Table I.

The effect of SA treatment on the mean number of infection sites in tobacco tissue directly inoculated with either TMV or CMV engineered to express free GFP

ControlSA
Mean no. of infection sites/leaf disc ±sd
TMV.GFP
 Experiment 1 (n = 5 leaf discs  per treatment)12 ± 5.38.4 ± 4
 Experiment 2 (n = 10 leaf  discs per treatment)8.8 ± 4.97.5 ± 4.9
CMV.GFP (n = 3 leaves per treatment)31 ± 4.621 ± 14

Discs and leaves were floated on or sprayed with 1 mmSA for 5 d prior to inoculation.