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A virus has either a DNA or an RNA genome and is called a DNA virus or an RNA virus, respectively. The vast majority of viruses have RNA genomes. Plant viruses tend to have single-stranded RNA genomes and bacteriophages tend to have double-stranded DNA genomes.
Quora User, Indecipherable Indecisive Intuitive Incorrigible. Yes, viruses and bacteria affect plants causing a variety of plant diseases. Viruses infecting plants are predominantly RNA viruses. The viruses enter the plant through lesions caused by insects, grafting or even growth.