Whereas an average of 2.4 infection foci per leaf were detected on the plants expressing only miR173, plants expressing syn-tasiR-3NCR or syn-tasiR-CP, either with or without miR173, showed high resistance to PPV: a single focus was detected on one of the 23 leaves treated with syn-tasiR-3NCR or syn-tasiR-CP plus miR173 and no focus was detected on any of the 24 leaves expressing syn-tasiR-3NCR or syn-tasiR-CP alone (Fig 5A). The gene discussed is CP; the disease is infection.