ARTIFICIAL DEFECTIVE INTERFERING RNAS DERIVED FROM RNA-2 OF BEET NECROTIC YELLOW VEIN VIRUS

Long internal deletions were introduced into cloned cDNA of beet necro tic yellow vein virus RNAs 1-4 and transcripts containing the deletion s were tested for their ability to inhibit replication of viral RNA in Chenopodium quinoa protoplasts and plants. No inhibition was observed with the deletion mutants based on RNAs 1, 3 and 4 but the RNA 2 dele tion mutants all provoked a dramatic inhibition of synthesis of viral RNAs 1 and 2.