ABSTRACT
The term “genetically engineered cross-protection” has been frequently used because, in many cases, the phenotype of resistance mimics that of cross-protection. However, cross-protection is a complex response caused by replication and gene expression from the entire viral genome, only one aspect of which is similar to the resistance conferred by the expression of a virus coat protein gene. R. S. Nelson et al. demonstrated that tomato plants expressing the Tobacco Mosaic Virus (TMV) Coat Protein (CP) gene retain their resistance to TMV infection under field conditions, although the level of CP was decreased slightly under these conditions compared to greenhouse conditions. “Coat protein-mediated resistance,” has been described for plant viruses in several different virus groups. Since 1986, there have been a number of reports of coat protein-mediated resistance in plants of the Solanaceae and Leguminosae. A single report has described CP-mediated resistance against cucumber mosaic virus, the type of the cucumovirus group.
