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An infectious particle, similar to but smaller than a virus, that consists solely of a strand of RNA and is capable of causing disease in plants.


(Biochemistry) any of various infective RNA particles, smaller than a virus and known to cause some plant diseases
[C20: from vir(us) + -oid]


(ˈvaɪ rɔɪd)

an infectious agent of plants similar to a virus but consisting of only a short, single strand of RNA without a protein coat.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.viroid - the smallest of viruses; a plant virus with its RNA arranged in a circular chromosome without a protein coat
plant virus - a plant pathogen that is a virus consisting of a single strand of RNA
References in periodicals archive ?
Development of a real-time RT-PCR assay for the detection of Potato spindle tuber viroid.
Standardized RT-PCR conditions for detection and identification of eleven viruses of potato and Potato spindle tuber viroid.
1997, Viroid Life: Perspectives on Nietzsche and the Transhu man Condition, Routledge, Londres.
Development of the molecular methods for potato virus and viroid detection and prevention.
Grasmick ME and SA Slack Detection of potato spindle tuber viroid in true potato seed by bioassay on Rutgers tomato.
section] 7702(14) (2006) (defining plant pests as "any living stage of any of the following that can directly or indirectly injure, cause damage to, or cause disease in any plant or plant product: (A) A protozoan (B) A nonhuman animal (C) A parasitic plant (D) A bacterium (E) A fungus (F) A virus or viroid (G) An infectious agent or other pathogen (H) Airy article similar to or allied with any of the articles specified in the preceding subparagraphs"); id.
A novel usage of random primers for multiplex RT-PCR detection of virus and viroid in aphids, leaves and tubers.
Botanists and agricultural scientists examine virus, viroid, and phytoplasma diseases of both the apple family and the peach family of fruits, because many of the diseases affect both groups.
3-5) There was an increase in free RNA indicating self replicating RNA viroids and free DNA indicating generation of viroid complementary DNA strands by archaeal reverse transcriptase activity.
Keith Ansell Pearson, Viroid Life: Perspectives on Nietzsche and the Transhuman Condition, Routledge, London, 1997, n3, p13.