Studies on the Resistance Mediated by Three Mutants of TMV 54K Protein Gene

Three deletion mutants of tobacco mosaic virus (TMV) 54-kD putative replicase gene (54K) were obtained by PCR, and cloned into plant expression vector p208, then transformed into Nicotiana tabacum L. cv. SR1 by Agrobacterium tumefaciens (Smith et Townsend) Conn Ti plasmid-mediated transformation. All the transgenic plants with the N-terminal deletion mutant, the C-terminal deletion mutant and the only 261 nucleotides region from the central part of the 54K ORF showed significant resistance against TMV. 