Methods of virus indexing
There is no effective chemical control method against viruses directly. For this reason, the most common method for obtaining virus-free plant is meristem culture technique. Different researchers [6, 7] have also reported that shoot tip remained insufficient for obtaining the virus-free plants. Biological (mechanical inoculation, indexing How are viruses classified? The highest level of virus classification recognises six major groups, based on the nature of the genome: Double-stranded DNA (dsDNA): there are no plant viruses in this group, which is defined to include only those viruses that replicate without an RNA intermediate (see Reverse-transcribing viruses, below). Therefore, it is necessary to ensure that it’s healthy and free from all the known viruses. Virus indexing ensures that mother plant tissue/stock culture (to be used for mass multiplication) are free from any known virus in-turn ensuring the possibility of producing virus free progeny or batch of tissue culture raised plants.