Abstract

                                RNAs play a significant role in regulating gene expression and their principalareas have been exploited for the control of plant viruses by the discoveryof RNA silencing mechanism. RNA silencing or RNA interference (RNAi)is an innovative mechanism that regulates and restricts the amount oftranscripts either by suppressing transcription (TGS) or by the degradationof sequence-specific RNA. RNAi can be used effectively to study the role ofgenes in a variety of eukaryotic organisms by reverse genetics. The technologyhas been employed in several fields such as drug resistance, therapeutics,development of genetically modified animals for research and transgenicplants targeting plant viruses. In plants, small interfering RNAs (siRNA) arethe characteristic of 21 to 22 bp long dsRNA, which has been recognizedby the regulatory mechanism of RNAi and leads to the sequence-specificdegradation of target mRNA. In addition to virus disease control, RNAi canalso be used to control mycotoxins and plant diseases caused by otherorganisms. This review enhances our current knowledge of RNAi and its largerapplications in agriculture, specifically in plant virus disease management.

Key words : RNAi; gene sources;Post-transcriptional gene silencing (PTGS);Silencing suppressors;VIGS