Plant diseases are threat to world agriculture. Significant yield losses occur due to attack of pathogens in most of the agricultural and horticultural crop species. More than 70 per cent of all the major crop diseases are caused by fungi. It has been estimated that out of 36.5 per cent average total losses, 14.1 per cent by diseases 10.2 per cent by insects, 12.2 per cent by weeds. Plant diseases are usually handled with applications of chemicals. For some diseases, chemical control is very effective; but it is often non-specific in its effects, killing beneficial organisms and may have undesirable effects on health, safety and cause environmental risks. Traditional plant breeding methods have been used to develop cultivars resistant to various diseases. However this process is time consuming and limited availability of genetic resources. So in order to sustain high quality yielding and disease resistant plants, there is need to incorporate some biotechnological practices like gene silencing technologies to the breeding programmes. Gene silencing refers to general processes of interruption or suppression of transcription or translation of the mRNA of the target gene by mechanisms other than genetic modification. It is cost effective, ecofriendly and useful approach in future gene therapy.