Figure 6.

VIGS of Nb-MAPKKKε Enhances Pathogen Growth.

Silencing of MAPKKKε in N. benthamiana, with either TRV:5′-MAPKKKε or TRV:3′-NbMAPKKKε, followed by inoculation with zoospores of the red fluorescent P. infestans 88069^td enhances the growth of the pathogen compared with control silencing with TRV:GFP.

(A) Fluorescence microscopy images taken at 4 d after zoospore inoculation indicate more hyphal growth on the MAPKKKε-silenced plants.

(B) and (C) Silencing MAPKKKε also enhances the levels of necrosis and sporulation at 5 d after zoospore inoculation.

(D) Lesion area achieved at 5 and 6 d after zoospore inoculation following infection of TRV-treated plants with P. infestans 88069^td. Results are the mean ± se of 40 inoculations from two independent experiments. Asterisks indicate values significantly different from the TRV:GFP control at the same time point (P < 0.05) as determined by one-way ANOVA; all other values were not significantly different (P > 0.05).