucidating the mechanism of fungal effector uptake into host cells.

The Barley HvSTP13GR mutant triggers resistance against biotrophic fungi

2021 ◽  
Author(s):  
Caroline Ines Skoppek ◽  
Wilko Punt ◽  
Marleen Heinrichs ◽  
Frank Ordon ◽  
Gwendolin Wehner ◽  
...  
Keyword(s):  
Plant Protection ◽  
Rust Fungus ◽  
Durable Resistance ◽  
Sugar Transport ◽  
Gene Promoter ◽  
Monosaccharide Transporter ◽  
Base Editing ◽  
Biological Stress ◽  
Biotrophic Fungi ◽  
Promoter Studies

High-yielding and stress resistant crops are essential to ensure future food supply. Barley is an important crop to feed livestock and to produce malt, but the annual yield is threatened by pathogen infections. Pathogens can trigger an altered sugar partitioning in the host plant, that possibly leads to an advantage for the pathogen. Hampering these processes represents a promising strategy to potentially increase resistance. We analyzed the response of the barley monosaccharide transporter HvSTP13 towards biotic stress and its potential use for plant protection. The expression of HvSTP13 increased upon bacterial and fungal PAMP application, suggesting a PAMP-triggered signaling that converged on the transcriptional induction of the gene. Promoter studies indicate a region that is likely targeted by transcription factors downstream of PAMP-triggered immunity pathways. We confirmed that the non-functional HvSTP13GR variant confers resistance against an economically relevant biotrophic rust fungus, in barley. In addition, we established targeted CRISPR/Cas9 cytosine base editing in barley protoplasts to generate alternative HvSTP13 mutants and characterized the sugar transport activity and subcellular localization of the proteins. These mutants represent promising variants for future resistance analysis. Our experimental setup provides basal prerequisites to further decode the role of HvSTP13 in response to biological stress. Moreover, in line with other studies, our experiments indicate that the alteration of sugar partitioning pathways, in a host pathogen interaction, is a promising approach to achieve broad and durable resistance in plants.

A Hyperspectral Library of Foliar Diseases of Wheat

2021 ◽  
Author(s):  
David Bohnenkamp ◽  
Jan Behmann ◽  
Stefan Paulus ◽  
Ulrike Steiner ◽  
Anne-Katrin Mahlein
Keyword(s):  
Developmental Stages ◽  
Leaf Tissue ◽  
Plant Diseases ◽  
Identification System ◽  
Spectral Library ◽  
Foliar Diseases ◽  
Robust Detection ◽  
Analysis Methods ◽  
Detection And Identification ◽  
Biotrophic Fungi

This work established a hyperspectral library of important foliar diseases of wheat in time series to detect spectral changes from infection to symptom appearance induced by different pathogens. The data was generated under controlled conditions at the leaf-scale. The transition from healthy to diseased leaf tissue was assessed, spectral shifts were identified and used in combination with histological investigations to define developmental stages in pathogenesis for each disease. The spectral signatures of each plant disease that are indicative of a certain developmental stage during pathogenesis - defined as turning points - were combined into a spectral library. Different machine learning analysis methods were applied and compared to test the potential of this library for the detection and quantification of foliar diseases in hyperspectral images. All evaluated classifiers provided a high accuracy for the detection and identification for both the biotrophic fungi and the necrotrophic fungi of up to 99%. The potential of applying spectral analysis methods, in combination with a spectral library for the detection and identification of plant diseases is demonstrated. Further evaluation and development of these algorithms should contribute to a robust detection and identification system for plant diseases at different developmental stages and the promotion and development of site-specific management techniques of plant diseases under field conditions.

scholarly journals SsPEP1, an Effector with Essential Cellular Functions in Sugarcane Smut Fungus

2021 ◽  
Vol 7 (11) ◽  
pp. 954
Author(s):  
Shan Lu ◽  
Yukun Wang ◽  
Xiaorui Shen ◽  
Feng Guo ◽  
Chunling Zhou ◽  
...  
Keyword(s):  
Potent Inhibitor ◽  
Mapk Signaling ◽  
Symptom Development ◽  
Cellular Functions ◽  
Sporisorium Scitamineum ◽  
Expression Of Genes ◽  
Allele Dosage ◽  
Biotrophic Fungi ◽  
Related Stress ◽  
Important Disease

Biotrophic fungi have to infect their host to obtain nutrients and must establish an interaction with the host to complete their life cycle. In this process, effectors play important roles in manipulating the host’s immune system to avoid being attacked. Sporisorium scitamineum is the causative agent of sugarcane smut, the most important disease in sugarcane-producing regions worldwide. In this work, we functionally characterized the conserved effector PEP1 in S. scitamineum. The mating process and the expression of genes in the MAPK signaling pathway and the a and b loci were adversely affected in Sspep1-null mutants. The requirement for SsPEP1 in pathogenicity and symptom development was allele dosage-dependent, i.e., deleting one Sspep1 allele in the mating pair turned a normal black whip with abundant teliospores into a white whip with few teliospores; however, deleting both alleles almost abolished infectivity and whip development. ΔSspep1 mutants produced significantly less mycelium mass within infected plants. Additionally, SsPEP1 was identified as a potent inhibitor of sugarcane POD-1a peroxidase activity, implying that SsPEP1 may function to relieve reactive oxygen species-related stress within the host plant. Taken together, our work demonstrated that SsPEP1 is a multifaceted effector essential for S. scitamineum growth, development, and pathogenicity.

scholarly journals Development and Evaluation of Laboratory Bioassays to Study Powdery Mildew Pathogens of Phlox In Vitro

Plant Disease ◽  
2019 ◽  
Vol 103 (7) ◽  
pp. 1536-1543 ◽  
Author(s):  
Coralie Farinas ◽  
Pablo Jourdan ◽  
Pierce A. Paul ◽  
Francesca Peduto Hand
Keyword(s):  
Powdery Mildew ◽  
Ornamental Plants ◽  
Fungal Growth ◽  
Ms Medium ◽  
Adaxial Side ◽  
Single Spore ◽  
Experimental Conditions ◽  
Inoculation Techniques ◽  
Biotrophic Fungi

The genus Phlox consists of approximately 65 species that include some of the most prevalent ornamental plants in the temperate zone. These popular ornamentals are extremely susceptible to powdery mildew (PM) caused by the biotrophic fungi Golovinomyces magnicellulatus and Podosphaera sp. In this study, we used Phlox paniculata and P. glaberrima to develop a set of laboratory tools to study these pathogens in vitro, including a detached leaf and a micropropagated plantlet bioassay. We assessed pathogen growth under different experimental conditions, which included the use of four different media variations (1/2 MS medium amended with benzimidazole and tetracycline), three ages of pathogen culture (14, 18, and 22 days), three phenological stages of the host tissue (1st, 3rd, and 5th node leaves), placement of inoculum on both leaf surfaces (abaxial and adaxial), and three different inoculation techniques (single spore transfer, colony tapping, colony brushing). Detached P. paniculata leaves were successfully maintained on benzimidazole-amended 1/2 MS medium for up to 3 weeks. For both pathogens, the use of 18-day-old cultures resulted in a higher number of larger, higher sporulating colonies compared with 1-4 and 22-day-old cultures. The adaxial side of 3rd node leaves supported statistically significant more fungal growth compared with the adaxial side of 1st and 5th node leaves. Both pathogens also successfully infected micropropagated plantlets of P. glaberrima. These newly developed tools should facilitate in vitro studies on PM of Phlox and possibly be applicable to other ornamental species attacked by the same fungi.

scholarly journals Secondary metabolites synthesized by Stemphylium lycopersici and Fulvia fulva, necrotrophic and biotrophic fungi pathogen of tomato plants

2019 ◽  
Vol 20 ◽  
pp. 100122 ◽  
Author(s):  
Rocio Medina ◽  
Mario E.E. Franco ◽  
César G. Lucentini ◽  
Janina A. Rosso ◽  
Mario C.N. Saparrat ◽  
...  
Keyword(s):  
Secondary Metabolites ◽  
Tomato Plants ◽  
Stemphylium Lycopersici ◽  
Fulvia Fulva ◽  
Biotrophic Fungi

scholarly journals THE ACTIVITY OF INVERTASE AND ITS RELEVANCE TO THE ACCUMULATION OF STORAGE POLYSACCHARIDES IN LEAVES INFECTED BY BIOTROPHIC FUNGI

1975 ◽  
Vol 74 (2) ◽  
pp. 173-182 ◽  
Author(s):  
D. E. LONG ◽  
A. K. FUNG ◽  
E. E. M. McGEE ◽  
R. C. COOKE ◽  
D. H. LEWIS
Keyword(s):  
Biotrophic Fungi ◽  
Storage Polysaccharides

scholarly journals Understanding the lifestyles and pathogenicity mechanisms of obligate biotrophic fungi in wheat: The emerging genomics era

2018 ◽  
Vol 6 (1) ◽  
pp. 60-67 ◽  
Author(s):  
Chunlei Tang ◽  
Qiang Xu ◽  
Mengxin Zhao ◽  
Xiaojie Wang ◽  
Zhensheng Kang
Keyword(s):  
Biotrophic Fungi

scholarly journals Soil stabilisation for DNA metabarcoding of plants and fungi. Implications for sampling at remote locations or via third-parties

2020 ◽  
Vol 4 ◽  
Author(s):  
Lina A. Clasen ◽  
Andrew P. Detheridge ◽  
John Scullion ◽  
Gareth W. Griffith
Keyword(s):  
Freeze Drying ◽  
Storage Conditions ◽  
Third Parties ◽  
Stochastic Variation ◽  
Saprotrophic Fungi ◽  
Soil Stabilisation ◽  
Dna Metabarcoding ◽  
Biotrophic Fungi ◽  
Storage Methods ◽  
Initial Freezing

Storage of soil samples prior to metagenomic analysis presents a problem. If field sites are remote or if samples are collected by third parties, transport to analytical laboratories may take several days or even weeks. The bulk of such samples and requirement for later homogenisation precludes the convenient use of a stabilisation buffer, so samples are usually cooled or frozen during transit. There has been limited testing of the most appropriate storage methods for later study of soil organisms by eDNA approaches. Here we tested a range of storage methods on two contrasting soils, comparing these methods to the control of freezing at -80 °C, followed by freeze-drying. To our knowledge, this is the first study to examine the effect of storage conditions on eukaryote DNA in soil, including both viable organisms (fungi) and DNA contained within dying/dead tissues (plants). For fungi, the best storage regimes (closest to the control) were storage at 4 °C (for up to 14 d) or active air-drying at room temperature. The worst treatments involved initial freezing, followed by thawing which led to significant later spoilage. The key spoilage organisms were identified as Metarhizium carneum and Mortierella spp., with a general increase in saprotrophic fungi and reduced abundances of mycorrhizal/biotrophic fungi. Plant data showed a similar pattern, but with greater variability in community structure, especially in the freeze-thaw treatments, probably due to stochastic variation in substrates for fungal decomposition, algal proliferation and some seed germination. In the absence of freeze drying facilities, samples should be shipped refrigerated, but not frozen if there is any risk of thawing.

scholarly journals Real-Time PCR-Based Monitoring of DNA Pools in the Tri-Trophic Interaction Between Norway Spruce, the Rust Thekopsora areolata, and an Opportunistic Ascomycetous Phomopsis sp.

2008 ◽  
Vol 98 (1) ◽  
pp. 51-58 ◽  
Author(s):  
Ari M. Hietala ◽  
Halvor Solheim ◽  
Carl Gunnar Fossdal
Keyword(s):  
Real Time ◽  
Norway Spruce ◽  
Plant Diseases ◽  
Separate Analysis ◽  
Latent Stage ◽  
Phloem Necrosis ◽  
Biotrophic Fungi ◽  
Polymerase Chain ◽  
Internal Transcribed Spacer Rdna ◽  
Very High

The difficulty in subculturing biotrophic fungi complicates etiological studies related to the associated plant diseases. By employing internal transcribed spacer rDNA-targeted quantitative real-time polymerase chain reaction, we now show that the heteroecious rust Thekopsora areolata, commonly associated in natural conditions to sapling shoots and cones of Norway spruce and leaves of wild bird cherry, frequently infects nursery-grown seedlings of the conifer. A spatial sampling scheme was used to investigate seedlings and saplings of Norway spruce showing phloem necrosis: the highest concentration of DNA of T. areolata was recorded in the area with necrotic phloem. The separate analysis of bark and wood tissues suggested that the initial spread of the rust to healthy tissues neighboring the infection site takes place in the bark. A Phomopsis species found to coexist with T. areolata in several seedlings showed very high DNA levels in the upper part of the lesion, and even in the visually healthy proximal tissues above the lesions, which indicates that the ascomycete, most probably a secondary invader following primary infection by T. areolata, has a latent stage during early host colonization. We hypothesize that this hemibiotrophic mode of infection contributes to the successful coexistence of Phomopsis with a biotrophic rust.

Sign in / Sign up

Export Citation Format

Share Document