Experimental Infection of Different Tomato Genotypes with Tomato mosaic virus Led to a Low Viral Population Heterogeneity in the Capsid Protein Encoding Region

Abstract

The complete genome sequence of a Slovak SL-1 isolate of Tomato mosaic virus (ToMV) was determined from the next generation sequencing (NGS) data, further confirming a limited sequence divergence in this tobamovirus species. Tomato genotypes Monalbo, Mobaci and Moperou, respectively carrying the susceptible tm-2 allele or the Tm-1 and Tm-2 resistant alleles, were tested for their susceptibility to ToMV SL-1. Although the three tomato genotypes accumulated ToMV SL-1 to similar amounts as judged by semi-quantitative DAS-ELISA, they showed variations in the rate of infection and symptomatology. Possible differences in the intra-isolate variability and polymorphism between viral populations propagating in these tomato genotypes were evaluated by analysis of the capsid protein (CP) encoding region. Irrespective of genotype infected, the intra-isolate haplotype structure showed the presence of the same highly dominant CP sequence and the low level of population diversity (0.08–0.19%). Our results suggest that ToMV CP encoding sequence is relatively stable in the viral population during its replication in vivo and provides further demonstration that RNA viruses may show high sequence stability, probably as a result of purifying selection.

Evaluation of New Polyclonal Antibody Developed for Serological Diagnostics of Tomato Mosaic Virus

“…After reverse transcription, the cDNA was amplified using primers specific for ToMV SL-1 coat-protein-coding sequences (CP1 and CP2) and primer pairs P1-P6. The obtained amplicons had the expected size and the Sanger sequencing analysis revealed 100% sequence homology with the previously sequenced ToMV SL-1 isolate [29] in both plants.…”

“…The virus originated from a tomato plant manifesting symptoms of virus infection at a local tomato grower in Western Slovakia. Leaves from this plant were collected and stored at −80 • C. The nucleotide sequence of the complete genome of the ToMV SL-1 isolate was determined previously by high-throughput sequencing [29] and included in the GenBank nucleotide database (KY912162, available at: https://www.ncbi.nlm.nih.gov/nucleotide/, accessed on 27 May 2022). This analysis showed that the source tomato plant was infected solely by ToMV without co-infection with other viruses.…”

“…Specific ToMV epitopes were designed by evaluating the antigenic potential of the amino acid sequences of coat proteins from ToMV SL-1 and fifteen other ToMV isolates retrieved from the UniProt knowledgebase [31] (The UniProt Consortium, 2021, available online: https://www.uniprot.org/uniprot/, accessed on 27 May 2022). Homology in the coat protein sequences within them was in the range of 98.6-99.1% [29]. The nucleotide and amino acid sequences were analyzed using CLC Sequence Viewer 8.0.0 (Qiagen, Aarhus, Denmark) and CLC Main Workbench 8.1 software (Qiagen, Aarhus, Denmark), respectively.…”

“…RNA isolated from leaf samples of infected tomato plants 762/15 and 730/15 was used for the confirmation of the identity of ToMV SL-1. ToMV SL-1, used for the inoculation of these plants, was compared with the original nucleotide sequence of ToMV SL-1 isolate [29]. After reverse transcription, the cDNA was amplified using primers specific for ToMV SL-1 coat-protein-coding sequences (CP1 and CP2) and primer pairs P1-P6.…”

Solid Phase Microextraction–Multicapillary Column–Ion Mobility Spectrometry (SPME–MCC–IMS) for Detection of Methyl Salicylate in Tomato Leaves

“…A similar method as reported in ref was used to treat the tomato leaves with tomato ringspot virus (ToRSV) and prepare the leaf samples. The ToRSV inoculation buffer was obtained from Institute of Virology, Biomedical Research Center of Slovak Academy of Sciences (store at −20 °C) . The lower leaves of the tomato plants with an age of 5 weeks were inoculated by ToRSV.…”