First report of causing Phomopsis stem canker on sunflower ( L.) in Minnesota.

Cultivated sunflower (Helianthus annuus L.) is a globally important oilseed crop that is grown primarily in the Northern Great Plains region of the United States. In September 2018, sunflower stems exhibiting brown stem lesions centered on the leaf axils and accompanied by pith degradation, consistent with symptoms of Phomopsis stem canker (PSC) disease, were sampled from a commercial field of approximately 520 hectares in Polk County, MN (47°50'24" N, 96.

Multiple Forms of Resistance to the Phomopsis Stem Canker Pathogens and in Sunflower.

Phomopsis stem canker of cultivated sunflower ( L.) can be caused by multiple necrotrophic fungi in the genus , with and being the most common causal agents in the United States. Infection begins at the leaf margins and proceeds primarily through the vasculature, progressing from the leaf through the petiole to the stem, resulting in formation of brown stem lesions centered around the petiole.

Heritable differences in abundance of bacterial rhizosphere taxa are correlated with fungal necrotrophic pathogen resistance.

Host-microbe interactions are increasingly recognized as important drivers of organismal health, growth, longevity and community-scale ecological processes. However, less is known about how genetic variation affects hosts' associated microbiomes and downstream phenotypes. We demonstrate that sunflower (Helianthus annuus) harbours substantial, heritable variation in microbial communities under field conditions.

Genetic analysis of basal stalk rot resistance introgressed from wild into cultivated sunflower ( L.) using an advanced backcross population.

Introduction: is a serious pathogen causing severe basal stalk rot (BSR) disease on cultivated sunflower ( L.) that leads to significant yield losses due to insufficient resistance. The wild annual sunflower species , commonly known as prairie sunflower is known for its resistance against this pathogen.

Population and genome-wide association studies of isolates collected from diverse host plants throughout the United States.

Introduction: Sclerotinia sclerotiorum is a necrotrophic fungal pathogen causing disease and economic loss on numerous crop plants. This fungus has a broad host range and can infect over 400 plant species, including important oilseed crops such as soybean, canola, and sunflower. S.

Mutation and sequencing-based cloning and functional studies of a rust resistance gene in sunflower (Helianthus annuus).

Rust, caused by the fungus Puccinia helianthi Schwein., is one of the most devastating diseases of sunflower (Helianthus annuus L.), affecting global production.

A Quantitative Genetic Study of Sclerotinia Head Rot Resistance Introgressed from the Wild Perennial into Cultivated Sunflower ( L.).

Sclerotinia head rot (HR), caused by Sclerotinia sclerotiorum, is an economically important disease of sunflower with known detrimental effects on yield and quality in humid climates worldwide. The objective of this study was to gain insight into the genetic architecture of HR resistance from a sunflower line HR21 harboring HR resistance introgressed from the wild perennial Helianthus maximiliani. An F2 population derived from the cross of HA 234 (susceptible-line)/HR21 (resistant-line) was evaluated for HR resistance at two locations during 2019−2020.

Genomic Insights Into Sclerotinia Basal Stalk Rot Resistance Introgressed From Wild Into Cultivated Sunflower ( L.).

Crop wild relatives of the cultivated sunflower ( L.) are a valuable resource for its sustainable production. ssp.

GOLD36/MVP1/ERMO3 Is Required for Powdery Mildew Penetration Resistance and Proper Targeting of the PEN3 Transporter.

The PENETRATION 3 (PEN3) ATP binding cassette (ABC) transporter contributes to penetration resistance against nonadapted powdery mildew fungi and is targeted to papillae deposited at sites of interaction with the fungus. Timely recruitment of PEN3 and other components of penetration resistance to the host-pathogen interface is important for successful defense against this biotrophic pathogen. A forward genetic screen was previously carried out to identify mutants that mistarget the PEN3 transporter or fail to accumulate PEN3 at sites of attempted powdery mildew penetration.

Multiple Species of Asteraceae Plants Are Susceptible to Root Infection by the Necrotrophic Fungal Pathogen .

The necrotrophic fungal pathogen can cause disease on numerous plant species, including many important crops. Most -incited diseases of crop plants are initiated by airborne ascospores produced when fungal sclerotia germinate to form spore-bearing apothecia. However, basal stalk rot of sunflower occurs when sclerotia germinate to form mycelia within the soil, which subsequently invade sunflower roots.

Unraveling the Basal Stalk Rot Resistance Derived From Wild Using a High-Density Single Nucleotide Polymorphism Linkage Map.

Basal stalk rot (BSR), caused by the fungus , is a serious disease of sunflower ( L.) in the humid temperate growing areas of the world. BSR resistance is quantitative and conditioned by multiple genes.

A Greenhouse Method to Evaluate Sunflower Quantitative Resistance to Basal Stalk Rot Caused by .

Resistance of sunflower to basal stalk rot (BSR) caused by the fungus is quantitative, controlled by multiple genes contributing small effects. Consequently, artificial inoculation procedures allowing sufficient throughput and resolution of resistance are needed to identify highly resistant sunflower germplasm resources and to map loci contributing to resistance. The objective of this study was to develop a greenhouse-based method for evaluating sunflower quantitative resistance to BSR that would be simple, space- and time-efficient, high throughput, high resolution, and correlated with field observations.

Determination of Virulence Phenotypes of in the United States.

Downy mildew, caused by (Farl.) Berl. and de Toni, is an economically important disease in cultivated sunflowers, L.

Genetic Dissection of Phomopsis Stem Canker Resistance in Cultivated Sunflower Using High Density SNP Linkage Map.

Phomopsis stem canker (PSC) caused by is increasingly becoming a global threat for sunflower production. In this study, the genetic basis of PSC resistance was investigated in a recombinant inbred line (RIL) population developed from a cross between HA 89 (susceptible) and HA-R3 (resistant). The RIL population was evaluated for PSC disease incidence (DI) in seven screening trials at multiple locations during 2016-2018.

Molecular dissection of resistance gene cluster and candidate gene identification of Pl and Pl in sunflower by whole-genome resequencing.

Sunflower (Helianthus annuus L.) production is challenged by different biotic and abiotic stresses, among which downy mildew (DM) is a severe biotic stress that is detrimental to sunflower yield and quality in many sunflower-growing regions worldwide. Resistance against its infestation in sunflower is commonly regulated by single dominant genes.

PMR5, an acetylation protein at the intersection of pectin biosynthesis and defense against fungal pathogens.

Powdery mildew (Golovinomyces cichoracearum), one of the most prolific obligate biotrophic fungal pathogens worldwide, infects its host by penetrating the plant cell wall without activating the plant's innate immune system. The Arabidopsis mutant powdery mildew resistant 5 (pmr5) carries a mutation in a putative pectin acetyltransferase gene that confers enhanced resistance to powdery mildew. Here, we show that heterologously expressed PMR5 protein transfers acetyl groups from [ C]-acetyl-CoA to oligogalacturonides.

Introgression and monitoring of wild Helianthus praecox alien segments associated with Sclerotinia basal stalk rot resistance in sunflower using genotyping-by-sequencing.

Sclerotinia basal stalk rot (BSR) and downy mildew are major diseases of sunflowers worldwide. Breeding for BSR resistance traditionally relies upon cultivated sunflower germplasm that has only partial resistance thus lacking an effective resistance against the pathogen. In this study, we report the transfer of BSR resistance from sunflower wild species, Helianthus praecox, into cultivated sunflower and molecular assessment of the introgressed segments potentially associated with BSR resistance using the genotyping-by-sequencing (GBS) approach.

Follicular lymphoma presenting as scalp mass deformity: Case Report and Review of the literature.

Lymphoma presenting as a scalp mass is a rare but serious medical condition mandating aggressive treatment and neurosurgical intervention. We report a case of 53-year-old male who presented with a large right sided frontal scalp mass and a smaller mass located on the left frontal scalp. After discussion with the patient, it was decided to resect the larger mass for definitive diagnosis.

Phosphorylation is required for the pathogen defense function of the Arabidopsis PEN3 ABC transporter.

The Arabidopsis PEN3 ABC transporter accumulates at sites of pathogen detection, where it is involved in defense against a number of pathogens. Perception of PAMPs by pattern recognition receptors initiates recruitment of PEN3 and also leads to PEN3 phosphorylation at multiple amino acid residues. Whether PAMP-induced phosphorylation of PEN3 is important for its defense function or focal recruitment has not been addressed.

Purification of High Molecular Weight Genomic DNA from Powdery Mildew for Long-Read Sequencing.

The powdery mildew fungi are a group of economically important fungal plant pathogens. Relatively little is known about the molecular biology and genetics of these pathogens, in part due to a lack of well-developed genetic and genomic resources. These organisms have large, repetitive genomes, which have made genome sequencing and assembly prohibitively difficult.

An Arabidopsis Lipid Flippase Is Required for Timely Recruitment of Defenses to the Host-Pathogen Interface at the Plant Cell Surface.

Deposition of cell wall-reinforcing papillae is an integral component of the plant immune response. The Arabidopsis PENETRATION 3 (PEN3) ATP binding cassette (ABC) transporter plays a role in defense against numerous pathogens and is recruited to sites of pathogen detection where it accumulates within papillae. However, the trafficking pathways and regulatory mechanisms contributing to recruitment of PEN3 and other defenses to the host-pathogen interface are poorly understood.

Contributions of host cellular trafficking and organization to the outcomes of plant-pathogen interactions.

In recent years it has become increasingly apparent that dynamic changes in protein localization, membrane trafficking pathways, and cellular organization play a major role in determining the outcome of interactions between plants and pathogenic microorganisms. Plants have evolved sophisticated perception systems to recognize the presence of potentially pathogenic microorganisms via the detection of non-self or modified-self elicitor molecules, pathogen virulence factors, or the activities of such virulence factors. Dynamic changes to host cellular organization and membrane trafficking pathways play pivotal roles in detection and signaling by plant immune receptors and are vital for the execution of spatially targeted defense responses to thwart invasion by potential pathogens.

Perception of conserved pathogen elicitors at the plasma membrane leads to relocalization of the Arabidopsis PEN3 transporter.

The Arabidopsis penetration resistance 3 (PEN3) ATP binding cassette transporter participates in nonhost resistance to fungal and oomycete pathogens and is required for full penetration resistance to the barley powdery mildew Blumeria graminis f. sp. hordei.

Induction and suppression of PEN3 focal accumulation during Pseudomonas syringae pv. tomato DC3000 infection of Arabidopsis.

The pleiotropic drug resistance (PDR) proteins belong to the super-family of ATP-binding cassette (ABC) transporters. AtPDR8, also called PEN3, is required for penetration resistance of Arabidopsis to nonadapted powdery mildew fungi. During fungal infection, plasma-membrane-localized PEN3 is concentrated at fungal entry sites, as part of the plant's focal immune response.

The plant cell wall: a dynamic barrier against pathogen invasion.

Prospective plant pathogens must overcome the physical barrier presented by the plant cell wall. In addition to being a preformed, passive barrier limiting access of pathogens to plant cells, the cell wall is actively remodeled and reinforced specifically at discrete sites of interaction with potentially pathogenic microbes. Active reinforcement of the cell wall through the deposition of cell wall appositions, referred to as papillae, is an early response to perception of numerous categories of pathogens including fungi and bacteria.