The Role of Mixed Infections in the Transmission of Plant Viruses by Aphids

INTRODUCTION I suspect that many plant diseases are influenced by associated organisms to a much more profound degree than we have yet realized, not only as to inhibition, but as to acceleration, of the processes. It may be that a number of diseases may require an association of organisms for their occurrence and cannot be produced by infection of one organism alone. These considerations appear to indicate an inviting field for much more extended research. (22)