Plant Resistance Responses to Viruses

Plants have developed numerous approaches to resist infection by viruses. On the other hand, in many instances viruses have evolved to overcome these various resistance responses and barriers. The extent to which viruses can overcome some or all of these responses and barriers determines the extent to which they are able to colonize plants of a given genotype or species. Resistance against plant viruses occurs at different levels and by various mechanisms, most of which largely remain uncharacterized. Here, we will consider these various levels of resistance, as well as the types of resistance responses, the isolated genes involved in resistance, the signalling pathways that have been described, and the various resistance factors that have been implicated in resistance to specific viruses.