Search bioRxiv⌕ Search
Home/Archive/bioRxiv

bioRxiv · 10.1101/2023.04.27.538624

Workflows for detecting fungicide resistance in net form and spot form net blotch pathogens

Knight, N.·Adhikari, K.·Dodhia, K. N.·Mair, W. J.·Lopez-Ruiz, F. J.
View original source ↗Export metadata ↓

Abstract

Fungicide resistance in Pyrenophora teres f. maculata and P. teres f. teres has become an important disease management issue. Control of the associated barley foliar diseases, spot form and net form net blotch, respectively, relies on three major groups of fungicides, demethylation inhibitors (DMI), succinate dehydrogenase inhibitors (SDHI) and quinone outside inhibitors (QoI). However, resistance has been reported for the DMI and SDHI fungicides in Australia. To enhance detection of different resistance levels, phenotyping and genotyping workflows were designed. The phenotyping workflow generated cultures directly from lesions and compared growth on discriminatory doses of tebuconazole (DMI) and fluxapyroxad (SDHI). Genotyping real-time PCR assays were based on alleles associated with sensitivity or resistance to the DMI and SDHI fungicides. These workflows were applied to a net blotch collection from 2019 consisting predominantly of P. teres f. teres from South Australia and P. teres f. maculata from Western Australia. For South Australia the Cyp51A L489-3 and SdhC-R134 alleles, associated with resistance to tebuconazole and fluxapyroxad, respectively, were the most prevalent. These alleles were frequently found in single isolates with dual resistance. This study also reports the first detection of a 134 base pair insertion located at position -66 (PtTi-6) in the Cyp51A promoter of P. teres f. maculata from South Australia. For Western Australia, the PtTi-1 insertion was the most common allele associated with resistance to tebuconazole. These workflows will be valuable for screening P. teres populations for fungicide resistance, and informing appropriate management strategies.

Source connections

Explore related subjects

pathologyPreprint

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Knight, N., Adhikari, K., Dodhia, K. N., Mair, W. J., Lopez-Ruiz, F. J.. 2023-04-28. Workflows for detecting fungicide resistance in net form and spot form net blotch pathogens. https://doi.org/10.1101/2023.04.27.538624

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

bioRxiv2026

NAE1-Dependent Protein Neddylation Preserves Endothelial Identity and Vascular Integrity

Background: Endothelial dysfunction is a central driver of cardiovascular and inflammatory diseases, yet the post-translational mechanisms that preserve endothelial homeostasis remain incompletely understood. Protein neddylation, the covalent conjugation of a ubiquitin-like modifier, regulates diverse cellular processes, yet its physiological role in the vascular endothelium remains unknown. This study investigated whether protein neddylation is required to preserve endothelial identity and vascular homeostasis. Methods: We generated tamoxifen-inducible endothelial-specific Nae1 knockout mice to inhibit neddylation and combined bulk RNA sequencing, single-cell and single-nucleus transcriptomics, quantitative proteomics, biochemical analyses, and gain- and loss-of-function approaches to define the role of endothelial neddylation in vascular homeostasis and inflammatory injury. Results: Endothelial-specific Nae1 deletion caused rapid mortality associated with vascular leakage, platelet accumulation, inflammation, and multi-organ injury. Multi-omics analyses demonstrated profound loss of endothelial identity, characterized by suppression of core endothelial programs and activation of inflammatory, procoagulant, and pyroptotic pathways. Single-cell analyses revealed progressive endothelial dysfunction culminating in depletion of the endothelial population and remodeling of the vascular niche. Mechanistically, endothelial neddylation deficiency activated gasdermin D (GSDMD)- and gasdermin E (GSDME)-dependent pyroptosis, whereas dual inhibition of GSDMD and GSDME markedly attenuated inflammatory transcriptomic remodeling, vascular injury, hepatocyte death, immune cell infiltration, and platelet accumulation. Translational analyses demonstrated reduced endothelial neddylation in experimental endotoxemia and decreased expression of neddylation pathway components in human atherosclerosis and COVID-19 datasets. Conversely, restoration of endothelial neddylation partially reversed inflammatory endothelial transcriptomic reprogramming in vivo. Conclusions: NAE1-dependent protein neddylation is an essential regulator of endothelial identity and vascular integrity. Loss of endothelial neddylation promotes gasdermin-dependent pyroptosis and thrombo-inflammatory vascular injury, whereas restoration of the neddylation pathway mitigates inflammatory endothelial dysfunction. These findings identify endothelial neddylation as a fundamental mechanism maintaining vascular homeostasis and a potential therapeutic target for cardiovascular and inflammatory diseases.

pathology↗
bioRxiv2024

Co-infection with two iflaviruses (deformed wing virus and sacbrood virus) affects viral and immune dynamics and synergistically increases honey bee mortality

The honey bee microbiome includes a wide variety of viruses. While most of them usually remain commensal, some can become pathogenic in specific contexts. Of these, one is that of deformed wing virus (DWV) and another, sacbrood virus (SBV). Although co-infection is the norm rather than the exception, most of the time these viruses have been studied independently. When investigated as co-infections, past studies have focused on their effects on the honey bee brood. In this study, we co-inoculated adult honey bees at emergence with DWV by injection and SBV orally (acting as the viral transmission by Varroa destructor and by trophallaxis or food, respectively), either simultaneously or sequentially. Using optical counters, we were able to track the survival and behaviour of these honey bees within colonies. Through regular in-hive sampling, we monitored the evolution of their viral loads as well as the expression of eight immune genes involved in honey bee anti-viral immunity. Here, we show that co-inoculations of DWV and SBV synergistically increase the virulence of DWV and conditionally promote the replication of both viruses. Finally, our results show that immune responses in adult honey bees depend on DWV genotypes and whether replication originates from a superinfecting virus or a virus already present in bees. Author SummaryHoney bees are highly social pollinators that live in crowded colonies. Their population density and the high frequency of interactions between individuals favours disease transmission and makes colonies susceptible to pathogen outbreaks. Many viruses commonly infect honey bees, however, they are often studied as single infections. As an effort to better understand interactions between honey bees and multiple viral populations, we co-inoculated young bees with two common honey bee viruses (deformed wing virus and sacbrood virus), released them in colonies and monitored their health and behaviour. Our findings show evidence of synergies between both viruses, as we show that a virus seemingly harmless for adult bees (sacbrood virus) may actually increase the virulence of another virus (deformed wing virus). These results highlight the importance of monitoring and studying multiple pathogens at once for a better understanding of the threat they represent to colony health and survival.

pathology↗
bioRxiv2024

Short-Term Disruption of TGFβ Signaling in Adult Mice Renders the Aorta Vulnerable to Hypertension-Induced Dissection

Hypertension and transient increases in blood pressure from extreme exertion are risk factors for aortic dissection in patients with age-related vascular degeneration or inherited connective tissue disorders. Yet, the common experimental model of angiotensin II-induced aortopathy in mice appears independent of high blood pressure as lesions do not occur in response to an alternative vasoconstrictor, norepinephrine, and are not prevented by co-treatment with a vasodilator, hydralazine. We investigated vasoconstrictor administration to adult mice 1 week after disruption of TGF{beta} signaling in smooth muscle cells. Norepinephrine increased blood pressure and induced aortic dissection by 7 days and even within 30 minutes that was rescued by hydralazine; results were similar with angiotensin II. Changes in regulatory contractile molecule expression were not of pathological significance. Rather, reduced synthesis of extracellular matrix yielded a vulnerable aortic phenotype by decreasing medial collagen, most dynamically type XVIII, and impairing cell-matrix adhesion. We conclude that transient and sustained increases in blood pressure cause dissection in aortas rendered vulnerable by inhibition of TGF{beta}-driven extracellular matrix production by smooth muscle cells. A corollary is that medial fibrosis, a frequent feature of medial degeneration, may afford some protection against aortic dissection.

pathology↗