A LysM Effector Mediates Adhesion and Plant Immunity Suppression in the Necrotrophic Fungus Botrytis cinerea.

LysM effectors are suppressors of chitin-triggered plant immunity in biotrophic and hemibiotrophic fungi. In necrotrophic fungi, LysM effectors might induce a mechanism to suppress host immunity during the short asymptomatic phase they establish before these fungi activate plant defenses and induce host cell death leading to necrosis. Here, we characterize a secreted LysM protein from a major necrotrophic fungus, Botrytis cinerea, called BcLysM1.

Evaluation of cell death-inducing activity of spp. effectors in several plants using a modified TRV expression system.

Introduction: Brown rot is the most important fungal disease affecting stone fruit and it is mainly caused by , and . spp. are necrotrophic plant pathogens with the ability to induce plant cell death by the secretion of different phytotoxic molecules, including proteins or metabolites that are collectively referred to as necrotrophic effectors (NEs).

Baking bad: plants in a toasty world with necrotrophs.

Rising global temperatures pose a threat to plant immunity, making them more susceptible to diseases. The impact of temperature on plant immunity against biotrophic and hemi-biotrophic pathogens is well documented, while its effect on necrotrophs remains poorly understood. We venture into the uncharted territory of necrotrophic fungal pathogens in the face of rising temperatures.

Genome Comparisons between and the Closely Related Gray Mold Fungus Reveal Possible Explanations for Their Contrasting Host Ranges.

While causes gray mold on many plants, its close relative, , is host-specifically infecting predominantly faba bean plants. To explore the basis for its narrow host range, a gapless genome sequence of strain G12 (BfabG12) was generated. The BfabG12 genome encompasses 45.

Leaf resistance to in wild tomato depends on inoculum composition.

Tomato (S) cv. Moneymaker (MM) is very susceptible to the grey mould , while quantitative resistance in the wild species (accession LYC4) has been reported. In leaf inoculation assays, an effect of nutrient and spore concentration on disease incidence was observed.

Molecular characterization of cross-kingdom RNA interference in by tomato small RNAs.

Previous studies have suggested that plants can modulate gene expression in pathogenic fungi by producing small RNAs (sRNAs) that can be translocated into the fungus and mediate gene silencing, which may interfere with the infection mechanism of the intruder. We sequenced sRNAs and mRNAs in early phases of the (tomato)- interaction and examined the potential of plant sRNAs to silence their predicted mRNA targets in the fungus. Almost a million unique plant sRNAs were identified that could potentially target 97% of all fungal genes.

Analysis of plant cell death-inducing proteins of the necrotrophic fungal pathogens and .

Fungal plant pathogens secrete proteins that manipulate the host in order to facilitate colonization. Necrotrophs have evolved specialized proteins that actively induce plant cell death by co-opting the programmed cell death machinery of the host. Besides the broad host range pathogen , most other species within the genus are restricted to a single host species or a group of closely related hosts.

Molecular characterization reveals no functional evidence for naturally occurring cross-kingdom RNA interference in the early stages of Botrytis cinerea-tomato interaction.

Plant immune responses are triggered during the interaction with pathogens. The fungus Botrytis cinerea has previously been reported to use small RNAs (sRNAs) as effector molecules capable of interfering with the host immune response. Conversely, a host plant produces sRNAs that may interfere with the infection mechanism of an intruder.

Botrytis cinerea infection accelerates ripening and cell wall disassembly to promote disease in tomato fruit.

Postharvest fungal pathogens benefit from the increased host susceptibility that occurs during fruit ripening. In unripe fruit, pathogens often remain quiescent and unable to cause disease until ripening begins, emerging at this point into destructive necrotrophic lifestyles that quickly result in fruit decay. Here, we demonstrate that one such pathogen, Botrytis cinerea, actively induces ripening processes to facilitate infections and promote disease in tomato (Solanum lycopersicum).

The association between the susceptibility to Botrytis cinerea and the levels of volatile and non-volatile metabolites in red ripe strawberry genotypes.

The relations between physical and chemical characteristics (e.g., color, firmness, volatile and non-volatile metabolites) of red ripe strawberry fruit and the natural spoilage caused by Botrytis cinerea were investigated.

Cytotoxic activity of Nep1-like proteins on monocots.

Necrosis- and ethylene-inducing peptide 1 (Nep1)-like proteins (NLPs) are found throughout several plant-associated microbial taxa and are typically considered to possess cytolytic activity exclusively on dicot plant species. However, cytolytic NLPs are also produced by pathogens of monocot plants such as the onion (Allium cepa) pathogen Botrytis squamosa. We determined the cytotoxic activity of B.

Distinct immune sensor systems for fungal endopolygalacturonases in closely related Brassicaceae.

Plant pattern recognition receptors (PRRs) facilitate recognition of microbial patterns and mediate activation of plant immunity. Arabidopsis thaliana RLP42 senses fungal endopolygalacturonases (PGs) and triggers plant defence through complex formation with SOBIR1 and SERK co-receptors. Here, we show that a conserved 9-amino-acid fragment pg9(At) within PGs is sufficient to activate RLP42-dependent plant immunity.

Fire Blight Susceptibility in spp. Correlates to Sensitivity to Secreted Cell Death Inducing Compounds.

Fire blight represents a widespread disease in spp. and is caused by the necrotrophic Ascomycete . There are >100 species that fall into distinct phylogenetic groups and these have been used to generate the contemporary commercial genotypes.

Comparative Genomics Used to Predict Virulence Factors and Metabolic Genes among Species.

Brown rot, caused by spp., is among the most important diseases in stone fruits, and some pome fruits (mainly apples). This disease is responsible for significant yield losses, particularly in stone fruits, when weather conditions favorable for disease development appear.

A Major Effect Gene Controlling Development and Pathogenicity in Identified Through Genetic Analysis of Natural Mycelial Non-pathogenic Isolates.

is a necrotrophic plant pathogenic fungus with a wide host range. Its natural populations are phenotypically and genetically very diverse. A survey of isolates causing gray mold in the vineyards of Castilla y León, Spain, was carried out and as a result eight non-pathogenic natural variants were identified.

Deciphering the Genome to Discover Effector Genes Possibly Involved in Virulence.

Brown rot is the most economically important fungal disease of stone fruits and is primarily caused by and . Both species co-occur in European orchards although is considered to cause the most severe yield losses in stone fruit. This study aimed to generate a high-quality genome of and to exploit it to identify genes that may contribute to pathogen virulence.

Visualization of Three Sclerotiniaceae Species Pathogenic on Onion Reveals Distinct Biology and Infection Strategies.

, , and are three fungal species of the family Sclerotiniaceae that are pathogenic on onion. Despite their close relatedness, these fungi cause very distinct diseases, respectively called leaf blight, neck rot, and white rot, which pose serious threats to onion cultivation. The infection biology of neck rot and white rot in particular is poorly understood.

Dynamics in Secondary Metabolite Gene Clusters in Otherwise Highly Syntenic and Stable Genomes in the Fungal Genus Botrytis.

Fungi of the genus Botrytis infect >1,400 plant species and cause losses in many crops. Besides the broad host range pathogen Botrytis cinerea, most other species are restricted to a single host. Long-read technology was used to sequence genomes of eight Botrytis species, mostly pathogenic on Allium species, and the related onion white rot fungus, Sclerotium cepivorum.

Bitter and sweet make tomato hard to (b)eat.

The glycoalkaloid saponin α-tomatine is a tomato-specific secondary metabolite that accumulates to millimolar levels in vegetative tissues and has antimicrobial and antinutritional activity that kills microbial pathogens and deters herbivorous insects. We describe recent insights into the biosynthetic pathway of α-tomatine synthesis and its regulation. We discuss the mode of action of α-tomatine by physically interacting with sterols, thereby disrupting membranes, and how tomato protects itself from its toxic action.

Peeling the Onion: Towards a Better Understanding of Diseases of Onion.

Onion is cultivated worldwide for its bulbs, but production is threatened by pathogens and pests. Three distinct diseases of onion are caused by species that belong to the fungal genus Leaf blight is a well-known foliar disease caused by that can cause serious yield losses. Neck rot is a postharvest disease that manifests in bulbs after storage and is associated with three species: , , and .

Grey mould of strawberry, a devastating disease caused by the ubiquitous necrotrophic fungal pathogen Botrytis cinerea.

The fungal pathogen Botrytis cinerea causes grey mould, a commercially damaging disease of strawberry. This pathogen affects fruit in the field, storage, transport and market. The presence of grey mould is the most common reason for fruit rejection by growers, shippers and consumers, leading to significant economic losses.