PEROXIDASE ISOZYMES IN SOME VIRUS-INFECTED ORCHIDS
In vegetatively propagated plant crops, multiple virus infections are of important consideration in the etiology of virus-infected plants. In a large number of these multiple infections interactions occur (Ross, 1959). Such interactions usually affect the disease syndrome and may alter the course of infection and disease. Although no basic interpretations of the underlying mechanism for these interactions have evolved, changes in symptomatology and in metabolic reactions have been explored. The levels of peroxidase activity have been generally correlated with numerous disease syndromes, and the changes in the peroxidase content of virus-infected tissues have been frequently observed (Farkas and Stahmann, 1966; Loebenstein and Linsey, 1961; Menke and Walker, 1963; Novacky and Hampton, 1968; Suseno and Hampton, 1966; Solymosy et al., 1967).
The association of the Cymbidium mosaic virus, Cym MV, and the Odontoglossum ringspot virus, ORSV, has been frequently observed in the Orchidaceae and its synergistic action in orchids reported (Thornberry and Phillippe, 1967). In Hawaii double infections are frequently associated with severe symptoms, but little or no symptom expressions are manifested in others. This study reports the changes in peroxidase isozyme patterns in some orchids infected with two orchid viruses.