Management of virus disease: host resistance.

There are broadly three major forms of host resistance: non-host resistance where interactions between virus and host always fail; cultivar resistance driven by host resistance genes interacting with virus virulence factors; and induced resistance, the result of chemical or biological triggering of defence responses. This chapter emphasizes the importance of host plant resistance for plant virus disease management. It also describes the differences between virus resistance and disease tolerance. It discusses how can resistance be bred into crop plants, and presents the options for genetically engineered resistance to combat plant virus disease.