1. Next generation sequencing for detection and discovery of plant viruses and viroids : comparison of two approachesAnja Pecman, Denis Kutnjak, Ion Gutiérrez-Aguirre, Ian Adams, Adrian Fox, Neil Boonham, Maja Ravnikar, 2017, original scientific article Abstract: Next generation sequencing (NGS) technologies are becoming routinely employed in different fields of virus research. Different sequencing platforms and sample preparation approaches, in the laboratories worldwide, contributed to a revolution in detection and discovery of plant viruses and viroids. In this work, we are presenting the comparison of two RNA sequence inputs (small RNAs vs. ribosomal RNA depleted total RNA) for the detection of plant viruses by Illumina sequencing. This comparison includes several viruses, which differ in genome organization and viroids from both known families. The results demonstrate the ability for detection and identification of a wide array of known plant viruses/viroids in the tested samples by both approaches. In general, yield of viral sequences was dependent on viral genome organization and the amount of viral reads in the data. A putative novel Cytorhabdovirus, discovered in this study, was only detected by analysing the data generated from ribosomal RNA depleted total RNA and not from the small RNA dataset, due to the low number of short reads in the latter. On the other hand, for the viruses/viroids under study, the results showed higher yields of viral sequences in small RNA pool for viroids and viruses with no RNA replicative intermediates (single stranded DNA viruses).
Keywords: next generation sequencing, small RNA, ribosomal RNA depleted total RNA, detection, plant viruses, plant viroids
Published in DiRROS: 25.07.2024; Views: 100; Downloads: 59
 Full text (1,32 MB)
This document has many files! More... |
2. Systematic comparison of nanopore and illumina sequencing for the detection of plant viruses and viroids using total RNA sequencing approachAnja Pecman, Ian Adams, Ion Gutiérrez-Aguirre, Adrian Fox, Neil Boonham, Maja Ravnikar, Denis Kutnjak, 2022, original scientific article Abstract: High-throughput sequencing (HTS) has become an important tool for plant virus detection and discovery. Nanopore sequencing has been rapidly developing in the recent years and offers new possibilities for fast diagnostic applications of HTS. With this in mind, a study was completed, comparing the most established HTS platform (MiSeq benchtop sequencer—Illumina), with the MinION sequencer (Oxford Nanopore Technologies) for the detection of plant viruses and viroids. Method comparisons were performed on five selected samples, containing two viroids, which were sequenced using nanopore technology for the first time and 11 plant viruses with different genome organizations. For all samples, sequencing libraries for the MiSeq were prepared from ribosomal RNA-depleted total RNA (rRNA-depleted totRNA) and for MinION sequencing, direct RNA sequencing of totRNA was used. Moreover, for one of the samples, which contained five different plant viruses and a viroid, three additional variations of sample preparation for MinION sequencing were also used: direct RNA sequencing of rRNA-depleted totRNA, cDNA-PCR sequencing of totRNA, and cDNA-PCR sequencing of rRNA-depleted totRNA. Whilst direct RNA sequencing of total RNA was the quickest of the tested approaches, it was also the least sensitive: using this approach, we failed to detect only one virus that was present in a sample at an extremely low titer. All other MinION sequencing approaches showed improved performance with outcomes similar to Illumina sequencing, with cDNA-PCR sequencing of rRNA-depleted totRNA showing the best performance amongst tested nanopore MinION sequencing approaches. Moreover, when enough sequencing data were generated, high-quality consensus viral genome sequences could be reconstructed from MinION sequencing data, with high identity to the ones generated from Illumina data. The results of this study implicate that, when an appropriate sample and library preparation are selected, nanopore MinION sequencing could be used for the detection of plant viruses and viroids with similar performance as Illumina sequencing. Taken as a balance of practicality and performance, this suggests that MinION sequencing may be an ideal tool for fast and affordable virus diagnostics.
Keywords: high-throughput sequencing, plant virus, viroid detection, comparison, nanopore MinION sequencing, illumina MiSeq sequencing
Published in DiRROS: 16.07.2024; Views: 132; Downloads: 112
Full text (2,84 MB)
This document has many files! More... |
3. Tomato brown rugose fruit virus in aqueous environments : survival and significance of water-mediated transmissionNataša Mehle, Katarina Bačnik, Irena Bajde, Jakob Brodarič, Adrian Fox, Ion Gutiérrez-Aguirre, Miha Kitek, Denis Kutnjak, Yue Lin Loh, Olivera Maksimović, Maja Ravnikar, Elise Vogel, Christine Vos, Ana Vučurović, 2023, original scientific article Abstract: Tomato brown rugose fruit virus (ToBRFV) has recently emerged as a major disease of tomatoes and peppers. ToBRFV is a seed- and contact-transmitted virus. In Slovenia, ToBRFV RNA was detected in samples of wastewater, river, and water used to irrigate plants. Even though the source of detected RNA could not be clearly established, this raised the question of the significance of the detection of ToBRFV in water samples and experimental studies were performed to address this question. The data presented here confirm that the release of virus particles from the roots of infected plants is a source of infectious ToBRFV particles in water and that the virus can remain infective up to four weeks in water stored at room temperature, while its RNA can be detected for much longer. These data also indicate that irrigation with ToBRFV-contaminated water can lead to plant infection. In addition, it has been shown that ToBRFV circulated in drain water in commercial tomato greenhouses from other European countries and that an outbreak of ToBRFV can be detected by regular monitoring of drain water. A simple method for concentrating ToBRFV from water samples and a comparison of the sensitivity of different methods, including the determination of the highest ToBRFV dilution still capable of infecting test plants, were also investigated. The results of our studies fill the knowledge gaps in the epidemiology and diagnosis of ToBRFV, by studying the role of water-mediated transmission, and provide a reliable risk assessment to identify critical points for monitoring and control.
Keywords: tomato brown rugose fruit virus, tomato, hydroponics, water-linked epidemiology, survival
Published in DiRROS: 12.07.2024; Views: 119; Downloads: 130
Full text (3,00 MB)
This document has many files! More... |
