TABLE OF CONTENTS 



Page 



ACKNOWLEDGEMENTS iii 



ABSTRACT vi 



CHAPTERS 



1 INTRODUCTION 1 



2 USE OF LIGHT MICROSCOPY TO DETECT AND 



DIAGNOSE ORCHID VIRUSES 5 



Introduction 5 



Materials and Methods 6 



Results 10 



Odontoglossum Ringspot Virus 10 



Cymbidium Mosaic Virus 15 



Cucumber Mosaic Virus 18 



Bean Yellow Mosaic Virus 22 



Uncharacterized Bacilliform Virus 25 



Discussion 29 



3 CONFIRMATORY STUDIES OF LIGHT MICROSCOPE 

 OBSERVATIONS 3 3 



Introduction 33 



Materials and Methods 3 4 



Leaf Dips 34 



Thin Sectioning 35 



Immunofluorescence Microscopy 36 



Protein A-Gold Labelling 37 



Results 38 



VaMo Negative Staining 38 



Thin Sectioning 39 



Immunofluorescence Microscopy 43 



Protein A-Gold Labelling 50 



Discussion 56 



4 CONCLUSIONS 6 2 



IV 



