• T. O. Diener
  • A. Hadidi


Viroids have been recognized recently as the smallest agents of infectious disease. Viroids differ from viruses by the absence of a dormant phase (virions) and by genomes that are much smaller than those of known viruses (Diener, 1971b). The term “viroid” has been introduced to describe infectious nucleic acids which have properties similar to those of the causal agent of potato spindle tuber disease (Diener, 1971b). Presently known viroids consist solely of a low molecular weight RNA of about 75,000–130,000. Introduction of this RNA into susceptible hosts leads to autonomous replication of the RNA, and, in some hosts, to disease.


Potato Spindle Tuber Viroid Pancreatic Ribonuclease Infected Tomato Plant Molecular Weight Estimate Potato Spindle Tuber Virus 
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Copyright information

© Plenum Press, New York 1977

Authors and Affiliations

  • T. O. Diener
    • 1
  • A. Hadidi
    • 1
  1. 1.Plant Virology Laboratory, Plant Protection Institute, Agricultural Research ServiceU.S. Department of AgricultureBeltsvilleUSA

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