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addition to providing confirmatory data regarding the 

 viral nature of inclusions, this procedure is potentially 

 valuable for the in situ examination of viruses occurring 

 in low titers, and distinguishing viral from non-viral 

 intracellular structures. As shown in this study, the 

 procedure proved useful for capsid and nonstructural 

 proteins . 



LR White resin was suitable for embedding tissues 

 infected with plant viruses. The use of this resin 

 facilitated immunogold labelling studies considerably 

 because it is much less labor intensive than the 

 previously used resins, such as epoxy resin or even 

 Lowicryl resin. 



Another labor-saving improvisation developed in 

 this study was a multi-grid staining apparatus involving 

 simple equipment available in all reasonably equipped 

 scientific laboratories. The device could house at 

 least 10 grids simultaneously for staining and 

 processing for electron microscopy without individual 

 handling of the grids. 



VaMo was an effective negative stain for orchid 

 viruses in leaf dip diagnosis. This stain promoted the 

 congregation of virions to the edge of the droplet on the 

 grid. Therefore, only the droplet edge needed to be 

 scanned in the electron microscope. The stain contrast 

 and resolution of VaMo compared favorably with that of 



