Summary of experiments with helicase domain mutant viruses.

a<p>Systemically infected plants/total number of plants tested.</p>b<p>Abbreviations of infection phenotypes = N, none; LD, leaf distortion; M, mosaic; SG, stunted growth; MLD, mild leaf distortion; MM, mild mosaic.</p>c<p>The inoculated cotyledons and the upper leaves of inoculated plants were sampled at 21 dpi. Mean values from triplicates samples are given.</p>d<p>Average of absorbance value and standard errors.</p>e<p>Mean of values in triplicate.