Validation of high-throughput real time polymerase chain reaction assays for simultaneous detection of invasive citrus pathogens

A quantitative real-time polymerase chain reaction (qPCR) was developed and validated for quantification of Venturia inaequalis in infected leaf tissue of Malus × domestica. The method is based on dual-labeled hybridization probes, allowing simultaneous detection of host and pathogen DNA within one single reaction. Limit of quantification for the pathogen was 0.5 pg per reaction and, for the host, reached 5 pg per reaction. The fungal growth measured in four apple cultivars 2 weeks after inoculation significantly correlated with their different level of scab resistance and allowed the observation of ontogenic resistance. After sporulation on the youngest leaf, fungal biomass in susceptible ‘Gala’ was 118 times higher than in resistant ‘Florina’ and ‘Discovery’ while intermediate values were found with the intermediate susceptible ‘Milwa’. Correlation was also observed between severity classes obtained by visual scoring of symptoms and qPCR results. Moreover, qPCR demonstrated validity of the developed method as a disease severity forecast tool 10 days after the pathogen's inoculation and prior to the appearance of the symptoms. Applications of the methodology can include the quantification of scab resistance during breeding programs, evaluation of fungicide and biocontrol efficacy, and quantification of the fitness of different pathogenic strains.

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Development of multiplex real‐time reverse‐transcriptase polymerase chain reaction assay for simultaneous detection of Zika, dengue, yellow fever, and chikungunya viruses in a single tube

Journal of Medical Virology ◽

10.1002/jmv.25253 ◽

2018 ◽

Vol 90 (11) ◽

pp. 1681-1686 ◽

Cited By ~ 10

Author(s):

Wenhui Wu ◽

Jin Wang ◽

Nan Yu ◽

Juying Yan ◽

Zhihao Zhuo ◽

...

Keyword(s):

Polymerase Chain Reaction ◽

Reverse Transcriptase ◽

Real Time ◽

Yellow Fever ◽

Polymerase Chain Reaction Assay ◽

Simultaneous Detection ◽

Chain Reaction ◽

Single Tube ◽

Polymerase Chain

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A Duplex SYBR Green I-based Real-time Polymerase Chain Reaction Assay for Rapid Detection of Canine Kobuvirus and Canine Circovirus

10.21203/rs.3.rs-960132/v1 ◽

2021 ◽

Author(s):

Yang Pan ◽

Jing Chen ◽

Junhuang Wu ◽

Yongxia Wang ◽

Junwei Zou ◽

...

Keyword(s):

Polymerase Chain Reaction ◽

Real Time ◽

Rapid Detection ◽

Simultaneous Detection ◽

Sybr Green ◽

Sybr Green I ◽

Chain Reaction ◽

Pcr Assay ◽

Polymerase Chain ◽

Canine Kobuvirus

Abstract Background: Canine Kobuvirus (CaKoV) and Canine Circovirus (CaCV) are viruses that infect dogs causing diarrheal symptoms that are very similar. However, there is no clinical method to detect a co-infection of these two viruses.Results: In this study, a duplex SYBR Green I-based quantitative real-time polymerase chain reaction (PCR) assay for the rapid and simultaneous detection of CaKoV and CaCV was established. CaKoV and CaCV were distinguished by their different melting temperature which was 86℃ for CaKoV and 78℃ for CaCV. The assay was highly specific, with no cross-reactivity with other common canine viruses and demonstrated high sensitivity. The detection limits of CaKoV and CaCV were 8.924 × 101 copies/μL and 3.841 × 101 copies/μL, respectively. The highest intra- and inter-assay Ct value variation coefficients (CV) of CaKoV were 0.40% and 0.96%, respectively. For CaCV, the highest intra- and inter-assay Ct value variation coefficients were 0.26% and 0.70%, respectively. In 57 clinical samples, positive detection rates of CaKoV and CaCV were 8.77% (7/57) and 15.79% (9/57), respectively. The co-infection rate was 7.02% (4/57). Conclusions: The duplex SYBR Green I-based real-time PCR assay established in this study is a fast, efficient, and sensitive method for the simultaneous detection of the two viruses and provides a powerful tool for the rapid detection of CaKoV and CaCV in clinical practice.

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Evaluation of a 384–Well Format for High-Throughput Real-Time Reverse Transcription Polymerase Chain Reaction for Avian Influenza Testing

Journal of Veterinary Diagnostic Investigation ◽

10.1177/104063870902100513 ◽

2009 ◽

Vol 21 (5) ◽

pp. 679-683 ◽

Cited By ~ 4

Author(s):

Pamela J. Ferro ◽

Jason Osterstock ◽

Bo Norby ◽

Geoffrey T. Fosgate ◽

Blanca Lupiani

Keyword(s):

Polymerase Chain Reaction ◽

Avian Influenza ◽

Real Time ◽

High Throughput ◽

Reverse Transcription ◽

Virus Isolation ◽

Rt Pcr ◽

Chain Reaction ◽

Response Planning ◽

Polymerase Chain

As concerns over the global spread of highly pathogenic avian influenza H5N1 have heightened, more countries are faced with increased surveillance efforts and incident response planning for handling a potential outbreak. The incorporation of molecular techniques in most diagnostic laboratories has enabled fast and efficient testing of many agents of concern, including avian influenza. However, the need for high-throughput testing remains. In this study, the use of a 384–well format for high-throughput real-time reverse transcription polymerase chain reaction (real-time RT-PCR) testing for avian influenza is described. The analytical sensitivity of a real-time RT-PCR assay for avian influenza virus matrix gene with the use of both 96– and 384–well assay formats and serial dilutions of transcribed control RNA were comparable, resulting in similar limits of detection. Of 28 hunter-collected cloacal swabs that were positive by virus isolation, 26 (92.9%) and 27 (96.4%) were positive in the 96– and 384–well assays, respectively; of the 340 hunter-collected swabs that were negative by virus isolation, 45 (13.2%) and 23 (6.8%) were positive in the 96– and 384–well assays, respectively. The data presented herein supports the utility of the 384–well format in the event of an avian influenza outbreak for high-throughput real-time RT-PCR testing.

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