Author
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Hammond, Rosemarie |
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Owens, Robert |
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Submitted to: APS Net Plant Pathology Online
Publication Type: Review Article Publication Acceptance Date: 10/13/2006 Publication Date: 10/17/2006 Citation: Hammond, R., Owens, R.A. 2006. Viroids: New and continuing risks for horticultural and agricultural crops. APS Net Feature Article: Available http://www.apsnet.org/online/feature/viroids/. Interpretive Summary: Available on-line. Technical Abstract: One of the most intriguing classes of plant pathogens are the viroids. Subviral pathogens that have been isolated from higher plants afflicted with specific diseases, their hosts include both herbaceous and woody species - agronomic as well as ornamental. Identification of viroid-infected plants can be accomplished by either symptomatology on indicator hosts, a classical method still used in many certification programs, or by molecular methods such as nucleic acid hybridization or polymerase chain reaction. Recent outbreaks of diseases caused by viroids suggest that either current control measures are inadequate or that growers may be unaware of the risks of viroid infection to their crops. In addition, viroids are also being detected in crop species where they were not previously known to occur. In some cases, these infections are latent, but in others, severe disease symptoms develop. These observations raise several intriguing questions: Why are viroid diseases recurring in certain crops where they were previously assumed to be under control? Are viroid infections more common than we know; if so, do they pose a serious threat to modern agriculture? Our review of the literature attempts to address these questions. |
