Molecular strategies for engineering resistance to potato viruses

An increasing number of molecular strategies are available for engineering virus resistance in potatoes (Solanum tuberosum ssp. tuberosum L.) using pa thogen-derived or other virus-inhibiting nucleic acid sequences and protein s. Virus resistance has been developed in transgenic plants expressing viru s coat proteins, movement proteins, replicases, untranslatable sense or ant isense RNAs, proteases, defective interfering RNAs, and satellites. Express ion of ribozymes, a double-stranded RNA-specific ribonuclease, antiviral pr oteins, a plant pathogen resistance gene, and plantibodies has also provide d virus resistance. Transgenic plants resistant to several viruses have alr eady been approved by regulatory agencies for commercial release and virus- resistant potato varieties promise to improve yield and quality. Plant prot ection ranges from being specific against closely related strains of the vi rus to broad-spectrum resistance that extends to other virus groups. Progre ss has also been made in combining several strategies to increase the level and number of viruses to which the plant is resistant. Advances in the und erstanding of virus biology and host-pathogen interactions will continue to produce new and improved disease control strategies.