Figure 2

Transient expression of At-Rop1 negatively regulated potato resistance to P. infestans . Agrobacterium tumefaciens (LB4404) carrying CA-AtRop1 and DN-AtRop1constructs were infiltrated into potato leaves at a concentration of OD₆₀₀ = 0.5. A. Development of lesion size on potato leaves after inoculation with P. infestans (5 × 10⁵ zoospore/mL). The left part of the leaf was used as a control by inoculating with water; the right part was inoculated with P. infestans. B. After transient expression of CA-AtRop1 and DN-AtRop1, the lesion area (length by width) was measured at different time point after inoculation with P. infestans. Each value represents the average of three lesions (cm² ± standard deviation). Levels not labeled with the same letter are significantly different at the P < 0.05 level based on the ANOVA. C. The development of P. infestans mycelium at sites where CA-AtRop1 and DN-AtRop1 were transiently expressed was quantified by trypan blue staining. D. The development of P. infestans at transient expression sites 72hpi was quantified by real-time PCR by comparing levels of the specific repetitive DNA sequence of P. infestans (as measure for fungal biomass) relative to potato EF-1α gene (for equilibration). Levels not labeled with the same letter are significantly different at the P < 0.05 level based on the ANOVA. Bars represent averages with standard deviation of three technical replicates.