Recombination in cucumber mosaic virus in transgenic and non-transgenic plants: in the lab, the greenhouse, and the field.

Virus resistance was one of the very first useful traits introduced into plant genomes, and over the past 18 years, numerous types of highly effective virus resistance transgenes have been created. Nearly all of these resistances are based on expression of a transgene encoding a viral gene,or a part thereof (see Beachy 1997 for review). However, it is interesting to note that only very few virus resistant transgenic plants (VRTPs) are currently cultivated at any significant scale, the notable example of success being the papayas resistant to Papaya ringspot virus widely grown in Hawaii.