Nanopore-Based Complete Genome Sequence of a Sri Lankan Cassava Mosaic Virus (Geminivirus) Strain from Thailand

NanoViromics: long-read sequencing of dsRNA for plant virus and viroid rapid detection

There is a global need for identifying viral pathogens, as well as for providing certified clean plant materials, in order to limit the spread of viral diseases. A key component of management programs for viral-like diseases is having a diagnostic tool that is quick, reliable, inexpensive, and easy to use. We have developed and validated a dsRNA-based nanopore sequencing protocol as a reliable method for detecting viruses and viroids in grapevines. We compared our method, which we term direct-cDNA sequencing from dsRNA (dsRNAcD), to direct RNA sequencing from rRNA-depleted total RNA (rdTotalRNA), and found that it provided more viral reads from infected samples. Indeed, dsRNAcD was able to detect all of the viruses and viroids detected using Illumina MiSeq sequencing (dsRNA-MiSeq). Furthermore, dsRNAcD sequencing was also able to detect low-abundance viruses that rdTotalRNA sequencing failed to detect. Additionally, rdTotalRNA sequencing resulted in a false-positive viroid identification due to the misannotation of a host-driven read. Two taxonomic classification workflows, DIAMOND & MEGAN (DIA & MEG) and Centrifuge & Recentrifuge (Cent & Rec), were also evaluated for quick and accurate read classification. Although the results from both workflows were similar, we identified pros and cons for both workflows. Our study shows that dsRNAcD sequencing and the proposed data analysis workflows are suitable for consistent detection of viruses and viroids, particularly in grapevines where mixed viral infections are common.

Translating virome analyses to support biosecurity, on-farm management, and crop breeding

Virome analysis via high-throughput sequencing (HTS) allows rapid and massive virus identification and diagnoses, expanding our focus from individual samples to the ecological distribution of viruses in agroecological landscapes. Decreases in sequencing costs combined with technological advances, such as automation and robotics, allow for efficient processing and analysis of numerous samples in plant disease clinics, tissue culture laboratories, and breeding programs. There are many opportunities for translating virome analysis to support plant health. For example, virome analysis can be employed in the development of biosecurity strategies and policies, including the implementation of virome risk assessments to support regulation and reduce the movement of infected plant material. A challenge is to identify which new viruses discovered through HTS require regulation and which can be allowed to move in germplasm and trade. On-farm management strategies can incorporate information from high-throughput surveillance, monitoring for new and known viruses across scales, to rapidly identify important agricultural viruses and understand their abundance and spread. Virome indexing programs can be used to generate clean germplasm and seed, crucial for the maintenance of seed system production and health, particularly in vegetatively propagated crops such as roots, tubers, and bananas. Virome analysis in breeding programs can provide insight into virus expression levels by generating relative abundance data, aiding in breeding cultivars resistant, or at least tolerant, to viruses. The integration of network analysis and machine learning techniques can facilitate designing and implementing management strategies, using novel forms of information to provide a scalable, replicable, and practical approach to developing management strategies for viromes. In the long run, these management strategies will be designed by generating sequence databases and building on the foundation of pre-existing knowledge about virus taxonomy, distribution, and host range. In conclusion, virome analysis will support the early adoption and implementation of integrated control strategies, impacting global markets, reducing the risk of introducing novel viruses, and limiting virus spread. The effective translation of virome analysis depends on capacity building to make benefits available globally.

Analysis of proteomic changes in cassava cv. Kasetsart 50 caused by Sri Lankan cassava mosaic virus infection

BACKGROUND

Sri Lankan cassava mosaic virus (SLCMV) is a plant virus causing significant economic losses throughout Southeast Asia. While proteomics has the potential to identify molecular markers that could assist the breeding of virus resistant cultivars, the effects of SLCMV infection in cassava have not been previously explored in detail.

RESULTS

Liquid Chromatography-Tandem Mass Spectrometry (LC/MS-MS) was used to identify differentially expressed proteins in SLCMV infected leaves, and qPCR was used to confirm changes at mRNA levels. LC/MS-MS identified 1,813 proteins, including 479 and 408 proteins that were upregulated in SLCMV-infected and healthy cassava plants respectively, while 109 proteins were detected in both samples. Most of the identified proteins were involved in biosynthetic processes (29.8%), cellular processes (20.9%), and metabolism (18.4%). Transport proteins, stress response molecules, and proteins involved in signal transduction, plant defense responses, photosynthesis, and cellular respiration, although present, only represented a relatively small subset of the detected differences. RT-qPCR confirmed the upregulation of WRKY 77 (A0A140H8T1), WRKY 83 (A0A140H8T7), NAC 6 (A0A0M4G3M4), NAC 35 (A0A0M5JAB4), NAC 22 (A0A0M5J8Q6), NAC 54 (A0A0M4FSG8), NAC 70 (A0A0M4FEU9), MYB (A0A2C9VER9 and A0A2C9VME6), bHLH (A0A2C9UNL9 and A0A2C9WBZ1) transcription factors. Additional upregulated transcripts included receptors, such as receptor-like serine/threonine-protein kinase (RSTK) (A0A2C9UPE4), Toll/interleukin-1 receptor (TIR) (A0A2C9V5Q3), leucine rich repeat N-terminal domain (LRRNT_2) (A0A2C9VHG8), and cupin (A0A199UBY6). These molecules participate in innate immunity, plant defense mechanisms, and responses to biotic stress and to phytohormones.

CONCLUSIONS

We detected 1,813 differentially expressed proteins infected cassava plants, of which 479 were selectively upregulated. These could be classified into three main biological functional groups, with roles in gene regulation, plant defense mechanisms, and stress responses. These results will help identify key proteins affected by SLCMV infection in cassava plants.

How do emerging long-read sequencing technologies function in transforming the plant pathology research landscape?

Long-read sequencing technologies are revolutionizing the sequencing and analysis of plant and pathogen genomes and transcriptomes, as well as contributing to emerging areas of interest in plant-pathogen interactions, disease management techniques, and the introduction of new plant varieties or cultivars. Long-read sequencing (LRS) technologies are progressively being implemented to study plants and pathogens of agricultural importance, which have substantial economic effects. The variability and complexity of the genome and transcriptome affect plant growth, development and pathogen responses. Overcoming the limitations of second-generation sequencing, LRS technology has significantly increased the length of a single contiguous read from a few hundred to millions of base pairs. Because of the longer read lengths, new analysis methods and tools have been developed for plant and pathogen genomics and transcriptomics. LRS technologies enable faster, more efficient, and high-throughput ultralong reads, allowing direct sequencing of genomes that would be impossible or difficult to investigate using short-read sequencing approaches. These benefits include genome assembly in repetitive areas, creating more comprehensive and exact genome determinations, assembling full-length transcripts, and detecting DNA and RNA alterations. Furthermore, these technologies allow for the identification of transcriptome diversity, significant structural variation analysis, and direct epigenetic mark detection in plant and pathogen genomic regions. LRS in plant pathology is found efficient for identifying and characterization of effectors in plants as well as known and unknown plant pathogens. In this review, we investigate how these technologies are transforming the landscape of determination and characterization of plant and pathogen genomes and transcriptomes efficiently and accurately. Moreover, we highlight potential areas of interest offered by LRS technologies for future study into plant-pathogen interactions, disease control strategies, and the development of new plant varieties or cultivars.

Viroscope: Plant viral diagnosis from high-throughput sequencing data using biologically-informed genome assembly coverage

High-throughput sequencing (HTS) methods are transforming our capacity to detect pathogens and perform disease diagnosis. Although sequencing advances have enabled accessible and point-of-care HTS, data analysis pipelines have yet to provide robust tools for precise and certain diagnosis, particularly in cases of low sequencing coverage. Lack of standardized metrics and harmonized detection thresholds confound the problem further, impeding the adoption and implementation of these solutions in real-world applications. In this work, we tackle these issues and propose biologically-informed viral genome assembly coverage as a method to improve diagnostic certainty. We use the identification of viral replicases, an essential function of viral life cycles, to define genome coverage thresholds in which biological functions can be described. We validate the analysis pipeline, Viroscope, using field samples, synthetic and published datasets, and demonstrate that it provides sensitive and specific viral detection. Furthermore, we developed Viroscope.io a web-service to provide on-demand HTS data viral diagnosis to facilitate adoption and implementation by phytosanitary agencies to enable precise viral diagnosis.

Mitochondrial Genetic Diversity of Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) Associated with Cassava in Lao PDR

Cassava Mosaic Disease (CMD) caused by Sri Lankan cassava mosaic virus (SLCMV), has rapidly spread in Southeast Asia (SEA) since 2016. Recently it has been documented in Lao PDR. Previous reports have identified whitefly species of B. tabaci as potential vectors of CMD in SEA, but their occurrence and distribution in cassava fields is not well known. We conducted a countrywide survey in Lao PDR for adult whiteflies in cassava fields, and determined the abundance and genetic diversity of the B. tabaci species complex using mitochondrial cytochrome oxidase I (mtCOI) sequencing. In order to expedite the process, PCR amplifications were performed directly on whitefly adults without DNA extraction, and mtCOI sequences obtained using nanopore portable-sequencing technology. Low whitefly abundances and two cryptic species of the B. tabaci complex, Asia II 1 and Asia II 6, were identified. This is the first work on abundance and genetic identification of whiteflies associated with cassava in Lao PDR. This study indicates currently only a secondary role for Asia II in spreading CMD or as a pest. Routine monitoring and transmission studies on Asia II 6 should be carried out to establish its potential role as a vector of SLCMV in this region.

Nanopore sequencing technology and its application in plant virus diagnostics

Plant viruses threaten crop yield and quality; thus, efficient and accurate pathogen diagnostics are critical for crop disease management and control. Recent advances in sequencing technology have revolutionized plant virus research. Metagenomics sequencing technology, represented by next-generation sequencing (NGS), has greatly enhanced the development of virus diagnostics research because of its high sensitivity, high throughput and non-sequence dependence. However, NGS-based virus identification protocols are limited by their high cost, labor intensiveness, and bulky equipment. In recent years, Oxford Nanopore Technologies and advances in third-generation sequencing technology have enabled direct, real-time sequencing of long DNA or RNA reads. Oxford Nanopore Technologies exhibit versatility in plant virus detection through their portable sequencers and flexible data analyses, thus are wildly used in plant virus surveillance, identification of new viruses, viral genome assembly, and evolution research. In this review, we discuss the applications of nanopore sequencing in plant virus diagnostics, as well as their limitations.

A New Jasmine Virus C Isolate Identified by Nanopore Sequencing Is Associated to Yellow Mosaic Symptoms of Jasminum officinale in Italy

Some plants of Jasminum officinale were selected in a nursery for investigation of sanitary status of candidate mother plants before vegetative propagation. The presence of yellow spots and leaf discoloration symptoms pushed for a generic diagnosis through deep sequencing to discover systemic pathogens. Either dsRNA or total RNA were extracted and used in nanopore and Illumina platform for cDNA-PCR, direct RNA and total RNA rRNA-depleted sequencing. A few single reads obtained by nanopore technology or assembled contigs gave unequivocal annotation for the only presence of a jasmine virus C (JaVC, a putative member of genus Carlavirus) isolate. The full-length genome of this isolate was reconstructed, spanning 8490 nucleotides (nt). This isolate shared 90.9% similarity with coat protein sequences and 84% with the entire ORF1 polyprotein, with the other two available JaVC full genomes, isolated from infections in J. sambac in Taiwan and China. The overall nucleotide identity shared by the newly discovered Italian isolate with the Chinese JaVC full genomes was 76.14% (Taiwan) and 75.60% (Fujian). The application of quick nanopore sequencing for virus discovery was assessed. The identification of the virus in a new ornamental host species, largely used in gardening, creates a concern for the potential virus spread and need of testing for production of clean vegetative material.

Complete genome sequence of a novel secovirid infecting cassava in the Americas

We report the complete genome sequence of a field isolate of a novel bipartite secovirid infecting cassava in Colombia, provisionally named "cassava torrado-like virus" (CsTLV). The genome sequence was obtained using Oxford Nanopore Technology, and the 5’ ends were confirmed by RACE. The RNA1 is 7252 nucleotides (nt) long, encoding a polyprotein of 2336 amino acids (aa) containing the typical “replication block”, conserved torradovirus motifs, and a Maf/Ham1 domain, which is not commonly found in viral genomes. The RNA2 is 4469 nt long and contains two overlapping ORFs encoding proteins of 226 and 1179 aa, showing the characteristic genome arrangement of members of the genus Torradovirus.

Cassava mosaic disease and its management in Southeast Asia

Key message

Status of the current outbreak of cassava mosaic disease (CMD) in Southeast Asia was reviewed. Healthy cassava seed production and dissemination systems have been established in Vietnam and Cambodia, along with integrated disease and pest management systems, to combat the outbreak.

Abstract

Cassava (Manihot esculenta Crantz) is one of the most important edible crops in tropical and subtropical regions. Recently, invasive insect pests and diseases have resulted in serious losses to cassava in Southeast Asia. In this review we discuss the current outbreak of cassava mosaic disease (CMD) caused by the Sri Lankan cassava mosaic virus (SLCMV) in Southeast Asia, and summarize similarities between SLCMV and other cassava mosaic begomoviruses. A SATREPS (Science and Technology Research Partnership for Sustainable Development) project “Development and dissemination of sustainable production systems based on invasive pest management of cassava in Vietnam, Cambodia and Thailand”, was launched in 2016, which has been funded by The Japan International Cooperation Agency (JICA) and The Japan Science and Technology Agency (JST), Japan. The objectives of SATREPS were to establish healthy seed production and dissemination systems for cassava in south Vietnam and Cambodia, and to develop management systems for plant diseases and insect pests of cassava. To achieve these goals, model systems of healthy seed production in Vietnam and Cambodia have been developed incorporating CMD-resistant planting materials through international networks with The International Center for Tropical Agriculture (CIAT) and The International Institute of Tropical Agriculture (IITA).

Supplementary Information

The online version contains supplementary material available at 10.1007/s11103-021-01168-2.

Survey and molecular detection of Sri Lankan cassava mosaic virus in Thailand

Cassava plantations in an area of 458 hectares spanning five provinces along the Thailand–Cambodia border were surveyed from October 2018 to July 2019 to determine the prevalence of cassava mosaic disease (CMD) caused by Sri Lankan cassava mosaic virus (SLCMV) in the region. CMD prevalence was 40% in the whole area and 80% in Prachinburi, 43% in Sakaeo, 37% in Burium, 25% in Surin, and 19% in Sisaket provinces. Disease incidence of CMD was highest 43.08% in Sakaeo, followed by 26.78% in Prachinburi, 7% in Burium, 2.58% in Surin, and 1.25% in Sisaket provinces. Disease severity of CMD symptoms was mild chlorosis to moderate mosaic (2–3). The greatest disease severity was recorded in Prachinburi and Sakaeo provinces. Asymptomatic plants were identified in Surin (12%), Prachinburi (5%), Sakaeo (0.2%), and Buriram (0.1%) by PCR analysis. Cassava cultivars CMR-89 and Huai Bong 80 were susceptible to CMD. In 95% of cases, the infection was transmitted by whiteflies (Bemisia tabaci), which were abundant in Sakaeo, Buriram, and Prachinburi but were sparse in Surin; their densities were highest in May and June 2019. Nucleotide sequencing of the mitochondrial cytochrome oxidase 1 (mtCO1) gene of whiteflies in Thailand revealed that it was similar to the mtCO1 gene of Asia II 1 whitefly. Furthermore, the AV1 gene of SLCMV—which encodes the capsid protein—showed 90% nucleotide identity with SLCMV. Phylogenetic analysis of completed nucleotide sequences of DNA-A and DNA-B components of the SLCMV genome determined by rolling circle amplification (RCA) indicated that they were similar to the nucleotide sequence of SLCMV isolates from Thailand, Vietnam, and Cambodia. These results provide important insights into the distribution, impact, and spread of CMD and SLCMV in Thailand.

An optimized nucleic acid isolation protocol for virus diagnostics in cassava (Manihot esculenta Crantz.)

Our group works on the detection and characterization of cassava viruses, supporting projects that involve large scale pathogen surveillance activities and resistance screening assays in multiple and remote locations. In order to comply with these applications, nucleic acid isolation protocols need to be cost effective, adjusted for samples that will stand long distance transport and harsh storage conditions, while maximizing the yield and quality of the nucleic acid extracts obtained. The method we describe here has been widely used and validated using different downstream tests (including, but not limited to, Rolling Circle Amplification and Illumina and Nanopore sequencing), but is currently unpublished. The protocol begins with milligram amounts of dry leaf samples stored in silica gel, does not require liquid Nitrogen nor phenol extraction and produces an average of 2.11 µg of nucleic acids per mg of dry tissue.•DNA purity estimations reveal OD260/280 ratios above 2.0 and OD260/230 ratios above 1.7, even for samples stored in silica gel for several months.•The high quality of the extracts is suitable for detection of DNA and RNA viruses, with high efficiency.•We suggest this method could be used as part of a gold standard kit for virus detection in cassava.

Nanopore Sequencing Is a Credible Alternative to Recover Complete Genomes of Geminiviruses

Next-generation sequencing (NGS), through the implementation of metagenomic protocols, has led to the discovery of thousands of new viruses in the last decade. Nevertheless, these protocols are still laborious and costly to implement, and the technique has not yet become routine for everyday virus characterization. Within the context of CRESS DNA virus studies, we implemented two alternative long-read NGS protocols, one that is agnostic to the sequence (without a priori knowledge of the viral genome) and the other that use specific primers to target a virus (with a priori). Agnostic and specific long read NGS-based assembled genomes of two capulavirus strains were compared to those obtained using the gold standard technique of Sanger sequencing. Both protocols allowed the detection and accurate full genome characterization of both strains. Globally, the assembled genomes were very similar (99.5-99.7% identity) to the Sanger sequences consensus, but differences in the homopolymeric tracks of these sequences indicated a specific lack of accuracy of the long reads NGS approach that has yet to be improved. Nevertheless, the use of the bench-top sequencer has proven to be a credible alternative in the context of CRESS DNA virus study and could offer a new range of applications not previously accessible.

A Primer on the Analysis of High-Throughput Sequencing Data for Detection of Plant Viruses

High-throughput sequencing (HTS) technologies have become indispensable tools assisting plant virus diagnostics and research thanks to their ability to detect any plant virus in a sample without prior knowledge. As HTS technologies are heavily relying on bioinformatics analysis of the huge amount of generated sequences, it is of utmost importance that researchers can rely on efficient and reliable bioinformatic tools and can understand the principles, advantages, and disadvantages of the tools used. Here, we present a critical overview of the steps involved in HTS as employed for plant virus detection and virome characterization. We start from sample preparation and nucleic acid extraction as appropriate to the chosen HTS strategy, which is followed by basic data analysis requirements, an extensive overview of the in-depth data processing options, and taxonomic classification of viral sequences detected. By presenting the bioinformatic tools and a detailed overview of the consecutive steps that can be used to implement a well-structured HTS data analysis in an easy and accessible way, this paper is targeted at both beginners and expert scientists engaging in HTS plant virome projects.

Current Developments and Challenges in Plant Viral Diagnostics: A Systematic Review

Plant viral diseases are the foremost threat to sustainable agriculture, leading to several billion dollars in losses every year. Many viruses infecting several crops have been described in the literature; however, new infectious viruses are emerging frequently through outbreaks. For the effective treatment and prevention of viral diseases, there is great demand for new techniques that can provide accurate identification on the causative agents. With the advancements in biochemical and molecular biology techniques, several diagnostic methods with improved sensitivity and specificity for the detection of prevalent and/or unknown plant viruses are being continuously developed. Currently, serological and nucleic acid methods are the most widely used for plant viral diagnosis. Nucleic acid-based techniques that amplify target DNA/RNA have been evolved with many variants. However, there is growing interest in developing techniques that can be based in real-time and thus facilitate in-field diagnosis. Next-generation sequencing (NGS)-based innovative methods have shown great potential to detect multiple viruses simultaneously; however, such techniques are in the preliminary stages in plant viral disease diagnostics. This review discusses the recent progress in the use of NGS-based techniques for the detection, diagnosis, and identification of plant viral diseases. New portable devices and technologies that could provide real-time analyses in a relatively short period of time are prime important for in-field diagnostics. Current development and application of such tools and techniques along with their potential limitations in plant virology are likewise discussed in detail.

First report of Sri Lankan cassava mosaic virus and Cassava Mosaic Disease in Laos

Cassava (Manihot esculenta Crantz) has been traditionally grown as a subsistence crop in Laos, but in recent years cassava cultivation in this country has expanded and is becoming a 'cash crop' for farmers (Malik et al., 2020). This also means that cassava vegetative seed (stakes) is rapidly multiplied and distributed. One of the most important diseases affecting cassava in the world is the Cassava Mosaic Disease (CMD), caused by several species of begomoviruses and disseminated by infected stakes or vectored by the whitefly Bemisia tabaci (Legg et al., 2014). Sri Lankan cassava mosaic virus (SLCMV), a bipartite begomovirus, is the virus species causing CMD in Southeast Asia (SEA) and is widespread in Cambodia, Vietnam, Thailand and south China (Siriwan et al., 2020). During field surveys on July 12 to 14, 2020, the team in south Laos, surveyed 8 fields along the border with Cambodia, in the southern provinces of Attapeu and Champassack and identified CMD symptoms (Supplementary Figure 1A) in only one of the fields, located at Kong District of the Champassack province (GPS coordinates 13.94325, 105.99102). From these 8 fields, samples were collected from every third plant in an X pattern. Photographs from each sampled plant were taken and uploaded into CIAT's PestDisPlace platform (https://pestdisplace.org), for CMD symptom confirmation (Supplementary Figure 1B). Leaf samples were sent to the laboratory for PCR using primers SLCMV-F 5'-ATGTCGAAGCGACCAGCAGATATAAT-3' and SLCMV-R 5'-TTAATTGCTGACCGAATCGTAGAAG-3' targeting the AV1 gene (Dutt et al., 2005), following the protocol described in Siriwan et al. (2020) and primers SLCMV-B-F1 5'-ACCGGATGGCCGCGCCCCCCTCT-3' and SLCMV-B-606R 5'-CACCTACCCTGTTATCGCTAAG-3' targeting part of the BV1 gene. Out of 60 samples collected for the field in Kong district, eleven (18.3%) resulted PCR positive to SLCMV (to DNA-A and DNA-B) but only four plants (6.7%) showed symptoms of CMD (see Supplementary Figure 1B and 1C). None of the samples in the other seven fields had CMD symptoms nor was SLCMV detected in any of these plants. Furthermore, the presence of CMD symptoms in the old leaves of the plants in the affected field suggests that the virus was introduced with contaminated stakes. The complete bipartite genome of one isolate (Champ1), was amplified by Rolling Circle Amplification and sequenced with the nanopore MinION technology as described by Leiva et al. (2020). The sequences were submitted to GenBank under accession nos MT946533 (DNA-A) and MT946534 (DNA-B). A phylogenetic tree for SLCMV and a link to the open SLCMV Nextstrain map (Hadfield et al., 2018) is included in Supplementary Figure 2. The sequences of the DNA-A and DNA-B components of the Champ1 isolate were nearly identical to those of anisolate of SLCMV from Ratanakiri, Cambodia (99.72% for DNA-A and 99.82 for DNA-B; Wang et al., 2016). Phylogenetic analysis (Supplementary Figure 2), grouped isolate Champ1 with those that form the cluster of SEA isolates that contain the shorter version of the rep gene (Siriwan et al., 2020). This short version of rep present a deletion of 7 amino acids at the C-terminus, which is involved in host responses to SLCMV (Wang et al., 2020). The confirmation of CMD and SLCMV in the border between Laos and Cambodia should be followed by disease containment and management strategies, particularly given that the majority cassava varieties grown in Laos are from neighbor countries, most of which have already reported the presence of CMD. Acknowledgements We thank all staff from the CIAT's Cassava Program and the Plant Protection Center of Laos in Vientiane. We acknowledge financial support from the Australian Centre for International Agricultural Research (ACIAR) and the CGIAR Research Program on Roots, Tubers and Bananas (RTB) (https://www.cgiar.org/funders/).

Turfgrass Disease Diagnosis: Past, Present, and Future

Turfgrass is a multibillion-dollar industry severely affected by plant pathogens including fungi, bacteria, viruses, and nematodes. Many of the diseases in turfgrass have similar signs and symptoms, making it difficult to diagnose the specific problem pathogen. Incorrect diagnosis leads to the delay of treatment and excessive use of chemicals. To effectively control these diseases, it is important to have rapid and accurate detection systems in the early stages of infection that harbor relatively low pathogen populations. There are many methods for diagnosing pathogens on turfgrass. Traditional methods include symptoms, morphology, and microscopy identification. These have been followed by nucleic acid detection and onsite detection techniques. Many of these methods allow for rapid diagnosis, some even within the field without much expertise. There are several methods that have great potential, such as high-throughput sequencing and remote sensing. Utilization of these techniques for disease diagnosis allows for faster and accurate disease diagnosis and a reduction in damage and cost of control. Understanding of each of these techniques can allow researchers to select which method is best suited for their pathogen of interest. The objective of this article is to provide an overview of the turfgrass diagnostics efforts used and highlight prospects for disease detection.

Complete Genome Sequence of the Plant Pathogen Ralstonia solanacearum Strain CIAT-078, Isolated in Colombia, Obtained Using Oxford Nanopore Technology

Moko is one of the main diseases affecting banana and plantain in Colombia. Here, we report the genome sequence of the causal agent, the bacterium Ralstonia solanacearum (Smith) strain CIAT-078, collected in 2004 from affected plantains in central-west Colombia. The assembled genome was obtained using Oxford Nanopore Technology.

Moko is one of the main diseases affecting banana and plantain in Colombia. Here, we report the genome sequence of the causal agent, the bacterium Ralstonia solanacearum (Smith) strain CIAT-078, collected in 2004 from affected plantains in central-west Colombia. The assembled genome was obtained using Oxford Nanopore Technology.