ABSTRACT
The use of virus genes as tools to generate virus resistance in plants (termedpathogen-derived resistance, or PDR) has proven to be a powerful approach for developing crops protected against viruses, and for studying aspects of virus infection in plants. Virus coat protein (CP) gene-mediated protection has been documented for a large number of plant virus families. Potyviruses are among the most numerous of the different families of plant viruses. Potyviruses cause disease in most crop plants, and they can amplify the severity of disease symptoms caused by other viruses due to synergism in mixed infections. This chapter considers what potyvirus genes have been used to generate virus-resistant transgenic plants; what is known (and not known) about the mechanisms of PDR against potyviruses; and what are the prospects for further developments in the area of PDR against potyviruses.
