Morphology and infection symptoms of transgenic Nbsat-12 and RDR6isat-12 plants carrying 35S–asatsiR-12. (A) Morphology of transgenic Nbsat-12 and RDR6isat-12 T0 plants and detection of asatsiR-12 expression levels in these transgenic plants. The corresponding vector transgenic plants (Nbv and RDR6iv plants) were used as controls. A 32P-labeled oligodeoxynucleotide probe specific for asatsiR-12 was used. (B) Infection symptoms of Nbsat-12 and RDR6isat-12 plants and corresponding control (Nbv and RDR6iv) plants inoculated with an SD-CMV infectious clone: CMVwt, containing SD-CMV RNA1, RNA2, and RNA3, or CMVΔ2b, containing CMV RNA1, RNA2Δ2b, and RNA3, in which 2b protein expression is abolished (23). Photographs were taken at 4 and 14 dpi, respectively. Leaves of RDR6isat-12 plants with wild-type CMV-related yellowing turned brown (brown arrow) and dried rapidly compared to leaves of the wild-type CMV-infected Nbsat-12 plants (yellow arrow) at 14 dpi.