Chloroplasts Direct antigen coated - enzyme linked immuno sorbent assay Double antibody sandwich - enzyme linked immuno sorbent assay Electron Microscopy Identification Procedures of plant viruses Immuno electron Microscopy Immuno sorbent electron Microscopy Longevity in vitro Micropropagation Microtuberization Minitubers Mitochondrion Monoclonal antibodies Murashige and Skoog Negative Staining Peroxisomes Plantlets Polyclonal antibodies Potato virus Y Production of polyclonal antiserum programmed cell death Purification Scanning electron microscopy Solanum tuberosum L. The dilution end point Thermal inactivation point Tissue culture techniques Tobacco ring spot virus Tobacco veinal necrosis strain of potato virus Y Ultrastructural changes Viral Diseases Virus free potato