-43- 



sections (Figs. 33, 35, and 38). Sections of these same 

 tissue areas can be obtained for electron microscopy by 

 taking an ultrathin section from the same block from which 

 the toluidine blue section is obtained. The same 

 inclusions can thus be located (Fig. 36 and 39) in these 

 ultrathin sections by their intracellular location in 

 relation to cell organelles noted by light microscopy. 

 Using this method, ORSV, CyMV and CMV inclusions composed 

 of virus particle aggregations (Figs. 34 and 36) were 

 located, as were BYMV inclusions, which were comprised of 

 cylindrical inclusions. Nuclear inclusions containing 

 rhabdovirus particles and granular electron dense materials 

 (Fig. 39) were also located by this method. 

 Immunofluorescence Microscopy 



As described in the chapter 2, CyMV inclusions were 

 preserved by glutaraldehyde fixation. In this 

 investigation, it appeared that glutaraldehyde fixation 

 did not change the properties of CyMV inclusion 

 antigenicity since they still reacted with virus specific 

 antiserum (Figs. 40 and 41). In the newly emerged CMV- 

 infected leaves or flowers of Phalaenopsis , CMV crystal 

 inclusions were easily observed, although the size of 

 crystals varied (Fig. 42). In ORSV-inf ected Cattleya 

 tissues, the paracrystal and stacked-plate inclusions 

 fluoresced (Figs. 43, 44, 45 and 46). These virus- 

 infected tissues did not fluoresce when they were 



