Coat protein-mediated resistance to Turnip mosaic virus in oilseed rape (Brassica napus)

Oilseed rape (Brassica napus) lines transformed with the coat protein (CP) gene of Turnip mosaic virus (TuMV) were used to determine the effectiveness of resistance to TuMV mediated by CP RNA or coat protein. Lines with one, two, or more copies of transgenes were produced. T-2 and T-3 lines containing the CP gene with a functional start codon synthesised coat protein and showed high, but variable levels of resistance to TuMV (21-96% resistant plants per line). The T-1 and T-2 progeny of all lines carrying the CP gene with a mutated start codon so that RNA but not protein was expressed, were as susceptible to TuMV as controls. Thus, in these experiments we were able to induce CP-mediated resistance, but not RNA-mediated resistance.